Sample records for diamond drill bit

  1. Advanced "Dagang" Screw Drill and Man-made Diamond Bit

    Wu Zhenya


    @@ Central Machinery Plant, a state enterprise, is a comprehensive petroleum machinery enterprise mainly manufacturing petroleum machinery equipment and drilling & production fillings, also maintaining oilfield construction equipment and submersible electrical pumps. In 1992,the plant was appointed to manufacture positive displacement drill, reciprocating pump, man-made diamond bit, downhole tool and roller precision chain, and to maintain submersible electrical pumps by CNPC.

  2. Protected Polycrystalline Diamond Compact Bits For Hard Rock Drilling

    Robert Lee Cardenas


    Two bits were designed. One bit was fabricated and tested at Terra-Tek's Drilling Research Laboratory. Fabrication of the second bit was not completed due to complications in fabrication and meeting scheduled test dates at the test facility. A conical bit was tested in a Carthage Marble (compressive strength 14,500 psi) and Sierra White Granite (compressive strength 28,200 psi). During the testing, Hydraulic Horsepower, Bit Weight, Rotation Rate, were varied for the Conical Bit, a Varel Tricone Bit and Varel PDC bit. The Conical Bi did cut rock at a reasonable rate in both rocks. Beneficial effects from the near and through cutter water nozzles were not evident in the marble due to test conditions and were not conclusive in the granite due to test conditions. At atmospheric drilling, the Conical Bit's penetration rate was as good as the standard PDC bit and better than the Tricone Bit. Torque requirements for the Conical Bit were higher than that required for the Standard Bits. Spudding the conical bit into the rock required some care to avoid overloading the nose cutters. The nose design should be evaluated to improve the bit's spudding characteristics.

  3. Development of a jet-assisted polycrystalline diamond drill bit

    Pixton, D.S.; Hall, D.R.; Summers, D.A.; Gertsch, R.E.


    A preliminary investigation has been conducted to evaluate the technical feasibility and potential economic benefits of a new type of drill bit. This bit transmits both rotary and percussive drilling forces to the rock face, and augments this cutting action with high-pressure mud jets. Both the percussive drilling forces and the mud jets are generated down-hole by a mud-actuated hammer. Initial laboratory studies show that rate of penetration increases on the order of a factor of two over unaugmented rotary and/or percussive drilling rates are possible with jet-assistance.

  4. The new designs of diamond drill bits for composite polymers tooling

    Ruslan Yu. Melentiev


    Full Text Available The author explores the drilling operation of some new engineering materials such as carbon fiber reinforced plastics (CFRP and other polymers that have an anisotropic structure, high-strength and elastic properties combined with low heat endurance. Such combination of properties makes impossible the simple transfer of the existing technologies for classic materials working to considered new class. At the same time, the existing tools cannot assure the specified quality of tooled products at the current productivity and tool life. Aim: The aim of this research is to increase the process efficiency of diamond drilling in composite polymers by developing the new designs of diamond drill bits. Materials and Methods: One of the most promising directions to solve this problem is the diamond coated abrasive type tool. This paper addresses and classifies the existing types of diamond drill bits according to their application and operation. The literature data analysis of known disadvantages during drilling operation, the quality of surface and joining face was performed. Results: The experimental researches of the author prove the negative meaning of the already known but kept out fact – the drill core blocking. The most important factors and structural features affecting the CFRP drilling process are revealed. The accounting of these factors allowed creating the set of unique designs of diamond drill bits for different purposes. The presented patented models has different allowance distribution schemes and cutting forces, thus satisfy the mechanical requirements of quality, productivity, tool life and hole geometry in the tooling of the specified material class.

  5. An Industry/DOE Program to Develop and Benchmark Advanced Diamond Product Drill Bits and HP/HT Drilling Fluids to Significantly Improve Rates of Penetration



    A deep drilling research program titled 'An Industry/DOE Program to Develop and Benchmark Advanced Diamond Product Drill Bits and HP/HT Drilling Fluids to Significantly Improve Rates of Penetration' was conducted at TerraTek's Drilling and Completions Laboratory. Drilling tests were run to simulate deep drilling by using high bore pressures and high confining and overburden stresses. The purpose of this testing was to gain insight into practices that would improve rates of penetration and mechanical specific energy while drilling under high pressure conditions. Thirty-seven test series were run utilizing a variety of drilling parameters which allowed analysis of the performance of drill bits and drilling fluids. Five different drill bit types or styles were tested: four-bladed polycrystalline diamond compact (PDC), 7-bladed PDC in regular and long profile, roller-cone, and impregnated. There were three different rock types used to simulate deep formations: Mancos shale, Carthage marble, and Crab Orchard sandstone. The testing also analyzed various drilling fluids and the extent to which they improved drilling. The PDC drill bits provided the best performance overall. The impregnated and tungsten carbide insert roller-cone drill bits performed poorly under the conditions chosen. The cesium formate drilling fluid outperformed all other drilling muds when drilling in the Carthage marble and Mancos shale with PDC drill bits. The oil base drilling fluid with manganese tetroxide weighting material provided the best performance when drilling the Crab Orchard sandstone.

  6. Shengli Diamond Bits

    Yang Yukun; Han Tao


    @@ The geologic condition of Shengli Oilfield (SLOF)is complicated and the range of the rock drillability is wide. For more than 20 years,Shengli Drilling Technology Research Institute, in view of the formation conditions of SLOF,has done a lot of effort and obtained many achivements in design,manufacturing technology and field service. Up to now ,the institute has developed several ten kinds of diamond bits applicable for drilling and coring in formations from extremely soft to hard.

  7. Optimization of Deep Drilling Performance--Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

    Alan Black; Arnis Judzis


    This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2002 through September 2002. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit--fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. Accomplishments to date include the following: 4Q 2002--Project started; Industry Team was assembled; Kick-off meeting was held at DOE Morgantown; 1Q 2003--Engineering meeting was held at Hughes Christensen, The Woodlands Texas to prepare preliminary plans for development and testing and review equipment needs; Operators started sending information regarding their needs for deep drilling challenges and priorities for large-scale testing experimental matrix; Aramco joined the Industry Team as DEA 148 objectives paralleled the DOE project; 2Q 2003--Engineering and planning for high pressure drilling at TerraTek commenced; 3Q 2003--Continuation of engineering and design work for high pressure drilling at TerraTek; Baker Hughes INTEQ drilling Fluids and Hughes Christensen commence planning for Phase 1 testing--recommendations for bits and fluids.

  8. Stinger Enhanced Drill Bits For EGS

    Durrand, Christopher J. [Novatek International, Inc., Provo, UT (United States); Skeem, Marcus R. [Novatek International, Inc., Provo, UT (United States); Crockett, Ron B. [Novatek International, Inc., Provo, UT (United States); Hall, David R. [Novatek International, Inc., Provo, UT (United States)


    The project objectives were to design, engineer, test, and commercialize a drill bit suitable for drilling in hard rock and high temperature environments (10,000 meters) likely to be encountered in drilling enhanced geothermal wells. The goal is provide a drill bit that can aid in the increased penetration rate of three times over conventional drilling. Novatek has sought to leverage its polycrystalline diamond technology and a new conical cutter shape, known as the Stinger®, for this purpose. Novatek has developed a fixed bladed bit, known as the JackBit®, populated with both shear cutter and Stingers that is currently being tested by major drilling companies for geothermal and oil and gas applications. The JackBit concept comprises a fixed bladed bit with a center indenter, referred to as the Jack. The JackBit has been extensively tested in the lab and in the field. The JackBit has been transferred to a major bit manufacturer and oil service company. Except for the attached published reports all other information is confidential.


    Paolo Macini


    Full Text Available This paper underlines the importance of the correct drill bit application in horizontal wells. Afler the analysis of the peculiarities of horizontal wells and drainholes drilling techniques, advantages and disadvantages of the application of both roller cone and fixed cutters drill bits have been discussed. Also, a review of the potential specific featuries useful for a correct drill bit selection in horizontal small diameter holes has been highlighted. Drill bits for these special applications, whose importance is quickly increasing nowadays, should be characterised by a design capable to deliver a good penetration rate low WOB, and, at the same time, be able to withstand high RPM without premature cutting structure failure and undergauge. Formation properties will also determine the cutting structure type and the eventual specific features for additional gauge and shoulder protection.

  10. 国内金刚石工程薄壁钻台架对比钻进实验研究%Drilling Contrast Experiment Study of Domestic Diamond Engineering Thin-Walled Drill Bit

    邓福铭; 王博; 邓雯丽; 周小彦; 赵烨; 刘波; 张红林


    Service life and drilling efficiency are the important measurement indexes of the performance of diamond engineering thin-walled drill bit.Reinforced concrete drilling contrast experiments between engineering thin-walled drill bit manufactured by new tech-nique and a well known domestic product by conventional hot-pressing technique have been conducted.Result shows that the quantity of drill hole of the 1# drill bit manufac-tured by new technique is 94,and the abrasive resistance of it is 5 1.6% higher than that of the most durable procuct in China and their drill rate is similar.This drill bit can be categorized into the high abrasive resistance products;the average drill time of 3 # drill bit is 12.3min/hole and the dirll rate of it is 1 9.5mm/min which is similar to the domestic product of the highest drilling rate while the service life of it is 52% longer which makes is a high efficiency drilling product;the quantity of drill hole of the 2# drill bit is 72 with an average drill rate of 17.7mm/min,its abrasive resistance and drill rate are respectively 29~32% and 26 ~33% higher than those of the most advanced domestic products.The experiments have confirmed that the engineering thin-walled drill bit manufactured by new technique has a nature of high efficiency and long service life which has overcome the incompatibility of abrasive resistance and drill rate of the conventional product of hot-pressing sintering technique.%使用寿命长短以及钻切效率高低是衡量金刚石工程薄壁钻的使用性能优劣的重要指标。采用新工艺制备的金刚石工程薄壁钻与传统热压工艺生产的国内某著名厂家产品进行了钢筋混凝土台架钻切对比实验,结果表明,新工艺制备的1#钻头的钻孔数为94孔,其耐磨性比目前国内使用寿命最长的产品高51.6%,且钻速基本上与之相当,属于高耐磨型产品;3#钻头的平均钻进时间为12.3min/孔,钻速为19.5mm/min,与国内钻速最高的产品相

  11. Application of Diamond Impregnated Bit with Downhole Positive Displacement Drill Motor in Well Wucan 1%孕镶金刚石钻头配合螺杆钻具在乌参1井应用

    吴仲华; 温林荣; 丁世清; 何育光; 赵哲龙; 付晓颖


    With the increasing of the deep and ultra-deep well drilling year by year at home and a-broad,the conventional drilling mode with tri-cone bits and PDC bits has been unable to obtain satisfactory technical and economic indicators in drilling of abrasive formations.At present,the impregnated diamond bit matched with the high speed turbine drill has obtained certain technical effect,but the cost of drilling and pressure difference of the turbine drill for the drilling equipment are high.In this paper,the drilling mode was studied with the impregnated diamond bit matched with downhole positive displacement drill motor which was successfully applied on the well Wu-can1 to drill igneous rock formation.The drilling pressure difference and cost of drilling were re-duced,so the drilling technology and economy effect are perfect.For the future of diamond im-pregnated drill bit development and technology application,the corresponding conclusion and sug-gestion were gave by analyzing and studying of the field application.%随着国内外深井、超深井钻井数量逐年增加,常规牙轮钻头和PDC钻头采用常规钻井方式在可钻性差的研磨性地层中已无法获得令人满意的技术经济指标.目前,孕镶金刚石钻头配合高速涡轮钻具钻该地层取得了一定的技术效果,但是该技术钻井成本高,涡轮钻具压差大对钻井设备要求高.研究的孕镶金刚石钻头配合螺杆钻具钻井模式应用于乌参1井的火成岩地层钻井,取得了降低钻具压差和钻井成本的技术经济效果,并对现场应用进行了分析研究,为今后孕镶金刚石钻头研制和技术推广应用给出建议.


    Robert Radtke; David Glowka; Man Mohan Rai; David Conroy; Tim Beaton; Rocky Seale; Joseph Hanna; Smith Neyrfor; Homer Robertson


    Commercial introduction of Microhole Technology to the gas and oil drilling industry requires an effective downhole drive mechanism which operates efficiently at relatively high RPM and low bit weight for delivering efficient power to the special high RPM drill bit for ensuring both high penetration rate and long bit life. This project entails developing and testing a more efficient 2-7/8 in. diameter Turbodrill and a novel 4-1/8 in. diameter drill bit for drilling with coiled tubing. The high-power Turbodrill were developed to deliver efficient power, and the more durable drill bit employed high-temperature cutters that can more effectively drill hard and abrasive rock. This project teams Schlumberger Smith Neyrfor and Smith Bits, and NASA AMES Research Center with Technology International, Inc (TII), to deliver a downhole, hydraulically-driven power unit, matched with a custom drill bit designed to drill 4-1/8 in. boreholes with a purpose-built coiled tubing rig. The U.S. Department of Energy National Energy Technology Laboratory has funded Technology International Inc. Houston, Texas to develop a higher power Turbodrill and drill bit for use in drilling with a coiled tubing unit. This project entails developing and testing an effective downhole drive mechanism and a novel drill bit for drilling 'microholes' with coiled tubing. The new higher power Turbodrill is shorter, delivers power more efficiently, operates at relatively high revolutions per minute, and requires low weight on bit. The more durable thermally stable diamond drill bit employs high-temperature TSP (thermally stable) diamond cutters that can more effectively drill hard and abrasive rock. Expectations are that widespread adoption of microhole technology could spawn a wave of 'infill development' drilling of wells spaced between existing wells, which could tap potentially billions of barrels of bypassed oil at shallow depths in mature producing areas. At the same time, microhole

  13. Improved Hardfacing for Drill Bits and Drilling Tools

    Sue, Albert; Sreshta, Harry; Qiu, Bao He


    New flame spray hardfacing, DSH (DuraShell® Steel Hardfacing, US patent pending), was developed to improve thermal conductivity, abrasion wear, and erosion resistance for subterranean drilling application. The materials consisted of spherical cast WC/W2C and Ni-Si-B alloy powders. The hardfacing compositions were tailored for various processes such as flame spray and laser cladding. Typically, the hardfacing comprised hard tungsten carbide particles being uniformly distributed in a tough Ni-alloy matrix. The hardness of WC/W2C exceeded 2300 Hv.3 and that of Ni-alloy matrix varied from about 400 to 700 Hv.3. High- and low-stress abrasion resistances of these hardfacing materials were characterized and compared to the conventional hard coatings of cast WC/W2C and Ni-Cr-Si-B-Fe. The increase in thermal, wear, and erosion resistances of the hardfacing improved the durability of PDC (polycrystalline diamond compact) steel body bit and drilling tools and their cost-effective performance. Several case studies of DSH hardfacings on drill bits were described.

  14. Influence of Preferred Orientation on the Performance of Brazing Diamond Core Drill Bit%择优取向对钎焊金刚石薄壁钻性能影响

    杨合丹; 刘一波; 陈哲; 刘胜


    Brazing diamond core drill bit is a type of high-performance superhard material drilling tool which adopts the vacuum brazing technology.In view of the inherent feature of drilling tools,preferred orientation has been adopted for abrasive on the top and com-bined crystal edges of (1 1 1)and (1 10)face has been taken as blade edge of the diamond. This type of drill has a sharp Cutting-edge,smooth chip evacuation and less friction heat and presents high drilling efficiency and long service life.The actual drilling test shows that service life of preferred orientationФ6 and Ф32mm drill bits is almost doubled com-pared to conventional drill bit and the average drilling rate has been improved by over 50% with a very smooth drilling performance;service life of preferred orientationФ32mm has been increased by over 30% compared to uniform bit and the drilling stability of them is similar.%钎焊金刚石薄壁钻是一种采用真空钎焊技术进行的高性能超硬材料钻削工具。根据钻削工具的固有特征,将顶部磨料择优取向,取金刚石岀刃点为(111)面与(110)面结合晶棱,在钻削过程中刃口锋利,排屑顺畅,摩擦生热少,显示出极高的钻进效率和使用寿命。通过实际钻进验证可知:择优取向Φ6小钻头寿命比普通钻头提高接近1倍,平均钻速提高50%以上,并且钻进非常平稳;择优取向Φ32mm 常规钻头寿命比普通钻头提高1倍以上,平均钻速提高50%以上,并且钻进非常平稳;择优取向Φ32mm 常规钻头寿命比均布钻头提高30%以上,钻进平稳性相当。


    Robert Radtke


    The manufacture of thermally stable diamond (TSP) cutters for drill bits used in petroleum drilling requires the brazing of two dissimilar materials--TSP diamond and tungsten carbide. The ENDURUS{trademark} thermally stable diamond cutter developed by Technology International, Inc. exhibits (1) high attachment (shear) strength, exceeding 345 MPa (50,000 psi), (2) TSP diamond impact strength increased by 36%, (3) prevents TSP fracture when drilling hard rock, and (4) maintains a sharp edge when drilling hard and abrasive rock. A novel microwave brazing (MWB) method for joining dissimilar materials has been developed. A conventional braze filler metal is combined with microwave heating which minimizes thermal residual stress between materials with dissimilar coefficients of thermal expansion. The process results in preferential heating of the lower thermal expansion diamond material, thus providing the ability to match the thermal expansion of the dissimilar material pair. Methods for brazing with both conventional and exothermic braze filler metals have been developed. Finite element modeling (FEM) assisted in the fabrication of TSP cutters controllable thermal residual stress and high shear attachment strength. Further, a unique cutter design for absorbing shock, the densification of otherwise porous TSP diamond for increased mechanical strength, and diamond ion implantation for increased diamond fracture resistance resulted in successful drill bit tests.

  16. Diamond Drilling Specification Manual and Course Outline.

    British Columbia Dept. of Education, Victoria.

    This publication presents the standards required of a person practicing diamond drilling in western Canada and provides an outline for teaching the skills and knowledge. It is divided into two parts. The Diamond Drilling Specification Manual establishes the levels of skill and knowledge required in the four certified levels of diamond drilling.…

  17. Research on Abrasion of Diamond Impregnated Bit in Drilling Bomb-proof Ceramic%防弹陶瓷孔加工中金刚石钻头的磨损研究

    高超; 袁军堂; 郑雷


    通过防弹陶瓷孔的加工实验,对烧结金刚石钻头的磨损状况进行研究.分析钻头唇面的磨损变相及打滑现象,指出内外径金刚石承受的切削载荷差异是造成钻头唇面磨损变相的主要原因;打滑现象则是由于出露的金刚石磨损过快,胎体的磨损不能与之匹配造成的.根据磨损状况,提出改变金刚石品级、浓度分布、水口总宽度等改善磨损变相的措施以及采用弱包镶、改善胎体耐磨性、优化唇面和水口形状、控制冷却液流量等防止打滑的措施.该研究对优化防弹陶瓷加工工具设计,提高防弹陶瓷的加工效率和加工质量具有一定的参考价值.%With drilling experiments of bomb-proof ceramic, abrasion status of diamond impregnated bits was studied. Rim distortion and bits slipping were observed and analyzed. The conclusion are that difference of loads upon the diamond between inner diameter and external diameter is the principal cause for the rim distortion of bits and the mismatch between wearing speed of working diamond and that of the matrix is the cause for slipping. According to the abrasion status, a number of enhanced measures were proposed to overcome the rim distortion, such as changing grade of diamond, optimizing diamond concentration distribution, and changing the total width of water discharges; and measures were adopted to prevent slipping, such as decreasing bonding strength, improving abrasion endurance of the matrix, optimizing the shapes of rim and water discharges and controlling the flow of cooling liquid. It provides reference for optimizing design of the tools for bomb-proof ceramic processing and improving its processing efficiency and quality.

  18. Development of Diamond-Coated Drills


    Compared with the sintered polycrystalline diamond, the deposited thin film diamond has the great advantage on the fabrication of cutting tools with complex geometries such as drills. Because of their low costs for fabrication equipment and high performance on high speed machining non-ferrous metals and alloys, metal-compound materials, and hard brittle non-metals, diamond-coated drills find great potentialities in the commercial application. However, the poor adhesion of the diamond film on the substrate...

  19. Drilling of bone: a robust automatic method for the detection of drill bit break-through.

    Ong, F R; Bouazza-Marouf, K


    The aim of this investigation is to devise a robust detection method for drill bit break-through when drilling into long bones using an automated drilling system that is associated with mechatronic assisted surgery. This investigation looks into the effects of system compliance and inherent drilling force fluctuation on the profiles of drilling force, drilling force, drilling between successive samples and drill bit rotational speed. It is shown that these effects have significant influences on the bone drilling related profiles and thus on the detection of drill bit break-through. A robust method, based on a Kalman filter, has been proposed. Using a modified Kalman filter, it is possible to convert the profiles of drilling force difference between successive samples and/or the drill bit rotational speed into easily recognizable and more consistent profiles, allowing a robust and repeatable detection of drill bit break-through.

  20. Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling

    TerraTek, A Schlumberger Company


    The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill 'faster and deeper' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energy and loads. The significance of the 'ultra-high rotary speed drilling system' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm - usually well below 5,000 rpm. This document provides the progress through two phases of the program entitled 'Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling' for the period starting 30 June 2003 and concluding 31 March 2009. The accomplishments of Phases 1 and 2 are summarized as follows: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance (see Black and Judzis); (2) TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed; (3) TerraTek concluded small-scale cutting performance tests; (4

  1. Heat Generation During Bone Drilling: A Comparison Between Industrial and Orthopaedic Drill Bits.

    Hein, Christopher; Inceoglu, Serkan; Juma, David; Zuckerman, Lee


    Cortical bone drilling for preparation of screw placement is common in multiple surgical fields. The heat generated while drilling may reach thresholds high enough to cause osteonecrosis. This can compromise implant stability. Orthopaedic drill bits are several orders more expensive than their similarly sized, publicly available industrial counterparts. We hypothesize that an industrial bit will generate less heat during drilling, and the bits will not generate more heat after multiple cortical passes. We compared 4 4.0 mm orthopaedic and 1 3.97 mm industrial drill bits. Three types of each bit were drilled into porcine femoral cortices 20 times. The temperature of the bone was measured with thermocouple transducers. The heat generated during the first 5 drill cycles for each bit was compared to the last 5 cycles. These data were analyzed with analysis of covariance. The industrial drill bit generated the smallest mean increase in temperature (2.8 ± 0.29°C) P industrial bit generated less heat during drilling than its orthopaedic counterparts. The bits maintained their performance after 20 drill cycles. Consideration should be given by manufacturers to design differences that may contribute to a more efficient cutting bit. Further investigation into the reuse of these drill bits may be warranted, as our data suggest their efficiency is maintained after multiple uses.

  2. Retrieving Drill Bit Seismic Signals Using Surface Seismometers

    Linfei Wang; Huaishan Liu; Siyou Tong; Yanxin Yin; Lei Xing; Zhihui Zou; Xiugang Xu


    Seismic while drilling (SWD) is an emerging borehole seismic imaging technique that uses the downhole drill-bit vibrations as seismic source. Without interrupting drilling, SWD technique can make near-real-time images of the rock formations ahead of the bit and optimize drilling operation, with reduction of costs and the risk of drilling. However, the signal to noise ratio (SNR) of surface SWD-data is severely low for the surface acquisition of SWD data. Here, we propose a new method to retrieve the drill-bit signal from the surface data recorded by an array of broadband seismometers. Taking advantages of wavefield analysis, different types of noises are identified and removed from the surface SWD-data, resulting in the significant improvement of SNR. We also optimally synthesize seis-mic response of the bit source, using a statistical cross-coherence analysis to further improve the SNR and retrieve both the drill-bit direct arrivals and reflections which are then used to establish a reverse vertical seismic profile (RVSP) data set for the continuous drilling depth. The subsurface images de-rived from these data compare well with the corresponding images of the three-dimension surface seis-mic survey cross the well.

  3. PDC (polycrystalline diamond compact) bit research at Sandia National Laboratories

    Finger, J.T.; Glowka, D.A.


    From the beginning of the geothermal development program, Sandia has performed and supported research into polycrystalline diamond compact (PDC) bits. These bits are attractive because they are intrinsically efficient in their cutting action (shearing, rather than crushing) and they have no moving parts (eliminating the problems of high-temperature lubricants, bearings, and seals.) This report is a summary description of the analytical and experimental work done by Sandia and our contractors. It describes analysis and laboratory tests of individual cutters and complete bits, as well as full-scale field tests of prototype and commercial bits. The report includes a bibliography of documents giving more detailed information on these topics. 26 refs.

  4. Assessing the efficiency of carbide drill bits and factors influencing their application to debris-rich subglacial ice

    Yang, Cheng; Jiang, Jianliang; Cao, Pinlu; Wang, Jinsong; Fan, Xiaopeng; Shang, Yuequan; Talalay, Pavel


    When drilling into subglacial bedrock, drill operators commonly encounter basal ice containing high concentrations of rock debris and melt water. As such conditions can easily damage conventional ice drills, researchers have experimented with carbide, diamond, and polycrystalline diamond compact drill bits, with varying degrees of success. In this study, we analyzed the relationship between drilling speed and power consumption for a carbide drill bit penetrating debris-rich ice. We also assessed drill load, rotation speed, and various performance parameters for the cutting element, as well as the physical and mechanical properties of rock and ice, to construct mathematical models. We show that our modeled results are in close agreement with the experimental data, and that both penetration speed and power consumption are positively correlated with drill speed and load. When used in ice with 30% rock content, the maximum penetration speed of the carbide bit is 3.4 mm/s with a power consumption of ≤0.5 kW, making the bit suitable for use with existing electromechanical drills. Our study also provides a guide for further research into cutting heat and equipment design.

  5. Methods to ensure optimal off-bottom and drill bit distance under pellet impact drilling

    Kovalyov, A. V.; Isaev, Ye D.; Vagapov, A. R.; Urnish, V. V.; Ulyanova, O. S.


    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rock for various purposes. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The paper presents the survey of methods ensuring an optimal off-bottom and a drill bit distance. The analysis of methods shows that the issue is topical and requires further research.

  6. Methods to ensure optimal off-bottom and drill bit distance under pellet impact drilling

    Kovalev, Artem Vladimirovich; Isaev, Evgeniy Dmitrievich; Vagapov, A. R.; Urnish, V. V.; Ulyanova, Oksana Sergeevna


    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rock for various purposes. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The paper presents the surve...

  7. Geothermal COMPAX drill bit development. Final technical report, July 1, 1976-September 30, 1982

    Hibbs, L.E. Jr.; Sogoian, G.C.; Flom, D.G.


    The objective was to develop and demonstrate the performance of new drill bit designs utilizing sintered polycrystalline diamond compacts for the cutting edges. The scope included instrumented rock cutting experiments under ambient conditions and at elevated temperature and pressure, diamond compact wear and failure mode analysis, rock removal modeling, bit design and fabrication, full-scale laboratory bit testing, field tests, and performance evaluation. A model was developed relating rock cutting forces to independent variables, using a statistical test design and regression analysis. Experiments on six rock types, covering a range of compressive strengths from 8 x 10/sup 3/ psi to 51 x 10/sup 3/ psi, provided a satisfactory test of the model. Results of the single cutter experiments showed that the cutting and thrust (penetration) forces, and the angle of the resultant force, are markedly affected by rake angle, depth of cut, and speed. No unusual force excursions were detected in interrupted cutting. Wear tests on two types of diamond compacts cutting Jack Fork Sandstone yielded wear rates equivalent at high cutting speeds, where thermal effects are probably operative. At speeds below approx. 400 surface feet per minute (sfm), the coarser sintered diamond product was superior. 28 refs., 235 figs., 55 tabs.

  8. Decision-fusion-based automated drill bit toolmark correlator

    Jones, Brett C.; Press, Michael J.; Guerci, Joseph R.


    This paper describes a recent study conducted to investigate the reproducibility of toolmarks left by drill bits. This paper focuses on the automated analysis aspect of the study, and particularly the advantages of using decision fusion methods in the comparisons. To enable the study to encompass a large number of samples, existing technology was adapted to the task of automatically comparing the test impressions. Advanced forensic pattern recognition algorithms that had been developed for the comparison of ballistic evidence in the DRUGFIRETM system were modified for use in this test. The results of the decision fusion architecture closely matched those obtained by expert visual examination. The study, aided by the improved pattern recognition algorithm, showed that drill bit impressions do contain reproducible marks. In a blind test, the DRUGFIRE pattern recognition algorithm, enhanced with the decision fusion architecture, consistently identified the correct bit as the source of the test impressions.

  9. Nozzle assembly for an earth boring drill bit

    Madigan, J. A.


    A nozzle assembly for an earth boring drill bit of the type adapted to receive drilling fluid under pressure and having a nozzle bore in the bottom thereof positioned closely adjacent the well bore bottom when the bit is in engagement therewith with the bore having inner and outer portions. The nozzle assembly comprises a generally cylindrical nozzle member of abrasion and erosion resistant material, selected from a plurality of such members, each being of the same outer diameter but having passaging therein of different cross-sectional area. The nozzle member is adapted to be fitted in the inner portion of the nozzle bore in sealing relationship therewith for forming a first seal for the nozzle assembly. The nozzle assembly further comprises a locknut, separate from the nozzle member, for detachbably securing the nozzle member in the nozzle bore, formed at least in part of an abrasion and erosion resistant material. The locknut has a threaded side wall engageable with the outer portion of the nozzle bore, and an aperture therethrough for enabling a stream of drilling fluid from the nozzle member to flow therethrough and being so configured in section as to receive a tool for turning the lockout to install it in and remove it from the nozzle bore.


    Alan Black; Arnis Judzis


    The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rock cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology


    Alan Black; Arnis Judzis


    The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rock cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology

  12. Effect of bit wear on hammer drill handle vibration and productivity.

    Antonucci, Andrea; Barr, Alan; Martin, Bernard; Rempel, David


    The use of large electric hammer drills exposes construction workers to high levels of hand vibration that may lead to hand-arm vibration syndrome and other musculoskeletal disorders. The aim of this laboratory study was to investigate the effect of bit wear on drill handle vibration and drilling productivity (e.g., drilling time per hole). A laboratory test bench system was used with an 8.3 kg electric hammer drill and 1.9 cm concrete bit (a typical drill and bit used in commercial construction). The system automatically advanced the active drill into aged concrete block under feed force control to a depth of 7.6 cm while handle vibration was measured according to ISO standards (ISO 5349 and 28927). Bits were worn to 4 levels by consecutive hole drilling to 4 cumulative drilling depths: 0, 1,900, 5,700, and 7,600 cm. Z-axis handle vibration increased significantly (pvibration did not increase further with bits worn more than 1900 cm of cumulative drilling depth. Neither x- nor y-axis handle vibration was effected by bit wear. The time to drill a hole increased by 58% for the bit with 5,700 cm of cumulative drilling depth compared to a new bit. Bit wear led to a small but significant increase in both ISO weighted and unweighted z-axis handle vibration. Perhaps more important, bit wear had a large effect on productivity. The effect on productivity will influence a worker's allowable daily drilling time if exposure to drill handle vibration is near the ACGIH Threshold Limit Value. ([1]) Construction contractors should implement a bit replacement program based on these findings.

  13. Purpose-built PDC bit successfully drills 7-in liner equipment and formation: An integrated solution

    Puennel, J.G.A.; Huppertz, A.; Huizing, J. [and others


    Historically, drilling out the 7-in, liner equipment has been a time consuming operation with a limited success ratio. The success of the operation is highly dependent on the type of drill bit employed. Tungsten carbide mills and mill tooth rock bits required from 7.5 to 11.5 hours respectively to drill the pack-off bushings, landing collar, shoe track and shoe. Rates of penetration dropped dramatically when drilling the float equipment. While conventional PDC bits have drilled the liner equipment successfully (averaging 9.7 hours), severe bit damage invariably prevented them from continuing to drill the formation at cost-effective penetration rates. This paper describes the integrated development and application of an IADC M433 Class PDC bit, which was designed specifically to drill out the 7-in. liner equipment and continue drilling the formation at satisfactory penetration rates. The development was the result of a joint investigation There the operator and bit/liner manufacturers shared their expertise in solving a drilling problem, The heavy-set bit was developed following drill-off tests conducted to investigate the drillability of the 7-in. liner equipment. Key features of the new bit and its application onshore The Netherlands will be presented and analyzed.

  14. Annual Report: Support Research for Development of Improved Geothermal Drill Bits

    Hendrickson, R.R.; Winzenried, R.W.; Jones, A.H.; Green, S.J.


    The work reported herein is a continuation of the program initiated under DOE contract E(10-1)-1546* entitled "Program to Design and Experimentally Test an Improved Geothermal Bit"; the program is now DOE Contract EG-76-C-1546*. The objective of the program has been to accelerate the commercial availability of a tolling cutter drill bit for geothermal applications. Data and experimental tests needed to develop a bit suited to the harsh thermal, abrasive, and chemical environment of the more problematic geothermal wells, including those drilled with air, have been obtained. Efforts were directed at the improvement of both the sealed (lubricated) and unsealed types of bits. The unsealed bit effort included determination of the rationale for materials selection, the selection of steels for the bit body, cutters, and bearings, the selection of tungsten carbide alloys for the friction bearing, and preliminary investigation of optimized tungsten carbide drilling inserts. Bits build** with the new materials were tested under stimulated wellbore conditions. The sealed bit effort provided for the evaluation of candidate high temperature seals and lubricants, utilizing two specially developed test apparatus which simulate the conditions found in a sealed bit operating in a geothermal wellbore. Phase I of the program was devoted largely to (1) the study of the geothermal environment and the failure mechanisms of existing geothermal drill bits, (2) the design and construction of separate facilities for testing both drill-bit seals and full-scale drill bits under simulated geothermal drilling conditions, and (3) fabrication of the MK-I research drill bits from high-temperature steels, and testing in the geothermal drill-bit test facility. The work accomplished in Phase I is reported in References 1 through 9. In Phase II, the first generation experimental bits were tested in the geothermal drill-bit test facility. Test results indicated that hardness retention at temperature

  15. Technique for evaluating antiwear properties of lubricant grease for GN and GNU drill bits

    Gubarev, A.S.; Butovets, V.V.; Dyachenko, Yu.P.; Krasnokutskaya, M.Ye.; Nedbaylyuk, P.Ye.; Oparin, V.A.; Yeremenko, V.F.


    A technique has been developed for determining under laboratory conditions the antiwear characteristics for lubricant grease used for drill bit supports models GN and GNU. A satisfactory coincidence of test results of lubricants USsA and Uniol-1 has been derived using the given technique, as well as satisfactory results for the drill bits operating in industrial conditions.

  16. Apparatus for measuring weight, torque and side force on a drill bit

    Maron, R.


    This patent describes an apparatus for measuring at least one load applied to a drill bit during the drilling of a well. It comprises: drillstring sub means adapted to be connected in a drillstring above the drill bit; a pair of diametrically opposite openings extending only partially through the wall of the sub from an outer surface of the sub means; plug means in each of the openings. The plug means cooperating with the openings to define an atmospheric chamber means in each of the openings; and weight sensor means in each of the opening for generating an output in response to at least the parameter of weight on the drill bit.

  17. 电镀钻头中金刚石的选用原则%Selection Principles of Diamond for Electroplated Bit



      金刚石是电镀钻头主要的钻进和切削元件,其性能的好坏对钻头的工作效率和使用寿命有着直接的影响。要充分了解金刚石的性能,掌握并利用各种检测手段,才能合理选择出性价比高,又能满足钻头需要的金刚石。主要对金刚石的性能和检测方法以及电镀钻头中如何选用金刚石进行了介绍。%Diamond is the main drilling and cutting elements of electroplated bit, its properties have direct impacts on the working efficiency and the service life of drill bit.The full understanding of diamond properties and all kinds of detection means are necessary for reasonably selecting the diamond with high performance -price ratio to satisfy the requirements of bits.The paper mainly introduces the diamond properties, the detection means and how to select diamond.

  18. Apparatus for measuring weight, torque and side force on a drill bit

    Maron, R.


    This patent describes an apparatus for measuring at least one load applied to a drill bit during the drilling of a well, including: drill string sub means adapted to be connected in a drill string above the drill bit; hole means for defining a pair of diametrically opposite through-hole means in the wall of the sub; plug means in each of the hole means, the plug means cooperating with the through hole means to define an atmospheric chamber means in each of the through hole means; ring means in the centerbore of the drillstring sub; fastener means for connecting the plug means to the annular ring means; weight sensor means in each of the through hole means for generating an output in response to at least the parameter of weight on the drill bit.

  19. Design and testing of coring bits on drilling lunar rock simulant

    Li, Peng; Jiang, Shengyuan; Tang, Dewei; Xu, Bo; Ma, Chao; Zhang, Hui; Qin, Hongwei; Deng, Zongquan


    Coring bits are widely utilized in the sampling of celestial bodies, and their drilling behaviors directly affect the sampling results and drilling security. This paper introduces a lunar regolith coring bit (LRCB), which is a key component of sampling tools for lunar rock breaking during the lunar soil sampling process. We establish the interaction model between the drill bit and rock at a small cutting depth, and the two main influential parameters (forward and outward rake angles) of LRCB on drilling loads are determined. We perform the parameter screening task of LRCB with the aim to minimize the weight on bit (WOB). We verify the drilling load performances of LRCB after optimization, and the higher penetrations per revolution (PPR) are, the larger drilling loads we gained. Besides, we perform lunar soil drilling simulations to estimate the efficiency on chip conveying and sample coring of LRCB. The results of the simulation and test are basically consistent on coring efficiency, and the chip removal efficiency of LRCB is slightly lower than HIT-H bit from simulation. This work proposes a method for the design of coring bits in subsequent extraterrestrial explorations.

  20. Seismic Prediction While Drilling (SPWD): Seismic exploration ahead of the drill bit using phased array sources

    Jaksch, Katrin; Giese, Rüdiger; Kopf, Matthias


    In the case of drilling for deep reservoirs previous exploration is indispensable. In recent years the focus shifted more on geological structures like small layers or hydrothermal fault systems. Beside 2D- or 3D-seismics from the surface and seismic measurements like Vertical Seismic Profile (VSP) or Seismic While Drilling (SWD) within a borehole these methods cannot always resolute this structures. The resolution is worsen the deeper and smaller the sought-after structures are. So, potential horizons like small layers in oil exploration or fault zones usable for geothermal energy production could be failed or not identified while drilling. The application of a device to explore the geology with a high resolution ahead of the drill bit in direction of drilling would be of high importance. Such a device would allow adjusting the drilling path according to the real geology and would minimize the risk of discovery and hence the costs for drilling. Within the project SPWD a device for seismic exploration ahead of the drill bit will be developed. This device should allow the seismic exploration to predict areas about 50 to 100 meters ahead of the drill bit with a resolution of one meter. At the GFZ a first prototype consisting of different units for seismic sources, receivers and data loggers has been designed and manufactured. As seismic sources four standard magnetostrictive actuators and as receivers four 3-component-geophones are used. Every unit, actuator or geophone, can be rotated in steps of 15° around the longitudinal axis of the prototype to test different measurement configurations. The SPWD prototype emits signal frequencies of about 500 up to 5000 Hz which are significant higher than in VSP and SWD. An increased radiation of seismic wave energy in the direction of the borehole axis allows the view in areas to be drilled. Therefore, every actuator must be controlled independently of each other regarding to amplitude and phase of the source signal to

  1. Advances in developing the air-lift drilling technology. Concept of a portal drilling rig - trial of a steerable shaft drilling bit

    Weber, W.


    The Federal Minister of Research and Technology is supporting a project of Wirth GmbH to develop a new drilling rig suitable for drilling deep shafts from the surface through ground of almost any condition, from unstable formations to solid rock. The development of such drilling rig is based on the blind drilling method with air-assisted reverse circulation. - Various concepts of drilling rigs have been developed in accordance with different planning stages of a combined RD-project. Based on the experience of an extensive R and D program a steerable vertical drilling bit has been developed by which deviations from the vertical can be positively corrected. The prototype of this steerable bit with a diameter of 2.1 m has been tested successfully while drilling a well with a depth of more than 200 m in an open pit coal mine.

  2. Follow the drill

    Fitch-Roy, O. [Dando Drilling International (United Kingdom)


    The paper discusses modern drilling techniques with which Dando Drilling has been involved. It describes equipment supplied to opencast coal operations in Kalimantan, Borneo. These include polycrystalline diamond drill bits, flushing media, rig drilling controls and other specialised equipment. 3 photos.

  3. High power laser-mechanical drilling bit and methods of use

    Grubb, Daryl L.; Kolachalam, Sharath K.; Faircloth, Brian O.; Rinzler, Charles C.; Allen, Erik C.; Underwood, Lance D.; Zediker, Mark S.


    An apparatus with a high power laser-mechanical bit for use with a laser drilling system and a method for advancing a borehole. The laser-mechanical bit has a beam path and mechanical removal devices that provide for the removal of laser-affected rock to advance a borehole.

  4. Field Study of Drilling Bits Performance Optimization Using a Computer Model.

    Oriji, A. Boniface


    Full Text Available One of the major problems facing drilling operations is the performance of the drilling Bits. The ability of the Bit to crush the rock and the removal of the crushed rock from the wellbore effectively. It is necessary to understand the fundamental difference in Bit design for different rock textures because many variables tend to affect Bit optimization, particularly the type of formations, economics and Bit selection. However, the cost of drilling a well has a considerable effect on the selection and the design of a particular Bit, therefore this paper focuses on the development of a model that will predict future Bit performance and optimization for actual well design and construction. The variables to optimize Bit performance provide means of handling cost estimation hence the model becomes more realistic and dynamic in its application. The input variables and control factors for this model are stretched to minimize cost and maximize performance. The cost per foot and the break even calculations were done using data from the reference well X14 and also the evaluation well X35 from a field-X in the Niger Delta region. A Visual Basic dot Net program model was developed, tested and validated with the real field data to know its accuracy. The model interface shows the detailed application of the Bits in validating the data to provide the equivalent results for the five different Bits. Each set of the Bit record was ran separately on the software and the results for each application developed for comparison. In the software, data application were grouped into two distinct methods namely; rentals method and historical method. Under the rentals method, data were uploaded into the software and ran to generate results while the historical method was basically used for model prediction. The breakeven analysis provided a technique for calculating the performance required for an alternative Bit type to match the cost per foot of the current Bit. Based on

  5. Seismic Prediction While Drilling (SPWD: Looking Ahead of the Drill Bit by Application of Phased Array Technology

    Marco Groh


    Full Text Available Geophysical exploration is indispensable for planning deep drilling. Usually 2D- or 3D-seismics investigations are applied and, depending on the resulting geologic model for the underground, the drill site and drilling path are determined. In recent years the focus of exploration has shifted towards small-scale geological structures such as local layers and faults. Depending on the source frequencies and the target depth, 2D- or 3D-seismics from surface cannot always resolve such structures in particular at larger depths. In general, signal frequencies of about 30–70 Hz are typical for surface seismic methods. The deeper and smaller the sought-after structures are, the worse will be the resolution. Therefore, borehole seismic measurements like Vertical Seismic Profile (VSP or Seismic While Drilling (SWD have been developed (Fig. 1. For the VSP method geophones are normally integrated in the borehole, while the seismicsource generates seismic waves at the surface. The SWD method uses the drill bit as the seismic source. Hence, the quality of the seismic signals is highly dependent on the drilled rock and the type of drill bit, but even well-suited rock conditions and adequate drilling may not provide sufficient data quality.

  6. Reflection of drill-string extensional waves at the bit-rock contact.

    Poletto, Flavio; Malusa, Massimo


    Downward propagating extensional waves are partially reflected at the bit-rock contact. The evaluation of the reflection coefficient is important to obtain while drilling information about the acoustic properties of the formations. The scope of this work is to estimate the bit-rock reflection coefficient, assuming a flat drill bit in perfect contact with the formation. Using the low-frequency approximation, which holds when the wavelength is much larger than the lateral dimensions of the borehole, the drill-string is assumed to be a laterally free rod, and the formation an homogeneous and isotropic medium. This work shows that the reflection coefficient of the extensional waves depends, along with the elastic properties of the formation, on the ratio of the cross sections of the drill-string and borehole. The impedance of the drilled rock can be calculated from the measured reflection coefficient, which is related to the amplitude of waves produced in the string and in the formation by a working drill-bit.

  7. Quantum measurement and entanglement of spin quantum bits in diamond

    Pfaff, W.


    This thesis presents a set of experiments that explore the possible realisation of a macroscopic quantum network based on solid-state quantum bits. Such a quantum network would allow for studying quantum mechanics on large scales (meters, or even kilometers), and can open new possibilities for

  8. Quantum measurement and entanglement of spin quantum bits in diamond

    Pfaff, W.


    This thesis presents a set of experiments that explore the possible realisation of a macroscopic quantum network based on solid-state quantum bits. Such a quantum network would allow for studying quantum mechanics on large scales (meters, or even kilometers), and can open new possibilities for appli

  9. Controlling torque and cutting costs: steerable drill bits deliver in Latin America

    Barton, Steve; Garcia, Alexis; Amorim, Dalmo [ReedHycalog, Stonehouse (United Kingdom); Iramina, Wilson [University of Sao Paulo (USP), SP (Brazil); Herrera, Gabriel


    Tool face Control is widely regarded as one of the greatest directional drilling challenges with a Fixed Cutter (FC) drill bit on a Steerable Motor assembly. Tool face offset is proportional to the torque generated by the bit, and by nature, FC bits are capable of generating high levels of torque. If large changes in downhole torque are produced while drilling, this will cause rotation of the drill string, and loss of tool face orientation. This results in inefficient drilling and increases risk of bit and downhole tool damage. This paper examines the effect of various FC drill bit components to determine the key design requirements to deliver a smooth torque response and an improved directional performance. Included is a review of the results from comprehensive laboratory testing to determine the effectiveness of a number of different configurations of removable Torque Controlling Components (TCC). These, in combination with specific cutting structure layouts, combine to provide predictable torque response while optimized for high rates of penetration. In addition, unique gauge geometry is disclosed that was engineered to reduce drag and deliver improved borehole quality. This gauge design produces less torque when sliding and beneficial gauge pad interaction with the borehole when in rotating mode. Field performance studies from within Latin America clearly demonstrate that matching TCC, an optimized cutting structure, and gauge geometry to a steerable assembly delivers smooth torque response and improved directional control. Benefits with regard to improved stability are also discussed. Successful application has resulted in significant time and cost savings for the operator, demonstrating that Stability and Steerability improvements can be achieved with an increase in penetration rate. (author)

  10. The Questions of the Dynamics of Drilling Bit on the Surface of Well Bottom

    Burievich, Toshov Javohir


    The purpose of this study was to investigate the dynamics of drilling bit on the well bottom as a function of their geometrical parameters. The frame of this method for this study includes former existed objective data on the unstable drilling devices as cantilever suspension. Research methods and calculation results are as follows: square coverage by tools blade working in different rotation regime; radius of the inscribed and circumscribed circle which leads to introduce and prospectively and solve problems on process optimization of mining rock at drilling the well bottom.

  11. 国际油气井钻头进展概述(二)——FuseTek融合钻头与Pexus组合钻头%International Advancement of Drilling Bits for Oil and Gas Well ( 2 ) —FuseTek Bit and Pexus Hybrid Bit



    NOV公司2013年向市场推出FuseTek融合钻头. 它将PDC钻头的高钻速与孕镶金刚石钻头的耐磨性结合于一体,适宜于钻进中硬—坚硬、高研磨性地层. FuseTek钻头已广泛应用于刚果、厄瓜多尔、中国、哥伦比亚等国家. 应用表明,该新型组合钻头比PDC钻头或牙轮钻头钻进效率提高许多,工作寿命增加1~3倍或更多. Shear Bits公司于2014年推出Pexus组合钻头. 该钻头广泛应用于加拿大冰川冰碛物钻进. 地层上部硬卵砾石层利用可转动硬质合金齿钻进,下部软砂岩与页岩则运用PDC碎岩. 整个冰碛物地层用一个Pexus钻头一钻到底. 所述3类组合式钻头(含Kymera钻头)对于未来实现"一个钻头,一口井"的目标有重要意义.%FuseTek bit, a PDC+Impregnated diamond hybrid bit, launched by NOV in 2013.It is suitable for drilling me-dium-hard to hard and abrasion formations.The FuseTek bits were widely used in Congo, Ecuador, China, Colombia, etc., Applications have shown that the FuseTek bits could increase the ROP obviously and bit life 1-3 times or more com-pared with PDC bit or roller cone bit .Pexus hybrid bit, a PDC+Carbide hybrid bit, launched by Shear Bits in 2014, which used extensively in Western Canada to drill glacial till, comprised of a hard top layer of boulders, drilled by rotary carbide element and a soft bottom layer of sand and shales drilled by PDC cutters.The whole interval can be drilled in one run with one Pexus bit.Those three types of hybrid bits are significant for realization of"one bit, one well" in the future.

  12. Methodology for appraising anti-wear properties in plastic lubricants for GN- and GNU-type drilling bits

    Gubarev, A.S.; Butovets, V.V.; Dyachenko, Yu.P.; Krasnyukutskaya, M.Ye.; Nedbaylyuk, P.Ye.; Oparin, V.A.; Yeremenko, V.F.


    A methodology is developed for the laboratory appraisal of anti-wear properties in plastic lubricants for GN- and GNU-type drilling bits. Industrial test results for USsA and Uniol-1 lubricants used with GNU-series drilling bits corresponded closely to the laboratory results.

  13. Tribological tests of wear-resistant coatings used in the production of drill bits of horizontal and inclined drilling

    Maslov, A. L.; Markova, I. Yu; Zakharova, E. S.; Polushin, N. I.; Laptev, A. I.


    It is known that modern drilling bit body undergoes significant abrasive wear in the contact area with the solid and the retracted cuttings. For protection of the body rationally use wear-resistant coating, which is welded directly to the body of bit. Before mass use of the developed coverings they need to be investigated by various methods that it was possible to characterize coatings and on the basis of the obtained data to perform optimization of both composition of coatings and technology. Such methods include microstructural studies tribological tests, crack resistance and others. This work is devoted to the tribological tests of imported brand of coatings WokaDur NiA and and domestic brand of coating HR-6750 (both brands manufactured by Ltd “Oerlikon Metco Rus”), used to protect the bit body from abrasive wear.

  14. Modeling of the egress of a drilling liquid from the nozzle of a drill bit with Ansys Fluent

    Smorkalov, D. V.; Tyutyaev, A. V.; Shterenber, A. M.; Gorshkalev, A. A.


    A 3D model was built for the cylindrical outer nozzle of a drill bit which was in an immersed space at the distance of four diameters from the formation. A tetrahedral lattice was applied to the space filled with liquid, and a hexahedral lattice was applied to a section of the 3D model which imitated the rock (formation). A boundary layer was built near the walls. As a result of the calculations, the impact of the jet on the rock has been demonstrated, and it is similar to the impact of a drilling liquid jet on the bottom of a well during drilling. Distribution of the pressures, as well as the vector of velocities, the change in the volume ratio of a rock and the depth of penetration of the jet have been understood.

  15. Effect of Boron-Doped Diamond Interlayer on Cutting Performance of Diamond Coated Micro Drills for Graphite Machining

    Zhiming Zhang


    Full Text Available Thin boron doped diamond (BDD film is deposited from trimethyl borate/acetone/hydrogen mixture on Co-cemented tungsten carbide (WC-Co micro drills by using the hot filament chemical vapor deposition (HFCVD technique. The boron peak on Raman spectrum confirms the boron incorporation in diamond film. This film is used as an interlayer for subsequent CVD of micro-crystalline diamond (MCD film. The Rockwell indentation test shows that boron doping could effectively improve the adhesive strength on substrate of as deposited thin diamond films. Dry drilling of graphite is chosen to check the multilayer (BDD + MCD film performance. For the sake of comparison, machining tests are also carried out under identical conditions using BDD and MCD coated micro drills with no interlayer. The wear mechanism of the tools has been identified and correlated with the criterion used to evaluate the tool life. The results show that the multilayer (BDD + MCD coated micro drill exhibits the longest tool life. Therefore, thin BDD interlayer is proved to be a new viable alternative and a suitable option for adherent diamond coatings on micro cutting tools.

  16. Study on Particular Coring Bit for Lunar Soil Drilling%月球钻探取心特种钻头研制与试验

    李大佛; 雷艳; 许少宁


      对月壤形成过程和物质组成进行了介绍,并将实际月壤基本物理力学指标与CUG-1型模拟月壤和普通干砂进行对比,认为在月球钻探取样过程中可能遇到具有一定胶结强度的硬质团块。为保证钻探取样顺利进行,需要研制月球钻探用特种取心PDC钻头。基于PDC钻头的碎岩机理,对钻头的负前角、旁通角、出露高度、钻头保径和PDC切削齿的钎焊工艺分别进行了设计,并对钻杆和钻头装配体在钻进过程中的受力过程进行有限元分析。最后,采用所设计的特种取心PDC钻头进行岩石干钻试验,试验结果表明,该钻头能钻进可钻性级别小于或等于6级的岩石,能满足月球钻探需要。%Forming process and composition of lunar soil were introduced in this paper, and the actual lunar soil physical and mechanical indexes were compared with and simulated CUG-1 lunar soil and normal dry sand, it was suggested that hard clods with certain cementing strength might be encountered in lunar coring drilling.To ensure the successful lunar co-ring drilling, a special polycrystalline diamond compact (PDC) coring bit should be developed.Based on the breaking rock mechanism of PDC bit, the negative rake angle, bypass angle, exposure height, gauge protection of PDC bit and brazing technologies of PDC cutters were designed respectively;and finite element analysis was made on the force of bit and drill stem assembly during drilling process.At last, the dry drilling test was made by special designed PDC bit, it indicated that the bit would be effective when rock drillability was less than or equal toⅥ, and it could stratify the requirements for lunar soil drilling.

  17. Detection of bit location by acoustic emission technique in horizontal directional drilling. Kojo sakushin koho ni okeru bit ichi no AE ho ni yoru hyotei

    Abe, M.; Niitsuma, H. (Tohoku Univ., Sendai (Japan). Faculty of Engineering); Sugimori, S. (Tohoku Univ., Sendai (Japan). Grauduate School); Nakajima, T. (NKK Corp., Tokyo (Japan))


    The accuracy of the bit location in the excavation of pilot holes with horizontal drilling technique must be kept less than several tens of centimeters. Such an accuracy is hard to be achieved by the existing controlling technology. The depth of the bit tip can be measured comparatively accurately using a clinometer and the like. The azimuth meter, gyroscope, underground radar, locator, etc. are used for the detection of azimuth of the bit, but every one of them has its own problem. Therefore, new measuring methods to be used in combination with the conventional methods are required which can cover up the shortcomings of the conventional methods. Acoustic emission (AE) technique is employed for the detection of the bit location, and the accompanying problems as well as detecting performance are investigated. It is used for the measurement in the drilling test performed at the reclaimed land on the premises of Keihin ironworks of NKK Corp. In connection with the detection of the bit location in horizontal pilot drilling, a study is made on the zone detection technique for AE signals generated by the bit when striking ground and those generated during drilling. 7 refs., 17 figs., 1 tab.

  18. 印制板用微型钻头及微孔钻削进展%Development of PCB micro drill bit and micro drilling

    付连宇; 郭强


    尽管激光钻孔在印制板(PCB)钻孔中应用得越来越广,但是利用微型钻头在机械钻机上进行的机械钻孔仍然是最重要的PCB钻孔方式。顺应PCB微孔的发展趋势,微型钻头直径越来越小,新型钻头结构不断出现,微钻头性能不断提高,微钻头涂层技术逐步成熟,微孔钻削的研究不断深入,推动着PCB技术的发展。本文即对微钻头及微孔钻削的进展进行总结,对微钻头和微孔钻削的趋势进行展望。%Although laser drilling plays more and more important role in PCB microvia drilling, mechanical drilling by using micro drill bit on drilling machine still dominates the PCB micro hole drilling methods. With the development trend of PCB micro hole, the micro drill bit becomes smaller and smaller, the performances of micro drill bit becomes better and better, coated micro drill bits becomes more and more popular and the comprehensive studies of micro hole drilling are reported. These developments are reviewed in this paper and the development trend of micro drill bit and micro drilling are pointed.


    Radenko Drakulić


    Full Text Available Two optical methods based on laser and video technology and digital signal and image processing techniques - Laser Doppler velocimetry (LDV and Particle image velocimetry (PIV were applied in highly accurate fluid flow measurement. Their application in jet velocity measurement of flows through drilling bit nozzles is presented. The role of nozzles in drilling technology together with procedures and tests performed on their optimization are reviewed. In addition, some experimental results for circular nozzle obtained both with LDV and PIV are elaborated. The experimental set-up and the testing procedure arc briefly discussed, as well as potential improvements in the design. Possible other applications of LDV and PIV in the domain of petroleum engineering are suggested (the paper is published in Croatian.

  20. Ground truth : vertical seismic profile data enables geophysicists to image ahead of the drill bit

    Eaton, S. [SR ECO Consultants Inc., Calgary, AB (Canada)


    This paper presented a new technology which makes it possible to obtain a vertical seismic profile (VSP) of a wellbore via a wireline tool. Downhole seismic is of extreme importance in cases when there is a discrepancy between the geology in the well and surface seismic data and when drilling has gone deeper than the prognosis for oil or gas. Once VSP data are interpreted, the decision can be made to either abandon the well or sidetrack it to an optimum target position. The VSP data give the geophysicist the opportunity to recalibrate the processing of conventional 2-D or 3-D surface seismic data while drilling. Crucial assumptions for the velocity fields can be tested. This new technology links geology and geophysics, making it possible to quantify subsurface reservoir parameters and to obtain downhole seismic that provides a higher frequency and spatial resolution than conventional surface seismic surveys. The energy source for downhole seismic is situated at ground level. The signal then travels down into the earth where it is recorded in the subsurface by a vertical array of geophones situated in the wellbore. Some of the signal travels past the bottom of the borehole, through the underlying layers that still have to be drilled. Geophysicists with PanCanadian Petroleum Ltd. and Baker Atlas state that a VSP gives ground truth because the acquired data enables the geophysicist to image ahead of the drill bit. VSP is the ultimate tool in interval velocity and time to depth conversion. Downhole seismic has 25 per cent higher frequencies than surface seismic. The technology has been successfully used by Talisman Energy Inc., to drill Foothills wells in the Monkman Pass area of northeastern British Columbia. VSP data can be used to predict formation pressures, porosities, lithologies or rock types, and fluid content. The technology has been useful in the drilling of hostile holes offshore Sable Island in Nova Scotia where wells can cost up to $30 million. VSPs are

  1. Experimental and numerical study of drill bit drop tests on Kuru granite

    Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko


    This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

  2. Processing of diamond enhanced cemented tungsten carbide insert for rock drilling

    LIU Bao-chang; SUN You-hong; ZHANG Zu-pei


    This paper introduced the structure, component and sintering procedure of the Diamond/WC-Co composite insert fabricated by high pressure and high temper ature (HPHT) method as well as by hot pressing method. In HPHT method, to avoid breakage and delamination of the diamond layer, two transition layers were added between the most outer diamond layer and the WC-Co body. The transition layers compensate for differences in thermal expansion coefficient and elastic modulus of diamond layer and WC-Co substrate. Thus reduces the residual stress induced by cooling the inserts from sintering temperature to room temperature. In hot pressing method, to decrease sintering temperature so as to protect diamond, an active sintering process which achieved by adding nickel and phosphorus into the starting mixed powder is adopted. To increase the toughness of the inserts to resist breakage, proper amount of rare earth compound, LaNi5 and CeO2, are added into the original mixed powder, too. Laboratory tests indicated that both of the diamond enhanced inserts fabricated by HPHT method and by hot pressing method have relatively high hardness and impact toughness, while their wear resistance is about hundreds of times greater than that of conventional cemented tungsten carbide inserts. The results of field drilling test indicated that the diamond enhanced inserts can meet the demands of rotary percussion drilling.

  3. Development and testing of a Mudjet-augmented PDC bit.

    Black, Alan (TerraTek, Inc.); Chahine, Georges (DynaFlow, Inc.); Raymond, David Wayne; Matthews, Oliver (Security DBS); Grossman, James W.; Bertagnolli, Ken (US Synthetic); Vail, Michael (US Synthetic)


    This report describes a project to develop technology to integrate passively pulsating, cavitating nozzles within Polycrystalline Diamond Compact (PDC) bits for use with conventional rig pressures to improve the rock-cutting process in geothermal formations. The hydraulic horsepower on a conventional drill rig is significantly greater than that delivered to the rock through bit rotation. This project seeks to leverage this hydraulic resource to extend PDC bits to geothermal drilling.

  4. Optimization of Cvd Diamond Coating Type on Micro Drills in Pcb Machining

    Lei, X. L.; He, Y.; Sun, F. H.


    The demand for better tools for machining printed circuit boards (PCBs) is increasing due to the extensive usage of these boards in digital electronic products. This paper is aimed at optimizing coating type on micro drills in order to extend their lifetime in PCB machining. First, the tribotests involving micro crystalline diamond (MCD), nano crystalline diamond (NCD) and bare tungsten carbide (WC-Co) against PCBs show that NCD-PCB tribopair exhibits the lowest friction coefficient (0.35) due to the unique nano structure and low surface roughness of NCD films. Thereafter, the dry machining performance of the MCD- and NCD-coated micro drills on PCBs is systematically studied, using diamond-like coating (DLC) and TiAlN-coated micro drills as comparison. The experiments show that the working lives of these micro drills can be ranked as: NCD>TiAlN>DLC>MCD>bare WC-Co. The superior cutting performance of NCD-coated micro drills in terms of the lowest flank wear growth rate, no tool degradation (e.g. chipping, tool tipping) appearance, the best hole quality as well as the lowest feed force may come from the excellent wear resistance, lower friction coefficient against PCB as well as the high adhesive strength on the underneath substrate of NCD films.

  5. New types of drilling tools fit with PCD elements

    Koníèek Jiøí


    Full Text Available One of the most significant developments in drilling technology over the last years has been the introduction of polycrystalline diamond (PCD as macro-cutting elements in the rotary drill application. This paper gives a summary of core bits and cutter bits, produced by Pramet Šumperk Co., which are fit with these PCD elements. Some results, obtained with these types of cutter bits by drilling in mines of Ostrava-Karviná Basin, are also presented.

  6. Drill bit seismic, vertical seismic profiling, and seismic depth imaging to acid drilling decisions in the Tho Tinh structure Nam Con Son Basin-Vietnam

    Borland, W.; Leaney, W.; Nakanishi, S.; Kusaka, H.


    Rapid deposition in the Nam Con Son Basin during the Miocene resulted in under-compacted shales. These under-compacted shales are often associated with over-pressured formations. As these shales have excess water and tend to be mechanically weak, the safe mud window for drilling the under-compacted interval can be quite narrow. Efficient and safe drilling operations require accurate depth predictions of these over-pressured formations as well a knowledge of the magnitude of the over-pressure. In this paper we describe a technique which combines the best aspects of conventional Vertical Seismic Profiles (VSP) and Reverse Vertical Seismic Profiles (RVSP) to detect under-compacted shales and predict formation pressures to locate drilling hazards below TD. Under-compacted shales with excess water will have a lower acoustic impedance than expected from the compaction trend. Shales that depart from the compaction trend may indicate potential drilling hazards below. Conventional VSPs provide high quality reflection data at discrete intervals in the well, and can be used to accurately predict acoustic impedance below the bit. This acoustic impedance is then interpreted to provide both the location (in time and depth) of the drilling hazard and the mud weight necessary to contain it. The two-way time estimate of the hazard location is usually quite accurate but the depth estimate is less certain due to the estimation error in formation velocities below TD. The RVSP using the drill bit as a source, provides a continuous time versus depth relationship while drilling. This time versus depth is used to continually update the conventional VSP depth prediction of the drilling hazard and thus provide the most accurate depth of the hazard prior to its penetration. It is also used to update a depth-indexed display of existing surface seismic at the wellsite. 10 refs., 22 figs.

  7. Roughnecks, rock bits and rigs : the evolution of oil well drilling technology in Alberta, 1883-1970

    Gow, A.


    This book provides a comprehensive review of the evolving technologies related to oil and gas exploration in the province of Alberta. Oil well drilling technology evolved significantly during the era of conventional oil exploration in the province, from 1883 through 1970. Technologies such as drill bits and power sources were developed largely through trial and error to meet the specific needs of individuals working in the oilfield. The competence and resolve to innovate by drill crews was told through accounts of evolution in drilling processes and equipment, along with personal accounts of those who worked on the rigs. The technology of the oilfield was placed into context with a summary of the history and geology of oil and gas in Alberta. The book also presents a considerate view of events in relation to those who invested in the industry, carried out research drilling and serviced the exploration industry. The first part of the book provides the background to the oil and gas industry. Part 2 examines the earliest technology, the standard cable tool drilling rig, the combination rig and some associated developments in drilling. The third part focuses on the rotary drilling rig and the final part outlines the types of challenges faced by the drillers and the hazards of working on Alberta's rigs. refs., tabs., figs.

  8. Research on Diamond Enhanced Tungsten Carbide Composite Button


    At the present, the cutters used in button bits and rock bits are mainly cobalt tungsten carbide in our country. Because of its low abrasive resistance, the bit service life and drilling efficiency was very low when the hard and extremely hard formations were being drilled. Owing to its high abrasive resistance, the diamond composite material is widely used in drilling operations. However, its toughness against impact is too low to be used in percussion drilling, only can it be used in rotary drilling. In ...

  9. Downhole drilling motors: technical review. Final report

    Maurer, W.C.; McDonald, W.J.; Nixon, J.D.; Matson, L.W.


    Dyna-Drills and turbodrills are used primarily for directional drilling where it is critical that the drillpipe not be rotated. These tools are not widely used for straight-hole drilling because of problems with bearing failures, low power outputs, low bit pressures, and high rotary speeds. The high rotary speeds produce bit bearing failures in 10 to 15 h, compared to 100 to 200 h life at lower rotary speeds. The technology now exists to develop reliable high-torque motors which will operate roller bits at speeds of 150 to 250 RPM and diamond bits at speeds of 400 to 800 RPM for periods of 100 to 200 hours. Sealed bearing assemblies which allow the bearings to operate in lubricant are being developed. These improved bearings allow bits to operate at the high bit weights needed for optimum drilling. Improved drilling motors can reduce drilling costs to significantly increase the number of wells drilled per drilling rig per year. Now, this is increasingly important because of the drilling rig shortage developing in this country. At least ten companies are working on the development of improved drilling motors and it is likely that several of these new motors will become commercially available within the next 2 to 3 years. Several companies are working on the development of improved high speed roller bits for use on drilling motors. The development of these high speed bits should significantly increase the use of drilling motors since bit bearing failures are a major problem when drilling with motors. The development of reliable, high-speed STRATAPAX bits should also increase motor useage since these bits drilling most effectively at rotary speeds of 300 to 500 RPM.

  10. Drill bit seismic, vertical seismic profiling, and seismic depth imaging to aid drilling decisions in the Tho Tinh structure, Nam Con Son basin, Vietnam

    Borland, W.; Hayashida, N.; Kusaka, H.; Leaney, W.; Nakanishi, S.


    This paper reviews the problem of overpressure, a common reason for acquiring look-ahead VSPs, and the seismic trace inversion problem, a fundamental issue in look-ahead prediction. The essential components of intermediate VSPs were examined from acquisition through processing to inversion, and recently acquired real data were provided, which were indicative of the advances being made toward developing an exclusive high resolution VSP service. A simple interpretation method and an end product of predicted mud weight versus depth were also presented, which were obtained from the inverted acoustic impedance and empirical relations. Of paramount importance in predicting the depth to a target was the velocity function used below the intermediate TD. The use of empirical or assumed density functions was an obvious weak link in the procedure. The advent of real-time time-depth measurements from drill bit seismic allowed a continuously updated predicted target depth below the present bit depth. 8 refs., 7 figs.

  11. CVD diamond for electronic devices and sensors


    Synthetic diamond is diamond produced by using chemical or physical processes. Like naturally occurring diamond it is composed of a three-dimensional carbon crystal. Due to its extreme physical properties, synthetic diamond is used in many industrial applications, such as drill bits and scratch-proof coatings, and has the potential to be used in many new application areas A brand new title from the respected Wiley Materials for Electronic and Optoelectronic Applications series, this title is the most up-to-date resource for diamond specialists. Beginning with an introduction to the pr

  12. PDC bit selection to drill the Brazilian pre-salt heterogeneous carbonates; Selecao de broca PDC para a perfuracao dos carbonatos heterogeneos do pre-sal brasileiro

    Lima, Araken Dumont Ramos; Tocantins, Joao Pedro Tourinho [Schlumberger, Rio de Janeiro, RJ (Brazil)


    The well drilling operation to access the oil reserves of the Brazilian pre-salt find their highest challenge in the rock reservoir, which is formed from organic limestone and other sediments, and it can have different heterogeneous features that are hostile to drilling. Those features such as the silica nodules increase the rock formation strength and abrasiveness that together with the PDC bit vibrations generated during the rock cutting reduce the life of the cutting structure to a few meters. Because of these conditions, the development of more stable bits, with very low lateral and torsional vibration levels and with more strength PDC, has been one oil industry challenges to drill the pre-salt limestone with silica. This paper aims to present a dynamic comparative analysis between three PDC bits, called BR1, BR2 and BR3, of different generations, selected to drill a well design in a limestone heterogeneous and homogeneous (without silica nodules). This analysis was performed with dynamic three dimensional finite elements software, which considers the interaction between the bit cutter structure and the rock to be drilled, used to design bits, reamers and BHA (Bottom Hole Assembly). (author)

  13. Apparatus and method for situ sharpening of bore hole bits

    Bridwell, H.C.


    An impregnated diamond core bit is sharpened at the bottom of a borehole, the bit being secured to the outer barrel of coring apparatus attached to a tubular drill string. A sharpener is releasably mounted in the lower end of an inner core barrel lowered through the drill string into the outer barrel and latched thereto, with the sharpener projecting below the lower end of the core bit. The sharpener has nozzles for discharging abrasive material pumped through the sharpener against the drilling face of the bit to sharpen the same, whereupon the coring operation can be effected in the usual manner, the core releasing the sharpener from the inner barrel and pushing it upward along and within the inner barrel as the core is formed. The sharpener is rtrieved with the inner barrel upon release of the latter from the outer barrel and its upward removal through the drill string to the top of the borehole. (29 claims)

  14. Analysis of Efficiency of Drilling of Large-Diameter Wells With a Profiled Wing Bit / Badania Efektywności Wiercenia Studni Wielkośrednicowych Świdrem Skrawającym z Profilowanymi Skrzydłami

    Macuda, Jan


    In Poland all lignite mines are dewatered with the use of large-diameter wells. Drilling of such wells is inefficient owing to the presence of loose Quaternary and Tertiary material and considerable dewatering of rock mass within the open pit area. Difficult geological conditions significantly elongate the time in which large-diameter dewatering wells are drilled, and various drilling complications and break-downs related to the caving may occur. Obtaining higher drilling rates in large-diameter wells can be achieved only when new cutter bits designs are worked out and rock drillability tests performed for optimum mechanical parameters of drilling technology. Those tests were performed for a bit ø 1.16 m in separated macroscopically homogeneous layers of similar drillability. Depending on the designed thickness of the drilled layer, there were determined measurement sections from 0.2 to 1.0 m long, and each of the sections was drilled at constant rotary speed and weight on bit values. Prior to drillability tests, accounting for the technical characteristic of the rig and strength of the string and the cutter bit, there were established limitations for mechanical parameters of drilling technology: P ∈ (Pmin; Pmax) n ∈ (nmin; nmax) where: Pmin; Pmax - lowest and highest values of weight on bit, nmin; nmax - lowest and highest values of rotary speed of bit, For finding the dependence of the rate of penetration on weight on bit and rotary speed of bit various regression models have been analyzed. The most satisfactory results were obtained for the exponential model illustrating the influence of weight on bit and rotary speed of bit on drilling rate. The regression coefficients and statistical parameters prove the good fit of the model to measurement data, presented in tables 4-6. The average drilling rate for a cutter bit with profiled wings has been described with the form: Vśr= Z ·Pa· nb where: Vśr- average drilling rate, Z - drillability coefficient, P

  15. Analysis and Testing of Load Characteristics for Rotary-Percussive Drilling of Lunar Rock Simulant with a Lunar Regolith Coring Bit

    Peng Li


    Full Text Available Based on an optimized lunar regolith coring bit (LRCB configuration, the load characteristics of rotary-percussive drilling of lunar rock simulant in a laboratory environment are analyzed to determine the effects of the drilling parameters (the rotational velocity, the penetration rate, and the percussion frequency on the drilling load. The process of rotary drilling into lunar rock using an LRCB is modeled as an interaction between an elemental blade and the rock. The rock’s fracture mechanism during different stages of the percussive mechanism is analyzed to create a load forecasting model for the cutting and percussive fracturing of rock using an elemental blade. Finally, a model of the load on the LRCB is obtained from the analytic equation for the bit’s cutting blade distribution; experimental verification of the rotary-impact load characteristics for lunar rock simulant with different parameters is performed. The results show that the penetrations per revolution (PPR are the primary parameter influencing the drilling load. When the PPR are fixed, increasing the percussion frequency reduces the drilling load on the rock. Additionally, the variation pattern of the drilling load of the bit is in agreement with that predicted by the theoretical model. This provides a research basis for subsequent optimization of the drilling procedure and online recognition of the drilling process.

  16. Status and Applications of Diamond and Diamond-Like Materials: An Emerging Technology


    produced for cutting tools, wire - drawing dies, and well-drilling bits. Polycrystalline pieces up to about 50 mm in diameter, usually on a carbide base... wire - drawing dies, coatings for drills, and bearing surfaces. It may also be possible to employ diamond coatings as impact-protection coatings for...their respective stability regions at HPHT conditions. Tools for cutting, drilling, sawing, and wire drawing have been common in the marketplace since

  17. Analysis of bit-rock interaction during stick-slip vibrations using PDC cutting force model

    Patil, P.A.; Teodoriu, C. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE


    Drillstring vibration is one of the limiting factors maximizing the drilling performance and also causes premature failure of drillstring components. Polycrystalline diamond compact (PDC) bit enhances the overall drilling performance giving the best rate of penetrations with less cost per foot but the PDC bits are more susceptible to the stick slip phenomena which results in high fluctuations of bit rotational speed. Based on the torsional drillstring model developed using Matlab/Simulink for analyzing the parametric influence on stick-slip vibrations due to drilling parameters and drillstring properties, the study of relations between weight on bit, torque on bit, bit speed, rate of penetration and friction coefficient have been analyzed. While drilling with the PDC bits, the bit-rock interaction has been characterized by cutting forces and the frictional forces. The torque on bit and the weight on bit have both the cutting component and the frictional component when resolved in horizontal and vertical direction. The paper considers that the bit is undergoing stick-slip vibrations while analyzing the bit-rock interaction of the PDC bit. The Matlab/Simulink bit-rock interaction model has been developed which gives the average cutting torque, T{sub c}, and friction torque, T{sub f}, values on cutters as well as corresponding average weight transferred by the cutting face, W{sub c}, and the wear flat face, W{sub f}, of the cutters value due to friction.

  18. 基于 PCA-SVDD 方法的钻头异常钻进识别%Drill bit abnormal drilling condition recognition based on PCA-SVDD

    刘刚; 刘闯; 夏向阳; 裴重潋; 蔡鹏; 赵少伟


    为了快速识别钻头异常钻进情况,达到实时监测丛式井防碰需求,根据钻头振动信号的幅值归一化频数统计特征,提出一种基于 PCA-SVDD 的钻头异常钻进识别模型。提取钻头正常钻进信号的每一帧数据的归一化频数特征,该特征与波形的真实幅值大小无关,适合不同工作情况,将提取的特征应用 PCA 方法降维处理得到钻头正常钻进的特征向量作为训练样本,建立基于 PCA-SVDD 的钻头异常钻进诊断模型。通过现场数据检验,证明该方法可以有效、快速地识别钻头异常钻进情况。%In order to detect drill bit abnormal drilling condition quickly and monitor cluster wells in real time,a drill bit abnormal drilling recognition model was built based on PCA-SVDD,according to the statistical characteristics of normalized amplitude-frequency of drill bit vibration signals.The normalized frequency characteristics of drill bit normal drilling signals,unrelated to the real amplitude value of signal wave shape,were extracted,they were suitable for different working conditions.The dimension of the extracted characteristics was reduced with PCA to acquire the eigen-vectors of signals under normal working conditions,these eigen-vectors were taken as training samples in the process of SVDD,a PCA-SVDD drill bit abnormal drilling diagnostic model was established.The results of real test data showed that the proposed method can detect drill bit abnormal drilling condition effectively.

  19. Design of Auger Drill Bit Design Database System%旋挖钻头设计制造数据库系统设计

    马红月; 郑现磊; 张西坤; 崔鹤田; 高淑芳; 范志杰


    Rotary digging is commonly used pile construction method in China, because of the properties of high efficiency, low noise, environmental protection and high quality of hole forming, rotary drilling rig has wide range of construction.Dif-ferent types of bit should be chosen to meet different construction formations.By the rational selection and the use of auger drill bits, the construction technology and application field of auger drill can be enriched and broadened.The establishment of auger drill bit database system can provide data support for design, manufacture and type selection of auger drill bit to meet the increasingly complex construction requirements.This paper introduces the design of database system of design and manufacture of auger drill bit and the application.%旋挖钻进施工目前是我国常用的桩工施工工法。旋挖钻机施工由于效率高、噪声低、环保、成孔质量高等特点,施工范围极广。但由于施工地层各不相同,需要选择不同形式的钻头来满足不同的施工要求。合理地选择和使用旋挖钻头,能够丰富旋挖钻机的施工工艺,拓宽旋挖钻机的施工领域。建立旋挖钻头数据库系统,为旋挖钻头的设计、制造、选型提供数据支撑,满足日益复杂的施工要求。本文介绍了旋挖钻头设计制造数据库系统的设计及应用情况。

  20. On the performances and wear of WC-diamond like carbon coated tools in drilling of CFRP/Titanium stacks

    Boccarusso, L.; Durante, M.; Impero, F.; Minutolo, F. Memola Capece; Scherillo, F.; Squillace, A.


    The use of hybrid structures made of CFRP and titanium alloys is growing more and more in the last years in the aerospace industry due to the high strength to weight ratio. Because of their very different characteristics, the mechanical fastening represent the most effective joining technique for these materials. As a consequence, drilling process plays a key role in the assembly. The one shot drilling, i.e. the contemporary drilling of the stack of the two materials, seems to be the best option both in terms of time saving and assembly accuracy. Nevertheless, due to the considerable different machinability of fiber reinforced plastics and metallic materials, the one shot drilling is a critical process both for the holes quality and for the tools wear. This research was carried out to study the effectiveness of new generation tools in the drilling of CFRP/Titanium stacks. The tools are made of sintered grains of tungsten carbide (WC) in a binder of cobalt and coated with Diamond like carbon (DLC), and are characterized by a patented geometry; they mainly differ in parent WC grain size and binder percentage. Both the cutting forces and the wear phenomena were accurately investigated and the results were analyzed as a function of number of holes and their quality. The results show a clear increase of the cutting forces with the number of holes for all the used drilling tools. Moreover, abrasive wear phenomena that affect initially the tools coating layer were observed.

  1. Performance evaluation of reactive direct current unbalanced magnetron sputter deposited nanostructured TiN coated high-speed steel drill bits

    Harish C Barshilia; K S Rajam


    The stainless steels, in general, are considered to be difficult-to-machine materials. In order to machine these materials the surface of the tool is generally coated with physical vapour deposition (PVD) hard coatings such as titanium nitride (TiN), titanium aluminum nitride (TiAlN), etc. The adhesion is of vital importance for the performance of tools coated with PVD coatings. Proper surface treatments (in situ and ex situ) are required to achieve highly adherent PVD coatings on tools. We have deposited nanostructured TiN coatings on high-speed steel (HSS) drill bits and mild steel substrates using an indigenously built semi-industrial fourcathode reactive direct current (d.c.) unbalanced magnetron sputtering system. Various treatments have been given to the substrates for improved adhesion of the TiN coatings. The process parameters have been optimized to achieve highly adherent thick good quality TiN coatings. These coatings have been characterized using X-ray diffraction, nanoindentation and atomic force microscopy techniques. The performance of the coated HSS drill bits is evaluated by drilling a 13 mm thick 304 stainless steel plate under wet conditions. The results show significant improvement in the performance of the TiN coated HSS drill bits.

  2. Drilling successful from ROV Ventana

    Stakes, Debra S.; McFarlane, James A. R.; Holloway, G. Leon; Greene, H. Gary

    Cores of granite and deformed sediment from the walls of Monterey Canyon were successfully recovered from December 30 to 31, 1992, by Monterey Bay Aquarium Research Institute's (MBARI) Remotely Operated Vehicle (ROV) Ventana using a small-diameter, double-barrel drill with a diamond bit. This HSTR (Holloway-Stakes-Tengdin-Rajcula) drill was developed to drill cores horizontally from sulfide/sulfate walls of active black smokers. The drill was first successfully used by the submersible Alvin in October 1991 to drill into massive sulfide chimneys, on the Juan de Fuca Ridge (Eos, June 30, 1992, p. 273), and it was subsequently used with equal success on the chalcopyrite-rich chimneys from 21°N and 9°N on the East Pacific Rise. The recent December dives, however, marked the first time that drilling has ever been attempted from the smaller ROV and the first time coring into the harder igneous rock substrate has been attempted.

  3. Comparative testing of drill bits used at the KHS-2 coal plow of Messrs. Halbach-Braun. Vergleichsversuche der am Hobel KHS-2 der Firma Halbach-Braun eingesetzten Hobelmeissel

    Klich, A.; Krauze, K.; Podsiadlo, A.; Ptak, J. (Akademia Gorniczo-Hutnicza, Krakow (Poland))


    The KHS-2 coal plows of Messrs. Halbach-Braun used in the Polish black coal mine 'Brzeszcze' frequently experienced chain rupture, destruction of the guiding devices for discs and heavy wear of intermediate and ground drill bits that stemmed from the too short service-life of cutting devices and high winning resistance at individual drill bits. In order to remedy these drawbacks, the cutting devices were modified. With the original German, and the modified Polish drill bits, both laboratory and operating tests were carried out. The experimental results reported clearly conform to expectations on the design and technological modifications. The modified drill bits not only have a longer service life because they can be regenerated several times; they also consume less energy. (MOS).

  4. Plastic Drill Bits

    Roman, Harry T.


    This article encourages students to think multidimensionally and in a multidisciplinary fashion with this challenge, and choose a team that can support this kind of thinking. Presented is a challenge in which a major home improvement company makes tools and accessories for use by experienced and new homeowners. This company would like to provide…

  5. Optimisation of the geometry of the drill bit and process parameters for cutting hybrid composite/metal structures in new aircrafts

    Isbilir, Ozden

    to model material and failure behaviour of CFRP. The effects of process parameters on drilling outputs have been investigated and compared with the experimental results. The influences of drill bit geometries have been simulated in this study..

  6. A Sustainable Evaluation of Drilling Parameters for PEEK-GF30

    Rosario Domingo


    Full Text Available This paper presents a study of hole quality and energy consumption in the process of drilling a thermoplastic polymeric material, polyether-ether-ketone, reinforced with 30% glass fibers (PEEK-GF30. PEEK-GF30’s capacity to be machined has focused on turning operations. Studies of drilling involving thermoplastic polymeric materials have considered materials with other types of matrices, or reinforcement. In this study, quantities such as maximum and mean surface roughness, delamination, maximum thrust force, maximum momentum, and energy required during the process were determined for three types of drill bits, and the most influential factors for each variable were identified using an ANOVA multifactor analysis. The highest quality and lowest energy consumption were achieved for a drill bit rotation speed of 7000 rpm and a feed rate of 400 mm/min with a tungsten carbide (WC drill bit coated with titanium aluminum nitride (TiAlN. Although a WC drill bit with a diamond point reduces delamination, the roughness increases, thus, the choice of the drill bit type depends on the roughness allowed. A WC drill bit coated with TiAlN produces a good surface finish that can eliminate subsequent operations and requires less energy; thus, this type of drill bit is the most attractive of the types evaluated.

  7. Drill-rig noise suppression using the Karhunen-Loéve transform for seismic-while-drilling experiment at Brukunga, South Australia

    Sun, Baichun; Bóna, Andrej; Zhou, Binzhong; King, Andrew; Dupuis, Christian; Kepic, Anton


    Diamond-impregnated drill bits are known to be low energy vibration seismic sources. With the strong interference from the drill rig, it is difficult to obtain the drill-bit wavefield with a surface receiver array. To overcome the challenge of surface wave interference generated from the rig for seismic-while-drilling (SWD), we need to separate the rig- and bit-generated signals. To this end, we apply two wavefield separation methods, the Karhunen-Loéve (KL) transform and the f - k filter, and compare their performance. The applicability of these methods is based on the drill rig and drill bit having different spatial positions. While the drill-bit spatial position changes during the process of drilling, the drill rig remains stationary. This results in the source wavefields from the drill rig and the drill-bit having different characteristics, and allows us to separate and extract the drill-bit signal. We use a synthetic model to compare the KL transform and f - k filter. Both techniques are robust when the noise wavefield has consistent amplitude moveout. However, for changing amplitudes, such as the rig noise, which has an unrepeatable wavefield due to power amplitude variation, we show that the KL transform performs better in such situations. We also show the results of signal analysis of the SWD experiment data acquired from Brukunga, South Australia. We demonstrate the feasibility of the KL transform in separating the coherent noises from the stationary drill rig in a hard rock drilling environment, particularly emphasising the suppression of the surface and direct waves from the rig. The results show that drill-rig noise can be effectively suppressed in the correlation domain.

  8. 磨料射流联合机械齿提高硬岩钻进效率研究%Combined drilling of hard rock with abrasive water jet and mechanical bit to improve drilling efficiency


    A dense “boss” in the hole bottom by the conventional drilling in the hard rock requires a more efficient drilling technique with slow bit wear, a new kind of hard rock combined drilling method with the abrasive water jet and mechanical bit is developed in this paper. In this method, it is proposed to introduce the abrasive water jet to erode the “boss” for a “pilot hole”, and then the drilling mechan-ism of conventional rotating bit is changed to improve the hard rock drilling efficiency. Meanwhile, the mechanism of the new drilling method to improve drilling efficiency in hard rock was revealed by using fracture mechanics theory and energy conservation principle. Moreover, by designing a hard rock breaking bit and a set of hard rock combined drilling equipment system, a series of comparative expe-riments between the new and conventional techniques were conducted. The results show that the drilling depth has increased by about 63%, the axial force and torque have reduced by about 15% and 20% re-spectively, and the bit wear is reduced significantly.%  针对煤矿中穿硬质岩层钻孔预抽瓦斯时钻进困难这一问题,在理论分析孔底“凸台”的形成是导致传统旋转钻头钻进困难主要原因基础上,提出了磨料射流联合机械齿钻进硬岩新方法,即利用磨料射流强大的冲蚀能力,预先消除“凸台”,形成先导孔,进而改变传统旋转钻头钻岩机理,达到提高硬岩钻进效率目的。利用断裂力学理论与能量守恒原理揭示了磨料射流联合机械齿提高硬岩钻进效率机理。设计发明了一种破碎硬岩钻头,总成了一套联合钻进硬岩实验系统,并完成了一系列新技术与现有技术的对比实验研究。结果表明,相同条件下,钻头钻进效率较现有技术条件提高63%,承受轴向力与扭矩分别下降约15%和20%,钻头磨损明显减轻。

  9. 钎焊金刚石套料钻CFRP制孔研究%Analysis on CFRP Hole Making with Brazed Diamond Core Drill

    徐九华; 牟娟; 陈燕; 傅玉灿; 王伟锋


    The high hardness of carbon fiber in carbon fiber reinforced plastics (CFRP) leads to quick wear, low durability of drills, and poor machining quality in drilling process. Appling brazed diamond core drill to drilling CFRP can improve drill durability and increase machining quality. In order to optimize the setting of diamond grits on core drill, the diamond grits are orderly set to make core drill, and the maximum undeformed chip thickness are changed through changing the diamond quantity. The influences of maximum undeformed chip thickness on thrust force, surface roughness of hole wall and quality of hole entrance and exit are compared under the same machining parameters. The moving model of diamond grits is set up to analyze the forming process of machined surface. The results and analysis show that the drilling quality is influenced by chip storage space and the maximum undeformed chip thickness. If the chip storage space is sufficient, the thrust force decreases and the drilling quality improves with the decreasing maximum undeformed chip thickness.%碳纤维增强复合材料(Carbon fiber reinforced plastics,CFRP)中高硬度碳纤维易加速孔加工钻头的磨损,导致加工质量变差.采用钎焊金刚石套料钻加工CFRP不仅可提高钻头的耐磨性,加工质量也得到了改善.为更好地优化提高套料钻加工性能,试验采用有序排布的金刚石磨粒制作钎焊套料钻,尝试通过改变磨粒数量来调整单颗磨粒切厚大小,对相同工艺参数下不同单颗磨粒切厚对钻削轴向力、孔壁粗糙度以及出入口质量的影响进行了研究.建立了金刚石磨粒的运动模型,并分析了套料钻制孔中已加工表面的形成过程.试验结果与分析表明:制孔质量与容屑空间和单颗磨粒切厚有关.在容屑空间充足的情况下,随着单颗磨粒切厚的减小,轴向力减小,制孔质量提高.

  10. Fabrication of Fe-Based Diamond Composites by Pressureless Infiltration

    Meng Li


    Full Text Available A metal-based matrix is usually used for the fabrication of diamond bits in order to achieve favorable properties and easy processing. In the effort to reduce the cost and to attain the desired bit properties, researchers have brought more attention to diamond composites. In this paper, Fe-based impregnated diamond composites for drill bits were fabricated by using a pressureless infiltration sintering method at 970 °C for 5 min. In addition, boron was introduced into Fe-based diamond composites. The influence of boron on the density, hardness, bending strength, grinding ratio, and microstructure was investigated. An Fe-based diamond composite with 1 wt % B has an optimal overall performance, the grinding ratio especially improving by 80%. After comparing with tungsten carbide (WC-based diamond composites with and without 1 wt % B, results showed that the Fe-based diamond composite with 1 wt % B exhibits higher bending strength and wear resistance, being satisfactory to bit needs.

  11. Drilling subsurface wellbores with cutting structures

    Mansure, Arthur James; Guimerans, Rosalvina Ramona


    A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

  12. Calvarial bone wound healing: a comparison between carbide and diamond drills, Er:YAG and Femtosecond lasers with or without BMP-7.

    Cloutier, Martin; Girard, Bruno; Peel, Sean A F; Wilson, David; Sándor, George K B; Clokie, Cameron M L; Miller, Dayne


    This study compared the healing of 2 laser ablation units, erbium YAG and femtosecond lasers versus conventional mechanical cutting with carbide and diamond drills to explore future applications for bone surgery. The effects of laser or mechanical ablation combined with rhBMP-7 were also investigated. Following defect standardization, a full-thickness circular defect was created on the parietal bones of 160 mice divided into 4 groups: carbide drill, diamond drill, erbium YAG laser, and femtosecond laser. Each of the 4 ablation groups was treated with and without BMP 7. Hard tissue healing was assessed using microcomputerized tomography at 3 and 12 weeks postsurgical time points. The femtosecond laser created wounds that showed slightly delayed bone healing during the observation period when compared with mechanical drilling, although the difference was not statistically significant. The Er:YAG laser showed a healing rate similar to that of the mechanically ablated groups. When BMP 7 was added to the surgical sites, bone wound closure occurred at a similar rate in all test groups. The femtosecond and Er:YAG lasers are 2 laser modalities suitable for bone ablation that are comparable to mechanical instrumentation in terms of bone healing. This study suggested that BMP-7 may be used to enhance bone healing with success regardless of the ablative modality used, whether laser or mechanical drilling. Copyright © 2010 Mosby, Inc. All rights reserved.

  13. A novel method of removal of a broken drill bit in the femoral medullary canal during internal fixation of a type C distal femoral fracture: a case report

    Varatharaj Mounasamy; Pingal Desai; Satya Mallu; Senthil Sambandam


    Breakage of surgical instruments and implants during operative procedures is not uncommon in any surgical discipline.The need for removal and the outcome of leaving the broken instruments and implants in the surgical area have not been described in detail.Few studies have suggested removal if they are lying loosely in the tissues or joint,close to neurovascular structures.Challenges and the amount of time spent in the retrieval of broken instruments and implants are well known among surgeons,so most choose to leave them in situ.We reported a novel method of retrieval of a broken drill bit in the femoral medullary canal during internal fixation of a type C distal femoral fracture.

  14. Influence of rare-earth modification on the properties of 18KhN2MFL steel for drill bit roller cutters

    Evseev, P.P.; Zhirkin, Y.N.


    This paper examines the influence of rare-earth metals on the behavior of nonmetallic inclusions, the physical and mechanical properties, the critical transformation points, and the macrostructure of 18KhN2MFL cast steel used for the production of drill bit roller cutters with a diameter of 295 mm and more. The nonmetallic inclusion investigation results showed that for 18KhN2MFL steel deoxidized with aluminum, two types of inclusions are characteristic: sharp angled alumina inclusions and globular manganese sulfides with hardnesses of 2200 HV and 190 HV, respectively. The wear resistance tests showed that the rare-earth-metal-modified steel possesses higher abrasive wear resistance as compared with the unmodified; the relative wear resistance of such steel increases by 14-23%.

  15. A novel method of removal of a broken drill bit in the femoral medullary canal during internal fixation of a type C distal femoral fracture: a case report

    Mounasamy Varatharaj


    Full Text Available 【Abstract】 Breakage of surgical instruments and implants during operative procedures is not uncommon in any surgical discipline. The need for removal and the out-come of leaving the broken instruments and implants in the surgical area have not been described in detail. Few studies have suggested removal if they are lying loosely in the tis-sues or joint, close to neurovascular structures. Challenges and the amount of time spent in the retrieval of broken in-struments and implants are well known among surgeons, so most choose to leave them in situ. We reported a novel method of retrieval of a broken drill bit in the femoral medul-lary canal during internal fixation of a type C distal femoral fracture. Key words: Fracture fixation, internal; Femoral fractures; Surgical instruments

  16. Simulation on hydraulic performance of two kinds of diamond core bit with different crown%两种不同唇面结构的取心金刚石钻头水力性能的模拟分析

    刘志义; 段隆臣; 张清


    The software Cfdesign was used for the analysis on flow field simulation of two different kinds of drilling bit. The results showed that, if the waterway design of drilling bit was unreasonable, it could result in the following phenomena: the drilling bit could get eroded locally by the drilling fluid; the return of flow and eddy currents of drilling fluid could occur at the bottom of drilling well; negative pressure could be detected and might result in cavitation corrosion; the direction vector of flow field were diffused and resulted in cross flowing. The simulation results indicated that waterway structure of arc-bottom bit was more reasonable compared with that of flat-bottom bit.%采用计算流体力学软件CFdesign对两种不同结构的钻头,分别进行了水力学性能模拟研究.结果表明,钻头水路结构设计不合理,容易引起下列现象:(1)钻头局部位置受流体冲刷作用强烈;(2)形成井底钻井液的逆向流动和涡流;(3)造成井底流场负压,可能引起气蚀现象;(4)流场流速矢量方向发散,加剧漫流现象.模拟分析的结果表明圆弧型钻头较平底型钻头结构设计更加合理.

  17. Cable-suspended Ice and Bedrock Electromechanical Drill: Design and Tests

    Wang, Rusheng; Talalay, Pavel; Sun, Youhong; Zheng, Zhichuan; Cao, Pinlu; Zhang, Nan; Chen, Chen; Xu, Huiwen; Xue, Hong; Xue, Jun; Yu, Dahui; Fan, Xiaopeng; Hu, Zhengyi; Yang, Cheng; Gong, Da; Liu, Chunpeng; Han, Junjie; Yu, Chengfeng; Hong, Jialing; Wang, Lili


    Directly obtaining the subglacial bedrock samples is one of the most important tasks of Antarctic exploration in the future, which has great significance to research the formation and evolution of the Antarctic ice sheet, research the environment at the junction of the ice and bedrock, and research the geologic structure in Polar Regions. To drill through ice and bedrock, a new modified version of the cable-suspended Ice and Bedrock Electromechanical Drill 'IBED' is designed. IBED drill has modulus construction. The upper part includes four sections: cable termination, slip rings section, antitorque system, electronic pressure chamber. The motor-gear system is differed by rotation speed of the output shaft of the gear-reducer. All modulus contain 3 kW AC3 × 380 V submersible motor. Gear-reducer for drilling in ice lowers the drill bit rotation speed to 100 rpm; gear reducer for subglacial drilling lowers the drill bit rotation speed to 500 rpm. In addition, module for dry core drilling contains vacuum pump for near bottom air reverse circulation instead of liquid-driven pump that is installed into other two variants. The rotation speed of air-driven pump is increased by the gear to 6000 rpm. In modules for drilling with liquid the gear pump is used with capacity of 38-41 L/min and maximal pressure of 0.2 MPa. IBED lower part for drilling in ice consists from two parts: chip chamber for filtration of drilling fluid and collecting chips, and core barrel with the drill bit. The outer/inner diameter of the ice core drill bit is 134/110 mm. Length of the core barrel is 2.5 m. Lower part of the bedrock drill is adapted for coring bedrock and contains standard 2-m length core barrel borrowed from conventional diamond drill string, chip chamber for gravity separation of rock cuttings and dead weights (appr. 200 kg) for increasing of the load on the diamond drill bit. The outer/inner diameters of the diamond bit are 59/41 mm. The IBED drill was tested in order to solve

  18. PDC钻头双管钻探工艺在河南西部铝土矿地层的应用%Application of PDC bit and double tube swivel drilling techniques in west of Henan bauxite strata

    潘广灿; 张金来


    文章分析探讨铝土矿地层钻探工艺,采用常规绳索取芯钻探、普通双管钻探与PDC双管钻探对比进行,钻进中采用常规钻探方法常发生钻具粘附孔壁而产生的卡钻问题,致使钻探效率低,采用PDC钻头双管钻探不仅较好地解决了粘附孔壁而卡钻的问题,而且提高了钻探效率.%In the paper the authors analyzed and discussed the drilling technology in bauxite strata, through the comparation of conventional rope core drilling, normal twin pipe drilling and drilling PDC double. Conventional drilling method could not solve drill hole wall adhesion and sticking problems, often making drilling with low efficiency. While PDC bits and double pipe drilling can better solve the adhesion of the hole wall and the sticking of problems, improving drilling efficiency.

  19. Analysis of hydrologic structures within Mauna Kea volcano using diamond wireline core drilling

    Thomas, D. M.; Haskins, E.


    The Humu'ula Groundwater Research Project was undertaken on the Island of Hawaii in an effort to characterize the hydrologic structures controlling groundwater movement and storage within the dry (~430 mm/year annual rainfall) saddle region between Mauna Loa and Mauna Kea volcanoes. The project drilled a 1764 m, continuously-cored, borehole from an elevation of 1946 m amsl. The shallow stratigraphy consisted of alluvial outwash of clastic debris, of both volcanic and glacial origin, from the upper slopes of Mauna Kea, and was underlain by highly permeable post-shield lavas to depths of a few hundred meters. Below this depth, shield stage lavas were dominated by highly-fractured and permeable pahoehoe lavas and (less common) a'a flows and occasional soil and ash accumulations at flow boundaries. As depths increased below 1000 m, progressive compaction of fragmental material was found at the flow boundaries and, by depths of ~1500 m, much of the void space in the flow boundaries had been collapsed and compacted. Increasing secondary mineralization was observed below about 1000 m depth that was exacerbated by rising temperatures and temperature gradients toward the bottom of the hole. Hydrologic conditions were strikingly different from those predicted by conventional models for ocean islands: the formation was dry down to only ~150 m where the first, thin, perched aquifer was encountered; a second, more substantial, perched aquifer was reached at only ~220 m depth that extended to ~360 m where a sequence of (remarkably thin) perching formations were recovered in the core down to about 420 m where unsaturated rocks were again encountered. Saturated conditions resumed at 550 m depth that continued to the total depth drilled; this latter zone is inferred to be the basal aquifer for Mauna Kea within this region of the island. Our initial analysis of the core suggests that thin, clay-rich, perching formations in the shallow stratigraphic column play a much larger role in

  20. Anniversaries of Innovative Drilling Technologies. Reference Review Program

    Кozhevnikov, А.А.


    Full Text Available Processes of formation of diamond rock cutting tools, namely big diamond drilling crown; small diamond drilling crown; crown equipped with synthetic diamonds; reinforced by composite materials using diamonds are considered. Stages of innovative development of drilling technologies are presented.

  1. Conditions d'apparition et formes de rebond d'un outil de forage tricône Conditions of Appearance and Forms of Lift-Off Dynamics (Bit Bouncing for a Roller Cone Drill Bit

    Putot C.


    caractéristique de cohésion de la roche. Ainsi, et conformément à l'intuition, le rebond se manifestera préférentiellement avec une roche très résistante et une structure souple pour la fréquence envisagée. Des considérations d'efficacité de coupe, liées à la compatibilité plus ou moins grande de la géométrie du cône et de la courbure de l'interface du motif trilobé, sont dégagées et cadrent parfaitement avec une dissymétrie observée sur les enregistrements (Trafor du couple entre maxima et minima ; les phases de décollement et de reprise de contact en cas de rebond sont également compatibles avec les extrema de poids sur outil. The longitudinal vibration mode of the drill string can, in certain drilling conditions, degenerate into bit-bouncing wih periodic separation at the roller bit cone, rock interface; it goes without saying that this behavior must be avoided. In the presence of compact rocks, we are used to associating the lift-off dynamics to the presence of a pattern at the rock-bit interface, known as a bottom hole pattern because of its ternary symmetry. It emerges by a more or less sinusoidal, periodic undulation of the cutting edge. On soft rocks , the speed of the longitudinal vibration phenomenon is more chaotic and is the subject of specific investigations relating dynamics and the expulsion of fragments (Cutclean programme. On hardrocks, the experience proves that the pattern is repeated on each passage of the bit by differentiated erosion of the undulations, without there necessarily being detachment. A general rotation of the interface pattern then occurs, in the order of a few degrees per turn, related the phase shift between cutting effort and undulation. The bounce phenomenon appears especially when there is agreement between the running frequency of the cones --dependent on the rotational speed- and a frequency which is unique to the drilling system. However the phenomenon can also appear a long way from the resonance

  2. Classification system adopted for fixed cutter bits

    Winters, W.J.; Doiron, H.H.


    The drilling industry has begun adopting the 1987 International Association of Drilling Contractors' (IADC) method for classifying fixed cutter drill bits. By studying the classification codes on bit records and properly applying the new IADC fixed cutter dull grading system to recently run bits, the end-user should be able to improve the selection and usage of fixed cutter bits. Several users are developing databases for fixed cutter bits in an effort to relate field performance to some of the more prominent bit design characteristics.

  3. Carbon nanotube reinforced metal binder for diamond cutting tools

    Sidorenko, Daria; Mishnaevsky, Leon; Levashov, Evgeny


    of grain size of the structural constituents of the binder, what in turn leads to the improved simultaneously hardness, Young modulus, plastic extension, bending strength and performances of the metallic binders. Comparing service properties of diamond end-cutting drill bits with and without MWCNT one......The potential of carbon nanotube reinforcement of metallic binders for the improvement of quality and efficiency of diamond cutting wheels is studied. The effect of multi-walled carbon nanotube (MWCNT) reinforcement on the mechanical properties i.e. hardness, Young modulus, strength and deformation...

  4. Integrating straight & swirling jets bit design and its rock breaking characteristics for radial horizontal hole drilling%径向水平钻孔直旋混合射流钻头设计与破岩特性

    廖华林; 李根生; 牛继磊; 黄中伟


    In order to solve the contradiction between borehole diameter and the depth of borehole of high pressure jet drilling in laterally radial horizontal wells, a new type of jet bit design was proposed which integrated both advantages of round jet and swirling jet. The design method was given,and the jet flow structure and its rock breaking characteristics were analyzed in terms of high speed photograph and rock drilling experiments. The results show that the jet formed by the new designed jet bit has both features of round straight jet and swirling jet, with larger hole diameter than a conical round jet bit and deeper depth than a swirling jet bit. Furthermore, many structural parameters of the jet bit affect the rock breaking results. By optimizing jet bit structure configure, hole drilling characteristics could be adjusted. The study can provide a reference for jet bit design in radial horizontal drilling. It is further needed to perform flow field, and rock breaking mechanism analysis to improve the jet utilization efficiency.%为解决高压水射流径向水平钻孔时孔径和孔深相互矛盾的问题,设计了一种兼具直射流和旋转射流特点的直旋混合射流钻头.给出了射流钻头设计方法,通过破岩实验,分析了直旋混合射流钻头结构对其破岩特性的影响.结果表明,直旋混合射流结合了直射流和旋转射流优点,比锥形喷嘴圆直射流扩孔能力强,比纯旋转射流钻孔深度大.影响直旋混合射流钻头破岩效果的结构参数较多,存在最优破岩效果结构参数,可通过不同参数组合调节破岩钻孔特征.需要进一步开展流场结构与破岩机理分析,为径向水平钻孔中射流钻头的设计提供更好的指导.

  5. 自进式多孔水射流钻头钻孔规律的试验研究%Experimental Study on Drilling Laws by Self-advancing and Multi-hole Jet Bit

    祝效华; 吴丹; 杨兆中


    Because of high cost of technology in the existing sidetrack-drilling horizontal well,long working cycles and poor e-conomic problems,this paper designed a self-advancing and high-pressure water jet bit,which can break the rocks mainly with high-pressure water,and study on bits in the submerged-condition experiment.Meanwhile,the different working pressure,the number of turbine blades and working time are researched,which affects the drilling ability of self-advancing and high-pressure water jet bit.In the end,the best structure parameters of bits are obtained in the process.The experimental results showed that compared with the ordinary jet bit,self-advancing and high-pressure water jet bit can drill deeper,bigger,more regular,and has higher stability at work.In the meantime,In some scope,the greater the working pressure of the jet is,the better the bit drills;as the number of turbine blades increases,the drilling diameter decreases linearly,and the drilling depth increases approximately like quadratic curve.Taking into the difficulty of blade manufacturing,the most appropriate number of blades is 4.The research provides the scientific basis for the selection of jet bit in the horizontal radial wells,which has important engineering significance in increasing drilling efficiency and cutting down the cost.%针对现有侧钻水平井技术成本高,工作周期长和经济性差等难题,该文设计了一种采用高压水力射流为破岩主要动力的自进式高压水射流钻头,并对钻头进行了淹没条件下的试验研究,系统分析了在不同射流工作压力、涡轮叶片数目、射流作用时间等条件下自进式高压射流钻头的钻孔特性,给出了射流钻头最适宜钻孔的结构参数.试验结果表明:自进式高压射流钻头与普通射流钻头相比,具有钻孔深,孔径大而规则,工作时稳定性高等优点.同时,在一定范围内,射流工作压力越大,钻孔效果越好;随着涡轮元件叶片数目的增

  6. 基于BP神经网络的金刚石涂层钻头失效在线检测%Based on BP Neural Network of Diamond Coating Drill Failure On-line Detection

    彭广盼; 傅蔡安


    In order to find the on-line detection methods of diamond coated drill failure in the drilling process, it studied the form of diamond coated drill failure; Then research the drilling torque characteristics when the drill failure occurs. Based on the torque characteristics, we selected five parameters as neural network input, such as torque slope. We use Kistler 9277 A5 force dynamometer to detect the torque during the drilling process, with the BP neural network calculations and get the drilling drill failure model. The verification results show that the BP neural network-based detection method can effectively detect the diamond coated drill failure in the process of drilling.%为了找到金刚石涂层钻头在钻削过程中钻头失效的在线检测方法,本文对钻头失效的形式进行了分析,然后对钻头失效发生时钻削扭矩的特性进行了研究.采用Kistler 9277A5测力机来检测钻削过程的扭矩值;在分析了扭矩特性的基础上,选取扭矩斜率等5个参数作为神经网络的输入;然后通过BP神经网络的建模,得出钻削过程中钻头的失效模型.验证结果表明,本文提出的基于BP神经网络的检测方法可以有效的检测金刚石涂层钻头钻削加工过程中的失效情况.

  7. 桥古1井快速钻进PDC钻头优化设计与效果分析%Design Optimization and Effect Analysis of Fast Drilling PDC Bit for Well QG-1



    为了提高桥古1井山前构造地层中的钻进速度,对拟用于该井的PDC钻头进行了优化设计.在详细分析该井的地层特点以及邻近区块相似层位井段钻头使用资料的基础上,提出了针对性的优化方案,采用了力平衡布齿设计、等切削轮廓、CFD优化水力结构等现代PDC钻头设计技术,对常规PDC钻头在山前构造中易磨损、易泥包、机械钻速慢等缺陷进行了设计改进.所设计的钻头在桥古1井共使用了2只,使用井段为2 075.12~4 959.00 m,总进尺2 883.88 m,纯钻时间519.2 h,平均钻速5.55 m/h,比设计预期的3.50 m/h提高了58.57%,比预计的工期缩短了30 d.桥古1井的钻井实践表明,提出的钻头选型和优化设计方案可行,同时为山前构造地层优快钻井积累了宝贵经验.%In order to improve the drilling speed of Well QG~1 in the piedmont structural formation, the design of PDC bits was optimized. Based on careful analysis of the formation characteristics and bit data of similar layers in adjacent blocks, pertinent optimization scheme was put forward, which used modern PDC bit design methods such as force balance of cutters arrangement design,equal cutting profile,and CFD optimization of hydraulic structure,Defects of conventional PDC bit in piedmont structure such as easy abrasion, easy balling,slow drilling speed were modified. Two such designed bits altogether were used in Well QG-1 ,to drill from 2 075. 12 m to 4 959. 00 m. With a total footage of 2 883. 88 m,the net drilling time of 519. 2 h,the average drilling speed was 5. 55 m/h, which is 58. 57% faster than the expected design of 3. 50 m/h, resulting in a reduction of drilling time of 30 d. Drilling in Well QG~1 showed the methods of bit selection and design optimization were feasible,at the same time precious experience for piedmont formation drilling was accumulated.

  8. Introduction to drilling technology

    Mellor, Malcom


    Terrestrial drilling technology is reviewed. The general requirements for a drilling system are given and conventional drilling techniques (rotary drag-bit, rotary roller-bit, percussive, rotary percussive) are described. Unconventional techniques for penetrating solids are outlined, including thermal drilling (spalling or melting), projectile penetration, high pressure liquid jets, explosive jets, erosion by projectile streams, and chemical penetration. Special attention is given to drilling in ice and frozen soils, performance data are given, including values for penetration rate and specific energy consumption. The principles, theory and equipment relating to each drilling technique are indicated by means of diagrams.

  9. New measuring techniques in the drill bit for recording of the full-face cutting rate and consolidation of the roadway sides in the drill bit area; Neue Messverfahren im Bohrkopf zur Erfassung des Vollschnittmaschinenvortriebs und Konsolidierung der Streckenstoesse im Bohrkopfbereich

    Kuehnemann, D.


    The safety of full-face cutting machines has to be assured also in greater depths. In addition, one wants to attain information about the rock conditions as early as possible in the case of occurring faults. For this reason, new systems were to be developed for monitoring of full-face cutting machines. Numerous measuring systems and monitoring systems were used and examined within the framework of the project works. It soon turned out that new systems had to be developed and tested for precise monitoring. Flexible microprocessor systems, sensors and actuators were developed and tested for the respective specific case of application. After several years of development work a new system was developed, which is continuous and transparently from the drill bit area to the surface area. Excavations in the drill bit area are recognized already immediately behind the drift face. Position and quantity of the excavations are transmitted and processed to a central microprocessor by underground ultrasonic sensors. With the aid of specific technologies and newly developed building materials, these excavations are already consolidated and/or saved in the drill bit in front of the dust shield. The cutting rolls are monitored above ground, and the position of the full-face cutting machine is specified above ground. The automatic control via a laser sensor system is also carried out from above ground. In addition to control and monitoring, all other relevant parameters are transmitted from the underground machine to the surface, where they are indicated and recorded. With the technical data which are available in the computer, the data required for optimal heading are determined and transmitted to the control elements of the microprocessors. (orig./HS). [Deutsch] Um die Sicherheit bei Vollschnittmaschinen mit dem Vordringen in groessere Teufen zu gewaehrleisten und um moeglichst fruehe Kenntnisse der vorhandenen Gebirgsverhaeltnisse bei auftretenden Stoerungen zu erlangen waren

  10. 空气反循环钻头井底流场分析及结构优化%Analysis on the Bottomhole Flow Field and Structural Optimization of Air Reverse Circulation Drill Bit

    甘心; 殷琨; 殷其雷; 李鹏


    In order to improve the application effect of the reverse circulation air hammer drilling technique,on the construction of rock-socketed pile by using software Fluent,the authors analyzed the horizontal inclination angleθd of flushing nozzles and horizontal inclination angleθk of pressure-restoring grooves on the reverse circulation drill bit used in the construction of rock-socketed pile.The effects of theθd of flushing nozzles and theθk of pressure-restoring grooves on the suction coefficient ω of reverse circulation drill bit are obtained.Meanwhile,aiming at the deficiency in the structure design of central hollow-through hole on the reverse circulation drill bit,we optimized the structure of reverse circulation drill bit;and thereby,the suction capacity is obviously enhanced.A 660 mm reverse circulation drill bit adopted to the optimized structure is processed,and the field tests are carried out.It can be concluded from the test results that the effect of reverse circulation formation is good,the average penetration rate is 6.00 m/h, the surface of weakly weathered rocks is successfully drilled out. This meets the requirements on drilling out the surface of weakly weathered rocks and stability of borehole wall without borehole collapse.%为改善空气潜孔锤反循环钻进技术在大口径嵌岩桩施工中的应用效果,运用 Fluent 软件对嵌岩桩施工用反循环钻头底喷孔水平倾角θd 和扩压槽水平倾角θk 做了进一步的分析和研究,得到θd 和θk 对反循环钻头抽吸系数ω的影响规律。在分析中发现原有反循环钻头中心贯通孔结构设计中的不足之处,并进行了优化,优化后的反循环钻头抽吸效果明显增强。采用优化后的结构加工了一个直径为660 mm 的反循环钻头,并进行现场钻进试验,试验效果良好,平均钻进效率为6.00 m/h,成功嵌入微风化岩层表面,能够满足嵌岩桩施工对嵌入微风化岩层和孔壁稳定、无塌孔的要求。

  11. Effect of copper matrix solder system on the lifespan of diamond drill%Cu基钎料钎焊金刚石套料钻的试验研究

    郭兆翠; 陈燕; 吴杰


    Brazed Ti-coated diamond core drills were experimentally prepared using( Cu80Sn20 )90Ti10, ( Cu90 Sn10) 82Ti18 and (Cu90Sn10)80Ti20 as solder system. These diamond core drills were tested by drilling granite. The effect of the solder systems on the lifespan of diamond drills were detected by three dimension video microscopy and scanning electron microscopy. The results showed that the three kinds of alloy have all realized a firm brazing with diamonds; the diamond drill made with ( Cu80 Sn20 ) 90 Ti10 solder system had the longest working life.%采用真空钎焊工艺,分别以不同成分的Cu基钎料(Cu80 Sn20)90 Ti10、( Cu90 Sn10)82 Ti18以及(Cu90Sn10) 80Ti20制备了镀钛金刚石套料钻,并进行了花岗岩钻削试验.采用三维视频显微镜、扫描电镜观察了各种钎料钎焊金刚石套料钻的磨损情况.结果表明:3种配比的钎料对金刚石均已实现牢固结合;(Cu80Sn20)90Ti10合金较(Cu90Sn10) 82Ti18合金和(Cu90 Sn10) 80Ti20合金钎焊金刚石套料钻有更长的使用寿命.

  12. Drilling optimization methodology - 25 de Mayo El Medanito - Neuquen - Argentina

    Aguero, Guillermo [Smith International, Inc., Houston, TX (United States); Lugones, Juan M. [PETROBRAS Argentina S.A. (Argentina); Marzialetti, Humberto [Pride San Antonio (Argentina)


    This paper was prepared based on the optimization of the performance and wear pattern of Polycrystalline Diamond Cutter (PDC) bits used in 25 de Mayo S.E. El Medanito Field, Neuquen/Argentina out of a joint effort done by the operator and the service company. The main objective was to reach the casing point in a single bit run at a reasonable penetration rate of the 8 1/2'' section (Choiyoi Formation - Igneous Rock), in order to avoid the use of an extra tungsten carbide insert roller cone bit to reach (4400 ft) which increases the drilling costs as well as allows to a higher exposure to accidents during trips in and out of the hole. A methodology was introduced to the field operations enabling a close follow-up to optimize the drill bit cutting structures, operating conditions, as well as the incorporation of state-of-the-art technology regarding cutters and its geometry. This proved less wear on cutting structures of PDC bits, leading to the achievement of the established casing set depth with reduction of drilling hours and being cost effective to the Operator. (author)

  13. Application program of CRUST-1 10km continental scientific drilling rig in SK-2 scientific drilling well

    Sun, Youhong; Gao, Ke; Yu, Ping; Liu, Baochang; Guo, Wei; Ma, Yinlong; Yang, Yang


    treatment and high temperature resistant cementing materials, and bionic bits,that is coupling bionic PDC tooth bit and diamond-impregnated bit for hard rock.All parts of CRUST-1 were successfully assembled along with the derrick and base lift and transported about 3456 kilometers from manufacture,GuangHan city in southwest China's Sichuan province,to the well site of SK-2 in end of 2013.SK-2 will be finished during next 4 years.


    Nediljka Gaurina-Međimurec


    Full Text Available Casing drilling is an alternative option to conventional drilling and uses standard oilfield casing instead of drillstring. This technology is one of the greatest developments in drilling operations. Casing drilling involves drilling and casing a well simultaneously. In casing driling process, downhole tools can be retrieved, through the casing on wire-line, meaning tool recovery or replacement of tools can take minutes versus hours under conventional methods. This process employs wireline-retrievable tools and a drill-lock assembly, permitting bit and BHA changes, coring, electrical logging and even directional or horizontal drilling. Once the casing point is reached, the casing is cemented in place without tripping pipe.

  15. Study on diamond bit matrix materials made of tungsten carbide and steel shot%金刚石钻头胎体材料碳化钨一铸钢丸的试验研究

    刘志义; 彭金龙; 段隆臣


    本文介绍了一种新的金刚石钻头胎体材料碳化钨-铸钢丸,这种钻头体材料的特点是钻头体表面使用铸造碳化钨材料,心部使用铸钢丸材料,从而实现钻头体表面耐磨抗冲蚀,心部高强高韧的特点.测试了这种钻头体心部材料的力学性能和表层材料的耐磨抗冲蚀能力,同时还介绍了使用含胶碳化钨粉涂抹在钻头模具表面和石墨替棒表面的方法.由于钻头体心部力学性能的提高,和传统的铸造碳化钨粉胎体金刚石钻头相比,这种方法制备的钻头体可以设计更宽更深的钻头体排屑槽,从而有利于提高钻头的钻进性能.%A new kind of diamond bit matrix material made of tungsten carbide and steel shots was introduced. The characteristics of this material are as follows: The outer bit body is of cast tungsten-carbide and the inside material is of cast steel shot, so the bit body has high wear resistance and good mechanical properties at the same time. The mechanical properties inside and the wear resistance outside of the bit were tested. At the same time a method was introduced, that is to apply a mixture of glue-included tungsten-carbide powder on the surface of the bit mold and graphite stick. The improved mechanical properties inside and good wear resistance outside made it possible to design wider and deeper junk slots. Thus the performance of bit was improved hopefully.

  16. Deep Drilling Basic Research: Volume 4 - System Description. Final Report, November 1988--August 1990

    Anderson, E.E.; Maurer, W.C.; Hood, M.; Cooper, G.; Cook, N.


    The first section of this Volume will discuss the ''Conventional Drilling System''. Today's complex arrangement of numerous interacting systems has slowly evolved from the very simple cable tool rigs used in the late 1800s. Improvements to the conventional drilling rig have varied in size and impact over the years, but the majority of them have been evolutionary modifications. Each individual change or improvement of this type does not have significant impact on drilling efficiency and economics. However, the change is almost certain to succeed, and over time--as the number of evolutionary changes to the system begin to add up--improvements in efficiency and economics can be seen. Some modifications, defined and described in this Volume as Advanced Modifications, have more than just an evolutionary effect on the conventional drilling system. Although the distinction is subtle, there are several examples of incorporated advancements that have had significantly more impact on drilling procedures than would a truly evolutionary improvement. An example of an advanced modification occurred in the late 1970s with the introduction of Polycrystalline Diamond Compact (PDC) drill bits. PDC bits resulted in a fundamental advancement in drilling procedures that could not have been accomplished by an evolutionary improvement in materials metallurgy, for example. The last drilling techniques discussed in this Volume are the ''Novel Drilling Systems''. The extent to which some of these systems have been developed varies from actually being tested in the field, to being no more than a theoretical concept. However, they all have one thing in common--their methods of rock destruction are fundamentally different from conventional drilling techniques. When a novel drilling system is introduced, it is a revolutionary modification of accepted drilling procedures and will completely replace current techniques. The most prominent example of a

  17. Jianghan PDC Bits Open Good Market in Singapore

    Wang Tongliang


    @@ The PDC bits produced by PDC Division,Jianghan Drill Bit Plant won good reputation,because of its good quality and appearance in 94 South-east Asia Offshore Petroleum Engineering Product Exhibition held by Singapore International Exhibition Center.

  18. Rotary steerable motor system for underground drilling

    Turner, William E. (Durham, CT); Perry, Carl A. (Middletown, CT); Wassell, Mark E. (Kingwood, TX); Barbely, Jason R. (Middletown, CT); Burgess, Daniel E. (Middletown, CT); Cobern, Martin E. (Cheshire, CT)


    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  19. Rotary steerable motor system for underground drilling

    Turner, William E.; Perry, Carl A.; Wassell, Mark E.; Barbely, Jason R.; Burgess, Daniel E.; Cobern, Martin E.


    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  20. Rotary steerable motor system for underground drilling

    Turner, William E.; Perry, Carl A.; Wassell, Mark E.; Barbely, Jason R.; Burgess, Daniel E.; Cobern, Martin E.


    A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

  1. Modeling pellet impact drilling process

    Kovalev, Artem Vladimirovich; Ryabchikov, Sergey Yakovlevich; Isaev, Evgeniy Dmitrievich; Ulyanova, Oksana Sergeevna


    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling t...

  2. 基于Excel的孕镶金刚石钻头胎体配料计算%Material proportioning calculation of the impregnated diamond bit carcase based on Excel

    刘全心; 刘青; 柯文斌


    Principles of raw material selection when producing diamond bits are briefly introduced.Calculation formulae and progress by Excel,as well as basic principles,calculating program and formulae of each ingredient are listed.Results show that this program has advantages of fast calculation,easy handling and printing.The program is good for the improvement and management of the production data.%介绍了孕镶金刚石钻头在设计制造过程中配料计算的原料选择原则,给出了Excel实现配料计算的计算原理,及各项组分的计算程序、计算公式和Excel单元格计算公式实现.对计算结果的比较分析表明:该程序计算结果准确、操作简便,能快速显示计算结果并直接打印,有利于钻头生产的配料改进和数据的科学管理.

  3. Percussive Augmenter of Rotary Drills for Operating as a Rotary-Hammer Drill

    Aldrich, Jack Barron (Inventor); Bar-Cohen, Yoseph (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bao, Xiaoqi (Inventor); Scott, James Samson (Inventor)


    A percussive augmenter bit includes a connection shaft for mounting the bit onto a rotary drill. In a first modality, an actuator percussively drives the bit, and an electric slip-ring provides power to the actuator while being rotated by the drill. Hammering action from the actuator and rotation from the drill are applied directly to material being drilled. In a second modality, a percussive augmenter includes an actuator that operates as a hammering mechanism that drives a free mass into the bit creating stress pulses that fracture material that is in contact with the bit.

  4. An Easy-To-Use Method for Tracking Rock-Bit Wear While Drilling Une méthode pratique pour suivre l'usure des outils au cours du forage

    Fay H.


    Full Text Available One key factor in minimizing drilling costs is knowledge of rock-bit behaviour at the bottom of the well and particularly the state of bit wear. This paper describes a method giving information about bittooth wear while drilling. The basic concept requires the following torque equation that is a function of weight-on-bit (W,TOB = uW + vW²This equation is determined from measurement-while-drilling data, and knowledge of v provides the bit wear state, given the close correlation between these two parameters. Therefore a chief difficulty in the question is to find such a correlation. The theoretical approach, many laboratory drilling tests, and some fields results are described. Laboratory tests and field results have quantitatively confirmed the validity of the concept. It was found that v decreases as a quasi-linear function of bit wear and accordingly may be considered as a real-time wear criterion. Moreover the value of v is moderately affected by formation type. In the harsh economic environment of today, field applications of the method should lead to more accurate decisions as to when to pull out bits and thus to a reduction of drilling costs. Depuis 1985 l'Institut Français du Pétrole, avec la participation de Total CFP et de la Société Nationale Elf Aquitaine, a entrepris des travaux afin d'établir une méthode d'évaluation, en cours de forage, du degré d'usure des outils à dents fraisées. Cette évaluation permet en effet d'augmenter la sécurité et de réduire le coût d'un forage, en évitant par exemple la remontée précoce d'un outil peu usé ou la perte d'un outil au fond. Le procédé étudié se différencie de la plupart des méthodes classiques, du fait d'une estimation effective de l'usure en temps réel à partir de mesures de fond (1. Celles-ci correspondent au poids (W et au couple (T sur l'outil. La méthode est fondée sur la relation suivante, liant le couple au poids : T = uW + vW² Pour un outil neuf la

  5. Thermal numerical assessment of jawbone drilling factor during implantology

    Adel Pirjamali Neisiani


    Full Text Available Background and Aims: Optimization drilling parameters in order to temperature decrease during creation of hole in the bone is an interested issue. The aim of this study was to achieve optimum values of drilling parameters based on the creation of minimum temperature during jawbone drilling. Materials and Methods: In this study two models of mandible and maxilla was created and teeth 2, 5 and 8 from maxilla and teeth 25, 28 and 31 from mandible were removed. The drilling operation was performed under different conditions on jawbone models using finite element analysis and the maximum temperatures were measured in adjacent of holes. Results: Drill bit head angle of 70 degrees was created the lowest maximum temperature during drilling operation. The lowest maximum temperatures were observed in the drill bit rotational speed, drill bit feed rate and the force exerted on the drill bit equal to 200 rpm, 120 mm/min and 60 N, respectively. The use of irrigation can decrease the maximum bone temperature about 7ºC. The maximum temperature differences in various regions of mandible and maxilla were approximately about 1ºC. Conclusion: Sharpness of drill bit head angle, reduction of drill bit rotational speed, increasing drill bit feed rate and exerted force on drill bit and also the use of irrigation played effective roles in temperature decrease during jawbone drilling. Drilling site did not have important effect on the temperature changes during jawbone drilling.

  6. Drilling Optimization: A Review

    Abhilash M Bharadwaj


    Full Text Available With rapidly growing global demand for energy resources, oil and gas exploration & production companies face mounting pressure to maximize supply and increase the rate of discovery for new energy sources. Increasingly operating in more remote locations and investing heavily in equipment and facilities, companies face greater financial and operational risks than ever before. Optimization of drilling parameters during drilling operations aims to optimize weight on bit, bit rotation speed for obtaining maximum drilling rate as well as minimizing the drilling cost. Communication and computer technologies are among the most important disciplines which can contribute to drilling optimization. Large amount of data could be piped through different locations on the planet in reliable and time efficient manners.

  7. Drilling Optimization: A Review

    Vinayaka S


    Full Text Available With rapidly growing global demand for energy resources, oil and gas exploration & production companies face mounting pressure to maximize supply and increase the rate of discovery for new energy sources. Increasingly operating in more remote locations and investing heavily in equipment and facilities, companies face greater financial and operational risks than ever before. Optimization of drilling parameters during drilling operations aims to optimize weight on bit, bit rotation speed for obtaining maximum drilling rate as well as minimizing the drilling cost. Communication and computer technologies are among the most important disciplines which can contribute to drilling optimization. Large amount of data could be piped through different locations on the planet in reliable and time efficient manners.

  8. High temperature brazing of diamond tools

    YAO Zheng-jun; SU Hong-hua; FU Yu-can; XU Hong-jun


    A new brazing technique of diamond was developed. Using this new technique optimum chemical and metallurgical bonding between the diamond grits and the carbon steel can be achieved without any thermal damages to diamond grits. The results of microanalysis and X-ray diffraction analysis reveal that a carbide layer exists between the diamond and the matrix, which consists of Cr3C2, Cr7C3 and Cr23C6. Performance tests show that the brazed diamond core-drill has excellent machining performance. In comparison with traditional electroplated diamond core-drill, the brazed diamond core-drill manufactured using the new developed technique has much higher machining efficiency and much longer operating life.

  9. Drilling Systems for Extraterrestrial Subsurface Exploration

    Zacny, K.; Bar-Cohen, Y.; Brennan, M.; Briggs, G.; Cooper, G.; Davis, K.; Dolgin, B.; Glaser, D.; Glass, B.; Gorevan, S.; Guerrero, J.; McKay, C.; Paulsen, G.; Stanley, S.; Stoker, C.


    Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications.

  10. Industrial diamond

    Olson, D.W.


    An overview of the industrial diamond industry is provided. More than 90 percent of the industrial diamond consumed in the U.S. and the rest of the world is manufactured diamond. Ireland, Japan, Russia, and the U.S. produce 75 percent of the global industrial diamond output. In 2000, the U.S. was the largest market for industrial diamond. Industrial diamond applications, prices for industrial diamonds, imports and exports of industrial diamonds, the National Defense Stockpile of industrial diamonds, and the outlook for the industrial diamond market are discussed.

  11. The Hone Edge of the Carbide Cemented Drill Bit and the Measurement of Hone Edge Radius%硬质合金钻头刃口钝圆及其半径的测量

    王弢; 周一丹; 张平


    指出了硬质合金钻头刃口钝圆对切削加工的影响,说明了硬质合金钻头刃口钝圆的重要性,简要介绍了刃口钝圆的方法及常规的测量方法,提出了在Matlab中用最小二乘法拟合的数据处理方法来获得刀口钝圆半径值.与传统测量方法相比,此方法避免了常规测量方法所产生的人为的不确定因素,减少了由于测量系统的精确度引起的误差,可以准确地判断是否达到钝化参数的要求,对优化刀具结构设计、提高切削性能、增加刀具使用寿命有重要的作用和实际意义.%The influence of hone edge radius of carbide drill bit during cutting was pointed out here, and the importance of hone edge was UlustratedAnd then,the measurement of hone edge and the way to measure were introduced briefly.The hone edge radius were acquired by a new data processing method of the least squares fitting, which can avoid the artificial uncertainties,reduce the errors caused by the accuracy of the measurement system in the conventional measurement methods,and it has an important significance for optimizing cutting tool structure design, improving cutting performance, and increasing tool life.

  12. Stress Analysis and Optimum Design of PDC Die for Offshore Drilling Engineering

    ZHOU Si-zhu; DUAN Meng-lan; Segen ESTEFEN


    The maximum internal tangential stress is a critical parameter for the design of the PDC (polycrystalline diamond compact) die that has been widely applied to offshore oil drilling. A simple equation for the calculation of the stress is proposed, and verified by the test data from Kingdream Corp. of China, the largest bit Company in China. An optimum method for the design of the PDC die is presented and demonstrated in detail, and software for the design and FEM analysis of the die is developed on the basis of the method. This software has been used in oil industry in recent years.

  13. Ultra-fast calculations using diamond

    Van Dijk, T.


    TU Delft researchers have managed to use a piece of diamond to hold four quantum bits that can be spun, flipped and entangled with each other. This is an important step towards a working quantum computer

  14. Modeling and experimentation of bone drilling forces.

    Lee, JuEun; Gozen, B Arda; Ozdoganlar, O Burak


    Prediction and control of bone drilling forces are critical to the success of many orthopaedic operations. Uncontrolled and large forces can cause drill-bit breakage, drill breakthrough, excessive heat generation, and mechanical damage to the bone. This paper presents a mechanistic model for prediction of thrust forces and torques experienced during bone drilling. The model incorporates the radially varying drill-bit geometry and cutting conditions analytically, while capturing the material and friction properties empirically through a specific energy formulation. The forces from the chisel edge are modeled by considering the indentation process that occurs in the vicinity of the drill-bit axis. A procedure is outlined to calibrate the specific energies, where only a small number of calibration experiments are required for a wide range of drilling conditions and drill-bit geometry. The calibration parameters for the cortical portions of bovine tibia are identified through drilling tests. Subsequently, a series of validation tests are conducted under different feed rates and spindle speeds. The thrust forces and torques were observed to vary considerably between bones from different animals. The forces from the model were seen to match well with those from the experimentation within the inherent variations from the bone characteristics. The model can be used to select favorable drilling conditions, to assist in robotic surgeries, and to design optimal orthopaedic drill bits. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Reducing temperature elevation of robotic bone drilling.

    Feldmann, Arne; Wandel, Jasmin; Zysset, Philippe


    This research work aims at reducing temperature elevation of bone drilling. An extensive experimental study was conducted which focused on the investigation of three main measures to reduce the temperature elevation as used in industry: irrigation, interval drilling and drill bit designs. Different external irrigation rates (0 ml/min, 15 ml/min, 30 ml/min), continuously drilled interval lengths (2 mm, 1 mm, 0.5 mm) as well as two drill bit designs were tested. A custom single flute drill bit was designed with a higher rake angle and smaller chisel edge to generate less heat compared to a standard surgical drill bit. A new experimental setup was developed to measure drilling forces and torques as well as the 2D temperature field at any depth using a high resolution thermal camera. The results show that external irrigation is a main factor to reduce temperature elevation due not primarily to its effect on cooling but rather due to the prevention of drill bit clogging. During drilling, the build up of bone material in the drill bit flutes result in excessive temperatures due to an increase in thrust forces and torques. Drilling in intervals allows the removal of bone chips and cleaning of flutes when the drill bit is extracted as well as cooling of the bone in-between intervals which limits the accumulation of heat. However, reducing the length of the drilled interval was found only to be beneficial for temperature reduction using the newly designed drill bit due to the improved cutting geometry. To evaluate possible tissue damage caused by the generated heat increase, cumulative equivalent minutes (CEM43) were calculated and it was found that the combination of small interval length (0.5 mm), high irrigation rate (30 ml/min) and the newly designed drill bit was the only parameter combination which allowed drilling below the time-thermal threshold for tissue damage. In conclusion, an optimized drilling method has been found which might also enable drilling in more

  16. Estimating Hardness from the USDC Tool-Bit Temperature Rise

    Bar-Cohen, Yoseph; Sherrit, Stewart


    A method of real-time quantification of the hardness of a rock or similar material involves measurement of the temperature, as a function of time, of the tool bit of an ultrasonic/sonic drill corer (USDC) that is being used to drill into the material. The method is based on the idea that, other things being about equal, the rate of rise of temperature and the maximum temperature reached during drilling increase with the hardness of the drilled material. In this method, the temperature is measured by means of a thermocouple embedded in the USDC tool bit near the drilling tip. The hardness of the drilled material can then be determined through correlation of the temperature-rise-versus-time data with time-dependent temperature rises determined in finite-element simulations of, and/or experiments on, drilling at various known rates of advance or known power levels through materials of known hardness. The figure presents an example of empirical temperature-versus-time data for a particular 3.6-mm USDC bit, driven at an average power somewhat below 40 W, drilling through materials of various hardness levels. The temperature readings from within a USDC tool bit can also be used for purposes other than estimating the hardness of the drilled material. For example, they can be especially useful as feedback to control the driving power to prevent thermal damage to the drilled material, the drill bit, or both. In the case of drilling through ice, the temperature readings could be used as a guide to maintaining sufficient drive power to prevent jamming of the drill by preventing refreezing of melted ice in contact with the drill.

  17. Testing methodology of diamond composite inserts to be used in the drilling of petroleum wells; Metodologia de testes de insertos compositos diamantados a serem usados na perfuracao de pocos de petroleo

    Bobrovnitchii, G.S.; Filgueira, M.; Skury, A.L.D.; Tardim, R.C. [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacazes, RJ (Brazil)], e-mail:


    The useful life of the inserts used in the cutters of the drills for perforation of oil wells determines the quality of the perforation as well as the productivity. Therefore, the research of the wear of insert is carried through with the objective to foretell the most important properties of the inserts. Due to the fact of the UENF to be developing the processes of composites sintering to the synthetic diamond base, it is interesting to define the testing methodology of the gotten inserts. The proposed methodology is based on the evaluation of the wear suffered by de sample. For this end a micro processed 'Abrasimeter', model AB800-E, manufactured for the Contenco Company was used. The instrument capacity is 1,36 kVA; axial load applied in the cutter up to 50 kgf; rotation of table speed 20 rpm; course of the tool in radial direction speed before 2 m/min; dimensions of the granite block D = 808 mm, d = 484 mm, h = 50 mm. The gotten results show that the proposed methodology can be used for the evaluation of the inserts of the cutters applied in perforation drills. (author)

  18. FY 79 Lava Lake Drilling Program: results of drilling experiments

    Neel, R.R.; Striker, R.P.; Curlee, R.M.


    A drilling program was conducted in December 1978 and January and February 1979 to continue the characterization of the solid and liquid rock components of the Kilauea Iki lava lake. Six holes were drilled from the surface and two previously drilled holes were reentered and deepened for the purposes of measuring downhole temperature profiles, recovering samples of solid, plastic, and molten rock, measuring crust permeability, and determining the performance of conventional and special drilling techniques. Conventional HQ-size (3.78 inches diameter) core drilling equipment using water for cooling and cuttings removal was used to successfully drill during initial entry into 1052/sup 0/C formations. Conventional drilling in reentering flow-back rock was less reliable. The specially designed water jet-augmented drag bit or water jet-augmented core bit was needed to drill reliably into the plastic flow-back rock and through liquid rock veins. This document contains the drill performance data which were recorded during drilling in the crust and the plastic and molten rock zones using both conventional and special drilling procedures and equipment.

  19. Influence of electroplating nickel on graphite surface on properties of diamond bit matrix%石墨表面镀镍对金刚石钻头胎体性能的影响

    谢兰兰; 潘秉锁; 段隆臣


    为了解石墨表面镀镍对金刚石钻头胎体性能的影响,采用热压烧结法制备了镀镍石墨/胎体复合材料,用扫描电镜观察石墨镀镍前后与胎体之间界面结合状态的变化,并研究了石墨表面镀镍对复合材料的抗弯强度、洛氏硬度以及在无冷却液的条件下与花岗岩对磨时的摩擦系数和磨损量的影响。结果表明:石墨表面镀镍之后,石墨与胎体之间的结合强度大幅度提高;提高了复合材料的整体性能,以及抗弯强度和硬度;增大了摩擦副的摩擦系数,且增大了胎体的磨损量。石墨表面镀镍提高了石墨/胎体复合材料的物理力学性能,但是降低了其干摩擦性能。%To find out the influence of electroplating nickel on the graphite surface on the properties of diamond bit matrix,the Ni-coated graphite / matrix composite material is prepared by the hot-press method.Then,the change of the interface between the graphite and the matrix is observed by the scanning electron microscope before and after electroplating nickel on the graphite.And the influence of electroplating nickel on the graphite surface on the bending strength and Rockwell hardness of the composite materials are studied.Besides,the influence of electroplating nickel on the graphite surface on the friction coefficient and friction loss of the composite materials while rubbing against granite without coolant is studied.The results show that after electroplating nickel on the graphite,the bending strength between the graphite and the matrix is improved greatly,and the whole performance of the composite materials also improved.As a result,the bending strength and the Rockwell hardness of the composite materials are improved,but the friction coefficient of the friction pair and the friction loss of the composite materials are improved.These show that to electroplate nickel on graphite improves the physical and mechanical properties of the Ni

  20. 金刚石涂层硬质合金阶梯刀具的制备及钻削特性%Preparation and Drilling Characteristics of Diamond Coated Cemented Carbide Step Cutting Tool

    向道辉; 张磊; 张玉龙; 马国峰; 周直昆; 秦强


    The diamond coating was prepared on the surface of the cemented carbide step cutting tool by using double-layered hot filament assisted chemical vapor deposition (CVD).Then the drilling characteristics and wear properties of the uncoated and coated cutting tools during drilling the composite fiber brake pad,as well as the surface qualities of the machined hole,were compared and analyzed.The results show that under the high speed drilling condition,the axial force and torque of coated cutting tool were obviously lower than those of uncoated cutting tool,showing a better drilling performance.After drilling 10 holes at the same speed and feed rate,the flank wear height of the coated cutting tool was about 0.025 mm,which was much less than the wear standard (0.2 mm), while that (0.15 mm)of uncoated cutting tool was close to the wear standard,indicating that the wear resistant of the coated cutting tool was better than that of uncoated cutting tool.The hole boundary drilled by the coated cutting tool was smooth and had no burr and tearing.The surface quality was better than that drilled by uncoated cutting tool.%采用双层热丝化学气相沉积(CVD)法在硬质合金阶梯刀具表面制备了金刚石涂层,对比分析了无涂层和涂层刀具钻削复合纤维刹车片的钻削特性和磨损性能以及加工孔的表面质量.结果表明:在高速钻削条件下,涂层刀具的轴向力和扭矩明显小于无涂层刀具的,表现出更好的钻削性能;当以相同的转速和进给量钻削出10个孔后,涂层刀具的后刀面磨损高度约为0.025 mm,远小于磨损标准(0.2 mm),无涂层刀具的后刀面磨损高度(0.15 mm)则接近磨损标准,涂层刀具的耐磨性能优于无涂层刀具的;涂层刀具钻削孔的四周圆滑,没有毛刺及撕裂现象,其表面质量好于无涂层刀具钻削孔的.

  1. 涂层钻头钻削碳纤维复合材料的轴向力研究%Study of drilling thrust force of coated drills in drilling the carbon fiber reinforced plastic

    魏良耀; 程寓


    不同刀具材料对碳纤维复合材料的加工有较大的影响.通过合理选择钻头的基体材料和涂层材料,基于正交试验综合分析不同涂层材料、主轴转速及进给速度对钻削轴向力的影响.试验结果表明,涂层材料对轴向力的影响最大,涂层钻头的钻削轴向力比无涂层YG6X钻头小很多,类金刚石涂层(DLC)钻头最小.TiAIN和TiCN涂层钻头都有不同程度的磨损,DLC钻头的耐磨性和加工质量都远远高于其他涂层.%Different tool materials have a greater impact on the processing of carbon fiber reinforced plastic. Through the reasonable choice of substrate material and coating materials of the drill, based on the orthogonal experiment and comprehensive analysis of the coating materials, different spindle speeds and feed drilling speeds on the effect of the thrust force. The results show that coating material is the biggest influencing factor for drilling thrust force, compared to the uncoated drill bits, the thrust force of the coating drill is much smaller, and the least is DLC drill. TiAIN and TiCN coating drill both have different degrees of wear. The wear resistance and processing quality of the diamond-like-coating ( DLC) drill are far higher than other coatings.

  2. Steerable percussion air drilling system

    Bui, H.D.; Meyers, J.A.; Yost, A.B. II


    By increasing penetration rates and bit life, especially in hard formations, the use of down-hole air hammers in the oil field has significantly reduced drilling costs in the Northeast US and West Texas. Unfortunately, drilling by this percussion method has been limited mostly to straight hole applications. This paper presents a new concept of a percussion drilling tool which performs both the function of a down-hole hammer as well as that of a down-hole motor. Such a drilling tool, being introduced here as Steerable Percussion Air Drilling System (SPADS), eliminates the necessity to rotate the drill string and, consequently, enables the use of down-hole air hammers to drill directional wells.

  3. Buckling and dynamic analysis of drill strings for core sampling

    Ziada, H.H., Westinghouse Hanford


    This supporting document presents buckling and dynamic stability analyses of the drill strings used for core sampling. The results of the drill string analyses provide limiting operating axial loads and rotational speeds to prevent drill string failure, instability and drill bit overheating during core sampling. The recommended loads and speeds provide controls necessary for Tank Waste Remediation System (TWRS) programmatic field operations.

  4. A Brief Discussion on the Shortcoming Analysis of Drilling Bit Sharpening and Its Skill in Teaching%浅谈教学中钻头的刃磨缺陷分析与技巧


    Drilling is one of the important contents in the field of mechanical processing technology, also is the most widely used one in the machine work. In metal cutting, drilling consumed about one third of the amount. In the actual processing, drill grinding quality directly related to the quality and efficiency of the drilling.%  钻孔加工在机械加工领域中是一项重要的技术,也是当今机械加工中应用最广的一个技术工种。在金属切削加工中,孔加工的工作量约占据了三分之一的量。在实际加工时,钻头的刃磨质量直接关系到钻孔的质量与效率。

  5. High Temperature 300°C Directional Drilling System

    Chatterjee, Kamalesh [Baker Hughes Oilfield Operations, Houston, TX (United States); Aaron, Dick [Baker Hughes Oilfield Operations, Houston, TX (United States); Macpherson, John [Baker Hughes Oilfield Operations, Houston, TX (United States)


    Many countries around the world, including the USA, have untapped geothermal energy potential. Enhanced Geothermal Systems (EGS) technology is needed to economically utilize this resource. Temperatures in some EGS reservoirs can exceed 300°C. To effectively utilize EGS resources, an array of injector and production wells must be accurately placed in the formation fracture network. This requires a high temperature directional drilling system. Most commercial services for directional drilling systems are rated for 175°C while geothermal wells require operation at much higher temperatures. Two U.S. Department of Energy (DOE) Geothermal Technologies Program (GTP) projects have been initiated to develop a 300°C capable directional drilling system, the first developing a drill bit, directional motor, and drilling fluid, and the second adding navigation and telemetry systems. This report is for the first project, “High Temperature 300°C Directional Drilling System, including drill bit, directional motor and drilling fluid, for enhanced geothermal systems,” award number DE-EE0002782. The drilling system consists of a drill bit, a directional motor, and drilling fluid. The DOE deliverables are three prototype drilling systems. We have developed three drilling motors; we have developed four roller-cone and five Kymera® bits; and finally, we have developed a 300°C stable drilling fluid, along with a lubricant additive for the metal-to-metal motor. Metal-to-metal directional motors require coatings to the rotor and stator for wear and corrosion resistance, and this coating research has been a significant part of the project. The drill bits performed well in the drill bit simulator test, and the complete drilling system has been tested drilling granite at Baker Hughes’ Experimental Test Facility in Oklahoma. The metal-to-metal motor was additionally subjected to a flow loop test in Baker Hughes’ Celle Technology Center in Germany, where it ran for more than 100

  6. Acquisition and Retaining Granular Samples via a Rotating Coring Bit

    Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart


    This device takes advantage of the centrifugal forces that are generated when a coring bit is rotated, and a granular sample is entered into the bit while it is spinning, making it adhere to the internal wall of the bit, where it compacts itself into the wall of the bit. The bit can be specially designed to increase the effectiveness of regolith capturing while turning and penetrating the subsurface. The bit teeth can be oriented such that they direct the regolith toward the bit axis during the rotation of the bit. The bit can be designed with an internal flute that directs the regolith upward inside the bit. The use of both the teeth and flute can be implemented in the same bit. The bit can also be designed with an internal spiral into which the various particles wedge. In another implementation, the bit can be designed to collect regolith primarily from a specific depth. For that implementation, the bit can be designed such that when turning one way, the teeth guide the regolith outward of the bit and when turning in the opposite direction, the teeth will guide the regolith inward into the bit internal section. This mechanism can be implemented with or without an internal flute. The device is based on the use of a spinning coring bit (hollow interior) as a means of retaining granular sample, and the acquisition is done by inserting the bit into the subsurface of a regolith, soil, or powder. To demonstrate the concept, a commercial drill and a coring bit were used. The bit was turned and inserted into the soil that was contained in a bucket. While spinning the bit (at speeds of 600 to 700 RPM), the drill was lifted and the soil was retained inside the bit. To prove this point, the drill was turned horizontally, and the acquired soil was still inside the bit. The basic theory behind the process of retaining unconsolidated mass that can be acquired by the centrifugal forces of the bit is determined by noting that in order to stay inside the interior of the bit, the

  7. Modeling and analysis of stick-slip and bit bounce in oil well drillstrings equipped with drag bits

    Kamel, Jasem M.; Yigit, Ahmet S.


    Rotary drilling systems equipped with drag bits or fixed cutter bits (also called PDC), used for drilling deep boreholes for the production and the exploration of oil and natural gas, often suffer from severe vibrations. These vibrations are detrimental to the bit and the drillstring causing different failures of equipment (e.g., twist-off, abrasive wear of tubulars, bit damage), and inefficiencies in the drilling operation (reduction of the rate of penetration (ROP)). Despite extensive research conducted in the last several decades, there is still a need to develop a consistent model that adequately captures all phenomena related to drillstring vibrations such as nonlinear cutting and friction forces at the bit/rock formation interface, drive system characteristics and coupling between various motions. In this work, a physically consistent nonlinear model for the axial and torsional motions of a rotating drillstring equipped with a drag bit is proposed. A more realistic cutting and contact model is used to represent bit/rock formation interaction at the bit. The dynamics of both drive systems for rotary and translational motions of the drillstring, including the hoisting system are also considered. In this model, the rotational and translational motions of the bit are obtained as a result of the overall dynamic behavior rather than prescribed functions or constants. The dynamic behavior predicted by the proposed model qualitatively agree well with field observations and published theoretical results. The effects of various operational parameters on the dynamic behavior are investigated with the objective of achieving a smooth and efficient drilling. The results show that with proper choice of operational parameters, it may be possible to minimize the effects of stick-slip and bit-bounce and increase the ROP. Therefore, it is expected that the results will help reduce the time spent in drilling process and costs incurred due to severe vibrations and consequent

  8. A new thermal model for bone drilling with applications to orthopaedic surgery.

    Lee, JuEun; Rabin, Yoed; Ozdoganlar, O Burak


    This paper presents a new thermal model for bone drilling with applications to orthopaedic surgery. The new model combines a unique heat-balance equation for the system of the drill bit and the chip stream, an ordinary heat diffusion equation for the bone, and heat generation at the drill tip, arising from the cutting process and friction. Modeling of the drill bit-chip stream system assumes an axial temperature distribution and a lumped heat capacity effect in the transverse cross-section. The new model is solved numerically using a tailor-made finite-difference scheme for the drill bit-chip stream system, coupled with a classic finite-difference method for the bone. The theoretical investigation addresses the significance of heat transfer between the drill bit and the bone, heat convection from the drill bit to the surroundings, and the effect of the initial temperature of the drill bit on the developing thermal field. Using the new model, a parametric study on the effects of machining conditions and drill-bit geometries on the resulting temperature field in the bone and the drill bit is presented. Results of this study indicate that: (1) the maximum temperature in the bone decreases with increased chip flow; (2) the transient temperature distribution is strongly influenced by the initial temperature; (3) the continued cooling (irrigation) of the drill bit reduces the maximum temperature even when the tip is distant from the cooled portion of the drill bit; and (4) the maximum temperature increases with increasing spindle speed, increasing feed rate, decreasing drill-bit diameter, increasing point angle, and decreasing helix angle. The model is expected to be useful in determination of optimum drilling conditions and drill-bit geometries.

  9. Industrial diamond

    Olson, D.W.


    Estimated 2012 world production of natural and synthetic industrial diamond was about 4.45 billion carats. During 2012, natural industrial diamonds were produced in at least 20 countries, and synthetic industrial diamond was produced in at least 12 countries. About 99 percent of the combined natural and synthetic global output was produced in Belarus, China, Ireland, Japan, Russia, South Africa and the United States. During 2012, China was the world’s leading producer of synthetic industrial diamond followed by the United States and Russia. In 2012, the two U.S. synthetic producers, one in Pennsylvania and the other in Ohio, had an estimated output of 103 million carats, valued at about $70.6 million. This was an estimated 43.7 million carats of synthetic diamond bort, grit, and dust and powder with a value of $14.5 million combined with an estimated 59.7 million carats of synthetic diamond stone with a value of $56.1 million. Also in 2012, nine U.S. firms manufactured polycrystalline diamond (PCD) from synthetic diamond grit and powder. The United States government does not collect or maintain data for either domestic PCD producers or domestic chemical vapor deposition (CVD) diamond producers for quantity or value of annual production. Current trade and consumption quantity data are not available for PCD or for CVD diamond. For these reasons, PCD and CVD diamond are not included in the industrial diamond quantitative data reported here.

  10. Superhard nanophase cutter materials for rock drilling applications

    Voronov, O.; Tompa, G.; Sadangi, R.; Kear, B.; Wilson, C.; Yan, P.


    The Low Pressure-High Temperature (LPHT) System has been developed for sintering of nanophase cutter and anvil materials. Microstructured and nanostructured cutters were sintered and studied for rock drilling applications. The WC/Co anvils were sintered and used for development of High Pressure-High Temperature (HPHT) Systems. Binderless diamond and superhard nanophase cutter materials were manufactured with help of HPHT Systems. The diamond materials were studied for rock machining and drilling applications. Binderless Polycrystalline Diamonds (BPCD) have high thermal stability and can be used in geothermal drilling of hard rock formations. Nanophase Polycrystalline Diamonds (NPCD) are under study in precision machining of optical lenses. Triphasic Diamond/Carbide/Metal Composites (TDCC) will be commercialized in drilling and machining applications.

  11. Steerable percussion air drilling system

    Bui, H.D.; Gray, M.A.; Oliver, M.S.


    In the Steerable Percussion Air Drilling System (SPADS), air percussion is used to drill directionally in hard formations. Compared to mud or air powered PDM motors, SPADS offers directional drilling at high penetration rate, reduced mud costs, negligible formation damage, and immediate indication of hole productivity. Field tests turned up problems ranging from tool design to operation procedures; remedies were developed. There is an optimum WOB (weight on bit) at which torque is reasonably low. The hammer was tested at three different line pressures (200, 300, 350 psig) at optimum WOB in granite, limestone, and sandstone.

  12. Rapid Access Ice Drill: A New Tool for Exploration of the Deep Antarctic Ice Sheets and Subglacial Geology

    Goodge, J. W.; Severinghaus, J. P.


    The Rapid Access Ice Drill (RAID) will penetrate the Antarctic ice sheets in order to core through deep ice, the glacial bed, and into bedrock below. This new technology will provide a critical first look at the interface between major ice caps and their subglacial geology. Currently in construction, RAID is a mobile drilling system capable of making several long boreholes in a single field season in Antarctica. RAID is interdisciplinary and will allow access to polar paleoclimate records in ice >1 Ma, direct observation at the base of the ice sheets, and recovery of rock cores from the ice-covered East Antarctic craton. RAID uses a diamond rock-coring system as in mineral exploration. Threaded drill-pipe with hardened metal bits will cut through ice using reverse circulation of Estisol for pressure-compensation, maintenance of temperature, and removal of ice cuttings. Near the bottom of the ice sheet, a wireline bottom-hole assembly will enable diamond coring of ice, the glacial bed, and bedrock below. Once complete, boreholes will be kept open with fluid, capped, and made available for future down-hole measurement of thermal gradient, heat flow, ice chronology, and ice deformation. RAID will also sample for extremophile microorganisms. RAID is designed to penetrate up to 3,300 meters of ice and take sample cores in less than 200 hours. This rapid performance will allow completion of a borehole in about 10 days before moving to the next drilling site. RAID is unique because it can provide fast borehole access through thick ice; take short ice cores for paleoclimate study; sample the glacial bed to determine ice-flow conditions; take cores of subglacial bedrock for age dating and crustal history; and create boreholes for use as an observatory in the ice sheets. Together, the rapid drilling capability and mobility of the drilling system, along with ice-penetrating imaging methods, will provide a unique 3D picture of the interior Antarctic ice sheets.

  13. Reliability-Growth of Triplex Drilling Pump

    Hou Yu; ZhaoZhong


    @@ Introduction to triplex pump The triplex pump widely used in oilfields is composed of power end assembly, fluid end assembly, piston-liner spraying system, lubrication system and charging system.The pump delivers mud into oil well. Through nozzles of drilling bit, the mud inside the drilling shaft comes to the annular space between drilling shaft and casing string and then returns to surface.

  14. OMV Yemen's experience in development drilling of the basement reservoir Habban

    Klampfer, Simon [OMV Exploration and Production GmbH, Wien (Austria); Boettcher, Frank [OMV Yemen Exploration and Production (Yemen)


    In 2003 OMV AG took over the activities of PREUSSAG Energie International and became operator of the Yemeni Block S2 (Al Uqlah). Activities concentrated initially an appraising the Khulan reservoir, which was discovered by the Kharwah 1 well. Kharwah 1 was used for long-term testing of a two-meter thick Khulan layer producing a reasonably high and constant oil rate with very little decline. Al Nilam 1 was drilled to prove the economics of the discovery and also to look into the basement. The well was successful and a development plan was submitted to the Yemeni authorities including drilling some 42 wells, constructing field facilities and building an oil exporting pipeline. Up to now some 22 wells have been drilled, encountering a number of technical difficulties. A number of potential performance improvements were examined and tested, i.e. percussion drilling for the top hole section, aerated mud in the second and third section to avoid losses and stabilize the hole and the use of impregnated diamond bits in the basement section. A real breakthrough has not yet been achieved. (orig.)

  15. Geothermal well drilling manual at Cerro Prieto

    Fernandez P., A.; Flores S., M.


    The objective of the drilling manual is to solve all problems directly related to drilling during the construction of a well. In this case, the topics dealt which are drilling fluids and hydraulics to be applied in the field to improve drilling progress, eliminate risks and achieve good well-completion. There are other topics that are applicable such as drill bits and the drilling string, which are closely linked to drilling progress. On this occasion drilling fluid and hydraulics programs are presented, in addition to a computing program for a Casio FX-502P calculator to be applied in the field to optimize hydraulics and in the analysis of hydraulics for development and exploration wells at their different intervals.

  16. 径向水平井自进式旋转射流钻头流场特性分析%Flow Field Study on Self-propelled Conical Jet Bit for Radial Horizontal Drilling

    毕刚; 李根生; 沈忠厚; 黄中伟; 李浩


    为解决径向水平井钻进过程中破岩效率和自进能力的问题,设计了一种自进式旋转射流钻头。运用数值模拟方法,采用RN G k-ε湍流模型对所设计射流钻头的内外流场进行了三维流动特性分析,并分析了射流钻头结构参数对喷嘴流场特性的影响规律,进一步优化了自进式旋转射流钻头。结果表明,自进式旋转射流喷嘴外流场的轴心速度在喷嘴中心线上的速度最大,随着径向半径的增大,轴向速度迅速减小;切向速度沿喷嘴径向呈现出经典的“N”形分布,有利于增大射流破碎岩石的深度和破碎面积;径向速度呈轴对称分布,存在明显的漫流层,有助于岩屑的脱离;自进式旋转射流钻头导向叶轮的螺距和导叶数量,对射流速度有着重要的影响;喷嘴直径对射流流场特性的影响较大。经过优化,得到射流钻头的叶轮螺距16mm,导叶数为2,喷嘴直径为1mm。%A novel self-propelled conical jet bit was designed to settle the problem of rock breaking efficiency and self-propelled ability.The 3D flow characteristics of flow fields inside and outside the designed jet bit were analyzed based on numerical method and RNG k-εturbulent model.Furthermore,the influence of the jet bit structural parameters on flow field characteristics of the jet nozzle was investigated for optimizing the novel jet bit.The experimental results show that the maximum axial velocity of flow field outside the nozzle is on the centerline of the nozzle and the axial velocity rapidly drops with the increase of radial radius.The tangential velocity along the nozzle radial shows classical “N”pattern distribution,which is beneficial for producing larger rock breaking area and depth.The radial velocity exhibits axial-symmetric distribution and has an obvious cross flow layer in favor of cleaning the cuttings.The number of guide vane and the screw pitch of the oriented impeller

  17. Experimental research on characteristics of hole reaming and side cutting of one-cone bits

    Yu Kai'an


    The hole reaming and side cutting characteristics of offset one-cone bit and conventional one-cone bit were investigated on simulated drilling experimental equipment.The borehole diameter was a little larger than the bit diameter due to side force.However,the reaming effect was not very apparent,whether drilling with an offset or conventional one-cone bit.The side cutting displacement increased gradually with increasing depth of drilling and side force.The side cutting displacement of offset one-cone bits was larger than that of conventional ones under the same conditions of weight-on-bit(WOB),rotary speed,side force and borehole depth.

  18. Microgravity Drill and Anchor System

    Parness, Aaron; Frost, Matthew A.; King, Jonathan P.


    This work is a method to drill into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive coring drill, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of drilling is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every drilling application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the drill is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the drill is on a robotic arm, it has the benefit of not reflecting the forces of drilling back to the arm s joints. Combining the drill with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The drilling system s anchor uses hundreds of

  19. Stochastic identification using the maximum likelihood method and a statistical reduction: application to drilling dynamics


    International audience; A drill-string is a slender structure that drills rock to search for oil. The nonlinear interaction between the bit and the rock is of great importance for the drill-string dynamics. The interaction model has uncertainties, which are modeled using the nonparametric probabilistic approach. This paper deals with a procedure to perform the identification of the dispersion parameter of the probabilistic model of uncertainties of a bit-rock interaction model. The bit-rock i...

  20. 烧结金刚石钻头加工Kevlar纤维增强复合材料的试验研究%Experimental Investigation on Drilling Kevlar Fiber Reinforced Composite with Sintered Diamond Bits

    郑雷; 袁军堂; 郭丽



  1. Deep Drilling Basic Research: Volume 5 - System Evaluations. Final Report, November 1988--August 1990



    This project is aimed at decreasing the costs and increasing the efficiency of drilling gas wells in excess of 15,000 feet. This volume presents a summary of an evaluation of various drilling techniques. Drilling solutions were compared quantitatively against typical penetration rates derived from conventional systems. A qualitative analysis measured the impact of a proposed system on the drilling industry. The evaluations determined that the best candidates f o r improving the speed and efficiency of drilling deep gas wells include: PDC/TSD bits, slim-hole drilling, roller-cone bits, downhole motors, top-driven systems, and coiled-tubing drilling.

  2. Counter-Rotating Tandem Motor Drilling System

    Kent Perry


    Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively compared to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger

  3. Phase 1 user instruction manual. A geological formation - drill string dynamic interaction finite element program (GEODYN)

    Tinianow, M.A.; Rotelli, R.L. Jr.; Baird, J.A.


    User instructions for the GEODYN Interactive Finite Element Computer Program are presented. The program is capable of performing the analysis of the three-dimensional transient dynamic response of a Polycrystalline Diamond Compact Bit - Bit Sub arising from the intermittent contact of the bit with the downhole rock formations. The program accommodates non-linear, time dependent, loading and boundary conditions.

  4. A self propelled drilling system for hard-rock, horizontal and coiled tube drilling

    Biglin, D.; Wassell, M.


    Several advancements are needed to improve the efficiency and reliability of both hard rock drilling and extended reach drilling. This paper will present a Self Propelled Drilling System (SPDS) which can grip the borehole wall in order to provide a stable platform for the application of weight on bit (WOB) and resisting the reactive torque created by the downhole drilling motor, bit and formation interaction. The system will also dampen the damaging effects of drill string vibration. This tool employs two hydraulically activated anchors (front and rear) to grip the borehole wall, and a two-way thrust mandrel to apply both the drilling force to the bit, and a retraction force to pull the drill string into the hole. Forward drilling motion will commence by sequencing the anchor pistons and thrust mandrel to allow the tool to walk in a stepping motion. The SPDS has a microprocessor to control valve timing, sensing and communication functions. An optional Measurement While Drilling (MWD) interface can provide two-way communication of critical operating parameters such as hydraulic pressure and piston location. This information can then be telemetered to the surface, or used downhole to autonomously control system parameters such as anchor and thrust force or damping characteristics.

  5. Assessment of experimental thermal, numerical, and mandibular drilling factors in implantology.

    Pirjamalineisiani, A; Jamshidi, N; Sarafbidabad, M; Soltani, N


    The main factors that cause an increase in the temperature of the jaw during drilling when implanting teeth are the geometric measurements of the surgical drill, its rotational speed, and its feed rate (cutting speed). Using finite element modelling we analysed the effect of the three variables - the angle of the head of the drill bit, the rotational speed, and the feed rate - on the increase in the temperature of the bone at the point of the drill. This showed that drilling with the angle of the head of the drill bit at 70° generates a lower temperature than when it is at 90° or 118°. The same is true when the drill bit is set at 200 rotations/minute (rpm) compared with 400,800, or 1200rpm. When the feed rate of the drill bit is 120mm/minute it generates less heat than when it is at 90 or 60mm/minute. An increase in temperature during drilling of the jaw has a direct relation with the rotational speed of the drill bit, and a reverse relation to its feed rate. The sharper the drill bit, the lower the temperature during drilling.

  6. Evaluation of the parameters affecting bone temperature during drilling using a three-dimensional dynamic elastoplastic finite element model.

    Chen, Yung-Chuan; Tu, Yuan-Kun; Zhuang, Jun-Yan; Tsai, Yi-Jung; Yen, Cheng-Yo; Hsiao, Chih-Kun


    A three-dimensional dynamic elastoplastic finite element model was constructed and experimentally validated and was used to investigate the parameters which influence bone temperature during drilling, including the drill speed, feeding force, drill bit diameter, and bone density. Results showed the proposed three-dimensional dynamic elastoplastic finite element model can effectively simulate the temperature elevation during bone drilling. The bone temperature rise decreased with an increase in feeding force and drill speed, however, increased with the diameter of drill bit or bone density. The temperature distribution is significantly affected by the drilling duration; a lower drilling speed reduced the exposure duration, decreases the region of the thermally affected zone. The constructed model could be applied for analyzing the influence parameters during bone drilling to reduce the risk of thermal necrosis. It may provide important information for the design of drill bits and surgical drilling powers.

  7. Diamond Nanophotonics

    Aharonovich, Igor


    The burgeoning field of nanophotonics has grown to be a major research area, primarily because of the ability to control and manipulate single quantum systems (emitters) and single photons on demand. For many years studying nanophotonic phenomena was limited to traditional semiconductors (including silicon and GaAs) and experiments were carried out predominantly at cryogenic temperatures. In the last decade, however, diamond has emerged as a new contender to study photonic phenomena at the nanoscale. Offering plethora of quantum emitters that are optically active at room temperature and ambient conditions, diamond has been exploited to demonstrate super-resolution microscopy and realize entanglement, Purcell enhancement and other quantum and classical nanophotonic effects. Elucidating the importance of diamond as a material, this review will highlight the recent achievements in the field of diamond nanophotonics, and convey a roadmap for future experiments and technological advancements.

  8. Analysis of Button Bit Wear and Performance of Down-The-Hole ...

    Michael O. Mensah


    Dec 2, 2015 ... revealed that wear of rock drill bit is influenced by rock properties. .... oxide of 0.97%, chromium oxide, iron oxide, ... non-oxidised schist, silicon dioxide was again the ... minerals such as titanium oxide, chromium oxide,.

  9. Double acting bit holder

    Morrell, Roger J.; Larson, David A.; Ruzzi, Peter L.


    A double acting bit holder that permits bits held in it to be resharpened during cutting action to increase energy efficiency by reducing the amount of small chips produced. The holder consist of: a stationary base portion capable of being fixed to a cutter head of an excavation machine and having an integral extension therefrom with a bore hole therethrough to accommodate a pin shaft; a movable portion coextensive with the base having a pin shaft integrally extending therefrom that is insertable in the bore hole of the base member to permit the moveable portion to rotate about the axis of the pin shaft; a recess in the movable portion of the holder to accommodate a shank of a bit; and a biased spring disposed in adjoining openings in the base and moveable portions of the holder to permit the moveable portion to pivot around the pin shaft during cutting action of a bit fixed in a turret to allow front, mid and back positions of the bit during cutting to lessen creation of small chip amounts and resharpen the bit during excavation use.

  10. Downhole tools can increase deep drilling rig productivity

    Thiessen, D.A.; Doiron, H.H.


    Explains how there is much to be gained by better utilization of current drilling equipment, particularly for the much more expensive deep drilling. Optimized mud weight, better hydraulics, and higher rpm offer the best opportunities with increased bit weight as a fourth possibility. Current RandD in such areas as shock absorbers, downhole motors, new materials and designs for bits, and improved instrumentation will decrease drilling costs. Concludes that a reasonable projection is that drilling time for deep wells can be halved within the next decade.

  11. Berengario's drill: origin and inspiration.

    Chorney, Michael A; Gandhi, Chirag D; Prestigiacomo, Charles J


    Craniotomies are among the oldest neurosurgical procedures, as evidenced by early human skulls discovered with holes in the calvaria. Though devices change, the principles to safely transgress the skull are identical. Modern neurosurgeons regularly use electric power drills in the operating theater; however, nonelectric trephining instruments remain trusted by professionals in certain emergent settings in the rare instance that an electric drill is unavailable. Until the late Middle Ages, innovation in craniotomy instrumentation remained stunted without much documented redesign. Jacopo Berengario da Carpi's (c. 1457-1530 CE) text Tractatus de Fractura Calvae sive Cranei depicts a drill previously unseen in a medical volume. Written in 1518 CE, the book was motivated by defeat over the course of Lorenzo II de'Medici's medical care. Berengario's interchangeable bit with a compound brace ("vertibulum"), known today as the Hudson brace, symbolizes a pivotal device in neurosurgery and medical tool design. This drill permitted surgeons to stock multiple bits, perform the craniotomy faster, and decrease equipment costs during a period of increased incidence of cranial fractures, and thus the need for craniotomies, which was attributable to the introduction of gunpowder. The inspiration stemmed from a school of thought growing within a population of physicians trained as mathematicians, engineers, and astrologers prior to entering the medical profession. Berengario may have been the first to record the use of such a unique drill, but whether he invented this instrument or merely adapted its use for the craniotomy remains clouded.

  12. Forecasting the life of rock-bit journal bearings

    Kelly, J.L. (Hughes Tool Co. (US))


    This paper describes an analytical procedure for forecasting the life expectancy of rock-bit journal bearings. Actual performance data and reliability analyses are used to establish empirical relationships and a graphic procedure that relates the risk of bearing failure to operating parameters and drilling cost.

  13. Riserless drilling (managed pressure drilling)

    Khan, Ahsan


    There are several problems which an oil and gas industry is facing. These problems can be solved by riserless drilling method which comes under managed pressure drilling umbrella. The most important problem is increasing number of casing strings to complete a well and to control a well in limited pressure profile. A well model was developed and both conventional and riserless drilling approaches were applied to see how many casings will be needed to complete a same well with these approach...

  14. New optimized drill pipe size for deep-water, extended reach and ultra-deep drilling

    Jellison, Michael J.; Delgado, Ivanni [Grant Prideco, Inc., Hoston, TX (United States); Falcao, Jose Luiz; Sato, Ademar Takashi [PETROBRAS, Rio de Janeiro, RJ (Brazil); Moura, Carlos Amsler [Comercial Perfuradora Delba Baiana Ltda., Rio de Janeiro, RJ (Brazil)


    A new drill pipe size, 5-7/8 in. OD, represents enabling technology for Extended Reach Drilling (ERD), deep water and other deep well applications. Most world-class ERD and deep water wells have traditionally been drilled with 5-1/2 in. drill pipe or a combination of 6-5/8 in. and 5-1/2 in. drill pipe. The hydraulic performance of 5-1/2 in. drill pipe can be a major limitation in substantial ERD and deep water wells resulting in poor cuttings removal, slower penetration rates, diminished control over well trajectory and more tendency for drill pipe sticking. The 5-7/8 in. drill pipe provides a significant improvement in hydraulic efficiency compared to 5-1/2 in. drill pipe and does not suffer from the disadvantages associated with use of 6-5/8 in. drill pipe. It represents a drill pipe assembly that is optimized dimensionally and on a performance basis for casing and bit programs that are commonly used for ERD, deep water and ultra-deep wells. The paper discusses the engineering philosophy behind 5-7/8 in. drill pipe, the design challenges associated with development of the product and reviews the features and capabilities of the second-generation double-shoulder connection. The paper provides drilling case history information on significant projects where the pipe has been used and details results achieved with the pipe. (author)

  15. Long hole waterjet drilling for gas drainage

    Matt Stockwell; M. Gledhill; S. Hildebrand; S. Adam; Tim Meyer [CMTE (Australia)


    In-seam drilling for gas drainage is now an essential part of operations at many Australian underground coalmines. The objective of this project is to develop and trial a new drilling method for the accurate and efficient installation of long inseam boreholes (>1000 metres). This involves the integration of pure water-jet drilling technology (i.e. not water-jet assisted rotary drilling) developed by CMTE with conventional directional drilling technology. The system was similar to conventional directional drilling methods, but instead of relying on a down-hole-motor (DHM) rotating a mechanical drill bit for cutting, high pressure water-jets were used. The testing of the system did not achieve the full objectives set down in the project plan. A borehole greater than 1000 metres was not achieved. The first trial site had coal that was weathered, oxidized and dry. These conditions significantly affected the ability of the drilling tool to stay 'in-seam'. Due to the poor conditions at the first trial, many experimental objectives were forwarded to the second field trial. In the second trial drilling difficulties were experienced, this was due to the interaction between the confinement of the borehole and the dimensions of the down hole drilling assembly. This ultimately reduced the productivity of the system and the distance that could be drilled within the specified trial periods. Testing in the first field trial did not show any indication that the system would have this difficulty.

  16. Drill Embedded Nanosensors For Planetary Subsurface Exploration

    Li, Jing


    We have developed a carbon nanotube (CNT) sensor for water vapor detection under Martian Conditions and the miniaturized electronics can be embedded in the drill bit for collecting sensor data and transmit it to a computer wirelessly.This capability will enable the real time measurement of ice during drilling. With this real time and in-situ measurement, subsurface ice detection can be easy, fast, precise and low cost.

  17. Drilling reorganizes

    Richman, Barbara T.

    As the first in a proposed series of steps that would move scientific ocean drilling from its own niche within the National Science Foundation's (NSF) Directorate for Astronomical, Atmospheric, Earth, and Ocean Sciences (AAEO) into the agency's Division of Ocean Sciences, Grant Gross, division director, has been appointed acting director of the Office of Scientific Ocean Drilling (OSOD). Gross will retain the directorship of the division, which also is part of AAEO. Allen M. Shinn, Jr., OSOD director for nearly 2 years, has been reassigned effective July 10 to a position in NSF's Office of Planning and Resource Management.The move aims to tie drilling operations more closely to the science with which it is associated, Gross said. This first step is an organizational response to the current leaning toward using a commercial drilling vessel as the drilling platform, he said. Before the market for such commercial drill ships opened (Eos, February 22, 1983, p . 73), other ship options for scientific ocean drilling included refurbishing the aging Glomar Challenger or renovating, at great expense, the Glomar Explorer. A possible next step in the reorganization is to make OSOD the third section within the Ocean Sciences Division. Currently, the division is divided into the Oceanographic Facilities and Support Section and the Ocean Sciences Research Section.

  18. Performance Evaluation of Button Bits in Coal Measure Rocks by Using Multiple Regression Analyses

    Su, Okan


    Electro-hydraulic and jumbo drills are commonly used for underground coal mines and tunnel drives for the purpose of blasthole drilling and rock bolt installations. Not only machine parameters but also environmental conditions have significant effects on drilling. This study characterizes the performance of button bits during blasthole drilling in coal measure rocks by using multiple regression analyses. The penetration rate of jumbo and electro-hydraulic drills was measured in the field by employing bits in different diameters and the specific energy of the drilling was calculated at various locations, including highway tunnels and underground roadways of coal mines. Large block samples were collected from each location at which in situ drilling measurements were performed. Then, the effects of rock properties and machine parameters on the drilling performance were examined. Multiple regression models were developed for the prediction of the specific energy of the drilling and the penetration rate. The results revealed that hole area, impact (blow) energy, blows per minute of the piston within the drill, and some rock properties, such as the uniaxial compressive strength (UCS) and the drilling rate index (DRI), influence the drill performance.

  19. Drill System Development for the Lunar Subsurface Exploration

    Zacny, Kris; Davis, Kiel; Paulsen, Gale; Roberts, Dustyn; Wilson, Jack; Hernandez, Wilson

    Reaching the cold traps at the lunar poles and directly sensing the subsurface regolith is a primary goal of lunar exploration, especially as a means of prospecting for future In Situ Resource Utilization efforts. As part of the development of a lunar drill capable of reaching a depth of two meters or more, Honeybee Robotics has built a laboratory drill system with a total linear stroke of 1 meter, capability to produce as much as 45 N-m of torque at a rotational speed of 200 rpm, and a capability of delivering maximum downforce of 1000 N. Since this is a test-bed, the motors were purposely chosen to be relative large to provide ample power to the drill system (the Apollo drill was a 500 Watt drill, i.e. not small in current standards). In addition, the drill is capable of using three different drilling modes: rotary, rotary percussive and percussive. The frequency of percussive impact can be varied if needed while rotational speed can be held constant. An integral part of this test bed is a vacuum chamber that is currently being constructed. The drill test-bed is used for analyzing various drilling modes and testing different drill bit and auger systems under low pressure conditions and in lunar regolith simulant. The results of the tests are used to develop final lunar drill design as well as efficient drilling protocols. The drill was also designed to accommodate a downhole neutron spectrometer for measuring the amount of hydrated material in the area surrounding the borehole, as well as downhole temperature sensors, accelerometers, and electrical properties tester. The presentation will include history of lunar drilling, challenges of drilling on the Moon, a description of the drill and chamber as well as preliminary drilling test results conducted in the ice-bound lunar regolith simulant with a variety of drill bits and augers systems.

  20. Steerable percussion air drilling system

    Bui, H.D.; Oliver, M.S.; Gray, M.A.


    The cost-sharing contract between the US Department of Energy and Smith International provides the funding to further develop this concept into two complete steerable percussion air drilling system prototypes, each integrated with a navigation tool (wireline steering tool), a bend sub, stabilizing devices, and to conduct laboratory and field testing necessary to prepare the system for commercial realization. Such a system would make available for the first time the ability to penetrate earthen formations by the percussion method, using compressed air as the drilling fluid, and at the same time allow the directional control and steering of the drill bit. While the drill string is not rotating (slide mode), one can orient to build angle in the desired direction at a predictable rate. This build rate can be in the range of 1--20 degrees per one hundred feet and proceeds until the desired inclination or direction has been obtained. The drill pipe is then set in rotation, nullifying the effect of the bend angle, and causes the assembly to drill straight. The sliding procedure can be repeated as often as corrections for hole`s inclination or direction are needed.

  1. Environmental Measurement-While-Drilling System and Horizontal Directional Drilling Technology Demonstration, Hanford Site

    Williams, C.V.; Lockwood, G.J.; Normann, R.A.; Myers, D.A.; Gardner, M.G.; Williamson, T.; Huffman, J.


    The Environmental Measurement-While-Drilling (EMWD) system and Horizontal Directional Drilling (HDD) were successfully demonstrated at the Mock Tank Leak Simulation Site and the Drilling Technology Test Site, Hanford, Washington. The use of directional drilling offers an alternative to vertical drilling site characterization. Directional drilling can develop a borehole under a structure, such as a waste tank, from an angled entry and leveling off to horizontal at the desired depth. The EMWD system represents an innovative blend of new and existing technology that provides the capability of producing real-time environmental and drill bit data during drilling operations. The technology demonstration consisted of the development of one borehole under a mock waste tank at a depth of {approximately} {minus}8 m ({minus}27 ft.), following a predetermined drill path, tracking the drill path to within a radius of {approximately}1.5 m (5 ft.), and monitoring for zones of radiological activity using the EMWD system. The purpose of the second borehole was to demonstrate the capability of drilling to a depth of {approximately} {minus}21 m ({minus}70 ft.), the depth needed to obtain access under the Hanford waste tanks, and continue drilling horizontally. This report presents information on the HDD and EMWD technologies, demonstration design, results of the demonstrations, and lessons learned.

  2. Investigation on drilling-grinding of CFRP

    Yanming QUAN; Wenwang ZHONG


    It is difficult to machine polymer matrix composites reinforced by carbon fibre, and the hole-making process is the most necessary machining process for composite plate products. Conventional drills have a very short life in the drilling of this kind of composites and the quality of the hole is very poor. In this paper, the cemented or plated diamond core tools are tested to make holes in carbon fibre/epoxy composite plates. The effects of machining parameters, cooling and chip removal on the tool life, and the hole quality are investigated. The results indicate that the material removal mechanism of the two kinds of diamond tools is not like the cutting effect of the conventional drilling but similar to that of grinding. Satisfactory effects in making holes in the composites are obtained--quite acceptable machined hole quality, low costs, and long wear-resistant endurance.

  3. Boring and Drilling Tools. Pre-Apprenticeship Phase 1 Training.

    Lane Community Coll., Eugene, OR.

    This self-paced student training module on boring and drilling tools is one of a number of modules developed for Pre-apprenticeship Phase 1 Training. Purpose of the module is to enable students to identify, select, and understand the proper use of many common awls, bits, and drilling tools. The module may contain some or all of the following: a…

  4. Superhard nanophase materials for rock drilling applications

    Sadangi, R.K.; Voronov, O.A.; Tompa, G.S. [Diamond Materials Inc., Pisctaway, NJ (United States); Kear, B.H. [Rutgers Univ., Piscataway, NJ (United States)


    Diamond Materials Incorporated is developing new class of superhard materials for rock drilling applications. In this paper, we will describe two types of superhard materials, (a) binderless polycrystalline diamond compacts (BPCD), and (b) functionally graded triphasic nanocomposite materials (FGTNC). BPCDs are true polycrystalline diamond ceramic with < 0.5 wt% binders and have demonstrated to maintain their wear properties in a granite-log test even after 700{degrees}C thermal treatment. FGTNCs are functionally-graded triphasic superhard material, comprising a nanophase WC/Co core and a diamond-enriched surface, that combine high strength and toughness with superior wear resistance, making FGTNC an attractive material for use as roller cone stud inserts.

  5. An assembly for the bottom of a drilling column

    Gerzhberg, Yu.M.; Akopov, E.A.; Avakyan, T.G.; Gadzhiyev, N.S.; Nikitin, B.A.; Pototskiy, A.I.; Zakharov, B.I.


    An assembly is proposed for the bottom of a drill string, which includes a slag trap, an extender, adapters and a bit. It is distinguished by the fact that in order to increase the effectiveness of drilling through improving the wash out of the bottom hole and preventing the formation of stuffing on the bit, it is equipped with a splitter installed between the bit and the slag trap which has an exterior diameter equal to the exterior diameter of the slag trap. The splitter is installed with the capability of interaction with the housing of the slag trap along the faces, where the latter is conical.

  6. Wellbore Surveying While Drilling Based on Kalman Filtering

    Mahmoud ElGizawy


    Full Text Available Problem statement: Oil and gas are global fuels obtained primarily from drilling wells in underground terrestrial reservoirs. Vertical drilling is preferred because of its simplicity and therefore low cost, but subsurface targets can often be procured only by directing the wellbore along predefined non-vertical trajectories. For instance, directional drilling must be employed to reach locations inaccessible to the drilling rig, to side track an existing well (multilateral drilling, or to drill multiple wells from the same offshore platform (horizontal drilling. Approach: A complete knowledge of the wellbore direction and orientation during the drilling process is essential to guarantee proper directional drilling procedure. Results: Thus, besides the conventional drilling assembly, directional drilling operations require sensors to provide azimuth, inclination and toolface angles of the drill. These sensors are part of the Measurement-While-Drilling (MWD tool, which in current technology is installed several feet behind the drill bit. In such systems, values for inclination and toolface angles are determined from accelerometer measurements at predetermined stationary surveying stations; these values are then incorporated with magnetometer measurements to deliver the azimuth angle. Values for inclination and azimuth angles at the current surveying station are combined with those from the previous station to compute the position of the probe. However, there is no accurate information about the wellbore trajectory between survey stations. Additionally, the magnetic field of the magnetometers has deleterious effect on the overall accuracy of surveying measurements. Conclusion: A method to provide continuous information about the wellbore trajectory has been developed in this study. The module developed integrates a Rotary Steerable System (RSS and MWD tool into one drilling probe utilizing Inertial Navigation System (INS technology. This is achieved

  7. Prediction of the temperature of a drill in drilling lunar rock simulant in a vacuum

    Cui Jinsheng


    Full Text Available In this article, the temperature of a sampling drill in drilling lunar rock simulant in a high-vacuum environment was studied. The thermal problem was viewed as a 1-D transient heat transfer problem in a semi-infinite object. The simplified drill was modeled using heat conduction differential equation and a fast numerical calculation method is proposed on this basis, with time and the drill discretized. The model was modified to consider the effects of radiation, drill bit configuration, and non-constant heat source. A thermal analysis was conducted using ANSYS Workbench to determine the value of the equivalent correction coefficient proposed in this paper. Using fiber Bragg grating temperature measurement method, drilling experiments were conducted in a vacuum, and the results were compared to the model. The agreement between model and experiment was very good.

  8. Foldable Instrumented Bits for Ultrasonic/Sonic Penetrators

    Bar-Cohen, Yoseph; Badescu, Mircea; Iskenderian, Theodore; Sherrit, Stewart; Bao, Xiaoqi; Linderman, Randel


    Long tool bits are undergoing development that can be stowed compactly until used as rock- or ground-penetrating probes actuated by ultrasonic/sonic mechanisms. These bits are designed to be folded or rolled into compact form for transport to exploration sites, where they are to be connected to their ultrasonic/ sonic actuation mechanisms and unfolded or unrolled to their full lengths for penetrating ground or rock to relatively large depths. These bits can be designed to acquire rock or soil samples and/or to be equipped with sensors for measuring properties of rock or soil in situ. These bits can also be designed to be withdrawn from the ground, restowed, and transported for reuse at different exploration sites. Apparatuses based on the concept of a probe actuated by an ultrasonic/sonic mechanism have been described in numerous prior NASA Tech Briefs articles, the most recent and relevant being "Ultrasonic/ Sonic Impacting Penetrators" (NPO-41666) NASA Tech Briefs, Vol. 32, No. 4 (April 2008), page 58. All of those apparatuses are variations on the basic theme of the earliest ones, denoted ultrasonic/sonic drill corers (USDCs). To recapitulate: An apparatus of this type includes a lightweight, low-power, piezoelectrically driven actuator in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary twist drilling, ordinary hammering, or ordinary steady pushing. Examples of properties that could be measured by use of an instrumented tool bit include electrical conductivity, permittivity, magnetic

  9. Rotary and Rotary-Percussive Drilling of Lunar Simulant

    Paulsen, G.; Zacny, K.; Maksymuk, M.; Wilson, J.; Santoro, C.; Chu, P.; Davis, K.; Roberts, D.; Kumar, N.; Kusack, A.


    Honeybee Robotics has been developing a rotary and a rotary-preliminary drill system for planetary exploration. This is a test drill with a power rating of 1000 Watt, whose purpose it to test various drill bits and augers in rotary and rotary percussive operation. It is not optimized for power or mass but rather to acquire qualitative drilling data such as penetration rate, power, and torque, temperature, Weight on Bit, vibration energy and others. In addition, the design of the drill allows it to acquire drill bit temperatures and use pneumatic system (instead of augers) for removing of rock cuttings. The drill is designed to have a 1 meter stroke. In addition to the drill system, we have been developing a matching split vacuum chamber, which is 3ft wide, 3ft deep and 11 feet tall. The chamber consists of two smaller chambers (84 inches tall and 48 inches tall) assembled on top of each other. This allows for additional flexibility if only a smaller chamber is required for some testing. The chamber will be able to maintain pressure of below 1 torr. Maintaining sample temperature will be achieved by closed loop cooling system down to -40C or by using liquid nitrogen that allows a temperature of 77K. The test samples can be varied raging from solid rocks, to loose soils to icy soils and pure ice. The sample holder could also be integrated with temperatures for acquiring of thermal data during drilling process.

  10. Two-Bit Bit Flipping Decoding of LDPC Codes

    Nguyen, Dung Viet; Marcellin, Michael W


    In this paper, we propose a new class of bit flipping algorithms for low-density parity-check (LDPC) codes over the binary symmetric channel (BSC). Compared to the regular (parallel or serial) bit flipping algorithms, the proposed algorithms employ one additional bit at a variable node to represent its "strength." The introduction of this additional bit increases the guaranteed error correction capability by a factor of at least 2. An additional bit can also be employed at a check node to capture information which is beneficial to decoding. A framework for failure analysis of the proposed algorithms is described. These algorithms outperform the Gallager A/B algorithm and the min-sum algorithm at much lower complexity. Concatenation of two-bit bit flipping algorithms show a potential to approach the performance of belief propagation (BP) decoding in the error floor region, also at lower complexity.

  11. Innovative collaboration important to rotary steerable drilling



    Sperry-Sun Drilling Services' recently commercialized Geo-Pilot{sup T}M rotary steerable drilling system is described. The system consists of the Geo-Pilot{sup T}M rotary steerable tool, a logging-while-drilling (LWD) system, specially designed long-gauge bits and the INSITE{sup T}M data acquisition and management system. The system brings a completely new approach to rotary steerable drilling. It uses 'point-the-bit' technology to deflect a rotating drive shaft off center, causing the drive shaft to flex and alter the direction of the drilling. The tool provides real-time steering information and at-bit inclination measurement, both of which are integrated with the INSITE{sup T}M rig information system. The real-time data can be displayed along with other formation evaluation information. The system has been evaluated at the Gas Research Institute's Oklahoma test facility; it has been used commercially by Canadian, Norwegian and US operators, with complete success. Worldwide deployment of the system is in the planning stages.

  12. Peculiarities of carbon fiber drilling

    Ruslan Yu. Melentiev


    Full Text Available At polymeric composite materials (PCM machining we face a number of specific features. The research refers to PCMs classification, exposing an overview of known specific features described in the latest advances and techniques to improve the quality and efficiency in PCM processing. To study the carbon fiber drilling a preliminary experiment has been conducted, which essential parameters and issues have been described with respective data Tables and numerous images. The holes surface quality and edges dimensional accuracy have been compared for samples obtained using a blade and a diamond tool; established is the instrument blade material impact on the edges’ precision parameters. Confirmed are the typical and revealed some new types of imperfections and their occurrence conditions. The problem of rapid clogging and related diamond tool clogging problem are identified. Some promising ways of processing of carbon fiber are offered.

  13. Evaluation of Bit Preservation Strategies

    Zierau, Eld; Kejser, Ulla Bøgvad; Kulovits, Hannes


    This article describes a methodology which supports evaluation of bit preservation strategies for different digital materials. This includes evaluation of alternative bit preservation solution. The methodology presented uses the preservation planning tool Plato for evaluations, and a BR......-ReMS prototype to calculate measures for how well bit preservation requirements are met. Planning storage of data as part of preservation planning involves classification of data with regard to requirements on confidentiality, bit safety, available and costs. Choice of storage with such parameters is quite...... complex since e.g. more copies of data means better bit safety, but higher cost and bigger risk of breaking confidentiality. Based on a case of a bit repository offering varied bit preservation solutions, the article will present results of using the methodology to make plans and choices of alternatives...

  14. Positional information, in bits.

    Dubuis, Julien O; Tkacik, Gasper; Wieschaus, Eric F; Gregor, Thomas; Bialek, William


    Cells in a developing embryo have no direct way of "measuring" their physical position. Through a variety of processes, however, the expression levels of multiple genes come to be correlated with position, and these expression levels thus form a code for "positional information." We show how to measure this information, in bits, using the gap genes in the Drosophila embryo as an example. Individual genes carry nearly two bits of information, twice as much as would be expected if the expression patterns consisted only of on/off domains separated by sharp boundaries. Taken together, four gap genes carry enough information to define a cell's location with an error bar of ~1 along the anterior/posterior axis of the embryo. This precision is nearly enough for each cell to have a unique identity, which is the maximum information the system can use, and is nearly constant along the length of the embryo. We argue that this constancy is a signature of optimality in the transmission of information from primary morphogen inputs to the output of the gap gene network.

  15. Robust relativistic bit commitment

    Chakraborty, Kaushik; Chailloux, André; Leverrier, Anthony


    Relativistic cryptography exploits the fact that no information can travel faster than the speed of light in order to obtain security guarantees that cannot be achieved from the laws of quantum mechanics alone. Recently, Lunghi et al. [Phys. Rev. Lett. 115, 030502 (2015), 10.1103/PhysRevLett.115.030502] presented a bit-commitment scheme where each party uses two agents that exchange classical information in a synchronized fashion, and that is both hiding and binding. A caveat is that the commitment time is intrinsically limited by the spatial configuration of the players, and increasing this time requires the agents to exchange messages during the whole duration of the protocol. While such a solution remains computationally attractive, its practicality is severely limited in realistic settings since all communication must remain perfectly synchronized at all times. In this work, we introduce a robust protocol for relativistic bit commitment that tolerates failures of the classical communication network. This is done by adding a third agent to both parties. Our scheme provides a quadratic improvement in terms of expected sustain time compared with the original protocol, while retaining the same level of security.

  16. Laser Drilling Practical Applications

    Yilbas, Bekir Sami


    This book introduces laser drilling processes including modelling, quality assessment of drilled holes, and laser drilling applications. It provides insights into the laser drilling process and the relation among the drilling parameters pertinent to improved end product quality. This book is written for engineers and scientists working on laser machining, particularly laser drilling.

  17. Experimental Investigation on the Performance of Grinding Assisted Electrochemical Discharge Drilling of Glass

    Ladeesh V. G.; Manu R


    Grinding assisted electrochemical discharge drilling (G-ECDD) is a novel technique for producing micro and macro holes in brittle materials including advanced ceramics and glass, both efficiently and economically. G-ECDD involves the use of a rotating diamond core drill as the tool in a normal electrochemical discharge machine setup. The material removal happens by a combination of thermal melting due to electric discharges, followed by grinding action of diamond grits and chemical etching ac...

  18. Drilling optimized by monitoring BHA dynamics with MWD

    Sutcliffe, B. (Teleco Oilfield Services Inc., Aberdeen (GB)); Sim, D. (Teleco Oilfield Services Inc., Meriden, CT (US))


    By measuring the drilling performance of the bottom hole assembly (BHA) in real time, the probability of serious drilling problems can be reduced. A new logging tool and service directly measures bottom hole assembly performance, thus allowing swifter and more accurate corrective measures when necessary. Drilling time savings are realized through improved rates of penetration (ROP), reduced off-bottom time, and increase life of drillstring. Advances in measurement-while-drilling (MWD) technology have facilitated the inclusion of downhole drilling dynamics measurements into the package of MWD data transmitted in real time. Thus, the actual energy input to the bit and the resistance of the formation to drilling can be measured and compared to the surface data. This provides an extremely useful analytical tool for the drilling engineer.

  19. Evaluation of Bit Preservation Strategies

    Zierau, Eld; Kejser, Ulla Bøgvad; Kulovits, Hannes


    This article describes a methodology which supports evaluation of bit preservation strategies for different digital materials. This includes evaluation of alternative bit preservation solution. The methodology presented uses the preservation planning tool Plato for evaluations, and a BR...... for different digital material with different requirements for bit integrity and confidentiality. This case shows that the methodology, including the tools used, is useful for this purpose....

  20. Integral analysis of the drill string dynamic behaviour to optimize drilling operation; Analise integrada do comportamento dinamico da coluna para otimizacao de perfuracao

    Lima, Araken [Smith International do Brasil, Macae, RJ (Brazil); Placido, Joao C.R.; Percy, Joseir G.; Falcao, Jose; Freire, Helena; Ono, Eduardo H.; Masculo, Miguel S. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Azuaga, Denise; Frenzel, Mark [Smith International Inc., Houston, TX (United States)


    For a performance preview of a drilling system is necessary a dynamic and integrated modeling for understanding all system forces resulting from the combination of the rock strength, cut structure action, drilling parameters, BHA and all others drilling components. This study must predict, for the drill string, vibrations and torsions, from bit to surface, its origins and its effects, and provides the best way to reduce these vibrations, determining the best bit, BHA and drilling parameters. Thereby, this study eliminates the trial and error approach and the operation risks. This paper aims to present studies of optimization for two drilling wells conducted in Brazil, one in Santos Basin and other in Campos Basin, and compares the numerical simulations results with the data from drilling operations. (author)

  1. Bucket drill

    Bezverkhiy, V.M.; Nabokov, I.M.; Podoksik, D.Z.; Sadovskiy, S.S.; Shanyukevich, V.A.


    The bucket drill including a cylindrical housing with bottom, ground intake windows and cutting knives is hinged to the housing, the mechanism of rotation of the cutting knives including rods connected by the cutter knives, and drive shaft is distinguished by the fact that in order to improve the effectiveness of drilling by automatic change in the angle of cutting depending on the strength of the drillable rock, the drill is equipped with elastic elements and cap with annular slits in which there are elastic elements. The mechanism of rotation of the cutting knives is equipped with levers hinged to the housing, pins with shaft and rocker arm. The rods are made with a slit and from one end are rigidly connected to the cutting knives, and from the other end to the levers by means of pins which are arranged in slits of the rod with the possibility of movement. The upper ends of the levers are installed with the possibility of movement in the pins whose shafts are arranged with the possibility of rotation in the rocker arm rigidly connected to the drive shaft. The drive shaft is equipped with cantilevers installed in the cap with the possibility of rotation and interaction with the elastic elements.

  2. Optimization of Mud Hammer Drilling Performance--A Program to Benchmark the Viability of Advanced Mud Hammer Drilling

    Arnis Judzis


    Operators continue to look for ways to improve hard rock drilling performance through emerging technologies. A consortium of Department of Energy, operator and industry participants put together an effort to test and optimize mud driven fluid hammers as one emerging technology that has shown promise to increase penetration rates in hard rock. The thrust of this program has been to test and record the performance of fluid hammers in full scale test conditions including, hard formations at simulated depth, high density/high solids drilling muds, and realistic fluid power levels. This paper details the testing and results of testing two 7 3/4 inch diameter mud hammers with 8 1/2 inch hammer bits. A Novatek MHN5 and an SDS Digger FH185 mud hammer were tested with several bit types, with performance being compared to a conventional (IADC Code 537) tricone bit. These tools functionally operated in all of the simulated downhole environments. The performance was in the range of the baseline ticone or better at lower borehole pressures, but at higher borehole pressures the performance was in the lower range or below that of the baseline tricone bit. A new drilling mode was observed, while operating the MHN5 mud hammer. This mode was noticed as the weight on bit (WOB) was in transition from low to high applied load. During this new ''transition drilling mode'', performance was substantially improved and in some cases outperformed the tricone bit. Improvements were noted for the SDS tool while drilling with a more aggressive bit design. Future work includes the optimization of these or the next generation tools for operating in higher density and higher borehole pressure conditions and improving bit design and technology based on the knowledge gained from this test program.

  3. Demonstration of bit torque, load, RPM and survey tool

    Ian Gray; Paul Clemence; Gary Paradise; Sean Charlton; Robert Dixon; Peter Hatherly [Sigra (Australia)


    In 1996, Sigra and CMTE began a joint research project aimed at developing a tool to provide geosteering options for in-seam drilling. The tool was to provide a survey capability, drill torque, thrust and rpm measurements, and geophysical measurements of rock resistivity and the spectrum of the natural gamma radiation. It was intended that the tool could reside behind the drill bit and communicate through the drill string via existing communication systems or a cableless system that Sigra was proposing to develop. The development of geosteering tools has proved to be far more difficult than originally expected. The results from various tests, however, are extremely encouraging. Sigra has demonstrated the acquisition of rock resistivity and drill parameters - torque, pressure and thrust while drilling is underway. The expectation is that the resistivity measurements can indicate the approach of the coal seam roof or floor from the borehole. CMTE has established through the logging of in-seam and vertical boreholes, that spectrometric analysis of natural gamma radiation allows a characteristic seam profile to be monitored and that stone bands in the seam can be distinguished from the roof and floor. The ratio of the counts due to thorium and potassium is particularly diagnostic when combined with the information on the total radiation. All tools have been designed and constructed in consideration of the rigours of the down-hole environment, the needs for intrinsic safety, the needs for power, modularity, down-hole processing and communications.

  4. Field application of a fully rotating point-the-bit rotary steerable system (SPE 67716)

    Schaaf, S.; Pafitis, D. [Schlumberger Canada Ltd., Calgary, AB (Canada)


    Petroleum offshore operations can encounter downhole sliding problems related to maintaining drilling bit orientation, low effective ROP, poor hole cleaning and the inability of the bit to slide. Other problems include differential sticking, buckling, lock-up, high tortuosity, and build-up rate formation sensitive. Several illustrations were presented indicating ways to correct problems with the bit system through better steerability and orientation of the motors. Specifications and field test examples were presented. One of the test examples involved a land operation in California and another involved a vertical well in a strongly dipping formation. The success of the field tests proved the steering concept of an internally off-set drive-shaft. The point-the-bit rotary steerable system contains no stationary components in contact with the formation. In addition, the tool can be drilled at a tangent to the formation. The tests demonstrated that the system is reliable in experimental design. tabs., figs.

  5. Single Piezo-Actuator Rotary-Hammering Drill

    Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph


    This innovation comprises a compact drill that uses low-axial preload, via vibrations, that fractures the rock under the bit kerf, and rotates the bit to remove the powdered cuttings while augmenting the rock fracture via shear forces. The vibrations fluidize the powered cuttings inside the flutes around the bit, reducing the friction with the auger surface. These combined actions reduce the consumed power and the heating of the drilled medium, helping to preserve the pristine content of the produced samples. The drill consists of an actuator that simultaneously impacts and rotates the bit by applying force and torque via a single piezoelectric stack actuator without the need for a gearbox or lever mechanism. This reduces the development/fabrication cost and complexity. The piezoelectric actuator impacts the surface and generates shear forces, fragmenting the drilled medium directly under the bit kerf by exceeding the tensile and/or shear strength of the struck surface. The percussive impact action of the actuator leads to penetration of the medium by producing a zone of finely crushed rock directly underneath the struck location. This fracturing process is highly enhanced by the shear forces from the rotation and twisting action. To remove the formed cuttings, the bit is constructed with an auger on its internal or external surface. One of the problems with pure hammering is that, as the teeth become embedded in the sample, the drilling efficiency drops unless the teeth are moved away from the specific footprint location. By rotating the teeth, they are moved to areas that were not fragmented, and thus the rock fracturing is enhanced via shear forces. The shear motion creates ripping or chiseling action to produce larger fragments to increase the drilling efficiency, and to reduce the required power. The actuator of the drill consists of a piezoelectric stack that vibrates the horn. The stack is compressed by a bolt between the backing and the horn in order to

  6. Hey! A Tarantula Bit Me!

    ... it or try to play with it. These spiders will not bite you unless they feel threatened — if you leave them alone, they will leave you alone. For Teens For ... Stung Me! Hey! A Scorpion Stung Me! Hey! A Black Widow Spider Bit Me! Hey! A Brown Recluse Spider Bit ...

  7. Considerations, constraints and strategies for drilling on Mars

    Zacny, K.; Cooper, G.


    The effect of the environmental conditions on Mars - low temperature, low pressure, the uncertainty in the nature of the formations to be penetrated and the possibility of encountering ice - imply that a successful drilling system will have to be able to cope with a wide range of conditions. Systems using continuous drill pipe or wireline both offer attractive features and disadvantages, and the preferred choice may depend on the target depth. The drill bit will have to cope with a range of terrain, and we offer some suggestions for making a bit that will be able to drill in both hard and soft formations, and also be able to resist choking if it encounters ice or ice-bound materials. Since it will not be possible to use a liquid to remove the drilled cuttings on Mars, the cuttings removal system will probably use some form of auger, although it may be possible to use continuous or intermittent gas blasts. The sublimation of ice resulting from the heat of drilling in ice-containing formations may help in removing the cuttings, particularly as they are expected to be very fine as a result of the low power available for drilling. Drilling into ice bound soils was also found to be akin to drilling into ice-bound sandstones.

  8. Experimental unconditionally secure bit commitment

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adan; Pan, Jian-Wei


    Quantum physics allows unconditionally secure communication between parties that trust each other. However, when they do not trust each other such as in the bit commitment, quantum physics is not enough to guarantee security. Only when relativistic causality constraints combined, the unconditional secure bit commitment becomes feasible. Here we experimentally implement a quantum bit commitment with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. Bits are successfully committed with less than 5 . 68 ×10-2 cheating probability. This provides an experimental proof of unconditional secure bit commitment and demonstrates the feasibility of relativistic quantum communication.

  9. Drilling Penetration Rate Estimation using Rock Drillability Characterization Index

    Taheri, Abbas; Qao, Qi; Chanda, Emmanuel


    Rock drilling Penetration Rate (PR) is influenced by many parameters including rock properties, machine parameters of the chosen rig and the working process. Five datasets were utilized to quantitatively assess the effect of various rock properties on PR. The datasets consisted of two sets of diamond and percussive drilling and one set of rotary drilling data. A new rating system called Rock Drillability Characterization index (RDCi) is proposed to predict PR for different drilling methods. This drillability model incorporates the uniaxial compressive strength of intact rock, the P-wave velocity and the density of rock. The RDCi system is further applied to predict PR in the diamond rotary drilling, non-coring rotary drilling and percussive drilling. Strong correlations between PR and RDCi values were observed indicating that the developed drillability rating model is relevant and can be utilized to effectively predict the rock drillability in any operating environment. A practical procedure for predicting PR using the RDCi was established. The drilling engineers can follow this procedure to use RDCi as an effective method to estimate drillability.

  10. The Auto-Gopher Deep Drill

    Badescu, Mircea


    Subsurface penetration by coring, drilling or abrading is of great importance for a large number of space and earth applications. An Ultrasonic/Sonic Drill/Corer (USDC) has been in development at JPL's Nondestructive Evaluation and Advanced Actuators (NDEAA) lab as an adaptable tool for many of these applications. The USDC uses a novel drive mechanism to transform the high frequency ultrasonic or sonic vibrations of the tip of a horn into a lower frequency sonic hammering of a drill bit through an intermediate free-flying mass. The USDC device idea has been implemented at various scales from handheld drills to large diameter coring devices. A series of computer programs that model the function and performance of the USDC device were developed and were later integrated into an automated modeling package. The USDC has also evolved from a purely hammering drill to a rotary hammer drill as the design requirements increased form small diameter shallow drilling to large diameter deep coring. A synthesis of the Auto-Gopher development is presented in this paper.

  11. Drilling equipment

    Voyevodin, Yu.M.; Kholosha, Ye.G.; Leshchenko, A.G.; Timchenko, A.I.


    The invention refers to units designed for extracting minerals by mechanical action on the face by a cutting tool. There is a known drills which includes a pulse device which contains a combustion chamber, cylinder, piston-percussion tool and cutting tool. The combustion chamber and the sub-piston cavity of the cylinder are connected by a channel in which there is a distributor. Its shortcoming is the fact that the pulse device does not guarantee the necessary motion of the actuating mechanism for its velocity and frequency of the shocks on the cutting tool. This reduces the efficiency of the operation and limits the area of application. The purpose of the proposed invention is to improve productivity of the device. This is achieved because the head of the drill is equipped with a 2-piston pulse device which contains 2-combustion chambers, 2 working cylinders, 2 piston percussion instruments, a rod with gas-conducting and connecting channels for interconnection of the sub-piston cavities and combustion chambers of both cylinders. The spent gases of one cylinder are used for closing the combustion chamber of the second cylinder.

  12. Bit Preservation: A Solved Problem?

    David S. H. Rosenthal


    Full Text Available For years, discussions of digital preservation have routinely featured comments such as “bit preservation is a solved problem; the real issues are ...”. Indeed, current digital storage technologies are not just astoundingly cheap and capacious, they are astonishingly reliable. Unfortunately, these attributes drive a kind of “Parkinson’s Law” of storage, in which demands continually push beyond the capabilities of systems implementable at an affordable price. This paper is in four parts:Claims, reviewing a typical claim of storage system reliability, showing that it provides no useful information for bit preservation purposes.Theory, proposing “bit half-life” as an initial, if inadequate, measure of bit preservation performance, expressing bit preservation requirements in terms of it, and showing that the requirements being placed on bit preservation systems are so onerous that the experiments required to prove that a solution exists are not feasible.Practice, reviewing recent research into how well actual storage systems preserve bits, showing that they fail to meet the requirements by many orders of magnitude.Policy, suggesting ways of dealing with this unfortunate situation.

  13. low bit rate video coding low bit rate video coding


    ariable length bit rate (VLBR) broadly encompasses video coding which broadly encompasses ... for motion estimation and compensation to reduce the prediction sation to reduce the ... a special interest among the video coding community ...

  14. A Study of Specific Fracture Energy at Percussion Drilling

    A, Shadrina; T, Kabanova; V, Krets; L, Saruev


    The paper presents experimental studies of rock failure provided by percussion drilling. Quantification and qualitative analysis were carried out to estimate critical values of rock failure depending on the hammer pre-impact velocity, types of drill bits and cylindrical hammer parameters (weight, length, diameter), and turn angle of a drill bit. Obtained data in this work were compared with obtained results by other researchers. The particle-size distribution in granite-cutting sludge was analyzed in this paper. Statistical approach (Spearmen's rank-order correlation, multiple regression analysis with dummy variables, Kruskal-Wallis nonparametric test) was used to analyze the drilling process. Experimental data will be useful for specialists engaged in simulation and illustration of rock failure.

  15. Geothermal well technology: drilling and completions program plan

    Newsom, M.M.; Barnett, J.H.; Baker, L.E.; Varnado, S.G.; Polito, J.


    The drilling and completion portion of the long-range Geothermal Well Technology Program is presented. A nine-year program is outlined based upon an objective of reducing the cost of geothermal energy development and providing a major stimulus to meeting the power-on-line goals established by the Department of Energy. Major technological challenges to be addressed in this program include improvements in geothermal drilling fluids, downhole drilling motors, rock bits and the development of high flow rate, high temperature completion and reinjection techniques. In addition, fundamental studies will be conducted in drilling energetics to improve the understanding of drilling mechanics. This will lead to advanced development of high performance, low cost geothermal drilling systems.

  16. Advanced Seismic While Drilling System

    Robert Radtke; John Fontenot; David Glowka; Robert Stokes; Jeffery Sutherland; Ron Evans; Jim Musser


    A breakthrough has been discovered for controlling seismic sources to generate selectable low frequencies. Conventional seismic sources, including sparkers, rotary mechanical, hydraulic, air guns, and explosives, by their very nature produce high-frequencies. This is counter to the need for long signal transmission through rock. The patent pending SeismicPULSER{trademark} methodology has been developed for controlling otherwise high-frequency seismic sources to generate selectable low-frequency peak spectra applicable to many seismic applications. Specifically, we have demonstrated the application of a low-frequency sparker source which can be incorporated into a drill bit for Drill Bit Seismic While Drilling (SWD). To create the methodology of a controllable low-frequency sparker seismic source, it was necessary to learn how to maximize sparker efficiencies to couple to, and transmit through, rock with the study of sparker designs and mechanisms for (a) coupling the sparker-generated gas bubble expansion and contraction to the rock, (b) the effects of fluid properties and dynamics, (c) linear and non-linear acoustics, and (d) imparted force directionality. After extensive seismic modeling, the design of high-efficiency sparkers, laboratory high frequency sparker testing, and field tests were performed at the University of Texas Devine seismic test site. The conclusion of the field test was that extremely high power levels would be required to have the range required for deep, 15,000+ ft, high-temperature, high-pressure (HTHP) wells. Thereafter, more modeling and laboratory testing led to the discovery of a method to control a sparker that could generate low frequencies required for deep wells. The low frequency sparker was successfully tested at the Department of Energy Rocky Mountain Oilfield Test Center (DOE RMOTC) field test site in Casper, Wyoming. An 8-in diameter by 26-ft long SeismicPULSER{trademark} drill string tool was designed and manufactured by TII

  17. Hey! A Gnat Bit Me!

    ... Hey! A Bee Stung Me! Rashes: The Itchy Truth Hey! A Mosquito Bit Me! Contact Us Print ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...

  18. Hey! A Louse Bit Me!

    ... Hey! A Chigger Bit Me! Rashes: The Itchy Truth Contact Us Print Resources Send to a Friend ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...

  19. Hey! A Bedbug Bit Me!

    ... Black Widow Spider Bit Me! Rashes: The Itchy Truth Contact Us Print Resources Send to a Friend ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...

  20. Big-hole drilling - the state of the art

    Lackey, M.D.


    The art of big-hole drilling has been in a continual state of evolution at the Nevada Test Site since the start of underground testing in 1961. Emplacement holes for nuclear devices are still being drilled by the rotary-drilling process, but almost all the hardware and systems have undergone many changes during the intervening years. The current design of bits, cutters, and other big-hole-drilling hardware results from contributions of manufacturers and Test Site personnel. The dual-string, air-lift, reverse-circulation system was developed at the Test Site. Necessity was really the Mother of this invention, but this circulation system is worthy of consideration under almost any condition. Drill rigs for big-hole drilling are usually adaptations of large oil-well drill rigs with minor modifications required to handle the big bits and drilling assemblies. Steel remains the favorite shaft lining material, but a lot of thought is being given to concrete linings, especially precast concrete.

  1. Mathematical Model and Simulation of a Pneumatic Apparatus for In-Drilling Alignment of an Inertial Navigation Unit during Horizontal Well Drilling

    Djurkov, Alexander; Cloutier, Justin; Mintchev, Martin P.


    Conventional methods in horizontal drilling processes incorporate magnetic surveying techniques for determining the position and orientation of the bottom-hole assembly (BHA). Such means result in an increased weight of the drilling assembly, higher cost due to the use of non-magnetic collars necessary for the shielding of the magnetometers, and significant errors in the position of the drilling bit. A fiber-optic gyroscope (FOG) based inertial navigation system (INS) has been pro...

  2. Drilling on Mars---Mathematical Model for Rotary-Ultrasonic Core Drilling of Brittle Materials

    Horne, Mera Fayez

    The results from the Phoenix mission led scientists to believe it is possible that primitive life exists below the Martian surface. Therefore, drilling in Martian soil in search for organisms is the next logical step. Drilling on Mars is a major engineering challenge due to the drilling depth requirement. Mars lacks a thick atmosphere and a continuous magnetic field that shield the planet's surface from solar radiation and solar flares. As a result, the Martian surface is sterile and if life ever existed, it must be found below the surface. In 2001, NASA's Mars Exploration Payload Advisory Group proposed that drilling should be considered as a priority investigation on Mars in an effort of finding evidence of extinct or extant life. On August 6, 2012, the team of engineers landed the spacecraft Curiosity on the surface of Mars by using a revolutionary hovering platform. The results from the Curiosity mission suggested the next logical step, which is drilling six meters deep in the red planet in search of life. Excavation tools deployed to Mars so far have been able to drill to a maximum depth of 6.5 cm. Thus, the drilling capabilities need to be increased by a factor or approximately 100 to achieve the goal of drilling six meters deep. This requirement puts a demand on developing a new and more effective technologies to reach this goal. Previous research shows evidence of a promising drilling mechanism in rotary-ultrasonic for what it offers in terms of high surface quality, faster rate of penetration and higher material removal rate. This research addresses the need to understand the mechanics of the drill bit tip and rock interface in rotary-ultrasonic drilling of brittle materials. A mathematical model identifying all contributing independent parameters, such as drill bit design parameters, drilling process parameters, ultrasonic wave amplitude and rocks' material properties, that have effect on rate of penetration is developed. Analytical and experimental

  3. Diamond heteroepitaxial lateral overgrowth

    Tang, Yung-Hsiu

    This dissertation describes improvements in the growth of single crystal diamond by microwave plasma-assisted chemical vapor deposition (CVD). Heteroepitaxial (001) diamond was grown on 1 cm. 2 a-plane sapphiresubstrates using an epitaxial (001) Ir thin-film as a buffer layer. Low-energy ion bombardment of the Ir layer, a process known as bias-enhanced nucleation, is a key step in achieving a high density of diamond nuclei. Bias conditions were optimized to form uniformly-high nucleation densities across the substrates, which led to well-coalesced diamond thin films after short growth times. Epitaxial lateral overgrowth (ELO) was used as a means of decreasing diamond internal stress by impeding the propagation of threading dislocations into the growing material. Its use in diamond growth requires adaptation to the aggressive chemical and thermal environment of the hydrogen plasma in a CVD reactor. Three ELO variants were developed. The most successful utilized a gold (Au) mask prepared by vacuum evaporation onto the surface of a thin heteroepitaxial diamond layer. The Au mask pattern, a series of parallel stripes on the micrometer scale, was produced by standard lift-off photolithography. When diamond overgrows the mask, dislocations are largely confined to the substrate. Differing degrees of confinement were studied by varying the stripe geometry and orientation. Significant improvement in diamond quality was found in the overgrown regions, as evidenced by reduction of the Raman scattering linewidth. The Au layer was found to remain intact during diamond overgrowth and did not chemically bond with the diamond surface. Besides impeding the propagation of threading dislocations, it was discovered that the thermally-induced stress in the CVD diamond was significantly reduced as a result of the ductile Au layer. Cracking and delamination of the diamond from the substrate was mostly eliminated. When diamond was grown to thicknesses above 0.1 mm it was found that

  4. String bit models for superstring

    Bergman, O.; Thorn, C.B.


    The authors extend the model of string as a polymer of string bits to the case of superstring. They mainly concentrate on type II-B superstring, with some discussion of the obstacles presented by not II-B superstring, together with possible strategies for surmounting them. As with previous work on bosonic string work within the light-cone gauge. The bit model possesses a good deal less symmetry than the continuous string theory. For one thing, the bit model is formulated as a Galilei invariant theory in (D {minus} 2) + 1 dimensional space-time. This means that Poincare invariance is reduced to the Galilei subgroup in D {minus} 2 space dimensions. Naturally the supersymmetry present in the bit model is likewise dramatically reduced. Continuous string can arise in the bit models with the formation of infinitely long polymers of string bits. Under the right circumstances (at the critical dimension) these polymers can behave as string moving in D dimensional space-time enjoying the full N = 2 Poincare supersymmetric dynamics of type II-B superstring.

  5. Optimizing drilling performance using a selected drilling fluid

    Judzis, Arnis [Salt Lake City, UT; Black, Alan D [Coral Springs, FL; Green, Sidney J [Salt Lake City, UT; Robertson, Homer A [West Jordan, UT; Bland, Ronald G [Houston, TX; Curry, David Alexander [The Woodlands, TX; Ledgerwood, III, Leroy W.


    To improve drilling performance, a drilling fluid is selected based on one or more criteria and to have at least one target characteristic. Drilling equipment is used to drill a wellbore, and the selected drilling fluid is provided into the wellbore during drilling with the drilling equipment. The at least one target characteristic of the drilling fluid includes an ability of the drilling fluid to penetrate into formation cuttings during drilling to weaken the formation cuttings.

  6. Diamond Synthesis Employing Nanoparticle Seeds

    Uppireddi, Kishore (Inventor); Morell, Gerardo (Inventor); Weiner, Brad R. (Inventor)


    Iron nanoparticles were employed to induce the synthesis of diamond on molybdenum, silicon, and quartz substrates. Diamond films were grown using conventional conditions for diamond synthesis by hot filament chemical vapor deposition, except that dispersed iron oxide nanoparticles replaced the seeding. This approach to diamond induction can be combined with dip pen nanolithography for the selective deposition of diamond and diamond patterning while avoiding surface damage associated to diamond-seeding methods.

  7. Bits and q-bits as versatility measures

    José R.C. Piqueira


    Full Text Available Using Shannon information theory is a common strategy to measure any kind of variability in a signal or phenomenon. Some methods were developed to adapt information entropy measures to bird song data trying to emphasize its versatility aspect. This classical approach, using the concept of bit, produces interesting results. Now, the original idea developed in this paper is to use the quantum information theory and the quantum bit (q-bit concept in order to provide a more complete vision of the experimental results.Usar a teoria da informação de Shannon é uma estratégia comum para medir todo tipo de variabilidade em um sinal ou fenômeno. Alguns métodos foram desenvolvidos para adaptar a medida de entropia informacional a dados de cantos de pássaro, tentando enfatizar seus aspectos de versatilidade. Essa abordagem clássica, usando o conceito de bit, produz resultados interessantes. Agora, a idéia original desenvolvida neste artigo é usar a teoria quântica da informação e o conceito de q-bit, com a finalidade de proporcionar uma visão mais completa dos resultados experimentais.

  8. A Novel Image Data Hiding Scheme with Diamond Encoding

    Wu Hsien-Chu


    Full Text Available A novel data hiding scheme in digital images with the diamond encoding by pixel value adjustment is proposed. The proposed method is the extension of the exploiting modification direction (EMD embedding scheme. First, the process of embedding partitions the cover image into nonoverlapping blocks of two consecutive pixels and transforms the secret messages to a series of -ary digits. For each block, the diamond encoding technique is applied to calculate the diamond characteristic value, and one secret -ary digit is concealed into the diamond characteristic value. The diamond characteristic value is modified to secret digit and it can be obtained by adjusting pixel values in a block. This scheme is designed in such a way that the distortion of each block after diamond encoding is never out of the embedding parameter , and the block capacity is equal to . The diamond encoding provides an easy way to produce a more perceptible result than those yielded by simple least-significant-bit substitution methods. The embedded secret data can be extracted without the original cover image. Experimental results have demonstrated that the proposed method is capable of hiding more secret data while keeping the stego-image quality degradation imperceptible.

  9. Effects of hydraulic parameter cleaning variations on rate of penetration of soft formation insert bits

    Doiron, H.H.; Deane, J.D.


    Effects of hydraulic cleaning parameter variations on rate of penetration response of 7 7/8 inch diameter soft formation insert bits have been measured in laboratory drilling tests. Tests were conducted in Mancos Shale rock samples at 700 psi and 4000 psi simulated overbalance pressure conditions using a 9.1 pound per gallon bentonite-barite water base drilling fluid. Bit hydraulic horsepower was varied from 0.72 to 9.5 HHP/in/sup 2/ using two or three nozzles in sizes ranging from 9/32 to 14/32 inches in diameter. Some improvements in ROP at constant bit hydraulic horsepower and impact force levels were obtained with two nozzle configurations vs. three nozzle configurations, but improvements were not consistently out of the range of normal test to test variations. Reduction in drilling costs due to the measured response of ROP to improved hydraulic cleaning is compared to increased operating costs required to provide additional hydraulics. Results indicate that bit hydraulic horsepower levels in excess of popular rules of thumb are cost effective in slow drilling due to high overbalance pressure.

  10. Application of SJ75 Wire-line Coring Drilling Tools in Western Henan Coalfield Drilling%SJ75绳索取心钻具在豫西地区煤田钻探中的应用



    豫西地区岩层倾角大,岩石软硬互层较多,特别是金斗山砂岩、平顶山砂岩,可钻性级别高,裂隙发育,地层破碎,掉块、漏水,钻孔易斜,造成孔内事故增多甚至钻孔报废,钻探施工效率低。针对该区地层特点,采用SJ75绳索取心钻具进行钻探施工,首先,对其配套设备进行了改进,将4135G型柴油机皮带轮由Φ350 mm加大至Φ396mm,以提高立轴的转速;在立根箱里面垫上了一层厚30 mm左右的木板,木板上面又垫了一层厚15 mm的橡胶皮,以有效地保护丝扣。其次,在钻进过程中,先后对平底、齿形、复合片钻头进行试验。试验表明,齿形钻头是比较适合该地区绳索取心钻进的金刚石钻头。再次,结合绳索也取心对钻井液的要求,应用非分散低固相、无固相和堵漏低固相钻井液对不同地层进行钻进。各种措施的采取,很好地解决了钻进中遇到的问题,减少了孔内事故,提高了钻孔质量。%The strata in western Henan have characteristics of large dip angle, frequent alternating soft and hard beds, especially the Jindoushan sandstone and Pingdingshan sandstone have higher drillability level with developed fissures, fragmentation of rock, easy to off the blocks, current loss and deviation, thus caused increasing of drilling accidents even to discard, low drilling efficiency. In allu⁃sion to strata characteristics in the area, the SJ75 wire-line coring drilling tools have been used. Firstly, improved associated facilities, enlarged 4135G diesel engine belt pulley fromΦ350mm toΦ396mm to increase vertical shaft rotation rate;a layer of wood board about 30mm thick filled up on the pipe rack, than a 15mm thick layer of rubber on wood board to protect screw thread effectively. Secondly, during the drilling process, has tested the flat bottom, jagged and PDC bits successively. The test has shown that the jagged diamond bit is rather

  11. Remoção de braquetes cerâmicos com alicate de How associado à broca diamantada: avaliação da topografia do esmalte Removal of ceramic brackets with How-type pliers in association with diamond drill: a topographic evaluation of the enamel

    Matheus Melo Pithon


    Full Text Available OBJETIVO: avaliar a topografia do esmalte dentário após a descolagem de braquetes cerâmicos Allure (GAC/Dentsply através de dois diferentes métodos. METODOLOGIA: foram utilizados 20 incisivos inferiores permanentes bovinos divididos em dois grupos (n = 10. Em ambos os grupos foram feitas colagens de braquetes cerâmicos Allure utilizando-se Concise (3M Unitek seguindo as recomendações do fabricante. Após a colagem, os espécimes foram mantidos em estufa, a 37°C por 24 horas, para completa polimerização do compósito. Após isso foi realizada a remoção dos braquetes, sendo que no grupo A foi utilizado alicate de corte de amarrilho e no grupo B alicate tipo How em braquete previamente fragilizado com broca diamantada. Em ambos os grupos o remanescente de compósito foi removido com broca de carboneto de tungstênio. Após descolagem, os espécimes foram preparados para análise em microscopia eletrônica de varredura, para posterior análise da superfície do esmalte. RESULTADOS E CONCLUSÕES: os resultados mostraram maior quantidade de arranhões nos dentes do grupo A, esses resultados foram estatisticamente superiores ao grupo B com p OBJECTIVE: to evaluate the topography of the tooth enamel after debonding Allure ceramic brackets using two different methods. METHODS: Twenty bovine permanent lower incisors were divided into two groups (n = 10. In groups A and B Allure ceramic brackets were bonded to the teeth using Concise composite according to manufacture’s recommendations. After the bonding procedures, the samples were kept in stove at 37ºC for 24 hours for complete composite polymerization. Next, the brackets of group A were removed by using wire pliers, whereas the brackets of group B, which had been previously weakened with diamond drill, were debonded by using How-type pliers. In both groups the composite remnant was removed by using a tungsten carbide-tipped drill. Following the debonding procedures, the samples were

  12. Tesco's Bob Tessari: launching a drilling revolution

    Budd, G.


    The 'Casing Drilling' technology, patented by Tesco, which allows operators to simultaneously drill, case and evaluate oil and gas wells, is described. The system is claimed to substantially reduce the amount of lost circulation, loss of well control and bore hole instability problems that have been documented to account for about 25 per cent of total rig time on a well, and at least $4 billion (or 10 per cent of the $40 billion annual global drilling tab) spent on 'unscheduled events' associated with tripping drill pipe. With the Casing Drilling process, wells are drilled using standard oilfield casing instead of drill pipe. The host of downhole problems associated with tripping in and out of the hole are avoided, as the casing pipe is never removed. Instead, drill bits and other downhole tools are tripped through the casing with wireline at a rate of about 500 ft per minute, drastically reducing tripping time. Tesco also developed the portable top drive, the manufacture and rental of which constitutes a large part of the company's business, besides helping technologically to make Casing Drilling possible. Much of the company's success is attributed to the tenacity and zest for innovative approaches of the company's CEO, Bob Tessari, who is largely responsible for the company finding itself at the centre of a drilling technology revolution.

  13. Advanced Seismic While Drilling System

    Robert Radtke; John Fontenot; David Glowka; Robert Stokes; Jeffery Sutherland; Ron Evans; Jim Musser


    A breakthrough has been discovered for controlling seismic sources to generate selectable low frequencies. Conventional seismic sources, including sparkers, rotary mechanical, hydraulic, air guns, and explosives, by their very nature produce high-frequencies. This is counter to the need for long signal transmission through rock. The patent pending SeismicPULSER{trademark} methodology has been developed for controlling otherwise high-frequency seismic sources to generate selectable low-frequency peak spectra applicable to many seismic applications. Specifically, we have demonstrated the application of a low-frequency sparker source which can be incorporated into a drill bit for Drill Bit Seismic While Drilling (SWD). To create the methodology of a controllable low-frequency sparker seismic source, it was necessary to learn how to maximize sparker efficiencies to couple to, and transmit through, rock with the study of sparker designs and mechanisms for (a) coupling the sparker-generated gas bubble expansion and contraction to the rock, (b) the effects of fluid properties and dynamics, (c) linear and non-linear acoustics, and (d) imparted force directionality. After extensive seismic modeling, the design of high-efficiency sparkers, laboratory high frequency sparker testing, and field tests were performed at the University of Texas Devine seismic test site. The conclusion of the field test was that extremely high power levels would be required to have the range required for deep, 15,000+ ft, high-temperature, high-pressure (HTHP) wells. Thereafter, more modeling and laboratory testing led to the discovery of a method to control a sparker that could generate low frequencies required for deep wells. The low frequency sparker was successfully tested at the Department of Energy Rocky Mountain Oilfield Test Center (DOE RMOTC) field test site in Casper, Wyoming. An 8-in diameter by 26-ft long SeismicPULSER{trademark} drill string tool was designed and manufactured by TII

  14. Optimizing Geothermal Drilling: Oil and Gas Technology Transfer

    Denninger, Kate; Eustes, Alfred; Visser, Charles; Baker, Walt; Bolton, Dan; Bell, Jason; Bell, Sean; Jacobs, Amelia; Nagandran, Uneshddarann; Tilley, Mitch; Quick, Ralph


    There is a significant amount of financial risk associated with geothermal drilling. This study of drilling operations seeks opportunities to improve upon current practices and technologies. The scope of this study included analyzing 21 geothermal wells and 21 oil and gas wells. The goal was to determine a 'Perfect Well' using historical data to compare the best oil and gas well to the best geothermal well. Unfortunately, limitations encountered in the study included missing data (bit records, mud information, etc.) and poor data collection practices An online software database was used to format drilling data to IADC coded daily drilling reports and generate figures for analysis. Six major issues have been found in geothermal drilling operations. These problems include lost circulation, rig/ equipment selection, cementing, penetration rate, drilling program, and time management. As a result of these issues, geothermal drilling averaged 56.4 days longer than drilling comparable oil and gas wells in the wells in this study. Roughly $13.9 million was spent on non-productive time in the 21 geothermal wells, compared with only $1.3 million in the oil and gas wells, assuming a cost of $50,000 per day. Comparable events such as drilling the same sized hole, tripping in/out, cementing, and running the same size casing took substantially less time in the oil and gas wells. Geothermal wells were drilled using older and/or less advanced technology to depths less than 10,000 feet, while oil and gas wells reached 12,500 feet faster with purpose built rigs. A new approach is now underway that will optimize drilling programs throughout the drilling industry using Mechanical Specific Energy (MSE) as a tool to realize efficient drilling processes. Potential improvements for current geothermal operations are: the use of electronic records, real time services, and official glossary terms to describe rig operations, and advanced drilling rigs/technology.

  15. A Holistic Approach to Bit Preservation

    Zierau, Eld Maj-Britt Olmütz


    This thesis presents three main results for a holistic approach to bit preservation, where the ultimate goal is to find the optimal bit preservation strategy for specific digital material that must be digitally preserved. Digital material consists of sequences of bits, where a bit is a binary dig...


    Nediljka Gaurina-Međimurec


    Casing drilling is an alternative option to conventional drilling and uses standard oilfield casing instead of drillstring. This technology is one of the greatest developments in drilling operations. Casing drilling involves drilling and casing a well simultaneously. In casing driling process, downhole tools can be retrieved, through the casing on wire-line, meaning tool recovery or replacement of tools can take minutes versus hours under conventional methods. This process employs wireline-re...

  17. Nano-inclusions in diamond: Evidence of diamond genesis

    Wirth, R.


    The use of Focused Ion Beam technology (FIB) for TEM sample preparation introduced approximately 15 years ago revolutionized the application of TEM in Geosciences. For the first time, FIB enabled cutting samples for TEM use from exactly the location we are interested in. Applied to diamond investigation, this technique revealed the presence of nanometre-sized inclusions in diamond that have been simply unknown before. Nanoinclusions in diamond from different location and origin such as diamonds from the Lower and Upper Mantle, metamorphic diamonds (Kazakhstan, Erzgebirge, Bohemia), diamonds from ophiolites (Tibet, Mongolia, Xinjiang, Ural Mountains), diamonds from igneous rocks (Hawaii, Kamchatka) and impact diamonds (Popigai Crater, Siberia) have been investigated during the last 15 years. The major conclusion of all these TEM studies is, that the nanoinclusions, their phases and phase composition together with the micro- and nanostructure evidence the origin of diamond and genesis of diamond. We can discriminate Five different mechanisms of diamond genesis in nature are observed: Diamond crystallized from a high-density fluid (Upper mantle and metamorphic diamond). Diamond crystallized from carbonatitic melt (Lower mantle diamond). Diamond precipitates from a metal alloy melt (Diamond from ophiolites). Diamond crystallized by gas phase condensation or chemical vapour condensation (CVD) (Lavas from Kamchatka, xenoliths in Hawaiian lavas). Direct transformation of graphite into diamond.

  18. Chuanshi Brand Tri-cone Roller Bit

    Chen Xilong; Shen Zhenzhong; Yuan Xiaoyi


    @@ Compared with other types of bits, the tri-cone roller bit has the advantages of excellent comprehensive performance, low price, wide usage range. It is free of formation limits. The tri-cone roller bit accounts for 90% of the total bits in use. The Chengdu Mechanical Works, as a major manufacturer of petroleum mechanical products and one of the four major tri-cone roller bit factories in China,has produced 120 types of bits in seven series and 19 sizes since 1967. The bits manufactured by the factory are not only sold to the domestic oilfields, but also exported to Japan, Thailand, Indonesia, the Philippines and the Middle East.

  19. Rotary ultrasonic bone drilling: Improved pullout strength and reduced damage.

    Gupta, Vishal; Pandey, Pulak M; Silberschmidt, Vadim V


    Bone drilling is one of the most common operations used to repair fractured parts of bones. During a bone drilling process, microcracks are generated on the inner surface of the drilled holes that can detrimentally affect osteosynthesis and healing. This study focuses on the investigation of microcracks and pullout strength of cortical-bone screws in drilled holes. It compares conventional surgical bone drilling (CSBD) with rotary ultrasonic bone drilling (RUBD), a novel approach employing ultrasonic vibration with a diamond-coated hollow tool. Both techniques were used to drill holes in porcine bones in an in-vitro study. Scanning electron microscopy was used to observe microcracks and surface morphology. The results obtained showed a significant decrease in the number and dimensions of microcracks generated on the inner surface of drilled holes with the RUBD process in comparison to CSBD. It was also observed that a higher rotational speed and a lower feed rate resulted in lower damage, i.e. fewer microcracks. Biomechanical axial pullout strength of a cortical bone screw inserted into a hole drilled with RUBD was found to be much higher (55-385%) than that for CSBD.

  20. Parameter definition using vibration prediction software leads to significant drilling performance improvements

    Amorim, Dalmo; Hanley, Chris Hanley; Fonseca, Isaac; Santos, Juliana [National Oilwell Varco, Houston TX (United States); Leite, Daltro J.; Borella, Augusto; Gozzi, Danilo [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)


    The understanding and mitigation of downhole vibration has been a heavily researched subject in the oil industry as it results in more expensive drilling operations, as vibrations significantly diminish the amount of effective drilling energy available to the bit and generate forces that can push the bit or the Bottom Hole Assembly (BHA) off its concentric axis of rotation, producing high magnitude impacts with the borehole wall. In order to drill ahead, a sufficient amount of energy must be supplied by the rig to overcome the resistance of the drilling system, including the reactive torque of the system, drag forces, fluid pressure losses and energy dissipated by downhole vibrations, then providing the bit with the energy required to fail the rock. If the drill string enters resonant modes of vibration, not only does it decreases the amount of available energy to drill, but increases the potential for catastrophic downhole equipment and drilling bit failures. In this sense, the mitigation of downhole vibrations will result in faster, smoother, and cheaper drilling operations. A software tool using Finite Element Analysis (FEA) has been developed to provide better understanding of downhole vibration phenomena in drilling environments. The software tool calculates the response of the drilling system at various input conditions, based on the design of the wellbore along with the geometry of the Bottom Hole Assembly (BHA) and the drill string. It identifies where undesired levels of resonant vibration will be driven by certain combinations of specific drilling parameters, and also which combinations of drilling parameters will result in lower levels of vibration, so the least shocks, the highest penetration rate and the lowest cost per foot can be achieved. With the growing performance of personal computers, complex software systems modeling the drilling vibrations using FEA has been accessible to a wider audience of field users, further complimenting with real time

  1. Putting a damper on drilling's bad vibrations

    Jardine, S. (Sedco forex, Montrouge (France)); Malone, D. (Anadrill, Sugar Land, TX (United States)); Sheppard, M. (Schlumberger Cambridge Research, Cambridge (United Kingdom))


    Harmful drilling vibrations are costing the industry dearly. Three main vibration types (axial, torsional and transverse) are explained and its causes discussed. Technology exists to eliminate most vibrations, but requires more systematic deployment than is usual. Hardware that eliminates vibrations is reviewed, including downhole shock measurement, torque feedback shock guards and antiwhirl bits. 9 figs., 11 refs.

  2. Diamond tool machining of materials which react with diamond

    Lundin, Ralph L.; Stewart, Delbert D.; Evans, Christopher J.


    Apparatus for the diamond machining of materials which detrimentally react with diamond cutting tools in which the cutting tool and the workpiece are chilled to very low temperatures. This chilling halts or retards the chemical reaction between the workpiece and the diamond cutting tool so that wear rates of the diamond tool on previously detrimental materials are comparable with the diamond turning of materials which do not react with diamond.

  3. Design of Telerobotic Drilling Control System with Haptic Feedback

    Faraz Shah


    system with haptic feedback that allows for the remote control of the vertical drilling operation. The human operator controls the vertical penetration velocity using a haptic device while simultaneously receiving the haptic feedback from the locally implemented virtual environment. The virtual environment is rendered as a virtual spring with stiffness updated based on the estimate of the stiffness of the rock currently being cut. Based on the existing mathematical models of drill string/drive systems and rock cutting/penetration process, a robust servo controller is designed which guarantees the tracking of the reference vertical penetration velocity of the drill bit. A scheme for on-line estimation of the rock intrinsic specific energy is implemented. Simulations of the proposed control and parameter estimation algorithms have been conducted; consequently, the overall telerobotic drilling system with a human operator controlling the process using PHANTOM Omni haptic device is tested experimentally, where the drilling process is simulated in real time in virtual environment.

  4. Ellog Auger Drilling -"3-in-one" method for hydrogeological data collection

    Sørensen, Kurt; Larsen, Flemming


    continuously while drilling. Data processing is carried out in the field, and recorded log features are displayed as drilling advances. A slotted section in the stem, above the cutting head, allows anaerobic water and soil-gas samples to be taken at depth intervals of approximately 0.2 m. The logging, water......The Ellog auger drilling method is an integrated approach for hydrogeological data collection during auger drilling in unconsolidated sediments. The drill stem is a continuous flight, hollow-stem auger with integrated electrical and gamma logging tools. The geophysical logging is performed......, and gas sampling instrumentation in the drill stem is removable; therefore, when the drill stem is pulled back, piezometers can be installed through the hollow stem. Cores of sediments can subsequently be taken continuously using a technique in which the drill bit can be reinserted after each coring...

  5. Investigation of noise levels generated by otologic drills.

    Dalchow, Carsten V; Hagemeier, K C; Muenscher, A; Knecht, R; Kameier, F


    Drilling during temporal bone surgery may result in temporary or permanent noise-induced hearing loss or tinnitus. This has practical implications for both the patient and the surgeon. Different surgical drill devices, routinely used in temporal bone surgery, are examined referring to their emitted sound levels and sound transport. Two surgical drills were used on a brass tubing and a steel wire to simulate sound generation during temporal bone surgery. Overview measurements were performed on human cadaver in a medical laboratory. A set-up in a silent chamber was chosen to exclude external sound sources. The noise emissions and the vibration generated by a silver diamond bur and a cutting drill (Rose bur) were registered when used on a brass tubing and a solid steel wire with sound level meter and a non-contact laser vibrometer. The highest sound rate generated by the diamond burr did not exceed 63 dB(A) when used on a solid steel wire, whereas the cutting burr emitted 76 dB(A). Both drills produced lower sound levels on the brass tubing. Again the cutting burr topped the diamond burr with 68 dB(A) against 56 dB(A). The sound emission did not exceed 76 dB(A) outside a radius 4 cm around the drill location. In conclusion, sound emission generated by different surgical burs routinely used in temporal bone surgery is lower than expected. Still, within a small radius around those burs high sound pressure levels may be induced into surrounding structures such as ossicles, labyrinth, and cochlear. Still damage is feasible when using surgical drills for a longer time period close to sensitive structures.

  6. Coated carbide drill performance under soluble coconut oil lubricant and nanoparticle enhanced MQL in drilling AISI P20

    Jamil, N. A. M.; Azmi, A. I.; Fairuz, M. A.


    This research experimentally investigates the performance of a TiAlN coated carbide drill bit in drilling AISI P20 through two different kinds of lubricants, namely; soluble coconut oil (SCO) and nanoparticle-enhanced coconut oil (NECO) under minimum quantity lubrication system. The tool life and tool wear mechanism were studied using various cutting speeds of 50, 100 and 150 m/min with a constant feed of 0.01 mm/rev. Since the flank wear land was not regular along the cutting edge, the average flank wear (VB) was measured at several points using image analysis software. The drills were inspected using a scanning electron microscope to further elucidate the wear mechanism. The result indicates that drilling with the nanoparticle- enhanced lubricant was better in resisting the wear and improving the drill life to some extent

  7. Optical engineering of diamond

    Rabeau, James R


    This is the first comprehensive book on the engineering of diamond optical devices. It will give readers an up-to-date account of the properties of optical quality synthetic diamond (single crystal, nanodiamond and polycrystalline) and reviews the large and growing field of engineering of diamond-based optical devices, with applications in quantum computation, nano-imaging, high performance lasers, and biomedicine. It aims to provide scientists, engineers and physicists with a valuable resource and reference book for the design and performance of diamond-based optical devices.

  8. Research and development of improved cavitating jets for deep-hole drilling

    Johnson, V.E. Jr.; Lindenmuth, W.T.; Chahine, G.L.; Conn, A.F.; Frederick, G.S.


    Improved cavitating nozzles have been developed as part of an on-going program to increase the rate of penetration of deep-hole drill bits. Based on the four criteria of: incipient cavitation number, amplitude of pressure fluctuation (and hence enhanced structuring of the jet flow), rock cutting, and cleaning chips from the hole bottom - these new, STRATOJET (STRuctured Acoustically Tuned Oscillating JET) cavitating nozzle systems have out-performed both conventional drill bit nozzles and the basic CAVIJET cavitating jets. Although nozzle designs which provide large amplitude pressure modulations are now available for the operation in water, additional research is needed to optimize self-resonating jets for use: (a) in mud, (b) in specific drill bit designs, and (c) at higher system pressures than now currently used for deep-hole drilling.

  9. Torsional vibrations of helically buckled drill-strings: experiments and FE modelling

    Kapitaniak, M.; Hamaneh, V. V.; Wiercigroch, M.


    This paper presents investigations of a complex drill-string vibrations on a novel experimental rig, developed by the Centre for Applied Dynamics Research at the University of Aberdeen. The rig is capable of exhibiting of all major types of drill-string vibrations, including torsional, axial and lateral modes. The importance of this work lies in the fact, that the experimental rig utilizes real industrial drill-bits and rock samples, which after careful identification of Torque On Bit (TOB) speed curves, allows to use an equivalent friction model to accommodate for both frictional and cutting components of the bit-rock interactions. Moreover, the proposed Finite Element model, after a careful calibration, is capable of replicating experimental results, for the prebuckled configuration of the drill-string. This allows us to observe the effect of winding and unwinding of the helical deformation during stick-slip motion.

  10. Robotic Planetary Drill Tests

    Glass, Brian J.; Thompson, S.; Paulsen, G.


    Several proposed or planned planetary science missions to Mars and other Solar System bodies over the next decade require subsurface access by drilling. This paper discusses the problems of remote robotic drilling, an automation and control architecture based loosely on observed human behaviors in drilling on Earth, and an overview of robotic drilling field test results using this architecture since 2005. Both rotary-drag and rotary-percussive drills are targeted. A hybrid diagnostic approach incorporates heuristics, model-based reasoning and vibration monitoring with neural nets. Ongoing work leads to flight-ready drilling software.

  11. Study of concrete drilling for automated non-destructive evaluation and rehabilitation system for bridge decks

    Trkov, Mitja; Liu, Fei; Yi, Jingang; Baruh, Haim


    Robotic drilling is the basic process for the non-destructive rehabilitation (NDR) system in the Automated Non-destructive Evaluation and Rehabilitation System (ANDERS) for bridge decks. In this paper, we present a study and testing of a concrete drilling process that is used for robotic drilling process for bridge decks repair. We first review the ANDERS and NDR design. Then we present the experimental setup for the drilling process study. A set of testing experiments are performed considering drilling process parameters such as drill bit size, drill rotating speed, drill thrust force and types of concrete composites. Based on the experiments and analysis, we identify and find that the optimal set of drilling process parameters for the ANDERS application is 1/4-inch bit size, drill rotational speed of 1500 rpm and thrust force around 35 lbs. We also demonstrate that the monitoring of drill feeding displacement and thrust force cannot be used to detect and identify the cracks in bridge decks.

  12. Le dépôt de diamant en couche mince et ses applications Thin-Layer Diamond Depositing and Its Applications

    Bertrand A.


    Full Text Available Nous avons cherché à faire le point sur la fabrication de couches minces de diamant qui, après avoir été très étudiée aux États-Unis vers la fin des années 1950, a fait l'objet d'une percée technologique soviétique en 1977. Celle-ci utilise l'effet solvant de l'hydrogène mélangé à un peu de méthane. Transformé en hydrogène atomique par décharge électrique, il interdit le dépôt de graphite et par conséquent permet seulement celui du diamant. Ce résultat est riche d'applications prometteuses en mécanique, en optique, en électronique. . . et constitue un élément clé pour la recherche spatiale. Les Japonais ont mis cinq ans pour réagir et les Américains cinq autres années. Mais ces derniers espèrent refaire leur retard grâce au programme Diamond Technology Initiative établi dans le cadre de l'initiative de Défense Stratégique (Guerre des Étoiles. Les retombées de ces travaux devraient concerner l'industrie pétrolière (paliers, trépans, capteurs en milieu extrême. This article reviews the depositing of diamond thin layers. After much research had been done on this technique in the United States in the late 1950s, a technological breakthrough was made by the Soviets in 1977. This breakthrough uses the solventeffect of hydrogen mixed with a bit of methane. This is transformed into atomic hydrogen by an electric discharge, thus preventing graphite from being deposited and hence enabling only diamond to be deposited. This achievement has a wealth of promising applications in mechanics, optics, electronics, etc. It is also a key element for space research. The Japanese took five years to react and the Americans another five years. But these latter hope to make up for lost time with the Diamond Technology Initiativepromoted within the framework of the Strategic Defense Initiative ( star wars . The fallouts from this research should involve the petroleum industry (bearings, drill bits, sensors in extreme

  13. The Hans Tausen drill

    Johnsen, Sigfus Johann; Dahl-Jensen, Dorthe; Steffensen, Jørgen Peder


    In the mid-1990s, excellent results from the GRIP and GISP2 deep drilling projects in Greenland opened up funding for continued ice-coring efforts in Antarctica (EPICA) and Greenland (NorthGRIP). The Glaciology Group of the Niels Bohr Institute, University of Copenhagen, was assigned the task...... of providing drilling capability for these projects, as it had done for the GRIP project. The group decided to further simplify existing deep drill designs for better reliability and ease of handling. The drill design decided upon was successfully tested on Hans Tausen Ice Cap, Peary Land, Greenland, in 1995....... The 5.0 m long Hans Tausen (HT) drill was a prototype for the ~11 m long EPICA and NorthGRIP versions of the drill which were mechanically identical to the HT drill except for a much longer core barrel and chips chamber. These drills could deliver up to 4 m long ice cores after some design improvements...

  14. Experimental study of surface quality and damage when drilling unidirectional CFRP composites

    Eshetu D. Eneyew


    Full Text Available In this study, an experimental investigation on the drilling of unidirectional carbon fiber reinforced plastic (UD-CFRP composite was conducted using polycrystalline diamond (PCD tipped eight facet drill. The quality of the drilled hole surface was examined through surface roughness measurements and surface damage by scanning electron microscopy (SEM. It was found that fiber pullout occurred in two specific sectors relative to the angle between the cutting direction and the fiber orientation. The thrust force was highly influenced by the feed rate than the cutting speed and it shows a significant variation throughout the rotation of the drill.

  15. Diamond films: Historical perspective

    Messier, R. [Pennsylvania State Univ., University Park (United States)


    This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

  16. Investing in Diamonds

    Renneboog, Luc


    This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD

  17. Investing in Diamonds

    Renneboog, Luc


    This paper examines the risk-return characteristics of investment grade gems (white diamonds, colored diamonds and other types of gems including sapphires, rubies, and emeralds). The transactions are coming from gem auctions and span the period 1999-2012. Over our time frame, the annual nominal USD

  18. Joint Rescue Drill


    Ships gather for a joint rescue drill at the Waigaoqiao Dock in Shanghai on August 24.A large-scale rescue drill, combining maritime and air forces,was held as part of the ongoing World Maritime Rescue Conference 2011 in the city.During the drill,

  19. Towards High Density 3-D Memory in Diamond

    Henshaw, Jacob; Dhomkar, Siddharth; Meriles, Carlos; Jayakumar, Harishankar

    The nitrogen-vacancy (NV) center in diamond is presently the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Of great utility is the ability to optically initialize the NV charge state, which has an immediate impact on the center's light emission properties. Here, we use two-color microscopy in NV-rich, type-1b diamond to demonstrate fluorescence-encoded long-term storage of classical information. As a proof of principle, we write, reset, and rewrite various patterns with 2-D binary bit density comparable to present DVD-ROM technology. The strong fluorescence signal originating from the diffraction-limited bit volume allows us to transition from binary to multi-valued encoding, which translates into a significant storage capacity boost. Finally, we show that our technique preserves information written on different planes of the diamond crystal and thus serves as a platform for three-dimensional storage. Substantial enhancement in the bit density could be achieved with the aid of super resolution microscopy techniques already employed to discriminate between NVs with sub-diffraction, nanometer accuracy, a regime where the storage capacity could exceed 1017 bytes/cm3 We acknowledge support from the National Science Foundation through Grant NSF-1314205.


    Yury Gutsalenko


    Full Text Available The paper generalizes on the one hand theory of kinematic-geometrical simulation of grinding processes by means of tools with working part as binding matrix with abrasive grains located in it in random manner, for example diamond grains, and on the other hand practical performance of combined grinding process, based on introduction of additional energy as electric discharges and called by the organization-developer (Kharkov Polytechnic Institute «diamond-spark grinding» as applied to processing by means of diamond wheel. Implementation of diamond-spark grinding technologies on the basis of developed generalized theoretical approach allows to use the tool with prescribed tool-life, moreover to make the most efficient use of it up to full exhausting of tool-life, determined by diamond-bearing thickness. Development is directed forward computer-aided manufacturing.

  1. Diamond Integrated Optomechanical Circuits

    Rath, Patrik; Nebel, Christoph; Wild, Christoph; Pernice, Wolfram H P


    Diamond offers unique material advantages for the realization of micro- and nanomechanical resonators due to its high Young's modulus, compatibility with harsh environments and superior thermal properties. At the same time, the wide electronic bandgap of 5.45eV makes diamond a suitable material for integrated optics because of broadband transparency and the absence of free-carrier absorption commonly encountered in silicon photonics. Here we take advantage of both to engineer full-scale optomechanical circuits in diamond thin films. We show that polycrystalline diamond films fabricated by chemical vapour deposition provide a convenient waferscale substrate for the realization of high quality nanophotonic devices. Using free-standing nanomechanical resonators embedded in on-chip Mach-Zehnder interferometers, we demonstrate efficient optomechanical transduction via gradient optical forces. Fabricated diamond resonators reproducibly show high mechanical quality factors up to 11,200. Our low cost, wideband, carri...

  2. Reaching 1 m deep on Mars: the Icebreaker drill.

    Zacny, K; Paulsen, G; McKay, C P; Glass, B; Davé, A; Davila, A F; Marinova, M; Mellerowicz, B; Heldmann, J; Stoker, C; Cabrol, N; Hedlund, M; Craft, J


    The future exploration of Mars will require access to the subsurface, along with acquisition of samples for scientific analysis and ground-truthing of water ice and mineral reserves for in situ resource utilization. The Icebreaker drill is an integral part of the Icebreaker mission concept to search for life in ice-rich regions on Mars. Since the mission targets Mars Special Regions as defined by the Committee on Space Research (COSPAR), the drill has to meet the appropriate cleanliness standards as requested by NASA's Planetary Protection Office. In addition, the Icebreaker mission carries life-detection instruments; and in turn, the drill and sample delivery system have to meet stringent contamination requirements to prevent false positives. This paper reports on the development and testing of the Icebreaker drill, a 1 m class rotary-percussive drill and triple redundant sample delivery system. The drill acquires subsurface samples in short, approximately 10 cm bites, which makes the sampling system robust and prevents thawing and phase changes in the target materials. Autonomous drilling, sample acquisition, and sample transfer have been successfully demonstrated in Mars analog environments in the Arctic and the Antarctic Dry Valleys, as well as in a Mars environmental chamber. In all environments, the drill has been shown to perform at the "1-1-100-100" level; that is, it drilled to 1 m depth in approximately 1 hour with less than 100 N weight on bit and approximately 100 W of power. The drilled substrate varied and included pure ice, ice-rich regolith with and without rocks and with and without 2% perchlorate, and whole rocks. The drill is currently at a Technology Readiness Level (TRL) of 5. The next-generation Icebreaker drill weighs 10 kg, which is representative of the flightlike model at TRL 5/6.

  3. Surface graphitization analysis of cerium-polished HFCVD diamond films with micro-raman spectra

    WANG Shubin; SUN Yujing; TIAN Shi


    The etching technique using Ce is a convenient and fast method for polishing and shaping diamond films. In this study, the influence of polishing parameters such as polishing temperature and time on the surface crystallinity and phase composition of diamond films was thoroughly investigated via the analysis of Raman spectra such as FWHM and ID/IG. Moreover, the issue on the graphitization of diamond after polishing with Ce was further researched through the detailed study of the depth distribution of Raman data including FWHM and ID/IG, and a result completely different from the hot-iron metal polished ones was obtained. The results showed that polished diamond films had considerably higher diamond content than those before polishing, and not a bit of graphitization was found in the polished ones, owing to a higher solubility of carbon in rare earth metal Ce than that in transition metals, and the original crystallinity of the films polished with Ce did not deteriorate.

  4. Flexible Bit Preservation on a National Basis

    Jurik, Bolette; Nielsen, Anders Bo; Zierau, Eld


    In this paper we present the results from The Danish National Bit Repository project. The project aim was establishment of a system that can offer flexible and sustainable bit preservation solutions to Danish cultural heritage institutions. Here the bit preservation solutions must include support...... of bit safety as well as other requirements like e.g. confidentiality and availability. The Danish National Bit Repository is motivated by the need to investigate and handle bit preservation for digital cultural heritage. Digital preservation relies on the integrity of the bits which digital material...... consists of, and it is with this focus that the project was initiated. This paper summarizes the requirements for a general system to offer bit preservation to cultural heritage institutions. On this basis the paper describes the resulting flexible system which can support such requirements. The paper...

  5. Ionoluminescence of diamond, synthetic diamond and simulants

    Calvo del Castillo, H. [Departamento de Geologia y Geoquimica, Facultad de Ciencias, Universidad Autonoma de Madrid, Ctra de Colmenar km 15, Madrid 27049 (Spain); Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Ruvalcaba-Sil, J.L. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Barboza-Flores, M. [Centro de Investigacio en Fisica, Universidad de Sonora, Apartado postal 5-088, Hermosillo, Sonora 83190 (Mexico); Belmont, E. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, Ciudad de Mexico 04519, Mexico, DF (Mexico); Calderon, T. [Departamento de Geologia y Geoquimica, Facultad de Ciencias, Universidad Autonoma de Madrid, Ctra de Colmenar km 15, Madrid 27049 (Spain)], E-mail:


    Ionoluminescence (IL) spectra of diamond (natural samples and synthetic CVD) and its more common synthetic simulates such as sapphire, spinel, cubic zirconia, strontium titanate and yttrium aluminium garnet (YAG: Er) will be discussed here in order to support some criteria that will allow to distinguish between them. While diamond shows emission bands due to nitrogen defects, simulants feature d-transition metals and rare earths such as Cr{sup 3+}, Mn{sup 2+}, Fe{sup 3+}, Ti{sup 3+} and Er{sup 3+} emissions.

  6. Long-term data storage in diamond

    Dhomkar, Siddharth; Henshaw, Jacob; Jayakumar, Harishankar; Meriles, Carlos A.


    The negatively charged nitrogen vacancy (NV−) center in diamond is the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Although most work so far has focused on the NV− optical and spin properties, control of the charge state promises complementary opportunities. One intriguing possibility is the long-term storage of information, a notion we hereby introduce using NV-rich, type 1b diamond. As a proof of principle, we use multicolor optical microscopy to read, write, and reset arbitrary data sets with two-dimensional (2D) binary bit density comparable to present digital-video-disk (DVD) technology. Leveraging on the singular dynamics of NV− ionization, we encode information on different planes of the diamond crystal with no cross-talk, hence extending the storage capacity to three dimensions. Furthermore, we correlate the center’s charge state and the nuclear spin polarization of the nitrogen host and show that the latter is robust to a cycle of NV− ionization and recharge. In combination with super-resolution microscopy techniques, these observations provide a route toward subdiffraction NV charge control, a regime where the storage capacity could exceed present technologies.

  7. Microstructural Characterisation and Wear Behaviour of Diamond Composite Materials

    Xing S. Li


    Full Text Available Since the initial research leading to the production of diamond composite materials, there have been several important developments leading to significant improvements in the properties of these superhard composite materials. Apart from the fact that diamonds, whether originating from natural resources or synthesised commercially, are the hardest and most wear-resistant materials commonly available, there are other mechanical properties that limit their industrial application. These include the low fracture toughness and low impact strength of diamond. By incorporating a range of binder phases into the sintering production process of these composites, these critically important properties have been radically improved. These new composites can withstand much higher operating temperatures without markedly reducing their strength and wear resistance. Further innovative steps are now being made to improve the properties of diamond composites by reducing grain and particle sizes into the nano range. This review will cover recent developments in diamond composite materials with special emphasis on microstructural characterisation. The results of such studies should assist in the design of new, innovative diamond tools as well as leading to radical improvements in the productivity of cutting, drilling and sawing operations in the exploration, mining, civil construction and manufacturing industries.

  8. 24-Hour Relativistic Bit Commitment

    Verbanis, Ephanielle; Martin, Anthony; Houlmann, Raphaël; Boso, Gianluca; Bussières, Félix; Zbinden, Hugo


    Bit commitment is a fundamental cryptographic primitive in which a party wishes to commit a secret bit to another party. Perfect security between mistrustful parties is unfortunately impossible to achieve through the asynchronous exchange of classical and quantum messages. Perfect security can nonetheless be achieved if each party splits into two agents exchanging classical information at times and locations satisfying strict relativistic constraints. A relativistic multiround protocol to achieve this was previously proposed and used to implement a 2-millisecond commitment time. Much longer durations were initially thought to be insecure, but recent theoretical progress showed that this is not so. In this Letter, we report on the implementation of a 24-hour bit commitment solely based on timed high-speed optical communication and fast data processing, with all agents located within the city of Geneva. This duration is more than 6 orders of magnitude longer than before, and we argue that it could be extended to one year and allow much more flexibility on the locations of the agents. Our implementation offers a practical and viable solution for use in applications such as digital signatures, secure voting and honesty-preserving auctions.

  9. Prediction of Crack for Drilling Process on Alumina Using Neural Network and Taguchi Method

    Kingsun Lee


    Full Text Available This study analyzes a variety of significant drilling conditions on aluminum oxide (with L18 orthogonal array using a diamond drill. The drilling parameters evaluated are spindle speed, feed rate, depth of cut, and diamond abrasive size. An orthogonal array, signal-to-noise (S/N ratio, and analysis of variance (ANOVA are employed to analyze the effects of these drilling parameters. The results were confirmed by experiments, which indicated that the selected drilling parameters effectively reduce the crack. The neural network is applied to establish a model based on the relationship between input parameters (spindle speed, feed rate, depth of cut, and diamond abrasive size and output parameter (cracking area percentage. The neural network can predict individual crack in terms of input parameters, which provides faster and more automated model synthesis. Accurate prediction of crack ensures that poor drilling parameters are not suitable for machining products, avoiding the fabrication of poor-quality products. Confirmation experiments showed that neural network precisely predicted the cracking area percentage in drilling of alumina.

  10. A brief review on quantum bit commitment

    Almeida, Álvaro J.; Loura, Ricardo; Paunković, Nikola; Silva, Nuno A.; Muga, Nelson J.; Mateus, Paulo; André, Paulo S.; Pinto, Armando N.


    In classical cryptography, the bit commitment scheme is one of the most important primitives. We review the state of the art of bit commitment protocols, emphasizing its main achievements and applications. Next, we present a practical quantum bit commitment scheme, whose security relies on current technological limitations, such as the lack of long-term stable quantum memories. We demonstrate the feasibility of our practical quantum bit commitment protocol and that it can be securely implemented with nowadays technology.

  11. A holistic approach to bit preservation

    Zierau, Eld


    Purpose: The purpose of this paper is to point out the importance of taking a holistic approach to bit preservation when setting out to find an optimal bit preservation solution for specific digital materials. In the last decade there has been an increasing awareness that bit preservation, which ...

  12. Drill-string torsional vibration suppression using GA optimized controllers

    Karkoub, M. [Texas A and M Univ. (Qatar); Abdel-Magid, Y.L. [Petroleum Inst., Abu Dhabi (United Arab Emirates); Balachandran, B. [Maryland Univ., College Park, MD (United States)


    When drilling an oil well, the drilling process is influenced by the dynamically induced vibrations resulting from design imperfections and material elasticity. Such torsional vibrations may cause premature wear and damage of drilling equipment and cause failure of drill-strings. Vibrations can also decrease the rate of penetration (ROP), and thus increase the cost of the well. In addition, vibrations can interfere with measurement-while-drilling (MWD) tools. This paper focused on drill-string dynamics and control, with particular reference to intelligent techniques that have been proposed for controller design, including genetic algorithms (GA). It reported on a study that addressed the problem of stick-slip friction at the drill-bit level. An oil well drill-string using proportional integral derivative (PID) controllers and lead-lag compensators was used together with a GA to reduce the stick-slip induced vibrations. Proposed control schemes were validated through computer simulations. The controllers were designed using different objective functions and parameter search limits. 21 refs., 1 tab., 12 figs.

  13. Development Status and Challenge of PetroChina's Deep Drilling Technologies

    Wang Haige; Zheng Xinquan


    @@ Deep and ultra-deep drilling technologies have been developed since the late 1930s, and got great achievements especially in the last two decades. The depth of well completion has even reached to 12 kilometers. Several countries, such as US and some European countries,are leading in the advanced deep and ultra-deep drilling technologies in the world. In recent years, nevertheless,PetroChina has also made big progress in mechanical penetration rate (ROP), drilling period, amount of drilling bit used in a single well of deep drilling as well as in deep drilling equipments. Compared with the high-level technologies of complicated deep drilling in the world,PetroChina still has a long way to go.

  14. Resonance: The science behind the art of sonic drilling

    Lucon, Peter Andrew

    the bit as the primary two control variables. The sonic drill can also be controlled using feedback from sensors mounted on the sonic drill head, which is the driver for the sonic drill located above ground

  15. Rock Drilling Performance Evaluation by an Energy Dissipation Based Rock Brittleness Index

    Munoz, H.; Taheri, A.; Chanda, E. K.


    To reliably estimate drilling performance both tool-rock interaction laws along with a proper rock brittleness index are required to be implemented. In this study, the performance of a single polycrystalline diamond compact (PDC) cutter cutting and different drilling methods including PDC rotary drilling, roller-cone rotary drilling and percussive drilling were investigated. To investigate drilling performance by rock strength properties, laboratory PDC cutting tests were performed on different rocks to obtain cutting parameters. In addition, results of laboratory and field drilling on different rocks found elsewhere in literature were used. Laboratory and field cutting and drilling test results were coupled with values of a new rock brittleness index proposed herein and developed based on energy dissipation withdrawn from the complete stress-strain curve in uniaxial compression. To quantify cutting and drilling performance, the intrinsic specific energy in rotary-cutting action, i.e. the energy consumed in pure cutting action, and drilling penetration rate values in percussive action were used. The results show that the new energy-based brittleness index successfully describes the performance of different cutting and drilling methods and therefore is relevant to assess drilling performance for engineering applications.

  16. BIT BY BIT: A Game Simulating Natural Language Processing in Computers

    Kato, Taichi; Arakawa, Chuichi


    BIT BY BIT is an encryption game that is designed to improve students' understanding of natural language processing in computers. Participants encode clear words into binary code using an encryption key and exchange them in the game. BIT BY BIT enables participants who do not understand the concept of binary numbers to perform the process of…

  17. A Holistic Approach to Bit Preservation

    Zierau, Eld Maj-Britt Olmütz


    for confidentiality, availability, costs, additional to the requirements of ensuring bit safety. A few examples are: • The way that digital material is represented in files and structures has an influence on whether it is possible to interpret and use the bits at a later stage. Consequentially, the way bits represent....... • There will be requirements for the availability of the bit preserved digital material in order to meet requirements on use of the digital material, e.g. libraries often need to give fast access to preserved digital material to the public, i.e. the availability of the bit preserved material must support the use...

  18. Investigation of the feasibility of deep microborehole drilling

    Dreesen, D.S. [Los Alamos National Lab., NM (United States); Cohen, J.H. [Maurer Engineering, Inc., Houston, TX (United States)


    Recent advances in sensor technology, microelectronics, and telemetry technology make it feasible to produce miniature wellbore logging tools and instrumentation. Microboreholes are proposed for subterranean telemetry installations, exploration, reservoir definition, and reservoir monitoring this assumes that very small diameter bores can be produced for significantly lower cost using very small rigs. A microborehole production concept based on small diameter hydraulic or pneumatic powered mechanical drilling, assemblies deployed on coiled tubing is introduced. The concept is evaluated using, basic mechanics and hydraulics, published theories on rock drilling, and commercial simulations. Small commercial drill bits and hydraulic motors were selected for laboratory scale demonstrations. The feasibility of drilling deep, directional, one to two-inch diameter microboreholes has not been challenged by the results to date. Shallow field testing of prototype systems is needed to continue the feasibility investigation.

  19. Chaotic Vibration Analysis of the Bottom Rotating Drill String

    Qilong Xue


    Full Text Available Drill string vibration is a widely studied topic. This paper developed a real-time measurement system near the drilling bit and extracted the lateral vibration, longitudinal vibration time series of bottom rotating drill string. In order to reconstruct the phase space, we estimated the delay time with mutual information and calculated the embedding dimension through Cao’s method. Finally, the chaotic characterization of the system is analyzed by calculating the correlation dimension and the largest Lyapunov exponent. The results show that such system can exhibit positive finite-time Lyapunov exponents and a clear convergence toward the correlation dimension, which is a strong indicator for the chaotic behavior of the system. It is expected that the new dynamics found in this paper could be of potential implication to the control methods of the drill string vibration.

  20. Global axial-torsional dynamics during rotary drilling

    Gupta, Sunit K.; Wahi, Pankaj


    We have studied the global dynamics of the bottom hole assembly (BHA) during rotary drilling with a lumped parameter axial-torsional model for the drill-string and a linear cutting force model. Our approach accounts for bit-bounce and stick-slip along with the regenerative effect and is independent of the drill-string and the bit-rock interaction model. Regenerative axial dynamics due to variable depth of cut is incorporated through a functional description of the cut surface profile instead of a delay differential equation with a state-dependent delay. The evolution of the cut surface is governed by a nonlinear partial differential equation (PDE) which is coupled with the ordinary differential equations (ODEs) governing the longitudinal and angular dynamics of the BHA. The boundary condition for the PDE captures multiple regeneration in the event of bit-bounce. Interruption in the torsional dynamics is included by considering separate evolution equations for the various states during the stick period. Finite-dimensional approximation for our coupled PDE-ODE model has been obtained and validated by comparing our results against existing results. Bifurcation analysis of our system reveals a supercritical Hopf bifurcation leading to periodic vibrations without bit-bounce and stick-slip which is followed by solutions involving bit-bounce or stick-slip depending on the operating parameters. Further inroads into the unstable regime leads to a variety of complex behavior including co-existence of periodic and chaotic solutions involving both bit-bounce and stick-slip.


    Mihai ISPAS


    Full Text Available Pre-laminated particleboard is a wood based composite extensively used in the furniture industry. Drilling is the most common machining process which prepares the panels for joining using twist/helical drills in the absolute majority of cases. The point angle of the drill bit and the feed speed during drilling play a major role in gaining a good surface quality and minimizing the delamination tendency of the pre-laminated particleboard. The objective of this study was to measure and analyze the influence of the two above-mentioned factors on the processing quality, evaluated by de size of delaminations, both, at the entrance side and the exit side of the drill bit. To assess the defect, two parameters were used: the delamination factor and the effective area of delamination. The results showed that, in general, the combination of small point angle with low feed rate minimizes the delamination of pre-laminated particleboard panels at drilling.

  2. Development of a Piezoelectric Rotary Hammer Drill

    Domm, Lukas N.


    The Piezoelectric Rotary Hammer Drill is designed to core through rock using a combination of rotation and high frequency hammering powered by a single piezoelectric actuator. It is designed as a low axial preload, low mass, and low power device for sample acquisition on future missions to extraterrestrial bodies. The purpose of this internship is to develop and test a prototype of the Piezoelectric Rotary Hammer Drill in order to verify the use of a horn with helical or angled cuts as a hammering and torque inducing mechanism. Through an iterative design process using models in ANSYS Finite Element software and a Mason's Equivalent Circuit model in MATLAB, a horn design was chosen for fabrication based on the predicted horn tip motion, electromechanical coupling, and neutral plane location. The design was then machined and a test bed assembled. The completed prototype has proven that a single piezoelectric actuator can be used to produce both rotation and hammering in a drill string through the use of a torque inducing horn. Final data results include bit rotation produced versus input power, and best drilling rate achieved with the prototype.

  3. Fabrication of diamond shells

    Hamza, Alex V.; Biener, Juergen; Wild, Christoph; Woerner, Eckhard


    A novel method for fabricating diamond shells is introduced. The fabrication of such shells is a multi-step process, which involves diamond chemical vapor deposition on predetermined mandrels followed by polishing, microfabrication of holes, and removal of the mandrel by an etch process. The resultant shells of the present invention can be configured with a surface roughness at the nanometer level (e.g., on the order of down to about 10 nm RMS) on a mm length scale, and exhibit excellent hardness/strength, and good transparency in the both the infra-red and visible. Specifically, a novel process is disclosed herein, which allows coating of spherical substrates with optical-quality diamond films or nanocrystalline diamond films.

  4. Functionalized diamond nanoparticles

    Beaujuge, Pierre M.


    A diamond nanoparticle can be functionalized with a substituted dienophile under ambient conditions, and in the absence of catalysts or additional reagents. The functionalization is thought to proceed through an addition reaction.

  5. Diamond nanobeam waveguide optomechanics

    Khanaliloo, Behzad; Hryciw, Aaron C; Lake, David P; Kaviani, Hamidreza; Barclay, Paul E


    Optomechanical devices sensitively transduce and actuate motion of nanomechanical structures using light, and are central to many recent fundamental studies and technological advances. Single--crystal diamond promises to improve the performance of optomechanical devices, while also providing opportunities to interface nanomechanics with diamond color center spins and related quantum technologies. Here we demonstrate measurement of diamond nanobeam resonators with a sensitivity of 9.5 fm/Hz^0.5 and bandwidth >120 nm through dissipative waveguide--optomechanical coupling. Nanobeams are fabricated from bulk single--crystal diamond using a scalable quasi--isotropic oxygen plasma undercut etching process, and support mechanical resonances with quality factor of 2.5 x 10^5 at room temperature, and 7.2 x 10^5 in cryogenic conditions (5K). Mechanical self--oscillations, resulting from interplay between optomechanical coupling and the photothermal response of nanobeams in a buckled state, are observed with amplitude e...

  6. Quantum engineering: Diamond envy

    Nunn, Joshua


    Nitrogen atoms trapped tens of nanometres apart in diamond can now be linked by quantum entanglement. This ability to produce and control entanglement in solid systems could enable powerful quantum computers.

  7. Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

    Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart


    The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a

  8. Diamond dipole active antenna

    Bubnov, Igor N.; Falkovych, I. S.; Gridin, A. A.; Stanislavsky, A. A.; Reznik, A. P.


    Advantages of the diamond dipole antenna as an active antenna are presented. Such an antenna is like an inverted bow-tie antenna, but the former has some advantages over the ordinary bow-tie antenna. It is shown that the diamond dipole antenna may be an effective element of a new antenna array for low-frequency radio astronomy as well as a communication antenna.

  9. Comprehensive borehole management for shorter drilling time; Umfassendes Bohrfortschrittsmanagement zur Verkuerzung der Bohrprojektdauer

    Roehrlich, M. [ExxonMobil Production Deutschland GmbH, Hannover (Germany)


    In 2006, the trademarked ExxonMobil Fast Drill Process (FDP) was introduced also in the German ExxonMobil boreholes. The process is to maximize the drilling speed for every meter drilled. The process makes it possible to ensure borehole management on the basis of quantitative data and in consideration of all phases that are relevant for sinking a borehole. The FDP is used world-wide in all ExxonMobil drilling departments. More than 1.35 million meters are drilled annually in many different boreholes with different geological conditions, drilling profiles and international sites. The results were similar in many cases, with a significant increase in ROP and drill bit life, and with less damage caused by vibrations. FDP was developed on the basis of real time monitoring of the specific mechanical energy (MSE) required for drilling. MSE monitoring was found to be an effective tool dor detecting inefficient functioning of the drill bit and the overall system. To make operation more efficient, the causes must be identified and measures must be taken accordingly, taking into account the potential risks involved in such measures. MSE monitoring is a tool while FDPL is a broad management process ensuring that MSE and many other data sources are used effectively for optimisation of the ROP. Consequent implementation of the process resulted in a significant increase of the ROP. The major elements required for achieving this goal are discussed. (orig.)

  10. Quality in drilling operations

    Duncan, E.; Gervais, I. [Sedco Forex Jacintoport Facility, Channelview, TX (United States); Le Moign, Y.; Pangarkar, S.; Stibbs, B. [Sedco Forex, Montrouge (France); McMorran, P. [Sedco Forex, Pau (France); Nordquist, E. [Dubai Petroleum Company, Dubai (United Arab Emirates); Pittman, T. [Sedco Forex, Perth (Australia); Schindler, H. [Sedco Forex, Dubai (United Arab Emirates); Scott, P. [Woodside Offshore Petroleum Pty. Ltd., Perth (Australia)


    Driven by cost and profitability pressures, quality has taken on new meaning and importance in the oil field during the past decade. In drilling operations, new initiatives have led to cooperative team efforts between operators and drilling contractors to enhance quality. In this article examples are given of how one drilling contractor, by adopting a quality culture, is reaping major benefits for its clients as well as its employees. 22 figs., 19 refs.

  11. Hard rock drilling: from conventional technologies to the potential use of laser; Perfuracao em rochas duras: das tecnologias convencionais ate o potencial uso do laser

    Amaro, Renato; Lomba, Rosana Fatima Teixieira [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Perez, Maria Angelica Acosta; Valente, Luiz Carlos Guedes; Braga, Arthur Martins Barbosa [Pontificia Universidade Catolica do Rio de Janeiro (PUC-Rio), RJ (Brazil)


    One of the biggest challenges in the drilling of the carbonate rocks of the Pre-salt is to overcome the low penetration rates that have been obtained in the drilling of the reservoir rock in the vertical and directional wells. To overcome this challenge, a great effort is being developed in several lines of research, both in developing new concepts in drill bits and in the selection of a drilling system that together with appropriate type of bit provide an expected improvement in performance. To achieve these results, procedures are being prioritized and drilling systems with lower vibration levels are being used, since this phenomenon of vibration reduces the performance of penetration rate also affecting the lifetime of the equipment and consequently causes a reduction in reliability of all system and raises the cost per meter of drilling. Thus, new drill bit technology and new drilling systems are under development and, among these technologies we can distinguish those that promote improvements in conventional technologies and innovative technologies frankly which uses new mechanisms to cut or weaken the rock. This paper presents an overview of the conventional technology of drilling systems and drill bits, and provides information about the researches that have been developed with the use of innovative technologies which is presented as highly promising, among these innovative technologies, laser drilling and the drilling itself assisted by laser. In this process the laser beam has the main function to weaken the rock improving the rate of penetration. This paper presents a summary of studies and analyzes which are underway to investigate the potential of laser technology, also presents some results of laboratory tests already carried out. The drilling fluid in which the laser will have to pass through in the future applications is analyzed on the approach of their physicochemical properties. Thus, a better understanding of the interaction with the drilling

  12. Stability of single skyrmionic bits

    Vedmedenko, Olena; Hagemeister, Julian; Romming, Niklas; von Bergmann, Kirsten; Wiesendanger, Roland

    The switching between topologically distinct skyrmionic and ferromagnetic states has been proposed as a bit operation for information storage. While long lifetimes of the bits are required for data storage devices, the lifetimes of skyrmions have not been addressed so far. Here we show by means of atomistic Monte Carlo simulations that the field-dependent mean lifetimes of the skyrmionic and ferromagnetic states have a high asymmetry with respect to the critical magnetic field, at which these lifetimes are identical. According to our calculations, the main reason for the enhanced stability of skyrmions is a different field dependence of skyrmionic and ferromagnetic activation energies and a lower attempt frequency of skyrmions rather than the height of energy barriers. We use this knowledge to propose a procedure for the determination of effective material parameters and the quantification of the Monte Carlo timescale from the comparison of theoretical and experimental data. Financial support from the DFG in the framework of the SFB668 is acknowledged.

  13. Bit threads and holographic entanglement

    Freedman, Michael


    The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner...

  14. Mourning in Bits and Stone

    Sabra, Jakob Borrits

    We mourn our dead, publicly and privately, online and offline. Cemeteries, web memorials and social network sites make up parts of todays intricately weaved and interrelated network of death, grief and memorialization practices [1]–[5]. Whether cut in stone or made of bits, graves, cemeteries, me...... and memorialization by discussing the publicly and privately digital and social death from a spatial, temporal, physical and digital angle. Further the paper will reflect on how to encompass shifting trends and technologies in ‘traditional’ spaces of mourning and remembrance.......We mourn our dead, publicly and privately, online and offline. Cemeteries, web memorials and social network sites make up parts of todays intricately weaved and interrelated network of death, grief and memorialization practices [1]–[5]. Whether cut in stone or made of bits, graves, cemeteries......, memorials, monuments, websites and social networking services (SNS) all are alterable, controllable and adaptive. They represent a certain rationale contrary to the emotive state of mourning (e.g. gravesites function as both spaces of internment and places of spiritual and emotional recollection). Following...

  15. Bit Threads and Holographic Entanglement

    Freedman, Michael; Headrick, Matthew


    The Ryu-Takayanagi (RT) formula relates the entanglement entropy of a region in a holographic theory to the area of a corresponding bulk minimal surface. Using the max flow-min cut principle, a theorem from network theory, we rewrite the RT formula in a way that does not make reference to the minimal surface. Instead, we invoke the notion of a "flow", defined as a divergenceless norm-bounded vector field, or equivalently a set of Planck-thickness "bit threads". The entanglement entropy of a boundary region is given by the maximum flux out of it of any flow, or equivalently the maximum number of bit threads that can emanate from it. The threads thus represent entanglement between points on the boundary, and naturally implement the holographic principle. As we explain, this new picture clarifies several conceptual puzzles surrounding the RT formula. We give flow-based proofs of strong subadditivity and related properties; unlike the ones based on minimal surfaces, these proofs correspond in a transparent manner to the properties' information-theoretic meanings. We also briefly discuss certain technical advantages that the flows offer over minimal surfaces. In a mathematical appendix, we review the max flow-min cut theorem on networks and on Riemannian manifolds, and prove in the network case that the set of max flows varies Lipshitz continuously in the network parameters.

  16. Drilling cost-cutting

    Capuano, L.E. Jr.


    This presentation by Louis E. Capuano, Jr., President, ThermaSource, Inc., discusses cost-cutting in the drilling phase of geothermal energy exploration and production. All aspects of a geothermal project including the drilling must be streamlined to make it viable and commercial. If production could be maximized from each well, there would be a reduction in drilling costs. This could be achieved in several ways, including big hole and multi-hole completion, directional drilling, better knowledge of the resource and where to penetrate, etc.

  17. System and method for damping vibration in a drill string

    Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E; Perry, Carl Allison


    A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

  18. Drilling efficiency and temperature elevation of three types of Kirschner-wire point.

    Piska, M; Yang, L; Reed, M; Saleh, M


    An innovative Kirschner (K-) wire point was developed and compared in fresh pig femora in terms of drilling efficiency and temperature elevation with the trochar and diamond points currently used in clinical practice. The tips of thermal couples were machined to the defined geometry and the temperature measured during drilling. Using the same drill speed (rev/min) and feed rate, the new K-wire point produced the lowest thrust force and torque as measured by a Kistler dynamometer. Drill point temperatures were highest with the trochar geometry (129 +/- 6 degrees C), followed by the diamond (98 +/- 7 degrees C). The lowest temperatures were recorded with the Medin K-wire (66 +/- 2 degrees C). On repeated drilling it could be used for up to 30 holes before reaching the less satisfactory drill performance of the diamond tip. The new K-wire provides a better alternative as it requires less effort for insertion, generates less heat and may be re-used.

  19. Development and Manufacture of Cost-Effective Composite Drill Pipe

    James C. Leslie


    fields up to 74 kilohertz (KHz), a removable section of copper wire can be placed inside the composite pipe to short the tool joints electrically allowing electromagnetic signals inside the collar to induce and measure the same within the rock formation. By embedding a pair of wires in the composite section and using standard drill pipe box and pin ends equipped with a specially developed direct contact joint electrical interface, power can be supplied to measurement-while-drilling (MWD) and logging-while-drilling (LWD) bottom hole assemblies. Instantaneous high-speed data communications between near drill bit and the surface are obtainable utilizing this 'smart' drilling technology. The composite drill pipe developed by ACPT has been field tested successfully in several wells nationally and internationally. These tests were primarily for short radius and ultra short radius directional drilling. The CDP in most cases performed flawlessly with little or no appreciable wear. ACPT is currently marketing a complete line of composite drill collars, subs, isolators, casing, and drill pipe to meet the drilling industry's needs and tailored to replace metal for specific application requirements.

  20. Optimizing Geothermal Drilling: Oil and Gas Technology Transfer

    Tilley, Mitch; Eustes, Alfred; Visser, Charles; Baker, Walt; Bolton, Dan; Bell, Jason; Nagandran, Uneshddarann; Quick, Ralph


    There is a significant amount of financial risk associated with geothermal drilling; however, there are opportunities to improve upon current practices and technologies used. The scope of this drilling operational study included 21 geothermal wells and 21 oil and gas wells. The goal was to determine a 'perfect well' using historical data to compare the best oil and gas well to the best geothermal well. Unfortunately, limitations encountered in the study included missing data (bit records, mud information, etc.), poor data collection, and difficult to ascertain handwriting. An online software database was used to format drilling data to IADC coded daily drilling reports and generate analysis figures. Six major issues have been found in geothermal drilling operations. These problems include lost circulation, rig/equipment selection, cementing, penetration rate, drilling program, and time management. As a result of these issues, geothermal drilling averages 56.4 days longer than drilling comparable oil and gas wells in the wells in this study. Roughly $13.9 million would be lost due to non-productive time in the 21 geothermal wells and only $1.3 million in the oil and gas wells, assuming a cost of $50,000 per day. Comparable events such as drilling the same sized hole, tripping in/out, cementing, and running the same size casing took substantially less time in the oil and gas wells. Geothermal wells were drilled using older and/or less advanced technology to depths less than 10,000 feet, while oil and gas wells reached 12,500 feet faster with purpose built rigs. A new approach is now underway that will optimize drilling programs throughout the drilling industry. It is the use of Mechanical Specific Energy (MSE) as a tool to realize efficient drilling processes. However, a work-flow must also be established in order for there to be an efficient drilling program. Potential improvements for current geothermal operations are: the use of electronic records, real

  1. Horizontal drilling in Ontario

    Sidey, P.; Precul, L. [Sproule Associates Ltd., Calgary, AB (Canada)


    A review of oil and gas production in Ontario was presented with particular reference to drilling activity between 1987 to mid 2002 when 1450 vertical wells were drilled, of which 1100 were for petroleum production and the remainder were for gas storage, observation wells, private gas wells and stratigraphic tests. Of the 1100 vertical wells drilled for petroleum production, 40 per cent became gas wells, 16 per cent became oil wells, 4 per cent became oil and gas wells, and 40 per cent were dry. During the same time period, 133 horizontal wells were also drilled, mostly for petroleum. The most active operator was Talisman Energy, which drilled 101 of the 133 horizontal wells. The remainder were drilled by 12 other companies. Of the horizontal wells, 64 per cent became oil wells, 19 per cent became gas wells, and 17 per cent were dry. This presentation included graphs depicting which oil and gas pools saw vertical or horizontal drilling during the designated time period, and explained how the wells were classified. Both horizontal and vertical well targets were illustrated. Particular reference was made to Talisman Energy's Lake Erie Drilling program which revealed that horizontal wells have an initial production rate that is 5 times that expected from vertical wells. The Hillman Pool case study revealed that the initial rate of the average horizontal well is less than half that of the average vertical well. Horizontal drilling in the Lake Erie Morpeth Gas pool has also been a commercial success. This paper demonstrates that operators have maintained Ontario's oil and gas production at high levels. In 1997 widespread horizontal drilling began taking place in Ontario, and since then, approximately 30 per cent of the wells drilled in the province have been horizontal. 16 figs.

  2. Cryotribology of diamond and graphite

    Iwasa, Yukikazu; Ashaboglu, A.F.; Rabinowicz, E.R. [Francis Bitter Magnet Lab., Cambridge, MA (United States)


    An experimental study was carried out on the tribological behavior of materials of interest in cryogenic applications, focusing on diamond and graphite. Both natural diamond (referred in the text as diamond) and chemical-vapor-deposition (CVD) diamond (CVD-diamond) were used. The experiment was carried out using a pin-on-disk tribometer capable of operating at cryogenic temperatures, from 4.2 to 293 K. Two basic scenarios of testing were used: (1) frictional coefficient ({mu}) vs velocity (v) characteristics at constant temperatures; (2) {mu} vs temperature (T) behavior at fixed sliding speeds. For diamond/CVD-diamond, graphite/CVD-diamond, stainless steel/CVD-diamond pairs, {mu}`s are virtually velocity independent. For each of diamond/graphite, alumina/graphite, and graphite/graphite pairs, the {partial_derivative}{mu}/{partial_derivative}v characteristic is favorable, i.e., positive. For diamond/CVD-diamond and graphite/CVD-diamond pairs, {mu}`s are nearly temperature independent between in the range 77 - 293 K. Each {mu} vs T plot for pin materials sliding on graphite disks has a peak at a temperature in the range 100 - 200 K.

  3. Nanocrystalline, superhard, ductile ceramic coatings for roller-cone bit bearings

    Namavar, F.; Colter, P.; Karimy, H. [Spire Corp., Bedford, MA (United States)] [and others


    The established method for construction of roller bits utilizes carburized steel, frequently with inserted metal bearing surfaces. This construction provides the necessary surface hardness while maintaining other desirable properties in the core. Protective coatings are a logical development where enhanced hardness, wear resistance, corrosion resistance, and surface properties are required. The wear properties of geothermal roller-cone bit bearings could be further improved by application of protective ceramic hard coatings consisting of nanometer-sized crystallites. Nanocrystalline protective coatings provide the required combination of hardness and toughness which has not been available thus far using traditional ceramics having larger grains. Increased durability of roller-cone bit bearings will ultimately reduce the cost of drilling geothermal wells through increased durability.

  4. Big hole of second section of Well Mashen-1 optimized drilling technology%马深1井二开大井眼优快钻井技术

    冯林; 母亚军; 杨代明; 周喜勇; 汤分周


    马深1井是中石化部署在川东北通南巴构造带马路背构造高部位上的一口重点预探井,完钻井深8418 m,二开Ø444.5 mm/Ø406.4 mm 大井眼钻达4295 m,为该地区最深大井眼段。该井段以陆相地层为主,地质条件复杂,地层可钻性差,井壁不稳定以及地层软硬交错且倾角较大,且在水力参数和破岩能量等方面存在一系列问题。针对不同地层特征和岩石性质,优选了气体钻井、大扭矩螺杆+PDC、涡轮+孕镶、混合钻头、旋冲工具等多项新技术、新工具,基于动力学防斜打快理论,在保证井身质量的前提下大幅提高了机械钻速。同时,自主研制了 KCl 聚胺防塌钻井液体系,有效解决了井壁失稳的问题。%Well Mashen-1 is a keyvertical exploration well which located at high part of Malubei structure of Tongnanba structure belt and was deployed by SINOPEC. The main part of this well is continental formation.This area is with complex geological conditions, poor drillability, the problem of bore-hole stability, formation alternating hard and soft,and dip angle is bigger. And in the hydraulic pa-rameters and break-rock energy, as well as a series of problems. Through in-depth study and analysis. According to different strata char-acteristics and rock properties, the application of gas drilling, high torque screw + PDC, turbine + impregnated diamond bit, hybrid bit and rotary percussion tool such as new drilling technology and new tools are optimized. Based on the theory of dynamic anti oblique and fast drilling.Ensure wellbore quality and effectively improve mechanical drilling speed. At the same time, adopted the self-developed KCl polyamine an-ti-cavingcapacities drilling fluid system. This technique successfully cope with the wellbore instability.

  5. 磨料水射流钻头破岩过程的力学分析%Mechanical analysis of rock breaking by an abrasive water jet bit

    卢义玉; 沈晓莹; 汤积仁; 夏彬伟; 王景环


    The boss at the hole bottom is a key factor that limits drilling speed. The boss was eliminated and drilling speed increased by using an abrasive water jet bit to drill in hard rock. Force analysis shows that the mode of rock breaking during hard rock drilling by a three wings bit is by grinding. However, the mode is by cutting when an abrasive water jet is used. Hard rock drilling experiments showed that the drilling speed was 1. 57 times faster using an improved bit with reduced blade distance of the leading bit compared to the original three wings bit. At the same time torque increased by 11.3%, and the observed wear is serious. The drill- ing speed using an abrasive water jet bit is 3.72 times faster than the original three wings bit and the torque is reduced by 34.0% with no evident wear. Theoretical analysis and experimen- tal results showed that low drilling speeds and serious wear encountered while drilling in hard rock can be completely resolved by using an abrasive water jet bit.%研究发现钻孔孔底凸台是限制钻头钻进速度的关键因素,为了消除凸台,提高钻进速度,提出利用磨料水射流钻头破碎硬岩.对原三翼钻头和磨料水射流钻头破岩过程进行了受力分析得出原三翼钻头硬岩钻进时破岩方式为磨削,磨料水射流钻头破岩方式为切削.实验室硬岩钻进实验表明:缩小前导钻头刀片间距的改良型钻头钻进速度是原三翼钻头的1.57倍,扭矩比原三翼钻头增大了11.3%,且磨损加剧;磨料水射流钻头钻进速度是原三翼钻头的3.72倍,扭矩比原三翼钻头减小34.0%,未见明显磨损.理论分析和实验结果表明,磨料水射流钻头从根本上解决了硬岩钻进时速度慢,刀具磨损大的问题.

  6. In bits, bytes and stone

    Sabra, Jakob Borrits; Andersen, Hans Jørgen

    The digital spheres of Information and Communication Technologies (ICT) and Social Network Services (SNS) are influencing 21st. century death. Today the dying and the bereaved attend mourning and remembrance both online and offline. Combined, the cemeteries, web memorials and social network sites...... designs'. Urns, coffins, graves, cemeteries, memorials, monuments, websites, applications and software services, whether cut in stone or made of bits, are all influenced by discourses of publics, economics, power, technology and culture. Designers, programmers, stakeholders and potential end-users often...... do not recognize the need or potential of working with or using, specific 'death-services/products', since they find little or no comfort in contemplating, working or playing around with the concept of death and its life changing consequences. Especially not while being alive and well...

  7. FastBit Reference Manual

    Wu, Kesheng


    An index in a database system is a data structure that utilizes redundant information about the base data to speed up common searching and retrieval operations. Most commonly used indexes are variants of B-trees, such as B+-tree and B*-tree. FastBit implements a set of alternative indexes call compressed bitmap indexes. Compared with B-tree variants, these indexes provide very efficient searching and retrieval operations by sacrificing the efficiency of updating the indexes after the modification of an individual record. In addition to the well-known strengths of bitmap indexes, FastBit has a special strength stemming from the bitmap compression scheme used. The compression method is called the Word-Aligned Hybrid (WAH) code. It reduces the bitmap indexes to reasonable sizes and at the same time allows very efficient bitwise logical operations directly on the compressed bitmaps. Compared with the well-known compression methods such as LZ77 and Byte-aligned Bitmap code (BBC), WAH sacrifices some space efficiency for a significant improvement in operational efficiency. Since the bitwise logical operations are the most important operations needed to answer queries, using WAH compression has been shown to answer queries significantly faster than using other compression schemes. Theoretical analyses showed that WAH compressed bitmap indexes are optimal for one-dimensional range queries. Only the most efficient indexing schemes such as B+-tree and B*-tree have this optimality property. However, bitmap indexes are superior because they can efficiently answer multi-dimensional range queries by combining the answers to one-dimensional queries.

  8. Bit-coded regular expression parsing

    Nielsen, Lasse; Henglein, Fritz


    Regular expression parsing is the problem of producing a parse tree of a string for a given regular expression. We show that a compact bit representation of a parse tree can be produced efficiently, in time linear in the product of input string size and regular expression size, by simplifying...... the DFA-based parsing algorithm due to Dub ´e and Feeley to emit the bits of the bit representation without explicitly materializing the parse tree itself. We furthermore show that Frisch and Cardelli’s greedy regular expression parsing algorithm can be straightforwardly modified to produce bit codings...

  9. Diamond electronic properties and applications

    Kania, Don R


    The use of diamond in electronic applications is not a new idea, but limitations in size and control of properties restricted the use of diamond to a few specialised applications. The vapour-phase synthesis of diamond, however, has facilitated serious interest in the development of diamond-based electronic devices. The process allows diamond films to be laid down over large areas. Both intrinsic and doped diamond films have a unique combination of extreme properties for high speed, high power and high temperature applications. The eleven chapters in Diamond: Electronic Properties and Applications, written by the world's foremost experts on the subject, give a complete characterisation of the material, in both intrinsic and doped forms, explain how to grow it for electronic applications, how to use the grown material, and a description of both passive and active devices in which it has been used with success. Diamond: Electronic Properties and Applications is a compendium of the available literature on the sub...

  10. Optimization of process parameters in drilling of fibre hybrid composite using Taguchi and grey relational analysis

    Vijaya Ramnath, B.; Sharavanan, S.; Jeykrishnan, J.


    Nowadays quality plays a vital role in all the products. Hence, the development in manufacturing process focuses on the fabrication of composite with high dimensional accuracy and also incurring low manufacturing cost. In this work, an investigation on machining parameters has been performed on jute-flax hybrid composite. Here, the two important responses characteristics like surface roughness and material removal rate are optimized by employing 3 machining input parameters. The input variables considered are drill bit diameter, spindle speed and feed rate. Machining is done on CNC vertical drilling machine at different levels of drilling parameters. Taguchi’s L16 orthogonal array is used for optimizing individual tool parameters. Analysis Of Variance is used to find the significance of individual parameters. The simultaneous optimization of the process parameters is done by grey relational analysis. The results of this investigation shows that, spindle speed and drill bit diameter have most effect on material removal rate and surface roughness followed by feed rate.

  11. Drilling in cortical bone: a finite element model and experimental investigations.

    Lughmani, Waqas A; Bouazza-Marouf, Kaddour; Ashcroft, Ian


    Bone drilling is an essential part of many orthopaedic surgery procedures, including those for internal fixation and for attaching prosthetics. Estimation and control of bone drilling forces are critical to prevent drill-bit breakthrough, excessive heat generation, and mechanical damage to the bone. An experimental and computational study of drilling in cortical bone has been conducted. A 3D finite element (FE) model for prediction of thrust forces experienced during bone drilling has been developed. The model incorporates the dynamic characteristics involved in the process along with geometrical considerations. An elastic-plastic material model is used to predict the behaviour of cortical bone during drilling. The average critical thrust forces and torques obtained using FE analysis are found to be in good agreement with the experimental results.

  12. Distributed downhole drilling network

    Hall, David R.; Hall, Jr., H. Tracy; Fox, Joe; Pixton, David S.


    A high-speed downhole network providing real-time data from downhole components of a drilling strings includes a bottom-hole node interfacing to a bottom-hole assembly located proximate the bottom end of a drill string. A top-hole node is connected proximate the top end of the drill string. One or several intermediate nodes are located along the drill string between the bottom-hole node and the top-hole node. The intermediate nodes are configured to receive and transmit data packets transmitted between the bottom-hole node and the top-hole node. A communications link, integrated into the drill string, is used to operably connect the bottom-hole node, the intermediate nodes, and the top-hole node. In selected embodiments, a personal or other computer may be connected to the top-hole node, to analyze data received from the intermediate and bottom-hole nodes.

  13. Advanced drilling systems study.

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis (Livesay Consultants, Encintas, CA)


    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  14. Diamond pixel modules

    Gan, K K; Robichaud, A; Potenza, R; Kuleshov, S; Kagan, H; Kass, R; Wermes, N; Dulinski, W; Eremin, V; Smith, S; Sopko, B; Olivero, P; Gorisek, A; Chren, D; Kramberger, G; Schnetzer, S; Weilhammer, P; Martemyanov, A; Hugging, F; Pernegger, H; Lagomarsino, S; Manfredotti, C; Mishina, M; Trischuk, W; Dobos, D; Cindro, V; Belyaev, V; Duris, J; Claus, G; Wallny, R; Furgeri, A; Tuve, C; Goldstein, J; Sciortino, S; Sutera, C; Asner, D; Mikuz, M; Lo Giudice, A; Velthuis, J; Hits, D; Griesmayer, E; Oakham, G; Frais-Kolbl, H; Bellini, V; D'Alessandro, R; Cristinziani, M; Barbero, M; Schaffner, D; Costa, S; Goffe, M; La Rosa, A; Bruzzi, M; Schreiner, T; de Boer, W; Parrini, G; Roe, S; Randrianarivony, K; Dolenc, I; Moss, J; Brom, J M; Golubev, A; Mathes, M; Eusebi, R; Grigoriev, E; Tsung, J W; Mueller, S; Mandic, I; Stone, R; Menichelli, D


    With the commissioning of the LHC in 2010 and upgrades expected in 2015, ATLAS and CMS are planning to upgrade their innermost tracking layers with radiation hard technologies. Chemical Vapor Deposition diamond has been used extensively in beam conditions monitors as the innermost detectors in the highest radiation areas of BaBar, Belle, CDF and all LHC experiments. This material is now being considered as a sensor material for use very close to the interaction region where the most extreme radiation conditions exist Recently the RD42 collaboration constructed, irradiated and tested polycrystalline and single-crystal chemical vapor deposition diamond sensors to the highest fluences expected at the super-LHC. We present beam test results of chemical vapor deposition diamond up to fluences of 1.8 x 10(16) protons/cm(2) illustrating that both polycrystalline and single-crystal chemical vapor deposition diamonds follow a single damage curve. We also present beam test results of irradiated complete diamond pixel m...

  15. Heteroepitaxial diamond growth

    Markunas, R. J.; Rudder, R. A.; Posthill, J. B.; Thomas, R. E.; Hudson, G.


    Technical highlights from 1993 include the following: Growth Chemistries: A clear correlation was observed between ionization potential of feedstock gasses and critical power necessary for inductive coupling of the plasma and consequent diamond growth. Substrate preparation and epitaxial film quality: Ion-implantation of C and O has been coupled with either electrochemical etching or acid cleaning for surface preparation prior to homoepitaxial growth. Reactor modifications: Key improvements were made to the RF reactor to allow for long growths to consolidate substrates. Liquid mass flow controllers were added to precisely meter both the water and selected alcohol. Ion-implantation and lift off: Lift off of diamond platelets has been achieved with two processes. Ion-implantation of either C or O followed by annealing and implantation of either C or O followed by water based electrolysis. Diamond characterization: Development of novel detect characterization techniques: (1) Etch delineation of defects by exposure to propane torch flame. (2) Hydrogen plasma exposure to enhance secondary electron emission and provide non-topographical defect contrast. Acetylene will react at room temperature with sites created by partial desorption of oxygen from the (100) diamond surface. Thermal desorption measurements give an apparent activation energy for CO desorption from diamond (100) of 45 kcal/mol. Quantum chemical calculations indicate an activation energy of 38 kcal/mol for CO desorption. Ab initio calculations on (100) surfaces indicates that oxygen adsorbed at one dimer site has an effect on the dimerization of an adjacent site.

  16. New sapphire and ruby components and their manufacture using diamond abrasives

    Sauser, D.

    The properties of synthetic aluminum oxides (sapphire and ruby) and their applications in watchmaking (watch bearings and watchglasses) and as hard-wearing components such as centering devices for optical fibres and water jet nozzles for material cutting are discussed. Examples are given of the use of diamonds tools for machining such components, including sawing, drilling, grinding and polishing operations.

  17. An all-optical system designed for the heating and temperature measurement of the diamond tool

    Masina, BN


    Full Text Available tool in the laboratory is important in the study of changes that occur in diamond tools, particularly the reduced efficiency of such tools in applications as rock drilling where extreme heating due to friction is expected. The results show that laser...

  18. Regression Modeling Of Cutting Parameters' Effect To Cutting Forces And Hole Surface Qualities In Drilling Of Dievar Hot Work Tool Steel

    İskender Özkul


    Full Text Available In this study, cutting moments, surface roughness, dimensional accuracy and circularity deviation values were investigated during drilling on Dievar degree of hot work tool steels with various drill bits. The experiments, was completed with Ø16 mm diameter uncoated carbide drill bits and TiAlN coated self-reamed carbide drill bits using coolant fluid on vertical machining center. In experiments, feed rate 0,16 mm/rev and the cutting speed 36, 40, 44, 48 m/min rates were used. The results were modeled by the method of linear regression and polynomial regression curve. Then they were compared with values equal significance. At the same time by analysis of variance, the cutting speed and drill type were investigated on the results of axial feed force, cutting torque, surface roughness, dimensional accuracy and circularity the deviation.

  19. Kick Detection at the Bit: Early Detection via Low Cost Monitoring

    Tost, Brian [National Energy Technology Lab. (NETL), Albany, OR (United States). Oak Ridge Inst. for Science and Education (ORISE); Rose, Kelly [National Energy Technology Lab. (NETL), Albany, OR (United States); Aminzadeh, Fred [Univ. of Southern California, Los Angeles, CA (United States). Dept. of Petroleum Engineering; Ante, Magdalene A. [Univ. of Southern California, Los Angeles, CA (United States). Dept. of Petroleum Engineering; Huerta, Nicolas [National Energy Technology Lab. (NETL), Albany, OR (United States)


    Formation fluid influxes (i.e. kicks) pose persistent challenges and operational costs during drilling operations. Implications of kicks range in scale but cumulatively result in substantial costs that affect drilling safety, environment, schedule, and infrastructure. Early kick detection presents a low-cost, easily adopted solution for avoiding well control challenges associated with kicks near the bit. Borehole geophysical tools used during the drilling process as part of the logging-while-drilling (LWD) and measurement-while-drilling (MWD) provide the advantage of offering real-time downhole data. LWD/MWD collect data on both the annulus and borehole wall. The annular data are normally treated as background, and are filtered out to isolate the formation measurements. Because kicks will change the local physical properties of annular fluids, bottom-hole measurements are among the first indicators that a formation fluid has invaded the wellbore. This report describes and validates a technique for using the annular portion of LWD/MWD data to facilitate early kick detection using first order principles. The detection technique leverages data from standard and cost-effective technologies that are typically implemented during well drilling, such as MWD/LWD data in combination with mud-pulse telemetry for data transmission.

  20. Electrical properties of laser-bonded Silicon-On-Diamond samples

    Sciortino, S., E-mail: [National Institute for Nuclear Physics, INFN, Florence (Italy); Department of Physics and Astronomy, University of Florence (Italy); Brandi, F.; Carzino, R. [Nanophysics, Istituto Italiano di Tecnologia, Genova (Italy); Citroni, M. [European Laboratory for Non-Linear Spectroscopy, LENS, Florence (Italy); De Sio, A. [Department of Physics and Astronomy, University of Florence (Italy); Fanetti, S. [European Laboratory for Non-Linear Spectroscopy, LENS, Florence (Italy); Lagomarsino, S. [National Institute for Nuclear Physics, INFN, Florence (Italy); Department of Physics and Astronomy, University of Florence (Italy); Pace, E. [Department of Physics and Astronomy, University of Florence (Italy); Parrini, G. [National Institute for Nuclear Physics, INFN, Florence (Italy); Department of Physics and Astronomy, University of Florence (Italy); Passeri, D.; Scorzoni, A.; Servoli, L. [Dipartimento di Ingegneria Elettronica e della Informazione and INFN Sez. Perugia, Perugia (Italy); Tozzetti, L. [Department of Physics and Astronomy, University of Florence (Italy)


    In this work we report preliminary tests aimed at the implementation of a Silicon-On-Diamond (SOD) radiation sensor. SOD materials have been prepared by continuously scanning a 20 ps pulsed 355 nm laser beam on the silicon–diamond interface. A pixel monolithic sensor has also been bonded to diamond with the same technique and tested to show that a complex electronic chip can undergo the process without any damage. Through silicon vias have been fabricated by laser drilling on the silicon side of the SOD samples and their insulation from the silicon bulk has been tested. The charge collection efficiency of a diamond sensor with laser-written graphitic contacts has been measured, to demonstrate a reliable and simple way to fabricate ohmic contacts on the diamond side of the SOD devices. Finally, a SOD material with electric contacts on the silicon and on the diamond sides has been tested as a particle sensor to demonstrate the electrical continuity of the silicon–diamond interface after the bonding. -- Highlights: •The steps necessary to fabricate a monolithic Silicon-On-Diamond detector have been carried out. •These steps involve the bonding, by a laser technique, of an electronic chip on diamond without damage, the growth of insulated Through Silicon Vias in silicon, the fabrication of ohmic contacts by laser graphitization. •In conclusion: the feasibility of a SOD detector with the readout silicon electronics bonded to the diamond sensitive volume has been demonstrated. •Graphitic contacts compare favorably with standard metallic ones. •Charge is collected by a SOD material. That is, the silicon–diamond bonding interface does not prevent charge collection.

  1. A family of compatible single- and multimicroprocessor systems with 8-bit and 16-bit Microprocessors

    Brzezinski, J.; Cellary, W.; Kreglewski, J.


    In the paper, a multimicroprocessor system for 8-bit and 16-bit microprocessors is presented. The main assumptions of the project of the presented system are discussed. Different single- and multimicroprocessor structures with 8-bit microprocessors are outlined. A detailed description of two single-board microcomputers and system aspects of different solutions are presented. Finally, an intelligent floppy disk controller is described.

  2. Diamond Measuring Machine

    Krstulic, J.F.


    The fundamental goal of this project was to develop additional capabilities to the diamond measuring prototype, work out technical difficulties associated with the original device, and perform automated measurements which are accurate and repeatable. For this project, FM and T was responsible for the overall system design, edge extraction, and defect extraction and identification. AccuGem provided a lab and computer equipment in Lawrence, 3D modeling, industry expertise, and sets of diamonds for testing. The system executive software which controls stone positioning, lighting, focusing, report generation, and data acquisition was written in Microsoft Visual Basic 6, while data analysis and modeling were compiled in C/C++ DLLs. All scanning parameters and extracted data are stored in a central database and available for automated analysis and reporting. The Phase 1 study showed that data can be extracted and measured from diamond scans, but most of the information had to be manually extracted. In this Phase 2 project, all data required for geometric modeling and defect identification were automatically extracted and passed to a 3D modeling module for analysis. Algorithms were developed which automatically adjusted both light levels and stone focus positioning for each diamond-under-test. After a diamond is analyzed and measurements are completed, a report is printed for the customer which shows carat weight, summarizes stone geometry information, lists defects and their size, displays a picture of the diamond, and shows a plot of defects on a top view drawing of the stone. Initial emphasis of defect extraction was on identification of feathers, pinpoints, and crystals. Defects were plotted color-coded by industry standards for inclusions (red), blemishes (green), and unknown defects (blue). Diamonds with a wide variety of cut quality, size, and number of defects were tested in the machine. Edge extraction, defect extraction, and modeling code were tested for

  3. Salton Sea Scientific Drilling Project: A summary of drilling and engineering activities and scientific results

    Ross, H.P.; Forsgren, C.K. (eds.)


    The Salton Sea Scientific g Project (SSSDP) completed the first major well in the United States Continental Scientific Drilling Program. The well (State 2-14) was drilled to 10,W ft (3,220 m) in the Salton Sea Geothermal Field in California's Imperial Valley, to permit scientific study of a deep, high-temperature portion of an active geothermal system. The program was designed to investigate, through drilling and testing, the subsurface thermal, chemical, and mineralogical environments of this geothermal area. Extensive samples and data, including cores, cuttings, geothermal fluids and gases, and geophysical logs, were collected for future scientific analysis, interpretation, and publication. Short duration flow tests were conducted on reservoirs at a depth of approximately 6,120 ft (1,865 m) and at 10,136 ft (3,089 m). This report summarizes all major activities of the SSSDP, from project inception in the fall of 1984 through brine-pond cleanup and site restoration, ending in February 1989. This report presents a balanced summary of drilling, coring, logging, and flow-test operations, and a brief summary of technical and scientific results. Frequent reference is made to original records, data, and publication of results. The report also reviews the proposed versus the final well design, and operational summaries, such as the bit record, the casing and cementing program, and the coring program. Summaries are and the results of three flow tests. Several teamed during the project.

  4. Flexible roof drill for low coal. Volume 2. Phase III and Phase IV

    Shoup, N.H.


    Design specifications were developed for a flexible drilling and bolting system. The system configuration is based on the use of the Galis dual-boom roof drill as a vehicle for the drilling/bolting system. The WSU Flex-drill drivehead is mounted on the Galis drill boom and the Galis parts are modified to accommodate the revised system. The flexible drillhead supports a bolt bender/inserter designed by Bendix Corporation and is integrated into the system operation. A supplemental bolt thruster was designed to complete insertion of the roof bolt following operation and removal of the Bendix bender from the bolt shank. The complete cycle of drilling a 1-3/8-in. diameter bolt hole, bending a roof bolt into the hole, thrusting the bolt head and washer to the roof surface, and final torquing of the bolt is manually controlled by the operator located in the new position behind the bolting line. The new operating position is beneath newly bolted roof in a safer location in back of the stab jack ad roof jacks positioning the drill boom and drivehead. The Flex-drill/bolting system prototype was constructed from both purchased components and parts specially fabricated in the shops for this design. This unit was assembled and test-operated with appropriate support equipment in a laboratory test stand. Numerous test holes were drilled in blocks of concrete at feed rates of 5 ft/min with drill rotation speeds of 360 rpm. The drill feeds uniformly and cuts smoothly with no difficulty in collection of dust or clogging of the drill bit. The holes drilled were straight, as evidence by passage of a 1-1/4-in. diameter bar full depth into the hole with no binding or evidence of curvature. The flexible drill is capable of drilling 8-ft-deep roof bolt holes in low coal 36 in. in height.

  5. Modeling of wave propagation in drill strings using vibration transfer matrix methods.

    Han, Je-Heon; Kim, Yong-Joe; Karkoub, Mansour


    In order to understand critical vibration of a drill bit such as stick-slip and bit-bounce and their wave propagation characteristics through a drill string system, it is critical to model the torsional, longitudinal, and flexural waves generated by the drill bit vibration. Here, a modeling method based on a vibration transfer matrix between two sets of structural wave variables at the ends of a constant cross-sectional, hollow, circular pipe is proposed. For a drill string system with multiple pipe sections, the total vibration transfer matrix is calculated by multiplying all individual matrices, each is obtained for an individual pipe section. Since drill string systems are typically extremely long, conventional numerical analysis methods such as a finite element method (FEM) require a large number of meshes, which makes it computationally inefficient to analyze these drill string systems numerically. The proposed "analytical" vibration transfer matrix method requires significantly low computational resources. For the validation of the proposed method, experimental and numerical data are obtained from laboratory experiments and FEM analyses conducted by using a commercial FEM package, ANSYS. It is shown that the modeling results obtained by using the proposed method are well matched with the experimental and numerical results.

  6. Topical review: spins and mechanics in diamond

    Lee, Donghun; Lee, Kenneth W.; Cady, Jeffrey V.; Ovartchaiyapong, Preeti; Bleszynski Jayich, Ania C.


    There has been rapidly growing interest in hybrid quantum devices involving a solid-state spin and a macroscopic mechanical oscillator. Such hybrid devices create exciting opportunities to mediate interactions between disparate quantum bits (qubits) and to explore the quantum regime of macroscopic mechanical objects. In particular, a system consisting of the nitrogen-vacancy defect center (NV center) in diamond coupled to a high-quality-factor mechanical oscillator is an appealing candidate for such a hybrid quantum device, as it utilizes the highly coherent and versatile spin properties of the defect center. In this paper, we will review recent experimental progress on diamond-based hybrid quantum devices in which the spin and orbital dynamics of single defects are driven by the motion of a mechanical oscillator. In addition, we discuss prospective applications for this device, including long-range, phonon-mediated spin–spin interactions, and phonon cooling in the quantum regime. We conclude the review by evaluating the experimental limitations of current devices and identifying alternative device architectures that may reach the strong coupling regime.

  7. Drilling and well technology

    Milheim, K. [Mining University Leoben Institute for Drilling Technology, (Austria)


    Over a billion dollars a year is lost by exploration and production companies drilling wells because of the lack of learn curve management (LMC) practices. This paper presents the importance of the LMC concept, what it is, why LMC has not yet been recognized as a major initiative for improving drilling cost performance. The paper discusses the different types of planning, problems with implementation of plans, the use and misuse of drilling results and data bases, and the lack of post analysis practices. The major point of the paper is to show the massive savings that can be achieved by valuing LMC, learning LMC and successfully implementing LMC. . 2 refs., 5 figs.

  8. 76 FR 11812 - Drill Pipe and Drill Collars From China


    ... Register on September 9, 2010 (75 FR 54912). The hearing was held in Washington, DC, on January 5, 2011... COMMISSION Drill Pipe and Drill Collars From China Determinations On the basis of the record \\1\\ developed in... of imports of drill pipe and drill collars from China, provided for in subheadings 7304.22,...

  9. 75 FR 10501 - Drill Pipe and Drill Collars from China


    ... publishing the notice in the Federal Register of January 6, 2010 (75 FR 877). The conference was held in... COMMISSION Drill Pipe and Drill Collars from China Determinations On the basis of the record \\1\\ developed in... injury by reason of imports from China of drill pipe and drill collars, provided for in subheadings...


    Mera Fayez Horne


    Full Text Available The results from the Phoenix mission led scientists to believe it is possible that primitive life exists below the Martian surface. Therefore, drilling in Martian soil in search for organisms is the next logical step. Drilling on Mars is a major engineering challenge due to the drilling depth requirement and extreme environment condition. Mars lacks a thick atmosphere and a continuous magnetic field that shield the planet’s surface from solar radiation and solar flares. As a result, the Martian surface is sterile and if life ever existed, it must be found below the surface. NASA’s Mars Exploration Payload Advisory Group proposed that drilling should be considered as a priority investigation on Mars in an effort of finding evidence of extinct or extant life. The results from the Curiosity mission suggested drilling six meters deep in the red planet in search for life. Excavation tools deployed to Mars so far have been able to drill to a maximum depth of 6.5 cm. Thus, the drilling capabilities need to be increased by a factor of approximately 100 to achieve the goal of drilling six meters deep. This requirement puts a demand on developing new and more effective technologies to reach this goal. Previous research shows evidence of a promising drilling mechanism in rotary-ultrasonic for what it offers in terms of high surface quality, faster rate of penetration and higher material removal rate. This research addresses the need to understand the mechanics of the drill bit tip and rock interface in rotary-ultrasonic drilling performance of one drill bit at a time drilling in three types of rocks that vary in strength. A mathematical model identifying all contributing independent parameters, such as drill bit design parameters, drilling process parameters, ultrasonic wave amplitude and rocks’ material properties, that have effect on rate of penetration is developed. Analytical and experimental results under ambient condition are presented to show

  11. Optimization of Operating Parameters for Minimum Mechanical Specific Energy in Drilling

    Hamrick, Todd [West Virginia Univ., Morgantown, WV (United States)


    Efficiency in drilling is measured by Mechanical Specific Energy (MSE). MSE is the measure of the amount of energy input required to remove a unit volume of rock, expressed in units of energy input divided by volume removed. It can be expressed mathematically in terms of controllable parameters; Weight on Bit, Torque, Rate of Penetration, and RPM. It is well documented that minimizing MSE by optimizing controllable factors results in maximum Rate of Penetration. Current methods for computing MSE make it possible to minimize MSE in the field only through a trial-and-error process. This work makes it possible to compute the optimum drilling parameters that result in minimum MSE. The parameters that have been traditionally used to compute MSE are interdependent. Mathematical relationships between the parameters were established, and the conventional MSE equation was rewritten in terms of a single parameter, Weight on Bit, establishing a form that can be minimized mathematically. Once the optimum Weight on Bit was determined, the interdependent relationship that Weight on Bit has with Torque and Penetration per Revolution was used to determine optimum values for those parameters for a given drilling situation. The improved method was validated through laboratory experimentation and analysis of published data. Two rock types were subjected to four treatments each, and drilled in a controlled laboratory environment. The method was applied in each case, and the optimum parameters for minimum MSE were computed. The method demonstrated an accurate means to determine optimum drilling parameters of Weight on Bit, Torque, and Penetration per Revolution. A unique application of micro-cracking is also presented, which demonstrates that rock failure ahead of the bit is related to axial force more than to rotation speed.

  12. Drilling and Completion of the Urach III HDR Test Well

    Meier, U.; Ernst, P. L.


    The hot dry rock (HDR) test well, urach III, was drilled and completed in 1979. The borehole is located in Southwest Germany in the geothermal anomaly of Urach. The purpose of project Urach was to study drilling and completion problems of HDR wells and to provide a test site for a HDR research program. The Urach III borehole was drilled to a total depth of 3,334 meters (10,939 feet), penetrating 1,700 meters (5,578 feet) into the granitic basement. Extensive coring was required to provide samples for geophysical and geochemical studies. Positive displacement downhole motors were used for coring and normal drilling operations. It was found that these motors in combination with the proper bits gave better results than conventional rotary drilling. Loss of circulation was encountered not only in sedimentary rocks but also in the granite. After drilling and completion of the borehole, a number of hydraulic fracturing experiments were performed in the open hole as well as in the cased section of Urach III. A circulation loop was established by using the single-borehole concept. It is not yet clear whether new fractures have actually been generated or preexisting joints and fissures have been reactivated. Evaluation of the results of this first step is almost completed and the planning of Phase II of the Urach project is under way.

  13. Mechanically induced degradation of diamond

    Bouwelen, F V


    bombardment a mechanically induced graphitisation, as opposed to a thermally activated transformation, may occur locally on collision with the CVD diamond. Two types of diamond-graphite interfaces were observed: (111) planes of diamond parallel to the a-b planes of graphite and (111) planes of diamond, smoothly within the plane, connected to a-b planes of graphite. The thesis concludes with a summary of the results, conclusions and recommendations for further work. This thesis deals with the wear of diamond occurring during frictional sliding contact between diamonds. In the introduction, a literature survey on friction, wear and polishing behaviour of diamond, with some emphasis on the anisotropy, is presented and earlier work is discussed. A review of the existing theories is given, a new hypothesis is proposed and key-experiments for verification are identified. Electron microscopical techniques such as High Resolution Electron Microscopy (HREM) imaging and Electron Energy Loss Spectroscopy are described a...


    Mihai ISPAS


    Full Text Available Pre-laminated (coated particleboards (PB are wood-based composites intensively used in the furniture industry. In order to prepare the PB for joining, drilling is the most commonly applied machining process. The surface quality and the dynamic parameters (thrust force and torque are significantly influenced by the tools characteristics and the machining parameters. The point/tip angle of the drill bit and the feed speed during drilling play a major role in gaining a good surface quality and minimizing the dynamic parameters. The objective of this study was to measure and analyze the influence of both the geometric and cinematic parameters on the dynamic parameters at drilling with twist (helical drills. The experiments were performed based on a factorial design. The results show that, a low feed rate generally minimizes both the drilling torque and the thrust force, while a small tip angle increases the drilling torque and minimizes the thrust force.

  15. Voice Coil Percussive Mechanism Concept for Hammer Drill

    Okon, Avi


    A hammer drill design of a voice coil linear actuator, spring, linear bearings, and a hammer head was proposed. The voice coil actuator moves the hammer head to produce impact to the end of the drill bit. The spring is used to store energy on the retraction and to capture the rebound energy after each impact for use in the next impact. The maximum actuator stroke is 20 mm with the hammer mass being 200 grams. This unit can create impact energy of 0.4 J with 0.8 J being the maximum. This mechanism is less complex than previous devices meant for the same task, so it has less mass and less volume. Its impact rate and energy are easily tunable without changing major hardware components. The drill can be driven by two half-bridges. Heat is removed from the voice coil via CO2 conduction.

  16. Drilling analysis of coir–fibre-reinforced polyester composites

    S Jayabal; U Natarajan


    An investigation has been carried out to make use of coir, a natural fibre abundantly available in India. Coir–polyester composites were prepared and their mechanical and machinability characteristics were studied. The short coir–fibre-reinforced composites exhibited the tensile, flexural and impact strength of 16.1709 MPa, 29.2611 MPa and 46.1740 J/m, respectively. The regression equations were developed and optimized for studying drilling characteristics of coir–polyester composites using the Taguchi approach. A drill bit diameter of 6 mm, spindle speed of 600 rpm and feed rate of 0.3 mm/rev gave the minimum value of thrust force, torque and tool wear in drilling analysis.

  17. Large scale fabrication of nitrogen vacancy-embedded diamond nanostructures for single-photon source applications

    Jiang, Qianqing; Li, Wuxia; Tang, Chengchun; Chang, Yanchun; Hao, Tingting; Pan, Xinyu; Ye, Haitao; Li, Junjie; Gu, Changzhi


    Some color centers in diamond can serve as quantum bits which can be manipulated with microwave pulses and read out with laser, even at room temperature. However, the photon collection efficiency of bulk diamond is greatly reduced by refraction at the diamond/air interface. To address this issue, we fabricated arrays of diamond nanostructures, differing in both diameter and top end shape, with HSQ and Cr as the etching mask materials, aiming toward large scale fabrication of single-photon sources with enhanced collection efficiency made of nitrogen vacancy (NV) embedded diamond. With a mixture of O2 and CHF3 gas plasma, diamond pillars with diameters down to 45 nm were obtained. The top end shape evolution has been represented with a simple model. The tests of size dependent single-photon properties confirmed an improved single-photon collection efficiency enhancement, larger than tenfold, and a mild decrease of decoherence time with decreasing pillar diameter was observed as expected. These results provide useful information for future applications of nanostructured diamond as a single-photon source. Project supported by the National Key Research and Development Plan of China (Grant No. 2016YFA0200402), the National Natural Science Foundation of China (Grants Nos. 11574369, 11574368, 91323304, 11174362, and 51272278), and the FP7 Marie Curie Action (project No. 295208) sponsored by the European Commission.

  18. CVD diamond - fundamental phenomena

    Yarbrough, W.A. [Pennsylvania State Univ., University Park (United States)


    This compilation of figures and diagrams addresses the basic physical processes involved in the chemical vapor deposition of diamond. Different methods of deposition are illustrated. For each method, observations are made of the prominent advantages and disadvantages of the technique. Chemical mechanisms of nucleation are introduced.

  19. Biofunctionalization of diamond microelectrodes

    Reitinger, Andreas Adam; Lud, Simon Quartus; Stutzmann, Martin; Garrido, Jose Antonio [Walter Schottky Institut, TU Muenchen (Germany); Hutter, Naima Aurelia; Richter, Gerhard; Jordan, Rainer [WACKER-Chair of Macromolecular Chemistry, TU Muenchen (Germany)


    In this work we present two main routes for the biofunctionalization of nanocrystalline diamond films, aiming at the application of diamond microelectrodes as amperometric biosensors. We report on direct covalent grafting of biomolecules on nanocrystalline diamond films via diazonium monophenyls and biphenyls as well as other linker molecules, forming self-assembled monolayers on the diamond surface. Monolayers with different functional head groups have been characterized. Patterning of the available functional groups using electron beam-induced chemical lithography allows the selective preparation of well-localized docking sites for the immobilization of biomolecules. Furthermore, polymer brushes are expected to enable novel paths for designing more advanced biosensing schemes, incorporating multifunctional groups and a higher loading capacity for biomolecules. Here, we focus on the preparation of polymer grafts by self-initiated photografting and photopolymerization. Further chemical modification of the grafted polymer brushes results in the introduction of additional functional molecules, paving the way for the incorporation of more complex molecular structures such as proteins. In a comparative study we investigate the advantages and disadvantages of both approaches.

  20. Nonpolluting drilling fluid composition

    Larson, D.E.; Mocek, C.J.; Mouton, R.J.


    Disclosed is a nonpolluting drilling fluid composition. The composition mixture consisting essentially of a concentrate and any nonpolluting oil. The concentrate consists essentially of diethanolamide, a fatty acid, and a imidazoline/amide mixture.

  1. Diamond growth in mantle fluids

    Bureau, Hélène; Frost, Daniel J.; Bolfan-Casanova, Nathalie; Leroy, Clémence; Esteve, Imène; Cordier, Patrick


    In the upper mantle, diamonds can potentially grow from various forms of media (solid, gas, fluid) with a range of compositions (e.g. graphite, C-O-H fluids, silicate or carbonate melts). Inclusions trapped in diamonds are one of the few diagnostic tools that can constrain diamond growth conditions in the Earth's mantle. In this study, inclusion-bearing diamonds have been synthesized to understand the growth conditions of natural diamonds in the upper mantle. Diamonds containing syngenetic inclusions were synthesized in multi-anvil presses employing starting mixtures of carbonates, and silicate compositions in the presence of pure water and saline fluids (H2O-NaCl). Experiments were performed at conditions compatible with the Earth's geotherm (7 GPa, 1300-1400 °C). Results show that within the timescale of the experiments (6 to 30 h) diamond growth occurs if water and carbonates are present in the fluid phase. Water promotes faster diamond growth (up to 14 mm/year at 1400 °C, 7 GPa, 10 g/l NaCl), which is favorable to the inclusion trapping process. At 7 GPa, temperature and fluid composition are the main factors controlling diamond growth. In these experiments, diamonds grew in the presence of two fluids: an aqueous fluid and a hydrous silicate melt. The carbon source for diamond growth must be carbonate (CO32) dissolved in the melt or carbon dioxide species in the aqueous fluid (CO2aq). The presence of NaCl affects the growth kinetics but is not a prerequisite for inclusion-bearing diamond formation. The presence of small discrete or isolated volumes of water-rich fluids is necessary to grow inclusion-bearing peridotitic, eclogitic, fibrous, cloudy and coated diamonds, and may also be involved in the growth of ultradeep, ultrahigh-pressure metamorphic diamonds.

  2. Wireless Network Simplification: the Gaussian N-Relay Diamond Network

    Nazaroglu, Caner; Fragouli, Christina


    We consider the Gaussian N-relay diamond network, where a source wants to communicate to a destination node through a layer of N-relay nodes. We investigate the following question: What fraction of the capacity can we maintain by using only k out of the N available relays? We show that in every Gaussian N-relay diamond network, there exists a subset of k relays which alone provide approximately a fraction k/(k+1) of the total capacity. The result holds independent of the number of available relay nodes N, the channel configurations and the operating SNR. The result is tight in the sense that there exists channel configurations for N-relay diamond networks, where every subset of k relays can provide at most a fraction of k/(k+1) of the total capacity. The approximation is within 3logN+3k bits/s/Hz to the capacity. This result also provides a new approximation to the capacity of the Gaussian N-relay diamond network which is up to a multiplicative gap of 1/(k+1) and additive gap of 3logN+3k. The current approxim...


    Lanny Sutanto


    Full Text Available The rapid development of the Internet today to easily exchange data. This leads to high levels of risk in the data piracy. One of the ways to secure data is using cryptography camellia. Camellia is known as a method that has the encryption and decryption time is fast. Camellia method has three kinds of scale key is 128 bit, 192 bit, and 256 bit.This application is created using the C++ programming language and using visual studio 2010 GUI. This research compare the smallest and largest key size used on the file extension .Txt, .Doc, .Docx, .Jpg, .Mp4, .Mkv and .Flv. This application is made to comparing time and level of security in the use of 128-bit key and 256 bits. The comparison is done by comparing the results of the security value of avalanche effect 128 bit key and 256 bit key.

  4. Continental Scientific Drilling Program.


    Resource Priorities in Continental Drilling J. J. Hemley 12 Aspects of Continental Crustal Structure and Growth Scott Smithson 13 Deep-Drilling Targets...Time of Workshop Allen F. Agnew Library of Congress Clarence R. Allen California Institute of Technology Orson L. Anderson University of California at...Skinner Yale University Norman H. Sleep Northwestern University Laurence L. Sloss Northwestern University Scott B. Smithson University of Wyoming

  5. Growth of borehole breakouts with time after drilling: Implications for state of stress, NanTroSEIZE transect, SW Japan

    Moore, J. Casey; Chang, Chandong; Mcneill, Lisa; Thu, Moe Kyaw; Yamada, Yasuhiro; Huftile, Gary


    Resistivity at the bit tools typically provide images of wellbore breakouts only a few minutes after the hole is drilled. In certain cases images are taken tens of minutes to days after drilling of the borehole. The sonic caliper can also image borehole geometry. We present four examples comparing imaging a few minutes after drilling to imaging from about 30 min to 3 days after drilling. In all cases the borehole breakouts widen with time. The tendency to widen with time is most pronounced wi...

  6. Study of the influences of rotary table speed on stick-slip vibration of the drilling system

    Liping Tang


    Full Text Available Stick-slip vibration presents one of the major causes of drilling problems, such as premature tool failures, low drilling efficiency and poor wellbore quality. The objective of this work is to investigate the influences of rotary table speed (RTS on stick-slip phenomenon of the drilling system. In this study, the drilling system is treated as a lumped torsional pendulum model of which the bit/rock interaction is regarded as Coulomb friction. By analyzing cases with different RTS, two types of vibrations on the bit are found: stick-slip vibration and uniform motion. With an increase in the RTS, the stick-slip vibration on the drill bit disappears once the RTS arrives at its critical value. For the cases that stick-slip vibrations occur, the phase trajectories converge toward a limit cycle. For the cases that stick-slip vibration does not appear, the drill bit tends to stabilize at a uniform motion and the phase trajectories correspond to contracting spirals observed in the phase plane.

  7. A predictive bone drilling force model for haptic rendering with experimental validation using fresh cadaveric bone.

    Lin, Yanping; Chen, Huajiang; Yu, Dedong; Zhang, Ying; Yuan, Wen


    Bone drilling simulators with virtual and haptic feedback provide a safe, cost-effective and repeatable alternative to traditional surgical training methods. To develop such a simulator, accurate haptic rendering based on a force model is required to feedback bone drilling forces based on user input. Current predictive bone drilling force models based on bovine bones with various drilling conditions and parameters are not representative of the bone drilling process in bone surgery. The objective of this study was to provide a bone drilling force model for haptic rendering based on calibration and validation experiments in fresh cadaveric bones with different bone densities. Using a commonly used drill bit geometry (2 mm diameter), feed rates (20-60 mm/min) and spindle speeds (4000-6000 rpm) in orthognathic surgeries, the bone drilling forces of specimens from two groups were measured and the calibration coefficients of the specific normal and frictional pressures were determined. The comparison of the predicted forces and the measured forces from validation experiments with a large range of feed rates and spindle speeds demonstrates that the proposed bone drilling forces can predict the trends and average forces well. The presented bone drilling force model can be used for haptic rendering in surgical simulators.

  8. Bit-string scattering theory

    Noyes, H.P.


    We construct discrete space-time coordinates separated by the Lorentz-invariant intervals h/mc in space and h/mc{sup 2} in time using discrimination (XOR) between pairs of independently generated bit-strings; we prove that if this space is homogeneous and isotropic, it can have only 1, 2 or 3 spacial dimensions once we have related time to a global ordering operator. On this space we construct exact combinatorial expressions for free particle wave functions taking proper account of the interference between indistinguishable alternative paths created by the construction. Because the end-points of the paths are fixed, they specify completed processes; our wave functions are born collapsed''. A convenient way to represent this model is in terms of complex amplitudes whose squares give the probability for a particular set of observable processes to be completed. For distances much greater than h/mc and times much greater than h/mc{sup 2} our wave functions can be approximated by solutions of the free particle Dirac and Klein-Gordon equations. Using a eight-counter paradigm we relate this construction to scattering experiments involving four distinguishable particles, and indicate how this can be used to calculate electromagnetic and weak scattering processes. We derive a non-perturbative formula relating relativistic bound and resonant state energies to mass ratios and coupling constants, equivalent to our earlier derivation of the Bohr relativistic formula for hydrogen. Using the Fermi-Yang model of the pion as a relativistic bound state containing a nucleon-antinucleon pair, we find that (G{sub {pi}N}{sup 2}){sup 2} = (2m{sub N}/m{sub {pi}}){sup 2} {minus} 1. 21 refs., 1 fig.

  9. Forty years of development in diamond tools

    The growth of the diamond industry in Western Countries since the First World War is surveyed. The articles described deal specifically with the development of the industrial diamond and diamond tool sector in different countries. All data point to continuing rapid expansion in the diamond tool sector. The West consumes 80 percent of world industrial diamond production. Diamond consumption increased sharply in the U.S. during World War 2. There are 300 diamond manufacturers in the U.S. today. In 1940, there were 25. In Japan, consumption of industrial diamonds has increased several times. In Italy, there has been a 75 fold increase in the production of diamond tools since 1959.

  10. Paramagnetism shielding in drilling fluid



    In drilling operations, drilling fluid containing magnetic materials is used when drilling a well. The materials can significantly shield the Earth’s magnetic field as measured by magnetic sensors inside the drilling strings. The magnetic property of the drilling fluid is one of the substantial error sources for the determination of magnetic azimuth for wellbores. Both the weight material, cuttings, clay and other formation material plus metal filings from the tubular wear m...

  11. Pixel detector system development at Diamond Light Source

    Marchal, J.; Horswell, I.; Gimenez, E. N.; Tartoni, N.


    Hybrid pixel detectors consisting of an array of silicon photodiodes bump-bonded to CMOS read-out chips provide high signal-to-noise ratio and high dynamic range compared to CCD-based detectors and Image Plates. These detector features are important for SAXS experiments where a wide range of intensities are present in the images. For time resolved SAXS experiments, high frame rates are compulsory. The latest CMOS read-out chip developed by the MEDIPIX collaboration provides high frame rate and continuous acquisition mode. A read-out system for an array of MEDIPIX3 sensors is under development at Diamond Light Source. This system will support a full resolution frame rate of 1 kHz at a pixel counter depth of 12-bit and a frame rate of 30 kHz at a counter depth of 1 bit. Details concerning system design and MEDIPIX sensors characterization are presented.

  12. A holistic approach to bit preservation

    Zierau, Eld


    Purpose: The purpose of this paper is to point out the importance of taking a holistic approach to bit preservation when setting out to find an optimal bit preservation solution for specific digital materials. In the last decade there has been an increasing awareness that bit preservation, which...... preservation strategies as well as pointing to how such strategies can be evaluated. Research limitations/implications The operational results described here are still missing work to be fully operational. However, the holistic approach is in itself an important result. Furthermore, in spite...

  13. Application on drilling parameter monitor in drilling engineering monitoring

    Shu DIAO; Zhenbao LING; Wenjing LIANG


    The drilling parameter monitor is an important tool in drilling engineering applied to monitoring drilling process, carrying out scientific analysis and decision-making. Based on discussing the present development situation of the domestic and foreign drilling machine parameter monitors, the metering scheme for vehicle-loaded drilling parameter monitor was designed. By using detection system for MSP430 single-chip microcomputer (SCM) in combination with peripheral circuit such as sensors, the drilling-rig control system was obtained to detect, and for every parameter in real-time display in order to keep operating the drilling rig status. The experiment shows that the drilling parameter monitor reaches design requirements and can be applied to drilling engineering monitoring, which has characters such as simple structure, high credibility and low cost.

  14. Conversion of an 8-bit to a 16-bit Soft-core RISC Processor

    Ahmad Jamal Salim


    Full Text Available The demand for 8-bit processors nowadays is still going strong despite efforts by manufacturers in producing higher end microcontroller solutions to the mass market. Low-end processor offers a simple, low-cost and fast solution especially on I/O applications development in embedded system. However, due to architectural constraint, complex calculation could not be performed efficiently on 8-bit processor. This paper presents the conversion method from an 8-bit to a 16-bit Reduced Instruction Set Computer (RISC processor in a soft-core reconfigurable platform in order to extend its capability in handling larger data sets thus enabling intensive calculations process. While the conversion expands the data bus width to 16-bit, it also maintained the simple architecture design of an 8-bit processor.The expansion also provides more room for improvement to the processor’s performance. The modified architecture is successfully simulated in CPUSim together with its new instruction set architecture (ISA. Xilinx Virtex-6 platform is utilized to execute and verified the architecture. Results show that the modified 16-bit RISC architecture only required 17% more register slice on Field Programmable Gate Array (FPGA implementation which is a slight increase compared to the original 8-bit RISC architecture. A test program containing instruction sets that handle 16-bit data are also simulated and verified. As the 16-bit architecture is described as a soft-core, further modifications could be performed in order to customize the architecture to suit any specific applications.

  15. Experimental and analytical investigation of the thermal necrosis in high-speed drilling of bone.

    Shakouri, Ehsan; Sadeghi, Mohammad H; Maerefat, Mehdi; Shajari, Shaghayegh


    Bone loss due to thermo necrosis may weaken the purchase of surgically placed screws and pins, causing them to loosen postoperatively. The heat generated during the bone drilling is proportional to cutting speed and force and may be partially dissipated by the blood and tissue fluids, and somehow carried away by the chips formed. Increasing cutting speed will reduce cutting force and machining time. Therefore, it is of interest to study the effects of the increasing cutting speed on bone drilling characteristics. In this article, the effects of the increasing cutting speed ranging from 500 up to 18,000 r/min on the thrust force and the temperature rise are studied for bovine femur bone. The results of this study reveal that the high-speed drilling of 6000-7000 r/min may effectively reduce the two parameters of maximum cortical temperature and duration of exposure at temperatures above the allowable levels, which in turn reduce the probability of thermal necrosis in the drill site. This is due to the reduction of the cutting force and the increase in the chip disposal speed. However, more increases in the drill bit rotational speed result in an increase in the amount of temperature elevation, not because of sensible change in drilling force but a considerable increase in friction among the chips, drill bit and the hole walls.

  16. Self-sharpening-effect of nickel-diamond coatings sprayed by HVOF

    Tillmann, W.; Brinkhoff, A.; Schaak, C.; Zajaczkowski, J.


    The durability of stone working and drilling tools is an increasingly significant requirement in industrial applications. These tools are mainly produced by brazing diamond metal matrix composites inserts to the tool body. These inserts are produced by sintering diamonds and metal powder (e.g. nickel). If the wear is too high, the diamonds will break out of the metal matrix and other diamonds will be uncovered. This effect is called self-sharpening. But diamonds are difficult to handle because of their thermal sensitivity. Due to their high thermal influence, manufacturing costs, and complicate route of manufacturing (first sintering, then brazing), there is a great need for alternative production methods for such tools. One alternative to produce wear-resistant and self-sharpening coatings are thermal spray processes as examined in this paper. An advantage of thermal spray processes is their smaller thermal influence on the diamond, due to the short dwelling time in the flame. To reduce the thermal influence during spraying, nickel coated diamonds were used in the HVOF-process (high velocity oxygen fuel process). The wear resistance was subsequently investigated by means of a standardized ball-on-disc test. Furthermore, a SEM (scanning electron microscope) was used to gain information about the wear-mechanism and the self-sharpening effect of the coating.

  17. Combining conventional and thermal drilling in order to increase speed and reduce costs of drilling operations to access deep geothermal resources

    Rossi, Edoardo; Kant, Michael A.; von Rohr, Philipp Rudolf; Saar, Martin O.


    The exploitation of deep geothermal resources for energy production relies on finding cost effective solutions to increase the drilling performance in hard rocks. Conventional rotary drilling techniques, based on mechanical rock exportation, result in high rates of drilling tool wearing, causing significant costs. Additionally, rotary drilling results in low drilling speeds in the typically hard crystalline basement rocks targeted for enhanced geothermal energy utilization technologies. Furthermore, even lower overall drilling rates result, when considering tripping times required to exchange worn drill tools. Therefore, alternative drilling techniques, such as hammering, thermal drilling, plasma drilling, and jetting processes are widely investigated in order to provide cost-effective alternatives to conventional drilling methods. A promising approach, that combines conventional rotary and thermal drilling techniques, is investigated in the present work. Here, the rock material is thermally weakened before being exported by conventional cutters. Heat is locally provided by a flame, which moves over the rock surface, heat-treating the material. Besides reducing the rock strength, an in-depth smoothening effect of the mechanical rock properties is observed due to the thermal treatment. This results in reduced rates of drill bit wearing and higher rates of penetration, which in turn decreases drilling costs significantly, particularly for deep-drilling projects. Due to the high heating rates, rock-hardening, commonly observed at moderate temperatures, can be avoided. The flame action can be modelled as a localized, high heat transfer coefficient flame treatment, which results in orders of magnitude higher heating rates than conventional oven treatments. Therefore, we analyse rock strength variations after different maximum temperatures, flame-based heating rates, and rock confinement pressures. The results show that flame treatments lead to a monotonous decrease of

  18. Trial to active seismic while drilling; Jinko shingen wo mochiita SWD eno kokoromi

    Tsuru, T.; Kozawa, T. [Japan National Oil Corp., Tokyo (Japan). Technology Research Center


    This paper describes the development of a more stable SWD system with larger energy by adding an artificial seismic source near the bit. SWD is a technique by which the seismic wave generated while drilling of rocks by bit can be observed on the ground surface and the records equivalent to the reverse VSP can be obtained. For this system, a shell with a vibrator was fixed immediately on the bit as a sub-generator, and total energy of usual impact by the bit and vibration by the vibrator was used as a seismic source for SWD. For the seismic wave generation mechanism of this vibrator, the shell was resonated by the magnetostrictive element, and vibration was given to the bit and drilling pipe. When this seismic source is used, only single frequency is obtained for each vibration due to the utilization of resonance of shell. Therefore, the generation patterns should be made, by which wide band energy can be obtained after the interaction. Since the survey was conducted using this bottom hole seismic source at the drilling depth more than 3,000 m, it was necessary to enhance the vibration energy. 2 refs., 2 figs.

  19. Structure and properties of diamond and diamond-like films

    Clausing, R.E. [Oak Ridge National Lab., TN (United States)


    This section is broken into four parts: (1) introduction, (2) natural IIa diamond, (3) importance of structure and composition, and (4) control of structure and properties. Conclusions of this discussion are that properties of chemical vapor deposited diamond films can compare favorably with natural diamond, that properties are anisotropic and are a strong function of structure and crystal perfection, that crystal perfection and morphology are functions of growth conditions and can be controlled, and that the manipulation of texture and thereby surface morphology and internal crystal perfection is an important step in optimizing chemically deposited diamond films for applications.

  20. FastBit: Interactively Searching Massive Data

    Wu, Kesheng; Ahern, Sean; Bethel, E. Wes; Chen, Jacqueline; Childs, Hank; Cormier-Michel, Estelle; Geddes, Cameron; Gu, Junmin; Hagen, Hans; Hamann, Bernd; Koegler, Wendy; Lauret, Jerome; Meredith, Jeremy; Messmer, Peter; Otoo, Ekow; Perevoztchikov, Victor; Poskanzer, Arthur; Prabhat,; Rubel, Oliver; Shoshani, Arie; Sim, Alexander; Stockinger, Kurt; Weber, Gunther; Zhang, Wei-Ming


    As scientific instruments and computer simulations produce more and more data, the task of locating the essential information to gain insight becomes increasingly difficult. FastBit is an efficient software tool to address this challenge. In this article, we present a summary of the key underlying technologies, namely bitmap compression, encoding, and binning. Together these techniques enable FastBit to answer structured (SQL) queries orders of magnitude faster than popular database systems. To illustrate how FastBit is used in applications, we present three examples involving a high-energy physics experiment, a combustion simulation, and an accelerator simulation. In each case, FastBit significantly reduces the response time and enables interactive exploration on terabytes of data.

  1. An optical ultrafast random bit generator

    Kanter, Ido; Aviad, Yaara; Reidler, Igor; Cohen, Elad; Rosenbluh, Michael


    The generation of random bit sequences based on non-deterministic physical mechanisms is of paramount importance for cryptography and secure communications. High data rates also require extremely fast generation rates and robustness to external perturbations. Physical generators based on stochastic noise sources have been limited in bandwidth to ~100 Mbit s-1 generation rates. We present a physical random bit generator, based on a chaotic semiconductor laser, having time-delayed self-feedback, which operates reliably at rates up to 300 Gbit s-1. The method uses a high derivative of the digitized chaotic laser intensity and generates the random sequence by retaining a number of the least significant bits of the high derivative value. The method is insensitive to laser operational parameters and eliminates the necessity for all external constraints such as incommensurate sampling rates and laser external cavity round trip time. The randomness of long bit strings is verified by standard statistical tests.

  2. Bit Loading Algorithms for Cooperative OFDM Systems

    Bo Gui


    Full Text Available We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  3. Bit Loading Algorithms for Cooperative OFDM Systems

    Gui Bo


    Full Text Available Abstract We investigate the resource allocation problem for an OFDM cooperative network with a single source-destination pair and multiple relays. Assuming knowledge of the instantaneous channel gains for all links in the entire network, we propose several bit and power allocation schemes aiming at minimizing the total transmission power under a target rate constraint. First, an optimal and efficient bit loading algorithm is proposed when the relay node uses the same subchannel to relay the information transmitted by the source node. To further improve the performance gain, subchannel permutation, in which the subchannels are reallocated at relay nodes, is considered. An optimal subchannel permutation algorithm is first proposed and then an efficient suboptimal algorithm is considered to achieve a better complexity-performance tradeoff. A distributed bit loading algorithm is also proposed for ad hoc networks. Simulation results show that significant performance gains can be achieved by the proposed bit loading algorithms, especially when subchannel permutation is employed.

  4. Horizontal Directional Drilling (HDD) Technology and Applications

    J. G. Cai; X. N. Wang


    @@ 1 What is Horizontal Directional Drilling? Horizontal Directional Drilling, accurately steered drilling, has become state -of- the -art drilling technique in the world. Specially- designed directionsteerable corebarrel and accurate direction measurement tool are available for the use together with wire line core drilling machine. That makes it feasible to extract cores and to measure the drill travel line &length while drilling in a curve.

  5. The Braid-Based Bit Commitment Protocol

    WANG Li-cheng; CAO Zhen-fu; CAO Feng; QIAN Hai-feng


    With recent advances of quantum computation, new threats have closed in upon to the classical public key cryptosystems. In order to build more secure bit commitment schemes, this paper gave a survey of the new coming braid-based cryptography and then brought forward the first braid-based bit commitment protocol. The security proof manifests that the proposed protocol is computationally binding and information-theoretically hiding.Furthermore, the proposed protocol is also invulnerable to currently known quantum attacks.

  6. Evacuation drill at CMS

    Niels Dupont-Sagorin and Christoph Schaefer


    Training personnel, including evacuation guides and shifters, checking procedures, improving collaboration with the CERN Fire Brigade: the first real-life evacuation drill at CMS took place on Friday 3 February from 12p.m. to 3p.m. in the two caverns located at Point 5 of the LHC.   CERN personnel during the evacuation drill at CMS. Evacuation drills are required by law and have to be organized periodically in all areas of CERN, both above and below ground. The last drill at CMS, which took place in June 2007, revealed some desiderata, most notably the need for a public address system. With this equipment in place, it is now possible to broadcast audio messages from the CMS control room to the underground areas.   The CMS Technical Coordination Team and the GLIMOS have focused particularly on preparing collaborators for emergency situations by providing training and organizing regular safety drills with the HSE Unit and the CERN Fire Brigade. This Friday, the practical traini...

  7. Chinese Drilling Crews Active Worldwide


    @@ China Great Wall Drilling Company signed a US$5 million contract with Tunis Joint Venture Petroleum Company in late April for drilling five wells in the middle coastal area of Tunis. This is the first time Tunis has invited the tenders from foreign companies for a drilling project. The participants in the bidding include other 11 drilling companies from the United States, Australia, Croatia and other countries. The drilling operation is expected to start from June this year. Founded in 1995, Great Wall Drilling Company is a subsidiary of CNPC International Engineering Company. The drilling company is now operating more than 50 Chinesemade drilling rigs overseas and involved in the drilling projects in 15 countries and regions such as Sudan, Iran, Indonesia, Egypt, Canada, Kazakhstan,Venezuela and other countries. The Tunis project is the 15th one of the company.

  8. Genetics Home Reference: Diamond-Blackfan anemia

    ... Home Health Conditions Diamond-Blackfan anemia Diamond-Blackfan anemia Printable PDF Open All Close All Enable Javascript ... view the expand/collapse boxes. Description Diamond-Blackfan anemia is a disorder of the bone marrow . The ...

  9. Nanocrystalline diamond films for biomedical applications

    Pennisi, Cristian Pablo; Alcaide, Maria


    Nanocrystalline diamond films, which comprise the so called nanocrystalline diamond (NCD) and ultrananocrystalline diamond (UNCD), represent a class of biomaterials possessing outstanding mechanical, tribological, and electrical properties, which include high surface smoothness, high corrosion re...

  10. Neural network implementation using bit streams.

    Patel, Nitish D; Nguang, Sing Kiong; Coghill, George G


    A new method for the parallel hardware implementation of artificial neural networks (ANNs) using digital techniques is presented. Signals are represented using uniformly weighted single-bit streams. Techniques for generating bit streams from analog or multibit inputs are also presented. This single-bit representation offers significant advantages over multibit representations since they mitigate the fan-in and fan-out issues which are typical to distributed systems. To process these bit streams using ANNs concepts, functional elements which perform summing, scaling, and squashing have been implemented. These elements are modular and have been designed such that they can be easily interconnected. Two new architectures which act as monotonically increasing differentiable nonlinear squashing functions have also been presented. Using these functional elements, a multilayer perceptron (MLP) can be easily constructed. Two examples successfully demonstrate the use of bit streams in the implementation of ANNs. Since every functional element is individually instantiated, the implementation is genuinely parallel. The results clearly show that this bit-stream technique is viable for the hardware implementation of a variety of distributed systems and for ANNs in particular.

  11. Biological applications of nanocrystalline diamond

    Williams, Oliver; Daenen, Michael; Haenen, Ken


    Nanocrystalline diamond films have generated substantial interest in recent years due to their low cost, extreme properties and wide application arena. Diamond is chemically inert, has a wide electrochemical window and is stable in numerous harsh environments. Nanocrystalline diamond has the advantage of being readily grown on a variety of substrates at very low thickness, resulting in smooth conformal coatings with high transparency. These films can be doped from highly insulating to metalli...

  12. Study on a New Steering Mechanism for Point-the-Bit Rotary Steerable System

    Yuanzhi Li


    Full Text Available This paper presents a novel steering mechanism embedded in a point-the-bit rotary steerable system (RSS for oilfield exploitation. The new steering mechanism adopts a set of universal joints to alleviate the high alternative strain on drilling mandrel and employs a specially designed planetary gear small tooth number difference (PGSTD to achieve directional steering. Its principle and characteristics are explained and examined through a series of analyses. First, the eccentric displacement vector of the offset point on the drilling mandrel is formulated and kinematic solutions are established. Next, structural design for the new steering mechanism is addressed. Then, procedures and program architectures for simulating offset state of the drilling mandrel and motion trajectory of the whole steering mechanism are presented. After that, steering motion simulations of the new steering mechanism for both 2D and 3D well trajectories are then performed by combining LabVIEW and SolidWorks. Finally, experiments on the steering motion control of the new steering mechanism prototype are carried out. The simulations and experiments reveal that the steering performance of the new steering mechanism is satisfied. The research can provide good guidance for further research and engineering application of the point-the-bit RSS.

  13. Diamond turning of glass

    Blackley, W.S.; Scattergood, R.O.


    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  14. Ship Heave Effects on ODP Drilling Dynamics: analysis of MWD data in the Nankai Trough

    Myers, G.; Gaillot, P.; Goldberg, D.


    Characterization of the dynamics of ship heave and its effect on downhole drilling and coring has been long sought after in the Ocean Drilling Program. Operating in the Nankai trough region, the JOIDES Resolution acquired new data of downhole parameters using commercially-available Measurement-While-Drilling (MWD) tools at two drilling sites. Our objective during ODP Leg 196 was to record weight-on-bit, rate of penetration, torque, and pump pressure near the bit as drilling proceeded. Digital instruments installed on the rig floor simultaneously acquired vital surface information of the drilling parameters. Although the sampling rate afforded by the downhole tools is insufficient to resolve wave periods of 8-10 seconds, longer wavelength changes are clearly observed. Wavelet transform analysis was used to eliminate window length restrictions with conventional Fourier analysis and to retain the time-specific information recorded in the raw signal. The integration of the uphole and downhole data sets and subsequent wavelet analysis show less variation with heave than in previous experiments near Antarctica where sea states reached 4 meters. The ratio of surface to downhole weight-on-bit for the two data sets in the >30 second spectral window varies systematically with changes in sea state, water depth, pipe depth and driller input. We are thus able to study the effects and drilling dynamics in changing sea states and in water depths up to 4800 meters and to evaluate the operation of the shipboard heave compensation systems. As a result of these analyses, ODP is deriving an empirical approach for operational use to describe downhole and uphole drilling parameters under a variety of conditions and in different geological environments.

  15. Superconductivity in CVD diamond films.

    Takano, Yoshihiko


    A beautiful jewel of diamond is insulator. However, boron doping can induce semiconductive, metallic and superconducting properties in diamond. When the boron concentration is tuned over 3 × 10(20) cm(-3), diamonds enter the metallic region and show superconductivity at low temperatures. The metal-insulator transition and superconductivity are analyzed using ARPES, XAS, NMR, IXS, transport and magnetic measurements and so on. This review elucidates the physical properties and mechanism of diamond superconductor as a special superconductivity that occurs in semiconductors.

  16. Computer monitors drilling performance


    Computer systems that can monitor over 40 drilling variables, display them graphically, record and transmit the information have been developed separately by two French companies. The systems, Vigigraphic and Visufora, involve the linking of a master computer with various surface and downhole sensors to measure the data on a real-time (as experienced) basis and compute the information. Vigigraphic is able to produce graphic displays grouped on four screens - drilling, tripping, geological and mud data. It computes at least 200 variables from the sensor readings, and it can store over 100 variables. Visufora allows the operator to group the drilling variables as desired. It can monitor and analyze surface and downhole parameters. The system can be linked with MWD tools. Twenty channels of input are assigned to surface values and the remaining 20 channels can be used to monitor downhole instrumentation.

  17. The Oman Drilling Project

    Matter, J.; Kelemen, P. B.; Teagle, D. A. H.


    With seed funds from the Sloan Foundation, the International Continental Drilling Program (ICDP) approved a proposal by 39 international proponents for scientific drilling in the Oman ophiolite. Via observations on core, geophysical logging, fluid sampling, hydrological measurements, and microbiological sampling in a series of boreholes, we will address long-standing, unresolved questions regarding melt and solid transport in the mantle beneath oceanic spreading ridges, igneous accretion of oceanic crust, mass transfer between the oceans and the crust via hydrothermal alteration, and recycling of volatile components in subduction zones. We will undertake frontier exploration of subsurface weathering processes in mantle peridotite, including natural mechanisms of carbon dioxide uptake from surface waters and the atmosphere, and the nature of the subsurface biosphere. Societally relevant aspects include involvement and training of university students, including numerous students from Sultan Qaboos University in Oman. Studies of natural mineral carbonation will contribute to design of engineered systems for geological carbon dioxide capture and storage. Studies of alteration will contribute to fundamental understanding of the mechanisms of reaction-driven cracking, which could enhance geothermal power generation and extraction of unconventional hydrocarbon resources. We hope to begin drilling in late 2015. Meanwhile, we are seeking an additional $2M to match the combined Sloan and ICDP funding from national and international funding agencies. Matching funds are needed for operational costs of drilling, geophysical logging, downhole fluid sampling, and core description. Information on becoming part of the named investigator pool is in Appendix 14 (page 70) of the ICDP proposal, available at This formal process should begin at about the time of the 2014 Fall AGU Meeting. Meanwhile, potential

  18. Drilling comparison in "warm ice" and drill design comparison

    Augustin, L.; Motoyama, H.; Wilhelms, F.


    at each site, the drilling rate dropped and the drilling teams had to deal with refrozen ice on cutters and drill heads. Drills have different limits and perform differently. In this comparative study, we examine depth, pressure, temperature, pump flow and cutting speed. Finally, we compare a few......For the deep ice-core drilling community, the 2005/06 Antarctic season was an exciting and fruitful one. In three different Antarctic locations, Dome Fuji, EPICA DML and Vostok, deep drillings approached bedrock (the ice-water interface in the case of Vostok), emulating what had previously been...... achieved at NorthGRIP, Greenland, (summer 2003 and 2004) and at EPICA Dome C2, Antarctica (season 2004/05). For the first time in ice-core drilling history, three different types of drill (KEMS, JARE and EPICA) simultaneously reached the depth of 'warm ice' under high pressure. After excellent progress...

  19. Research of PDC Bit Compact Die With FEM and Optimum Method

    ZhouSizhu; LiChenggang; CaoJiguang; HuaJian


    In mould design, it is necessary for a designer to ensure that the cylinder has enough intensity in both the prestressed and synthesis states. An individual layer cylindrical mould cannot withstand a very high pressure needed in polycrystalline diamond composite (PDC) production. So, multi-layer prepressure combination assemble moulds are often used. The analysis conducted here is to study the interaction of cylindrical layers and to explain how to obtain enough load capability with the lowest requirement of material performance. The ratio of the pressure cylinder radius of synthetic diamond is 3.27, which is close to the optimal value and can be used as structure size in a design for PDC bit compact die. There is a linear relationship between the internal and external pressures under a special tangent stress on the inner wall of the pressure cylinder. So, when two of the three parameters (the internal pressure, external pressure, and the requirement value of the tangent stress on the inner wall of the pressure cylinder) are given, the third can be obtained. The sleeve acts as a "bridge" between the pressure cylinder and the steel belts. The optimum model developed in this paper can be used in PDC bit compact die design and other similar prestressed cold extrusion die design.

  20. New design of a compact aero-robotic drilling end effector: An experimental analysis

    Shi Zhenyun


    Full Text Available This paper presents the development of a normal adjustment cell (NAC in aero-robotic drilling to improve the quality of vertical drilling, by using an intelligent double-eccentric disk normal adjustment mechanism (2-EDNA, a spherical plain bearing and a floating compress module with sensors. After the surface normal vector is calculated based on the laser sensors’ feedback, the 2-EDNA concept is conceived specifically to address the deviation of the spindle from the surface normal at the drilling point. Following the angle calculation, depending on the actual initial position, two precise eccentric disks (PEDs with an identical eccentric radius are used to rotate with the appropriate angles using two high-resolution DC servomotors. The two PEDs will carry the spindle to coincide with the surface normal, keeping the vertex of the drill bit still to avoid repeated adjustment and position compensation. A series of experiments was conducted on an aeronautical drilling robot platform with a precise NAC. The effect of normal adjustment on bore diameter, drilling force, burr size, drilling heat, and tool wear was analyzed. The results validate that using the NAC in robotic drilling results in greatly improved vertical drilling quality and is attainable in terms of intelligence and accuracy.

  1. New design of a compact aero-robotic drilling end effector:An experimental analysis

    Shi Zhenyun; Yuan Peijiang; Wang Qishen; Chen Dongdong; Wang Tianmiao


    This paper presents the development of a normal adjustment cell (NAC) in aero-robotic drilling to improve the quality of vertical drilling, by using an intelligent double-eccentric disk nor-mal adjustment mechanism (2-EDNA), a spherical plain bearing and a floating compress module with sensors. After the surface normal vector is calculated based on the laser sensors’ feedback, the 2-EDNA concept is conceived specifically to address the deviation of the spindle from the sur-face normal at the drilling point. Following the angle calculation, depending on the actual initial position, two precise eccentric disks (PEDs) with an identical eccentric radius are used to rotate with the appropriate angles using two high-resolution DC servomotors. The two PEDs will carry the spindle to coincide with the surface normal, keeping the vertex of the drill bit still to avoid repeated adjustment and position compensation. A series of experiments was conducted on an aeronautical drilling robot platform with a precise NAC. The effect of normal adjustment on bore diameter, dril-ling force, burr size, drilling heat, and tool wear was analyzed. The results validate that using the NAC in robotic drilling results in greatly improved vertical drilling quality and is attainable in terms of intelligence and accuracy.

  2. Algebra task & drill sheets

    Reed, Nat


    For grades 6-8, our State Standards-based combined resource meets the algebraic concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills. Included are opportunities for problem-solving, patterning, algebraic graphing, equations and determining averages. The combined task & drill sheets

  3. Algebra task & drill sheets

    Reed, Nat


    For grades 3-5, our State Standards-based combined resource meets the algebraic concepts addressed by the NCTM standards and encourages the students to review the concepts in unique ways. The task sheets introduce the mathematical concepts to the students around a central problem taken from real-life experiences, while the drill sheets provide warm-up and timed practice questions for the students to strengthen their procedural proficiency skills. Included are opportunities for problem-solving, patterning, algebraic graphing, equations and determining averages. The combined task & drill sheets

  4. Drill on Android


    HES-SO DRILLER est une application de drill disponible sur Cyberlearn qui permet aux utilisateurs d’effectuer des quizz relatifs à la programmation. Le principe étant que les professeurs créent leurs quizz et les étudiants puissent y jouer. Les scores obtenus sont comptabilisés et comparés sur Facebook. Ce projet a pour but d’analyser cette application et de l’adapter afin de l’utiliser sur un client mobile Android sous le nom de Drill on Android.

  5. Diamond Pixel Detectors and 3D Diamond Devices

    Venturi, N.


    Results from detectors of poly-crystalline chemical vapour deposited (pCVD) diamond are presented. These include the first analysis of data of the ATLAS Diamond Beam Monitor (DBM). The DBM module consists of pCVD diamond sensors instrumented with pixellated FE-I4 front-end electronics. Six diamond telescopes, each with three modules, are placed symmetrically around the ATLAS interaction point. The DBM tracking capabilities allow it to discriminate between particles coming from the interaction point and background particles passing through the ATLAS detector. Also, analysis of test beam data of pCVD DBM modules are presented. A new low threshold tuning algorithm based on noise occupancy was developed which increases the DBM module signal to noise ratio significantly. Finally first results from prototypes of a novel detector using pCVD diamond and resistive electrodes in the bulk, forming a 3D diamond device, are discussed. 3D devices based on pCVD diamond were successfully tested with test beams at CERN. The measured charge is compared to that of a strip detector mounted on the same pCVD diamond showing that the 3D device collects significantly more charge than the planar device.

  6. Deep Drilling Technology of China

    Ni Rongfu


    @@ Since the drilling of well Songji-6 by the drilling crew No. 32139 in Daqing in 1963,there havebeen some 1600 over 4 000 m deep wells completed till 1993, among which two are above 7 000 m in depth.

  7. Intelligent Detection of Drill Wear

    Liu, T. I.; Chen, W. Y.; Anatharaman, K. S.


    Backpropagation neural networks (BPNs) were used for on-line detection of drill wear. The neural network consisted of three layers: input, hidden, and output. The input vector comprised drill size, feed rate, spindle speed, and eight features obtained by processing the thrust and torque signals. The output was the drill wear state which either usable or failure. Drilling experiments with various drill sizes, feed rates and spindle speeds were carried out. The learning process was performed effectively by utilising backpropagation with smoothing and an activation function slope. The on-line detection of drill wear states using BPNs achieved 100% reliability even when the drill size, feed rate and spindle speed were changed. In other words, the developed on-line drill wear detection systems have very high robustness and hence can be used in very complex production environments, such as flexible manufacturing systems.

  8. Steerable shaft drilling

    Pigott, C.P. (Pigott Shaft Drilling Ltd., Preston (UK))


    The paper outlines the techniques of steerable shaft drilling and gives brief details of the various machines currently available to carry out this task. It summarizes the many potential benefits of using this method, which could lead to more mines having multiple shafts, each serving a specific purpose. 8 figs.

  9. 45130-Drilling Crew First Enter into the International Drilling Market

    Song Zhixian; Drilling


    @@ 45130-Drilling Crew subordinate to the Fourth Drilling Company of Zhongyuan Petroleum Exploration Bureau, won the two bids of risk exploration drilling projects, respectively for China Ltd. Co. of New Zealand Petroleum Exploration Company worked in the Dongtinghu Basin in 1992 and Amoco Orient Oil Co.worked in the Fuyang area, Anhui Province in November of 1993.According to the two contracts that have been signed, the two drilling wells were successfully completed,all drilling parameters are in accordance with the requirements of both contracts.

  10. Drilling, Coring and Sampling Using Piezoelectric Actuated Mechanisms: From the USDC to a Piezo-Rotary-Hammer Drill

    Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Bao, Xiaoqi


    NASA exploration missions are increasingly including sampling tasks but with the growth in engineering experience (particularly, Phoenix Scout and MSL) it is now very much recognized that planetary drilling poses many challenges. The difficulties grow significantly with the hardness of sampled material, the depth of drilling and the harshness of the environmental conditions. To address the requirements for samplers that could be operated at the conditions of the various bodies in the solar system, a number of piezoelectric actuated drills and corers were developed by the Advanced Technologies Group of JPL. The basic configuration that was conceived in 1998 is known as the Ultrasonic/Sonic Driller/Corer (USDC), and it operates as a percussive mechanism. This drill requires as low preload as 10N (important for operation at low gravity) allowing to operate with as low-mass device as 400g, use an average power as low as 2- 3W and drill rocks as hard as basalt. A key feature of this drilling mechanism is the use of a free-mass to convert the ultrasonic vibrations generated by piezoelectric stack to sonic impacts on the bit. Using the versatile capabilities f the USDC led to the development of many configurations and device sizes. Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to remove cuttings. To reach meters deep in ice a wireline drill was developed called the Ultrasonic/Sonic Gopher and it was demonstrated in 2005 to penetrate about 2-m deep at Antarctica. Jointly with Honeybee Robotics, this mechanism is currently being modified to incorporate rotation and inchworm operation forming Auto-Gopher to reach meters deep in rocks. To take advantage of the ability of piezoelectric actuators to operate over a wide temperatures range, piezoelectric actuated drills were developed and demonstrated to operate at as cold as -200oC and as hot as 500oC. In this paper, the developed mechanisms

  11. Low complexity bit loading algorithm for OFDM system

    Yang Yu; Sha Xuejun; Zhang Zhonghua


    A new approach to loading for orthogonal frequency division multiplexing (OFDM) system is proposed, this bit-loading algorithm assigns bits to different subchannels in order to minimize the transmit energy. In the algorithm,first most bit are allocated to each subchannels according to channel condition, Shannon formula and QoS require of the user, then the residual bit are allocated to the subchannels bit by bit. In this way the algorithm is efficient while calculation is less complex. This is the first time to load bits with the scale following Shannon formula and the algorithm is of O (4N) complexity.

  12. Modeling and Adhesive Tool Wear in Dry Drilling of Aluminum Alloys

    Girot, F.; Gutiérrez-Orrantia, M. E.; Calamaz, M.; Coupard, D.


    One of the challenges in aeronautic drilling operations is the elimination of cutting fluids while maintaining the quality of drilled parts. This paper therefore aims to increase the tool life and process quality by working on relationships existing between drilling parameters (cutting speed and feed rate), coatings and tool geometry. In dry drilling, the phenomenon of Built-Up Layer is the predominant damage mechanism. A model fitting the axial force with the cutting parameters and the damage has been developed. The burr thickness and its dispersion decrease with the feed rate. The current diamond coatings which exhibit a strong adhesion to the carbide substrate can limit this adhesive layer phenomenon. A relatively smooth nano-structured coating strongly limits the development of this layer.

  13. High efficiency diamond solar cells

    Gruen, Dieter M.


    A photovoltaic device and method of making same. A layer of p-doped microcrystalline diamond is deposited on a layer of n-doped ultrananocrystalline diamond such as by providing a substrate in a chamber, providing a first atmosphere containing about 1% by volume CH.sub.4 and about 99% by volume H.sub.2 with dopant quantities of a boron compound, subjecting the atmosphere to microwave energy to deposit a p-doped microcrystalline diamond layer on the substrate, providing a second atmosphere of about 1% by volume CH.sub.4 and about 89% by volume Ar and about 10% by volume N.sub.2, subjecting the second atmosphere to microwave energy to deposit a n-doped ultrananocrystalline diamond layer on the p-doped microcrystalline diamond layer. Electrodes and leads are added to conduct electrical energy when the layers are irradiated.

  14. Designing of concrete diamond sawblade

    ZHANG Shao-he; DING Xin-yu; ZHOU Jia-xiang


    By analyzing the abrasive theory of concrete diamond sawblade, the proposal that the diamond should be selected by its function in cutting concrete is presented. The part of the big grit diamonds cut rock, and the part of the small grit diamonds improve the wearability of the matrix. The contrast tests are done with different shapes of sawbaldes in split segment, slant "U" slot segment, sandwich segment, turbo segment and three-slot segment. The special shapes of sawblades can improve the effect of cooling and the removing ability of the rock powder. The data of tests show that the efficiency of cutting and the life of sawblades are improved by designing the diamond prescription and using the especial geometry of segment.

  15. Single ion impact detection and scanning probe aligned ion implantation for quantum bit formation

    Weis, Christoph D.


    Quantum computing and quantum information processing is a promising path to replace classical information processing via conventional computers which are approaching fundamental physical limits. Instead of classical bits, quantum bits (qubits) are utilized for computing operations. Due to quantum mechanical phenomena such as superposition and entanglement, a completely different way of information processing is achieved, enabling enhanced performance for certain problem sets. Various proposals exist on how to realize a quantum bit. Among them are electron or nuclear spins of defect centers in solid state systems. Two such candidates with spin degree of freedom are single donor atoms in silicon and nitrogen vacancy (NV) defect centers in diamond. Both qubit candidates possess extraordinary qualities which makes them promising building blocks. Besides certain advantages, the qubits share the necessity to be placed precisely in their host materials and device structures. A commonly used method is to introduce the donor atoms into the substrate materials via ion implantation. For this, focused ion beam systems can be used, or collimation techniques as in this work. A broad ion beam hits the back of a scanning probe microscope (SPM) cantilever with incorporated apertures. The high resolution imaging capabilities of the SPM allows the non destructive location of device areas and the alignment of the cantilever and thus collimated ion beam spot to the desired implant locations. In this work, this technique is explored, applied and pushed forward to meet necessary precision requirements. The alignment of the ion beam to surface features, which are sensitive to ion impacts and thus act as detectors, is demonstrated. The technique is also used to create NV center arrays in diamond substrates. Further, single ion impacts into silicon device structures are detected which enables deliberate single ion doping.

  16. Reservoir pressure evolution model during exploration drilling

    Korotaev B. A.


    Full Text Available Based on the analysis of laboratory studies and literature data the method for estimating reservoir pressure in exploratory drilling has been proposed, it allows identify zones of abnormal reservoir pressure in the presence of seismic data on reservoir location depths. This method of assessment is based on developed at the end of the XX century methods using d- and σ-exponentials taking into account the mechanical drilling speed, rotor speed, bit load and its diameter, lithological constant and degree of rocks' compaction, mud density and "regional density". It is known that in exploratory drilling pulsation of pressure at the wellhead is observed. Such pulsation is a consequence of transferring reservoir pressure through clay. In the paper the mechanism for transferring pressure to the bottomhole as well as the behaviour of the clay layer during transmission of excess pressure has been described. A laboratory installation has been built, it has been used for modelling pressure propagation to the bottomhole of the well through a layer of clay. The bulge of the clay layer is established for 215.9 mm bottomhole diameter. Functional correlation of pressure propagation through the layer of clay has been determined and a reaction of the top clay layer has been shown to have bulge with a height of 25 mm. A pressure distribution scheme (balance has been developed, which takes into account the distance from layers with abnormal pressure to the bottomhole. A balance equation for reservoir pressure evaluation has been derived including well depth, distance from bottomhole to the top of the formation with abnormal pressure and density of clay.

  17. Diamond Anvil Cell Techniques

    Piermarini, Gasper J.

    It has often been said that scientific advances are made either in a dramatic and revolutionary way, or, as in the case of the diamond anvil cell (DAC), in a slow and evolutionary manner over a period of several years. For more than 2 decades, commencing in 1958, the DAC developed stepwise from a rather crude qualitative instrument to the sophisticated quantitative research tool it is today, capable of routinely producing sustained static pressures in the multi-megabar range and readily adaptable to numerous scientific measurement techniques because of its optical accessibility, miniature size, and portability.

  18. Primitive helium in diamonds

    Ozima, M.; Zashu, S.


    He-3/He-4 isotopic ratio analyses of 13 diamond stones from unspecified mines in South Africa yield values ranging from less than 10 to the -7th to 0.00032 + or - 0.000025. The latter value is higher than the primordial He-3/He-4 ratio in meteorites, and close to the ratio for solar type He. It is suggested that these elevated values may represent primitive He which has evolved little, in view of its minute increase in radiogenic He-4, since the earth's formation.

  19. Heteroepitaxial Diamond Growth


    interstitials, respectively. The energies required for the planar to puckered distortion are 4.3 eV on Ni(l 11), 3.0 eV with the Na interstitial, 3.6 eV with H...give consideration to the crystallographic I alignment between diamond tiles to minimize dislocation densities at the " seams ". 3 Methods of checking the...crystallographic alignment (non-destructively) and assessing the dislocation densities at seams must be used to establish the viability of 3 any

  20. Ultra low bit-rate speech coding

    Ramasubramanian, V


    "Ultra Low Bit-Rate Speech Coding" focuses on the specialized topic of speech coding at very low bit-rates of 1 Kbits/sec and less, particularly at the lower ends of this range, down to 100 bps. The authors set forth the fundamental results and trends that form the basis for such ultra low bit-rates to be viable and provide a comprehensive overview of various techniques and systems in literature to date, with particular attention to their work in the paradigm of unit-selection based segment quantization. The book is for research students, academic faculty and researchers, and industry practitioners in the areas of speech processing and speech coding.

  1. Bit-padding information guided channel hopping

    Yang, Yuli


    In the context of multiple-input multiple-output (MIMO) communications, we propose a bit-padding information guided channel hopping (BP-IGCH) scheme which breaks the limitation that the number of transmit antennas has to be a power of two based on the IGCH concept. The proposed scheme prescribes different bit-lengths to be mapped onto the indices of the transmit antennas and then uses padding technique to avoid error propagation. Numerical results and comparisons, on both the capacity and the bit error rate performances, are provided and show the advantage of the proposed scheme. The BP-IGCH scheme not only offers lower complexity to realize the design flexibility, but also achieves better performance. © 2011 IEEE.

  2. Development and testing of a high-pressure downhole pump for jet-assist drilling. Topical report, Phase II



    The goal of jet-assisted drilling is to increase the rate of penetration (ROP) in deeper gas and oil wells, where the rocks become harder and more difficult to drill. Increasing the ROP can result in fewer drilling days, and therefore, lower drilling cost. In late 1993, FlowDril and the Gas Research Institute (GRI) began a three-year development of a down hole pump (DHP{reg_sign}) capable of producing 30,000 psi out pressure to provide the high-pressure flow for high-pressure jet-assist of the drill bit. The U.S. Department of Energy (DOE) through its Morgantown, WV (DOE-Morgantown) field office, joined with GRI and FlowDril to develop and test a second prototype designed for drilling in 7-7/8 inch holes. This project, {open_quotes}Development and Testing of a High-Pressure Down Hole Pump for Jet-Assist Drilling,{close_quotes} is for the development and testing of the second prototype. It was planned in two phases. Phase I included an update of a market analysis, a design, fabrication, and an initial laboratory test of the second prototype. Phase II is continued iterative laboratory and field developmental testing. This report summarizes the results of Phase II. In the downhole pump approach shown in the following figure, conventional drill pipe and drill collars are used, with the DHP as the last component of the bottom hole assembly next to the bit. The DHP is a reciprocating double ended, intensifier style positive displacement, high-pressure pump. The drive fluid and the high-pressure output fluid are both derived from the same source, the abrasive drilling mud pumped downhole through the drill string. Approximately seven percent of the stream is pressurized to 30,000 psi and directed through a high-pressure nozzle on the drill bit to produce the high speed jet and assist the mechanical action of the bit to make it drill faster.

  3. Method of drilling with magnetorheological fluid

    Zitha, P.L.J.


    A method of drilling a bore hole into a stratum, wherein via the drill hole drilling fluid is introduced and fed to the drill head. In order to avoid dilution or leak-off of the drilling fluid the same is in accordance with the invention a magnetorheological drilling fluid, and when an undesirable p

  4. Parameter definition using vibration prediction software leads to significant drilling performance improvements

    Amorim, Dalmo; Hanley, Chris Hanley; Fonseca, Isaac; Santos, Juliana [National Oilwell Varco, Houston TX (United States); Leite, Daltro J.; Borella, Augusto; Gozzi, Danilo [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)


    The understanding and mitigation of downhole vibration has been a heavily researched subject in the oil industry as it results in more expensive drilling operations, as vibrations significantly diminish the amount of effective drilling energy available to the bit and generate forces that can push the bit or the Bottom Hole Assembly (BHA) off its concentric axis of rotation, producing high magnitude impacts with the borehole wall. In order to drill ahead, a sufficient amount of energy must be supplied by the rig to overcome the resistance of the drilling system, including the reactive torque of the system, drag forces, fluid pressure losses and energy dissipated by downhole vibrations, then providing the bit with the energy required to fail the rock. If the drill string enters resonant modes of vibration, not only does it decreases the amount of available energy to drill, but increases the potential for catastrophic downhole equipment and drilling bit failures. In this sense, the mitigation of downhole vibrations will result in faster, smoother, and cheaper drilling operations. A software tool using Finite Element Analysis (FEA) has been developed to provide better understanding of downhole vibration phenomena in drilling environments. The software tool calculates the response of the drilling system at various input conditions, based on the design of the wellbore along with the geometry of the Bottom Hole Assembly (BHA) and the drill string. It identifies where undesired levels of resonant vibration will be driven by certain combinations of specific drilling parameters, and also which combinations of drilling parameters will result in lower levels of vibration, so the least shocks, the highest penetration rate and the lowest cost per foot can be achieved. With the growing performance of personal computers, complex software systems modeling the drilling vibrations using FEA has been accessible to a wider audience of field users, further complimenting with real time

  5. Data network, collection, and analysis in the Diamond Valley flow system, central Nevada

    Knochenmus, Lari A.; Berger, David L.; Moreo, Michael T.; Smith, J. LaRue


    Future groundwater development and its effect on future municipal, irrigation, and alternative energy uses in the Diamond Valley flow system are of concern for officials in Eureka County, Nevada. To provide a better understanding of the groundwater resources, the U.S. Geological Survey, in cooperation with Eureka County, commenced a multi-phase study of the Diamond Valley flow system in 2005. Groundwater development primarily in southern Diamond Valley has resulted in water-level declines since the 1960s ranging from less than 5 to 100 feet. Groundwater resources in the Diamond Valley flow system outside of southern Diamond Valley have been relatively undeveloped. Data collected during phase 2 of the study (2006-09) included micrometeorological data at 4 evapotranspiration stations, 3 located in natural vegetation and 1 located in an agricultural field; groundwater levels in 95 wells; water-quality constituents in aquifers and springs at 21 locations; lithologic information from 7 recently drilled wells; and geophysical logs from 3 well sites. This report describes what was accomplished during phase 2 of the study, provides the data collected, and presents the approaches to strengthen relations between evapotranspiration rates measured at micrometeorological stations and spatially distributed groundwater discharge. This report also presents the approach to improve delineation of areas of groundwater discharge and describes the current methodology used to improve the accuracy of spatially distributed groundwater discharge rates in the Diamond Valley flow system.

  6. Drilling techniques for osteochondritis dissecans.

    Heyworth, Benton E; Edmonds, Eric W; Murnaghan, M Lucas; Kocher, Mininder S


    Although the advanced stages of osteochondritis dissecans remain challenging to treat, most early-stage lesions in skeletally immature patients, if managed appropriately, can be stimulated to heal. For stable lesions that do not demonstrate adequate healing with nonoperative measures, such as activity modification, weight-bearing protection, or bracing, drilling of the subchondral bone has emerged as the gold standard of management. Several techniques of drilling exist, including transarticular drilling, retroarticular drilling, and notch drilling. Although each technique has been shown to be effective in small retrospective studies, higher-powered prospective comparative studies are needed to better elucidate their relative advantages and disadvantages.

  7. Synthesis of Diamond Films with Pulsed Plasma


    Diamond and Diamond-Like Films, The Electrochemical Society , Los Angeles, California, Volume 89-12, 114, May 1989. M. Aklufi and D. Brock, "Synthesis Of...Diamond Films By Microwave Generated Pulsed Plasmas," Proceedings of The Second International Symposium On Diamond Materials, The Electrochemical Society , Washington, DC, Volume 91-8, ’ 39, May 1991.

  8. Optical cryocooling of diamond

    Kern, M.; Jeske, J.; Lau, D. W. M.; Greentree, A. D.; Jelezko, F.; Twamley, J.


    The cooling of solids by optical means only using anti-Stokes emission has a long history of research and achievements. Such cooling methods have many advantages ranging from no moving parts or fluids through to operation in vacuum and may have applications to cryosurgery. However, achieving large optical cryocooling powers has been difficult to manage except in certain rare-earth crystals but these are mostly toxic and not biocompatible. Through study of the emission and absorption cross sections we find that diamond, containing either nitrogen vacancy (NV) or silicon vacancy defects, shows potential for optical cryocooling and, in particular, NV doping shows promise for optical refrigeration. We study the optical cooling of doped diamond microcrystals ranging 10-250 μ m in diameter trapped either in vacuum or in water. For the vacuum case we find NV-doped microdiamond optical cooling below room temperature could exceed |Δ T |>10 K for irradiation powers of Pin<100 mW. We predict that such temperature changes should be easily observed via large alterations in the diffusion constant for optically cryocooled microdiamonds trapped in water in an optical tweezer or via spectroscopic signatures such as the zero-phonon line width or Raman line.

  9. Transmission diamond imaging detector

    Smedley, John, E-mail:; Pinelli, Don; Gaoweia, Mengjia [Brookhaven National Laboratory, Upton, NY (United States); Muller, Erik; Ding, Wenxiang; Zhou, Tianyi [Stony Brook University, Stony Brook, NY (United States); Bohon, Jen [Case Center for Synchrotron Biosciences, Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH (United States)


    Many modern synchrotron techniques are trending toward use of high flux beams and/or beams which require enhanced stability and precise understanding of beam position and intensity from the front end of the beamline all the way to the sample. For high flux beams, major challenges include heat load management in optics (including the vacuum windows) and a mechanism of real-time volumetric measurement of beam properties such as flux, position, and morphology. For beam stability in these environments, feedback from such measurements directly to control systems for optical elements or to sample positioning stages would be invaluable. To address these challenges, we are developing diamond-based instrumented vacuum windows with integrated volumetric x-ray intensity, beam profile and beam-position monitoring capabilities. A 50 µm thick single crystal diamond has been lithographically patterned to produce 60 µm pixels, creating a >1kilopixel free-standing transmission imaging detector. This device, coupled with a custom, FPGA-based readout, has been used to image both white and monochromatic x-ray beams and capture the last x-ray photons at the National Synchrotron Light Source (NSLS). This technology will form the basis for the instrumented end-station window of the x-ray footprinting beamline (XFP) at NSLS-II.

  10. Presolar Diamond in Meteorites

    Amari, Sachiko


    Presolar diamond, the carrier of the isotopically anomalous Xe component Xe-HL, was the first mineral type of presolar dust that was isolated from meteorites. The excesses in the light, p-process only isotopes 124Xe and 126Xe, and in the heavy, r-process only isotopes 134Xe and 136Xe relative to the solar ratios indicate that Xe-HL was produced in supernovae: they are the only stellar source where these two processes are believed to take place. Although these processes occur in supernovae, their physical conditions and timeframes are completely different. Yet the excesses are always correlated in diamond separates from meteorites. Furthermore, the p-process 124Xe/126Xe inferred from Xe-L and the r-process 134Xe/136Xe from Xe-H do not agree with the p-process and r-process ratios derived from the solar system abundance, and the inferred p-process ratio does not agree with those predicted from stellar models. The 'rapid separation scenario', where the separation of Xe and its radiogenic precursors Te and I take...

  11. Is It Possible to Ignore Problems Rising During Vertical Drilling? A Review

    Saleem Qadir Tunio


    Full Text Available The drilling process in petroleum industry is directly proportional with economics and if even a small problems encounters on any point during drilling will might results a commercial loss (i.e. economics and time factor. This study is based on the study of all those hindrances/problems often encounters during vertical drilling and ways to combat against those problems. Now, these days although the drilling have been an advanced practice but the problems are still of same nature like (bore-hole instability, loss-circulation, drill pipe sticking, gas cuts in a shallow formation, salt dome, kick and back flow. This study focuses above problems which are not natural but it is due to human error or may be the improper handling of the tool during the operation but these are critical with reference to the time factor and also budgeting is there. So, if these occur then the possible remedial actions in order to save the time factor as well as the economics are kept and handled accordingly. This may involve, the proper design of drilling components regarding given geophysical data of formation, proper usage of drilling fluid to avoid bit balling, formation sloughing, maintaining hydrostatic pressure and proper usage of blow out preventor to control abnormal pressures, so that a good drilling performance will be taken into account by setting up a benchmarking process that is termed to be as “a necessity for survival”.

  12. High Temperature Piezoelectric Drill

    Bao, Xiaoqi; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Shrout, Tom


    Venus is one of the planets in the solar systems that are considered for potential future exploration missions. It has extreme environment where the average temperature is 460 deg C and its ambient pressure is about 90 atm. Since the existing actuation technology cannot maintain functionality under the harsh conditions of Venus, it is a challenge to perform sampling and other tasks that require the use of moving parts. Specifically, the currently available electromagnetic actuators are limited in their ability to produce sufficiently high stroke, torque, or force. In contrast, advances in developing electro-mechanical materials (such as piezoelectric and electrostrictive) have enabled potential actuation capabilities that can be used to support such missions. Taking advantage of these materials, we developed a piezoelectric actuated drill that operates at the temperature range up to 500 deg C and the mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) configuration. The detailed results of our study are presented in this paper

  13. Offset drilling obligations

    Boyd, K.D.; Kalmakoff, J.J. [Kanuka Thuringer, Regina, SK (Canada)


    A review of the `offset well` clause found in freehold and Crown natural gas and petroleum leases was presented. The objective was to provide lessors and lessees with a clear understanding of the rights and obligations associated with offset wells. It was noted that offset well obligations vary according to the form of lease used, the type of offsetting well, the regulatory regime and the geophysical characteristics of the producing formation. Some suggestions were made as to how current versions of the offset well clause can be amended to overcome some of the problems encountered in applying the clause to an offset horizontal well that has been drilled on adjoining lands. Failure to resolve the new issues presented by horizontal drilling technology in terms of documentation, which records respective rights and obligations on the basis of generally accepted principles, will result in large numbers of conflicts and unnecessary litigation. 144 refs., 1 fig.

  14. Telescopic drilling rod

    Kagan, I.L.; Berezov, S.I.; Gavrilov, G.A.; Goykhman, Ya.A.; Makushkin, D.O.; Rachev, M.P.; Voynich, L.K.


    The telescopic drilling rod includes an inner section of the rod, in whose center cable has been passed and is attached a bearing assembly connecting it to the winch, outer section of rod along which there is pipeline connecting the working cavity formed by the inner section of rod and the housing, installed on the lower end of the outer section of rod, with cavity formed by framework of the guide swivel and end piece and connected to the hydraulic system of the machine by pipeline, as well as clamping elements. In order to drill wells to a depth greater than the length of the outer sectrion of the rod, the latter jointly with the inner section of rod is lowered into the extreme lower position until swivel rests on the feed mechanism. With further slipping of cable and the absence of pressure in the hydraulic system, clamping elements do not have an effect on the inner section of rod. It has the opportunity to freely move along the outer section of rod downwards to the face. When pressure is supplied on pipeline into cavity and further through pipeline into working cavity, the inner section of rod is clamped with feed of the outer section in the process of drilling, both sections move jointly. Because of the link between working cavity of sleeve installed on the lower end of the outer section of rod, and the hydraulic system of the machine through the swivel cavity, it is possible to fix the drilling rod in any mutual axial position of the section.

  15. Miniature Low-Mass Drill Actuated by Flextensional Piezo Stack

    Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph


    Recent experiments with a flextensional piezoelectric actuator have led to the development of a sampler with a bit that is designed to produce and capture a full set of sample forms including volatiles, powdered cuttings, and core fragments. The flextensional piezoelectric actuator is a part of a series of devices used to amplify the generated strain from piezoelectric actuators. Other examples include stacks, bimorphs, benders, and cantilevers. These devices combine geometric and resonance amplifications to produce large stroke at high power density. The operation of this sampler/drill was demonstrated using a 3x2x1-cm actuator weighing 12 g using power of about 10-W and a preload of about 10 N. A limestone block was drilled to a depth of about 1 cm in five minutes to produce powdered cuttings. It is generally hard to collect volatiles from random surface profiles found in rocks and sediment, powdered cuttings, and core fragments. Toward the end of collecting volatiles, the actuator and the bit are covered with bellows-shaped shrouds to prevent fines and other debris from reaching the analyzer. A tube with a miniature bellows (to provide flexibility) is connected to the bit and directs the flow of the volatiles to the analyzer. Another modality was conceived where the hose is connected to the bellows wall directly to allow the capture of volatiles generated both inside and outside the bit. A wide variety of commercial bellows used in the vacuum and microwave industries can be used to design the volatiles capture mechanism. The piezoelectric drilling mechanism can potentially be operated in a broad temperature range from about-200 to less than 450 C. The actuators used here are similar to the actuators that are currently baselined to fly as part of the inlet funnel shaking mechanism design of MSL (Mars Science Laboratory). The space qualification of these parts gives this drill a higher potential for inclusion in a future mission, especially when considering its

  16. High Temperature Piezoelectric Drill

    Bao, Xiaoqi; Scott, James; Boudreau, Kate; Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Shrout, Tom; Zhang, Shujun


    The current NASA Decadal mission planning effort has identified Venus as a significant scientific target for a surface in-situ sampling/analyzing mission. The Venus environment represents several extremes including high temperature (460 deg C), high pressure (9 MPa), and potentially corrosive (condensed sulfuric acid droplets that adhere to surfaces during entry) environments. This technology challenge requires new rock sampling tools for these extreme conditions. Piezoelectric materials can potentially operate over a wide temperature range. Single crystals, like LiNbO3, have a Curie temperature that is higher than 1000 deg C and the piezoelectric ceramics Bismuth Titanate higher than 600 deg C. A study of the feasibility of producing piezoelectric drills that can operate in the temperature range up to 500 deg C was conducted. The study includes the high temperature properties investigations of engineering materials and piezoelectric ceramics with different formulas and doping. The drilling performances of a prototype Ultrasonic/Sonic Drill/Corer (USDC) using high temperate piezoelectric ceramics and single crystal were tested at temperature up to 500 deg C. The detailed results of our study and a discussion of the future work on performance improvements are presented in this paper.

  17. Linear, Constant-rounds Bit-decomposition

    Reistad, Tord; Toft, Tomas


    When performing secure multiparty computation, tasks may often be simple or difficult depending on the representation chosen. Hence, being able to switch representation efficiently may allow more efficient protocols. We present a new protocol for bit-decomposition: converting a ring element x ∈ ℤ M...

  18. 1 /N perturbations in superstring bit models

    Thorn, Charles B.


    We develop the 1 /N expansion for stable string bit models, focusing on a model with bit creation operators carrying only transverse spinor indices a =1 ,…,s . At leading order (N =∞ ), this model produces a (discretized) light cone string with a "transverse space" of s Grassmann worldsheet fields. Higher orders in the 1 /N expansion are shown to be determined by the overlap of a single large closed chain (discretized string) with two smaller closed chains. In the models studied here, the overlap is not accompanied with operator insertions at the break/join point. Then, the requirement that the discretized overlap has a smooth continuum limit leads to the critical Grassmann "dimension" of s =24 . This "protostring," a Grassmann analog of the bosonic string, is unusual, because it has no large transverse dimensions. It is a string moving in one space dimension, and there are neither tachyons nor massless particles. The protostring, derived from our pure spinor string bit model, has 24 Grassmann dimensions, 16 of which could be bosonized to form 8 compactified bosonic dimensions, leaving 8 Grassmann dimensions—the worldsheet content of the superstring. If the transverse space of the protostring could be "decompactified," string bit models might provide an appealing and solid foundation for superstring theory.

  19. Reinforcement Learning in BitTorrent Systems

    Izhak-Ratzin, Rafit; van der Schaar, Mihaela


    Recent research efforts have shown that the popular BitTorrent protocol does not provide fair resource reciprocation and may allow free-riding. In this paper, we propose a BitTorrent-like protocol that replaces the peer selection mechanisms in the regular BitTorrent protocol with a novel reinforcement learning (RL) based mechanism. Due to the inherent opration of P2P systems, which involves repeated interactions among peers over a long period of time, the peers can efficiently identify free-riders as well as desirable collaborators by learning the behavior of their associated peers. Thus, it can help peers improve their download rates and discourage free-riding, while improving fairness in the system. We model the peers' interactions in the BitTorrent-like network as a repeated interaction game, where we explicitly consider the strategic behavior of the peers. A peer, which applies the RL-based mechanism, uses a partial history of the observations on associated peers' statistical reciprocal behaviors to deter...

  20. Hey! A Mosquito Bit Me! (For Kids)

    ... or Too Short All About Puberty Hey! A Mosquito Bit Me! KidsHealth > For Kids > Hey! A Mosquito ... español ¡Ay! ¡Me picó un mosquito! What's a Mosquito? A mosquito (say: mus-KEE-toe) is an ...

  1. Bit corruption correlation and autocorrelation in a stochastic binary nano-bit system

    Sa-nguansin, Suchittra


    The corruption process of a binary nano-bit model resulting from an interaction with N stochastically-independent Brownian agents (BAs) is studied with the help of Monte-Carlo simulations and analytic continuum theory to investigate the data corruption process through the measurement of the spatial two-point correlation and the autocorrelation of bit corruption at the origin. By taking into account a more realistic correlation between bits, this work will contribute to the understanding of the soft error or the corruption of data stored in nano-scale devices.

  2. Tailoring nanocrystalline diamond film properties

    Gruen, Dieter M.; McCauley, Thomas G.; Zhou, Dan; Krauss, Alan R.


    A method for controlling the crystallite size and growth rate of plasma-deposited diamond films. A plasma is established at a pressure in excess of about 55 Torr with controlled concentrations of hydrogen up to about 98% by volume, of unsubstituted hydrocarbons up to about 3% by volume and an inert gas of one or more of the noble gases and nitrogen up to about 98% by volume. The volume ratio of inert gas to hydrogen is preferably maintained at greater than about 4, to deposit a diamond film on a suitable substrate. The diamond film is deposited with a predetermined crystallite size and at a predetermined growth rate.

  3. The radial cutting torch device application due to drill string sticking

    Leković Branko


    Full Text Available Stuck pipe is a common problem with tremendous impact on drilling efficiency and costs in the oil industry. Generally, the stuck pipe troubles are solved after their occurrences by using some standard operational procedures such as working the drill string up or down, attempting to rotate the string and pumping mud at higher flow rates through the drill bit to aid pipe release. One may also place different fluids around the stick area and use a drilling jar. However, in cases where common solutions don't work, then the cutoff is the last resort. To have a successful cutoff operation, estimating the location of the free point and choosing the right cutting tool is of vital importance. This paper presents the Radial Cutting Torch (RCT as a innovative cutting tool and its oilfield application in stuck pipe events.

  4. Experimental Study Optimizing Hole Cleaning-Cuttings Transport in Oil Drilling Engineering

    Ibrahim A A; Musa T A


    With a clear understanding of the drilling fluid techniques and the cutting-taking mechanism, a new advanced model is set up for analyzing field data and quantitative forecast of cutting-taking mechanism. Therefore, a number of values affecting the drilling rate and the hole cleaning are studied over a wide range of parameters. Drilling data obtained under high-borehole-pressure conditions are analyzed to determine the causes of the reduction in rate of penetration (ROP) as the borehole pressure increases, which in some cases is caused by the buildup of rock debris under the bit. The theoretical achievement and testing conclusions can be very instructional for horizontal well drilling. Much higher annular velocities are required for effective hole cleaning in directional wells than in vertical wells. Highviscosity muds are observed to provide better transport than low-viscosity muds.


    Leonard Marius CIUREZU GHERGHE


    Full Text Available This paper aims to highlight the influence of cutting regime on the wear drills at steel processing , in particular the processing of stainless steel X17CrNi16-2 SR EN 10088-4 DIN 17440. We are interested in wear of the drill at processing of this type of stainless steel , which has applicability in energy industry given the special characteristics of its. We want a maximum value of 0.2 mm for the wear of the drill, measurement and taking pictures are made using a microscope DigiMicro 2.0 and the software used is MicroCapture. Processing was done on machining center YMC YOUNG TECH 1050, and the tool used was 8 mm drill bit high speed steel.

  6. Study on electroplating technology of diamond tools for machining hard and brittle materials

    Cui, Ying; Chen, Jian Hua; Sun, Li Peng; Wang, Yue


    With the development of the high speed cutting, the ultra-precision machining and ultrasonic vibration technique in processing hard and brittle material , the requirement of cutting tools is becoming higher and higher. As electroplated diamond tools have distinct advantages, such as high adaptability, high durability, long service life and good dimensional stability, the cutting tools are effective and extensive used in grinding hard and brittle materials. In this paper, the coating structure of electroplating diamond tool is described. The electroplating process flow is presented, and the influence of pretreatment on the machining quality is analyzed. Through the experimental research and summary, the reasonable formula of the electrolyte, the electroplating technologic parameters and the suitable sanding method were determined. Meanwhile, the drilling experiment on glass-ceramic shows that the electroplating process can effectively improve the cutting performance of diamond tools. It has laid a good foundation for further improving the quality and efficiency of the machining of hard and brittle materials.

  7. Analysis of Surface Integrity in Drilling Metal Matrix and Hybrid Metal Matrix Composites

    T. Rajmohan; K. Palanikumar; J. Paulo Davim


    Hybrid metal matrix composites consist of at least three constituents-a metal or an alloy matrix and two reinforcements in various forms, bonded together at the atomic level in the composite. Despite their higher specific properties of strength and stiffness, the non homogeneous and anisotropic nature combined with the abrasive reinforcements render their machining difficult. In this paper, the surface integrity of machining in drilling hybrid composites has been discussed. Drilling tests are carried out at different spindle speed, feed rates, and different drill tool materials to investigate the effect of the various cutting parameters on the surface quality and the extent of the deformation of drilled surface due to drilling. Materials used for the present investigation are A1356/IOSIC (wt%) metal matrix and A1356/10SiC-3mica (wt%) hybrid composites. The composites are fabricated using stir casting route. The drilling tests are conducted on vertical computer numeric control (CNC) machining center using carbide, coated carbide and polycrystalline diamond (PCD) drills. The surface roughness decreases with increasing spindle speed and increases with increasing feed rate. The machined surface is analyzed by scanning electron microscopy (SEM). SEM images of the machined surfaces indicate the presence of grooves and pits. Microhardness depth profiles indicate that the subsurface damage is limited to the top of 100-250 μm.

  8. The Diamond Standard Vodka酒


    对于酒的品味不仅仅在酒本身所散发出的醉人魅力,自古以来,拥有艺术品般精湛做工、华美造犁的盛酒器皿也和酒一样流传千古。The Diamond Standard Vodka以“奢侈”、“豪华”作为卖点,除了散发着北欧风格的高贵气质外,由原产自奥地利的施华洛廿奇水晶制成25mm的瓶身更让它身价倍增。以钻石命名的它使用了钻石过滤专利系统,

  9. Importance of drill string assembly swivel in horizontal drilling

    Edmund Tasak


    Full Text Available A part of the drill string – the swivel (rotational connector – accomplishes an important task in the horizontal drilling. Its malfunctioning makes it impossible to draw in ( install large diameter and length pipelines. The causes of the connector break-down during the horizontal drilling are investigated in the paper. The drilling has been made for twenty inches gas pipeline installation during reaming operations. A trouble was encountered making good work conditions of a system consisting of the drilling machine drill string reamer swivel tube shield of Cardan joint and the gas pipeline 500 m long. In this case, the swivel brokes down and the planned operation was not finished. The assessment of improper drilling conditions, selection of operation system components, and drilling parameters and the insufficient technological supervising have created an excessive risk of failure. A proper application of technical analysis would considerably decrease the hazard of failure which cause large costs, delays and decrease of confidence to the drilling contractor and pipeline installation.

  10. Perbandingan Kecepatan Pencacahan Antara Timer 0 (8 Bit Dengan Timer 1 (16 Bit Pada Sistem Mikrokontroler

    Arief Hendra Saptadi


    Full Text Available The application of timer/counter in microcontroller system had provided advantages in a way that it didn’t put the burden on CPU resources and enabled CPU to perform other tasks. With the availability of 8-bit and 16-bit timer/counter, the problem laid on the selection of the type of timer/counter being used. From the experiments performed, the minimum system of AVR ATmega8535 microcontroller had precisely counted a number using two different timers/counters, namely, Timer/Counter 0 (8 bit and Timer/Counter 1 (16 bit. The overflow condition achieved on 8-bit and 16-bit counting cycle activated OCR0 and OCR1AL registers, respectively. Output signals from port B.3 (OC0 and port D.5 (OC1A  are then fed to oscilloscope and put into comparison. From the observation of output signals, it could be proven that the two different timers/counters had equal counting speed. Hence, it can be concluded that the selection of timers/counters is more likely based on the flexibility of count range, program size and execution time

  11. Helium and carbon isotopes in Indian diamonds

    Wiens, R.; Lal, D.; Craig, H.


    Helium and carbon isotope measurements in Indian diamonds (from Andhra Pradesh) were carried out using samples that included mined diamonds from primary kimberlite source rocks and alluvial diamonds from river gravel. The He and C isotope concentrations in diamonds from these two sources were compared, and the Indian diamonds were compared to those from other regions. Results indicate that most of the He-3 in the alluvial diamonds is of cosmogenic origin and that the alluvial diamonds may also have a significant He-4 component due to alpha particles implanted during storage in a secondary matrix. One diamond, a mined kimberlite specimen, was found to have the lowest He-4 content (0.018 microcc/g) so far recorded in diamonds.

  12. Computer Series, 99: Bits and Pieces, 39.

    Moore, John W., Ed.


    Presents five computer programs: (1) Accurate Numerical Solutions of the One-Dimensional Schrodinger Equation; (2) NMR Simulation and Interactive Drill/Interpretation; (3) A Simple Computer Program for the Calculation of 13C-NMR Chemical Shifts; (4) Constants of 1:1 Complexes from NMR or Spectrophotometric Measurements; and (5) Saturation…

  13. Computer Series, 13: Bits and Pieces, 11.

    Moore, John W., Ed.


    Describes computer programs (with ordering information) on various topics including, among others, modeling of thermodynamics and economics of solar energy, radioactive decay simulation, stoichiometry drill/tutorial (in Spanish), computer-generated safety quiz, medical chemistry computer game, medical biochemistry question bank, generation of…

  14. Quantum photonic networks in diamond

    Lončar, Marko


    Advances in nanotechnology have enabled the opportunity to fabricate nanoscale optical devices and chip-scale systems in diamond that can generate, manipulate, and store optical signals at the single-photon level. In particular, nanophotonics has emerged as a powerful interface between optical elements such as optical fibers and lenses, and solid-state quantum objects such as luminescent color centers in diamond that can be used effectively to manipulate quantum information. While quantum science and technology has been the main driving force behind recent interest in diamond nanophotonics, such a platform would have many applications that go well beyond the quantum realm. For example, diamond\\'s transparency over a wide wavelength range, large third-order nonlinearity, and excellent thermal properties are of great interest for the implementation of frequency combs and integrated Raman lasers. Diamond is also an inert material that makes it well suited for biological applications and for devices that must operate in harsh environments. Copyright © Materials Research Society 2013.

  15. Sample application to test site No. 1, Kenedy Co. [Offset well information, drilling fluids program, cost estimates, and data acquisition

    Podio, A.L.; Gray, K.E.; Isokrari, O.F.; Knapp, R.M.; Silberberg, I.H.; Thompson, T.W.


    In order to satisfy the objective of outlining the preliminary plan and schedules as well as obtaining representative costs for drilling a geopressured geothermal well the guidelines have been applied to one of the possible test sites identified by the Resource Assessment Phase I of the project. The specific site is the Armstrong lease in the Candelaria Field in Kenedy County, Texas. Offset well information including bit records, drilling fluid programs, formation pressure encountered and casing programs for the Armstrong No. 20 and No. 22 wells are presented. Based on this information a preliminary drilling program has been prepared. Well completion and production considerations were taken into account in the preparation of the drilling program. A brief description of drilling operations is also included to clarify the terminology used.

  16. An innovative drilling system

    Nees, J.; Dickinson, E.; Dickinson, W.; Dykstra, H.


    The principal project objectives were the following: To demonstrate the capability of the Ultrashort Radius Radial System to drill and complete multiple horizontal radials in a heavy oil formation which had a production history of thermal operations. To study the effects that horizontal radials have on steam placement at specific elevations and on reducing gravity override. To demonstrate that horizontal radials could be utilized for cyclic production, i.e. for purposes of oil production as well as for steam injection. Each of these objectives was successfully achieved in the project. Early production results indicate that radials positively influenced cyclic performance. This report documents those results. 15 refs., 29 figs., 1 tab.

  17. Global Networks of Trade and Bits

    Riccaboni, Massimo; Schiavo, Stefano


    Considerable efforts have been made in recent years to produce detailed topologies of the Internet. Although Internet topology data have been brought to the attention of a wide and somewhat diverse audience of scholars, so far they have been overlooked by economists. In this paper, we suggest that such data could be effectively treated as a proxy to characterize the size of the "digital economy" at country level and outsourcing: thus, we analyse the topological structure of the network of trade in digital services (trade in bits) and compare it with that of the more traditional flow of manufactured goods across countries. To perform meaningful comparisons across networks with different characteristics, we define a stochastic benchmark for the number of connections among each country-pair, based on hypergeometric distribution. Original data are thus filtered by means of different thresholds, so that we only focus on the strongest links, i.e., statistically significant links. We find that trade in bits displays...

  18. Fault diagnosis of downhole drilling incidents using adaptive observers and statistical change detection

    Willersrud, Anders; Blanke, Mogens; Imsland, Lars


    Downhole abnormal incidents during oil and gas drilling causes costly delays, any may also potentially lead to dangerous scenarios. Dierent incidents willcause changes to dierent parts of the physics of the process. Estimating thechanges in physical parameters, and correlating these with changes...... are assessed and optimized using data-based learning to obtainthresholds for hypothesis testing. Data from a 1400 m horizontal ow loop isused to test the method, and successful diagnosis of the incidents drillstringwashout (pipe leakage), lost circulation, gas in ux, and drill bit plugging aredemonstrated....

  19. 2-bit Flip Mutation Elementary Fitness Landscapes

    Langdon, William


    Genetic Programming parity is not elementary. GP parity cannot be represented as the sum of a small number of elementary landscapes. Statistics, including fitness distance correlation, of Parity's fitness landscape are calculated. Using Walsh analysis the eigen values and eigenvectors of the Laplacian of the two bit flip fitness landscape are given and a ruggedness measure for elementary landscapes is proposed. An elementary needle in a haystack (NIH) landscape is g...

  20. Blind One-Bit Compressive Sampling


    notation and recalling some background from convex analysis . For the d-dimensional Euclidean space Rd, the class of all lower semicontinuous convex...compressed sensing, Applied and Computational Harmonic Analysis , 27 (2009), pp. 265 – 274. [3] P. T. Boufounos and R. G. Baraniuk, 1-bit compressive sensing...Convergence analysis of the algorithm is presented. Our approach is to obtain a sequence of optimization problems by successively approximating the ℓ0

  1. Hydrogenated Black Diamond: An Electrical Study

    Williams, O.A.; Jackman, R.B. [Electronic and Electrical Engineering, University College London, Torrington Place, London, WC1E 7JE (United Kingdom); Nebel, C.E. [Walter Schottky Institut, Technische Universitaet Muenchen, Am Coulombwall, 85748 Garching (Germany)


    Hydrogen surface conductivity has been a controversial subject since its discovery. Initial plasma treatments on single crystal diamond and polycrystalline diamond have lead to the widespread use of this material in active electronics. However, ''Black'' polycrystalline diamond, usually termed ''Thermal Management Grade'', shows carrier concentration and mobility values similar to both white polycrystalline diamond and single crystal material. Schottky contacts have also been fabricated and show promising characteristics. Black diamond can be grown considerably faster than white diamond and is hence much cheaper. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  2. 30 CFR 33.34 - Drilling test.


    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drilling test. 33.34 Section 33.34 Mineral... MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.34 Drilling test. (a) A drilling test shall consist of drilling a set of 10 test holes,...

  3. Recent R&D in Drilling Equipment

    Sun Zuchen; Huang Zhiqian


    @@ Situation for Drilling Equipment Technical performance of drilling equipment and perfection of supporting systems hold the key to drilling safety, technical procedure development and drilling cost. In the end of the 1980s, the stituation for drilling equipment was not optimistic in China because of poor technical performance, low-level supporting system and scarcity of electric-driven rigs.

  4. Rate Control for MPEG-4 Bit Stream

    王振洲; 李桂苓


    For a very long time video processing dealt exclusively with fixed-rate sequences of rectangular shaped images. However, interest has been recently moving toward a more flexible concept in which the subject of the processing and encoding operations is a set of visual elements organized in both time and space in a flexible and arbitrarily complex way. The moving picture experts group (MPEG-4) standard supports this concept and its verification model (VM) encoder has adopted scalable rate control (SRC) as the rate control scheme, which is based on the spatial domain and compatible with constant bit rate (CBR) and variable bit rate (VBR). In this paper,a new rate control algorithm based on the DCT domain instead of the pixel domain is presented. More-over, macroblock level rate control scheme to compute the quantization step for each macroblock has been adopted. The experimental results show that the new algorithm can achieve a much better result than the original one in both peak signal-to-noise ratio (PSNR) and the coding bits, and that the new algorithm is more flexible than test model 5 (TM5) rate control algorithm.

  5. NSC 800, 8-bit CMOS microprocessor

    Suszko, S. F.


    The NSC 800 is an 8-bit CMOS microprocessor manufactured by National Semiconductor Corp., Santa Clara, California. The 8-bit microprocessor chip with 40-pad pin-terminals has eight address buffers (A8-A15), eight data address -- I/O buffers (AD(sub 0)-AD(sub 7)), six interrupt controls and sixteen timing controls with a chip clock generator and an 8-bit dynamic RAM refresh circuit. The 22 internal registers have the capability of addressing 64K bytes of memory and 256 I/O devices. The chip is fabricated on N-type (100) silicon using self-aligned polysilicon gates and local oxidation process technology. The chip interconnect consists of four levels: Aluminum, Polysi 2, Polysi 1, and P(+) and N(+) diffusions. The four levels, except for contact interface, are isolated by interlevel oxide. The chip is packaged in a 40-pin dual-in-line (DIP), side brazed, hermetically sealed, ceramic package with a metal lid. The operating voltage for the device is 5 V. It is available in three operating temperature ranges: 0 to +70 C, -40 to +85 C, and -55 to +125 C. Two devices were submitted for product evaluation by F. Stott, MTS, JPL Microprocessor Specialist. The devices were pencil-marked and photographed for identification.

  6. 1/N Perturbations in Superstring Bit Models

    Thorn, Charles B


    We develop the 1/N expansion for stable string bit models, focusing on a model with bit creation operators carrying only transverse spinor indices a=1,...,s. At leading order (1/N=0), this model produces a (discretized) lightcone string with a "transverse space' of $s$ Grassmann worldsheet fields. Higher orders in the 1/N expansion are shown to be determined by the overlap of a single large closed chain (discretized string) with two smaller closed chains. In the models studied here, the overlap is not accompanied with operator insertions at the break/join point. Then the requirement that the discretized overlap have a smooth continuum limit leads to the critical Grassmann "dimension" of s=24. This "protostring", a Grassmann analog of the bosonic string, is unusual, because it has no large transverse dimensions. It is a string moving in one space dimension and there are neither tachyons nor massless particles. The protostring, derived from our pure spinor string bit model, has 24 Grassmann dimensions, 16 of wh...

  7. Verilog Implementation of 32-Bit CISC Processor

    P.Kanaka Sirisha


    Full Text Available The Project deals with the design of the 32-Bit CISC Processor and modeling of its components using Verilog language. The Entire Processor uses 32-Bit bus to deal with all the registers and the memories. This Processor implements various arithmetic, logical, Data Transfer operations etc., using variable length instructions, which is the core property of the CISC Architecture. The Processor also supports various addressing modes to perform a 32-Bit instruction. Our Processor uses Harvard Architecture (i.e., to have a separate program and data memory and hence has different buses to negotiate with the Program Memory and Data Memory individually. This feature enhances the speed of our processor. Hence it has two different Program Counters to point to the memory locations of the Program Memory and Data Memory.Our processor has ‘Instruction Queuing’ which enables it to save the time needed to fetch the instruction and hence increases the speed of operation. ‘Interrupt Service Routine’ is provided in our Processor to make it address the Interrupts.

  8. Diamonds: Exploration, mines and marketing

    Read, George H.; Janse, A. J. A. (Bram)


    The beauty, value and mystique of exceptional quality diamonds such as the 603 carat Lesotho Promise, recovered from the Letseng Mine in 2006, help to drive a multi-billion dollar diamond exploration, mining and marketing industry that operates in some 45 countries across the globe. Five countries, Botswana, Russia, Canada, South Africa and Angola account for 83% by value and 65% by weight of annual diamond production, which is mainly produced by four major companies, De Beers, Alrosa, Rio Tinto and BHP Billiton (BHPB), which together account for 78% by value and 72% by weight of annual diamond production for 2007. During the last twelve years 16 new diamond mines commenced production and 4 re-opened. In addition, 11 projects are in advanced evaluation and may begin operations within the next five years. Exploration for diamondiferous kimberlites was still energetic up to the last quarter of 2008 with most work carried out in Canada, Angola, Democratic Republic of the Congo (DRC) and Botswana. Many kimberlites were discovered but no new economic deposits were outlined as a result of this work, except for the discovery and possible development of the Bunder project by Rio Tinto in India. Exploration methods have benefitted greatly from improved techniques of high resolution geophysical aerial surveying, new research into the geochemistry of indicator minerals and further insights into the formation of diamonds and the relation to tectonic/structural events in the crust and mantle. Recent trends in diamond marketing indicate that prices for rough diamonds and polished goods were still rising up to the last quarter of 2008 and subsequently abruptly sank in line with the worldwide financial crisis. Most analysts predict that prices will rise again in the long term as the gap between supply and demand will widen because no new economic diamond discoveries have been made recently. The disparity between high rough and polished prices and low share prices of publicly

  9. Genetic Types of Diamond Mineralization

    A.A.MARAKUSHEV; 桑隆康; 等


    The paper describes the proposed models of diamond formation both in meteorites and in kimberlite and lamproite bodies.metamorphic complexes and explosive-ring structures ("astroblemes"),The diamond distribution in meteorites(chondrites,iron meteorites and ureilites)is restricted to taente-kamasite phase.The diamond generation here is tied up with the first stage of evolution of the planets,This stage is characterized by high pressure of hydrogen. leading to the formation of the planet envelope,The second stage of planet evolution began with the progressive imopoverishment of their atmospheres in hydrogen due to its predominant emission into the space and to progressive development of oxidative conditions.The model appears to have proved the relict nature of diamond mineraolization in meteorites.Diamond and other high-pressure minerals(its"satellites") were crystallized without any exception in the early intratelluric stages of peridotite and eclogite-pyroxenite magma evolution just before the magma intrusion into the higher levels of the mantle and crust where diamond is not thermodynamically stable,The ultramafic intrusive bodies(bearing rich relict diamonds)in the dase of a platform paaear to be the substrata for the formation of kimberlite-lamproite magma chambers as a result of magmatic replacement.The model explains the polyfacial nature of diamondiferous eclotgites,pyroxenites and peridotites and discusses the process of inheritance of their diamond mineralization by kimberlites and lamproites.Dimond oproductivity of metamorthic complexes is originated by the inheritance of their diamonds from the above-mentioned primary diamondiferous rocks.Large diamondiferous explosive-ring structures were formed by high-energy endogenic explosion of fluid which came from the Earth's core.This high energy differs endogenic impactogenesis from explosive volcanism.It proceeds at very high temperature to create diaplectic galsses(monomineral pseudomorphs)-the product of

  10. Optimal parameters to avoid thermal necrosis during bone drilling: A finite element analysis.

    Mediouni, Mohamed; Schlatterer, Daniel R; Khoury, Amal; Von Bergen, Tobias; Shetty, Sunil H; Arora, Manit; Dhond, Amit; Vaughan, Neil; Volosnikov, Alexander


    The drilling bone may potentially cause excessive frictional heat, which can lead to local bone necrosis. This heat generation and local necrosis has been suggested to contribute to the resorption of bone around the placed screws, ending in loss of screw purchase in the bone and inadvertent loosening and/or the bone-implant construct. In vivo studies on this subject have inherent obstacles not the least of which is controlling the variables and real time bone temperature data acquisition. Theoretical models can be generated using computer software and the inclusion of known constants for the mechanical properties of metal and bone. These known Data points for the variables (drill bit and bone) enables finite element analysis of various bone drilling scenarios. An elastic-plastic three-dimensional (3D) acetabular bone mode was developed and finite element model analysis (FEA) was applied to various simulated drilling procedures. The FEA results clearly indicate that the depth of drilling and the drill speed both have a significant effect on the temperature during drilling procedures. The reduction of the feeding speed leads to a reduction in bone temperature. Our data suggests that reducing the feeding speed regardless of RPMs and pressure applied could be a simple useful and effective way to reduce drilling temperatures. This study is the first step in helping any surgeon who drills bone and places screws to better understand the ideal pressure to apply and drill speed to employ and advance rate to avoid osteonecrosis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

  11. Wetting evaluation of silver based braze alloys onto zirconia metalized with reactive elements for application in oil well drill bots; Avaliacao do molhamento de ligas de adicao a base de prata sobre zirconia polida e metalizada com elementos ativos para aplicacao em brocas de perfuracao de pocos de petroleo

    Pereira, J.C.; Silva, J.M.; Santos, P.R.F.; Nascimento, R.M.; Martinelli, A.E. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Engenharia de Materiais], Email:; Pimenta, J.S. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica


    Drill bits with hard ceramic inserts are often used on drilling operations. The cutting and crushing action of rocks will produce failures in the tricone bits, which are related to wear; total or partial rupture of the drill bit body or even the inserts; thermal shock and corrosion. The research of better drill bits with ceramic inserts thermally more stable and mechanically stronger, will lead to an increase of their lifetime, and so reducing costs of substitution and maintenance. In the present work, some silver based braze alloys were melted onto zirconia YSZ substrates metallized or not with active metals. inside a furnace with vacuum of 10{sup -5} mbar to evaluate the wetting behavior. The system with AgCuTi and the non metallized YSZ ceramic, showed low contact angles and stable interfaces, which may be appropriate for brazing metal/ceramic parts. (author)

  12. Raman study of diamond-based abrasives, and possible artefacts in detecting UHP microdiamond

    Nasdala, Lutz; Steger, Simon; Reissner, Claudia


    Raman spectral characteristics of a range of diamond-based abrasives (powders and sprays) and drilling and cutting tools, originating from preparation laboratories worldwide, are presented. Some abrasives show strong broadening of the main diamond band [FWHM (full width at half band-maximum) > 5 cm- 1] accompanied by strong band-downshift (ν˜ = 1316-1330 cm- 1). Others are characterised by moderate band broadening (FWHM = 1.8-5 cm- 1) at rather regular band position (ν˜ = 1331-1333 cm- 1). In addition we found that a ;fresh; abrasive and its used analogue may in some cases show vast differences in their Raman spectra. The Raman parameters of diamond-based abrasives overlap widely with Raman parameters of UHP (ultra-high pressure) microdiamond. It is hence impossible to assign diamond detected in a geological specimen to either an introduced artefact or a genuine UHP relict, from the Raman spectrum alone. Raman is an excellent technique for the detection of minute amounts of diamond; however it does not provide conclusive evidence for the identification of UHP microdiamond. The latter requires thorough verification, for instance by optical microscopy or, if doubts cannot be dispelled, transmission electron microscopy.

  13. Reversible n-Bit to n-Bit Integer Haar-Like Transforms

    Senecal, J; Duchaineau, M; Joy, K I


    We introduce a wavelet-like transform similar to the Haar transform, but with the properties that it packs the results into the same number of bits as the original data, and is reversible. Our method, called TLHaar, uses table lookups to replace the averaging, differencing, and bit shifting performed in a Haar IntegerWavelet Transform (IWT). TLHaar maintains the same coefficient magnitude relationships for the low- and high-pass coefficients as true Haar, but reorders them to fit into the same number of bits as the input signal, thus eliminating the sign bit that is added to the Haar IWT output coefficients. Eliminating the sign bit avoids using extra memory and speeds the transform process. We tested TLHaar on a variety of image types, and when compared to the Haar IWT TLHaar is significantly faster. For image data with lines or hard edges TLHaar coefficients compress better than those of the Haar IWT. Due to its speed TLHaar is suitable for streaming hardware implementations with fixed data sizes, such as DVI channels.

  14. Are diamond nanoparticles cytotoxic?

    Schrand, Amanda M; Huang, Houjin; Carlson, Cataleya; Schlager, John J; Omacr Sawa, Eiji; Hussain, Saber M; Dai, Liming


    Finely divided carbon particles, including charcoal, lampblack, and diamond particles, have been used for ornamental and official tattoos since ancient times. With the recent development in nanoscience and nanotechnology, carbon-based nanomaterials (e.g., fullerenes, nanotubes, nanodiamonds) attract a great deal of interest. Owing to their low chemical reactivity and unique physical properties, nanodiamonds could be useful in a variety of biological applications such as carriers for drugs, genes, or proteins; novel imaging techniques; coatings for implantable materials; and biosensors and biomedical nanorobots. Therefore, it is essential to ascertain the possible hazards of nanodiamonds to humans and other biological systems. We have, for the first time, assessed the cytotoxicity of nanodiamonds ranging in size from 2 to 10 nm. Assays of cell viability such as mitochondrial function (MTT) and luminescent ATP production showed that nanodiamonds were not toxic to a variety of cell types. Furthermore, nanodiamonds did not produce significant reactive oxygen species. Cells can grow on nanodiamond-coated substrates without morphological changes compared to controls. These results suggest that nanodiamonds could be ideal for many biological applications in a diverse range of cell types.

  15. About creation of machines for rock destruction with formation of apertures of various cross-sections

    Zhukov, I. A.; Dvornikov, L. T.; Nikitenko, S. M.


    The article presents the results of the experimental research of the high strength rock destruction by a bladeless tool. Rational circuit designs of disposing of indenters in the impact part of the drill bits and a diamond tool are justified. New constructive solutions of reinforcing bladeless drill bits, which allow drilling blast-holes of the various cross-section, are shown.

  16. Great Progress of Drilling Technology in China

    Li Kexiang


    @@ A great progress has been made in drilling technology in China from 1986 to 1990 by popularizing research achievements and emphasizing high economic efficiency of exploration and development, high quality of drilling engineering, high drilling rate and formation damage prevention.

  17. 浅谈大井眼钻井技术%Discussion on the big hole drilling technology



    Limited by the drilling bit size,broken area of big hole size(311.1 mm and above) is large,and it has the problems of single bit type,mechanical and hydraulic energy shortage,slow drilling speed,high cost,.From the angle of formation drill ability and bit selection,the use of PDC bits,improved mechanical and hydraulic parameters,optimization of assembly,the use of advanced tools and process is put forward for improvement of the big hole drilling speed.In the windy city district,hutubi gas storage application shows that it can significantly improve the mechanical drilling rate,shorten the drilling cycle.%大井眼(Φ311.1mm及以上尺寸)钻井由于受钻头尺寸大、破碎面积大、钻头类型单一、机械及水力能量不足等因素的影响,钻井速度慢,成本高,从地层可钻性研究及钻头选型、PDC钻头的使用、强化机械及水力参数、优化钻具组合、采用先进工具及工艺等方面提出了提高大井眼钻井速度的途径,在风城地区、呼图壁储气库的应用表明,能显著提高机械钻速,缩短钻井周期。

  18. Integrated diamond networks for quantum nanophotonics

    Hausmann, Birgit J M; Quan, Qimin; Maletinsky, Patrick; McCutcheon, Murray; Choy, Jennifer T; Babinec, Tom M; Kubanek, Alexander; Yacoby, Amir; Lukin, Mikhail D; Loncar, Marko


    Diamond is a unique material with exceptional physical and chemical properties that offers potential for the realization of high-performance devices with novel functionalities. For example diamond's high refractive index, transparency over wide wavelength range, and large Raman gain are of interest for the implementation of novel photonic devices. Recently, atom-like impurities in diamond emerged as an exceptional system for quantum information processing, quantum sensing and quantum networks. For these and other applications, it is essential to develop an integrated nanophotonic platform based on diamond. Here, we report on the realization of such an integrated diamond photonic platform, diamond on insulator (DOI), consisting of a thin single crystal diamond film on top of an insulating silicon dioxide/silicon substrate. Using this approach, we demonstrate diamond ring resonators that operate in a wide wavelength range, including the visible (630nm) and near-infrared (1,550nm). Finally, we demonstrate an int...

  19. The Design of Diamond Compton Telescope

    Hibino, Kinya; Okuno, Shoji; Yajima, Kaori; Uchihori, Yukio; Kitamura, Hisashi; Takashima, Takeshi; Yokota, Mamoru; Yoshida, Kenji


    We have developed radiation detectors using the new synthetic diamonds. The diamond detector has an advantage for observations of "low/medium" energy gamma rays as a Compton telescope. The primary advantage of the diamond detector can reduce the photoelectric effect in the low energy range, which is background noise for tracking of the Compton recoil electron. A concept of the Diamond Compton Telescope (DCT) consists of position sensitive layers of diamond-striped detector and calorimeter layer of CdTe detector. The key part of the DCT is diamond-striped detectors with a higher positional resolution and a wider energy range from 10 keV to 10 MeV. However, the diamond-striped detector is under development. We describe the performance of prototype diamond detector and the design of a possible DCT evaluated by Monte Carlo simulations.

  20. Anodic bonding of diamond to glass

    Fuentes, R. [Materials and Technologies Corp., Poughkeepsie, NY (United States); Trolio, L.M. [Geo-Centers, Inc., Fort Washington, MD (United States); Butler, J.E. [Naval Research Lab., Washington, DC (United States)


    A method is described for anodically bonding smooth nanocrystalline diamond films to glass substrates to form extremely flat diamond membranes with the smoothest side available of patterning absorber structures to form masks for proximity focused x-ray lithography.

  1. A new route to process diamond wires

    Marcello Filgueira


    Full Text Available We propose an original route to process diamond wires, denominated In Situ Technology, whose fabrication involves mechanical conformation processes, such as rotary forging, copper tubes restacking, and thermal treatments, such as sintering and recrystallisation of a bronze 4 wt.% diamond composite. Tensile tests were performed, reaching an ultimate tensile strength (UTS of 230 MPa for the diameter of Æ = 1.84 mm. Scanning electron microscopy showed the diamond crystals distribution along the composite rope during its manufacture, as well as the diamond adhesion to the bronze matrix. Cutting tests were carried out with the processed wire, showing a probable performance 4 times higher than the diamond sawing discs, however its probable performance was about 5 to 8 times less than the conventional diamond wires (pearl system due to the low abrasion resistance of the bronze matrix, and low adhesion between the pair bronze-diamond due to the use of not metallised diamond single crystals.

  2. Fluorocarbon Contamination from the Drill on the Mars Science Laboratory: Potential Science Impact on Detecting Martian Organics by Sample Analysis at Mars (SAM)

    Eigenbrode, J. L.; McAdam, A.; Franz, H.; Freissinet, C.; Bower, H.; Floyd, M.; Conrad, P.; Mahaffy, P.; Feldman, J.; Hurowitz, J.; Evans, J.; Anderson, M.; Jandura, L.; Brown, K.; Logan, C.; Kuhn, S.; Anderson, R.; Beegle, L.; Limonadi, D.; Rainen, R.; Umland, J.


    Polytetrafluoroethylene (PTFE or trade name: Teflon by Dupont Co.) has been detected in rocks drilled during terrestrial testing of the Mars Science Laboratory (MSL) drilling hardware. The PTFE in sediments is a wear product of the seals used in the Drill Bit Assemblies (DBAs). It is expected that the drill assembly on the MSL flight model will also shed Teflon particles into drilled samples. One of the primary goals of the Sample Analysis at Mars (SAM) instrument suite on MSL is to test for the presence of martian organics in samples. Complications introduced by the potential presence of PTFE in drilled samples to the SAM evolved gas analysis (EGA or pyrolysisquadrupole mass spectrometry, pyr-QMS) and pyrolysis- gas chromatography mass spectrometry (Pyr- GCMS) experiments was investigated.

  3. Simulation of the Cuttings Cleaning During the Drilling Operation

    Hussain H. Al-Kayiem


    Full Text Available Problem statement: Oil well cleaning is the ability of a drilling fluid to suspend and transport drilled cuttings from the down hole (bit face to the surface. The cleaning performance was affected by many factors such as fluid viscosity, annular flow velocity, angle of inclination and drill cuttings size and shape and. Approach: Navier-Stoke equations, the continuity equation and the power law of non-Newtonian viscosity model were adopted to establish the mathematical model of the cutting transport process in the annulus of the well. The constants of the power law model were evaluated experimentally for three different mud types. The CFD simulation to solve the governing equations was carried out by using FLUENT commercial code. The specifications of the particles, the pumping head and feeding conditions were obtained from a drilling site in Sudan. Results: Simulation of the mud flow in the annulus had shown that in spite of the laminar nature of the flow, the velocity profile was flattening over wide area of the annulus. Such condition was referred to as fog flow and was preferable to produce uniform drag distribution to lift the particles without rotation during the transportation process. The analysis had been conducted for various mud charging rates ranging from 600-900 GPM, in 30° diverted orientation well. The investigation of cuttings size was conducted for 2.54, 4.45 and 7 mm. Also, the effect of the cuttings shape with 1, 0.9 and 0.85 was investigated and it was found that higher sphereicity have better cleaning efficiency. Conclusion: The analyses revealed that for 30° diverted orientation; the effective cleaning performance was achieved when the drilling mud charging was higher than 800 GPM for all types of tested cuttings. The simulation results revealed that there was a significant effect of the cuttings size on the cuttings transport. Fine particles are the easiest to clean out.

  4. Advances in core drilling technology

    Holdsworth, G.

    Some notable technical advances in drill design were reported at the meeting, held in Canada August 30-September 1, 1982, at the University of Calgary. Chief amongst these was a battery powered, computer assisted electromechanical core drill which has recently been used by the Danes in Greenland to continuously core to the base of the ice sheet at 2038 m. This is the deepest coring operation so far on the Greenland ice sheet. (The record for deep glacier drilling is held by the U.S. Army Cold Regions Research and Engineering Laboratory for the continuous coring through 2164 m of ice to bedrock at Byrd Station, Antarctica, in 1968). In early 1982, a current Soviet core drilling operation was reported to be at a depth of 2000 m at Vostok station, Antarctica, where the total ice thickness is about 4000 m; the goal of core drilling the entire ice thickness there could be achieved before the end of 1983.

  5. The Marskhod Egyptian Drill Project

    Shaltout, M. A. M.

    We describe a possible participation of Egypt in a future Mars rover Mission. It was suggested that Egypt participate through involvement in the design, building and testing of a drill to obtain sub-surface samples. The Space Research Institute of the Russian Academy of Sciences (IKI), formally invited the Egyptian Ministry of Scientific Research to study the concept for potential use on the Russian Mars 2001 Mission. As one of the objectives of the Marskhod mission was the analysis of sub-surface samples, a drilling mechanism in the payload would be essential. The Egyptian expertise in drill development is associated with the archaeological exploration of the Pyramids. A sophisticated drilling system perforated limestone to a depth of 2 m without the use of lubricants or cooling fluids that might have contaminated the Pit's environment. This experience could have been applied to a drill development Mars 2001 mission, which was unfortunately canceled due to economic problems.

  6. Auto-Gopher-II: an autonomous wireline rotary-hammer ultrasonic drill

    Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Bar-Cohen, Yoseph; Jackson, Shannon; Chesin, Jacob; Zacny, Kris; Paulsen, Gale L.; Mellerowicz, Bolek; Kim, Daniel


    Developing technologies that would enable future NASA exploration missions to penetrate deeper into the subsurface of planetary bodies for sample collection is of great importance. Performing these tasks while using minimal mass/volume systems and with low energy consumption is another set of requirements imposed on such technologies. A deep drill, called Auto-Gopher II, is currently being developed as a joint effort between JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher II is a wireline rotary-hammer drill that combines formation breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted auger bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that has been developed as an adaptable tool for many drilling and coring applications. The USDC uses an intermediate free-flying mass to transform high frequency vibrations of a piezoelectric transducer horn tip into sonic hammering of the drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher and then integrated into a rotary hammer device to develop the Auto-Gopher-I. The lessons learned from these developments are being integrated into the development of the Auto- Gopher-II, an autonomous deep wireline drill with integrated cuttings and sample management and drive electronics. Subsystems of the wireline drill are being developed in parallel at JPL and Honeybee Robotics Ltd. This paper presents the development efforts of the piezoelectric actuator, cuttings removal and retention flutes and drive electronics.

  7. A novel bit-quad-based Euler number computing algorithm.

    Yao, Bin; He, Lifeng; Kang, Shiying; Chao, Yuyan; Zhao, Xiao


    The Euler number of a binary image is an important topological property in computer vision and pattern recognition. This paper proposes a novel bit-quad-based Euler number computing algorithm. Based on graph theory and analysis on bit-quad patterns, our algorithm only needs to count two bit-quad patterns. Moreover, by use of the information obtained during processing the previous bit-quad, the average number of pixels to be checked for processing a bit-quad is only 1.75. Experimental results demonstrated that our method outperforms significantly conventional Euler number computing algorithms.

  8. A novel bit-quad-based Euler number computing algorithm

    Yao, Bin; He, Lifeng; Kang, Shiying; Chao, Yuyan; Xiao ZHAO


    The Euler number of a binary image is an important topological property in computer vision and pattern recognition. This paper proposes a novel bit-quad-based Euler number computing algorithm. Based on graph theory and analysis on bit-quad patterns, our algorithm only needs to count two bit-quad patterns. Moreover, by use of the information obtained during processing the previous bit-quad, the average number of pixels to be checked for processing a bit-quad is only 1.75. Experimental results ...

  9. Adaptive Power and Bit Allocation in Multicarrier Systems

    HUO Yong-qing; PENG Qi-cong; SHAO Huai-zong


    We present two adaptive power and bit allocation algorithms for multicarrier systems in a frequency selective fading environment. One algorithm allocates bit based on maximizing the channel capacity, another allocates bit based on minimizing the bit-error-rate(BER). Two algorithms allocate power based on minimizing the BER. Results show that the proposed algorithms are more effective than Fischer's algorithm at low average signal-to-noise ration (SNR). This indicates that our algorithms can achieve high spectral efficiency and high communication reliability during bad channel state. Results also denote the bit and power allocation of each algorithm and effects of the number of subcarriers on the BER performance.

  10. Ohmic contacts to semiconducting diamond

    Zeidler, James R.; Taylor, M. J.; Zeisse, Carl R.; Hewett, C. A.; Delahoussaye, Paul R.


    Work was carried out to improve the electron beam evaporation system in order to achieve better deposited films. The basic system is an ion pumped vacuum chamber, with a three-hearth, single-gun e-beam evaporator. Four improvements were made to the system. The system was thoroughly cleaned and new ion pump elements, an e-gun beam adjust unit, and a more accurate crystal monitor were installed. The system now has a base pressure of 3 X 10(exp -9) Torr, and can easily deposit high-melting-temperature metals such as Ta with an accurately controlled thickness. Improved shadow masks were also fabricated for better alignment and control of corner contacts for electrical transport measurements. Appendices include: A Thermally Activated Solid State Reaction Process for Fabricating Ohmic Contacts to Semiconducting Diamond; Tantalum Ohmic Contacts to Diamond by a Solid State Reaction Process; Metallization of Semiconducting Diamond: Mo, Mo/Au, and Mo/Ni/Au; Specific Contact Resistance Measurements of Ohmic Contracts to Diamond; and Electrical Activation of Boron Implanted into Diamond.

  11. Automatic evaluation of drilling fluid properties

    Hansen, Eirik


    This thesis is structured in two main parts. First part covers the fundamental role of drilling fluid in the drilling process. It provides a description of the mud circulating system for conventional drilling operations, outlines the basic composition of drilling fluids, and describes the main functions and properties of drilling fluids. Furthermore it describes the current testing procedures and equipment and illustrates how testing is used in the evaluation of drilling fluid ...

  12. Dual gradient drilling - simulations during connection operations

    Time, André


    As oilfields are ageing and depleting, operators are forced to start searching for oil in more hostile environments. These new environments can introduce new drilling challenges. Prospects like ultra deep water reservoirs and depleted offshore reservoirs are difficult to drill with conventional drilling. This has lead the industry to developing the Dual Gradient Drilling (DGD) system. DGD is an unconventional drilling method and it is classified as a Managed Pressure Drilling ...

  13. Fiscal 1997 survey report. Survey on the innovative well drilling technology; 1997 nendo chosa hokokusho. Kakushinteki kosei kussaku gijutsu ni kansuru chosa



    In the geothermal drilling, reduction of the cost of well drilling is an important subject for technical development. The geothermal resource development tends to be made at higher temperatures and at deeper wells. In the present drilling technology, the cost is rising with the exponentially increasing depth and temperature, and there is also occurring the technical limit. Accordingly, the survey clarified the limit of the present drilling technology/cost to point out the research trend of the drilling technology as substitute for the present one, possibilities of the introduction, and the R and D target and subjects. As to latest drilling systems abroad and in Japan, the following were surveyed to study and extract promising technologies and systems: improvement/application of drilling equipment/materials (enhancement of heat resistance of the main drilling equipment, etc., cooling effects of top drive, heat resistance verification of MWD tools, PDM, tricone bits, multi-stage cementing tools, etc.), heightening of drilling rates, trend surveys of slim hole drilling, control drilling, well maintenance/workover, and well design technology. 68 refs., 73 figs., 40 tabs.

  14. Raman spectral research on MPCVD diamond film

    YAN Yan; ZHANG Shulin; ZHAO Xinsheng; HAN Yisong; HOU Li


    Raman spectra of MPCVD diamond film have been studied. Based on the resonance size selection effect, we think that there is no nano-crystalline diamond in the sample and the Raman peak at 1145 cm-1 can not be considered as the characteristic peak of nano-crystalline diamond though it has been used as the characteristic peak of nano-crystalline diamond widely for many years.

  15. Medical applications of diamond particles & surfaces

    Roger J Narayan


    Full Text Available Diamond has been considered for use in several medical applications due to its unique mechanical, chemical, optical, and biological properties. In this paper, methods for preparing synthetic diamond surfaces and particles are described. In addition, recent developments involving the use of diamond in prostheses, sensing, imaging, and drug delivery applications are reviewed. These developments suggest that diamond-containing structures will provide significant improvements in the diagnosis and treatment of medical conditions over the coming years.

  16. Diamond and diamond-like films for transportation applications

    Perez, J.M.


    This section is a compilation of transparency templates which describe the goals of the Office of Transportation Materials (OTM) Tribology Program. The positions of personnel on the OTM are listed. The role and mission of the OTM is reviewed. The purpose of the Tribology Program is stated to be `to obtain industry input on program(s) in tribology/advanced lubricants areas of interest`. The objective addressed here is to identify opportunities for cost effective application of diamond and diamond-like carbon in transportation systems.

  17. Preliminary petrographic and geophysical interpretations of the exploratory geothermal drill hole and core, Redstone, New Hampshire

    Hoag, R.B. Jr.; Stewart, G.W.


    A 3000 foot diamond drill hole was drilled in the Conway Granite in Redstone, New Hampshire. A comprehensive detailed petrographic and physical study of this core was made. The purpose of this study is to supply a sound data base for future geothermal and uranium-thorium studies of the drill core. An estimate of the heat flow potential of the Redstone drill hole gives a heat flow of 1.9 HFU. If only the red phase of the Conway Granite had been intersected the heat flow may have been as much as 2.7 HFU, reaching a temperature of 260/sup 0/C at 6 km. The drill hole intersected four lithologies; the green and red phase of the Conway Granite, the Albany quartz syenite and a medium-grained, hastingsite-biotite granite. The red phase has the highest and most irregular radioactivity. The irregularity is mainly due to minor variations in lithology. The drill core intersected several alteration zones up to a thickness of 150 feet. These alteration zones represent passage of low to medium temperature fluids which might have been mineralized. The Conway Granite has the physical and chemical characteristics necessary for the formation of vein type uranium deposits. The presence of unexplained radiometric anomalies lends support to the existence of such deposits.

  18. Ultratough single crystal boron-doped diamond

    Hemley, Russell J [Carnegie Inst. for Science, Washington, DC ; Mao, Ho-Kwang [Carnegie Inst. for Science, Washington, DC ; Yan, Chih-Shiue [Carnegie Inst. for Science, Washington, DC ; Liang, Qi [Carnegie Inst. for Science, Washington, DC


    The invention relates to a single crystal boron doped CVD diamond that has a toughness of at least about 22 MPa m.sup.1/2. The invention further relates to a method of manufacturing single crystal boron doped CVD diamond. The growth rate of the diamond can be from about 20-100 .mu.m/h.

  19. 8 Bit RISC Processor Using Verilog HDL

    Ramandeep Kaur


    Full Text Available RISC is a design philosophy to reduce the complexity of instruction set that in turn reduces the amount of space, cycle time, cost and other parameters taken into account during the implementation of the design. The advent of FPGA has enabled the complex logical systems to be implemented on FPGA. The intent of this paper is to design and implement 8 bit RISC processor using FPGA Spartan 3E tool. This processor design depends upon design specification, analysis and simulation. It takes into consideration very simple instruction set. The momentous components include Control unit, ALU, shift registers and accumulator register.

  20. Diamonds at the golden point

    Katarina Anthony


    Alongside the CMS Pixel Luminosity Telescope (PLT) – installed last month (see here) – lie diamond detectors. No ordinary gems, these lab-grown diamonds will be playing a vital role in Run 2: differentiating signals from collision products with those from the beam background.   The BCM detector's green "c-shaped" printed circuit board is mounted on the PLT/BCM carbon-fibre carriage ready for installation. Earlier this year, the CMS BRIL project installed beam condition monitors (BCM) at the heart of the CMS detector. Designed to measure the online luminosity and beam background as close as possible to the LHC beam pipe, the BCMs use radiation-hard diamonds to differentiate between background and collision signals. The BCM also protects the CMS silicon trackers from damaging beam losses, by aborting the beam if the signal currents measured are above an acceptable threshold. These new BCMs are designed with Run 2 bunches in mind. &ldq...

  1. Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill

    Badescu, Mircea; Sherrit, Stewart; Bao, Xiaogi; Bar-Cohen, Yoseph; Chen, Beck


    Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet, as well as, the search for water and other resources. A deep corer, called Auto-Gopher, is currently being developed as a joint effort of the JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher is a wire-line rotary-hammer drill that combines rock breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) that has been developed as an adaptable tool for many of drilling and coring applications. The USDC uses an intermediate free-flying mass to transform the high frequency vibrations of the horn tip into a sonic hammering of a drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher. The lessons learned from testing the ice gopher were implemented into the design of the Auto-Gopher by inducing a rotary motion onto the fluted coring bit. A wire-line version of such a system would allow penetration of significant depth without a large increase in mass. A laboratory version of the corer was developed in the NDEAA lab to determine the design and drive parameters of the integrated system. The design configuration lab version of the design and fabrication and preliminary testing results are presented in this paper

  2. Pulsed laser deposition of metallic films on the surface of diamond particles for diamond saw blades

    Jiang Chao [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, WuHan, Hubei 430074 (China); Luo Fei [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, WuHan, HuBei 430074 (China); Long Hua [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Hu Shaoliu [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Li Bo [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Wang Youqing [State Key Laboratory of Laser Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)]. E-mail:


    Ti or Ni films have been deposited on the diamond particle surfaces by pulsed laser deposition. Compressive resistance of the uncoated and coated diamond particles was measured, respectively, in the experiments. The compressive resistance of the Ti-coated diamonds particles was found much higher than that of the uncoated ones. It increased by 39%. The surface morphology is observed by the metallography microscope. The surface of the uncoated diamonds particles had many hollows and flaws, while the surface of Ni-coated diamond particles was flat and smooth, and the surface of Ti-coated diamond particles had some metal masses that stood out of the surface of the Ti-coated film. The components of the metallic films of diamond particles were examined by X-ray diffractometry (XRD). TiC was found formed on the Ti-coated diamond surface, which resulted in increased surface bonding strength between the diamond particles and the Ti films. Meanwhile, TiC also favored improving the bonding strength between the coated diamond particles and the binding materials. Moreover, the bending resistance of the diamond saw blade made of Ti-coated diamond was drastically higher than that of other diamond saw blades, which also played an important role in improving the blade's cutting ability and lifetime. Therefore, it was most appropriate that the diamond saw blade was made of Ti-coated diamond particles rather than other materials.

  3. Diamonds on Diamond: structural studies at extreme conditions on the Diamond Light Source.

    McMahon, M I


    Extreme conditions (EC) research investigates how the structures and physical and chemical properties of materials change when subjected to extremes of pressure and temperature. Pressures in excess of one million times atmospheric pressure can be achieved using a diamond anvil cell, and, in combination with high-energy, micro-focused radiation from a third-generation synchrotron such as Diamond, detailed structural information can be obtained using either powder or single-crystal diffraction techniques. Here, I summarize some of the research drivers behind international EC research, and then briefly describe the techniques by which high-quality diffraction data are obtained. I then highlight the breadth of EC research possible on Diamond by summarizing four examples from work conducted on the I15 and I19 beamlines, including a study which resulted in the first research paper from Diamond. Finally, I look to the future, and speculate as to the type of EC research might be conducted at Diamond over the next 10 years.

  4. Drilling miniature holes, Part III

    Gillespie, L.K.


    Miniature components for precision electromechanical mechanisms such as switches, timers, and actuators typically require a number of small holes. Because of the precision required, the workpiece materials, and the geometry of the parts, most of these holes must be produced by conventional drilling techniques. The use of such techniques is tedious and often requires considerable trial and error to prevent drill breakage, minimize hole mislocation and variations in hole diameter. This study of eight commercial drill designs revealed that printed circuit board drills produced better locational and size repeatability than did other drills when centerdrilling was not used. Boring holes 1 mm in dia, or less, as a general rule did not improve hole location in brass or stainless steel. Hole locations of patterns of 0.66-mm holes can be maintained within diametral positional tolerance if setup misalignments can be eliminated. Size tolerances of +- 3.8 can be maintained under some conditions when drilling flat plates. While these levels of precision are possible with existing off-the-shelf drills, they may not be practical in many cases.

  5. Establishing nuclear facility drill programs



    The purpose of DOE Handbook, Establishing Nuclear Facility Drill Programs, is to provide DOE contractor organizations with guidance for development or modification of drill programs that both train on and evaluate facility training and procedures dealing with a variety of abnormal and emergency operating situations likely to occur at a facility. The handbook focuses on conducting drills as part of a training and qualification program (typically within a single facility), and is not intended to included responses of personnel beyond the site boundary, e.g. Local or State Emergency Management, Law Enforcement, etc. Each facility is expected to develop its own facility specific scenarios, and should not limit them to equipment failures but should include personnel injuries and other likely events. A well-developed and consistently administered drill program can effectively provide training and evaluation of facility operating personnel in controlling abnormal and emergency operating situations. To ensure the drills are meeting their intended purpose they should have evaluation criteria for evaluating the knowledge and skills of the facility operating personnel. Training and evaluation of staff skills and knowledge such as component and system interrelationship, reasoning and judgment, team interactions, and communications can be accomplished with drills. The appendices to this Handbook contain both models and additional guidance for establishing drill programs at the Department`s nuclear facilities.

  6. Where the "it from bit" come from?

    Foschini, Luigi


    In his 1989 essay, John Archibald Wheeler has tried to answer the eternal question of existence. He did it by searching for links between information, physics, and quanta. The main concept emerging from his essay is that "every physical quantity, every it, derives its ultimate significance from bits, binary yes-or-no indications". This concept has been summarized in the catchphrase "it from bit". In the Wheeler's essay, it is possible to read several times the echoes of the philosophy of Niels Bohr. The Danish physicist has pointed out how the quantum and relativistic physics - forcing us to abandon the anchor of the visual reference of common sense - have imposed a greater attention to the language. Bohr did not deny the physical reality, but recognizes that there is always need of a language no matter what a person wants to do. To put it as Carlo Sini, language is the first toolbox that man has at hands to analyze the experience. It is not a thought translated into words, because to think is to operate with...

  7. Digital word width reducing system for PCM video signal processing - feeds less significant bits to one-bit coder and then combined with more significant bits



    Abstract of NL 8902368 (A) The system converts a PCM input signal. It has a series of digital words, each K bits long at a predetermined repetition frequency converted into a PCM output signal (16) comprising a series of digital words each L bits long, where L is less than K. The system includes a

  8. Method for machining steel with diamond tools

    Casstevens, John M.


    The present invention is directed to a method for machining optical quality inishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  9. Diamond Sensors for Energy Frontier Experiments

    Schnetzer, Steve


    We discuss the use of diamond sensors in high-energy, high-i ntensity collider experiments. Re- sults from diamond sensor based beam conditions monitors in the ATLAS and CMS experiments at the CERN Large Hadron Collider (LHC) are presented and pla ns for diamond based luminosity monitors for the upcoming LHC run are described. We describe recent measurements on single crystal diamond sensors that indicate a polarization effec t that causes a reduction of charge col- lection efficiency as a function of particle flux. We conclude by describing new developments on the promising technology of 3D diamond sensors.

  10. Nanocrystalline diamond films for biomedical applications

    Pennisi, Cristian Pablo; Alcaide, Maria


    performance of nanocrystalline diamond films is reviewed from an application-specific perspective, covering topics such as enhancement of cellular adhesion, anti-fouling coatings, non-thrombogenic surfaces, micropatterning of cells and proteins, and immobilization of biomolecules for bioassays. In order......Nanocrystalline diamond films, which comprise the so called nanocrystalline diamond (NCD) and ultrananocrystalline diamond (UNCD), represent a class of biomaterials possessing outstanding mechanical, tribological, and electrical properties, which include high surface smoothness, high corrosion...... resistance, chemical inertness, superior electrochemical behavior, biocompatibility, and nontoxicity. These properties have positioned the nanocrystalline diamond films as an attractive class of materials for a range of therapeutic and diagnostic applications in the biomedical field. Consequently...

  11. Transparent nanocrystalline diamond coatings and devices

    Sumant, Anirudha V.; Khan, Adam


    A method for coating a substrate comprises producing a plasma ball using a microwave plasma source in the presence of a mixture of gases. The plasma ball has a diameter. The plasma ball is disposed at a first distance from the substrate and the substrate is maintained at a first temperature. The plasma ball is maintained at the first distance from the substrate, and a diamond coating is deposited on the substrate. The diamond coating has a thickness. Furthermore, the diamond coating has an optical transparency of greater than about 80%. The diamond coating can include nanocrystalline diamond. The microwave plasma source can have a frequency of about 915 MHz.

  12. Electron Microscopy of Natural and Epitaxial Diamond

    Posthill, J. B.; George, T.; Malta, D. P.; Humphreys, T. P.; Rudder, R. A.; Hudson, G. C.; Thomas, R. E.; Markunas, R. J.


    Semiconducting diamond films have the potential for use as a material in which to build active electronic devices capable of operating at high temperatures or in high radiation environments. Ultimately, it is preferable to use low-defect-density single crystal diamond for device fabrication. We have previously investigated polycrystalline diamond films with transmission electron microscopy (TEM) and scanning electron microscopy (SEM), and homoepitaxial films with SEM-based techniques. This contribution describes some of our most recent observations of the microstructure of natural diamond single crystals and homoepitaxial diamond thin films using TEM.

  13. Selected Bibliography II-Diamond Surface Chemistry


    34Scanning Tunneling Microscopy of Polished Diamond Surfaces" JNL: Appl. Surf. Sci. REF: 62(4) (1992) 263-8 91 AUTHOR: Vazquez L., Martin -Gago J. A...Absorption in Semiconducting Synthetic Diamond" JNL: Physical Review REF: 140 (1965) A1272 AUTHOR: Keown R. TITLE: "Energy Bands in Diamond" JNL...34Determination of Optical Constant of Diamond Thin Films" JNL: Proc. SPIE-Int. Soc. Opt. Eng. REF: 1759(Diamond Opt. V) (1992) 218-23 AUTHOR: Fazzio A., Martins

  14. Diamond Ablators for Inertial Confinement Fusion

    Biener, J; Mirkarimi, P B; Tringe, J W; Baker, S L; Wang, Y M; Kucheyev, S O; Teslich, N E; Wu, K J; Hamza, A V; Wild, C; Woerner, E; Koidl, P; Bruehne, K; Fecht, H


    Diamond has a unique combination of physical properties for the inertial confinement fusion ablator application, such as appropriate optical properties, high atomic density, high yield strength, and high thermal conductivity. Here, we present a feasible concept to fabricate diamond ablator shells. The fabrication of diamond capsules is a multi-step process, which involves diamond chemical vapor deposition on silicon mandrels followed by polishing, microfabrication of holes, and removing of the silicon mandrel by an etch process. We also discuss the pros and cons of coarse-grained optical quality and nanocrystalline chemical vapor deposition diamond films for the ablator application.

  15. Wavelets as q-bits and q-bit states as wavelets

    Steblinski, Pawel; Blachowicz, Tomasz


    In this short report it is argued that by the use of wavelets formalism it is possible to describe the q-bit state. The wavelet formalism address the real-valued physical signals, for example, obtained during typical physical measurements.

  16. 导向PDC钻头设计及其在临盘地区的应用%Steerable PDC Bit Design and Its Application in Linpan Area

    罗恒荣; 邹德永; 曹继飞; 唐玉响


    针对常规PDC钻头在胜利油田临盘地区定向井钻进过程中存在的工具面不稳定、井斜角和方位角难以控制、滑动钻进时钻速较低等问题,研究分析了PDC钻头的剖面形状、切削结构、保径设计等对钻头导向性能的影响规律,在此基础上,研制出一种适合临盘地区地层特性的BTM115H型导向PDC钻头.该型PDC钻头采用浅内锥、双圆弧剖面形状,特殊双重切削布齿、短保径设计和侧向力平衡设计,能够有效提高钻头的导向性能和机械钻速.多口定向井的现场应用效果表明,BTM115H型导向PDC钻头在定向钻进过程中,工具面可控性好,复合钻井速度和定向机械钻速较常规PDC钻头都有大幅度提高,为临盘地区的定向井快速钻进提供了有力保障.%In order to resolve the problems caused by conventional PDC bit in drilling directional wells in Linpan Area of Shengli Oilfield, such as the instable tool face, difficulty to control inclination and azimuth, low drilling speed etc,a new steerable PDC bit was developed based on the analysis of bit profile,cutting structure,gauge design for steerable capability. The new steerable PDC bit was designed with shallow inner cone, double circular section, double cutter structure and short gauge design, and its stability and steerable capacity was improved. The field application shows that the new bit has more stability for controlling tool face,has higher drilling speed and better borehole quality than that of conventional PDC bits. The new bit ensures quick directional drilling in Linpan Area.

  17. Analysis of bone formation after cranial osteotomies with a high-speed drill.

    Barone, C M; Jimenez, D F; Yule, G J; Strauch, B


    Ten New Zealand white 22-week-old rabbits were divided into two groups of five each. The Midas Rex drill with a C-1 drill bit was used to make a full-thickness sagittal osteotomy 2 cm in length. A B-5 bit and footplate attachment were used to make a 2-cm linear osteotomy parallel to the first. Four drill holes 1 mm in diameter were made over the nasal bones on the ipsilateral side. In Group A animals, half of the skull had no irrigation; the other half of the skull was irrigated with room temperature saline. In Group B animals half of the skull was irrigated with iced saline irrigation; the other half of the skull was irrigated with room temperature irrigation fluid, and the osteotomy sites were filled with bone wax. Specimens were harvested at 8 weeks and evaluated grossly and histologically. The results showed that all the drill holes closed in the nasal bones regardless of the type of irrigation used or whether bone wax was used. Iced saline irrigation and room temperature irrigation had similar positive effects on bone formation in contrast to the no-irrigation group, which had inferior bone formation. Bone wax appeared also to have a detrimental effect on bone formation.

  18. Discontinuities effect on drilling condition and performance of selected rocks in Nigeria

    Adebayo Babatunde⇑; Bello Wasiu Ademola


    The study examined joint discontinuity spacing effect on drilling condition and performance in selected rocks in Ilorin and Ibese areas, Nigeria. Five samples for each rock type (gneiss and limestone) were tested in the laboratory for chemical, physical and mechanical properties. Dip direction and joint spacing were measured using compass clinometers. The chemical composition was determined using X-ray Fluores-cence (XRF) spectrometer. The results show that gneiss has SiO2 of 61.88%and limestone has CaO content of 52.3%. The average dry density of gneiss and limestone are 2.6 and 2.39 g/cm3, respectively. The uniaxial compressive strength of gneiss and limestone are 195 and 93.83 MPa, respectively. These rocks are classified as strong and moderately strong rock. Gneiss and limestone have mean joint discontinuity spacing of 0.79 and 0.25 m, which classified them as moderate and wide joint spacing respectively. Joint spacing was correlated with specific energy, bit wear and uniaxial compressive using Statistical Package for Social Science (SPSS). The regression model has multiple coefficient of correlation of R2=0.791 and R2=0.995 for gneiss and limestone, respectively. The variation in joint spacing could be attributed to spe-cific energy, bit wear and uniaxial compressive strength which affect drilling condition and performance. Ultimately, as joint spacing gets closer, the drilling velocity increases, drill string will be stable.

  19. Analysis on the nitrogen drilling accident of Well Qionglai 1 (I: Major inducement events of the accident

    Yingfeng Meng


    Full Text Available Nitrogen drilling in poor tight gas sandstone should be safe because of very low gas production. But a serious accident of fire blowout occurred during nitrogen drilling of Well Qionglai 1. This is the first nitrogen drilling accident in China, which was beyond people's knowledge about the safety of nitrogen drilling and brought negative effects on the development of gas drilling technology still in start-up phase and resulted in dramatic reduction in application of gas drilling. In order to form a correct understanding, the accident was systematically analyzed, the major events resulting in this accident were inferred. It is discovered for the first time that violent ejection of rock clasts and natural gas occurred due to the sudden burst of downhole rock when the fractured tight gas zone was penetrated during nitrogen drilling, which has been named as “rock burst and blowout by gas bomb”, short for “rock burst”. Then all the induced events related to the rock burst are as following: upthrust force on drilling string from rock burst, bridging-off formed and destructed repeatedly at bit and centralizer, and so on. However, the most direct important event of the accident turns out to be the blockage in the blooie pipe from rock burst clasts and the resulted high pressure at the wellhead. The high pressure at the wellhead causes the blooie pipe to crack and trigged blowout and deflagration of natural gas, which is the direct presentation of the accident.

  20. Design and experimental performance verification of a thermal property test-bed for lunar drilling exploration

    Zhang Tao; Zhao Zeng; Liu Shuting; Li Jinglin; Ding Xilun; Yin Shen; Wang Guoxin; Lai Xiaoming


    Chinese Chang’e lunar exploration project aims to collect and return subsurface lunar soil samples at a minimum penetration depth of 2 m in 2017. However, in contrast to those on the Earth, automated drilling and sampling missions on the Moon raise the risk of burning bits. Test-beds are required for testing the thermal properties of drill tools in a lunar environment. In this paper, a novel temperature measuring method based on thermocouples and a slip ring was proposed. Furthermore, a data acquisition system for a drilling process was designed. A vacuous, cryogenic, and anhydrous soil environment simulating the lunar surface was established. A drilling test-bed that can reach a depth of 2.2 m was developed. A control strategy based on online monitoring signals was proposed to improve the drilling performance. Vacuum and non-vacuum experiments were performed to test the temperature rising effect on drill tools. When compared with the non-vacuum experiment, the vacuum temperature rise resulted in a 12 ?C increase. These experimental results provide significant support for Chinese lunar exploration missions.