Single Piezo-Actuator Rotary-Hammering Drill

Science.gov (United States)

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

2011-01-01

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

The Auto-Gopher Deep Drill

Science.gov (United States)

Badescu, Mircea

2014-01-01

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.

The Effects of Bit Wear on Respirable Silica Dust, Noise and Productivity: A Hammer Drill Bench Study.

Science.gov (United States)

Carty, Paul; Cooper, Michael R; Barr, Alan; Neitzel, Richard L; Balmes, John; Rempel, David

2017-07-01

Hammer drills are used extensively in commercial construction for drilling into concrete for tasks including rebar installation for structural upgrades and anchor bolt installation. This drilling task can expose workers to respirable silica dust and noise. The aim of this pilot study was to evaluate the effects of bit wear on respirable silica dust, noise, and drilling productivity. Test bits were worn to three states by drilling consecutive holes to different cumulative drilling depths: 0, 780, and 1560 cm. Each state of bit wear was evaluated by three trials (nine trials total). For each trial, an automated laboratory test bench system drilled 41 holes 1.3 cm diameter, and 10 cm deep into concrete block at a rate of one hole per minute using a commercially available hammer drill and masonry bits. During each trial, dust was continuously captured by two respirable and one inhalable sampling trains and noise was sampled with a noise dosimeter. The room was thoroughly cleaned between trials. When comparing results for the sharp (0 cm) versus dull bit (1560 cm), the mean respirable silica increased from 0.41 to 0.74 mg m-3 in sampler 1 (P = 0.012) and from 0.41 to 0.89 mg m-3 in sampler 2 (P = 0.024); levels above the NIOSH recommended exposure limit of 0.05 mg m-3. Likewise, mean noise levels increased from 112.8 to 114.4 dBA (P < 0.00001). Drilling productivity declined with increasing wear from 10.16 to 7.76 mm s-1 (P < 0.00001). Increasing bit wear was associated with increasing respirable silica dust and noise and reduced drilling productivity. The levels of dust and noise produced by these experimental conditions would require dust capture, hearing protection, and possibly respiratory protection. The findings support the adoption of a bit replacement program by construction contractors. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Electromagnetic Hammer for Metalworking

Science.gov (United States)

Anderson, S. A.; Brunet, F.; Dowd, A.; Durham, R.; Ezell, J.; Gorr, G.; Hartley, D.; Jackson, F.; Marchand, J.; Macfarlane, W.;

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

Science.gov (United States)

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

2012-01-01

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

Impact Driver With Integral Sliding Hammer

Science.gov (United States)

Wallace, Bilby J.

1987-01-01

Tool combines impact driver with sliding dead-blow hammer. Used for any purpose for which ordinary impact driver used; tightening fasteners or driving starter holes for drill. Tool protects user from accidental injury and surrounding equipment from damage that might occur from ordinary arm-wielded hammer. Especially useful in underwater work.

Advanced Percussive Drilling Technology for Geothermal Exploration and Development

Energy Technology Data Exchange (ETDEWEB)

Su, Jiann [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Raymond, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Prasad, Somuri [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wolfer, Dale [Atlas-Copco Secoroc LLC, Fagersta (Sweden)

2017-06-12

Percussive hammers are a promising advance in drilling technology for geothermal since they rely upon rock reduction mechanisms that are well-suited for use in the hard, brittle rock characteristic of geothermal formations. The project research approach and work plan includes a critical path to development of a high-temperature (HT) percussive hammer using a two phase approach. The work completed in Phase I of the project demonstrated the viability of percussive hammers and that solutions to technical challenges in design, material technology, and performance are likely to be resolved. Work completed in Phase II focused on testing the findings from Phase I and evaluating performance of the materials and designs at high operating temperatures. A high-operating temperature (HOT) drilling facility was designed, built, and used to test the performance of the DTH under extreme conditions. Results from the testing indicate that a high-temperature capable hammer can be developed and is a viable alternative for use in the driller’s toolbox.

Tests of HAMMER (original) and HAMMER-TECHNION systems with critical experiments

International Nuclear Information System (INIS)

Santos, A. dos

1986-01-01

Performances of the reactor cell codes HAMMER (original) and HAMMER-TECHNION were tested against experimental results of critical benchmarks. The option made was the utilization of consistent methodologies so that only the NIT (Nordheim Integral Technique) was utilized in the HAMMER-TECHNION. All differences encountered in the analysis made with these systems can be attributed to their basic nuclear data library. Five critical benchmarks was utilized on this study. Surprisingly, the performance of the original HAMMER system was betterthan that of the HAMMER-TECHNION. (Author) [pt

DE-FOA-EE0005502 Advanced Percussive Drilling Technology for Geothermal Exploration and Development Phase II Report.

Energy Technology Data Exchange (ETDEWEB)

Su, Jiann-Cherng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Raymond, David W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Prasad, Somuri V. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wolfer, Dale R. [Atlas-Copco Secoroc, LLC, Fagersta (Sweden)

2017-05-01

Percussive hammers are a promising advance in drilling technology for geothermal since they rely upon rock reduction mechanisms that are well-suited for use in the hard, brittle rock characteristic of geothermal formations. The project research approach and work plan includes a critical path to development of a high-temperature (HT) percussive hammer using a two- phase approach. The work completed in Phase I of the project demonstrated the viability of percussive hammers and that solutions to technical challenges in design, material technology, and performance are likely to be resolved. Work completed in Phase II focused on testing the findings from Phase I and evaluating performance of the materials and designs at high- operating temperatures. A high-operating temperature (HOT) drilling facility was designed, built, and used to test the performance of the DTH under extreme conditions. Results from the testing indicate that a high-temperature capable hammer can be developed and is a viable alternative for user in the driller's toolbox.

A Study of Specific Fracture Energy at Percussion Drilling

Science.gov (United States)

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

2014-08-01

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.

A Study of Specific Fracture Energy at Percussion Drilling

International Nuclear Information System (INIS)

Shadrina A; Krets V; Saruev L; Kabanova T

2014-01-01

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

Optimal Force Control of Vibro-Impact Systems for Autonomous Drilling Applications

Science.gov (United States)

Aldrich, Jack B.; Okon, Avi B.

2012-01-01

The need to maintain optimal energy efficiency is critical during the drilling operations performed on future and current planetary rover missions (see figure). Specifically, this innovation seeks to solve the following problem. Given a spring-loaded percussive drill driven by a voice-coil motor, one needs to determine the optimal input voltage waveform (periodic function) and the optimal hammering period that minimizes the dissipated energy, while ensuring that the hammer-to-rock impacts are made with sufficient (user-defined) impact velocity (or impact energy). To solve this problem, it was first observed that when voice-coil-actuated percussive drills are driven at high power, it is of paramount importance to ensure that the electrical current of the device remains in phase with the velocity of the hammer. Otherwise, negative work is performed and the drill experiences a loss of performance (i.e., reduced impact energy) and an increase in Joule heating (i.e., reduction in energy efficiency). This observation has motivated many drilling products to incorporate the standard bang-bang control approach for driving their percussive drills. However, the bang-bang control approach is significantly less efficient than the optimal energy-efficient control approach solved herein. To obtain this solution, the standard tools of classical optimal control theory were applied. It is worth noting that these tools inherently require the solution of a two-point boundary value problem (TPBVP), i.e., a system of differential equations where half the equations have unknown boundary conditions. Typically, the TPBVP is impossible to solve analytically for high-dimensional dynamic systems. However, for the case of the spring-loaded vibro-impactor, this approach yields the exact optimal control solution as the sum of four analytic functions whose coefficients are determined using a simple, easy-to-implement algorithm. Once the optimal control waveform is determined, it can be used

Water hammer research in networks

OpenAIRE

Anželika Jurkienė; Mindaugas Rimeika

2015-01-01

Formation of water hammer, its consequences and possible protection measures are rarely topics, however the problem is significant. Water hammer can form in water supply and pressurized sewage networks, for various reasons. The article presents short theory of water hammer and methodology for calculation of specific parameters. Research of water hammer was performed in real water supply and sewer networks of country. Simulation of water hammer was carried out by turning on and off water pumps...

Dynamic Analysis of Hammer Mechanism "Twin Hammer" of Impact Wrench

Science.gov (United States)

Konečný, M.; Slavík, J.

This paper describes function of the hammer mechanism "Twin hammer" the impact wrench, calculation of dynamic forces exerted on the mechanism and determining the contact pressures between the parts of the mechanism. The modelling of parts was performed in system Pro ENGINEER—standard. The simulation and finding dynamic forces was performed in advanced module Pro ENGINEER—mechanism design and finding contacts pressures in modul Pro ENGENEER—mechanica.

Optimizing drilling performance using a selected drilling fluid

Science.gov (United States)

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.

2011-04-19

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.

Water hammer research in networks

Directory of Open Access Journals (Sweden)

Anželika Jurkienė

2015-10-01

Full Text Available Formation of water hammer, its consequences and possible protection measures are rarely topics, however the problem is significant. Water hammer can form in water supply and pressurized sewage networks, for various reasons. The article presents short theory of water hammer and methodology for calculation of specific parameters. Research of water hammer was performed in real water supply and sewer networks of country. Simulation of water hammer was carried out by turning on and off water pumps in pumping station. Successful measurement of water hammer depends on accuracy of the measurement equipment, therefore during the research surge wave fluctuations were measured with especially high resolution pressure meters. Detailed analysis of water hammer and selection of protecting equipment hydraulic model of water supply network was created. Protection against water hammer helps to avoid breaking of the water network and extend operation time.

Water hammer

International Nuclear Information System (INIS)

Anon.

1979-01-01

The overall NRC program for the resolution of the water hammer issue is divided into four tasks: water hammer summary reports; revision of CP and OL review procedures; water hammer positions for operating reactors; and water hammer safety studies

Deep drilling KLX 02. Drilling and documentation of a 1700 m deep borehole at Laxemar, Sweden

Energy Technology Data Exchange (ETDEWEB)

Andersson, O [VBB VIAK AB, Malmoe (Sweden)

1994-08-01

In this report the preparation and execution of the deep core drilling KLX 02 is described. The hole was drilled with the wireline methods, NQ dimension (diameter 76 mm), to a final depth of 1700.5 m. Prior to core drilling a diameter 215 mm pilot hole was pre drilled to 200 m with controlled hammer drilling (DTH). In this hole casing and air-lift equipment was installed with the aim to support the circulation of drilling fluid. During core drilling there was a measurement of major drilling parameters and drilling fluid in and out of hole. As a fluid tracer uranine was used. Each 300 m of core drilling air-lift pump tests were performed. After completion a flow-meter log was run to finalize the project phase. It can be concluded that both the pre drilling and core drilling methods used proved to be successful. No severe technical problem occurred. However, potential risks have been pointed at in the report. The air-lift system functioned only partly and has to be modified for further use. Also the technique for monitoring of drilling parameters needs improvement as does the method for air-lift pump tests with packer. The organisation model for planning and realization functioned satisfactory and can be recommended for similar future projects. 9 refs, numerous tabs and figs.

Deep drilling KLX 02. Drilling and documentation of a 1700 m deep borehole at Laxemar, Sweden

International Nuclear Information System (INIS)

Andersson, O.

1994-08-01

In this report the preparation and execution of the deep core drilling KLX 02 is described. The hole was drilled with the wireline methods, NQ dimension (diameter 76 mm), to a final depth of 1700.5 m. Prior to core drilling a diameter 215 mm pilot hole was pre drilled to 200 m with controlled hammer drilling (DTH). In this hole casing and air-lift equipment was installed with the aim to support the circulation of drilling fluid. During core drilling there was a measurement of major drilling parameters and drilling fluid in and out of hole. As a fluid tracer uranine was used. Each 300 m of core drilling air-lift pump tests were performed. After completion a flow-meter log was run to finalize the project phase. It can be concluded that both the pre drilling and core drilling methods used proved to be successful. No severe technical problem occurred. However, potential risks have been pointed at in the report. The air-lift system functioned only partly and has to be modified for further use. Also the technique for monitoring of drilling parameters needs improvement as does the method for air-lift pump tests with packer. The organisation model for planning and realization functioned satisfactory and can be recommended for similar future projects. 9 refs, numerous tabs and figs

Fundamental Research on Percussion Drilling: Improved rock mechanics analysis, advanced simulation technology, and full-scale laboratory investigations

Energy Technology Data Exchange (ETDEWEB)

Michael S. Bruno

2005-12-31

drilling tests, as well as single impact tests, have been designed and executed. Both Berea sandstone and Mancos shale samples are used. In single impact tests, three impacts are sequentially loaded at the same rock location to investigate rock response to repetitive loadings. The crater depth and width are measured as well as the displacement and force in the rod and the force in the rock. Various pressure differences across the rock-indentor interface (i.e. bore pressure minus pore pressure) are used to investigate the pressure effect on rock penetration. For hammer drilling tests, an industrial fluid hammer is used to drill under both underbalanced and overbalanced conditions. Besides calibrating the modeling tool, the data and cuttings collected from the tests indicate several other important applications. For example, different rock penetrations during single impact tests may reveal why a fluid hammer behaves differently with diverse rock types and under various pressure conditions at the hole bottom. On the other hand, the shape of the cuttings from fluid hammer tests, comparing to those from traditional rotary drilling methods, may help to identify the dominant failure mechanism that percussion drilling relies on. If so, encouraging such a failure mechanism may improve hammer performance. The project is summarized in this report. Instead of compiling the information contained in the previous quarterly or other technical reports, this report focuses on the descriptions of tasks, findings, and conclusions, as well as the efforts on promoting percussion drilling technologies to industries including site visits, presentations, and publications. As a part of the final deliveries, the 3D numerical model for rock mechanics is also attached.

Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

Science.gov (United States)

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

2009-01-01

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

Project T100 -- Hazardous Materials Management and Emergency Response Training Center (HAMMER)

International Nuclear Information System (INIS)

Norton, C.E.

1994-01-01

The scope of this Quality Assurance Program Plan (QAPP) is to provide a system of Quality Assurance reviews and verifications on the design and construction of the Hazardous Materials Management and Emergency Response (HAMMER) Training Center, project 95L-EWT-100 at Hanford. The reviews and verifications will be on activities associated with design, procurement, and construction of the HAMMER project which includes, but is not limited to earthwork, placement of concrete, laying of rail, drilling of wells, water and sewer line fabrication and installation, communications systems, fire protection/detection systems, line tie-ins, building and mock-up (prop) construction, electrical, instrumentation, pump and valves and special coatings

Water-hammer experimental set-up and water-hammer experimental study for new types of check valve applied to PWR

International Nuclear Information System (INIS)

Liu Hanxun.

1985-01-01

This paper describes a self-designed constant temperature water-hammer shock test rig with stainless steel loop in which deionized water is used as working medium. To conduct water-hammer shock simulation tests for the countercurrent phenomenon occurred in the process of shutting, stopping, parallelling and switching the coolant loops of nuclear reactor, a specially designed four-way switching valve and its pneumatic mechanism are used. Water-hammer experimental study is performed for two types of PWR's nonshock check valve with diameter of 150 mm and 200 mm simultaneously. Transient performance of the shock waves, magnitude of their peaks and durations of their fluctuation, is obtained. Some analyses for existing calculational method on water-hammer are made

Muscle fibre type composition and body composition in hammer throwers.

Science.gov (United States)

Terzis, Gerasimos; Spengos, Konstantinos; Kavouras, Stavros; Manta, Panagiota; Georgiadis, Giorgos

2010-01-01

Aim of the present study was to describe the muscle fibre type composition and body composition of well-trained hammer throwers. Six experienced hammer throwers underwent the following measurements: one repetition maximum in squat, snatch, and clean, standing broad jump, backward overhead shot throw and the hammer throw. Dual x-ray absorptiometry was used for body composition analysis. Fibre type composition and cross sectional area was determined in muscle biopsy samples of the right vastus lateralis. Eight physical education students served as a control group. One repetition maximum in squat, snatch and clean for the hammer throwers was 245 ± 21, 132 ± 13 and 165 ± 12kg, respectively. Lean body mass was higher in hammer throwers (85.9 ± 3. 9kg vs. 62.7 ± 5.1kg (p hammer throwers and 51 ± 8% in the control group (p Hammer throwers had significantly larger type IIA fibres (7703 ± 1171 vs. 5676 ± 1270μm(2), p Hammer throwing performance correlated significantly with lean body mass (r = 0.81, p hammer throwers have larger lean body mass and larger muscular areas occupied by type II fibres, compared with relatively untrained subjects. Moreover, it seems that the enlarged muscle mass of the hammer throwers contributes significantly to the hammer throwing performance. Key pointsWell-trained hammer throwers had increased lean body mass, higher type IIA muscle fibres cross sectional areas, as well as higher bone mineral density, compared to controls.Increased lean body mass was closely related with hammer throwing performance.The relative high percentage of type IIX muscle fibres in vastus lateralis in hammer throwers warrants further investigation.

Development of a jet-assisted polycrystalline diamond drill bit

Energy Technology Data Exchange (ETDEWEB)

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

1997-12-31

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.

Water hammer simulator

International Nuclear Information System (INIS)

Sinha, S.K.; Madia, J.; Dixon, S.

1995-01-01

The Consolidated Edison Company of New York, Inc. (Con Edison) has constructed a first-of-a-kind water hammer events simulator for use at its training center. The Learning Center, Con Edison's central training facility, intends to use the simulator as an educational tool to demonstrate the various mechanisms of the water hammer phenomenon to power plant designers, engineers and operators. The water hammer phenomenon has been studied extensively for the past 15 years for the nuclear industry. However, the acknowledge of the various water hammer mechanisms and the measures to prevent or mitigate water hammer have not been widely disseminated among the operators of fossil-fueled power plants. Con Edison personnel who operate the various generation stations and the New York City steam distribution systems are expected to benefit from the new simulator. Knowledge gained from interacting with the simulator will be very important in helping the Con Edison prevent, mitigate, or accommodate water hammer at its facilities. The water hammer simulator was fabricated in Con Edison's central machine shop. Details of the design and construction of the simulator were finalized in consultation with Creare, Inc., an engineering research firm, located in Hanover, New Hampshire. The simulator seeks to recreate the essential features of water hammer in steam mines following the buildup of cold (subcooled) water by condensation and steam-water interaction. This paper describes the fabrication, design, testing, and operation of the Con Edison water hammer simulator. A discussion of how Con Edison plans to use the facility at The Learning Center is included

Estimation of the effectiveness of the destruction of natural stone oversized by a hydraulic hammer

Directory of Open Access Journals (Sweden)

V.G. Kravets

2017-12-01

Full Text Available The experience of mining operations shows that even with the application of progressive methods of drilling, it is impossible to completely exclude the output of a large fraction (oversized. The percentage of oversized mass emissions from the blasting mass depending on the mining and geological conditions may vary from 5 to 20 percent. Catching an oversized piece into the receiving slit of the main crusher is associated with stopping the whole technological chain of the enterprise. Sharpening of oversized pieces of the work area during conducting of extraction or overturning works leads to a decrease in the efficiency of mining operations. Crushing of oversized materials to the required sizes can be carried out in an explosive way (by a bore or overhead charge or by non-explosive methods, most of which are based on mechanical destruction under the action of local dynamic stresses that cause stress exceeding the resistance of internal bonds in the rock. To date, manufacturers are offered many types of shock mechanisms, based on the transformation of various types of energy (from gravitational, to the energy of chemical processes into mechanical. For a number of reasons, mostly economic, to date, the most common way is the mechanical method of the destruction of oversized beams using hydraulic and hydro pneumatic hammer. That is why the work considers the main factors influencing the performance of the hydraulic hammer, among which – the specific energy consumption of the oversize and the main parameters of the hydraulic engine passport on the basis of the excavator. In the publication the power law of the hydraulic hammer changes in dependence of the size of the oversized. Also, the basic parameters of the JCB JS235 HD excavator passport are defined in the work with the use of the INDECO HP 1500 hammer hammer.

Drilling Performance of Rock Drill by High-Pressure Water Jet under Different Configuration Modes

Directory of Open Access Journals (Sweden)

Songyong Liu

2017-01-01

Full Text Available In the rock drilling progress, the resistant force results in tools failure and the low drilling efficiency; thus, it is necessary to reduce the tools failure and enhance the drilling efficiency. In this paper, different configuration modes of drilling performance assisted with water jet are explored based on the mechanism and experiment analysis of rock drilling assisted with water jet. Moreover, the rotary sealing device with high pressure is designed to achieve the axial and rotation movement simultaneously as well as good sealing effect under high-pressure water jet. The results indicate that the NDB and NFB have better effects on drilling performance compared with that of NSB. Moreover, the high-pressure water jet is helpful not only to reduce the drill rod deflection, but also to reduce the probability of drill rod bending and improve the drill rod service life.

An analysis of the relationship between the linear hammer speed and the thrower applied forces during the hammer throw for male and female throwers.

Science.gov (United States)

Brice, Sara M; Ness, Kevin F; Rosemond, Doug

2011-09-01

The purpose of this study was to investigate the relationship between the cable force and linear hammer speed in the hammer throw and to identify how the magnitude and direction of the cable force affects the fluctuations in linear hammer speed. Five male (height: 1.88 +/- 0.06 m; body mass: 106.23 +/- 4.83 kg) and five female (height: 1.69 +/- 0.05 m; body mass: 101.60 +/- 20.92 kg) throwers participated and were required to perform 10 throws each. The hammer's linear velocity and the cable force and its tangential component were calculated via hammer head positional data. As expected, a strong correlation was observed between decreases in the linear hammer speed and decreases in the cable force (normalised for hammer weight). A strong correlation was also found to exist between the angle by which the cable force lags the radius of rotation at its maximum (when tangential force is at its most negative) and the size of the decreases in hammer speed. These findings indicate that the most effective way to minimise the effect of the negative tangential force is to reduce the size of the lag angle.

Simulation of water hammer experiments using RELAP5 code

International Nuclear Information System (INIS)

Kaliatka, A.; Vaisnoras, M.

2005-01-01

The rapid closing or opening of a valve causes pressure transients in pipelines. The fast deceleration of the liquid results in high pressure surges upstream the valve, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increases. This phenomenon is called water hammer. The intensity of water hammer effects will depend upon the rate of change in the velocity or momentum. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the thermal-hydraulic system since, if the pressure induced exceeds the pressure range of a pipe given by the manufacturer, it can lead to the failure of the pipeline integrity. Due to its potential for damage of pipes, water hammer has been a subject of study since the middle of the nineteenth century. Many theoretical and experimental investigations were performed. The experimental investigation of the water hammer tests performed at Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) [1] and Cold Water Hammer experiment performed by Forschungszentrum Rossendorf (CWHTF) [2] should be mentioned. The UMSICHT facility in Oberhausen was modified in order to simulate a piping system and associated supports that are typical for a nuclear power plant [3]. The Cold water hammer experiment is interesting and instructive because it covers a wide spectrum of particularities. One of them is sub-cooled water interaction with condensing steam at the closed end of the vertical pipe at room temperature and corresponding saturation pressure [4]. In the paper, the capabilities of RELAP5 code to correctly represent the water hammer phenomenon are presented. Paper presents the comparison of RELAP5 calculated and measured at UMSICHT and CWHTF test facilities pressure transient values after the fast closure (opening) of valves. The analyses of rarefaction wave travels inside the pipe and condensation of vapour bubbles in the liquid column

Technical report for a fluidless directional drilling system demonstrated at Solid Waste Storage Area 6 shallow buried waste sites

International Nuclear Information System (INIS)

1995-09-01

The purpose of the research was to demonstrate a fluidless directional drilling and monitoring system (FDD) specifically tailored to address environmental drilling concerns for shallow buried wasted. The major concerns are related to worker exposure, minimizing waste generation, and confining the spread of contamination. The FDD is potentially applicable to Environmental Restoration (ER) activities for the Oak Ridge National Laboratory Waste Area Grouping 6 (WAG 6) shallow buried waste disposed in unlined trenches. Major ER activities for directional drilling are to develop a drilling system for leachate collection directly beneath trenches, and to provide localized control over leachate release to the environment. Other ER FDD activities could include vadose zone and groundwater monitoring of contaminant transport. The operational constraints pointed the research in the direction of purchasing a steerable impact hammer, or mole, manufactured by Steer-Rite Ltd. of Racine, Wisconsin. This drill was selected due to the very low cost ($25,000) associated with procuring the drill, steering module, instrumentation and service lines. The impact hammer is a self propelled drill which penetrates the soil by compacting cut material along the sidewalls of the borehole. Essentially, it forces its way through the subsurface. Although the pneumatic hammer exhausts compressed air which must be handled at the borehole collar, it does not generate soil cuttings or liquids. This is the basis for the term fluidless. A stub casing muffler was attached to the entrance hole for controlling exhaust gas and any airborne releases. Other environmental compliance modifications made to the equipment included operating the tool without lubrication, and using water instead of hydraulic fluid to actuate the steering fins on the tool

Analysis of water hammer phenomena in RBMK-1500 reactor main circulation circuit

International Nuclear Information System (INIS)

Kaliatka, A.; Uspuras, E.; Vaisnoras, M.

2006-01-01

Water hammer can occur in any thermal-hydraulic systems. Water hammer can reach pressure levels far exceeding the pressure range of a pipe given by the manufacturer, and it can lead to the failure of the pipeline integrity. In the past three decades, since a large number of water hammer events occurred in the light-water- reactor power plants, a number of comprehensive studies on the phenomena associated with water hammer events have been performed. There are three basic types of severe water hammer occurring at power plants that can result in significant plant damage: rapid valve operation events; void-induced water hammer; condensation-induced water hammer. Correct prediction of water hammer transients, is therefore of paramount importance for the safe operation of the plant. Therefore verifying of computer codes capability to simulate water hammer type transients is very important issue at performing of safety analyses for nuclear power plants. Verification of RELAP5/MOD3.3 code capability to simulate water hammer type transients employing the experimental investigations is presented. Experience gained from benchmarking analyses has been used at development of the detail RELAP5 code RBMK-1500 model for simulation of water hammer effects in reactor main circulation circuit. Analysis of reactor cooling system shows, that water hammers can occur in main circulation circuit of RBMK-1500 reactor in cases of: (1) Guillotine break of the inlet piping upstream of the Group Distribution Header and (2) Guillotine break of the pressure piping upstream the Main Circulation Pump check valve. Analysis of above mentioned accident scenarios is presented in this paper. First scenario of the accident potentially is more dangerous, because the pressure pulses influence not only the reactor cooling circuit, but also the piping of safety related system (Emergency Core Cooling System pipeline) connected to affected Group Distribution Header. The performed analysis using RELAP5 code

Maximum Water Hammer Sensitivity Analysis

OpenAIRE

Jalil Emadi; Abbas Solemani

2011-01-01

Pressure waves and Water Hammer occur in a pumping system when valves are closed or opened suddenly or in the case of sudden failure of pumps. Determination of maximum water hammer is considered one of the most important technical and economical items of which engineers and designers of pumping stations and conveyance pipelines should take care. Hammer Software is a recent application used to simulate water hammer. The present study focuses on determining significance of ...

Validity and Reliability of the Cycleops Hammer Cycle Ergometer.

Science.gov (United States)

Lillo-Bevia, José R; Pallarés, Jesús G

2017-11-28

To validate the new drive indoor trainer Hammer designed by Cycleops®. Eleven cyclists performed 44 randomized and counterbalanced graded exercise tests (100-500W), at 70, 85 and 100 rev.min -1 cadences, in seated and standing positions, on 3 different Hammer units, while a scientific SRM system continuously recorded cadence and power output data. No significant differences were detected between the three Hammer devices and the SRM for any workload, cadence, or pedalling condition (P value between 1.00 and 0.350), except for some minor differences (P 0.03 and 0.04) found in the Hammer 1 at low workloads, and for Hammer 2 and 3 at high workloads, all in seated position. Strong ICCs were found between the power output values recorded by the Hammers and the SRM (≥0.996; P=0.001), independently from the cadence condition and seated position. Bland-Altman analysis revealed low Bias (-5.5-3.8) and low SD of Bias (2.5-5.3) for all testing conditions, except marginal values found for the Hammer 1 at high cadences and seated position (9.6±6.6). High absolute reliability values were detected for the 3 Hammers (150-500W; CVreliable device to drive and measure power output in cyclists, providing an alternative to larger and more expensive laboratory ergometers, and allowing cyclists to use their own bicycle.

Condensation driven water hammer studies for feed water distribution pipe

International Nuclear Information System (INIS)

Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Longvinov, S.A.; Trunov, N.B.; Sitnik, Yu.K.

1997-01-01

Special T-shaped feedwater distribution pipes were installed in steam generators at the Loviisa (Finland) and Rovno (Russia) nuclear power plants. The new shape was tested in an extensive testing programme. Since the tubes frequently suffer from corrosion damage, large-scale water hammer experiments were performed on a model facility in 1996. The main objectives of the water hammer experiments were to find out the prevailing parameters leading to water hammers, as well as the sensitivity of hammering to boundary conditions. A water hammer may occur when the mass flow rate into the steam generator exceeds 6 kg/s and the temperature difference between steam generator and feedwater exceeds 100 degC. Visual experiments and stress analyses of the pipe were also carried out. The weakest part, the T-joint, may hold against such water hammers only for a limited time of the order of few minutes. (M.D.)

A Comparative Analysis of the Rebound Hammer and Ultrasonic ...

African Journals Online (AJOL)

This work presents a study on the comparison between some non-destructive testing tech-niques (Rebound Hammer and Ultrasonic Pulse Velocity). Tests were performed to com-pare the accuracy between the rebound hammer and the ultrasonic pulse velocity methodin estimating the strength of concrete. Eighty samples ...

Avoiding steam-bubble-collapse-induced water hammers in piping systems

International Nuclear Information System (INIS)

Chou, Y.; Griffith, P.

1989-10-01

In terms of the frequency of occurrence, steam bubble collapse in subcooled water is the dominant initiating mechanism for water hammer events in nuclear power plants. Water hammer due to steam bubble collapse occurs when water slug forms in stratified horizontal flow, or when steam bubble is trapped at the end of the pipe. These types of water hammer events have been studied experimentally and analytically in order to develop stability maps showing those combinations of filling velocities and liquid subcooling that cause water hammer and those which don't. In developing the stability maps, experiments with different piping orientations were performed in a low pressure laboratory apparatus. Details of these experiments are described, including piping arrangement, test procedures, and test results. Visual tests using a transparent Lexan pipe are also performed to study the flow regimes accompanying the water hammer events. All analytical models were tested by comparison with the corresponding experimental results. Based on these models, and step-by-step approach for each flow geometry is presented for plant designers and engineers to follow in avoiding water hammer induced by steam bubble collapse when admitting cold water into pipes filled with steam. 37 refs., 54 figs., 2 tabs

TPS-HAMMER: improving HAMMER registration algorithm by soft correspondence matching and thin-plate splines based deformation interpolation.

Science.gov (United States)

Wu, Guorong; Yap, Pew-Thian; Kim, Minjeong; Shen, Dinggang

2010-02-01

We present an improved MR brain image registration algorithm, called TPS-HAMMER, which is based on the concepts of attribute vectors and hierarchical landmark selection scheme proposed in the highly successful HAMMER registration algorithm. We demonstrate that TPS-HAMMER algorithm yields better registration accuracy, robustness, and speed over HAMMER owing to (1) the employment of soft correspondence matching and (2) the utilization of thin-plate splines (TPS) for sparse-to-dense deformation field generation. These two aspects can be integrated into a unified framework to refine the registration iteratively by alternating between soft correspondence matching and dense deformation field estimation. Compared with HAMMER, TPS-HAMMER affords several advantages: (1) unlike the Gaussian propagation mechanism employed in HAMMER, which can be slow and often leaves unreached blotches in the deformation field, the deformation interpolation in the non-landmark points can be obtained immediately with TPS in our algorithm; (2) the smoothness of deformation field is preserved due to the nice properties of TPS; (3) possible misalignments can be alleviated by allowing the matching of the landmarks with a number of possible candidate points and enforcing more exact matches in the final stages of the registration. Extensive experiments have been conducted, using the original HAMMER as a comparison baseline, to validate the merits of TPS-HAMMER. The results show that TPS-HAMMER yields significant improvement in both accuracy and speed, indicating high applicability for the clinical scenario. Copyright (c) 2009 Elsevier Inc. All rights reserved.

Hydrodynamics of the Fluid Filtrate on Drilling-In

Science.gov (United States)

Abbasov, É. M.; Agaeva, N. A.

2014-01-01

The volume of the liquid penetrating into the formation after drilling-in has been determined on the basis of theoretical investigations. The dynamics of change in the bottom-hole pressure has been determined in this process. It has been shown that because of the water hammer, the bottom-hole pressure can be doubled in the presence of large fractures and pores closer to the well-bottom zone.

Excavation and drilling at a spent-fuel test facility in granitic rock

Energy Technology Data Exchange (ETDEWEB)

Patrick, W.C.; Mayr, M.C.

1981-10-01

Funding for a project to test the feasibility of safe and reliable storage and retrieval of spent fuel from a commercial nuclear reactor was approved by the Department of Energy on June 2, 1978. By May 28, 1980, 11 spent-fuel assemblies had been emplaced 420 m below the surface in the Climax granitic stock at the Nevada Test Site. Design and construction of the Spent Fuel Test-Climax, including fuel emplacement, had taken less than two years, at a total cost of $18.4 million. Construction activities were preceded by geologic exploration using four cored holes and existing underground workings. The sinking of a 0.76-m-diam shaft to the 420-m level initiated construction at the site. Effective rates of sinking varied from 0.16 m/h with a rotary tricone drill to 0.5 m/h with a hammer drill. Underground excavation included a central canister-storage drift 4.6 x 6.1 x 64 m long, two parallel 3.4 x 3.4-m heater drifts, and a tail drift. About 6700 m{sup 3} were excavated at an average rate of 2 m{sup 3}/h, and 178 cored holes, with diameters from 38 to 152 mm, were drilled. A total length of nearly 1100 m was drilled at rates ranging from 0.4 m/h to 1 m/h, depending on hole size and drilling equipment. Eighteen 610-mm-diam canister emplacement holes were hammer-drilled at an average rate of 1.4 m/h. The use of the critical path method, integrated contractors, and close cooperation between project participants facilitated completion of the project on schedule.

Excavation and drilling at a spent-fuel test facility in granitic rock

International Nuclear Information System (INIS)

Patrick, W.C.; Mayr, M.C.

1981-10-01

Funding for a project to test the feasibility of safe and reliable storage and retrieval of spent fuel from a commercial nuclear reactor was approved by the Department of Energy on June 2, 1978. By May 28, 1980, 11 spent-fuel assemblies had been emplaced 420 m below the surface in the Climax granitic stock at the Nevada Test Site. Design and construction of the Spent Fuel Test-Climax, including fuel emplacement, had taken less than two years, at a total cost of $18.4 million. Construction activities were preceded by geologic exploration using four cored holes and existing underground workings. The sinking of a 0.76-m-diam shaft to the 420-m level initiated construction at the site. Effective rates of sinking varied from 0.16 m/h with a rotary tricone drill to 0.5 m/h with a hammer drill. Underground excavation included a central canister-storage drift 4.6 x 6.1 x 64 m long, two parallel 3.4 x 3.4-m heater drifts, and a tail drift. About 6700 m 3 were excavated at an average rate of 2 m 3 /h, and 178 cored holes, with diameters from 38 to 152 mm, were drilled. A total length of nearly 1100 m was drilled at rates ranging from 0.4 m/h to 1 m/h, depending on hole size and drilling equipment. Eighteen 610-mm-diam canister emplacement holes were hammer-drilled at an average rate of 1.4 m/h. The use of the critical path method, integrated contractors, and close cooperation between project participants facilitated completion of the project on schedule

Condensation induced water hammer. Overview and own experiments

International Nuclear Information System (INIS)

Dirndorfer, Stefan; Doerfler, Michael; Kulisch, Helmut; Malcherek, Andreas

2012-01-01

A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this phenomenon and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (orig.)

Condensation-induced water hammer - overview and own experiments

International Nuclear Information System (INIS)

Dirndorfer, S.; Doerfler, M.; Kulisch, H.; Malcherek, A.

2011-01-01

A condensation induced water hammer is a severe effect that has caused damages and even fatalities worldwide. This effect is not limited to the nuclear industry only. Generally it can occur in every pipe that contains water and steam (two-phase-flow). To date many experiments were executed to study this effect and to validate existing water hammer codes. But theoretically versus measured results show a very high degree of deviation. Information about those experiments was obtained by literature review. This information is presented additionally to a test facility, which has been developed in order to generate water hammers. The test device is introduced in this paper and its main functions are briefly explained. In contrast to other experiments, water hammers at the UniBw are performed under controlled conditions. Air in water is a disruptive parameter that causes vigorous deviations between the theoretical system code and the experimental measurements. As in the test device presented in this paper, deionised water without air is used, this effect is ruled out. Furthermore the inception of a water hammer is controlled by a scientist. The experimental results will characterise the dynamic response of the test device as a function of system pressure, filling degree and sub-cooling. (author)

Validation of CATHENA MOD-3.5/Rev0 for single-phase water hammer

International Nuclear Information System (INIS)

Beuthe, T.G.

2000-01-01

This paper describes work performed to validate the system thermalhydraulics code CATHENA MOD-3.5c/Rev0 for single-phase water hammer. Simulations were performed and are compared quantitatively against numerical tests and experimental results from the Seven Sisters Water Hammer Facility to demonstrate CATHENA can predict the creation and propagation of pressure waves when valves are opened and closed. Simulations were also performed to show CATHENA can model the behaviour of reflected and transmitted pressure waves at area changes, dead ends, tanks, boundary conditions, and orifices in simple and more complex piping systems. The CATHENA results are shown to calculate pressure and wave propagation speeds to within 0.2% and 0.5% respectively for numerical tests and within 3.3% and 5% for experimental results respectively. These results are used to help validate CATHENA for use in single-phase water hammer analysis. They also provide assurance that the fundamental parameters needed to successfully model more complex forms of water hammer are accounted for in the MOD-3.5c/Rev0 version of CATHENA, and represent the first step in the process to validate the code for use in modelling two-phase water hammer and condensation-induced water hammer. (author)

Review of two-phase water hammer

International Nuclear Information System (INIS)

Beuthe, T.G.

1997-01-01

In a thermalhydraulic system like a nuclear power plant, where steam and water mix and are used to transport large amounts of energy, there is a potential to create two-phase water hammer. Large water hammer pressure transients are a threat to piping integrity and represent an important safety concern. Such events may cause unscheduled plant down time. The objective of this review is to provide a summary of the information on two-phase water hammer available in the open literature with particular emphasis on water hammer occurrences in nuclear power plants. Past reviews concentrated on studies concerned with preventing water hammer. The present review focuses on the fundamental experimental, analytical, and modelling studies. The papers discussed here were chosen from searches covering up to July 1993. (author)

Water hammers in direct contact heater systems

International Nuclear Information System (INIS)

Uffer, R.

1983-01-01

This paper discusses the causes and mitigation or prevention of water hammers occurring in direct contact heaters and their attached lines. These water hammers are generally caused by rapid pressure reductions in the heaters or by water lines not flowing full. Proper design and operating measures can prevent or mitigate water hammer occurrence. Water hammers often do not originate at the areas where damage is noted

Observations on steam generator water hammer

International Nuclear Information System (INIS)

Hildebrandt, P.C.

1979-01-01

The present state of understanding of water hammer phenomena apparently does not permit analytically predicting the occurrence or consequence of water hammer, with any confidence, or conclusively evaluating the benefit associated with any particular action taken to ameliorate an existing or potential water hammer problem. Features or fixes are incorporated based on overwhelming the problem, and trial and error

Water hammer and cavitational hammer in process plant pipe systems

International Nuclear Information System (INIS)

Dudlik, A.; Schoenfeld, S.B.H.; Hagemann, O.; Fahlenkamp, H.

2003-01-01

Fast acting valves are often applied for quick safety shut-down of pipelines for liquids and gases in the chemical and petrochemical industry as well as in power plants and state water supplies. The fast deceleration of the liquid leads to water hammer upstream the valve and to cavitational hammer downstream the fast closing valve. The valve characteristics given by manufacturers are usually measured at steady state flow conditions of the liquid. In comparison, the dynamic characteristics depend on the initial liquid velocity, valve closing velocity, the absolute pipe pressure and the pipe geometry. Fraunhofer UMSICHT conducts various test series examining valve dynamic characteristics in order of the dynamic analysis of pressure surges in fast closing processes. Therefore a test rig is used which consists of two pipelines of DN 50 and DN 100 with an approximate length of 230 m each. In this paper the results of performed pressure surge experiments with fast closing and opening valves will be compared to calculations of commercial software programs such as MONA, FLOWMASTER 2. Thus the calculation software for water supply, power plants oil and gas and chemical industry can be permanently improved. (orig.)

Paint Scaler. Innovative Technology Summary Report

International Nuclear Information System (INIS)

None

2000-01-01

The Paint Scaler can collect paint samples quickly and efficiently for lab analysis. The Rotary Hammer Drill is a 24-V battery operated, 3/4-in. rotary hammer drill. When used with an optional chipping adapter, the Bosch Rotary Hammer Drill can be used to perform chipping and chiseling tasks such as paint removal from either concrete or metal surfaces. It is ultra-compact, lightweight with an ergonomic balanced grip. The battery operation gives the operator more flexibility during sampling activities

Meshless computation of water hammer

NARCIS (Netherlands)

Tijsseling, A.S.; Bergant, A.

2007-01-01

Water hammer concerns the generation, propagation, reflection and damping of pressure waves in liquidfilled pipe systems. The numerical simulation of water-hammer events is usually based on one-dimensional mathematical models. Two equations representing the conservation of mass and momentum govern

Water hammer in nuclear power plants

International Nuclear Information System (INIS)

1979-07-01

In the past few years, licensees of operating reactors have reported a large number of water hammer events during commercial operation. Most of these events resulted in damage to piping supports and restraints. A few cases involved small cracks or ruptures in feedwater systems. As a result, in 1977 the NRC staff initiated a review of reported water hammer events and of the potential for occurrence of water hammer in all fluid systems that could have an impact on plant safety. The objectives of the review were to identify the causes of water hammer events that could affect reactor safety and to recommend further staff actions needed to reduce the likelihood of such events

21 CFR 890.1450 - Powered reflex hammer.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered reflex hammer. 890.1450 Section 890.1450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... hammer. (a) Identification. A powered reflex hammer is a motorized device intended for medical purposes...

Automated Grid Monitoring for LHCb through HammerCloud

CERN Multimedia

CERN. Geneva

2015-01-01

The HammerCloud system is used by CERN IT to monitor the status of the Worldwide LHC Computing Grid (WLCG). HammerCloud automatically submits jobs to WLCG computing resources, closely replicating the workflow of Grid users (e.g. physicists analyzing data). This allows computation nodes and storage resources to be monitored, software to be tested (somewhat like continuous integration), and new sites to be stress tested with a heavy job load before commissioning. The HammerCloud system has been in use for ATLAS and CMS experiments for about five years. This summer's work involved porting the HammerCloud suite of tools to the LHCb experiment. The HammerCloud software runs functional tests and provides data visualizations. HammerCloud's LHCb variant is written in Python, using the Django web framework and Ganga/DIRAC for job management.

A different challenge: the directional drilled crossing for the Yacuiba - Rio Grande Gas Line Project - GASYRG

Energy Technology Data Exchange (ETDEWEB)

Green, Wayne; Garcia, Francisco [Bolinter Ltda., Santa Cruz (Bolivia); Montano, Ruben [Transierra, Santa Cruz (Bolivia)

2003-07-01

The Rio Grande River's directional drilling, 2002 m. long and 25 m. deep was a great challenge for Transierra - Owner - as well as Laney - Bolinter - Contractor - to accomplish a feat yet to be done in the entire world. The dedication of the people involved showed their degree of professionalism that these companies have obtained and the determination in doing the job overcoming unforeseen obstacles and still being able to finish on time, mitigating environmental impacts and leaving a first class crossing. This document presents a description of the technical, logistic and construction factors that were involved in the project and which allowed to perform 7 directional drillings, including Rio Grande River, which during the pull got the last 60 m. of pipe stuck, being freed only after using a pneumatic hammer. (author)

Uncertainty and sensitivity analysis of parameters affecting water hammer pressure wave behaviour

International Nuclear Information System (INIS)

Kaliatka, A.; Uspuras, E.; Vaisnoras, M.

2006-01-01

Pressure surges occurring in pipeline systems may be caused by fast control interference, start up and shut down processes and operation failure. They lead to water hammer upstream the closing valve and cavitational hammer downstream the valve, which may cause considerable damages to the pipeline and the support structures. Appearance of water hammer in thermal-hydraulic systems was widely studied employing different state-of-the-art thermal-hydraulic codes in many organizations. For the analysis water hammer test performed at Fraunhofer Institute for Environmental, Safety and Energy Technology (UMSICHT) at Oberhausen was considered. This paper presents the comparison of UMSICHT test facility experiment calculations employing the best estimate system code RELAP5/Mod3.3 to measured water hammer values after fast closure of a valve. The analysis revealed that the calculated first pressure peak, which has the highest value, matches the measured value very well. The performed analysis (as well as any other analyses) as a results of each individual calculation always contains uncertainty owing to initial conditions of installations, errors of measuring systems, errors caused by nodalization of objects at modelling, code correlations, etc. In this connection, results of uncertainty and sensitivity analysis of the initial conditions and code-selected models are shown in the paper. (orig.)

Water-hammer prevention, mitigation, and accommodation: a perspective

International Nuclear Information System (INIS)

Kim, J.H.

1987-01-01

The purpose of this paper is to present an industry perspective on water hammer, revisit the issues, and renew interest in this area with aim to prevent, mitigate, and accommodate water hammer. Water hammer keeps recurring in nuclear power plants and damages plant components and impacts on plant operations and availability through forced outages of plants. The implication is that water hammer in nuclear power plants still needs attention and is a problem that has not been fundamentally resolved. The paper displays statistics of the reported water hammer events between 1969 and 1985. The consequences of these water hammer events were: pipe support damage (hangers, anchors, and snubbers), 60%; component damage (piping, pumps, and valves), 17%; reactor trip, 10%; and plant shutdown, 7%. Reactor trips and plant shutdowns account for 17% of the event consequences. At the request of the nuclear utility industry, a workshop on water hammer was sponsored by the Electric Power Research Institute (EPRI), with cosponsorship from Northeast Utility Service Company, Yankee Atomic Electric Company, and Boston Edison Company, which drew some 90 specialists representing 28 utility companies as well as other nuclear industry, academia, and the NRC. The workshop recommendations are summarized

HammerCloud: A Stress Testing System for Distributed Analysis

International Nuclear Information System (INIS)

Ster, Daniel C van der; García, Mario Úbeda; Paladin, Massimo; Elmsheuser, Johannes

2011-01-01

Distributed analysis of LHC data is an I/O-intensive activity which places large demands on the internal network, storage, and local disks at remote computing facilities. Commissioning and maintaining a site to provide an efficient distributed analysis service is therefore a challenge which can be aided by tools to help evaluate a variety of infrastructure designs and configurations. HammerCloud is one such tool; it is a stress testing service which is used by central operations teams, regional coordinators, and local site admins to (a) submit arbitrary number of analysis jobs to a number of sites, (b) maintain at a steady-state a predefined number of jobs running at the sites under test, (c) produce web-based reports summarizing the efficiency and performance of the sites under test, and (d) present a web-interface for historical test results to both evaluate progress and compare sites. HammerCloud was built around the distributed analysis framework Ganga, exploiting its API for grid job management. HammerCloud has been employed by the ATLAS experiment for continuous testing of many sites worldwide, and also during large scale computing challenges such as STEP'09 and UAT'09, where the scale of the tests exceeded 10,000 concurrently running and 1,000,000 total jobs over multi-day periods. In addition, HammerCloud is being adopted by the CMS experiment; the plugin structure of HammerCloud allows the execution of CMS jobs using their official tool (CRAB).

Drilling-induced borehole-wall damage at spent fuel test-climax

International Nuclear Information System (INIS)

Weed, H.C.; Durham, W.B.

1982-12-01

Microcracks in a sample of quartz monzonite from the Spent Fuel Test-Climax were measured by means of a scanning electron microscope in order to estimate the background level of damage near the borehole-wall. It appears that the hammer-drilling operation used to create the borehole has caused some microfracturing in a region 10 to 30 mm wide around the borehole. Beyond 30 mm, the level of microfracturing cannot be distinguished from background

S-HAMMER: hierarchical attribute-guided, symmetric diffeomorphic registration for MR brain images.

Science.gov (United States)

Wu, Guorong; Kim, Minjeong; Wang, Qian; Shen, Dinggang

2014-03-01

Deformable registration has been widely used in neuroscience studies for spatial normalization of brain images onto the standard space. Because of possible large anatomical differences across different individual brains, registration performance could be limited when trying to estimate a single directed deformation pathway, i.e., either from template to subject or from subject to template. Symmetric image registration, however, offers an effective way to simultaneously deform template and subject images toward each other until they meet at the middle point. Although some intensity-based registration algorithms have nicely incorporated this concept of symmetric deformation, the pointwise intensity matching between two images may not necessarily imply the matching of correct anatomical correspondences. Based on HAMMER registration algorithm (Shen and Davatzikos, [2002]: IEEE Trans Med Imaging 21:1421-1439), we integrate the strategies of hierarchical attribute matching and symmetric diffeomorphic deformation to build a new symmetric-diffeomorphic HAMMER registration algorithm, called as S-HAMMER. The performance of S-HAMMER has been extensively compared with 14 state-of-the-art nonrigid registration algorithms evaluated in (Klein et al., [2009]: NeuroImage 46:786-802) by using real brain images in LPBA40, IBSR18, CUMC12, and MGH10 datasets. In addition, the registration performance of S-HAMMER, by comparison with other methods, is also demonstrated on both elderly MR brain images (>70 years old) and the simulated brain images with ground-truth deformation fields. In all experiments, our proposed method achieves the best registration performance over all other registration methods, indicating the high applicability of our method in future neuroscience and clinical applications. Copyright © 2013 Wiley Periodicals, Inc.

Treatment of Rigid Hammer-Toe Deformity: Permanent Versus Removable Implant Selection.

Science.gov (United States)

Doty, Jesse F; Fogleman, Jason A

2018-03-01

Hammer-toe deformities that fail nonoperative treatment can be successfully addressed with proximal interphalangeal joint resection arthroplasty or fusion. The goal of surgery is to eliminate the deformity and rigidly fix the toe in a well-aligned position. Hammer-toe correction procedures can be performed with temporary Kirschner wire (K-wire) fixation for 3 to 6 weeks with high success rates. Pain relief with successful hammer-toe correction approaches 90%; patient satisfaction rates approximate 84%. Although complication rates are rare in most series, there remains a concern regarding exposed temporary K-wire fixation, which has led to the development of multiple permanent internal fixation options. Copyright © 2017 Elsevier Inc. All rights reserved.

Extended Reach Drilling on the example of Reelwell Drilling Method: Influence examination of different drill pipes on drilling performance on Idun field on the Norwegian Continental Shelf by PGNiG Norway AS.

OpenAIRE

Krol, Dariusz Pawel

2011-01-01

Master's thesis in Petroleum engineering Horizontal or extended reach drilling is incredibly fast growing technology. Although in some areas of the world ERD is still novelty, most of oil companies have been using the technology reliably and successfully for dozens of years. And those companies want to improve well-worn solutions to obtain better performance, thereby reducing costs. One of the main aspects that affects drilling performance and efficiency is adequate choice of drill pipe...

Water hammer in USA nuclear power plants and it's evaluation

International Nuclear Information System (INIS)

Liu Shuqian.

1987-01-01

The results of evaluations about the water hammer events in USA nuclear power plants in recent years are summarily reported. The evaluations included underlying causes and frequency of water hammer events, damages incurred and systems affected. Through the evaluations about water hammer events and on the basis of past operation experiences in nuclear power plants, the design and operational modifications to prevent or mitigate water hammer events were presented. The NRC's current opinions relating to the water hammer problems are summarized, the importance of water hammer events for nuclear power plants construction in China is indicated

Improved dental implant drill durability and performance using heat and wear resistant protective coatings.

Science.gov (United States)

Er, Nilay; Alkan, Alper; İlday, Serim; Bengu, Erman

2018-03-02

Dental implant drilling procedure is an essential step for implant surgery and frictional heat appeared in bone during drilling is a key factor affecting the success of an implant. The aim of this study is to increase the dental implant drill lifetime and performance using heat- and wear-resistant protective coatings hence to decrease the alveolar bone temperature caused by the dental implant drilling procedure. Commercially obtained stainless steel drills were coated with titanium aluminum nitride, diamond-like carbon, titanium boron nitride, and boron nitride coatings via magnetron-sputter deposition. Drilling procedure was performed on a bovine femoral cortical bone under the conditions mimicking clinical practice, where the tests were performed both under water-assisted cooling and under the conditions without any cooling was applied. Coated drill performances and durabilities were compared to that of three commonly used commercial drills which surfaces are made from namely; zirconia, black diamond and stainless steel. Protective coatings with boron nitride, titanium boron nitride and diamond-like carbon have significantly improved drill performance and durability. Especially boron nitride-coated drills have performed within safe bone temperature limits for 50 drillings even without any cooling is applied. Titanium aluminium nitride coated drills did not show any improvement over commercially obtained stainless steel drills. Surface modification using heat and wear resistant coatings is an easy and highly effective way to improve implant drill performance and durability, which can reflect positively on surgical procedure and healing period afterwards. The noteworthy success of different types of coatings is novel and likely to be applicable to various other medical systems.

Developmental test report, assessment of XT-70E percussion drill rig operation in tank farms

International Nuclear Information System (INIS)

Dougherty, L.F.

1996-01-01

The following report documents the testing of the XT-70E percussion drill rig for use in the 241-SX Tank Farm. The test is necessary to support evaluation of the safety and authorization level of the proposed activity of installing up to three new drywells in the 241- SX Tank Farm. The proposed activity plans to install drywells by percussion drilling 7 inch O.D./6 inch I.D. pipe in close proximity of underground storage tanks and associated equipment. The load transmitted from the drill rig's percussion hammer through the ground to the tank structure and equipment is not known and therefore testing is required to ensure the activity is safe and authorized

Water Hammer in Pumped Sewer Mains

DEFF Research Database (Denmark)

Larsen, Torben

This publication is intended for engineers seeking an introduction to the problem of water hammer in pumped pressure mains. This is a subject of increasing interest because of the development of larger and more integrated sewer systems. Consideration of water hammer is essential for structural...

Reduced-impact sliding pressure control valve for pneumatic hammer drill

Science.gov (United States)

Polsky, Yarom [Oak Ridge, TN; Grubelich, Mark C [Albuquerque, NM; Vaughn, Mark R [Albuquerque, NM

2012-05-15

A method and means of minimizing the effect of elastic valve recoil in impact applications, such as percussive drilling, where sliding spool valves used inside the percussive device are subject to poor positioning control due to elastic recoil effects experienced when the valve impacts a stroke limiting surface. The improved valve design reduces the reflected velocity of the valve by using either an energy damping material, or a valve assembly with internal damping built-in, to dissipate the compression stress wave produced during impact.

Correlation of the manual compaction hammer with mechanical hammers for the Marshall method of design for asphaltic concrete.

Science.gov (United States)

1964-09-01

The purpose of this investigation was to establish, through a series of correlations, the compactive effort (number of blows) needed using the mechanical hammers to yield similar physical properties obtained with 75 blows of the manual hammer.

Experiments of condensation-induced water hammers at the UniBw Munich

International Nuclear Information System (INIS)

Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas

2013-01-01

Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

Experiments of condensation-induced water hammers at the UniBw Munich

Energy Technology Data Exchange (ETDEWEB)

Dirndorfer, Stefan; Kulisch, Helmut; Malcherek, Andreas [Universitaet der Bundeswehr Muenchen, Neubiberg (Germany). Hydromechanik und Wasserbau

2013-03-15

Condensation-induced water hammers belong to the most serious and complex pressure surges. Experimental data from literature are scanty, incomplete, not public or simply missing. A new test facility at the UniBw (University of the German Armed Forces) was constructed to perform own experiments within a research alliance. This new test facility uses a complete new approach. In contrast to other test stations, the UniBw water hammer test facility is a closed system. This leads on the one hand to a more complex handling with respect of conducting experiments but on the other hand also to a more realistic characterization of thermo-hydraulic phenomena which can occur in a power plant. The first results of a measured condensation-induced water hammer are presented. (orig.)

Investigation of water hammer in Globochica HPP

International Nuclear Information System (INIS)

Bergant, Anton; Saveski, Vasil; Sijamhodjic, Esad

2004-01-01

Water hammer should be one of the key elements of the feasibility and design studies in order to ensure safe operation of the hydroelectric power plant (HPP). The main objective of this paper is to identify critical flow regimes which may cause unacceptable water hammer in a Francis turbine HPP. Water hammer is described by the set of hyperbolic partial differential equations, the continuity equation and the equation of motion. The method of characteristics is used for solving these equations. The water turbine is treated as a boundary condition within the method of characteristics. The paper concludes with water hammer analysis in Globocica HPP, Republic of Macedonia. The system tinder consideration is fitted with two 23 MW Francis turbines. There is a reasonable agreement between the computational is field test results. (Author)

An evaluation of water hammer in nuclear power plants

International Nuclear Information System (INIS)

Serkiz, A.

1983-01-01

Water hammer can occur as a result of to steam-void collapse, steam-driven slugs of water, pump startup into voided lines, and inadverdent closures of valves; the result is large hydraulic pressure loads. Since 1968, about 150 water hammer events have been reported in U.S. nuclear power plants; damage has been confined to pipe hangers and snubbers. The increase in reported water hammer events in the 1970s led to the designation of water hammer as Unresolved Safety Issue A-1 in 1979. Since the mid-1970s reported occurrences and their underlying phenomena have been studied, and corrective design and operational measures have been implemented. This paper presents the results of generic evaluations of water hammer occurrence and reported damage and sets forth technical findings. These findings indicate that good design practices and operational procedures can minimize the occurrence of water hammer

Advanced Drilling through Diagnostics-White-Drilling

International Nuclear Information System (INIS)

FINGER, JOHN T.; GLOWKA, DAVID ANTHONY; LIVESAY, BILLY JOE; MANSURE, ARTHUR J.; PRAIRIE, MICHAEL R.

1999-01-01

A high-speed data link that would provide dramatically faster communication from downhole instruments to the surface and back again has the potential to revolutionize deep drilling for geothermal resources through Diagnostics-While-Drilling (DWD). Many aspects of the drilling process would significantly improve if downhole and surface data were acquired and processed in real-time at the surface, and used to guide the drilling operation. Such a closed-loop, driller-in-the-loop DWD system, would complete the loop between information and control, and greatly improve the performance of drilling systems. The main focus of this program is to demonstrate the value of real-time data for improving drilling. While high-rate transfer of down-hole data to the surface has been accomplished before, insufficient emphasis has been placed on utilization of the data to tune the drilling process to demonstrate the true merit of the concept. Consequently, there has been a lack of incentive on the part of industry to develop a simple, low-cost, effective high-speed data link. Demonstration of the benefits of DWD based on a high-speed data link will convince the drilling industry and stimulate the flow of private resources into the development of an economical high-speed data link for geothermal drilling applications. Such a downhole communication system would then make possible the development of surface data acquisition and expert systems that would greatly enhance drilling operations. Further, it would foster the development of downhole equipment that could be controlled from the surface to improve hole trajectory and drilling performance. Real-time data that would benefit drilling performance include: bit accelerations for use in controlling bit bounce and improving rock penetration rates and bit life; downhole fluid pressures for use in the management of drilling hydraulics and improved diagnosis of lost circulation and gas kicks; hole trajectory for use in reducing directional

Skalak's extended theory of water hammer

NARCIS (Netherlands)

Tijsseling, A.S.; Lambert, M.F.; Simpson, A.R.; Stephens, M.L.; Vítkovský, J.P.; Bergant, A.

2008-01-01

Half a century ago Richard Skalak [see T.C. Skalak, A dedication in memoriam of Dr. Richard Skalak, Annual Review of Biomedical Engineering 1 (1999) 1–18] published a paper with the title "An extension of the theory of water hammer" [R. Skalak, An Extension of the Theory of Water Hammer, PhD Thesis,

Hypothenar hammer syndrome.

Science.gov (United States)

Schröttle, Angelika; Czihal, Michael; Lottspeich, Christian; Kuhlencordt, Peter; Nowak, Dennis; Hoffmann, Ulrich

2015-05-01

The diagnosis of hypothenar hammer syndrome (HHS) should be considered in the case of hand ischemia in people who occupationally or recreationally use the hypothenar region literally as a “hammer”. Routine diagnostics should consist of physical examination including Allen’s test, acral plethysmography and duplex sonography. According to the prevailing opinion angiography remains the «gold standard test» for establishing the diagnosis of HHS. Early diagnosis allows more effective therapeutic strategies and is important to prevent long-term negative medical sequelae. Several basic principles apply to all patients, for example hand protection and smoking cessation. The optimal treatment options, particularly the indication for surgery, remain controversial due to a lack of sound data from case series or prospective randomized trials.

Water hammer and its effect on ageing: an analytical study

International Nuclear Information System (INIS)

Kedia, Suruchi

2006-01-01

Water hammer can be disastrous from the point of view of ageing of the pipe(s)/Piping system. Design of restraints and protection devices for the various piping systems must consider severe stresses that may generate because of fluid transients. These fluid transients are termed as water hammer when it is restricted to water. But to have limited margins on the stress loads of piping system it is very important to predict the actual dimensions of the stresses. This paper covers various causes and analyses of the situations under which water hammer waves get generated and also way(s) to have control on occurrences of such situations. Few case studies are also covered showing the results and graphs of the stress waves generated because of water hammer. Effort has also been made in the paper in the direction to find out the methodology to compute the ageing of the system because of water hammer waves. Further in this paper an attempt is made to show the systematic methodology towards the diagnosis of water hammer that can be treated as a foundation stone for the creation of water hammer diagnosis system. Active measures to minimize the water hammer intensity by influencing fluid dynamic conditions of the system will also be suggested. Finally the paper will present the ageing aspects because of the stresses that generate due to water hammer. (author)

Simulation of low pressure water hammer

Science.gov (United States)

Himr, D.; Habán, V.

2010-08-01

Numerical solution of water hammer is presented in this paper. The contribution is focused on water hammer in the area of low pressure, which is completely different than high pressure case. Little volume of air and influence of the pipe are assumed in water, which cause sound speed change due to pressure alterations. Computation is compared with experimental measurement.

Automated Grid Monitoring for the LHCb Experiment Through HammerCloud

CERN Document Server

Dice, Bradley

2015-01-01

The HammerCloud system is used by CERN IT to monitor the status of the Worldwide LHC Computing Grid (WLCG). HammerCloud automatically submits jobs to WLCG computing resources, closely replicating the workflow of Grid users (e.g. physicists analyzing data). This allows computation nodes and storage resources to be monitored, software to be tested (somewhat like continuous integration), and new sites to be stress tested with a heavy job load before commissioning. The HammerCloud system has been in use for ATLAS and CMS experiments for about five years. This summer's work involved porting the HammerCloud suite of tools to the LHCb experiment. The HammerCloud software runs functional tests and provides data visualizations. HammerCloud's LHCb variant is written in Python, using the Django web framework and Ganga/DIRAC for job management.

Hammer's Monsters: A Screen Bestiary

OpenAIRE

Jones, Matthew; Chibnall, S.

2016-01-01

This public exhibition, housed in the DMU Heritage Centre, ran from October 2016 to October 2017. It displayed materials from the Hammer Script Archive held by the Cinema and Television History (CATH) Research Centre at DMU and provided a critical and historical commentary on these materials. Locating the archival objects and images within the industrial and creative history of the iconic Hammer Film Productions, the exhibition invited the public to reflect on the place of this studio within ...

Analysis of water hammer events in nuclear power plants

International Nuclear Information System (INIS)

Sato, Masahiro; Yanagi, Chihiro

1999-01-01

A water hammer issue in nuclear power plants was one of unresolved safety issues listed by the United States Nuclear Regulatory Commission and was regarded as resolved. But later on, the water hammer events are still experienced intermittently, while the number of the events is decreasing. We collected water hammer events of PWRs in Japan and the United States and relevant documents, analyzed them, and studied corrective actions taken by Japanese plants. As a result, it is confirmed that preventive measured in design, operation etc. have been already taken and that mitigation mechanisms against water hammer have also been considered. However, it is clarified that attention should be continuously paid to operation of valves and/or pumps, as the prevention of water hammer still relies on operation. (author)

Analytical models for lower and upper bounds of the condensation-induced water hammer in long horizontal pipes

International Nuclear Information System (INIS)

Chun, Moon Hyun; Park, Joo Wan; Nam, Ho Yun

1992-01-01

Improved analytical models have been proposed that can predict the lower and upper limits of the water hammer region for given flow conditions by incorporation of recent advances made in the understanding of phenomena associated with the condensation-induced water hammer into existing methods. Present models are applicable for steam-water counterflow in a long horizontal pipe geometry. Both lower and upper bounds of the water hammer region are expressed in terms of the 'critical inlet water flow rate' as a function of axial position. Water hammer region boundaries predicted by present and typical existing models are compared for particular flow conditions of the water hammer event occurred at San Onofre Unit 1 to assess the applicability of the models examined. The result shows that present models for lower and upper bounds of the water hammer region compare favorably with the best performing existing models

Treatise on water hammer in hydropower standards and guidelines

International Nuclear Information System (INIS)

Bergant, A; Mazij, J; Karney, B; Pejović, S

2014-01-01

This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants

Treatise on water hammer in hydropower standards and guidelines

Science.gov (United States)

Bergant, A.; Karney, B.; Pejović, S.; Mazij, J.

2014-03-01

This paper reviews critical water hammer parameters as they are presented in official hydropower standards and guidelines. A particular emphasize is given to a number of IEC standards and guidelines that are used worldwide. The paper critically assesses water hammer control strategies including operational scenarios (closing and opening laws), surge control devices (surge tank, pressure regulating valve, flywheel, etc.), redesign of the water conveyance system components (tunnel, penstock), or limitation of operating conditions (limited operating range) that are variably covered in standards and guidelines. Little information is given on industrial water hammer models and solutions elsewhere. These are briefly introduced and discussed in the light of capability (simple versus complex systems), availability of expertise (in house and/or commercial) and uncertainty. The paper concludes with an interesting water hammer case study referencing the rules and recommendations from existing hydropower standards and guidelines in a view of effective water hammer control. Recommendations are given for further work on development of a special guideline on water hammer (hydraulic transients) in hydropower plants.

Estimation on separation efficiency of aluminum from base-cap of spent fluorescent lamp in hammer crusher unit.

Science.gov (United States)

Rhee, Seung-Whee

2017-09-01

In order to separate aluminum from the base-cap of spent fluorescent lamp (SFL), the separation efficiency of hammer crusher unit is estimated by introducing a binary separation theory. The base-cap of SFL is composed by glass fragment, binder, ferrous metal, copper and aluminum. The hammer crusher unit to recover aluminum from the base-cap consists of 3stages of hammer crusher, magnetic separator and vibrating screen. The optimal conditions of rotating speed and operating time in the hammer crusher unit are decided at each stage. At the optimal conditions, the aluminum yield and the separation efficiency of hammer crusher unit are estimated by applying a sequential binary separation theory at each stage. And the separation efficiency between hammer crusher unit and roll crush system is compared to show the performance of aluminum recovery from the base-cap of SFL. Since the separation efficiency can be increased to 99% at stage 3, from the experimental results, it is found that aluminum from the base-cap can be sufficiently recovered by the hammer crusher unit. Copyright © 2017. Published by Elsevier Ltd.

Metal Forming With a Magnetomotive Hammer

Science.gov (United States)

2004-01-01

During the Apollo era Marshall Space Flight Center's engineers developed the Magnetomotive Hammer to remove distortions from Saturn V bulkhead gore segments. Using an intense magnetic field, the Hammer removed manufacturing distortions from rejected segments which otherwise would have been discarded at a cost of $30,000 each. Various automobile, ship and aircraft manufacturers adoped the technology for commercial use.

Effect of hammer mass on upper extremity joint moments.

Science.gov (United States)

Balendra, Nilanthy; Langenderfer, Joseph E

2017-04-01

This study used an OpenSim inverse-dynamics musculoskeletal model scaled to subject-specific anthropometrics to calculate three-dimensional intersegmental moments at the shoulder, elbow and wrist while 10 subjects used 1 and 2 lb hammers to drive nails. Motion data were collected via an optoelectronic system and the interaction of the hammer with nails was recorded with a force plate. The larger hammer caused substantial increases (50-150%) in moments, although increases differed by joint, anatomical component, and significance of the effect. Moment increases were greater in cocking and strike/follow-through phases as opposed to swinging and may indicate greater potential for injury. Compared to shoulder, absolute increases in peak moments were smaller for elbow and wrist, but there was a trend toward larger relative increases for distal joints. Shoulder rotation, elbow varus-valgus and pronation-supination, and wrist radial-ulnar deviation and rotation demonstrated large relative moment increases. Trial and phase durations were greater for the larger hammer. Changes in moments and timing indicate greater loads on musculoskeletal tissues for an extended period with the larger hammer. Additionally, greater variability in timing with the larger hammer, particularly for cocking phase, suggests differences in control of the motion. Increased relative moments for distal joints may be particularly important for understanding disorders of the elbow and wrist associated with hammer use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characteristics of laminar MHD fluid hammer in pipe

International Nuclear Information System (INIS)

Huang, Z.Y.; Liu, Y.J.

2016-01-01

As gradually wide applications of MHD fluid, transportation as well as control with pumps and valves is unavoidable, which induces MHD fluid hammer. The paper attempts to combine MHD effect and fluid hammer effect and to investigate the characteristics of laminar MHD fluid hammer. A non-dimensional fluid hammer model, based on Navier–Stocks equations, coupling with Lorentz force is numerically solved in a reservoir–pipe–valve system with uniform external magnetic field. The MHD effect is represented by the interaction number which associates with the conductivity of the MHD fluid as well as the external magnetic field and can be interpreted as the ratio of Lorentz force to Joukowsky force. The transient numerical results of pressure head, average velocity, wall shear stress, velocity profiles and shear stress profiles are provided. The additional MHD effect hinders fluid motion, weakens wave front and homogenizes velocity profiles, contributing to obvious attenuation of oscillation, strengthened line packing and weakened Richardson annular effect. Studying the characteristics of MHD laminar fluid hammer theoretically supplements the gap of knowledge of rapid-transient MHD flow and technically provides beneficial information for MHD pipeline system designers to better devise MHD systems. - Highlights: • Characteristics of laminar MHD fluid hammer are discussed by simulation. • MHD effect has significant influence on attenuation of wave. • MHD effect strengthens line packing. • MHD effect inhibits Richardson annular effect.

Optimization analysis of swing check valve closing induced water hammer

International Nuclear Information System (INIS)

Han Wenwei; Han Weishi; Guo Qing; Wang Xin; Liu Chunyu

2014-01-01

A mathematical-physics model of double pump parallel feed system was constructed. The water hammer was precisely calculated, which was formed in the closing process of swing check valve. And a systematic analysis was carried out to determine the influence of the torques from both valve plate and damping torsion spring on the valve closing induced water hammer. The results show that the swing check valve would distinctly produce the water hammer during the closing procedure in the double pump parallel feed water system. The torques of the valve plate can partly reduce the water hammer effect, and implying appropriate materials of valve plate and appropriate spring can effectively relieve the harm of water hammer. (authors)

WATER HAMMER OSCILLATIONS IN THE IRRIGATION FACILITIES

Science.gov (United States)

Kurata, Kouichi; Sasaki, Katsuhito; Makihata, Toshiaki

In case a gate installed at the end of discharge conduit is vibrating during discharge, or an air valve is vibrating during water-filling operation into the conduit pipe between main gate and auxiliary gate, and vibration period tv is larger than tc (water hammer propagation time) that is equivalent to the phenomenon of slow closure, there is a possibility that water hammer oscillation in the discharge conduit could be induced. In this paper, by using two case examples, vibration phenomena transmitted to each part are analyzed, on the basis of water pressure fluctuation and pressure wave propagation due to occurrence of water hammer oscillation.

Value-impact analysis for USI A-1, water hammer

International Nuclear Information System (INIS)

Serkiz, A.W.

1983-05-01

The Unresolved Safety Issue (USI) A-1 deals with safety concerns related to water hammer occurrence in nucler power plants. The staff's concerns were prompted by the increasing frequency of water hammer occurrence in the mid-1970's as new plants were coming on line, and in particular, by the feedwater line rupture at Indian Point No. 2 in 1973 (attributed to water hammer induced by steam-void collapse). Principal concerns were: the potential for inadequate dynamic load design, disablement of safety systems, and the release of radioactivity. The staff's views were set forth in NUREG-0582 and water hammer was designated a USI in 1979

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

Science.gov (United States)

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

2016-02-01

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

Study of effect of in-line hydropneumatic accumulators on output characteristics of hydraulic hammer

Science.gov (United States)

Redelin, R. A.; Kravchenko, V. A.; Kamanin, Y. N.; Panichkin, A. V.; Bozhanov, A. A.

2017-10-01

The article presents the results of studies of the effect of in-line hydropneumatic accumulators on the output parameters of a hydraulic hammer during their joint operation. Based on mathematical modeling, computational experiments were performed and the output characteristics of the hammer, depending on the design and operating parameters of the in-line hydropneumatic accumulators, were obtained. It was established that for the most effective operation of the hammer, the precharge pressure of the pressure line hydropneumatic accumulator should be 70-80% of the working pressure of the hydraulic system. The utilization of a hydropneumatic accumulator without special additional devices in the discharge line is impractical.

Water Hammer Analysis using RELAP5/MOD 3.3 for Yonggwang Nuclear Power Unit 1 and 2 Blowdown System

International Nuclear Information System (INIS)

Lee, Sang Il; Kim, Hea Zoo; Chu, Jung Ho; Ahn, Se Hong; Jung, Chang Ho

2010-01-01

Water hammer can be defined as a rapid pressure step occurring in the liquid in a closed pipe caused by a sudden change in the liquid velocity. This pressure acts for a period which is twice the transit time of sonic wave in the pipe. Generally, water hammer can occur in any thermal-hydraulic systems like nuclear power plant and is extremely dangerous for nuclear power plant piping system since, if the pressure induced exceeds the pressure range of the pipe given by the manufacturer, it can lead to the failure of the piping system integrity. For Yonggwang nuclear power unit 1 and 2, water hammer occurred repeatedly on the outlet piping of regenerative heat exchanger of steam generator blowdown system. Thus, design modification was performed to prevent the water hammer and the analysis of effect on water hammer before and after design modification was performed to verify the validity of the design modification

Two-phase water hammer in nuclear power plants

International Nuclear Information System (INIS)

Kim, J.H.

1987-01-01

Water hammer events keep recurring in nuclear power plants. In the mid-1970s, water hammer was designated to be an unresolved safety issue (USI A-1) due to its high frequency of occurrence and the severity of the attendant damages. Between 1969 and 1981, a significant number of water hammer incidents (more than 12 events per year) involving BWRs and PWRs have been reported and evaluated. After intensive evaluations of the events, in late 1983, the U.S. Nuclear Regulatory Commission staff concluded that water hammer was not a serious contributor to the degradation of plant safety and it has been taken off the list of the unresolved safety issues. The frequency decreased to around 11 events per year between 1981 and 1985. Nevertheless, 11 events per year are still unacceptable high, especially in light of the financial losses caused by most events. Some events are not required to be reported. The number of the unreported events are estimated to be five to ten times as many as the reported events. The implication is that water hammer in nuclear power plants still needs attention and is a problem that has not been fundamentally resolved

Pump-stopping water hammer simulation based on RELAP5

International Nuclear Information System (INIS)

Yi, W S; Jiang, J; Li, D D; Lan, G; Zhao, Z

2013-01-01

RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case

Pump-stopping water hammer simulation based on RELAP5

Science.gov (United States)

Yi, W. S.; Jiang, J.; Li, D. D.; Lan, G.; Zhao, Z.

2013-12-01

RELAP5 was originally designed to analyze complex thermal-hydraulic interactions that occur during either postulated large or small loss-of-coolant accidents in PWRs. However, as development continued, the code was expanded to include many of the transient scenarios that might occur in thermal-hydraulic systems. The fast deceleration of the liquid results in high pressure surges, thus the kinetic energy is transformed into the potential energy, which leads to the temporary pressure increase. This phenomenon is called water hammer. Generally water hammer can occur in any thermal-hydraulic systems and it is extremely dangerous for the system when the pressure surges become considerably high. If this happens and when the pressure exceeds the critical pressure that the pipe or the fittings along the pipeline can burden, it will result in the failure of the whole pipeline integrity. The purpose of this article is to introduce the RELAP5 to the simulation and analysis of water hammer situations. Based on the knowledge of the RELAP5 code manuals and some relative documents, the authors utilize RELAP5 to set up an example of water-supply system via an impeller pump to simulate the phenomena of the pump-stopping water hammer. By the simulation of the sample case and the subsequent analysis of the results that the code has provided, we can have a better understand of the knowledge of water hammer as well as the quality of the RELAP5 code when it's used in the water-hammer fields. In the meantime, By comparing the results of the RELAP5 based model with that of other fluid-transient analysis software say, PIPENET. The authors make some conclusions about the peculiarity of RELAP5 when transplanted into water-hammer research and offer several modelling tips when use the code to simulate a water-hammer related case.

Hypothenar hammer syndrome: long-term follow-up after ulnar artery reconstruction with the lateral circumflex femoral artery.

Science.gov (United States)

de Niet, A; Van Uchelen, J H

2017-06-01

In symptomatic patients with hypothenar hammer syndrome, the occluded part of the ulnar artery can be reconstructed with an autologous graft. Venous grafts are used frequently, but they are known for their low patency rate. Arterial grafts show better patency rates than venous grafts in coronary bypass surgery. We performed 11 ulnar artery reconstructions with the descending branch of the lateral circumflex femoral artery and compared these with previously performed venous reconstructions. All patients with an arterial graft reconstruction had a patent graft at a mean follow-up of 63 months. In addition, nine out of 11 patients reported improvement in their symptoms. The patency rate of venous reconstructions in hypothenar hammer syndrome is significantly lower. Arterial grafting for hypothenar hammer syndrome has superior patency compared with venous grafting; we recommend it as the surgical treatment of choice for symptomatic hypothenar hammer syndrome. 4.

Condensation induced water hammer in steam supply system

International Nuclear Information System (INIS)

Andrews, P.B.; Antaki, G.A.; Rawls, G.B.; Gutierrez, B.J.

1995-01-01

The accidental mixing of steam and water usually leads to condensation induced water hammer. This phenomenon is not uncommon in the power and process industries, and is of particular concern due to the high energies which accompany steam transients. The paper discusses the conditions which lead to a recent condensation induced water hammer in a 150 psig steam supply header. The ensuing structural damage, inspection and repairs are described. Finally, a list of design, maintenance and operational cautions are presented to help minimize the potential for condensation induced water hammer in steam lines

Condensation induced water hammer in steam supply system

International Nuclear Information System (INIS)

Andrews, P.B.; Antaki, G.A.; Rawls, G.B.; Gutierrez, B.J.

1995-01-01

The accidental mixing of steam and water usually leads to condensation induced water hammer. THis phenomenon is not uncommon in the power and process industries, and is of particular concern due to the high energies which accompany steam transients. The paper discusses the conditions which lead to a recent condensation induced water hammer in a 150 psig steam supply header. The insuing structural damage, inspection and repairs are described. Finally, a list of design cautions are presented to help minimize the potential for condensation induced water hammer in steam lines

Electromagnetic hammer removes weld distortions from aluminum tanks

Science.gov (United States)

Schwinghamer, R. J.

1965-01-01

Distortions around weld areas on sheet-aluminum tanks and other structures are removed with a portable electromagnetic hammer. The hammer incorporates a coil that generates a controlled high-energy pulsed magnetic field over localized areas on the metal surface.

Dynamic Brazilian Test of Rock Under Intermediate Strain Rate: Pendulum Hammer-Driven SHPB Test and Numerical Simulation

Science.gov (United States)

Zhu, W. C.; Niu, L. L.; Li, S. H.; Xu, Z. H.

2015-09-01

The tensile strength of rock subjected to dynamic loading constitutes many engineering applications such as rock drilling and blasting. The dynamic Brazilian test of rock specimens was conducted with the split Hopkinson pressure bar (SHPB) driven by pendulum hammer, in order to determine the indirect tensile strength of rock under an intermediate strain rate ranging from 5.2 to 12.9 s-1, which is achieved when the incident bar is impacted by pendulum hammer with different velocities. The incident wave excited by pendulum hammer is triangular in shape, featuring a long rising time, and it is considered to be helpful for achieving a constant strain rate in the rock specimen. The dynamic indirect tensile strength of rock increases with strain rate. Then, the numerical simulator RFPA-Dynamics, a well-recognized software for simulating the rock failure under dynamic loading, is validated by reproducing the Brazilian test of rock when the incident stress wave retrieved at the incident bar is input as the boundary condition, and then it is employed to study the Brazilian test of rock under the higher strain rate. Based on the numerical simulation, the strain-rate dependency of tensile strength and failure pattern of the Brazilian disc specimen under the intermediate strain rate are numerically simulated, and the associated failure mechanism is clarified. It is deemed that the material heterogeneity should be a reason for the strain-rate dependency of rock.

Definitions of hammer toe and claw toe: an evaluation of the literature.

Science.gov (United States)

Schrier, Joost C M; Verheyen, Cees C P M; Louwerens, Jan Willem

2009-01-01

Lesser toe surgery is among the most conducted interventions in general orthopedic practice. However, the definitions of hammer toe and claw toe are not uniform. The objective of this literature study is to propose clear definitions for these deformities to establish unambiguous communication. A literature search was performed in the PubMed database (May 2006). Of 81 eligible articles, 42 that stated a clear definition of hammer toe or claw toe were selected. In all 35 articles in which hammer toe was clearly defined, flexion in the proximal interphalangeal joint was part of the definition. Seventeen articles (49%) defined hammer toe as a combination of metatarsophalangeal extension and proximal interphalangeal flexion. Thirteen articles showed flexion of the proximal interphalangeal joint as the single criterion. Twenty-three articles with a clear definition of claw toe were selected. Twenty-one articles (91%) showed metatarsophalangeal extension as part of the claw toe deformity. Twelve articles (52%) regarded metatarsophalangeal extension and flexion of the proximal interphalangeal and distal interphalangeal joints as the essential characteristics. Seven articles described a claw toe as metatarsophalangeal extension with flexion in the proximal interphalangeal joint. There are variations in the definitions of lesser toe deformities in the literature. We propose that extension of the metatarsophalangeal joint is the discriminating factor and essential characteristic for claw toe. Claw toe and hammer toe should be characterized by flexion in the proximal interphalangeal joint, which is the single criterion for a hammer toe. The flexibility of these joints could be a basic factor in discriminating between these deformities. The development of these deformities should be regarded as a continuum in the same pathophysiologic process.

Computerized Hammer Sounding Interpretation for Concrete Assessment with Online Machine Learning.

Science.gov (United States)

Ye, Jiaxing; Kobayashi, Takumi; Iwata, Masaya; Tsuda, Hiroshi; Murakawa, Masahiro

2018-03-09

Developing efficient Artificial Intelligence (AI)-enabled systems to substitute the human role in non-destructive testing is an emerging topic of considerable interest. In this study, we propose a novel hammering response analysis system using online machine learning, which aims at achieving near-human performance in assessment of concrete structures. Current computerized hammer sounding systems commonly employ lab-scale data to validate the models. In practice, however, the response signal patterns can be far more complicated due to varying geometric shapes and materials of structures. To deal with a large variety of unseen data, we propose a sequential treatment for response characterization. More specifically, the proposed system can adaptively update itself to approach human performance in hammering sounding data interpretation. To this end, a two-stage framework has been introduced, including feature extraction and the model updating scheme. Various state-of-the-art online learning algorithms have been reviewed and evaluated for the task. To conduct experimental validation, we collected 10,940 response instances from multiple inspection sites; each sample was annotated by human experts with healthy/defective condition labels. The results demonstrated that the proposed scheme achieved favorable assessment accuracy with high efficiency and low computation load.

Vibration and recoil control of pneumatic hammers. [by air flow pressure regulation

Science.gov (United States)

Constantinescu, I. N.; Darabont, A. V.

1974-01-01

Vibration sources are described for pneumatic hammers used in the mining industry (pick hammers), in boiler shops (riveting hammers), etc., bringing to light the fact that the principal vibration source is the variation in air pressure inside the cylinder. The present state of the art of vibration control of pneumatic hammers as it is practiced abroad, and the solutions adopted for this purpose, are discussed. A new type of pneumatic hammer with a low noise and vibration level is presented.

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

Energy Technology Data Exchange (ETDEWEB)

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)

2012-07-01

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

Preventive measures of water hammer in the design stage of mine drainage system

International Nuclear Information System (INIS)

Wu Dongyan

2012-01-01

The mechanisms and types of water hammer accident in mine drainage system are introduced. Through calculating water hammer pressure head of pump-failure water hammer, the extent of the harm caused by water hammer can be displayed visually, therefore,the preventive measures to be taken in the design stage are put forward in order to reduce water hammer accident. (author)

Adaptation of HAMMER computer code to CYBER 170/750 computer

International Nuclear Information System (INIS)

Pinheiro, A.M.B.S.; Nair, R.P.K.

1982-01-01

The adaptation of HAMMER computer code to CYBER 170/750 computer is presented. The HAMMER code calculates cell parameters by multigroup transport theory and reactor parameters by few group diffusion theory. The auxiliary programs, the carried out modifications and the use of HAMMER system adapted to CYBER 170/750 computer are described. (M.C.K.) [pt

Drill and Blast Performance Evaluation at the Obra Pit of Chirano ...

African Journals Online (AJOL)

Michael

2016-12-02

Dec 2, 2016 ... The methods employed included: drilling performance analysis using statistical methods; ... parameters and blasting practices were acceptable to produce good fragmentation but the actual drilling ..... the explosives was measured from the bottom of ..... Economic and Financial Evaluation, Environmental.

Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

Energy Technology Data Exchange (ETDEWEB)

Dirndorfer, Stefan

2017-01-17

Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

Steam condensation induced water hammer in a vertical up-fill configuration within an integral test facility. Experiments and computational simulations

International Nuclear Information System (INIS)

Dirndorfer, Stefan

2017-01-01

Condensation induced water hammer is a source of danger and unpredictable loads in pipe systems. Studies concerning condensation induced water hammer were predominantly made for horizontal pipes, studies concerning vertical pipe geometries are quite rare. This work presents a new integral test facility and an analysis of condensation induced water hammer in a vertical up-fill configuration. Thanks to the state of the art technology, the phenomenology of vertical condensation induced water hammer can be analysed by means of sufficient high-sampled experimental data. The system code ATHLET is used to simulate UniBw condensation induced water hammer experiments. A newly developed and implemented direct contact condensation model enables ATHLET to calculate condensation induced water hammer. Selected experiments are validated by the modified ATHLET system code. A sensitivity analysis in ATHLET, together with the experimental data, allows to assess the performance of ATHLET to compute condensation induced water hammer in a vertical up-fill configuration.

Simulating water hammer with corrective smoothed particle method

NARCIS (Netherlands)

Hou, Q.; Kruisbrink, A.C.H.; Tijsseling, A.S.; Keramat, A.

2012-01-01

The corrective smoothed particle method (CSPM) is used to simulate water hammer. The spatial derivatives in the water-hammer equations are approximated by a corrective kernel estimate. For the temporal derivatives, the Euler-forward time integration algorithm is employed. The CSPM results are in

Experimental investigation of the piano hammer-string interaction.

Science.gov (United States)

Birkett, Stephen

2013-04-01

Experimental techniques for investigating the piano hammer-string interaction are described. It is argued that the accuracy, consistency, and scope of conclusions of previous studies can be compromised by limitations of the conventional methods relating to key inputs; physical distortion; numerical distortion, particularly when differentiation or integration of measured signals is used to derive primary response variables; contact identification; and synchronization issues. These problems are discussed, and experimental methods that have been devised to avoid them are described and illustrated by detailed results from a study of the hammer-string interaction in a vertical piano. High resolution displacements are obtained directly by non-contact high-speed imaging and quantitative motion tracking. The attention focused on achieving very accurate and consistent temporal and spatial alignment, including the objective procedure used for contact identification, allows meaningful comparisons of responses from separate tests. String motion at the strike point and on each side of it, as well as hammer motion, is obtained for eight dynamic levels from 1.06 to 2.98 m/s impact velocity. Detailed observations of the force-compression behavior of the hammer interacting with real strings are presented. The direct effects of hammer shank deflection and agraffe string pulses on the interaction are also highlighted.

Reconstruction of piano hammer force from string velocity.

Science.gov (United States)

Chaigne, Antoine

2016-11-01

A method is presented for reconstructing piano hammer forces through appropriate filtering of the measured string velocity. The filter design is based on the analysis of the pulses generated by the hammer blow and propagating along the string. In the five lowest octaves, the hammer force is reconstructed by considering two waves only: the incoming wave from the hammer and its first reflection at the front end. For the higher notes, four- or eight-wave schemes must be considered. The theory is validated on simulated string velocities by comparing imposed and reconstructed forces. The simulations are based on a nonlinear damped stiff string model previously developed by Chabassier, Chaigne, and Joly [J. Acoust. Soc. Am. 134(1), 648-665 (2013)]. The influence of absorption, dispersion, and amplitude of the string waves on the quality of the reconstruction is discussed. Finally, the method is applied to real piano strings. The measured string velocity is compared to the simulated velocity excited by the reconstructed force, showing a high degree of accuracy. A number of simulations are compared to simulated strings excited by a force derived from measurements of mass and acceleration of the hammer head. One application to an historic piano is also presented.

Screening reactor steam/water piping systems for water hammer

International Nuclear Information System (INIS)

Griffith, P.

1997-09-01

A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greater than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made

40 CFR 194.33 - Consideration of drilling events in performance assessments.

Science.gov (United States)

2010-07-01

... assessments. (a) Performance assessments shall examine deep drilling and shallow drilling that may potentially affect the disposal system during the regulatory time frame. (b) The following assumptions and process... process shall be documented in any compliance application: (1) Inadvertent and intermittent intrusion by...

Comparative evaluation of recent water hammer events in light water reactors

International Nuclear Information System (INIS)

House, R.K.; Sursock, J.P.; Kim, J.H.

1987-01-01

Water hammer events that occurred in commercial U.S. light water reactors in the five-year period from 1981 to 1985 were surveyed, and a preliminary evaluation of the events was conducted. The information developed supplements a previous study which evaluated water hammer events in the twelve-year period from 1969 to 1981. The current study of water hammer events in the 1980's confirms that the rate of events remains relatively constant (less than 0.25 events per plant year) in both PWRs and BWRs. Although water hammer events are not normally considered a safety issue, the economic impact of the events on plant operations can be significant. One particular severe water hammer event is estimated to have cost the plant owner $10 million for repair and evaluation alone. A variety of key characteristics of the recent water hammer events are summarized to establish a basis for further study of preventative methods

A new production technique for wear resistant ring-hammers

Directory of Open Access Journals (Sweden)

Li Shifeng

2011-11-01

Full Text Available Based on a great number of laboratory experiments, a new technique has been developed for producing wear resistant ring-hammers. In this technology, lost foam casting with iron sand was combined to make mold; a special alloy was used to inoculate the molten steel, and proper heat treatment was used to further improve mechanical properties of wear resistant ring-hammers. The influence of this new production technology on the microstructure and mechanical properties of wear resistant ring-hammers was studied. Results show that iron sand molding, having the inherent characteristic of sand molding, changes the type of metallic compounds, refines crystal grains and increases the fineness of microstructure. Practical experience verified that the properties of the ring-hammers produced with this new technique are as follows: tensile strength (Rm 720 MPa, impact toughness (ak > 210 J•cm-2 and hardness > 200 HB. After water quenching from 1,080℃ (holding for 4 h and tempering at 320℃ for 3 h, the best wear resistance is obtained, and the wear resistance is 1.6 times higher than that of common high manganese ring-hammers.

Pressurized water-reactor feedwater piping response to water hammer

International Nuclear Information System (INIS)

Arthur, D.

1978-03-01

The nuclear power industry is interested in steam-generator water hammer because it has damaged the piping and components at pressurized water reactors (PWRs). Water hammer arises when rapid steam condensation in the steam-generator feedwater inlet of a PWR causes depressurization, water-slug acceleration, and slug impact at the nearest pipe elbow. The resulting pressure pulse causes the pipe system to shake, sometimes violently. The objective of this study is to evaluate the potential structural effects of steam-generator water hammer on feedwater piping. This was accomplished by finite-element computation of the response of two sections of a typical feedwater pipe system to four representative water-hammer pulses. All four pulses produced high shear and bending stresses in both sections of pipe. Maximum calculated pipe stresses varied because the sections had different characteristics and were sensitive to boundary-condition modeling

Goal Translation for a Hammer for Coq (Extended Abstract

Directory of Open Access Journals (Sweden)

Łukasz Czajka

2016-06-01

Full Text Available Hammers are tools that provide general purpose automation for formal proof assistants. Despite the gaining popularity of the more advanced versions of type theory, there are no hammers for such systems. We present an extension of the various hammer components to type theory: (i a translation of a significant part of the Coq logic into the format of automated proof systems; (ii a proof reconstruction mechanism based on a Ben-Yelles-type algorithm combined with limited rewriting, congruence closure and a first-order generalization of the left rules of Dyckhoff's system LJT.

Water hammer characteristics of integral pressurized water reactor primary loop

International Nuclear Information System (INIS)

Zuo, Qiaolin; Qiu, Suizheng; Lu, Wei; Tian, Wenxi; Su, Guanghui; Xiao, Zejun

2013-01-01

Highlights: • Water hammer models developed for IPWR primary loop using MOC. • Good agreement between the developed code and the experiment. • The good agreement between WAHAP and Flowmaster can validate the equations in WAHAP. • The primary loop of IPWR suffers from slight water hammer impact. -- Abstract: The present work discussed the single-phase water hammer phenomenon, which was caused by the four-pump-alternate startup in an integral pressurized water reactor (IPWR). A new code named water hammer program (WAHAP) was developed independently based on the method of characteristic to simulate hydraulic transients in the primary system of IPWR and its components such as reactor core, once-through steam generators (OTSG), the main coolant pumps and so on. Experimental validation for the correctness of the equations and models in WAHAP was carried out and the models fit the experimental data well. Some important variables were monitored including transient volume flow rates, opening angle of valve disc and pressure drop in valves. The water hammer commercial software Flowmaster V7 was also employed to compare with WAHAP and the good agreement can validate the equations in WAHAP. The transient results indicated that the primary loop of IPWR suffers from slight water hammer impact under pump switching conditions

Water hammer characteristics of integral pressurized water reactor primary loop

Energy Technology Data Exchange (ETDEWEB)

Zuo, Qiaolin [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Qiu, Suizheng, E-mail: szqiu@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Lu, Wei; Tian, Wenxi; Su, Guanghui [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an, Shanxi 710049 (China); Xiao, Zejun [Nuclear Power Institute of China, Chengdu, Sichuan 610041 (China)

2013-08-15

Highlights: • Water hammer models developed for IPWR primary loop using MOC. • Good agreement between the developed code and the experiment. • The good agreement between WAHAP and Flowmaster can validate the equations in WAHAP. • The primary loop of IPWR suffers from slight water hammer impact. -- Abstract: The present work discussed the single-phase water hammer phenomenon, which was caused by the four-pump-alternate startup in an integral pressurized water reactor (IPWR). A new code named water hammer program (WAHAP) was developed independently based on the method of characteristic to simulate hydraulic transients in the primary system of IPWR and its components such as reactor core, once-through steam generators (OTSG), the main coolant pumps and so on. Experimental validation for the correctness of the equations and models in WAHAP was carried out and the models fit the experimental data well. Some important variables were monitored including transient volume flow rates, opening angle of valve disc and pressure drop in valves. The water hammer commercial software Flowmaster V7 was also employed to compare with WAHAP and the good agreement can validate the equations in WAHAP. The transient results indicated that the primary loop of IPWR suffers from slight water hammer impact under pump switching conditions.

A wireless sensor system for a biofeedback training of hammer throwers.

Science.gov (United States)

Wang, Ye; Wan, Bingjun; Li, Hua; Shan, Gongbing

2016-01-01

Hammer-throw has a long-standing history in track and field, but unlike some other sports events, men's hammer throw has not seen a new world record since 1986. One of the possible reasons for this stagnation could be the lack of real-time biomechanical feedback training. In this study, we proposed to establish scientifically described training targets and routes, which in turn required tools that could measure and quantify characteristics of an effective hammer-throw. Towards this goal, we have developed a real-time biomechanical feedback device-a wireless sensor system-to help the training of hammer-throw. The system includes two sensors-an infrared proximity sensor for tracing the hip vertical movement and a load cell for recording the wire tension during a hammer-throw. The system uses XBees for data transmission and an Arduino processor for data processing and system control. The results revealed that the wire tension measurement could supply sufficient key features for coaches to analyze hammer-throw and give real-time feedback for improving training efficiency.

The Velvet Hammer

Science.gov (United States)

Henderson, Nancy

2008-01-01

This article features the life of Louise Underwood, an advocate for people with disabilities and their families. Underwood is known for her nickname "The Velvet Hammer" because of her relentless attitude when it comes to advocating for people with disabilities. Many times she has pulled strings to halt legislation that would have…

Overview of Prevention for Water Hammer by Check Valve Action in Nuclear Reactor

International Nuclear Information System (INIS)

Kim, Dayong; Yoon, Hyungi; Seo, Kyoungwoo; Kim, Seonhoon

2016-01-01

Water hammer can cause serious damage to pumping system and unexpected system pressure rise in the pipeline. In nuclear reactor, water hammer can influence on the integrity of safety related system. Water hammer in nuclear reactor have been caused by voiding in normally water-filled lines, steam condensation line containing both steam and water, as well as by rapid check valve action. Therefore, this study focuses on the water hammer by check valve among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. This study focuses on the water hammer by check valve action among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. If the inadvertent pump trip or pipe rupture in high velocity and pressure pipe is predicted, the fast response check valve such as tiled disc, dual disc and nozzle check valve should be installed in the system. If the inadvertent pump trip or pipe rupture in very high velocity and pressure pipe and excessively large revered flow velocity are predicted, the very slowly closing check valve such as controlled closure check valve should be installed in the system

Overview of Prevention for Water Hammer by Check Valve Action in Nuclear Reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, Dayong; Yoon, Hyungi; Seo, Kyoungwoo; Kim, Seonhoon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Water hammer can cause serious damage to pumping system and unexpected system pressure rise in the pipeline. In nuclear reactor, water hammer can influence on the integrity of safety related system. Water hammer in nuclear reactor have been caused by voiding in normally water-filled lines, steam condensation line containing both steam and water, as well as by rapid check valve action. Therefore, this study focuses on the water hammer by check valve among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. This study focuses on the water hammer by check valve action among the sources of water hammer occurrence and suggests proper methodology for check valve type selection against water hammer. If the inadvertent pump trip or pipe rupture in high velocity and pressure pipe is predicted, the fast response check valve such as tiled disc, dual disc and nozzle check valve should be installed in the system. If the inadvertent pump trip or pipe rupture in very high velocity and pressure pipe and excessively large revered flow velocity are predicted, the very slowly closing check valve such as controlled closure check valve should be installed in the system.

A body is not a metaphor: Barbara Hammer's X-ray vision.

Science.gov (United States)

Osterweil, Ara

2010-01-01

This article examines three films by legendary experimental filmmaker Barbara Hammer that deal with the sick, aging, or dying body: Optic Nerve (1985), Sanctus (1990), and A Horse is Not a Metaphor (2008). By analyzing films that do not explicitly confront sexual identity, this article questions the continuing usefulness of the designation "lesbian filmmaker" when considering Hammer's diverse body of work. Tracing the "double consciousness" through which Hammer approaches the body and its construction in patriarchy-particularly in the discourse of medicine-this article argues that Hammer's is a thoroughly corporeal, but not exclusively lesbian, cinema.

The Hammer-and-Nail Phenomenon in Mathematics Education

Science.gov (United States)

Lim, Kien H.

2012-01-01

This paper uses the hammer-and-nail metaphor to highlight the rigidity and impulsiveness that can be found in student mathematical behaviour. The hammer-and-nail phenomenon can be attributed to two plausible causes: (1) the way the human mind works; and (2) the way mathematics is traditionally taught in school. In this paper, the following aspects…

Regulatory analysis for USI A-1, Water Hammer

International Nuclear Information System (INIS)

Serkiz, A.W.

1984-03-01

This is the staff's regulatory analysis dealing with the resolution of the Unresolved Safety Issue A-1, Water Hammer. This report contains the value-impact analysis for this issue, public comments received, and staff response, or action taken, in response to those comments. The staff's technical findings regarding water hammer in nuclear power plants are contained in NUREG-0927

Analysis and prevention of water hammer for the emergency core cooling system

International Nuclear Information System (INIS)

Zhao Jun

2008-01-01

Emergency core cooling system (ECCS) is an engineered safety feature of nuclear power plant. If the water hammer happens during ECCS injection, the piping system may be broken. It will cause loss of ECC system and affect the safety of reactor core. Based on the functions and characteristics of ECCS and the theory of water hammer, the paper analyzed the potential risk of water hammer in ECCS in Qinshan III, and proposed modifications to prevent the water-hammer damage during ECCS injection. (authors)

Numerical and in-situ investigations of water hammer effects in Drava river Kaplan turbine hydropower plants

International Nuclear Information System (INIS)

Bergant, A; Gregorc, B; Gale, J

2012-01-01

This paper deals with critical flow regimes that may induce unacceptable water hammer in Kaplan turbine hydropower plants. Water hammer analysis should be performed for normal, emergency and catastrophic operating conditions. Hydropower plants with Kaplan turbines are usually comprised of relatively short inlet and outlet conduits. The rigid water hammer theory can be used for this case. For hydropower plants with long penstocks the elastic water hammer should be used. Some Kaplan turbine units are installed in systems with long open channels. In this case, water level oscillations in the channels should be carefully investigated. Computational results are compared with results of measurements in recently rehabilitated seven Drava river hydroelectric power plants in Slovenia. Water hammer in the six power plants is controlled by appropriate adjustment of the wicket gates and runner blades closing/opening manoeuvres. Due to very long inflow and outflow open channels in Zlatolicje HPP a special vaned pressure regulating device attenuates extreme pressures in Kaplan turbine flow-passage system and controls unsteady flow in both open channels. Comparisons of results include normal operating regimes. The agreement between computed and measured results is reasonable.

Numerical and in-situ investigations of water hammer effects in Drava river Kaplan turbine hydropower plants

Science.gov (United States)

Bergant, A.; Gregorc, B.; Gale, J.

2012-11-01

This paper deals with critical flow regimes that may induce unacceptable water hammer in Kaplan turbine hydropower plants. Water hammer analysis should be performed for normal, emergency and catastrophic operating conditions. Hydropower plants with Kaplan turbines are usually comprised of relatively short inlet and outlet conduits. The rigid water hammer theory can be used for this case. For hydropower plants with long penstocks the elastic water hammer should be used. Some Kaplan turbine units are installed in systems with long open channels. In this case, water level oscillations in the channels should be carefully investigated. Computational results are compared with results of measurements in recently rehabilitated seven Drava river hydroelectric power plants in Slovenia. Water hammer in the six power plants is controlled by appropriate adjustment of the wicket gates and runner blades closing/opening manoeuvres. Due to very long inflow and outflow open channels in Zlatoličje HPP a special vaned pressure regulating device attenuates extreme pressures in Kaplan turbine flow-passage system and controls unsteady flow in both open channels. Comparisons of results include normal operating regimes. The agreement between computed and measured results is reasonable.

Water hammer conservatisms

International Nuclear Information System (INIS)

Uffer, R.A.

1993-01-01

Calculated water hammer forces often contain excessive conservatisms resulting in unrealistic damage predictions. This is especially true for void filling and column separation scenarios. Pressure rise times can be as important as pressure amplitudes. Forces based on in situ test data can also contain excessive conservatisms. This paper discusses the causes of such conservatisms and means of minimizing them

Hammering Does Not Fit Fitts' Law

Directory of Open Access Journals (Sweden)

Tadej Petrič

2017-05-01

Full Text Available While movement is essential to human wellbeing, we are still unable to reproduce the deftness and robustness of human movement in automatons or completely restore function to individuals with many types of motor impairment. To better understand how the human nervous system plans and controls movements, neuromechanists employ simple tasks such as upper extremity reaches and isometric force tasks. However, these simple tasks rarely consider impacts and may not capture aspects of motor control that arise from real-world complexity. Here we compared existing models of motor control with the results of a periodic targeted impact task extended from Bernstein's seminal work: hammering a nail into wood. We recorded impact forces and kinematics from 10 subjects hammering at different frequencies and with hammers with different physical properties (mass and face area. We found few statistical differences in most measures between different types of hammer, demonstrating human robustness to minor changes in dynamics. Because human motor control is thought to obey optimality principles, we also developed a feedforward optimal simulation with a neuromechanically inspired cost function that reproduces the experimental data. However, Fitts' Law, which relates movement time to distance traveled and target size, did not match our experimental data. We therefore propose a new model in which the distance moved is a logarithmic function of the time to move that yields better results (R2 ≥ 0.99 compared to R2 ≥ 0.88. These results support the argument that humans control movement in an optimal way, but suggest that Fitts' Law may not generalize to periodic impact tasks.

Volpentest HAMMER Federal Training Center

Data.gov (United States)

Federal Laboratory Consortium — HAMMER stands for Hazardous Materials Management and Emergency Response, and was named for Sam Volpentest, a long-time community leader and advocate of the Hanford...

Performance of the mineral blended ester oil-based drilling fluid systems

Energy Technology Data Exchange (ETDEWEB)

Ismail, A.R.; Kamis, A.; Foo, K.S. [University Teknologi (Malaysia)

2001-06-01

A study was conducted in which the properties of ester oil-based drilling fluid systems were examined using a blended mixture of ester and synthetic mineral oil. Biodegradable invert emulsion ester-based fluids are preferred over mineral oil-based drilling fluids for environmental reasons, but they tend to cause alkaline hydrolysis resulting in solidification of the drilling fluid systems. The drilling fluid examined here consisted of Malaysian palm oil ester derivatives (methyl laureate ester or isopropyl laureate ester) blended with commercially available synthetic mineral oil. This mineral oil was added to reduce the problem of alkaline hydrolysis. This mixture, however, was found to be unstable and could not solve the problem at high temperature. The isopropyl laureate and mineral oil blended system was more stable towards the hydrolysis process up to 250 degrees F. In order to enhance the performance of an invert emulsion drilling fluid system, it was recommended that brine water content of the fluid system be lowered. 3 refs., 2 figs.

Unusual Cases of Hypothenar Hammer Syndrome.

Science.gov (United States)

Orrapin, Saranat; Arworn, Supapong; Wisetborisut, Anawat

2015-01-01

Hypothenar hammer syndrome (HHS) is a rare occupational disease. The risk group of HHS is patient whose dominate hand used as a hammer. Our study report unusually cases in Chiang Mai University Hospital. 19 year-old basketball player had right ulnar artery aneurysm for two months. After operation, his symptom was relieved and returned to play basketball again. 65 year-old housekeeper had non-dominated hand ulnar artery aneurysm for two years. After operation she still had hand claudication due to poor run-off vessel. HHS is previously state in risk group. But from our report there was a risk in different occupation.

Evaluation of accuracy in implant site preparation performed in single- or multi-step drilling procedures.

Science.gov (United States)

Marheineke, Nadine; Scherer, Uta; Rücker, Martin; von See, Constantin; Rahlf, Björn; Gellrich, Nils-Claudius; Stoetzer, Marcus

2018-06-01

Dental implant failure and insufficient osseointegration are proven results of mechanical and thermal damage during the surgery process. We herein performed a comparative study of a less invasive single-step drilling preparation protocol and a conventional multiple drilling sequence. Accuracy of drilling holes was precisely analyzed and the influence of different levels of expertise of the handlers and additional use of drill template guidance was evaluated. Six experimental groups, deployed in an osseous study model, were representing template-guided and freehanded drilling actions in a stepwise drilling procedure in comparison to a single-drill protocol. Each experimental condition was studied by the drilling actions of respectively three persons without surgical knowledge as well as three highly experienced oral surgeons. Drilling actions were performed and diameters were recorded with a precision measuring instrument. Less experienced operators were able to significantly increase the drilling accuracy using a guiding template, especially when multi-step preparations are performed. Improved accuracy without template guidance was observed when experienced operators were executing single-step versus multi-step technique. Single-step drilling protocols have shown to produce more accurate results than multi-step procedures. The outcome of any protocol can be further improved by use of guiding templates. Operator experience can be a contributing factor. Single-step preparations are less invasive and are promoting osseointegration. Even highly experienced surgeons are achieving higher levels of accuracy by combining this technique with template guidance. Hereby template guidance enables a reduction of hands-on time and side effects during surgery and lead to a more predictable clinical diameter.

Evaluation of Relationships between Drilling Rate Index and Physical and Strength Properties of Selected Rock Units of Pakistan

International Nuclear Information System (INIS)

Shafique, U.; Abu Bakar, M. Z.

2015-01-01

Fifteen selected rock types collected from different formations of Pakistan were subjected to Drilling Rate Index (DRI) tests and various physical and strength properties tests including, porosity (n), density, primary wave velocity (V/sub p/), uniaxial compressive strength (sigma/sub c/), Brazilian tensile strength (sigma/sub t/) and Schmidt hammer rebound number (R/sub n/),. Prior knowledge of the drill ability of rocks and their physico-mechanical properties plays a decisive role in planning and design of rock drilling and excavation processes. DRI tests developed by NTNU/SINTEF are in use by the industry since 1960s and have proved very successful in estimation of the boreability of rocks, but no such work has been reported for Pakistani rocks to date. Reasonable correlations were found between the DRI and the properties of the tested rocks. The trends shown in this paper are of interest for the machine manufacturers and operators working on various projects involving the use of drilling machines and other mechanical excavators. (author)

Do chimpanzees use weight to select hammer tools?

Directory of Open Access Journals (Sweden)

Cornelia Schrauf

Full Text Available The extent to which tool-using animals take into account relevant task parameters is poorly understood. Nut cracking is one of the most complex forms of tool use, the choice of an adequate hammer being a critical aspect in success. Several properties make a hammer suitable for nut cracking, with weight being a key factor in determining the impact of a strike; in general, the greater the weight the fewer strikes required. This study experimentally investigated whether chimpanzees are able to encode the relevance of weight as a property of hammers to crack open nuts. By presenting chimpanzees with three hammers that differed solely in weight, we assessed their ability to relate the weight of the different tools with their effectiveness and thus select the most effective one(s. Our results show that chimpanzees use weight alone in selecting tools to crack open nuts and that experience clearly affects the subjects' attentiveness to the tool properties that are relevant for the task at hand. Chimpanzees can encode the requirements that a nut-cracking tool should meet (in terms of weight to be effective.

Impact of Drill and Blast Excavation on Repository Performance Confirmation

International Nuclear Information System (INIS)

Keller, R.; Francis, N.; Houseworth, J.; Kramer, N.

2000-01-01

There has been considerable work accomplished internationally examining the effects of drill and blast excavation on rock masses surrounding emplacement openings of proposed nuclear waste repositories. However, there has been limited discussion tying the previous work to performance confirmation models such as those proposed for Yucca Mountain, Nevada. This paper addresses a possible approach to joining the available information on drill and blast excavation and performance confirmation. The method for coupling rock damage data from drill and blast models to performance assessment models for fracture flow requires a correlation representing the functional relationship between the peak particle velocity (PPV) vibration levels and the potential properties that govern water flow rates in the host rock. Fracture aperture and frequency are the rock properties which may be most influenced by drill and blast induced vibration. If it can be shown (using an appropriate blasting model simulation) that the effect of blasting is far removed from the waste package in an emplacement drift, then disturbance to the host rock induced in the process of drill and blast excavation may be reasonably ignored in performance assessment calculations. This paper proposes that the CANMET (Canada Center for Mineral and Energy Technology) Criterion, based on properties that determine rock strength, may be used to define a minimum PPV. This PPV can be used to delineate the extent of blast induced damage. Initial applications have demonstrated that blasting models can successfully be coupled with this criterion to predict blast damage surrounding underground openings. The Exploratory Studies Facility at Yucca Mountain has used a blasting model to generate meaningful estimates of near-field vibration levels and damage envelopes correlating to data collected from pre-existing studies conducted. Further work is underway to expand this application over a statistical distribution of geologic

Condensate induced water hammer in a steam distribution system results in fatality

International Nuclear Information System (INIS)

Debban, H.L.; Eyre, L.E.

1996-02-01

Water hammer event s in steam distribution piping interrupt service and have the potential to cause serious injury and property damage. Conditions of condensation induced water hammer are discussed and recommendations aimed to improve safety of steam systems are presented. Condensate induced water hammer events at Hanford, a DOE facility, are examined

Assessment of Analytic Water hammer Pressure Model of FAI/08-70

International Nuclear Information System (INIS)

Park, Ju Yeop; Yoo, Seung Hun; Seul, Kwang-Won

2016-01-01

In evaluating water hammer effect on the safety related systems, methods developed by the US utility are likely to be adopted in Korea. For example, the US utility developed specific methods to evaluate pressure and loading transient on piping due to water hammer as in FAI/08-70. The methods of FAI/08-70 would be applied in Korea when any regulatory request on the evaluation of water hammer effect due to the non-condensable gas accumulation in the safety related systems. Specifically, FAI/08-70 gives an analytic model which can be used to analyze the maximum transient pressure and maximum transient loading on the piping of the safety-related systems due to the non-condensable induced water hammer effect. Therefore, it seems to be meaningful to review the FAI/08-70 methods and attempt to apply the methods to a specific case to see if they really give reasonable estimate before the application of FAI/08-70 methods to domestic nuclear power plants. In the present study, analytic water hammer pressure model of FAI/08-70 is reviewed in detail and the model is applied to the specific experiment of FAI/08-70 to see if the analytic water hammer pressure model really gives reasonable estimate of the peak water hammer pressure. Specifically, we assess the experiment 52A of FAI/08-70 which adopts flushed initial condition with a short rising piping length and a high level piping length of 51inch. The calculated analytic water hammer pressure peak shows a close agreement with the measured experimental data of 52A. Unfortunately, however, the theoretical value is a little bit less than that of the experimental value. This implies the analytic model of FAI/08-70 is not conservative

Assessment of Analytic Water hammer Pressure Model of FAI/08-70

Energy Technology Data Exchange (ETDEWEB)

Park, Ju Yeop; Yoo, Seung Hun; Seul, Kwang-Won [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

2016-10-15

In evaluating water hammer effect on the safety related systems, methods developed by the US utility are likely to be adopted in Korea. For example, the US utility developed specific methods to evaluate pressure and loading transient on piping due to water hammer as in FAI/08-70. The methods of FAI/08-70 would be applied in Korea when any regulatory request on the evaluation of water hammer effect due to the non-condensable gas accumulation in the safety related systems. Specifically, FAI/08-70 gives an analytic model which can be used to analyze the maximum transient pressure and maximum transient loading on the piping of the safety-related systems due to the non-condensable induced water hammer effect. Therefore, it seems to be meaningful to review the FAI/08-70 methods and attempt to apply the methods to a specific case to see if they really give reasonable estimate before the application of FAI/08-70 methods to domestic nuclear power plants. In the present study, analytic water hammer pressure model of FAI/08-70 is reviewed in detail and the model is applied to the specific experiment of FAI/08-70 to see if the analytic water hammer pressure model really gives reasonable estimate of the peak water hammer pressure. Specifically, we assess the experiment 52A of FAI/08-70 which adopts flushed initial condition with a short rising piping length and a high level piping length of 51inch. The calculated analytic water hammer pressure peak shows a close agreement with the measured experimental data of 52A. Unfortunately, however, the theoretical value is a little bit less than that of the experimental value. This implies the analytic model of FAI/08-70 is not conservative.

Saturation of plastic deformation by swift heavy ion irradiation: Ion hammering vs. surface effects

Energy Technology Data Exchange (ETDEWEB)

Ferhati, Redi; Dautel, Knut; Bolse, Wolfgang [Institut fuer Halbleiteroptik und Funktionelle Grenzflaechen, Universitaet Stuttgart (Germany); Fritzsche, Monika [Helmholtz-Zentrum Dresden-Rossendorf (Germany)

2012-07-01

Swift heavy ion (SHI) induced plastic deformation is a subject of current research and scientific discussion. This *Ion Hammering* phenomenon was first observed 30 years ago in amorphous materials like metallic glasses. About 10 years ago, Feyh et al. have shown that stress generation and *Ion Hammering* result in self-organization of thin NiO-films on Si-wafers into a sub-micron lamellae-like structure under grazing angle irradiation. The growth of the lamellae was found to saturate as soon as they have reached a thickness of a few hundreds of nm. Here we show our latest results on the restructuring of pre-patterned thin oxide films by SHI under various irradiation conditions. The experiments were performed by employing (in-situ) scanning electron microscopy, and were complemented by (in-situ) energy dispersive x-ray analysis and atomic force microscopy. As we will show, the saturation behavior can be understood as a competition of *Ion Hammering* and surface energy effects, while the unexpected fact, that the initially crystalline films undergo *Ion Hammering* can possibly be attributed to oxygen loss and thus amorphization during irradiation.

Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

Energy Technology Data Exchange (ETDEWEB)

Lee, Seungchan; Yoon, Dukjoo [Korea Hydro and Nuclear Power Co., LTd, Daejeon (Korea, Republic of); Lee, Dooyong [Seoul National Univ., Seoul (Korea, Republic of)

2013-05-15

Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above.

Gas-Induced Water-hammer Loads Calculation for Safety Related Systems

International Nuclear Information System (INIS)

Lee, Seungchan; Yoon, Dukjoo; Lee, Dooyong

2013-01-01

Of particular interest, gas accumulation can result in system pressure transient in pump discharge piping following a pump start. Consequently, this evolves into a gas-water, a water-hammer event and the accompanying force imbalances on the piping segments can be sufficient to challenge the piping supports and restraint. This paper describes an method performing to the water-hammer loads to determine the maximum loading that would occur in the piping system following the safety injection signal and to evaluate its integrity. For a given gas void volumes in the discharge piping, the result of the calculation shows the maximum loads of 18,894.2psi, which is smaller than the allowable criteria. Also, the maximum peak axial force imbalances acting on the support is 1,720lbf as above

Systematic methodology for diagnosis of water hammer in LWR power plants

International Nuclear Information System (INIS)

Safwat, H.H.; Arastu, A.H.; Husaini, S.M.

1990-01-01

The paper gives the dimensions of the knowledge base that is necessary to carry out a diagnosis of water hammer susceptibility/root cause analyses for Pressurized Water Reactor (PWR) and Boiling Water Reactor (BWR) nuclear power plant systems. After introducing some fundamentals, water hammer phenomena are described. Situations where each phenomenon is encountered are given and analytical models capable of simulating the phenomena are referenced. Water hammer events in operating plants and their inclusion in the knowledge base is discussed. The diagnostic methodology is presented through an application on a system in a typical light water reactor plant. The methodology presented serves as a possible foundation for the creation of an expert water hammer diagnosis system. (orig.)

Condensation induced water hammer safety

International Nuclear Information System (INIS)

Gintner, M.A.

1997-01-01

Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer

Influence of fluiddynamic parameters upon fluid-hammer forces and spectra

International Nuclear Information System (INIS)

Meder, G.; Grams, J.

1984-01-01

For proper dynamic calculation of piping systems under fluid-hammer loading it is necessary to know the frequency content of the fluid-hammer force. Therefore, in this paper, the spectra of fluid-hammer loading will be examined. In particular, the influence of a change of fluiddynamic parameters upon the spectra will be investigated. When changes are made, the normal result is a change or shift in the frequency content of the spectra. However, for changes in certain fluiddynamic parameters, only the force amplitudes are changed. Both types of changes will be discussed. (orig.)

Real Time Seismic Prediction while Drilling

Science.gov (United States)

Schilling, F. R.; Bohlen, T.; Edelmann, T.; Kassel, A.; Heim, A.; Gehring, M.; Lüth, S.; Giese, R.; Jaksch, K.; Rechlin, A.; Kopf, M.; Stahlmann, J.; Gattermann, J.; Bruns, B.

2009-12-01

Efficient and safe drilling is a prerequisite to enhance the mobility of people and goods, to improve the traffic as well as utility infrastructure of growing megacities, and to ensure the growing energy demand while building geothermal and in hydroelectric power plants. Construction within the underground is often building within the unknown. An enhanced risk potential for people and the underground building may arise if drilling enters fracture zones, karsts, brittle rocks, mixed solid and soft rocks, caves, or anthropogenic obstacles. Knowing about the material behavior ahead of the drilling allows reducing the risk during drilling and construction operation. In drilling operations direct observations from boreholes can be complemented with geophysical investigations. In this presentation we focus on “real time” seismic prediction while drilling which is seen as a prerequisite while using geophysical methods in modern drilling operations. In solid rocks P- and S-wave velocity, refraction and reflection as well as seismic wave attenuation can be used for the interpretation of structures ahead of the drilling. An Integrated Seismic Imaging System (ISIS) for exploration ahead of a construction is used, where a pneumatic hammer or a magnetostrictive vibration source generate repetitive signals behind the tunneling machine. Tube waves are generated which travel along the tunnel to the working face. There the tube waves are converted to mainly S- but also P-Waves which interact with the formation ahead of the heading face. The reflected or refracted waves travel back to the working front are converted back to tube waves and recorded using three-component geophones which are fit into the tips of anchor rods. In near real time, the ISIS software allows for an integrated 3D imaging and interpretation of the observed data, geological and geotechnical parameters. Fracture zones, heterogeneities, and variations in the rock properties can be revealed during the drilling

Reducing forces during drilling brittle hard materials by using ultrasonic and variation of coolant

Science.gov (United States)

Schopf, C.; Rascher, R.

2016-11-01

The process of ultrasonic machining is especially used for brittle hard materials as the additional ultrasonic vibration of the tool at high frequencies and low amplitudes acts like a hammer on the surface. With this technology it is possible to drill holes with lower forces, therefor the machining can be done faster and the worktime is much less than conventionally. A three-axis dynamometer was used to measure the forces, which act between the tool and the sample part. A focus is set on the sharpness of the tool. The results of a test series are based on the Sauer Ultrasonic Grinding Centre. On the same machine it is possible to drill holes in the conventional way. Additional to the ultasonic Input the type an concentration of coolant is important for the Drilling-force. In the test there were three different coolant and three different concentrations tested. The combination of ultrasonic vibration and the right coolant and concentration is the best way to reduce the Forces. Another positive effect is, that lower drilling-forces produce smaller chipping on the edge of the hole. The way to reduce the forces and chipping is the main issue of this paper.

Performance of Partially-Hydrolyzed Polyacrylamide in Water Based Drilling Fluids

Directory of Open Access Journals (Sweden)

Ali Reza Nasiri*

2013-05-01

Full Text Available Fluid properties with constant improvement in efficiency have been noticeable as important criteria in drilling operation. The main drilling fluid properties highly depend on utilization of new polymers with high efficiency in drilling fluid composition. In this paper, the performance of a new polymer, called partially hydrolyzed polyacrylamide polymer (PHPA, is studied which has recently entered the drilling fluids industry in Iran. Hence viscosity property, fluid loss control and shale inhibition of this polymer have been evaluated based on an international standard method of API-13-I by considering the drilling and operational priorities of thecountry. Then the thermal effect, salt contaminants such as sodium chloride, calcium chloride, magnesium chloride and pH tolerance effect as major pollution indicators are also investigated in relation to polymeric fluid properties. The results obtained by the tests show that furthermore polymer PHPA increases rheological properties (apparent viscosity, plastic fluidity and yield point and it plays important role in increases in fluid loss. This polymer has also demonstrated acceptable resistance toward sodium chloride contaminants, but its efficiency decreases toward calcium and magnesium ion contaminants. The thermal tests show that polymer PHPA has high thermal stability up to 150°C. This polymer improves shale inhibition property and by encapsulation mechanism prevents dispersion of shale cuttings into the drilling fluid system as it stops any changes in fluid properties which will finally results inwellbore stability.

Load and wear experiments on the impact hammer of a vertical shaft impact crusher

International Nuclear Information System (INIS)

Yang, J H; Fang, H Y; Luo, M

2015-01-01

Impact hammers are important components of impact crushers, and are often shortlived due to the high-impact nature of their use. Wear-resistant alloys are welded to the surface of impact hammers to prolong their service life. In this paper, a simulation model of the rotor and impact hammers in impact crushers was designed to utilize the Discrete Element Method (DEM). The wear-resistant alloy on each impact hammer was divided into twenty-two action regions. The load distribution on each alloy block is affected by the structural and manufacturing parameters of the impact crusher. The wear distribution of the impact hammer was measured by shape morphology according to relative impact crushers. The results demonstrated that the real measurements of wear distribution on the impact hammer were similar to simulated load distribution measurements on the same surface. The study of load distribution of impact hammers by DEM established a theoretical foundation on which to base the optimal design of impact crushers. (paper)

Chebyshev super spectral viscosity method for water hammer analysis

Directory of Open Access Journals (Sweden)

Hongyu Chen

2013-09-01

Full Text Available In this paper, a new fast and efficient algorithm, Chebyshev super spectral viscosity (SSV method, is introduced to solve the water hammer equations. Compared with standard spectral method, the method's advantage essentially consists in adding a super spectral viscosity to the equations for the high wave numbers of the numerical solution. It can stabilize the numerical oscillation (Gibbs phenomenon and improve the computational efficiency while discontinuities appear in the solution. Results obtained from the Chebyshev super spectral viscosity method exhibit greater consistency with conventional water hammer calculations. It shows that this new numerical method offers an alternative way to investigate the behavior of the water hammer in propellant pipelines.

Grid site testing for ATLAS with HammerCloud

International Nuclear Information System (INIS)

Elmsheuser, J; Hönig, F; Legger, F; LLamas, R Medrano; Sciacca, F G; Ster, D van der

2014-01-01

With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling virtual organisations (VO) and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test workflows. These new workflows comprise e.g. tests of the ATLAS nightly build system, ATLAS Monte Carlo production system, XRootD federation (FAX) and new site stress test workflows. We report on the development, optimization and results of the various components in the HammerCloud framework.

Grid Site Testing for ATLAS with HammerCloud

CERN Document Server

Elmsheuser, J; The ATLAS collaboration; Legger, F; Medrano LLamas, R; Sciacca, G; van der Ster, D

2014-01-01

With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test work-flows. These new work-flows comprise e.g. tests of the ATLAS nightly build system, ATLAS MC production system, XRootD federation FAX and new site stress test work-flows. We report on the development, optimization and results of the various components in the HammerCloud framework.

Grid Site Testing for ATLAS with HammerCloud

CERN Document Server

Elmsheuser, J; The ATLAS collaboration; Legger, F; Medrano LLamas, R; Sciacca, G; van der Ster, D

2013-01-01

With the exponential growth of LHC (Large Hadron Collider) data in 2012, distributed computing has become the established way to analyze collider data. The ATLAS grid infrastructure includes more than 130 sites worldwide, ranging from large national computing centers to smaller university clusters. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run validation tests of the site and software infrastructure in an automated or on-demand manner. The HammerCloud infrastructure has been constantly improved to support the addition of new test work-flows. These new work-flows comprise e.g. tests of the ATLAS nightly build system, ATLAS MC production system, XRootD federation FAX and new site stress test work-flows. We report on the development, optimization and results of the various components in the HammerCloud framework.

Proximal forearm extensor muscle strain is reduced when driving nails using a shock-controlled hammer.

Science.gov (United States)

Buchanan, Kimberly A; Maza, Maria; Pérez-Vázquez, Carlos E; Yen, Thomas Y; Kijowski, Richard; Liu, Fang; Radwin, Robert G

2016-10-01

Repetitive hammer use has been associated with strain and musculoskeletal injuries. This study investigated if using a shock-control hammer reduces forearm muscle strain by observing adverse physiological responses (i.e. inflammation and localized edema) after use. Three matched framing hammers were studied, including a wood-handle, steel-handle, and shock-control hammer. Fifty volunteers were randomly assigned to use one of these hammers at a fatiguing pace of one strike every second, to seat 20 nails in a wood beam. Magnetic resonance imaging was used to scan the forearm muscles for inflammation before the task, immediately after hammering, and one to two days after. Electromyogram signals were measured to estimate grip exertions and localized muscle fatigue. High-speed video was used to calculate the energy of nail strikes. While estimated grip force was similar across the three hammers, the shock-control hammer had 40% greater kinetic energy upon impact and markedly less proximal extensor muscle edema than the wood-handle and steel-handle hammers, immediately after use (phandle shock can mitigate strain in proximal forearm extensor muscles. Copyright © 2016 Elsevier Ltd. All rights reserved.

Quantifying performance on an outdoor agility drill using foot-mounted inertial measurement units.

Directory of Open Access Journals (Sweden)

Antonia M Zaferiou

Full Text Available Running agility is required for many sports and other physical tasks that demand rapid changes in body direction. Quantifying agility skill remains a challenge because measuring rapid changes of direction and quantifying agility skill from those measurements are difficult to do in ways that replicate real task/game play situations. The objectives of this study were to define and to measure agility performance for a (five-cone agility drill used within a military obstacle course using data harvested from two foot-mounted inertial measurement units (IMUs. Thirty-two recreational athletes ran an agility drill while wearing two IMUs secured to the tops of their athletic shoes. The recorded acceleration and angular rates yield estimates of the trajectories, velocities and accelerations of both feet as well as an estimate of the horizontal velocity of the body mass center. Four agility performance metrics were proposed and studied including: 1 agility drill time, 2 horizontal body speed, 3 foot trajectory turning radius, and 4 tangential body acceleration. Additionally, the average horizontal ground reaction during each footfall was estimated. We hypothesized that shorter agility drill performance time would be observed with small turning radii and large tangential acceleration ranges and body speeds. Kruskal-Wallis and mean rank post-hoc statistical analyses revealed that shorter agility drill performance times were observed with smaller turning radii and larger tangential acceleration ranges and body speeds, as hypothesized. Moreover, measurements revealed the strategies that distinguish high versus low performers. Relative to low performers, high performers used sharper turns, larger changes in body speed (larger tangential acceleration ranges, and shorter duration footfalls that generated larger horizontal ground reactions during the turn phases. Overall, this study advances the use of foot-mounted IMUs to quantify agility performance in

A Hammer-Impact, Aluminum, Shear-Wave Seismic Source

Science.gov (United States)

Haines, Seth

2007-01-01

Near-surface seismic surveys often employ hammer impacts to create seismic energy. Shear-wave surveys using horizontally polarized waves require horizontal hammer impacts against a rigid object (the source) that is coupled to the ground surface. I have designed, built, and tested a source made out of aluminum and equipped with spikes to improve coupling. The source is effective in a variety of settings, and it is relatively simple and inexpensive to build.

Modelling water hammer in viscoelastic pipelines: short brief

Science.gov (United States)

Urbanowicz, K.; Firkowski, M.; Zarzycki, Z.

2016-10-01

The model of water hammer in viscoelastic pipelines is analyzed. An appropriate mathematical model of water hammer in polymer pipelines is presented. An additional term has been added to continuity equation to describe the retarded deformation of the pipe wall. The mechanical behavior of viscoelastic material is described by generalized Kelvin-Voigt model. The comparison of numerical simulation and experimental data from well known papers is presented. Short discussion about obtained results are given.

Condensation induced water hammer safety

Energy Technology Data Exchange (ETDEWEB)

Gintner, M.A.

1997-03-10

Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer.

Improving ATLAS computing resource utilization with HammerCloud

CERN Document Server

Schovancova, Jaroslava; The ATLAS collaboration

2018-01-01

HammerCloud is a framework to commission, test, and benchmark ATLAS computing resources and components of various distributed systems with realistic full-chain experiment workflows. HammerCloud contributes to ATLAS Distributed Computing (ADC) Operations and automation efforts, providing the automated resource exclusion and recovery tools, that help re-focus operational manpower to areas which have yet to be automated, and improve utilization of available computing resources. We present recent evolution of the auto-exclusion/recovery tools: faster inclusion of new resources in testing machinery, machine learning algorithms for anomaly detection, categorized resources as master vs. slave for the purpose of blacklisting, and a tool for auto-exclusion/recovery of resources triggered by Event Service job failures that is being extended to other workflows besides the Event Service. We describe how HammerCloud helped commissioning various concepts and components of distributed systems: simplified configuration of qu...

UO2-PuO2 critical experiments based on a coupled NJOY/AMPX-II/HAMMER-TECHNION system

International Nuclear Information System (INIS)

Fernandes, M.A.R.

1990-01-01

The performance of the HAMMER-TECHNION system in the criticality analysis of mixed oxide (UO sub(2)-PuO sub(2)) fuel pins clad with Zircaloy-2 and having light water as moderator was analyzed in this work. The basic nuclear data libraries for the HAMMER-TECHNION have been generated by processing the ENDF/B-IV and JENDL-2 nuclear data files with the NJOY system. The question of the effect of Plutonium resonances close to the thermal region on the average thermal parameters was addressed by creating a special version of the HAMMER-TECHNION system with the thermal energy cut-off at 1.855 eV. The final system effective multiplication factor was calculated with the CITATION code by using the homogeneized four-group cross sections generated by the HAMMER-TECHNION system. Results are shown for the original HAMMER-TECHNION thermal cut-off and for the one at 1.855 eV. Besides that, for some selected critical systems, the effect of the resonance interference among the resonances of the Uranium and Plutonium isotopes was addressed by using the ROLAIDS module of the AMPX-II system. The effect of the thermal energy cut-off on the integral parameters of the critical systems was not found to be of extreme importance. (author)

On the Wave Stresses in the Rods of Anvil Hammers

Directory of Open Access Journals (Sweden)

V. M. Sinitskiy

2014-01-01

Full Text Available With operating anvil hammers, there are rigid impacts of die tools, and as a result, almost instantaneous impact stops of the falling parts of hammer. Such operating conditions lead to the accelerated breakdowns of rods because of significant wave stresses arising in them. Common differential and integral methods to estimate wave stresses are widespread in engineering practice. However, to use them a researcher has to possess certain skills and special software. We consider the method for estimating the wave stresses in the rods of anvil hammers based on Laplace transforms (LT of wave equation. The article shows a procedure to set up and solve differential wave equations by operator method. These equations describe the wave propagation process of strains and stresses in the rods of anvil hammers with rigid impact and taking into account a damping rod connection with the head of hammer. The method takes into consideration an influence of both piston and rod weights and of mechanical and geometrical characteristics of rod on the stress value in the placement of rod in hammer head. Results analysis shows that a sufficiently efficient method for practical improving the durability of rods is the method of damping impact load on the rod through setting the damping devices in the form either of elastic "pad" of one or another design or of hydraulic shock absorbers in the placement of its connection with the hammer head. In this case there is a change of the wave front, it becomes flatter. It is shown that the stresses in the rod are proportional to the amount of wave stresses because of the own impact of rod and piston, which make a total weight of the system. Effect of piston weight on the stresses value at the rod during impact is directly proportional to the ratio of its weight to the rod weight. The geometric parameters of rod and the speed of the falling parts before the impact also influence on the value of stresses in the rod.The represented

Hypothenar hammer syndrome in an office worker.

Science.gov (United States)

Zhang, Fan; Weerakkody, Yuranga; Tosenovsky, Patrik

2017-12-01

Hypothenar hammer syndrome (HHS) is an uncommon cause of unilateral Raynaud's phenomenon, splinter haemorrhages and hypothenar weakness. The typical patient is a male blue-collar worker who uses their hypothenar eminence to hammer objects as part of their work. The distal ulnar artery beyond Guyon's canal is superficial and vulnerable to blunt trauma. CTA and MRA are common initial investigations and can suggest the diagnosis. DSA is the gold standard imaging modality and offers therapeutic opportunities. Management is controversial, but unless there is critical digital ischaemia, conservative treatment is first line. © 2017 The Royal Australian and New Zealand College of Radiologists.

Prevention and mitigation of steam generator water hammer events in PWRs

International Nuclear Information System (INIS)

Han, J.T.; Anderson, N.

1983-01-01

Water hammer in nuclear power plants is an unresolved safety issue under study by the Nuclear Regulatory Commission (NRC). This article summarizes (1) the causes of steam generator water hammer (SGWH) events in pressurized-water reactors (PWRs), (2) various methods used to prevent or mitigate SGWH events, and (3) modifications that have been made at each operating PWR. The NRC staff considers the issue of SGWH in top feedring designs to be technically resolved. This article does not address technical findings relevant to water hammer in preheat-type steam generators

Specific Characteristics of Injuries Inflicted by Claw Hammer.

Science.gov (United States)

Buchaillet, Céline; Gaudin, Arnaud; Rougé-Maillart, Clotilde; Jousset, Nathalie

2016-09-01

Claw hammers have the specific characteristic of having two distinct ends: one a flat head of variable form, the other bifurcated. So the use of this tool as a blunt instrument will cause varying injuries. The authors present two clinical cases of assault with a claw hammer. Examinations revealed two types of wound. A first injury composed of integumentary lacerations and underlying bone injuries in terms of "shape" suggested the use of a blunt instrument. A second injury made up of damage showing two parallel wounds or two wounds located one in the extension of the other suggested the use of an object with a bifurcated end. The combination of both types of injury should alert examiners to the possibility of the use of a claw hammer in causing the injuries in order to help direct investigators in their investigations and in the search for the weapon used. © 2016 American Academy of Forensic Sciences.

Mitigating check valve slamming and subsequentwater hammer events for PPFS using MOC

International Nuclear Information System (INIS)

Tian Wenxi; Su Guanghui; Wang Gaopeng; Qiu Suizheng; Xiao Zejun

2009-01-01

The method of characteristic (MOC) was adopted to analyze the check valve-induced water hammer behaviors for a Parallel Pumps Feedwater System (PPFS) during the alternate startup process. The motion of check valve disc was simulated using inertial valve model. Transient parameters including the pressure oscillation, local flow velocity and slamming of the check valve disc etc. have been obtained. The results showed that severe slamming between the valve disc and valve seat occurred during the alternate startup of parallel pumps. The induced maximum pressure vibration amplitude is up to 5.0 MPa. The scheme of appending a damping torque to slow down the check valve closing speed was also performed to mitigate of water hammer. It has been numerically approved to be an effective approach. (authors)

Mitigating check valve slamming and subsequentwater hammer events for PPFS using MOC

Institute of Scientific and Technical Information of China (English)

TIAN Wenxi; SU Guanghui; WANG Gaopeng; QIU Suizheng; XIAO Zejun

2009-01-01

The method of characteristic (MOC) was adopted to analyze the check valve-induced water hammer behaviors for a Parallel Pumps Feedwater System (PPFS) during the alternate startup process. The motion of check valve disc was simulated using inertial valve model. Transient parameters including the pressure oscillation, local flow velocity and slamming of the check valve disc etc. have been obtained. The results showed that severe slamming between the valve disc and valve seat occurred during the alternate startup of parallel pumps. The induced maximum pressure vibration amplitude is up to 5.0 MPa. The scheme of appending a damping torque to slow down the check valve closing speed was also performed to mitigate of water hammer. It has been numerically approved to be an effective approach.

Effects of air vessel on water hammer in high-head pumping station

International Nuclear Information System (INIS)

Wang, L; Wang, F J; Zou, Z C; Li, X N; Zhang, J C

2013-01-01

Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled

Effects of air vessel on water hammer in high-head pumping station

Science.gov (United States)

Wang, L.; Wang, F. J.; Zou, Z. C.; Li, X. N.; Zhang, J. C.

2013-12-01

Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled.

Current experience and a new modeling on water hammer due to steam condensation in PWR secondary system

International Nuclear Information System (INIS)

Kawanishi, K.; Kasahara, J.; Ueno, T.; Suzuta, T.

1998-01-01

There have been possibilities to occur water hammer in pipelines of turbine system for nuclear or fossil fuel power plants. According to the NUREG report, approximately 150 events have been reported since 1969, we also have an experience recently. Water hammer occurs due to sudden steam condensation with pressure pulse. This kind of pressure pulses has been made by alternative producing and condensing of steam slug in the pipe and its frequency relates subcooling and pipe structures. This paper presents our current experience on water hammer with some experimental studies. The present experiment has been performed to obtain the data base for evaluating the pressure pulses. The test pipe was horizontal tubes with dead end connected to vertical tube which simulating drain line in PWR secondary system. The main results are shown as follows; Magnitude of pressure pulse depends drain velocity and initial subcooling. Pipe structure effects on the frequency and continual time of water hammer phenomenon. A new modeling for quantitative explanation of the phenomena is also presented

Muscle imbalance and reduced ankle joint motion in people with hammer toe deformity.

Science.gov (United States)

Kwon, O Y; Tuttle, L J; Johnson, J E; Mueller, M J

2009-10-01

Multiple factors may contribute to hammer toe deformity at the metatarsophalangeal joint. The purposes of this study were to (1) compare the ratio of toe extensor/flexor muscle strength in toes 2-4 among groups with and without hammer toe deformity, (2) to determine correlations between the ratio of toe extensor/flexor muscle strength in toes 2-4, and metatarsophalangeal joint deformity (3) to determine if other clinical measures differ between groups and if these measures are correlated with metatarsophalangeal joint angle. Twenty-seven feet with visible hammer toe deformity and 31 age matched feet without hammer toe deformity were tested. Toe muscle strength was measured using a dynamometer and the ratio of toe extensor muscle strength to flexor muscle strength was calculated. Metatarsophalangeal joint angle was measured from a computerized tomography image. Ankle and subtalar joint range of motion, and tibial torsion were measured using goniometry. Extensor/flexor toe muscle strength ratio was 2.3-3.0 times higher in the hammer toe group compared to the non-hammer toe group, in toes 2-4. The ratios of extensor/flexor toe muscle strength for toes 2-4 and metatarsophalangeal joint angle were highly correlated (r=0.69-0.80). Ankle dorsiflexion and metatarsophalangeal joint angle were negatively correlated for toes 2-4 (r=-0.38 to -0.56) as were eversion and metatarsophalangeal joint angle. These results provide insight into potential risk factors for the development of hammer toe deformity. Additional research is needed to determine the causal relationship between hammer toe deformity and the ratio of toe extensor/flexor muscle strength in toes 2-4.

Water hammer reduces fouling during natural water ultrafiltration.

Science.gov (United States)

Broens, F; Menne, D; Pothof, I; Blankert, B; Roesink, H D W; Futselaar, H; Lammertink, R G H; Wessling, M

2012-03-15

Today's ultrafiltration processes use permeate flow reversal to remove fouling deposits on the feed side of ultrafiltration membranes. We report an as effective method: the opening and rapid closing of a valve on the permeate side of an ultrafiltration module. The sudden valve closure generates pressure fluctuations due to fluid inertia and is commonly known as "water hammer". Surface water was filtrated in hollow fiber ultrafiltration membranes with a small (5%) crossflow. Filtration experiments above sustainable flux levels (>125 l (m2h)(-1)) show that a periodic closure of a valve on the permeate side improves filtration performance as a consequence of reduced fouling. It was shown that this effect depends on flux and actuation frequency of the valve. The time period that the valve was closed proved to have no effect on filtration performance. The pressure fluctuations generated by the sudden stop in fluid motion due to the valve closure are responsible for the effect of fouling reduction. High frequency recording of the dynamic pressure evolution shows water hammer related pressure fluctuations to occur in the order of 0.1 bar. The pressure fluctuations were higher at higher fluxes (higher velocities) which is in agreement with the theory. They were also more effective at higher fluxes with respect to fouling mitigation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Drilling comparison in "warm ice" and drill design comparison

DEFF Research Database (Denmark)

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

2007-01-01

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...... 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...

Ulnar hammer syndrome: a systematic review of the literature.

Science.gov (United States)

Vartija, Larisa; Cheung, Kevin; Kaur, Manraj; Coroneos, Christopher James; Thoma, Achilleas

2013-11-01

Ulnar hammer syndrome is an uncommon form of arterial insufficiency. Many treatments have been described, and debate continues about the best option. The goal of this systematic review was to determine whether ulnar hammer syndrome has an occupational association, to identify the most reliable diagnostic test, and to determine the best treatment modality. A comprehensive literature search was conducted using the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, MEDLINE, CINAHL, and EMBASE. Data from articles meeting inclusion criteria were collected in duplicate. Methodological quality of studies was assessed using the Methodological Index for Nonrandomized Studies scale. Thirty studies were included in the systematic review. No randomized controlled trials were identified. There is low-quality evidence suggestive of an association between exposure to repetitive hand trauma and vibration and ulnar hammer syndrome. Various diagnostic investigations were used, but few were compared, making it difficult to determine the most reliable diagnostic test. Numerous nonoperative and operative treatments were reported. With nonoperative treatment, 12 percent had complete resolution and 70 percent had partial resolution of their symptoms. Of patients treated operatively, 42.5 percent had complete resolution and 42.5 percent had partial resolution of their symptoms. The heterogeneity in study design and outcome measures limits definitive conclusions about occupational association, best diagnostic test, and treatment for ulnar hammer syndrome. However, there is low-quality evidence that suggests that most patients with ulnar hammer syndrome will have partial relief of symptoms with nonoperative treatment, and operative treatment results in complete or partial resolution of symptoms in the majority of cases. Therapeutic, IV.

Ex Vivo Evaluation of Cementless Acetabular Cup Stability Using Impact Analyses with a Hammer Instrumented with Strain Sensors.

Science.gov (United States)

Tijou, Antoine; Rosi, Giuseppe; Hernigou, Philippe; Flouzat-Lachaniette, Charles-Henri; Haïat, Guillaume

2017-12-27

The acetabular cup (AC) implant stability is determinant for the success of cementless hip arthroplasty. A method based on the analysis of the impact force applied during the press-fit insertion of the AC implant using a hammer instrumented with a force sensor was developed to assess the AC implant stability. The aim of the present study was to investigate the performance of a method using a hammer equipped with strain sensors to retrieve the AC implant stability. Different AC implants were inserted in five bovine samples with different stability conditions leading to 57 configurations. The AC implant was impacted 16 times by the two hammers consecutively. For each impact; an indicator I S (respectively I F ) determined by analyzing the time variation of the signal corresponding to the averaged strain (respectively force) obtained with the stress (respectively strain) hammer was calculated. The pull-out force F was measured for each configuration. F was significantly correlated with I S (R² = 0.79) and I F (R² = 0.80). The present method has the advantage of not modifying the shape of the hammer that can be sterilized easily. This study opens new paths towards the development of a decision support system to assess the AC implant stability.

On HammerCloud and ETF

CERN Document Server

Babik, Marian; CERN. Geneva. IT Department

2017-01-01

This technical report presents the two major synthetic testing platforms used in WLCG, HammerCloud (HC) and Experiments Test Framework (ETF). It gives an overview of their architecture, components, deployment and operations and discusses the possible commonalities/differences and possible future synergies between the two projects.

Experimental studies of water hammer in propellant feed system of reaction control system

Directory of Open Access Journals (Sweden)

Avanish Kumar

2018-03-01

Full Text Available Water hammer pressure transient produces large dynamic forces which can damage the pipes and other assemblies in the feed line of a reaction control system (RCS. It has led to the failure of pressure transducers monitoring the manifold pressure in the feed line of RCS. Therefore, water hammer studies have been carried out to understand its effect in feed line. Feedline system has been simplified to develop a mathematical model and experiments have been carried out at extensive levels. The mathematical model was developed considering pipe of uniform c/s and moving liquid-gas interface. The experimental studies have been done using water as working medium instead of actual propellant. The studies showed that rate of pressurization have a very critical role on the water hammer amplitude. Sensitivity studies have been also carried out to study the effect of density, friction and initial liquid column length on water hammer amplitude. Keywords: Water hammer, Reaction control system (RCS, Propellant feed system, Experimental study, Testing

Deep Drilling and Sampling via the Wireline Auto-Gopher Driven by Piezoelectric Percussive Actuator and EM Rotary Motor

Science.gov (United States)

Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart; Zacny, Kris; Paulsen, Gale L; Beegle, Luther; Bao, Xiaoqi

2012-01-01

The ability to penetrate subsurfaces and perform sample acquisition at depths of meters is critical for future NASA in-situ exploration missions to bodies in the solar system, including Mars and Europa. A corer/sampler was developed with the goal of acquiring pristine samples by reaching depths on Mars beyond the oxidized and sterilized zone. To developed rotary-hammering coring drill, called Auto-Gopher, employs a piezoelectric actuated percussive mechanism for breaking formations and an electric motor rotates the bit to remove the powdered cuttings. This sampler is a wireline mechanism that is incorporated with an inchworm mechanism allowing thru cyclic coring and core removal to reach great depths. The penetration rate is being optimized by simultaneously activating the percussive and rotary motions of the Auto-Gopher. The percussive mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that is driven by piezoelectric stack and that was demonstrated to require low axial preload. The Auto-Gopher has been produced taking into account the a lessons learned from the development of the Ultrasonic/Sonic Gopher that was designed as a percussive ice drill and was demonstrated in Antarctica in 2005 to reach about 2 meters deep. A field demonstration of the Auto-Gopher is currently being planned with objective of reaching as deep as 3 to 5 meters in tufa subsurface.

Water hammer calculation and analysis in main feedwater system of PWR nuclear power plants

International Nuclear Information System (INIS)

Wang Xin; Han Weishi

2010-01-01

The main feedwater system of a nuclear power plant is an important part in ensuring the cooling of the steam generator. Moreover, it is the main pipe section where water hammers frequently occur. Studying the regular patterns of water hammers to the main feedwater system is significant to the stable operation of the system. The paper focuses on the study of water hammers through Flowmaster's transient calculating function to establish a mathematical model with boundary conditions such as a feedwater pump, control valves, etc.; calculation of the water hammers pressure when feedwater pumps and control valves shut down; exporting the instantaneous change in solution of pressure. Combined with engineering practical examples, the conclusions verify the viability of calculating the water hammers pressure through Flowmaster's transient function, increasing the periods of closure of control valves and feedwater pumps control water hammers effectively, changing the intervals of closing signals to feedwater pumps and control valves to relieve hydraulic impact. This could be a guideline for practical engineering design and system optimization. (authors)

OREST, LWR Burnup Simulation Using Program HAMMER and ORIGEN

International Nuclear Information System (INIS)

Hesse, Ulrich; Sieberer, Johann

2006-01-01

1 - Description of program or function: In OREST, the 1-dimensional lattice code HAMMER and the isotope generation and depletion code ORIGEN are directly coupled for burnup simulation in light-water reactor fuels (GRS recommended). Additionally heavy water and graphite moderated systems can be calculated. New version differs from the previous version in the following features: An 84-group-library LIB84 for up to 200 isotopes is used to update the 3-group -POISON-XS. LIB84 uses the same energy boundaries as THERMOS and HAMLET in . In this way, high flexibility is achieved in very different reactor models. The coupling factor between THERMOS and HAMLET is now directly transferred from HAMMER to THERES and omits the equation 4 (see page 6 of the manual). Sandwich-reactor fuel reactivity and burnup calculations can be started with NGEOM = 1. Thorium graphite reactivity and burnup calculations can be started with NLIBE = 1. High enriched U-235 heavy water moderated reactivity and burnup calculations can be started. HAMLET libraries in for U-235, U-236, U-238, Np-237, Pu-238, Pu-239, Pu-240, Pu-242, Am-241, Am-243 and Zirconium are updated using resonance parameters. NEA-1324/04: A new version of the module hamme97.f has replaced the old one. 2 - Method of solution: For the user-defined irradiation history, an input data processor generates program loops over small burnup steps for the main codes HAMMER and ORIGEN. The user defined assembly description is transformed to an equivalent HAMMER fuel cell. HAMMER solves the integral neutron transport equation in a four-region cylindrical or sandwiched model with reflecting boundaries and runs with fuel power calculated rod temperatures. ORIGEN runs with HAMMER-calculated cross sections and neutron spectra and calculates isotope concentrations during burnup by solving the buildup-, depletion- and decay-chain equations. An output data processor samples the outputs of the program modules and generates tabular works for the

The significance of water hammer events to public dose from reactor accidents: A probabilistic assessment

International Nuclear Information System (INIS)

Amico, P.J.; Ferrell, W.L.; Rubin, M.P.

1984-01-01

A probabilistic assessment was made of the effects on public dose of water hammer events in LWRs. The analysis utilized actual historical water hammer data to determine if the water hammer events contributed either to system failure rates or initiating event frequencies. Representative PRAs were used to see if changes in initiating events and/or system failures caused by water hammer resulted in new values for the dominant sequences in the PRAs. New core melt frequencies were determined and carried out to the subsequent increase in public dose. It is concluded that water hammer is not a significant problem with respect to risk to the public for either BWRs or PWRs. (orig./HP)

Dynamic shock wave: hammer blow

International Nuclear Information System (INIS)

Lackme, Claude

1978-01-01

The general properties of shocks, their generation and the conditions of reflexion to an interface are dealt with in turn. By then applying these concepts to a liquid column and its environment (wall, free area, closing devices) the hammer blow is presented as being a relatively weak shock [fr

Water-hammer in the cold leg during an SBLOCA due to cold ECCS injection

International Nuclear Information System (INIS)

Ortiz, M.G.; Ghan, L.S.

1991-01-01

Water-hammer might occur in the cold leg of pressurized water reactors (PWR) during small break loss-of-coolant accidents (SBLOCA's), when cold emergency core cooling system (ECCS) water is injected into a pipe that may be partially filled with saturated steam. The water may mix with the steam and cause it to condense abruptly. Depending on the flow regime present, slugs of liquid may then be accelerated towards each other or against the piping structure. The possibility of this phenomenon is of concern to us because it may become a dominant phenomenon and change the character of the transient. In performing the code scaling, applicability, and uncertainty study (CSAU) on a SBLOCA scenario, we had to examine the possibility that the transient being analyzed could experience water-hammer and thus depart from the scope of the study. Two criteria for water-hammer initiation were investigated and tested using a RELAP5/MOD3 simulation of the transient. Our results indicated a very low likelihood of occurrence of the phenomenon. 8 refs., 6 figs

Hazardous Materials Management and Emergency Response (HAMMER)

Data.gov (United States)

Federal Laboratory Consortium — The Volpentest Hazardous Materials Management and Emergency Response (HAMMER) Federal Training Center is a safety and emergency response training center that offers...

Comparison of Piezosurgery and Hammer-Chisel in Endoscopic Dacryocystorhinostomy.

Science.gov (United States)

Çukurova, Ibrahim; Bulğurcu, Suphi; Arslan, Ilker Burak; Dikilitaş, Bünyamin

2018-05-08

In this study, we compared the advantages and disadvantages of piezosurgery and hammer-chisel used in endoscopic dacryocystorhinostomy (EDCR). Between January 2012 and January 2016, 10 women and 8 men in whom piezosurgery was used (group 1) and 11 women and 7 men in whom hammer-chisel was used (group 2) during EDCR operations were compared retrospectively. Recurrence, operation time, postoperative bleeding, and operative cost were evaluated in patients who were followed for an average of 11.8 months. In addition, visual analogue scale (VAS) was used to assess pain at 6 hours postoperatively. No recurrence was observed in group 1, but recurrence was observed in 2 patients in group 2 (P = 0.685). There was no postoperative bleeding in both groups. The mean duration of operation was 30.6 ± 8.2 minutes in group 1 and 46.8 ± 9.5 minutes in group 2 (P = 0.038). The VAS score in group 1 was 2.7 ± 1.4 and the VAS score in group 2 was 5.8 ± 2.2 (P = 0.01). Piezosurgery costs an additional $325 for each patient while the use of the hammer-chisel does not incur additional costs. Piezosurgery causes shorter operation time, less recurrence, and less pain when compared with hammer-chisel.

Uncertainty of Water-hammer Loads for Safety Related Systems

Energy Technology Data Exchange (ETDEWEB)

Lee, Seung Chan; Yoon, Duk Joo [Korea Hydro and Nuclear Power Co., LT., Daejeon (Korea, Republic of)

2013-10-15

In this study, the basic methodology is base on ISO GUM (Guide to the Expression of Uncertainty in Measurements). For a given gas void volumes in the discharge piping, the maximum pressure of water hammer is defined in equation. From equation, uncertainty parameter is selected as U{sub s} (superficial velocity for the specific pipe size and corresponding area) of equation. The main uncertainty parameter (U{sub s}) is estimated by measurement method and Monte Carlo simulation. Two methods are in good agreement with the extended uncertainty. Extended uncertainty of the measurement and Monte Carlo simulation is 1.30 and 1.34 respectively in 95% confidence interval. In 99% confidence interval, the uncertainties are 1.95 and 1.97 respectively. NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the possibility of noncondensable gas accumulation for the Emergency Core Cooling System. Specially, gas accumulation can result in system pressure transient in pump discharge piping at a pump start. Consequently, this evolves into a gas water, a water-hammer event and the force imbalances on the piping segments. In this paper, MCS (Monte Carlo Simulation) method is introduced in estimating the uncertainty of water hammer. The aim is to evaluate the uncertainty of the water hammer estimation results carried out by KHNP CRI in 2013.

FY1997 report on test well drilling and well investigation for the Akinomiya area survey in the geothermal development promotion survey; 1997 nendo chinetsu sokushin chosa. Akinomiya chiiki chosa shisui kussaku koji oyobi kosei chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

In order to extract promising areas with high geothermal feasibility, the Akinomiya area was surveyed by drilling test wells. In the N9-AY-3 excavating work, the first stage (depth from 15 to 33 m) used the water-free excavation to prevent adverse effects on the water sources. The second stage (depth from 33 to 409 m) reached the targeted depth with slanted excavation. The third stage drilled into depths from 409 to 1,006 m. The fourth stage was targeted to drill down to 1,802 m, but an entire lost returns have occurred at the depth of 1,598 m, whereas lost water drilling was performed by using fresh water, and the drilling was terminated at the targeted depth. The AY-4 excavation was also advanced with the first, second, third and fourth stage method, and when the entire lost returns have occurred at 1,196 m, the lost water drilling was carried out by using fresh water, and the drilling was terminated at the scheduled 1,505 m. The AY-5 excavation was also advanced with the first, second, third and fourth stage method. The first and second stages used water-free excavation (using air hammers) to avoid influence on the nearby spa areas. The third stage went down to 405 m performing coring, but the entire lost returns occurred at 298 m. The excavation rate was very high, and the core recovery rate reached 100%. The fourth stage presented the same coring condition as that for the third stage down to 1,002 m. (NEDO)

Slow drilling speeds for single-drill implant bed preparation. Experimental in vitro study.

Science.gov (United States)

Delgado-Ruiz, R A; Velasco Ortega, E; Romanos, G E; Gerhke, S; Newen, I; Calvo-Guirado, J L

2018-01-01

To evaluate the real-time bone temperature changes during the preparation of the implant bed with a single-drill protocol with different drill designs and different slow drilling speeds in artificial type IV bone. For this experimental in vitro study, 600 implant bed preparations were performed in 10 bovine bone disks using three test slow drilling speeds (50/150/300 rpm) and a control drilling speed (1200 rpm). The temperature at crestal and apical areas and time variations produced during drilling with three different drill designs with similar diameter and length but different geometry were recorded with real-life thermographic analysis. Statistical analysis was performed by two-way analysis of variance. Multiple comparisons of temperatures and time with the different drill designs and speeds were performed with the Tukey's test. T Max values for the control drilling speed with all the drill designs (D1 + 1200; D2 + 1200; D3 + 1200) were higher compared to those for the controls for 11 ± 1.32 °C (p drilling at 50 rpm resulted in the lowest temperature increment (22.11 ± 0.8 °C) compared to the other slow drilling speeds of 150 (24.752 ± 1.1 °C) and 300 rpm (25.977 ± 1.2 °C) (p drilling speeds compared to that for the control drilling speed. Slow drilling speeds required significantly more time to finish the preparation of the implant bed shown as follows: 50 rpm > 150 rpm > 300 rpm > control (p drill protocol with slow drilling speeds (50, 150, and 300 rpm) without irrigation in type IV bone increases the temperature at the coronal and apical levels but is below the critical threshold of 47 °C. The drill design in single-drill protocols using slow speeds (50, 150, and 300 rpm) does not have an influence on the thermal variations. The time to accomplish the implant bed preparation with a single-drill protocol in type IV bone is influenced by the drilling speed and not by the drill design. As the speed decreases, then

Experimental Study on the Measurement of Water Bottom Vibration Induced by Underwater Drilling Blasting

Directory of Open Access Journals (Sweden)

Gu Wenbin

2015-01-01

Full Text Available Due to the lack of proper instrumentations and the difficulties in underwater measurements, the studies about water bottom vibration induced by underwater drilling blasting are seldom reported. In order to investigate the propagation and attenuation laws of blasting induced water bottom vibration, a water bottom vibration monitor was developed with consideration of the difficulties in underwater measurements. By means of this equipment, the actual water bottom vibration induced by underwater drilling blasting was measured in a field experiment. It shows that the water bottom vibration monitor could collect vibration signals quite effectively in underwater environments. The followed signal analysis shows that the characteristics of water bottom vibration and land ground vibration induced by the same underwater drilling blasting are quite different due to the different geological environments. The amplitude and frequency band of water bottom vibration both exceed those of land ground vibration. Water bottom vibration is mainly in low-frequency band that induced by blasting impact directly acts on rock. Besides the low-frequency component, land vibration contains another higher frequency band component that induced by followed water hammer wave acts on bank slope.

A study of water hammer phenomena in a one-component two-phase bubbly flow

International Nuclear Information System (INIS)

Fujii, Terushige; Akagawa, Koji

2000-01-01

Water hammer phenomena caused by a rapid valve closure, that is, shock phenomena in two-phase flows, are an important problem for the safety assessment of a hypothetical LOCA. This paper presents the results of experimental and analytical studies of the water hammer phenomena in a one-component tow-phase bubbly flow. In order to clarify the characteristics of water hammer phenomena, experiments for a one-component two-phase flow of Freon R-113 were conducted and a numerical simulation of pressure transients was developed. An overall picture of the water hammer phenomena in a one-component two-phase flow is presented an discussed. (author)

Water hammer due to rapid bubble growth at a severe accident

International Nuclear Information System (INIS)

Aya, Izuo; Adachi, Masaki; Shiozaki, Koki; Inasaka, Fujio

2000-01-01

On a severe accident of the light water reactor (LWR), by steam explosion and so forth due to hydrogen formation by water-metal reaction and direct contact of molted core with water, it is presumed that a lot of vapor forms for a short time in water at reactor vessel and under part of containment vessel. This study aims at and carries out, under reference of the conventional study results, experimental elucidation on coherence of water block motion due to rapid bubble growth, proposal on reduction method of water hammering, development of water hammer estimating method in an actual reactor, and proposal for upgrading of reliability on severe accident evaluation. In 1998 fiscal year, an 'Experimental apparatus on water hammering elements on sever accident' simulated rapid bubble growth due to steam explosion by injecting high pressure air into water was produced to carry out its function test. As a result of the carried out function tests, extreme water hammering phenomena were observed, by which validity of establishment on the study objects could be confirmed. (G.K.)

STUDY ON OPERATING CHARACTERISTECS OF WATER HAMMER GENERATING DEVICE FOR TREATMENT OF MICROORGANISM

Science.gov (United States)

Hamada, Tatsuhisa; Endo, Shigekatsu; Oda, Akira; Shimizu, Yasushi

The phenomenon that has been actualized due to the water quality deterioration because of the inflow of drainage and the industrial wastewater includes the phenomenon that is called water-bloom generated in the freshwater environment made a eutrophic. This is becoming a serious problem to secure the water.Mixing with the drinking water has already been confirmed, and the generation of water-bloom is becoming a big social problem, and fundamental measures have not been established yet.On the other hand, authors are proving the pressure to be a fast the pressure speed of the impact pressure by the water hammer and effective in the destruction of the blue-green algae.In this studies, the hydraulics flow characteristics of an effective water hammer pressure generator to the shredding of the water-bloom cell were examined.As a result, there was a boundary in the region where the water hammer was generated by length and the water supply head of conduit, and the water hammer pressure was able to be understood to be influenced according to the angle of the valve that generated the water hammer in addition in the water hammer generator.The demonstration in the locale was confirmed based on these and the scale etc. of an effective device to the doing water-bloom processing were able to be confirmed by continuous running.

Correlation between rotary drill performance parameters and borehole geophysical logging

International Nuclear Information System (INIS)

Scoble, M.J.; Peck, J.; Hendricks, C.

1989-01-01

There is a growing interest in developing performance monitoring techniques for both surface and underground mining equipment used in excavating, loading and transport systems. Research into the techniques and applications for monitoring drilling machinery including gamma and neutron logging, is reviewed. 17 refs.; 5 figs

Effects of valve characteristics and pipe diameter on water hammer phenomena

International Nuclear Information System (INIS)

Hur, J.; Kim, T. H.; Mun, B. H.; Choi, H. Y.; Lee, K. W.; Noh, T. S.

2001-01-01

The water hammer phenomena mean that the dynamic loads are induced on the pipe, the pipe support and the equipments in the system due to the sudden change of the flow velocity inside the pipe. The sudden changes are mainly caused by the valve sudden on/off and pump sudden start/trip. To develop a selection criterion of the parts to be analyzed for the water hammer, the effects of the valve characteristics and pipe diameter on the water hammer are analyzed. The analyses using Method of Characteristics (MOC) show that the effects of the valve pressure difference and the valve opening time are very significant, but the effects of the pipe diameter are not dominant

Application of odex drilling method in a variably fractured volcanic/igneous environment

International Nuclear Information System (INIS)

Murphy, J.

1992-01-01

A case history of a subsurface investigation at a geothermal waste disposal facility within a volcanic flow regime illustrates a classic example of critical drilling problems arising from severe air and mud circulation loss. Extremely dense dacite and rhyolite rock alternating with severely fractured flow margins (interconnected with numerous voids and caverns) has provided the scenario for open-quotes gravel pilesclose quotes of substantial size between competent dacite flows. The interconnected void space at numerous depths beneath the site is great enough to create complete loss of circulation while using more than 3000 cubic feet per minute (cfm) of air at 350 pounds per square inch (psi). This initial failed effort also included the use of a foam additive. The technologies employed at this site to address the problem of circulation loss included air rotary casing hammer methods, mud rotary (with beat pulp additives and linen additives), boring wall stabilization, telescoped casing and ultimately the ODEX casing advancement system. The relative success of this seldom used method invites a discussion of the principals of the under-reamer drilling method (ODEX) and the physical limitations of the system. A practical knowledge of the advantages and disadvantages of each drilling method is necessary when designing an investigation addressing problems of soil and water contamination. Additionally, by addressing the methods that were unsuccessful, geologists, contractors and engineers can gain insight into the value and application of the various technologies available for similar drilling problems

Method to study water hammer with fluid-structure interaction in spatial pipe

International Nuclear Information System (INIS)

Xi Zhide; Ma Jianzhong; Sun Lei

2013-01-01

The theory of coupling 4-function models and its solution approach are first introduced in this paper, and the method of CFD to calculate fluid-structure interaction is also introduced. Finally, the model in related reference is applied with this method to simulate the process of water hammer. By CFD calculation for the classical water hammer, the numerical scheme and grid are selected, and the results of CFD are compared with reference. The results show that the method in this paper can be used in more complex pipe system to simulate the water hammer effect. (authors)

Mathematical Methodology for New Modeling of Water Hammer in Emergency Core Cooling System

International Nuclear Information System (INIS)

Lee, Seungchan; Yoon, Dukjoo; Ha, Sangjun

2013-01-01

In engineering insight, the water hammer study has carried out through the experimental work and the fluid mechanics. In this study, a new access methodology is introduced by Newton mechanics and a mathematical method. Also, NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the effect of water-hammer for the protection of pipes of the Emergency Core Cooling System, which is related to the Residual Heat Removal System and the Containment Spray System. This paper includes modeling, the processes of derivation of the mathematical equations and the comparison with other experimental work. To analyze the effect of water-hammer, this mathematical methodology is carried out. This study is in good agreement with other experiment results as above. This method is very efficient to explain the water-hammer phenomena

Mathematical Methodology for New Modeling of Water Hammer in Emergency Core Cooling System

Energy Technology Data Exchange (ETDEWEB)

Lee, Seungchan; Yoon, Dukjoo; Ha, Sangjun [Korea Hydro Nuclear Power Co. Ltd, Daejeon (Korea, Republic of)

2013-05-15

In engineering insight, the water hammer study has carried out through the experimental work and the fluid mechanics. In this study, a new access methodology is introduced by Newton mechanics and a mathematical method. Also, NRC Generic Letter 2008-01 requires nuclear power plant operators to evaluate the effect of water-hammer for the protection of pipes of the Emergency Core Cooling System, which is related to the Residual Heat Removal System and the Containment Spray System. This paper includes modeling, the processes of derivation of the mathematical equations and the comparison with other experimental work. To analyze the effect of water-hammer, this mathematical methodology is carried out. This study is in good agreement with other experiment results as above. This method is very efficient to explain the water-hammer phenomena.

Reliability of the input admittance of bowed-string instruments measured by the hammer method.

Science.gov (United States)

Zhang, Ailin; Woodhouse, Jim

2014-12-01

The input admittance at the bridge, measured by hammer testing, is often regarded as the most useful and convenient measurement of the vibrational behavior of a bowed string instrument. However, this method has been questioned, due especially to differences between human bowing and hammer impact. The goal of the research presented here is to investigate the reliability and accuracy of this classic hammer method. Experimental studies were carried out on cellos, with three different driving conditions and three different boundary conditions. Results suggest that there is nothing fundamentally different about the hammer method, compared to other kinds of excitation. The third series of experiments offers an opportunity to explore the difference between the input admittance measuring from one bridge corner to another and that of single strings. The classic measurement is found to give a reasonable approximation to that of all four strings. Some possible differences between the hammer method and normal bowing and implications of the acoustical results are also discussed.

A Long-Term Performance Enhancement Method for FOG-Based Measurement While Drilling.

Science.gov (United States)

Zhang, Chunxi; Lin, Tie

2016-07-28

In the oil industry, the measurement-while-drilling (MWD) systems are usually used to provide the real-time position and orientation of the bottom hole assembly (BHA) during drilling. However, the present MWD systems based on magnetic surveying technology can barely ensure good performance because of magnetic interference phenomena. In this paper, a MWD surveying system based on a fiber optic gyroscope (FOG) was developed to replace the magnetic surveying system. To accommodate the size of the downhole drilling conditions, a new design method is adopted. In order to realize long-term and high position precision and orientation surveying, an integrated surveying algorithm is proposed based on inertial navigation system (INS) and drilling features. In addition, the FOG-based MWD error model is built and the drilling features are analyzed. The state-space system model and the observation updates model of the Kalman filter are built. To validate the availability and utility of the algorithm, the semi-physical simulation is conducted under laboratory conditions. The results comparison with the traditional algorithms show that the errors were suppressed and the measurement precision of the proposed algorithm is better than the traditional ones. In addition, the proposed method uses a lot less time than the zero velocity update (ZUPT) method.

Performance of engine-driven rotary endodontic instruments with a superimposed bending deflection: V. Gates Glidden and Peeso drills.

Science.gov (United States)

Brantley, W A; Luebke, N H; Luebke, F L; Mitchell, J C

1994-05-01

A laboratory study was performed on Gates Glidden and Peeso drills to determine the incidence of shaft fracture when a bending deflection was superimposed on the rotating drills. Samples of sizes #1 to #6 stainless steel Gates Glidden drills, sizes #1 to #6 stainless steel and carbon steel-type P Peeso drills, and sizes #009 to #023 carbon steel-type B-1 Peeso drills from each of two manufacturers were evaluated with a unique apparatus that applied a 2-mm bending deflection while rotating the instruments. The apparatus did not restrict movement of the bur head during rotation. The test drills were rotated at 2500, 4000, and 7000 revolutions per minute, and the number of revolutions at failure was recorded. Scanning electron microscopic observations established that the stainless steel Gates Glidden and Peeso drills failed by ductile fracture, whereas the carbon steel Peeso drills failed by brittle fracture. Instrument fracture was always near the handpiece shank with this test, and the length of the fractured drills was measured from the working tip. It is recommended that this additional test be adopted to determine fatigue properties of engine-driven rotary endodontic instruments in establishing international performance standards.

Factors analysis of water hammer in FLOWMASTER for main feedwater systems of PWR nuclear power plants

International Nuclear Information System (INIS)

Wang Xin; Han Weishi

2010-01-01

The main feedwater system of a nuclear power plant (NPP) is an important part in ensuring the cooling of a steam generator. It is the main pipe section where water hammers frequently occur. Studying the regulator patterns of water hammers in the main feedwater systems is significant to the stable operation of the system. This article focuses on a parametric study to avoid the consequences of water hammer effect in PWR by employing a general purpose fluid dynamic simulation software-FLOWMASTER. Through FLOWMASTER's transient calculating functions, a mathematical model is established with boundary conditions such as feedwater pumps, control valves, etc., calculations of water hammer pressure when feedwater pumps and control valves shut down, and simulations during instantaneous changes in water hammer pressure. Combining a plethora of engineering practical examples, this research verified the viability of calculating water hammer pressure through FLOWMASTER's transient functions and we found out that, increasing the periods of closure of control valves and feedwater pumps control water hammers effectively. We also found out that changing the intervals of closing signals to feedwater pumps and control valves aid to relieve hydraulic impact. This could be a guideline for practical engineering design and system optimization. (author)

Optimal Control of the Valve Based on Traveling Wave Method in the Water Hammer Process

Science.gov (United States)

Cao, H. Z.; Wang, F.; Feng, J. L.; Tan, H. P.

2011-09-01

Valve regulation is an effective method for process control during the water hammer. The principle of d'Alembert traveling wave theory was used in this paper to construct the exact analytical solution of the water hammer, and the optimal speed law of the valve that can reduce the water hammer pressure in the maximum extent was obtained. Combining this law with the valve characteristic curve, the principle corresponding to the valve opening changing with time was obtained, which can be used to guide the process of valve closing and to reduce the water hammer pressure in the maximum extent.

Well successfully drilled with high performance water-based fluid: Santos Basins, offshore Brazil

Energy Technology Data Exchange (ETDEWEB)

Fornasier, Frank C.; Luzardo, Juan P. [Halliburton Company, Houston, TX (United States); Bishnoi, M.L. [Oil and Natural Gas Corporation Ltda. (ONGC), Dehradun (India)

2012-07-01

Santos Basin is a 352,260 square kilometers (136,010 sq mi) offshore pre-salt basin. It is located in the South Atlantic Ocean, some 300 kilometers (190 mi) South East of Sao Paulo, Brazil. One of the largest Brazilian sedimentary basins, it is the site of several recent significant oil fields, including Tupi and Jupiter. The criteria for drilling fluid selection is based upon the following factors: maximum cost efficiency, environmental friendliness, optimum borehole stability, and ease of use. The recommended drilling fluid formulation takes into consideration the experience gained during the drilling of wells in the Santos Basin area. The operator wanted to use a high-performance water-based fluid (HPWBF) that could provide shale inhibition, wellbore stability, lubricity and improved rate of penetration (ROP) as an alternative to synthetic-based drilling fluids to present value in terms of economics and environmental friendliness. The HPWBF consists of three synergistic products: a hydration suppressant, a dispersion suppressant, and an accretion suppressant. The system is formulated based on customized solutions for managing the clay reactivity. High logistics costs require drilling fluids that can be prepared with sea water and discharged to the sea without environmental impact. The HPWBF is a clay-free system designed for maximum shale inhibition in highly reactive formations. The system can provide wellbore stability, high rates of penetration, and acceptable rheological properties over a wide range of temperatures, with the added benefit of allowing cuttings discharge based upon water base environmental restrictions. Since no oil is used in the formulation, the HPWBF eliminates the need for cuttings processing and monitoring equipment, and exceeds the environmental requirements by achieving an LC50 value of 345,478.22 ppm in comparison with the minimum requirement (LC50 > 30,000 ppm in 96 hr), permitting use and discharge to the sea. The HPWBF selected

Anisotropy in Alpedrete granite cutting (Rift, Grain and Hardway directions) and effect on bush hammered heritage ashlars

Science.gov (United States)

Freire-Lista, David Martin; Fort, Rafael

2015-04-01

Many monuments and cities that are part of humanity's heritage have been built with carved granite ashlars. This dimension stone is one of the most used due to its abundance and durability. Traditional quarrymen have used anisotropic planes to cut granite blocks in the quarry for improved cutting performance. These planes are called Rift, Grain and Hardway (R, G, H) according to the ease of cutting. The aim of this study is to determine the response of each of the three orthogonal cutting planes R, G and H to the craft styling with bush hammer, based on their decay. Alpedrete granite was selected for this research, it is a monzogranite quarried in the Sierra de Guadarrana (Spanish Central System) foothills, in the province of Madrid, Spain. It is one of the most representative of Madrid's heritage granites. Alpedrete granite is also used as building stone in other European cities. From an Alpedrete granite bush hammered ashlar, three thin sections were cut parallel to the H plane; these thin sections cut R and G bush hammered planes. Also three thin sections have been cut parallel to the R plane at a distance of 2 mm, 10 mm and 30 mm from the bush hammered surface. All thin sections have been treated with fluorescein. In each of the thin sections a micrograph mosaic was performed covering the entire area (about 10 cm2, 300 photomicrographs) and printed with 120 increases. The length and spacing of inter-, intra- and trans-crystalline microcracks were quantified and measured. Microcracks were subdivided based on affected minerals in each R, G and H planes. Through these observations it was found that Alpedrete Granite R plane (easier to cut) is determined by exfoliation microcracks orientation. That is, R plane is parallel to the exfoliations microcracks, which are intra-crystalline and straight. The cutting of stones in the R plane is due to the coalescence of straight microcracks in the plane. This plane minimizes the effort and cost of subsequent carving so it

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

Energy Technology Data Exchange (ETDEWEB)

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)

2004-07-01

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)

Prevention and mitigation of steam-generator water-hammer events in PWR plants

International Nuclear Information System (INIS)

Han, J.T.; Anderson, N.

1982-11-01

Water hammer in nuclear power plants is an unresolved safety issue under study at the NRC (USI A-1). One of the identified safety concerns is steam generator water hammer (SGWH) in pressurized-water reactor (PWR) plants. This report presents a summary of: (1) the causes of SGWH; (2) various fixes employed to prevent or mitigate SGWH; and (3) the nature and status of modifications that have been made at each operating PWR plant. The NRC staff considers that the issue of SGWH in top feedring designs has been technically resolved. This report does not address technical findings relevant to water hammer in preheat type steam generators. 10 figures, 2 tables

The impacts of hammer-mill screen size and grain particle size on the performance of broiler chickens offered diets based on two red sorghum varieties.

Science.gov (United States)

Selle, P H; Truong, H H; Khoddami, A; Moss, A F; Roberts, T H; Liu, S Y

2016-12-12

1. The two red grain sorghums were extensively characterised. Kafirin, polyphenolic compounds, free, conjugated and bound phenolic acids, phytate concentrations and starch pasting profiles were determined. 2. The experiment consisted of a 2 × 4 factorial array of dietary treatments comprising two red sorghum varieties (Tiger and Block I) ground through 4 hammer-mill screen sizes (2.0, 3.2, 4.8 6.0 mm) prior to incorporation into nutritionally equivalent diets. Eight steam-pelleted dietary treatments were each offered to 7 replicates (6 male Ross 308 birds per cage) from 7 to 28 d post-hatch. 3. Effects of dietary treatments on growth performance, relative gizzard and pancreas weights, nutrient utilisation, apparent starch and protein (N) digestibility coefficients and disappearance rates from 4 small intestinal segments were determined. 4. The 2.0-mm hammer-mill screen generated an average geometric mean particle size of 794 μm and the 6.0-mm screen a mean particle size of 1405 μm. However, hammer-mill screen size did not influence weight gain or FCR. The 6.0-mm screen size generated significantly higher starch and protein (N) digestibility coefficients in the distal jejunum and distal ileum than the 2.0-mm hammer-mill screen. 5. Tiger sorghum was superior to Block I sorghum, as significant advantages were observed for feed conversion ratios (3.25%), AME (0.37 MJ), ME:GE ratios (4.15%), AMEn (0.53 MJ), distal ileal starch digestibility coefficients (2.46%) and protein (N) digestibility coefficients in the distal jejunum (4.66%), proximal ileum (1.96%) and distal ileum (2.16%). The inferior Block I sorghum contained more kafirin (67.1 versus 51.3 g/kg), phytate (9.79 versus 8.40 g/kg), total phenolic compounds (4.68 versus 4.12 mg GAE/g), flavan-4-ols (7.98 versus 5.04 ABS/ml/g), total phenolic acids (554 versus 402 μg/g) and total ferulic acid (375 versus 281 μg/g) in comparison to Tiger sorghum.

Sketches of a hammer-impact, spiked-base, shear-wave source

Science.gov (United States)

Hasbrouck, W.P.

1983-01-01

Generation of shear waves in shallow seismic investigations (those to depths usually less than 100 m) can be accomplished by horizontally striking with a hammer either the end of a wood plank or metal structure embedded at the ground surface. The dimensioned sketches of this report are of a steel, hammer-impact, spiked-base, shear-wave source. It has been used on outcrops and in a desert environment and for conducting experiments on the effect of rotating source direction.

An analysis on water hammer in liquid injection shutdown system of CANDU-9

International Nuclear Information System (INIS)

Kim, T. H.; Heo, J.; Han, S. K.; Choi, H. Y.; No, T. S.

2000-01-01

The water hammer analysis code, PTRAN, is used for computation of transient pressures and pressure differentials in the Liquid Injection Shutdown System(LISS) piping network of CANDU-9 to ensure that the design allowables for LEVEL C Service Limit are met for the water hammer loads resulting from the water hammer. The LISS piping network of CANDU-9 has incorporated design improvement in considering the water hammer, such as declining the horizontal part of helium header, and raising the elevation of the overall system piping configuration, etc. The maximum pressure in the LISS piping network is found to be 7.92 MPa(a) at the closed valve in the vent line, which is below the allowable working pressure and the valve design pressure under Level C service conditions. And it is also shown that the maximum pressure in CANDU-9 is much lower than that in CANDU-6

Moving HammerCloud to CERN's private cloud

CERN Document Server

Barrand, Quentin

2013-01-01

HammerCloud is a testing framework for the Worldwide LHC Computing Grid. Currently deployed on about 20 hand-managed machines, it was desirable to move it to the Agile Infrastructure, CERN's OpenStack-based private cloud.

Modelling of Cold Water Hammer with WAHA code

International Nuclear Information System (INIS)

Gale, J.; Tiselj, I.

2003-01-01

The Cold Water Hammer experiment described in the present paper is a simple facility where overpressure accelerates a column of liquid water into the steam bubble at the closed vertical end of the pipe. Severe water hammer with high pressure peak occurs when the vapor bubble condenses and the liquid column hits the closed end of the pipe. Experimental data of Forschungszentrum Rossendorf are being used to test the newly developed computer code WAHA and the computer code RELAP5. Results show that a small amount of noncondensable air in the steam bubble significantly affects the magnitude of the calculated pressure peak, while the wall friction and condensation rate only slightly affect the simulated phenomena. (author)

1D models for condensation induced water hammer in pipelines

International Nuclear Information System (INIS)

Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas

2013-01-01

Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

1D models for condensation induced water hammer in pipelines

Energy Technology Data Exchange (ETDEWEB)

Bloemeling, Frank; Neuhas, Thorsten; Schaffrath, Andreas [TUEV NORD SysTec GmbH und Co. KG, Hamburg (Germany)

2013-03-15

Condensation induced water hammer (CIWH) are caused by contact of steam and subcooled water. Thus, modeling the direct contact condensation is a crucial step towards the simulation of condensation induced water hammer with 1D pressure surge codes. Therefore, also the TUeV NORD SysTec GmbH and Co. KG inhouse pressure surge code DYVRO has been equipped with a new contact condensation model. The validation of DYVRO against an experiment dealing with CIWH is presented in this contribution. (orig.)

Physics-Based Pneumatic Hammer Instability Model, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Florida Turbine Technologies (FTT) proposes to conduct research necessary to develop a physics-based pneumatic hammer instability model for hydrostatic bearings...

Effects of a Short Drilling Implant Protocol on Osteotomy Site Temperature and Drill Torque.

Science.gov (United States)

Mihali, Sorin G; Canjau, Silvana; Cernescu, Anghel; Bortun, Cristina M; Wang, Hom-Lay; Bratu, Emanuel

2018-02-01

To establish a protocol for reducing the drilling sequence during implant site preparation based on temperature and insertion torque. The traditional conventional drilling sequence (used several drills with 0.6-mm increment each time) was compared with the proposed short drilling protocol (only used 2 drills: initial and final drill). One hundred drilling osteotomies were performed in bovine and porcine bones. Sets of 2 osteotomy sites were created in 5 bone densities using 2 types of drilling protocols. Thermographic pictures were captured throughout all drilling procedures and analyzed using ThermaCAM Researcher Professional 2.10. Torque values were determined during drilling by measuring electrical input and drill speed. There were statistically significant differences in bone temperature between the conventional and short drilling protocols during implant site preparation (analysis of variance P = 0.0008). However, there were no significant differences between the 2 types of drilling protocols for both implant diameters. Implant site preparation time was significantly reduced when using the short drilling protocol compared with the conventional drilling protocol (P drilling protocol proposed herein may represent a safe approach for implant site preparation.

Management of Hypothenar Hammer Syndrome A Case Report.

Science.gov (United States)

Swofford, Brenen P; Swofford, Devon P

2018-02-09

BACKGROUND Hypothenar hammer syndrome is a relatively rare disease process caused by repetitive stress or injury to the hypothenar eminence leading to chronic injury to the ulnar artery. This chronic stress (usually as a result of occupational or sport activities) may result in arterial constriction or thickening, which may lead to thrombosis or aneurysm formation. A review of current literature revealed that reports related to management of hypothenar hammer syndrome are limited. CASE REPORT A 33-year-old male without significant past medical history presented with left hand/digit pain, skin discoloration, and coolness of the hand/digits after a mechanical accident experienced 12 hours prior to presentation. Angiography confirmed reduced flow in the ulnar and radial artery with significant spasm of the ulnar artery. Treatment consisted of heparin, nitroglycerin, and papaverine with rapid resolution of symptoms. The patient was discharged on anticoagulation and a calcium channel blocker, with scheduled follow-up. CONCLUSIONS Hypothenar hammer syndrome is a rare disease process which manifests in certain occupations and activities that put undue stress on the hypothenar area. The use of angiography for definitive diagnosis and the use of anticoagulation and calcium channel blockers for treatment should continue to be studied to determine a standard treatment regimen.

Physics-Based Pneumatic Hammer Instability Model, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The objective of this project is to develop a physics-based pneumatic hammer instability model that accurately predicts the stability of hydrostatic bearings...

New high-performance, water-based fluid benefits Santos basin operations with excellent inhibition and drilling efficiency

Energy Technology Data Exchange (ETDEWEB)

Anderson, Tom; West, Gary [Halliburton Baroid, Santos, SP (Brazil)

2004-07-01

For decades drilling fluids companies have been striving to create a water-based fluid (WBF) that yields performance similar to that of an invert emulsion in the areas of hole stability, rate of penetration (ROP) and lubricity. The HYDRO-GUARD system is a new highly inhibitive WBF that can yield drilling performance approaching that of an invert emulsion system. The new system uses a new combination of polymeric additives designed to inhibit reactive clays, minimize colloidal solids buildup, and produce a lubricious, gauge wellbore. This paper compares the field performance of the HYDRO-GUARD system on two recent Santos Basin wells drilled to over 5,000 m with the performance of synthetic-based fluids (SBF) used historically in the same area. Bottom hole temperatures (BHT) on these wells exceeded 315 deg F (157 deg C). Performance measures such as hole cleaning, penetration rates, hole stability, and torque and drag will be reviewed as well as general system benefits. (author)

Analisa Pengaruh Water Hammer Terhadap Nilai Strees Pipa Pada Sistem Loading-Offloading PT.DABN

Directory of Open Access Journals (Sweden)

Tri Adi Siswanto

2014-03-01

Full Text Available Jalur pipa (pipeline merupakan media yang  digunakan sebagai alat transportasi fluida (cair atau gas, mixed of liquid, solid dan fluid-solid mixture. Ada beberapa tahap penting dalam siklus suatu jalur perpipaan yang digunakan sebagai alat transportasi minyak atau gas: desain, konstruksi, operasional dan pemeliharaan, dan terakhir perbaikan. Operasional merupakn proses kemungkinan terbesar terjadinya kegagalan pada suatu jalur perpipaan. Salah satu kegagalan yang mungkin terjadi adalah fenomena water hammaer. Water hammer adalah sebuah fenomena terjadinhya kenaiakan tekanan yang disebabkan oleh terhenti atau dihentikannya aliran di dalam pipa secara mendadak. Hal ini bisa disebabkan oleh operasional penutupan katup yang dilakukan secara tiba-tiba. Pada paper ini akan dijelaskan kajian mengenai pengaruh kenaikan tekanan yang terjadi karena adanya fenomena water hammer terhadap nilai tegangan jalur perpipaan di sisi discharge. Dari hasil perhitungan diketahui bahwa kenaikan tekanan akibat fenomena water hammer sangat mempengaruhi naiknya nilai tegangan pada pipa. Hasil analisa menunjukan bahwa tegangan yang terjadi ketika fenomena water hammer masih dapat diterima, tetapi kenaikan tekanan ketika terjadi fenomena water hammer melebihi dari batas yang diizinkan sehingga perlu dilakukan prosedur penutupan katup yang sesuai untuk menjaga agar pada saat dioperasionalkan pipa dalam kondisi aman.

Water hammer analysis in a water distribution system

Directory of Open Access Journals (Sweden)

John Twyman

2017-04-01

Full Text Available The solution to water hammer in a water distribution system (WDS is shown by applying three hybrid methods (HM based on the Box’s scheme, McCormack's method and Diffusive Scheme. Each HM formulation in conjunction with their relative advantages and disadvantages are reviewed. The analyzed WDS has pipes with different lengths, diameters and wave speeds, being the Courant number different in each pipe according to the adopted discretization. The HM results are compared with the results obtained by the Method of Characteristics (MOC. In reviewing the numerical attenuation, second order schemes based on Box and McCormack are more conservative from a numerical point of view, being recommendable their application in the analysis of water hammer in water distribution systems.

Technical performance of drilling operations of wells Erslev 1 and 2 on Mors Salt Dome

International Nuclear Information System (INIS)

Gomm, H.

1982-01-01

This paper deals strictly with the performance of the drilling itself. The wells were designed and drilled by an international team of experts, using a Cabot Franks Explorer 900 rig. The two exploration wells were located in the top area of the Mors Saltdome after geological and geophysical investigations at a distance of about 1 100 m. (EG)

The effect of cryogenic grinding and hammer milling on the flavour quality of ground pepper (Piper nigrum L.).

Science.gov (United States)

Liu, Hong; Zeng, Fankui; Wang, Qinghuang; Ou, Shiyi; Tan, Lehe; Gu, Fenglin

2013-12-15

In this study, we compared the effects of cryogenic grinding and hammer milling on the flavour attributes of black, white, and green pepper. The flavour attributes were analysed using headspace solid-phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC/MS), sensory evaluation and electronic nose (e-nose) analysis. Cryogenic grinding resulted in minimal damage to the colour, flavour, and sensory attributes of the spices. Cryogenic grinding was also better than hammer milling at preserving the main potent aroma constituents, but the concentrations of the main aroma constituents were dramatically reduced after storing the samples at 4 °C for 6 months. Pattern matching performed by the e-nose further supported our sensory and instrumental findings. Overall, cryogenic grinding was superior to hammer milling for preserving the sensory properties and flavour attributes of pepper without significantly affecting its quality. However, we found that the flavour quality of ground pepper was reduced during storage. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sensitivity and specificity of bell-hammer tear as an indirect sign of partial anterior cruciate ligament rupture on magnetic resonance imaging.

Science.gov (United States)

Lefevre, N; Naouri, J F; Bohu, Y; Klouche, S; Herman, S

2014-05-01

The main purpose of this study was to evaluate the usefulness of the bell-hammer sign in the diagnosis of partial tears of the anterior cruciate ligament (ACL) of the knee on MRI. A retrospective study was performed including all patients who underwent ACL reconstruction for partial or complete tears from 2008 to 2009. The diagnosis of partial or complete ACL tears was based on the appearance of the ligament bundles and the signal quality on MRI. On arthroscopy, which is considered the gold standard, each bundle was classified as normal, partially or completely torn depending on the extent of the rupture and the quality of the remaining fibres. The study included 312 patients, 83 women and 229 men (mean age 33.3 ± 19.6 years). A diagnosis of a tear was made in all patients on preoperative MRI. Arthroscopy did not show any normal ACL, 247/312 (79.2 %) complete tears and 65/312 (20.8%) partial tears, 50/65 (76.9%) on the anteromedial bundle (AM) and 15/65 (23.1%) the posterolateral bundle. The bell-hammer sign was found on MRI in 13/312 patients (4.5%). It involved 9/65 (13.8%) partial tears, all in the AM bundle, and 4/247 (1.6%) complete tears, significantly more frequent in cases of partial rupture (p hammer sign (sensitivity CI 95% = 23.1 ± 10%, specificity CI 95% = 95.9 ± 2.5%) and with the bell-hammer sign in 23/65 cases (sensitivity CI 95% = 35.4 ± 11%, specificity CI 95% = 93.9 ± 3%). The association of the bell-hammer sign with conventional radiological diagnostic criteria has improved diagnosis performance of MRI for partial tears but not significantly (ns). The most important interest of the bell-hammer sign in the day-to-day clinical work is to suggest partial tears on MRI. It aids making a diagnosis, but its absence does not exclude partial ACL rupture. Diagnostic study, Level II.

Newberry exploratory slimhole: Drilling and testing

Energy Technology Data Exchange (ETDEWEB)

Finger, J.T.; Jacobson, R.D.; Hickox, C.E.

1997-11-01

During July--November, 1995, Sandia National Laboratories, in cooperation with CE Exploration, drilled a 5,360 feet exploratory slimhole (3.895 inch diameter) in the Newberry Known Geothermal Resource Area (KGRA) near Bend, Oregon. This well was part of Sandia`s program to evaluate slimholes as a geothermal exploration tool. During and after drilling the authors performed numerous temperature logs, and at the completion of drilling attempted to perform injection tests. In addition to these measurements, the well`s data set includes: over 4,000 feet of continuous core (with detailed log); daily drilling reports from Sandia and from drilling contractor personnel; daily drilling fluid record; and comparative data from other wells drilled in the Newberry KGRA. This report contains: (1) a narrative account of the drilling and testing, (2) a description of equipment used, (3) a brief geologic description of the formation drilled, (4) a summary and preliminary interpretation of the data, and (5) recommendations for future work.

Recurrent Hypothenar Hammer Syndrome: A Case Report.

Science.gov (United States)

Adams, Nicholas S; Ford, Ronald D

2016-10-01

Hypothenar hammer syndrome (HHS) is a rare cause of digital ischemia and pain caused from repetitive trauma to the palm. Often related to occupational practices, thrombosis and embolization can occur. Treatment is often surgical and involves excision with or without reconstruction. We describe a 55 year-old, male pipe fitter previously diagnosed and treated for HHS with excision and repair using a reversed interpositional vein graft in the mid-1980's. He continued to work in the profession, which he regularly used his palm as a hammer and returned approximately 30 years later with recurrent symptoms of cold intolerance and pain. Angiography confirmed occlusion of the ulnar artery with emboli present distally. The patient was again treated with excision and reconstruction. HHS is an uncommon cause of digital ischemia. Its recurrence is even more rare. To our knowledge, this is the first described case of diagnosed and treated recurrent HHS.

Muffling Hammer Blows In A Workshop

Science.gov (United States)

Thiele, Alfred W.; Gilbert, Jeffrey L.; Gutow, David A.

1994-01-01

Sound-deadening bags placed on hammered workpieces. Useful in many workshop situations. Fabricated easily and inexpensively. Bags filled with particles of sand, metal shot, plastic, or glass, then sewn or molded shut. Tailored to fit special configurations of some workpieces. Devices used to deaden print rollers and to reduce vibrations in main-injector inlet manifold of rocket engine.

Development of methodologies for coupled water-hammer analysis of piping systems and supports

International Nuclear Information System (INIS)

Kamil, H.; Gantayat, A.; Attia, A.; Goulding, H.

1983-01-01

The paper presents the results of an investigation on the development of methodologies for coupled water-hammer analyses. The study was conducted because the present analytical methods for calculation of loads on piping systems and supports resulting from water-hammer phenomena are overly conservative. This is mainly because the methods do not usually include interaction between the fluid and the piping and thus predict high loads on piping systems and supports. The objective of the investigation presented in this paper was to develop methodologies for coupled water-hammer analyses, including fluid-structure interaction effects, to be able to obtain realistic loads on piping systems and supports, resulting in production of more economical designs. (orig./RW)

Improving milling and production of a dust-producing unit equipped with hammer mills

Energy Technology Data Exchange (ETDEWEB)

Vorotnikov, Ye.G.; Nikiforov, A.A.; Rasputin, O.V.; Sukhunin, V.I.

1982-01-01

This paper presents generalized experience for deriving coarse ground coal dust in hammer mills by providing comparison data on improving efficiency of operation of the unit when switching to a coarser-type grind of the fuel. Need to have more precise formulas to calculate grinding potential of hammer mills when using a coarser grind is shown.

Lessons learned from the SONGS Unit 1 water hammer event

International Nuclear Information System (INIS)

Chiu, C.

1987-01-01

On November 21, 1985, a water hammer event occurred in horizontal feedwater line B at San Onofre Nuclear Generation Site (SONGS) Unit 1. The SONGS Unit 1 is a three-loop pressurized water reactor designed by Westinghouse Electric Corp. The event was initiated by a differential current trip on the bus of auxiliary transformer C. The root cause of the event was a simultaneous failure of five check valves in the feedwater system. Two of them are located downstream of the feedwater pump, and three of them are located further downstream and on the lines to the steam generators. The failure mechanism was determined to be flow-induced vibration, which caused repeated impact between the disk stud and the disk stop. The water hammer occurred in feedwater line B during the refilling of feedwater lines A, B, and C with auxiliary feedwater. The thermal-hydraulic process to initiate the water hammer and the reason that the water hammer only happened in line B have been fully investigated and explained. A root cause analysis after the event was prompted to answer the following two questions: (1) why did these five check valves fail at that time and not in the preceding 15 yr? (2) why did only these five check valves fail? The scope of the root cause analysis involves an investigation of the valve vibration characteristics, plant operation history, and the maintenance history of the valves. The paper answers these two questions, after a brief study of the vibration characteristics of a check valve

Structure and Conceptual Design of a Water-Hammering-Type Honsang for Restoration

Directory of Open Access Journals (Sweden)

Yong Sam Lee

2012-06-01

Full Text Available We analyzed the manufacturing procedure, specifications, repair history, and details of celestial movements of the water-hammering type Honsang (celestial globe. Results from our study on the remaining Honsangs in China and Japan and on the reconstruction models in Korea were applied to our conceptual design of the water-hammering type Honsang. A Honui (armillary sphere and Honsang using the water-hammering method were manufactured in Joseon in 1435 (the 17th year of King Sejong. Jang Yeong-Sil developed the Honsang system based on the water-operation method of Shui yün i hsiang t’ai in China. Water-operation means driving water wheels using a water flow. The most important factor in this type of operation is the precision of the water clock and the control of the water wheel movement. The water-hammering type Honsang in Joseon probably adopted the Cheonhyeong (天衡; oriental escapement device system of Shui yün i hsiang t’ai in China and the overflow mechanism of Jagyeongnu (striking clepsydra in Joseon, etc. In addition to the Cheonryun system, more gear instruments were needed to stage the rotation of the Honsang globe and the sun’s movement. In this study, the water-hammering mechanism is analyzed in the structure of a water clock, a water wheel, the Cheonhyeong system, and the Giryun system, as an organically working operation mechanism. We expect that this study will serve as an essential basis for studies on Heumgyeonggaknu, the water-operating astronomical clock, and other astronomical clocks in the middle and latter parts of the Joseon dynasty.

Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

CERN Document Server

Van der Ster , D; Medrano Llamas, R; Legger , F; Sciaba, A; Sciacca, G; Ubeda Garca , M

2012-01-01

Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion p...

Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

CERN Multimedia

CERN. Geneva

2012-01-01

Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion ...

Analysis of the drilling sound component from expert performance in a maxillo-facial surgery

DEFF Research Database (Denmark)

Hoffmann, Pablo F.; Gosselin, Florian; Taha, Farid

2009-01-01

Auditory displays can have a great potential in surgical simulators that aim at training skills associated to the correct interpretation of auditory information. Here, we present preliminary results in the analysis of the sound produced by the drilling procedure in a maxillo-facial surgery when...... performed by expert surgeons. The motivation of this work is to find relevant acoustic parameters that allow for an efficient synthesis method of auditory displays so that they can effectively convey information on expert surgical drilling....

Solenoid hammer valve developed for quick-opening requirements

Science.gov (United States)

Wrench, E. H.

1967-01-01

Quick-opening lightweight solenoid hammer valve requires a low amount of electrical energy to open, and closes by the restoring action of the mechanical springs. This design should be applicable to many quick-opening requirements in fluid systems.

Steel, hard metal and diamonds. The history of drilling blast holes in mining and tunneling; Stahl, Hartmetall und Diamanten. Zur Geschichte des Sprenglochbohrens im Berg- und Tunnelbau

Energy Technology Data Exchange (ETDEWEB)

Feistkorn, E. [Inst. fuer Vortrieb und Gewinnung, DMT-Gesellschaft fuer Forschung und Pruefung mbH, Essen (Germany)

1997-12-31

Beginning of the blasting technique in mining and tunneling during the 17th century required drilling holes to take the explosive. Following the use of hammer and wedge, drilling was done over a long period of time by hand with mallet and drillsteel. Continuously, during the 19th century the handwork was replaced by drilling machines. Technically, the evolution of drilling equipment is marked by electrohydraulic control and automatization with the assistance of microelectronics. Regarding the material, the introduction of hard metal and - in addition for rotary drilling - the development of synthetic diamond material are the main features. (orig.) [Deutsch] Mit der Einfuehrung der Sprengtechnik im Bergbau und Tunnelbau im 17. Jahrhundert mussten verfahrensbedingt Bohrloecher zur Aufnahme des Sprengstoffes hergestellt werden. In Anlehnung an die Arbeit mit Schlaegel und Eisen erfolgte dies lange Zeit manuell mit dem Bohrfaeustel und Stahlbohrern. Die Handarbeit wurde waehrend der 2. Haelfte des 19. Jahrhunderts kontinuierlich durch Bohrmaschinen verdraengt. Maschinentechnisch ist die weitere Entwicklung durch elektrohydraulische Steuerungen und die Automatisierung der Bohrgeraete mit Hilfe der Mikroelektronik gekennzeichnet. Materialtechnisch stellen die Einfuehrung des Hartmetalls und beim drehenden Bohren zusaetzlich die Entwicklung synthetischer Diamantwerkstoffe die herausragenden Marksteine dar. (orig.)

Study of cooling rates during metallic glass formation in a hammer and anvil apparatus

International Nuclear Information System (INIS)

Kroeger, D.M.; Coghlan, W.A.; Easton, D.S.; Koch, C.C.; Scarbrough, J.O.

1982-01-01

A model is presented of the simultaneous spreading and cooling of the liquid drop in a hammer and anvil apparatus for rapid quenching of liquid metals. The viscosity of the melt is permitted to vary with temperature, and to avoid mathematical complications which would be associated with spatial variation of the viscosity, Newtonian cooling is assumed. From an expression for the force required to spread the specimen, coupled equations for the mechanical energy balance for the system and the heat transfer from the sample to the hearth and hammer were obtained, and solved numerically. The sample reaches its final thickness when the force required to deform it becomes greater than the force exerted on it by the decelerating hammer. The model was fit to measurements of sample thickness versus hammer speed, using the interface heat transfer coefficient, h, as an adjustable parameter. The values of h so obtained vary somewhat with the melt alloy/substrate metal combination. From predicted cooling curves, the effects of hammer speed, sample size, and initial melt temperature on the cooling rate and the efficiency of glass formation can be assessed. Addition of sample superheat shifts the cooling curve relative to the expected position of the time-temperature-transformation curve for formation of crystalline material from the melt, and thus is an effective means of increasing the probability of glass formation in this type of apparatus

Improvement of Drill Performance in Metal Cutting Using MoST Solid Lubricant Coatings

Institute of Scientific and Technical Information of China (English)

N.R. Thomas; D.G. Teer; S. Yang; S. Hickman

2004-01-01

Coated tools are widely used in today's metal cutting industries and have significantly improved machining productivity through reducing operation costs and time. This paper presents the results of a systematic study of the performance of HSS drills coated with CrTiAlN and drills with a top solid lubricant coating of MoSTTM. The tests were performed on a Haas vertical machining centre under wet and dry cutting conditions to machine through holes in medium carbon steel workpieces. The feed force and torque were recorded throughout some of the tests using a force dynamometer,while the tool wear was monitored and measured. It was found that MoSTTM coatings even under accelerated conditions improve the tool life significantly based on their unique properties and very low friction.

A Water Hammer Protection Method for Mine Drainage System Based on Velocity Adjustment of Hydraulic Control Valve

Directory of Open Access Journals (Sweden)

Yanfei Kou

2016-01-01

Full Text Available Water hammer analysis is a fundamental work of pipeline systems design process for water distribution networks. The main characteristics for mine drainage system are the limited space and high cost of equipment and pipeline changing. In order to solve the protection problem of valve-closing water hammer for mine drainage system, a water hammer protection method for mine drainage system based on velocity adjustment of HCV (Hydraulic Control Valve is proposed in this paper. The mathematic model of water hammer fluctuations is established based on the characteristic line method. Then, boundary conditions of water hammer controlling for mine drainage system are determined and its simplex model is established. The optimization adjustment strategy is solved from the mathematic model of multistage valve-closing. Taking a mine drainage system as an example, compared results between simulations and experiments show that the proposed method and the optimized valve-closing strategy are effective.

Pushing the limits : from better bits to faster coil, companies leverage technology to ramp up onshore drilling performance

Energy Technology Data Exchange (ETDEWEB)

Smith, M.

2009-06-15

Horizontal drilling and drilling with coiled tubing are two well drilling techniques that have steadily gained ground in the drilling industry. Most of the techniques evolved in western Canada and Alaska, but are now being successfully used south of the border. This article discussed the leveraging of technology by drilling companies in order to ramp up onshore drilling performance. Calgary-based Xtreme Coil Drilling Corp. leveraged its unique coil over top drive rigs in order to score more speed records and set new marks in both the United States Rockies and Mexico. This article also referred to other companies and their wells that have set records, including CNX Gas Corporation and the Marcellus Shale prospect; Smith International and its horizontal turbodrilling of a Pennsylvanian reservoir; and Baker Oil Tools' new rotating, self-aligning multilateral (RAM) system. For each of these examples, the article described the technology and the challenges encountered by the companies as well as the objectives of the project, and results of the drilling efforts. 2 figs.

Identification of characteristic frequencies of damaged railway tracks using field hammer test measurements

Science.gov (United States)

Oregui, M.; Li, Z.; Dollevoet, R.

2015-03-01

In this paper, the feasibility of the Frequency Response Function (FRF)-based statistical method to identify the characteristic frequencies of railway track defects is studied. The method compares a damaged track state to a healthy state based on non-destructive field hammer test measurements. First, a study is carried out to investigate the repeatability of hammer tests in railway tracks. By changing the excitation and measurement locations it is shown that the variability introduced by the test process is negligible. Second, following the concepts of control charts employed in process monitoring, a method to define an approximate healthy state is introduced by using hammer test measurements at locations without visual damage. Then, the feasibility study includes an investigation into squats (i.e. a major type of rail surface defect) of varying severity. The identified frequency ranges related to squats agree with those found in an extensively validated vehicle-borne detection system. Therefore, the FRF-based statistical method in combination with the non-destructive hammer test measurements has the potential to be employed to identify the characteristic frequencies of damaged conditions in railway tracks in the frequency range of 300-3000 Hz.

A simple measurement hammer for quantitative reflex studies

NARCIS (Netherlands)

Stam, J.; van Leeuwen, J. R.

1984-01-01

A reflex hammer for measurement of the mechanical stimulus strength was designed. Combined with standard EMG equipment this instrument permits the study of both stimulus-response relations and latencies of myotatic reflexes. Some results in normal subjects are discussed

Theoretical calculation possibilities of the computer code HAMMER

International Nuclear Information System (INIS)

Onusic Junior, J.

1978-06-01

With the aim to know the theoretical calculation possibilities of the computer code HAMMER, developed at Savanah River Laboratory, a analysis of the crytical cells assembly of the kind utilized in PWR reactors is made. (L.F.S.) [pt

Comparison of energy measurements in the standard penetration test using the cathead and rope method. Phases I and II. Final report

International Nuclear Information System (INIS)

Kovacs, W.D.; Salomone, L.A.; Yokel, F.Y.

1983-11-01

Studies conducted on the Standard Penetration Test (SPT) and its present use in engineering practice show that a wide variation in the use of different pieces of SPT equipment, procedures and personnel results in a range of energy measured in the drill rods from 30 to 85 percent of the standard SPT energy. The potential energy and kinetic energy of the hammer were measured prior to impact, and the energy passing through the drill rods was calculated from a force-time measurement in the rods. It was found that safety (type) hammers tend to allow more kinetic energy to pass through the hammer-anvil system than donut (type) hammers. The energy passing through the drill rods was calculated by using a digital processing oscilloscope and an SPT Calibrator. Lessons learned in evaluating the energy measurement by these two methods are discussed. The combined effect of the drill rig used, the operator and his procedures, and the SPT equipment should be considered when energy is to be evaluated. The variation of average energy ratio within various drill rig models was found to be about as large as that among drill rig models. It was therefore impossible to make a statistically significant estimate of the reference energy which is representative of the average energy delivered in the US practice. 29 references, 24 figures, 20 tables

Compilation of data concerning know and suspected water hammer events in nuclear power plants, CY 1969

International Nuclear Information System (INIS)

Chapman, R.L.; Christensen, D.D.; Dafoe, R.E.; Hanner, O.M.; Wells, M.E.

1981-05-01

This report compiles data concerning known and suspected water hammer events reported by BWR and PWR power plants in the United States from January 1, 1969, to May 1, 1981. This information is summarized for each event and is tabulated for all events by plant, plant type, year of occurrence, type of water hammer, system affected, basis/cause for the event, and damage incurred. Information is also included from other events not specifically identified as water hammer related. These other events involved vibration and/or system components similar to those involved in the water hammer events. The other events are included to ensure completeness of the report, but are not used to point out particular facts or trends. This report does not evaluate findings abstracted from the data

Water hammer phenomena occurring in nuclear power installations while filling horizontal pipe containing saturated steam with liquid

Energy Technology Data Exchange (ETDEWEB)

Selivanov, Y.F.; Kirillov, P.L.; Yefanov, A.D. [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

1995-09-01

The potentiality of the water hammer occurrence in nuclear reactor loop components has been considered under the conditions of filling a steam-containing pipeline leg involving horizontal and vertical sections with liquid subcooled to the saturation temperature. As a result of free discharging from the tank, the liquid enters the horizontal pipeline. When the liquid slug formation in the pipeline is fulfilled. The pressure drop being occurred in steam flowing along the pipelines causes the liquid slug to move to the pipeline inlet. When the liquid slug decelerates, a water hammer occurs. This mechanism of water hammer occurrence is tested by experiments. The regimes of the occurrence of multiple considerable water hammers were identified.

Water hammer phenomena occurring in nuclear power installations while filling horizontal pipe containing saturated steam with liquid

International Nuclear Information System (INIS)

Selivanov, Y.F.; Kirillov, P.L.; Yefanov, A.D.

1995-01-01

The potentiality of the water hammer occurrence in nuclear reactor loop components has been considered under the conditions of filling a steam-containing pipeline leg involving horizontal and vertical sections with liquid subcooled to the saturation temperature. As a result of free discharging from the tank, the liquid enters the horizontal pipeline. When the liquid slug formation in the pipeline is fulfilled. The pressure drop being occurred in steam flowing along the pipelines causes the liquid slug to move to the pipeline inlet. When the liquid slug decelerates, a water hammer occurs. This mechanism of water hammer occurrence is tested by experiments. The regimes of the occurrence of multiple considerable water hammers were identified

A study on the initiation of condensation-induced water hammer in a long horizontal pipe

International Nuclear Information System (INIS)

Park, Joo Wan

1992-02-01

Condensation-induced water hammer (CIWH) is the most severe and has the highest frequency among the water hammer events occurred in nuclear power plants. Among mechanisms associated with this type of water hammer, the steam and water countercurrent flow in a horizontal pipe is known as the dominant mechanism in Pressurized Water Reactors. The CIWH due to steam-water counter-flow in a long horizontal pipe has been analytically investigated with emphasis on the effect of pipe length, in order to identify the conditions necessary to initiate a water hammer and to provide stability maps describing the zone of water hammer to be avoided with the combination of filling water flowrate and pipe length. Analytical models which can be used to predict the limiting boundaries, upper and lower one, of CIWH initiation have been developed and the calculation results have been compared with the data of an actual incident occurred previously in a nuclear power plant. From the approach used in this study, boundary estimates including simple relationships between critical inlet water flowrates and pipe length-to-diameter on the CIWH initiation in a long horizontal pipe could be made, and several corrective actions to prevent water hammer recurrence could be taken. However, because of the limited understanding of the direct-contact condensation phenomena in the typical range of nuclear power plant operation, it is likely that the overall uncertainty of the analysis results will be high. Therefore, further research on this area including scaling analysis is required

Water hammer prediction and control: the Green's function method

Science.gov (United States)

Xuan, Li-Jun; Mao, Feng; Wu, Jie-Zhi

2012-04-01

By Green's function method we show that the water hammer (WH) can be analytically predicted for both laminar and turbulent flows (for the latter, with an eddy viscosity depending solely on the space coordinates), and thus its hazardous effect can be rationally controlled and minimized. To this end, we generalize a laminar water hammer equation of Wang et al. (J. Hydrodynamics, B2, 51, 1995) to include arbitrary initial condition and variable viscosity, and obtain its solution by Green's function method. The predicted characteristic WH behaviors by the solutions are in excellent agreement with both direct numerical simulation of the original governing equations and, by adjusting the eddy viscosity coefficient, experimentally measured turbulent flow data. Optimal WH control principle is thereby constructed and demonstrated.

Hypothenar hammer syndrome and basilic bypass.

Science.gov (United States)

Chander, R K; Phair, J; Oza, P; Patel, M; Balar, N

2014-12-01

We report a case of hypothenar hammer syndrome. The case presents necessary diagnostic measures and discusses the etiology of this syndrome. Additionally, the case reviews treatments, which culminated in the eventual use of ulnar artery bypass with autogenous basilica vein to treat and resolve the ischemic fingers of the patient. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Evaluation of water-hammer experience in nuclear power plants. Technical findings relevant to Unresolved Safety Issue A-1

International Nuclear Information System (INIS)

Serkiz, A.W.

1983-05-01

This report summarizes key technical findings relevant to the Unresolved Safety Issue A-1, Water Hammer. These findings were derived from studies of reported water hammer occurrences and underlying causes and provide key insights into means to minimize or eliminate further water hammer occurrences. It should also be noted that this report does not represent a substitute for current rules and regulations

Evaluation of water hammer occurrence in nuclear power plants: technical findings relevant to unresolved safety issue A-1

International Nuclear Information System (INIS)

1984-03-01

This report, which includes responses to public comments, summarizes key technical findings relevant to the Unresolved Safety Issue A-1, Water Hammer. These findings were derived from studies of reported water hammer occurrences and underlying causes and provide key insights into means to minimize or eliminate further water hammer occurrences. This report does not represent a substitute for current rules and regulations

Modeling Friction Performance of Drill String Torsional Oscillation Using Dynamic Friction Model

Directory of Open Access Journals (Sweden)

Xingming Wang

2017-01-01

Full Text Available Drill string torsional and longitudinal oscillation can significantly reduce axial drag in horizontal drilling. An improved theoretical model for the analysis of the frictional force was proposed based on microscopic contact deformation theory and a bristle model. The established model, an improved dynamic friction model established for drill strings in a wellbore, was used to determine the relationship of friction force changes and the drill string torsional vibration. The model results were in good agreement with the experimental data, verifying the accuracy of the established model. The analysis of the influence of drilling mud properties indicated that there is an approximately linear relationship between the axial friction force and dynamic shear and viscosity. The influence of drill string torsional oscillation on the axial friction force is discussed. The results indicated that the drill string transverse velocity is a prerequisite for reducing axial friction. In addition, low amplitude of torsional vibration speed can significantly reduce axial friction. Then, increasing the amplitude of transverse vibration speed, the effect of axial reduction is not significant. In addition, by involving general field drilling parameters, this model can accurately describe the friction behavior and quantitatively predict the frictional resistance in horizontal drilling.

Fluid dynamic interaction between water hammer and centrifugal pumps

International Nuclear Information System (INIS)

Ismaier, A.; Schluecker, E.

2009-01-01

Centrifugal pumps generate in piping systems noticeable pressure pulsations. In this paper the dynamic interaction between water hammer and pressure pulsations is presented. The experimental investigations were performed at a piping system with nominal diameter DN 100 (respectively NPS 4) and 75 m total length, built at the Institute for Process Technology and Machinery. Different measurements at this testing facility show that pulsating centrifugal pumps can damp pressure surges generated by fast valve closing. It is also shown that 1-dimensional fluid codes can be used to calculate this phenomenon. Furthermore it is presented that pressure surges pass centrifugal pumps almost unhindered, because they are hydraulic open.

Testing as a Service with HammerCloud

CERN Document Server

Medrano Llamas, Ramón; Elmsheuser, Johannes; Legger, Federica; Sciacca, Gianfranco; Sciabà, Andrea; van der Ster, Daniel

2014-01-01

HammerCloud was designed and born under the needs of the grid community to test the resources and automate operations from a user perspective. The recent developments in the IT space propose a shift to the software defined data centres, in which every layer of the infrastructure can be offered as a service. Testing and monitoring is an integral part of the development, validation and operations of big systems, like the grid. This area is not escaping the paradigm shift and we are starting to perceive as natural the Testing as a Service (TaaS) offerings, which allow testing any infrastructure service, such as the Infrastructure as a Service (IaaS) platforms being deployed in many grid sites, both from the functional and stressing perspectives. This work will review the recent developments in HammerCloud and its evolution to a TaaS conception, in particular its deployment on the Agile Infrastructure platform at CERN and the testing of many IaaS providers across Europe in the context of experiment requirements....

The Hammer Award is presented to KSC and 45th Space Wing.

Science.gov (United States)

1999-01-01

KSC's Director of Public Affairs Joe Gordon (left) applauds as Ed Gormel and Chris Fairey are named recipients of the Hammer Award at a special presentation in the IMAX 2 Theater in the Kennedy Space Center Visitor Complex. Presenting the award is Morley Winograd (at the podium), director of the National Partnership for Reinventing Government. The Hammer Award is Vice President Al Gore's special recognition of teams of federal employees who have made significant contributions in support of the principles of the National Partnership for Reinventing Government. This Hammer Award acknowledges the accomplishments of a joint NASA and Air Force team that established the Joint Base Operations and Support Contract (J-BOSC) Source Evaluation Board (SEB). Gormel and Fairey are co-chairs of the SEB. The team developed and implemented the acquisition strategy for establishing a single set of base operations and support service requirements for KSC, Cape Canaveral Air Station and Patrick Air Force Base.

Conceptual design report, Hazardous Materials Management and Emergency Response (HAMMER) Training Center

Energy Technology Data Exchange (ETDEWEB)

Kelly, K.E. [Westinghouse Hanford Co., Richland, WA (United States)

1994-11-09

For the next 30 years, the main activities at the US Department of Energy (DOE) Hanford Site will involve the management, handling, and cleanup of toxic substances. If the DOE is to meet its high standards of safety, the thousands of workers involved in these activities will need systematic training appropriate to their tasks and the risks associated with these tasks. Furthermore, emergency response for DOE shipments is the primary responsibility of state, tribal, and local governments. A collaborative training initiative with the DOE will strengthen emergency response at the Hanford Site and within the regional communities. Local and international labor has joined the Hazardous Materials Management and Emergency Response (HAMMER) partnership, and will share in the HAMMER Training Center core programs and facilities using their own specialized trainers and training programs. The HAMMER Training Center will provide a centralized regional site dedicated to the training of hazardous material, emergency response, and fire fighting personnel.

Conceptual design report, Hazardous Materials Management and Emergency Response (HAMMER) Training Center

International Nuclear Information System (INIS)

Kelly, K.E.

1994-01-01

For the next 30 years, the main activities at the US Department of Energy (DOE) Hanford Site will involve the management, handling, and cleanup of toxic substances. If the DOE is to meet its high standards of safety, the thousands of workers involved in these activities will need systematic training appropriate to their tasks and the risks associated with these tasks. Furthermore, emergency response for DOE shipments is the primary responsibility of state, tribal, and local governments. A collaborative training initiative with the DOE will strengthen emergency response at the Hanford Site and within the regional communities. Local and international labor has joined the Hazardous Materials Management and Emergency Response (HAMMER) partnership, and will share in the HAMMER Training Center core programs and facilities using their own specialized trainers and training programs. The HAMMER Training Center will provide a centralized regional site dedicated to the training of hazardous material, emergency response, and fire fighting personnel

Condensation driven water hammer studies for feedwater distribution pipe

Energy Technology Data Exchange (ETDEWEB)

Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J. [Imatran Voima Oy, Vantaa (Finland); Pullinen, J. [IVO Power Engineering Ltd., Vantaa (Finland); Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K. [EDO Gidropress (Russian Federation)

1997-12-31

Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.).

Condensation driven water hammer studies for feedwater distribution pipe

International Nuclear Information System (INIS)

Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J.; Pullinen, J.; Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K.

1997-01-01

Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.)

Condensation driven water hammer studies for feedwater distribution pipe

Energy Technology Data Exchange (ETDEWEB)

Savolainen, S; Katajala, S; Elsing, B; Nurkkala, P; Hoikkanen, J [Imatran Voima Oy, Vantaa (Finland); Pullinen, J [IVO Power Engineering Ltd., Vantaa (Finland); Logvinov, S A; Trunov, N B; Sitnik, J K [EDO Gidropress (Russian Federation)

1998-12-31

Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.).

Well drilling by rotary percussive drill above ground

International Nuclear Information System (INIS)

Sabatier, G.

1987-01-01

Originally, the Well Drilling Section of Cogema used only the diamond core drilling technique. The appearance of independent rotation for compressed air rock drills has led to the use and to the development of this drilling system, as a drill core is not indispensable, when the material of the search is radioactive. During the last few years, hydraulic drills have replaced the compressed air drills and have resulted in a very marked improvement: - of the penetration rates; - of the depth achieved. The Well Drilling Section of Cogema has to drill about 400 km per year with rock drills above ground and holds also the record for depth achieved with this technique, i.e. 400 m in granite. In France, the costs of these types of drilling are for the same depth of the order of one-quarter of the core drilling and half of the drilling with a down-the-hole drill. Cogema has greatly developed the types of well logging which now permits the extension of this type of drilling to the search for other materials than uranium [fr

Pressure and wall shear stress in blood hammer - Analytical theory.

Science.gov (United States)

Mei, Chiang C; Jing, Haixiao

2016-10-01

We describe an analytical theory of blood hammer in a long and stiffened artery due to sudden blockage. Based on the model of a viscous fluid in laminar flow, we derive explicit expressions of oscillatory pressure and wall shear stress. To examine the effects on local plaque formation we also allow the blood vessel radius to be slightly nonuniform. Without resorting to discrete computation, the asymptotic method of multiple scales is utilized to deal with the sharp contrast of time scales. The effects of plaque and blocking time on blood pressure and wall shear stress are studied. The theory is validated by comparison with existing water hammer experiments. Copyright © 2016. Published by Elsevier Inc.

Impact of pipes networks simplification on water hammer phenomenon

Indian Academy of Sciences (India)

problem; the finite difference method using water hammer and mass oscillation ... Mohamed (2003) introduced the effect of different parameters such as time of valve closure, ..... for computing the water age equivalent diameter, Dew. Dew = ⎡.

Prey selection of a captive Oystercatcher Haematopus ostralegus hammering Mussels Mytilus edulis from the ventral side

NARCIS (Netherlands)

Ens, Bruno J.; Alting, D

1996-01-01

We studied prey choice of a captive Oystercatcher:hat hammered Mussels from the ventral side. The results replicate previous findings that ventral hammerers select Mussels of intermediate size, select against thick-shelled Mussels, abandon an increasing proportion of Mussels with increasing size and

Analytical study on water hammer pressure in pressurized conduits with a throttled surge chamber for slow closure

Directory of Open Access Journals (Sweden)

Yong-liang Zhang

2010-06-01

Full Text Available This paper presents an analytical investigation of water hammer in a hydraulic pressurized pipe system with a throttled surge chamber located at the junction between a tunnel and a penstock, and a valve positioned at the downstream end of the penstock. Analytical formulas of maximum water hammer pressures at the downstream end of the tunnel and the valve were derived for a system subjected to linear and slow valve closure. The analytical results were then compared with numerical ones obtained using the method of characteristics. There is agreement between them. The formulas can be applied to estimating water hammer pressure at the valve and transmission of water hammer pressure through the surge chamber at the junction for a hydraulic pipe system with a surge chamber.

Potential fatigue strength improvement of AA 5083-H111 notched parts by wire brush hammering: Experimental analysis and numerical simulation

International Nuclear Information System (INIS)

Sidhom, Naziha; Moussa, Naoufel Ben; Janeb, Sameh; Braham, Chedly; Sidhom, Habib

2014-01-01

Highlights: • Wire brush hammering increases by 20% the AA 5083-H111 notched parts fatigue limit. • Improvement of fatigue strength is related to the fatigue cracks nucleation. • Fatigue strength prediction accounts for wire brush hammering effects. - Abstract: The effects of milling as machining process and a post-machining treatment by wire-brush hammering, on the near surface layer characteristics of AA 5083-H111 were investigated. Surface texture, work-hardening and residual stress profiles were determined by roughness measurement, scanning electron microscope (SEM) examinations, microhardness and X-ray diffraction (XRD) measurements. The effects of surface preparation on the fatigue strength were assessed by bending fatigue tests performed on notched samples for two loading stress ratios R 0.1 and R 0.5 . It is found that the bending fatigue limit at R 0.1 and 10 7 cycles is 20% increased, with respect to the machined surface, by wire-brush hammering. This improvement was discussed on the basis of the role of surface topography, stabilized residual stress and work-hardening on the fatigue-crack network nucleation and growth. The effects biaxial residual stress field and surface work-hardening were taken into account in the finite element model. A multi-axial fatigue criterion was proposed to predict the fatigue strength of aluminum alloy notched parts for both machined and treated states

Assessing hospital disaster preparedness: a comparison of an on-site survey, directly observed drill performance, and video analysis of teamwork.

Science.gov (United States)

Kaji, Amy H; Langford, Vinette; Lewis, Roger J

2008-09-01

There is currently no validated method for assessing hospital disaster preparedness. We determine the degree of correlation between the results of 3 methods for assessing hospital disaster preparedness: administration of an on-site survey, drill observation using a structured evaluation tool, and video analysis of team performance in the hospital incident command center. This was a prospective, observational study conducted during a regional disaster drill, comparing the results from an on-site survey, a structured disaster drill evaluation tool, and a video analysis of teamwork, performed at 6 911-receiving hospitals in Los Angeles County, CA. The on-site survey was conducted separately from the drill and assessed hospital disaster plan structure, vendor agreements, modes of communication, medical and surgical supplies, involvement of law enforcement, mutual aid agreements with other facilities, drills and training, surge capacity, decontamination capability, and pharmaceutical stockpiles. The drill evaluation tool, developed by Johns Hopkins University under contract from the Agency for Healthcare Research and Quality, was used to assess various aspects of drill performance, such as the availability of the hospital disaster plan, the geographic configuration of the incident command center, whether drill participants were identifiable, whether the noise level interfered with effective communication, and how often key information (eg, number of available staffed floor, intensive care, and isolation beds; number of arriving victims; expected triage level of victims; number of potential discharges) was received by the incident command center. Teamwork behaviors in the incident command center were quantitatively assessed, using the MedTeams analysis of the video recordings obtained during the disaster drill. Spearman rank correlations of the results between pair-wise groupings of the 3 assessment methods were calculated. The 3 evaluation methods demonstrated

Analysis of water hammer phenomena - Application to deaerator-feedwater pump node

International Nuclear Information System (INIS)

Bigu, Melania; Tenescu, Mircea; Nita, Iulian Pavel

2008-01-01

The hydraulic hammer adverse effects are extensively presented in the literature available to those who operate and design installations in which this phenomenon occurs. There are specialized computational programs which evaluate diverse technical aspects which occur in this phenomenon. One must be noticed that not all the technical characteristics and not all effective operating modes which are treated in this paper are covered by existing computational programs. Moreover, even specialized developers of such programs recommend insistently that computational results offered by specialized programs to be verified by specialized technologists with experience in alternative theoretical computations in order to avoid any misinterpretation of results obtained by computational codes. After selective exposures of theoretical fundamentals of the problem there are presented a computational calculation obtained using the specialized calculation code PIPENET (Sunrise System Limited, Cambridge, Great Britain). The PIPENET calculation is compared with a standard computational calculation using theoretical correlations. An evaluation of the differences between those two computational methods is made in order to reveal the capabilities of the computational codes in solving the hydraulic hammering problems. In the first stage we obtained the elastic characteristics of the pipe where the phenomena of hydraulic hammering takes place. There are derivative descriptions of differential equations which describe the physical phenomena. In the second part we carried out a complete system analysis of water hammer effect due to a faulty closing of the four level control valves in steam generators. We compared the highest attended pressure with design pressure of the system. We observed that the design pressure is not overpassed. The analysis concluded that pumps' head protection is a very important parameter against overpressure in the feed water system. (authors)

Study for increasing micro-drill reliability by vibrating drilling

International Nuclear Information System (INIS)

Yang Zhaojun; Li Wei; Chen Yanhong; Wang Lijiang

1998-01-01

A study for increasing micro-drill reliability by vibrating drilling is described. Under the experimental conditions of this study it is observed, from reliability testing and the fitting of a life-distribution function, that the lives of micro-drills under ordinary drilling follow the log-normal distribution and the lives of micro-drills under vibrating drilling follow the Weibull distribution. Calculations for reliability analysis show that vibrating drilling can increase the lives of micro-drills and correspondingly reduce the scatter of drill lives. Therefore, vibrating drilling increases the reliability of micro-drills

Multiple performance characteristics optimization for Al 7075 on electric discharge drilling by Taguchi grey relational theory

Science.gov (United States)

Khanna, Rajesh; Kumar, Anish; Garg, Mohinder Pal; Singh, Ajit; Sharma, Neeraj

2015-12-01

Electric discharge drill machine (EDDM) is a spark erosion process to produce micro-holes in conductive materials. This process is widely used in aerospace, medical, dental and automobile industries. As for the performance evaluation of the electric discharge drilling machine, it is very necessary to study the process parameters of machine tool. In this research paper, a brass rod 2 mm diameter was selected as a tool electrode. The experiments generate output responses such as tool wear rate (TWR). The best parameters such as pulse on-time, pulse off-time and water pressure were studied for best machining characteristics. This investigation presents the use of Taguchi approach for better TWR in drilling of Al-7075. A plan of experiments, based on L27 Taguchi design method, was selected for drilling of material. Analysis of variance (ANOVA) shows the percentage contribution of the control factor in the machining of Al-7075 in EDDM. The optimal combination levels and the significant drilling parameters on TWR were obtained. The optimization results showed that the combination of maximum pulse on-time and minimum pulse off-time gives maximum MRR.

An Analysis of the Impact of Valve Closure Time on the Course of Water Hammer

Science.gov (United States)

Kodura, Apoloniusz

2016-06-01

The knowledge of transient flow in pressure pipelines is very important for the designing and describing of pressure networks. The water hammer is the most common example of transient flow in pressure pipelines. During this phenomenon, the transformation of kinetic energy into pressure energy causes significant changes in pressure, which can lead to serious problems in the management of pressure networks. The phenomenon is very complex, and a large number of different factors influence its course. In the case of a water hammer caused by valve closing, the characteristic of gate closure is one of the most important factors. However, this factor is rarely investigated. In this paper, the results of physical experiments with water hammer in steel and PE pipelines are described and analyzed. For each water hammer, characteristics of pressure change and valve closing were recorded. The measurements were compared with the results of calculations perfomed by common methods used by engineers - Michaud's equation and Wood and Jones's method. The comparison revealed very significant differences between the results of calculations and the results of experiments. In addition, it was shown that, the characteristic of butterfly valve closure has a significant influence on water hammer, which should be taken into account in analyzing this phenomenon. Comparison of the results of experiments with the results of calculations? may lead to new, improved calculation methods and to new methods to describe transient flow.

Understanding how the placement of an asymmetric vibration damping tool within drilling while underreaming can influence performance and reliability

Energy Technology Data Exchange (ETDEWEB)

Kabbara, Alan; McCarthy, John; Burnett, Timm; Forster, Ian [National Oilwell Varco Downhole Ltd. (NOV), Houston, TX (United States)

2012-07-01

This paper describes the work, on test rigs and full-scale drilling rigs, carried out with respect to placement of an Asymmetric Vibration Damping Tool (AVDT) within drilling while under reaming operations. An AVDT, by virtue of the forward synchronous motion imposed on the drill string, offers benefits in minimizing down hole vibration-related tool failures and therefore maximizing rate of penetration (ROP). Of interest in using the AVDT is the tendency to minimize stick slip by means of the parasitic torque it generates. This is of particular importance during under reaming operations. While under reaming, stick slip can result in low (ROP) and potentially an increased incidence of down hole tool failures. The use of an AVDT in these operations has been shown to significantly reduce stick slip. However, due to the forward synchronous motion caused by the AVDT, there is the potential to cause eccentric wear to the Bottom Hole Assembly (BHA) components in the vicinity of the AVDT. If allowed to progress, this eccentric wear can cause a reduction in down hole tool life and drilling performance. Eliminating eccentric wear would be beneficial in reducing repair costs, extending component life and further improving drilling performance. To minimize eccentric wear and maximize drilling performance, the placement of the AVDT within the BHA is critical. This paper describes how the placement of intermediate stabilizers between the AVDT and the under reamer can minimize eccentric wear to the under reamer and the adjacent drill string due to the forward synchronous whirl induced by the AVDT. This approach allows the full benefits of the AVDT to be recognized while reducing the potentially damaging effects of eccentric wear to other BHA components. The work has drawn upon small-scale rig testing, full-scale testing at the Ullrigg test facility in Norway and from real-world drilling and under reaming operations in the USA. (author)

Water hammer with column separation : a historical review

NARCIS (Netherlands)

Bergant, A.; Simpson, A.R.; Tijsseling, A.S.

2006-01-01

Column separation refers to the breaking of liquid columns in fully filled pipelines. This may occur in a water-hammer event when the pressure in a pipeline drops to the vapor pressure at specific locations such as closed ends, high points or knees (changes in pipe slope). The liquid columns are

Aerated drilling cutting transport analysis in geothermal well

Science.gov (United States)

Wakhyudin, Aris; Setiawan, Deni; Dwi Marjuan, Oscar

2017-12-01

Aeratad drilling widely used for geothermal drilling especially when drilled into predicted production zone. Aerated drilling give better performance on preventing lost circulation problem, improving rate of penetration, and avoiding drilling fluid invasion to productive zone. While well is drilled, cutting is produced and should be carried to surface by drilling fluid. Hole problem, especially pipe sticking will occur while the cutting is not lifted properly to surface. The problem will effect on drilling schedule; non-productive time finally result more cost to be spent. Geothermal formation has different characteristic comparing oil and gas formation. Geothermal mainly has igneous rock while oil and gas mostly sedimentary rock. In same depth, formation pressure in geothermal well commonly lower than oil and gas well while formation temperature geothermal well is higher. While aerated drilling is applied in geothermal well, Igneous rock density has higher density than sedimentary rock and aerated drilling fluid is lighter than water based mud hence minimum velocity requirement to transport cutting is larger than in oil/gas well drilling. Temperature and pressure also has impact on drilling fluid (aerated) density. High temperature in geothermal well decrease drilling fluid density hence the effect of pressure and temperature also considered. In this paper, Aerated drilling cutting transport performance on geothermal well will be analysed due to different rock and drilling fluid density. Additionally, temperature and pressure effect on drilling fluid density also presented to merge.

Benchmarks solutions of the coupled systems NJOY/AMPX-II/HAMMER-TECHNION and the library JENDL-3

International Nuclear Information System (INIS)

Santos, A. dos

1991-01-01

Benchmarks calculations were performed with the newest released japanese nuclear data library JENDL-3. The calculations were performed with the methodology developed at IPEN/CNEN-SP based on a coupled NJOY/AMPX-II/HAMMER-TECHNION system. The analyses show that the long-standing problem of the overprediction of the epithermal U-238 neutron capture still remains. Besides that there is an indication that the fission cross section of U-238 might be underestimated. (author)

In-process and post-process measurements of drill wear for control of the drilling process

Science.gov (United States)

Liu, Tien-I.; Liu, George; Gao, Zhiyu

2011-12-01

Optical inspection was used in this research for the post-process measurements of drill wear. A precision toolmakers" microscope was used. Indirect index, cutting force, is used for in-process drill wear measurements. Using in-process measurements to estimate the drill wear for control purpose can decrease the operation cost and enhance the product quality and safety. The challenge is to correlate the in-process cutting force measurements with the post-process optical inspection of drill wear. To find the most important feature, the energy principle was used in this research. It is necessary to select only the cutting force feature which shows the highest sensitivity to drill wear. The best feature selected is the peak of torque in the drilling process. Neuro-fuzzy systems were used for correlation purposes. The Adaptive-Network-Based Fuzzy Inference System (ANFIS) can construct fuzzy rules with membership functions to generate an input-output pair. A 1x6 ANFIS architecture with product of sigmoid membership functions can in-process measure the drill wear with an error as low as 0.15%. This is extremely important for control of the drilling process. Furthermore, the measurement of drill wear was performed under different drilling conditions. This shows that ANFIS has the capability of generalization.

Wave Stresses in the Anvil Hammer Rods under Impact Including Ram Mass and Deformation Force of Forgings

Directory of Open Access Journals (Sweden)

V. M. Sinitskiy

2016-01-01

Full Text Available When operating the anvil hammers there occur impacts of die tooling and as a consequence, virtually instantaneous impact stops of motion of drop hammer parts. Such operating conditions come with accelerated failures of the anvil hammer rods because of emerging significant wave stresses. Engineering practice widely uses variation, difference, and integral methods to calculate wave stresses. However, to use them a researcher has to acquire certain skills, and the special programs should be available. The paper considers a method for estimating the wave stress changes in the anvil hammer rods, which is based on the wave equation of the Laplace transform. It presents a procedure for generating differential equations and their solution using the operator method. These equations describe the wave processes of strain and stress propagation in the anvil hammer rod under non-rigid impact with the compliance obstacle of the drop hammer parts. The work defines how the piston and rod mass and also the mechanical and geometric parameters of the rod influence on the stress level in the rod sealing of the hammer ram. Analysis of the results shows that the stresses in the rod sealing are proportional to the total amount of wave stresses caused by the rod and piston impact included in the total weight of the system. The piston influence on the stresses in the rod under impact is in direct proportion to the ratio of its mass to the mass of the rod. Geometric parameters of the rod and speed of drop parts before the impact influence on the stress value as well. It was found that if the time of impact is less than the time of the shock wave running in forward and backward direction, the impact with a compliance obstacle is equivalent to that of with a rigid obstacle, and the dependence of the wave stresses follows the Zhukovsky formula of direct pressure shock. The presented method of stress calculation can be successfully used to select the optimal mass and the rod

Polyethylene glycol drilling fluid for drilling in marine gas hydrates-bearing sediments: an experimental study

Energy Technology Data Exchange (ETDEWEB)

Jiang, G.; Liu, T.; Ning, F.; Tu, Y.; Zhang, L.; Yu, Y.; Kuang, L. [China University of Geosciences, Faculty of Engineering, Wuhan (China)

2011-07-01

Shale inhibition, low-temperature performance, the ability to prevent calcium and magnesium-ion pollution, and hydrate inhibition of polyethylene glycol drilling fluid were each tested with conventional drilling-fluid test equipment and an experimental gas-hydrate integrated simulation system developed by our laboratory. The results of these tests show that drilling fluid with a formulation of artificial seawater, 3% bentonite, 0.3% Na{sub 2}CO{sub 3}, 10% polyethylene glycol, 20% NaCl, 4% SMP-2, 1% LV-PAC, 0.5% NaOH and 1% PVP K-90 performs well in shale swelling and gas hydrate inhibition. It also shows satisfactory rheological properties and lubrication at temperature ranges from -8 {sup o}C to 15 {sup o}C. The PVP K-90, a kinetic hydrate inhibitor, can effectively inhibit gas hydrate aggregations at a dose of 1 wt%. This finding demonstrates that a drilling fluid with a high addition of NaCl and a low addition of PVP K-90 is suitable for drilling in natural marine gas-hydrate-bearing sediments. (authors)

Polyethylene Glycol Drilling Fluid for Drilling in Marine Gas Hydrates-Bearing Sediments: An Experimental Study

Directory of Open Access Journals (Sweden)

Lixin Kuang

2011-01-01

Full Text Available Shale inhibition, low-temperature performance, the ability to prevent calcium and magnesium-ion pollution, and hydrate inhibition of polyethylene glycol drilling fluid were each tested with conventional drilling-fluid test equipment and an experimental gas-hydrate integrated simulation system developed by our laboratory. The results of these tests show that drilling fluid with a formulation of artificial seawater, 3% bentonite, 0.3% Na2CO3, 10% polyethylene glycol, 20% NaCl, 4% SMP-2, 1% LV-PAC, 0.5% NaOH and 1% PVP K-90 performs well in shale swelling and gas hydrate inhibition. It also shows satisfactory rheological properties and lubrication at temperature ranges from −8 °C to 15 °C. The PVP K-90, a kinetic hydrate inhibitor, can effectively inhibit gas hydrate aggregations at a dose of 1 wt%. This finding demonstrates that a drilling fluid with a high addition of NaCl and a low addition of PVP K-90 is suitable for drilling in natural marine gas-hydrate-bearing sediments.

Hammering towards QED

Directory of Open Access Journals (Sweden)

Jasmin C. Blanchette

2016-01-01

Full Text Available This paper surveys the emerging methods to automate reasoning over large libraries developed with formal proof assistants. We call these methods hammers. They give the authors of formal proofs a strong "one-stroke" tool for discharging difficult lemmas without the need for careful and detailed manual programming of proof search.The main ingredients underlying this approach are efficient automatic theorem provers that can cope with hundreds of axioms, suitable translations of richer logics to their formalisms, heuristic and learning methods that select relevant facts from large libraries, and methods that reconstruct the automatically found proofs inside the proof assistants.We outline the history of these methods, explain the main issues and techniques, and show their strength on several large benchmarks. We also discuss the relation of this technology to the QED Manifesto and consider its implications for QED-style efforts.

Modeling of Comparative Performance of Asphalt Concrete under Hammer, Gyratory, and Roller Compaction

Directory of Open Access Journals (Sweden)

Saad I. Sarsam

2016-11-01

Full Text Available The main objective of this study is to develop predictive models using SPSS software (version 18 for Marshall Test results of asphalt mixtures compacted by Hammer, Gyratory, and Roller compaction. Bulk density of (2.351 gm/cc, at OAC of (4.7 % was obtained as a benchmark after using Marshall Compactor as laboratory compactive effort with 75-blows. Same density was achieved by Roller and Gyratory Compactors using its mix designed methods. A total of (75 specimens, for Marshall, Gyratory, and Roller Compactors have been prepared, based on OAC of (4.7 % with an additional asphalt contents of more and less than (0.5 % from the optimum value. All specimens have been subjected to Marshall Test. Mathematical models obtained indicated that variation of Marshall Stiffness is based on the variation of air voids. All of these models depend on asphalt cement content too.

Studi Numerik Variasi Pemilihan Gas Accumulator Untuk Pencegahan Water Hammer Pada Sistem Perpipaan Sepanjang 1 Kilometer dan Debit Aliran 800 GPM

Directory of Open Access Journals (Sweden)

Anindika Bagus Pradana

2013-09-01

Full Text Available Sistem jaringan perpipaan sangat penting dalam menunjang produksi pada bidang industri. Jaringan perpipaan mengalami beberapa fenomena seperti distribusi fluida dan water hammer. Water hammer sering terjadi di daerah discharge pompa saat pengoperasian dan gagalnya beroperasinya pompa. Water hammer dapat merusak jaringan perpipaan. Fenomena water hammer dapat terjadi hampir di setiap sistem instalasi perpipaan. Fenomena ini mempunyai dampak buruk apabila sistem perpipaan tersebut tidak memperhatikan akibat dari water hammer. Fenomena dalam sistem perpipaan mempunyai dampak negatif dengan selang waktu tertentu, water hammer adalah fenomena dimana dampak yang ditimbulkan terjadi seketika itu juga. Penanggulangan yang tidak tepat terhadap dampak tersebut dapat mengakibatkan instalasi tersebut harus dimatikan (shutdown. Pada simulasi ini digunakan sistem instalasi perpipaan dengan panjang 1 kilometer dan debit aliran 800 gpm.Pada sistem instalasi ini memiliki rangkaian pompa tunggal yang dilengkapi dengan gas accumulator di sisi discharge pompa. Ketika terjadi perubahan flow rate yang menyebabkan pompa beroprasi atau gagal beroprasi akan menimbulkan fenomena water hammer.Penelitian dilakukan secara numerik menggunakan software AFT Impulse 4.0. Water hammer dapat diminimalisi dengan memasang gas accumulator pada daerah dekat discharge pompa. Variasi gas accumulator adalah gas accumulator merk NOK tipe AT 175-20 dengan volume maksimum 20 liter, tipe AT 210-60 dengan volume maksimum 60 liter dan tipe AT 230-120 dengan volume maksimum 100 liter. Hasil yang didapatkan pada simulasi menunjukan pada jarak 4 meter dari rumah pompa masing-masing P max dan P min  untuk sistem perpipaan dengan simulasi proses trip pompa tanpa proteksi water hammer adalah 1729 Kpa dan 381 Kpa, untuk sistem perpipaan dengan gas accumulator volume setting 20 liter adalah 1228 Kpa dan 927 Kpa, untuk sistem perpipaan dengan gas accumulator volume setting 60 liter adalah 1161 Kpa

Simulation of water hammer phenomena using the system code ATHLET

Energy Technology Data Exchange (ETDEWEB)

Bratfisch, Christoph; Koch, Marco K. [Bochum Univ. (Germany). Reactor Simulation and Safety Group

2017-07-15

Water Hammer Phenomena can endanger the integrity of structures leading to a possible failure of pipes in nuclear power plants as well as in many industrial applications. These phenomena can arise in nuclear power plants in the course of transients and accidents induced by the start-up of auxiliary feed water systems or emergency core cooling systems in combination with rapid acting valves and pumps. To contribute to further development and validation of the code ATHLET (Analysis of Thermalhydraulics of Leaks and Transients), an experiment performed in the test facility Pilot Plant Pipework (PPP) at Fraunhofer UMSICHT is simulated using the code version ATHLET 3.0A.

Simulation of water hammer phenomena using the system code ATHLET

International Nuclear Information System (INIS)

Bratfisch, Christoph; Koch, Marco K.

2017-01-01

Water Hammer Phenomena can endanger the integrity of structures leading to a possible failure of pipes in nuclear power plants as well as in many industrial applications. These phenomena can arise in nuclear power plants in the course of transients and accidents induced by the start-up of auxiliary feed water systems or emergency core cooling systems in combination with rapid acting valves and pumps. To contribute to further development and validation of the code ATHLET (Analysis of Thermalhydraulics of Leaks and Transients), an experiment performed in the test facility Pilot Plant Pipework (PPP) at Fraunhofer UMSICHT is simulated using the code version ATHLET 3.0A.

Graphene nanoplatelets as high-performance filtration control material in water-based drilling fluids

Science.gov (United States)

Ridha, Syahrir; Ibrahim, Arif; Shahari, Radzi; Fonna, Syarizal

2018-05-01

The main objective of this work is to evaluate the effectiveness of graphene nanoplatelets (GNP) as filtration control materials in water based drilling fluids. Three (3) general samples of water based drilling fluids were prepared including basic potassium chloride (KCl) drilling fluids, nanosilica (NS) drilling fluids and GNP drilling fluids. Several concentrations of NS and GNP were dispersed in controlled formulations of water based drilling fluids. Standard API filtration tests were carried out for comparison purposes as well as High Temperature High Pressure (HTHP) filtration tests at 150 °F (∼66 °C), 250 °F (∼121 °C) and 350 °F (∼177 °C) at a fixed 500 (∼3.45MPa) psi to study the filtration trend as a function of temperature. Mud cake samples from several tests were selectively chosen and analyzed under Field Emission Scanning Electron Microscope (FESEM) for its morphology. Results from this work show that nanoparticle concentrations play a factor in filtration ability of colloid materials in water based drilling fluids when studied at elevated temperature. Low temperature filtration, however, shows only small differences in volume in all the drilling fluid samples. 0.1 ppb concentrations of GNP reduced the fluid loss of 350 °F by 4.6 mL as compared to the similar concentration of NS drilling fluids.

Linear or Rotary Actuator Using Electromagnetic Driven Hammer as Prime Mover

Science.gov (United States)

Paine, Jeffrey S. N. (Inventor); Smith, Byron F. (Inventor); Sesler, Joshua J. (Inventor); Paine, Matthew T. (Inventor); McMahan, Bert K. (Inventor); McMahan, Mark C. (Inventor)

2018-01-01

We claim a hammer driven actuator that uses the fast-motion, low-force characteristics of an electro-magnetic or similar prime mover to develop kinetic energy that can be transformed via a friction interface to produce a higher-force, lower-speed linear or rotary actuator by using a hammering process to produce a series of individual steps. Such a system can be implemented using a voice-coil, electro-mechanical solenoid or similar prime mover. Where a typical actuator provides limited range of motion or low force, the range of motion of a linear or rotary impact driven motor can be configured to provide large displacements which are not limited by the characteristic dimensions of the prime mover.

Calculation of fluid (steam) hammer loading to piping systems by the response spectrum method

International Nuclear Information System (INIS)

Krause, G.; Schrader, W.; Leimbach, K.R.

1983-01-01

Today computations of fluid and steam hammer loading to piping systems are usually performed as a time-history analysis in which the transient pressure forces act as external excitations. For practical purposes it is desirable to be able to treat fluid hammer loading using the response spectrum method similarily as loads from external events. Two advantages arise from the use of spectra in the analysis of piping systems subjected to dynamic force excitations. Firstly, the response spectrum method is much less sensitive to model idealization than the time-history method. Secondly, computational efforts are reduced. In this paper the algorithm for the treatment of force excitations through the modal response spectrum method is briefly presented. The effect of the residuum accounting for higher modes which are not part of the modal decomposition is considered. In particular various methods of superposition of the responses of the dynamic forces and of the modes are investigated. Results and comparisons are presented of several response spectrum analyses and time-history analyses. (orig.)

Transient Analysis for Evaluating the Potential Boiling in the High Elevation Emergency Cooling Units of PWR Following a Hypothetical Loss of Coolant Accident (LOCA) and Subsequent Water Hammer Due to Pump Restart

International Nuclear Information System (INIS)

Husaini, S. Mahmood; Qashu, Riyad K.

2004-01-01

The Generic Letter GL-96-06 issued by the U.S. Nuclear Regulatory Commission (NRC) required the utilities to evaluate the potential for voiding in their Containment Emergency Cooling Units (ECUs) due to a hypothetical Loss Of Coolant Accident (LOCA) or a Main Steam Line Break (MSLB) accompanied by the Loss Of Offsite Power (LOOP). When the offsite power is restored, the Component Cooling Water (CCW) pumps restart causing water hammer to occur due to cavity closure. Recently EPRI (Electric Power Research Institute) performed a research study that recommended a methodology to mitigate the water hammer due to cavity closure. The EPRI methodology allows for the cushioning effects of hot steam and released air, which is not considered in the conventional water column separation analysis. The EPRI study was limited in scope to the evaluation of water hammer only and did not provide any guidance for evaluating the occurrence of boiling and the extent of voiding in the ECU piping. This paper presents a complete methodology based on first principles to evaluate the onset of boiling. Also, presented is a methodology for evaluating the extent of voiding and the water hammer resulting from cavity closure by using an existing generalized computer program that is based on the Method of Characteristics. The EPRI methodology is then used to mitigate the predicted water hammer. Thus it overcomes the inherent complications and difficulties involved in performing hand calculations for water hammer. The heat transfer analysis provides an alternative to the use of very cumbersome modeling in using CFD (computational fluid dynamics) based computer programs. (authors)

The Performance of Corporate Alliances: Evidence from Oil and Gas Drilling in the Gulf of Mexico

OpenAIRE

Beshears, John Leonard

2013-01-01

I use data on oil and gas drilling in the Gulf of Mexico to measure how a corporate alliance—a group of firms that jointly develops an offshore tract—performs relative to a solo firm. I employ a regression discontinuity strategy based on bids in first-price sealed-bid auctions for the rights to develop leases. By focusing on leases where one organizational form narrowly outbids the other, I measure drilling outcomes while controlling for the endogenous matching of projects and organizational ...

HAMOC: a computer program for fluid hammer analysis

International Nuclear Information System (INIS)

Johnson, H.G.

1975-12-01

A computer program has been developed for fluid hammer analysis of piping systems attached to a vessel which has undergone a known rapid pressure transient. The program is based on the characteristics method for solution of the partial differential equations of motion and continuity. Column separation logic is included for situations in which pressures fall to saturation values

Impact of pipes networks simplification on water hammer phenomenon

Indian Academy of Sciences (India)

Simplification of water supply networks is an indispensible design step to make the original network easier to be analysed. The impact of networks' simplification on water hammer phenomenon is investigated. This study uses two loops network with different diameters, thicknesses, and roughness coefficients. The network is ...

Drop Hammer Tests with Three Oleo Strut Models and Three Different Shock Strut Oils at Low Temperatures

Science.gov (United States)

Kranz, M

1954-01-01

Drop hammer tests with different shock strut models and shock strut oils were performed at temperatures ranging to -40 C. The various shock strut models do not differ essentially regarding their springing and damping properties at low temperatures; however, the influence of the different shock strut oils on the springing properties at low temperatures varies greatly.

Steam condensation induced water hammer simulations for different pipelines

International Nuclear Information System (INIS)

Barna, I.F.; Ezsol, G.

2011-01-01

We investigate steam condensation induced water hammer (CIWH) phenomena and present theoretical results for different kind of pipelines. We analyze the process with the WAHA3 model based on two-phase flow six first-order partial differential equations that present one dimensional, surface averaged mass, momentum and energy balances. A second order accurate high-resolution shock-capturing numerical scheme was applied with different kind of limiters in the numerical calculations. At first, we present calculations for various pipelines in the VVER-440-312 type nuclear reactor. Our recent calculation clearly shows that the six conditions of Griffith are only necessary conditions for CIWH but not sufficient. As second results we performed calculations for various geometries and compare with the theory of Chun. (author)

Counterevidence to the ion hammering scenario as a driving force for the shape elongation of embedded nanoparticles

Science.gov (United States)

Amekura, H.; Okubo, N.; Tsuya, D.; Ishikawa, N.

2017-08-01

Counterevidence is provided in the ion-hammering scenario as a driving force for the shape elongation of embedded nanoparticles (NPs) under swift heavy ion irradiation (SHII). Ion-induced compaction and the hammering, which are both induced in silica under SHII, dominate at low and high fluences, respectively, causing a crossover between them around a fluence of ˜4 × 1012 ions/cm2. Nevertheless, the shape elongation of NPs detected by the optical dichroism exhibits nearly linear dependence in a wide fluence range between ˜1 × 1011 and 2 × 1013 ions/cm2, indicating that the hammering does not play an important role.

Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography

Energy Technology Data Exchange (ETDEWEB)

Winterer, J.T.; Ghanem, N.; Schaefer, O.; Lehnhardt, S.; Thuerl, C.; Laubenberger, J. [Department of Diagnostic Radiology, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Roth, M. [Center of Geriatric Medicine and Gerontology Freiburg, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany); Horch, R.E. [Department of Plastic and Hand Surgery, University of Freiburg, Hugstetter Strasse 55, 79106 Freiburg (Germany)

2002-10-01

Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained. (orig.)

Diagnosis of the hypothenar hammer syndrome by high-resolution contrast-enhanced MR angiography

International Nuclear Information System (INIS)

Winterer, J.T.; Ghanem, N.; Schaefer, O.; Lehnhardt, S.; Thuerl, C.; Laubenberger, J.; Roth, M.; Horch, R.E.

2002-01-01

Our objective was to describe the imaging features of hypothenar hammer syndrome using minimally invasive contrast-enhanced MR angiography in comparison with oscillography study. In five patients with hypothenar hammer syndrome Gd-BOPTA-enhanced elliptically reordered 3D pulse sequence MR was compared with oscillography findings and clinical symptoms focusing on angiographic appearance of vessel injury, distribution pattern of hand vasculature and joining branches between the radial and ulnar artery supply. All patients showed segmental occlusion at the site of trauma impact with varying involvement of the superficial palmar arch, common volar digital arteries. Embolic disease was present in 50% of patients and could be clearly identified with MRA. Good correspondence was found between angiographic appearance including the presence of collaterals, clinical symptoms and oscillography. Bilateral comparison was helpful in distinguishing between vessel variants and pathology. Bilateral Gd-BOPTA-enhanced MR angiography is a minimally invasive method to depict clearly the localization and extent of vessel injury in hypothenar hammer syndrome providing valuable information about distribution pattern of hand vasculature and presence of collaterals; however, no flow data can be obtained. (orig.)

Water hammer caused by rapid steam production in a severe accident in a light water reactor

International Nuclear Information System (INIS)

Inasaka, Fujio; Adachi, Masaki; Murata, Hiroyuki; Aya, Izuo

2007-01-01

We conducted the experimental studies on the water hammer caused by striking of a water mass pushed up by a rapidly growing steam bubble, using a cylindrical model containment vessel of 0.4286 m in diameter. In the experiments, a rapid gas growth was simulated by injecting high-pressure steam into a water pool. It was clarified that coherency of the water mass movement and its water hammer caused by the condensable gas production considerably decreased in comparison with the case of the non-condensable gas production because the rising velocity of the water mass was suppressed due to the steam bubble condensation. On the basis of the data, experimental correlations for estimating the water hammer on the structures in the containment vessel were proposed. (author)

THE LEVEL AND AGE DYNAMICS OF SPORTS ACHIEVEMENTS OF ATHLETES-VETERANS OF THE HAMMER THROW

Directory of Open Access Journals (Sweden)

Ivanova Natalya Dmitrievna

2013-03-01

Full Text Available The article presents the records of the world and Russian athletes veterans in the hammer throw, starting with the age group 35-39 years and up to age group 100-104 years, and a comparison of the records of veterans subject to an age factor and of the high scores of athletes in the current sports. The aim of the work is to analyze the level and dynamics of the records of the world and Russian athletes, veterans in the hammer throw in each five-year group starting with the age group 35-39 years and up to age group 100-104 years. The novelty of the work consists in comparison of the records of the world and Russia in the hammer throw active athletes and records of veterans with the amendment to the age factor. Analysis of the level and age dynamics of sports achievements of domestic and foreign athletes-throwers older age groups. In the course of the research it is established, that in the throwing hammer, decreasing absolute (without regard to the age factor results, which is largely due to the natural age-related changes in the organism of athletes. Records of the world athletes-veterans compared with the records of active athletes and the transition from each of the five-year group in the following, decline on average in men by 10,0%, among women by 19,3%, in spite of the fact that the weight of the shells in the hammer throw with age decreases. Presented the reasons for the backwardness of Russian athletes older than 35 years of foreign veterans.

Automatic real time drilling support on Ekofisk utilizing eDrilling

Energy Technology Data Exchange (ETDEWEB)

Rommetveit, Rolv; Bjorkevoll, Knut S.; Halsey, George W.; Kluge, Roald; Molde, Dag Ove; Odegard, Sven Inge [SINTEF Petroleum Research, Trondheim (Norway); Herbert, Mike [HITEC Products Drilling, Stavanger (Norway); ConocoPhillips Norge, Stavanger (Norway)

2008-07-01

eDrilling is a new and innovative system for real time drilling simulation, 3D visualization and control from a remote drilling expert centre. The concept uses all available real time drilling data (surface and downhole) in combination with real time modelling to monitor and optimize the drilling process. This information is used to visualize the wellbore in 3D in real time. eDrilling has been implemented in an Onshore Drilling Center in Norway. The system is composed of the following elements, some of which are unique and ground-breaking: an advanced and fast Integrated Drilling Simulator which is capable to model the different drilling sub-processes dynamically, and also the interaction between these sub-processes in real time; automatic quality check and corrections of drilling data; making them suitable for processing by computer models; real time supervision methodology for the drilling process using time based drilling data as well as drilling models / the integrated drilling simulator; methodology for diagnosis of the drilling state and conditions. This is obtained from comparing model predictions with measured data. Advisory technology for more optimal drilling. A Virtual Wellbore, with advanced visualization of the downhole process. Dat low and computer infrastructure. e-Drilling has been implemented in an Onshore Drilling Center on Ekofisk in Norway. The system is being used on drilling operations, and experiences from its use are presented. The supervision and diagnosis functionalities have been useful in particular, as the system has given early warnings on ECD and friction related problems. This paper will present the eDrilling system as well as experiences from its use. (author)

Drilling Experiments of Dummy Fuel Rods Using a Mock-up Drilling Device and Detail Design of Device for Drilling of Irradiated Nuclear Fuel Rods

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Yong; Lee, H. K.; Chun, Y. B.; Park, S. J.; Kim, B. G

2007-07-15

KAERI are developing the safety evaluation method and the analysis technology for high burn-up nuclear fuel rod that is the project, re-irradiation for re-instrumented fuel rod. That project includes insertion of a thermocouple in the center hole of PWR nuclear fuel rod with standard burn-up, 3,500{approx}4,000MWD/tU and then inspection of the nuclear fuel rod's heat performance during re-irradiation. To re-fabricate fuel rod, two devices are needed such as a drilling machine and a welding machine. The drilling machine performs grinding a center hole, 2.5 mm in diameter and 50 mm in depth, for inserting a thermocouple. And the welding machine is used to fasten a end plug on a fuel rod. Because these two equipment handle irradiated fuel rods, they are operated in hot cell blocked radioactive rays. Before inserting any device into hot cell, many tests with that machine have to be conducted. This report shows preliminary experiments for drilling a center hole on dummy of fuel rods and optimized drilling parameters to lessen operation time and damage of diamond dills. And the design method of a drilling machine for irradiated nuclear fuel rods and detail design drawings are attached.

IMPACT OF ROCK HARDNESS ON FRAGMENTATION BY HYDRAULIC HAMMER AND CRUSHING IN JAW CRUSHER

Directory of Open Access Journals (Sweden)

Trpimir Kujundžić

2008-12-01

Full Text Available The physical and mechanical characteristics of intact rocks depend on the way of their formation, sustained deformations and the process of wearing a specific rock has been exposed to. These characteristics have a rather high influence on the technological process of extraction and dressing of mineral raw materials. However, the mechanical characteristics of rocks due to use of explosives for their extraction in the open pit have a more significant impact. The rock blocks extracted by blasting which are larger than the opening of the primary crusher are usually fragmented by hydraulic hammer. The paper presents the results of the testing of impact of rock hardness on fragmentation of rocks by means of hydraulic hammer and during crushing in jaw crusher. The testing was carried out on the rock samples from five quarries. According to the obtained results the hardness has a considerably larger impact on the fragmentation energy by hydraulic hammer than on the crushing energy in jaw crusher.

Evaluation of SPT energy for Donut and Safety hammers using CPT measurements in Egypt

Directory of Open Access Journals (Sweden)

Rami M. El-Sherbiny

2013-12-01

Full Text Available Standard Penetration Test (SPT blow counts require correction prior to utilization in soil characterization and determination of properties and behavior. Among the most important corrections is the energy correction required to adjust the blow counts to 60% energy efficiency. However, there are no published data supporting commonly used value in Egypt. This paper presents an evaluation of the energy efficiency of the Donut and Safety hammers commonly used in Egypt and the associated energy correction factor. The energy efficiency is estimated by comparing N-values from the SPT to back-calculated N60 values from the Cone Penetration Test (CPT using well established correlations. Results indicate that the energy efficiency of the Donut hammer based on current practice in Egypt is approximately 50%. Thus, the back-calculated energy correction factor is approximately 0.82. For the Safety hammer, results indicate that the energy efficiency is approximately 60%, and the energy correction factor is approximately 1.0.

Water Hammer Modelling and Simulation by GIS

Directory of Open Access Journals (Sweden)

K. Hariri Asli

2012-01-01

Full Text Available This work defined an Eulerian-based computational model compared with regression of the relationship between the dependent and independent variables for water hammer surge wave in transmission pipeline. The work also mentioned control of Unaccounted-for-Water (UFW based on the Geography Information System (GIS for water transmission pipeline. The experimental results of laboratory model and the field test results showed the validity of prediction achieved by computational model.

Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

NARCIS (Netherlands)

Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

2011-01-01

Fluid-structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

Fluid-structure interaction with pipe-wall viscoelasticity during water hammer

NARCIS (Netherlands)

Keramat, A.; Tijsseling, A.S.; Hou, Q.; Ahmadi, A.

2012-01-01

Fluid–structure interaction (FSI) due to water hammer in a pipeline which has viscoelastic wall behaviour is studied. Appropriate governing equations are derived and numerically solved. In the numerical implementation of the hydraulic and structural equations, viscoelasticity is incorporated using

New drilling optimization technologies make drilling more efficient

Energy Technology Data Exchange (ETDEWEB)

Chen, D.C.-K. [Halliburton Energy Services, Calgary, AB (Canada). Sperry Division

2004-07-01

Several new technologies have been adopted by the upstream petroleum industry in the past two decades in order to optimize drilling operations and improve drilling efficiency. Since financial returns from an oil and gas investment strongly depend on drilling costs, it is important to reduce non-productive time due to stuck pipes, lost circulation, hole cleaning and well bore stability problems. The most notable new technologies are the use of computer-based instrumentation and data acquisition systems, integrated rig site systems and networks, and Measurement-While-Drilling and Logging-While-Drilling (MWD/LWD) systems. Drilling optimization should include solutions for drillstring integrity, hydraulics management and wellbore integrity. New drilling optimization methods emphasize information management and real-time decision making. A recent study for drilling in shallow water in the Gulf of Mexico demonstrates that trouble time accounts for 25 per cent of rig time. This translates to about $1.5 MM U.S. per well. A reduction in trouble time could result in significant cost savings for the industry. This paper presents a case study on vibration prevention to demonstrate how the drilling industry has benefited from new technologies. 13 refs., 10 figs.

Casing drilling

Energy Technology Data Exchange (ETDEWEB)

Heenan, D. [Tesco Corp., Calgary, AB (Canada)

2003-07-01

This paper reviewed the experience that Tesco has gained by drilling several wells using only casings as the drill stem. Tesco has manufactured a mobile and compact hydraulic drilling rig called the Casing Drilling {sup TM} system. The system could be very effective and efficient for exploration and development of coalbed methane (CBM) reserves which typically require extensive coring. Continuous coring while drilling ahead, along wire line retrieval, can offer time savings and quick core recovery of large diameter core which is typically required for exploration core desorption tests. The proposed system may also have the potential to core or drill typically tight gas sands or underbalanced wells with air or foam. This would reduce drilling fluid damage while simultaneously finding gas. Compared to conventional drill pipes, Casing Drilling {sup TM} could also be effective with water production from shallow sands because of the smaller annual clearance which requires less air volumes to lift any produced water. 9 figs.

Research on water hammer forces caused by rapid growth of bubbles at severe accidents of water cooled reactors

International Nuclear Information System (INIS)

Inasaka, Fujio; Adachi, Masaki; Aya, Izuo

2004-01-01

At severe accidents of Water Cooled Reactors a great deal of gas is expected to be produced in a short time within the water of lower part of nuclear pressure vessel and containment vessel caused by hydrogen production with a metal water reaction and steam explosions with direct contact of melting core and water. Water hammer forces caused by rapid growth of bubbles shall work on the wall of containment vessel and affect its integrity. Coherency of water block movement is not clear, whether simultaneous or in the same direction. Water block behavior and water hammer forces caused by rapid growth of bubbles have been tested using a modified scale model and analyzed to obtain experimental correlated equation to estimate water block's rising distance and velocity from water hammer data. Numerical analysis using RELAP5-3D (Reactor Excursion and Leak Analysis Program) has been conducted to evaluate water hammer forces and makes clear its modifications needed. (T. Tanaka)

Fatigue analysis of aluminum drill pipes

Directory of Open Access Journals (Sweden)

João Carlos Ribeiro Plácido

2005-12-01

Full Text Available An experimental program was performed to investigate the fundamental fatigue mechanisms of aluminum drill pipes. Initially, the fatigue properties were determined through small-scale tests performed in an optic-mechanical fatigue apparatus. Additionally, full-scale fatigue tests were carried out with three aluminum drill pipe specimens under combined loading of cyclic bending and constant axial tension. Finally, a finite element model was developed to simulate the stress field along the aluminum drill pipe during the fatigue tests and to estimate the stress concentration factors inside the tool joints. By this way, it was possible to estimate the stress values in regions not monitored during the fatigue tests.

Experimental evaluation of ability of Relap5 and DRAKO to calculate water hammer with phase changes

International Nuclear Information System (INIS)

Marcinkiewicz, Jerzy; Adamkowski, Adam; Lewandowski, Mariusz

2007-01-01

Mechanical loadings on pipe systems caused by water hammer with phase changes make calculation of final forces difficult in nuclear power plants. The common procedure in Sweden is to calculate the water hammer loadings, according to the classical one-dimensional theory of liquid transient flow in pipeline, and then transfer the results to strength analyses of pipeline structure. This procedure assumes that there is quasi-steady response of the pipeline structure to pressure surges - no dynamic interaction between the fluid and the pipeline construction. The hydraulic loadings are calculated with 1-D so-called 'network' programs. Commonly used in Sweden are Relap5 (Mod3.2.2 and higher) and Drako. As a third party accredited inspection body INSPECTA NUCLEAR AB reviews calculations of water hammer loadings. An important question for the reviewer (and also for the users) is knowledge about their ability to calculate the dynamic loadings. While the ability of Relap5 and DRAKO to calculate water hammer without phase changes is relatively well investigated the skills of the programs when phase changes are present need some more attention. The presented work shall be seen as an attempt to illustrate ability of Relap5, and Drako programs to calculate the water hammer loadings with phase changes. A special attention was paid to using of Relap5 for calculation of water hammer pressure surges (including some aspects of influence of discretisation of space on the calculation results). The calculations are compared with experimental results. The experiments have been conducted at a test rig designed and constructed at the Szewalski Institute of Fluid-Flow Machinery of the Polish Academy of Sciences (IMP PAN) in Gdansk, Poland. The comparison of calculated and measured pressures shows some differences, only the first pressure peak, occurring before evaporation is calculated quite exactly. All next coming pressure peaks differ slightly from the measured with respect to amplitude

The hammer QSD-quick stop device for high speed machining and rubbing

Science.gov (United States)

Black, J. T.; James, C. R.

1980-01-01

A quick stop device (QSD) was designed for use in orthogonal machining and rubbing experiments. QSD's are used to obtain chip root samples that are representative of the deformation taking place during dynamic (actual) cutting conditions. These 'frozen' specimens are helpful in examining the plastic deformation that occurs in the regions of compression and shear which form the chip; the secondary shear at the tool-chip interface; and the nose ploughing/flank rubbing action which operates on the newly machined surface. The Hammer QSD employs a shear pin mechanism, broken by a flying hammer, which is traveling at the same velocity as the workpiece. The device has been successfully tested up to 6000 sfpm (30.48 m/sec).

Water hammer (with FSI): exact solution : parallelization and application

NARCIS (Netherlands)

Loh, K.; Tijsseling, A.S.

2014-01-01

The 1D fully coupled Fluid-Structure Interaction (FSI) model can adequately describe the water hammer effect on the fluid, and the structural behaviour of the pipe. This paper attempts to increase the capability of using an exact solution of the 1D FSI problem applied to a straight pipe with a

The influence of the non-Newtonian properties of blood on blood-hammer through the posterior cerebral artery.

Science.gov (United States)

Tazraei, Pedram; Riasi, Alireza; Takabi, Behrouz

2015-06-01

This work investigates a two dimensional numerical analysis of blood hammer through the posterior cerebral artery. The non-Newtonian and usual Newtonian blood models are compared in the case of blood hammer through the posterior cerebral artery to quantify the differences between the models. In this way, a validated CFD simulation is used to study non-Newtonian shear-thinning effects of blood. The governing equations for the modeling of two-dimensional transient flow are solved using a combination of characteristics and central finite difference methods, respectively for the hyperbolic and parabolic parts. Herein, the non-Newtonian viscosity characteristic of blood is incorporated by using the Carreau model. To convert the nonlinear terms available in the characteristics equation into the linear ones, the Newton-Kantorovich method is implemented. The verification and validation of the numerical results are carried out in detail. Hemodynamic characteristics of blood hammer through the posterior cerebral artery are derived with both the Newtonian and non-Newtonian models, and the results are meticulously compared and discussed. The results show that when blood hammer occurs, the non-Newtonian properties greatly influence the velocity and shear stress profiles. At the early stages of blood hammer, there is a 64% difference between magnitudes of wall shear stress in these two models, and the magnitude of the wall shear stress for the shear-thinning blood flow is lower than the Newtonian one. Copyright © 2015 Elsevier Inc. All rights reserved.

A Hybrid Resynthesis Model for Hammer-String Interaction of Piano Tones

Directory of Open Access Journals (Sweden)

Jensen Kristoffer

2004-01-01

Full Text Available This paper presents a source/resonator model of hammer-string interaction that produces realistic piano sound. The source is generated using a subtractive signal model. Digital waveguides are used to simulate the propagation of waves in the resonator. This hybrid model allows resynthesis of the vibration measured on an experimental setup. In particular, the nonlinear behavior of the hammer-string interaction is taken into account in the source model and is well reproduced. The behavior of the model parameters (the resonant part and the excitation part is studied with respect to the velocities and the notes played. This model exhibits physically and perceptually related parameters, allowing easy control of the sound produced. This research is an essential step in the design of a complete piano model.

Drilling and well technology

Energy Technology Data Exchange (ETDEWEB)

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

1996-12-31

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.

Cavitation luminescence in a water hammer: Upscaling sonoluminescence

Science.gov (United States)

Su, C.-K.; Camara, C.; Kappus, B.; Putterman, S. J.

2003-06-01

Oscillatory acceleration and deceleration of a column of water leads to a pipe hammer as well as cavitation. With a small amount of xenon gas dissolved in the water, we can detect a stream of predominantly ultraviolet subnanosecond flashes of light which are attributed to collapsing bubbles. The observed emission can exceed 108 photons for a single collapse and has a peak power over 0.4 W.

Heat generated by dental implant drills during osteotomy-a review: heat generated by dental implant drills.

Science.gov (United States)

Mishra, Sunil Kumar; Chowdhary, Ramesh

2014-06-01

Osseointegration is the more stable situation and results in a high success rate of dental implants. Heat generation during rotary cutting is one of the important factors influencing the development of osseointegration. To assess the various factors related to implant drills responsible for heat generation during osteotomy. To identify suitable literature, an electronic search was performed using Medline and Pubmed database. Articles published in between 1960 to February 2013 were searched. The search is focused on heat generated by dental implant drills during osteotomy. Various factors related to implant drill such effect of number of blades; drill design, drill fatigue, drill speed and force applied during osteotomies which were responsible for heat generation were reviewed. Titles and abstracts were screened, and literature that fulfilled the inclusion criteria was selected for a full-text reading. The initial literature search resulted in 299 articles out of which only 70 articles fulfils the inclusion criteria and were included in this systematic review. Many factors related to implant drill responsible for heat generation were found. Successful preparation of an implant cavity with minimal damage to the surrounding bone depends on the avoidance of excessive temperature generation during surgical drilling. The relationship between heat generated and implant drilling osteotomy is multifactorial in nature and its complexity has not been fully studied. Lack of scientific knowledge regarding this issue still exists. Further studies should be conducted to determine the various factors which generate less heat while osteotomy such as ideal ratio of force and speed in vivo, exact time to replace a drill, ideal drill design, irrigation system, drill-bone contact area.

Water hammer with fluid-structure interaction in thick-walled pipes

NARCIS (Netherlands)

Tijsseling, A.S.

2007-01-01

A one-dimensional mathematical model is presented which describes the acoustic behaviour of thick-walled liquid-filled pipes. The model is based on conventional water-hammer and beam theories. Fluid–structure interaction (FSI) is taken into account. The equations governing straight pipes are derived

The effect of drilling parameters for surface roughness in drilling of AA7075 alloy

Directory of Open Access Journals (Sweden)

Yaşar Nafiz

2017-01-01

Full Text Available AA7075 aluminum alloy has been very popular significantly interest in the production of structural components in automotive and aviation applications due to its high strength, low density, good plasticity and better machinability comparable to many metals. Particularly, final products must have uniformly high quality to ensure essential safety standards in the aircraft industry. The optimization of hole quality which can variable according to tool geometry and drilling parameters is important in spite of high machinability rate of AA7075 alloy. In this study, the effects of drilling parameters on average surface roughness (Ra has been investigated in drilling of AA7075 with tungsten carbide drills. Machining experiments were performed with three different drill point angles and three different levels of cutting parameters (feed rate, cutting speed. The effects of drilling parameters on thrust force has been determined with ANOVA in %95 confidence level. Feed rate was determined as the most important factor on Ra according to ANOVA results. Moreover, it was shown that increasing feed rate leads to increase of Ra while increasing drill point angle leads to decrease of Ra. The optimum surface roughness was obtained with point angle of 130°, cutting speed of 40 m/min and feed rate of 0.1 mm/rev, thereby the validity of optimization was confirmed with Taguchi method.

STUDY OF WATER HAMMERS IN THE FILLING OF THE SYSTEM OF PRESSURE COMPENSATION IN THE WATER-COOLED AND WATER-MODERATED POWER REACTORS

Directory of Open Access Journals (Sweden)

A. V. Korolyev

2017-01-01

Full Text Available The research presented in the article conforms to the severe accident that took place at the Three Mail Island nuclear power plant in the USA. The research is focused on improving the reliability of the pressure compensator that is an important equipment of the primary circuit. In order to simulate such a situation, the stand has been developed to simulate the design of the pressurizer of the PWR-440 reactor, in particular an elliptical shape of the upper lid which has a steam outlet pipe at the top of the construction that creates conditions for occurrence of such water hammers. For the experiments, an installation has been created that makes it possible to measure and record the water hammering that occur when the tanks are filled. Measurement of the amplitude of the water hammering was carried out by a specially developed piezoelectric sensor, and the registration – by a light-beam oscilloscope. The technique of carrying out the experiment is described and the results of an experimental study of the water hammers arising when the vessels are completely filled are presented. Quantitative data were obtained on the amplitudes of the hydraulic impacts depending on the rate of filling of the vessel and the diameter of the outlet, the maximum pressure of the hydraulic shock was 7–9 atm. Comparison of calculated and experimental data has been performed. The allowable discrepancy is explained by the calculated value of the system stiffness coefficient, which did not take into account the presence of welded seams in the tank that imparts the system with additional rigidity. The calculated relationships are obtained, that make it possible to estimate the amplitudes of the water hammers through the acceleration of the water level in front of the outlet from a vessel with an elliptical bottom. The possibility of a water hammer in the pressure compensator is demonstrated by experiment and by theoretical calculations. Based on the experimental data, a

Importance of drill string assembly swivel in horizontal drilling

Directory of Open Access Journals (Sweden)

Edmund Tasak

2006-10-01

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.

Comparative study of conventional and ultrasonically-assisted bone drilling.

Science.gov (United States)

Alam, K; Ahmed, Naseer; Silberschmidt, V V

2014-01-01

Bone drilling is a well-known surgical procedure in orthopaedics and dentistry for fracture treatment and reconstruction. Advanced understanding of the mechanics of the drill-bone interaction is necessary to overcome challenges associated with the process and related postoperative complications. The aim of this study was to explore the benefits of a novel drilling technique, ultrasonically-assisted drilling (UAD), and its possible utilization in orthopaedic surgeries. The study was performed by conducting experiments to understand the basic mechanics of the drilling process using high speed filming of the drilling zone followed by measurements to quantify thrust force, surface roughness and cracking of the bone near the immediate vicinity of the hole with and without ultrasonic assistance. Compared to the spiral chips produced during conventional drilling (CD), UAD was found to break the chips in small pieces which facilitated their fast evacuation from the cutting region. In UAD, lower drilling force and better surface roughness was measured in drilling in the radial and longitudinal axis of the bone. UAD produced crack-free holes which will enhance postoperative performance of fixative devices anchoring the bone. UAD may be used as a possible substitute for CD in orthopaedic clinics.

Computational models to determine fluiddynamical transients due to condensation induced water hammer (CIWH)

International Nuclear Information System (INIS)

Swidersky, Harald; Schaffrath, Andreas; Dudlik, Andreas

2012-01-01

Condensation induced water hammer ('condensation hammer', CIWH) represent a dangerous phenomenon in pipings, which can endanger the pipe integrity. If they cannot be excluded, they have to be taken into account for the integrity proof of components and pipe structures. Up to now, there exists no substantiated model, which sufficiently determines loads due to CIWH. Within the framework of the research alliance CIWA, a tool for estimating the potential and the amount of pressure loads will be developed based on theoretical work and supported by experimental results. This first study discusses used computational models, results of experimental observations and gives an outlook onto future techniques. (orig.)

Development plan for an advanced drilling system with real-time diagnostics (Diagnostics-While-Drilling)

Energy Technology Data Exchange (ETDEWEB)

FINGER,JOHN T.; MANSURE,ARTHUR J.; PRAIRIE,MICHAEL R.; GLOWKA,D.A.

2000-02-01

This proposal provides the rationale for an advanced system called Diagnostics-while-drilling (DWD) and describes its benefits, preliminary configuration, and essential characteristics. The central concept is a closed data circuit in which downhole sensors collect information and send it to the surface via a high-speed data link, where it is combined with surface measurements and processed through drilling advisory software. The driller then uses this information to adjust the drilling process, sending control signals back downhole with real-time knowledge of their effects on performance. The report presents background of related previous work, and defines a Program Plan for US Department of Energy (DOE), university, and industry cooperation.

Development of vertical drilling apparatus (Terra-Drill); Entwicklung eines Vertikal-Bohrgeraets (Terra-Drill) - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Jenne, D.

2009-05-15

This well-illustrated final report for the Swiss Federal Office of Energy (SFOE) reports on the development of a vertical drilling apparatus named Terra-Drill. The various stages of the development of the apparatus, which is based on earlier designs, is discussed. New norms issued in Germany for the size of boreholes for buried vertical heat-exchangers and the appropriate linings to be used are discussed. The new Terra Drill 4407 V drilling apparatus and its testing are discussed. The drill is quoted as being particularly suitable for cramped locations. Technical details are presented and a comprehensive collection of photographs is included. Various preliminary reports and development documentation are included.

Taking aim : particle impact drilling targets ROP gains

Energy Technology Data Exchange (ETDEWEB)

Mahoney, J.

2005-11-01

Details of a new drilling technique developed by Particle Drilling Technologies Inc. were presented. Particle impact drilling uses buckshot-like steel particles entrained with ordinary drilling mud that are accelerated through a specially-designed drill bit to bombard hard-rock formations at rapid-fire velocities of up to 4 million times a minute. Conventional drill bits rely on mechanical energy from some 50,000 pounds of weight on bit and torque to break or fracture the formation, whereas particle impact drilling relies on hydraulic energy to blast the steel particles from the bit's jetting nozzles in order to repeatedly fracture the formation. It was suggested that the new technology will accelerate the drilling process. Tests have shown that the new device out-performs conventional bits in hard formations by utilizing the hydraulics of the rig to drill with particles. In field tests, drilling was 4 times faster than conventional methods. It was anticipated that the bit will be up to 150 per cent faster in softer rock formations. In order to avoid clogging, the system uses a shot trap to remove the steel balls, which are roughly one-tenth of an inch in diameter, from the drilling fluid before it enters the shale shaker. The shot is recycled after each well. During drilling, mud circulation must be continuous for the system to work. If the system can't circulate cleanly out of a hole, there is a disruption in the process and drilling fluid may move up the annulus at 350 feet per minute when it leaves bottomhole. It was suggested that circulation issues can be resolved by increasing mud viscosity. A less than optimal performance during a recent test at Catoosa was attributed to a lack of control over drilling fluid parameters and to the use of an overly-large well casing. It was concluded that the new system will likely greatly reduce the number of days it takes to drill a well. 2 figs.

Surface Modification of AISI 440B Stainless Steel and its Influence on Surgical Drill Bits Performance

Directory of Open Access Journals (Sweden)

Łępicka M.

2016-09-01

Full Text Available The development of modern invasive surgery is highly dependent on the performance of surgical instruments, understood as long-term efficiency arising from high resistance to wear and corrosion. In order to maintain sufficient reliability, surgical cutting instruments are often made of martensitic stainless steels. Nevertheless, the use of ferrous alloys in medical applications is still a concern due to their questionable corrosion and wear resistance. To extend their biocompatibility, improve stability in variable environmental conditions, improve ease of handling, and maximize their performance, diffusion layers and coatings are applied to the surface. The aim of this work was to evaluate the effect of TiN and diamond-like carbon (DLC surface modification on the performance of surgical drill bits, that is, wear and corrosion resistance, measured in model and field tests. Based on the findings presented, DLC layers can be recommended as anti-wear and anti-corrosion coatings for surgical drill bits.

Method for estimating steam hammer effects on swing-check valves during closure

International Nuclear Information System (INIS)

Uram, E.M.

1976-01-01

Relationships are developed for estimating the disk impact velocity resulting from a free swing closure of swing-check valves in normal flow and for pipe rupture. They derive from a phase-plane solution of the differential equation for the disk motion that accounts for the nature of the valve pressure drop variation due to steam-hammer effects during closure. For closure in normal flow, the method presented has a more correct foundation than that given in reference where a constant, average valve pressure differential based upon the steady-state pressure drop for the total piping system (which has no real relationship to the steam-hammer-induced valve pressure changes during the closure transient) is used in the valve disk motion equation

Stratified flow instability and slug formation leading to condensation-induced water hammer in a horizontal refrigerant pipe

International Nuclear Information System (INIS)

Samuel Martin, C.

2005-01-01

Full text of publication follows: An experimental apparatus was designed for the purpose of investigating the phenomenon of condensation-induced water hammer in an ammonia refrigeration system. Water hammer was initiated by introducing warm ammonia gas over static subcooled ammonia liquid placed in a horizontal 146.3 mm diameter carbon steel pipe 6.0 m in length. By means of fast response piezoelectric pressure transducers and a high speed data acquisition system rapid dynamic pressures were recorded whenever a shock event occurred. Moreover, by means of top-mounted diaphragm pressure transducers the speed of liquid slugs propagating along the pipe was determined. The occurrence of condensation induced water hammer depended upon three major variables; namely, (1) initial liquid depth, (2) liquid temperature, and (3) mass flow rate of warm gas. For given liquid depth and temperature, once the warm gas threshold conditions were exceeded shocks occurred with greater magnitude as the mass flow rate of gas input was increased. With adequate subcooling condensation-induced water hammer occurred for initial liquid depths ranging from 25% to 95% of internal pipe diameter. The threshold mass flow rate of warm gas necessary to initiate water hammer was greater as the initial liquid depth was lowered. Based upon experimental results obtained from four pressure transducers located on the top of the test pipe conditions corresponding to bridging were ascertained. For various initial liquid depths the onset of instability from stratified flow to bridging was correlated with the Taitel-Dukler instability criterion. (author)

Potential dust exposures in underground mines of the former Wismut Ltd. during the early phase of uranium mining after the second world war

International Nuclear Information System (INIS)

Bauer, H.D.

1997-01-01

We performed dust measurements in several underground mines of Wismut Ltd. during dry drilling and ore mining with pneumatic hammers. The purpose was to reproduce operational conditions typical of the early phase of uranium mining after the second world war. Since do dust measurements were performed, data or information on exposures in that period of time are not available. Our investigations were intended to fill this gap. The decisive step to reduce exposures in mining areas and in regions to be opened up and prepared was the conversion from dry drilling with air flushing to wet drilling with water flushing resulting in a decrease of fine dust concentrations by more than 97%. (orig./SR) [de

Drilling bits for deep drilling and process for their manufacture

Energy Technology Data Exchange (ETDEWEB)

Rhode, H.; Juergens, R.; Feenstra, R.; Busking, B.E.

1978-11-30

The invention concerns a drilling head or a drilling bit for use in deep drilling in underground formations and particularly concerns a drilling bit with a drilling bit body, which has a shank and a hollow space, which is connected with a duct extending through the shank. The drilling bit body has several separate cutting elements for removing material from the floor of a borehole and hydraulic devices for cooling and/or cleaning the cutting elements are provided.

Computation of water hammer protection of modernized pumping station

Science.gov (United States)

Himr, Daniel

2014-03-01

Pumping station supplies water for irrigation. Maximal capacity 2 × 1.2m3·s-1 became insufficient, thus it was upgraded to 2 × 2m3·s-1. Paper is focused on design of protection against water hammer in case of sudden pumps trip. Numerical simulation of the most dangerous case (when pumps are giving the maximal flow rate) showed that existing air vessels were not able to protect the system and it would be necessary to add new vessels. Special care was paid to influence of their connection to the main pipeline, because the resistance of the connection has a significant impact on the scale of pressure pulsations. Finally, the pump trip was performed to verify if the system worked correctly. The test showed that pressure pulsations are lower (better) than computation predicted. This discrepancy was further analysed.

Influence of pin and hammer mill on grinding characteristics, thermal and antioxidant properties of coriander powder.

Science.gov (United States)

Barnwal, P; Singh, K K; Sharma, Alka; Choudhary, A K; Saxena, S N

2015-12-01

In present study, influence of grinding (hammer and pin mills) and moisture content (range: 6.4-13.6 % dry basis) on the quality traits of coriander powder were investigated. These include grinding parameters, colour parameters, specific heat, thermal conductivity, thermal diffusivity, glass transition temperature, essential oil, total phenolic content, total flavonoid content and DPPH scavenging (%) of coriander powder. For coriander seed, the geometric properties such as major, medium, minor dimensions, geometric mean diameter, arithmetic mean diameter, sphericity, surface area and volume of coriander seeds increased significantly with increasing moisture (6.4-13.6 % db). For coriander powder, the grinding parameters such as average particle size, volume surface mean diameter and volume mean diameter increased significantly with increasing moisture (6.4-13.6 % db). With the grinding method, the colour attributes of coriander powder such as L-value, a-value, b-value, hue angle and browning index varied significantly. It was observed that the specific heat followed second order polynomial relationship with temperature and moisture whereas thermal conductivity varied linearly with temperature and moisture content. The variation of glass transition temperature with moisture can be best represented in quadratic manner. Total flavonoid content (mg QE/g crude seed extract) and DPPH scavenging % activity of coriander powder is significantly affected by grinding methods. A lower value of specific heat was observed for hammer ground coriander powder as compared to pin mill ground coriander powder. The thermal conductivity of hammer mill ground coriander powder was higher as compared to pin mill ground coriander. It was observed that hammer mill yields more fine coriander powder in comparison to pin mill. The browning index was more in hammer mill ground coriander powder.

Utilization of the Nelkin model in a Hammer computer code for calculation the reactor parameters

International Nuclear Information System (INIS)

Leal, L.C.

1980-07-01

The possibility of modifying the HAMMER code, in the thermal part, by changing the thermal neutron scattering Kernel of its library for another one calculated in a subprogramm which can be incorporated to the code, is studied. This subprogramm uses the original version of the Nelkin model instead of its approximation which is used in the HAMMER. It has the advantage of giving the values of the Kernel for any temperature of the reactor for the approximations P 0 , P 1 , P 2 and P 3 . (Author) [pt

Helium hammer in superfluid transfer

Science.gov (United States)

Tward, E.; Mason, P. V.

1984-01-01

Large transient pressure pulses, referred to as a helium hammer, which occurred in the transfer line of the main cryogenic tank during the development tests of the Infrared Astronomical Satellite, launched on January 25, 1983, are analyzed, and the measures taken to prevent a failure described. The modifications include an installation of a 2.3-liter surge tank upstream, and a back-up relief valve downstream, of a burst disk. The surge tank is designed to attenuate a 0.33-MPa pressure pulse at the inlet down to 0.092 MPa at the outlet. A mechanism of the pulse generation is suggested, which involves flashing and rapid recondensation of the small amount of liquid entering the warm section of a transition to room temperature.

Testing as a service with HammerCloud

International Nuclear Information System (INIS)

Llamas, Ramón Medrano; Barrand, Quentin; Sciabà, Andrea; Ster, Daniel van der; Elmsheuser, Johannes; Legger, Federica; Sciacca, Gianfranco

2014-01-01

HammerCloud was designed and born under the needs of the grid community to test the resources and automate operations from a user perspective. The recent developments in the IT space propose a shift to the software defined data centres, in which every layer of the infrastructure can be offered as a service. Testing and monitoring is an integral part of the development, validation and operations of big systems, like the grid. This area is not escaping the paradigm shift and we are starting to perceive as natural the Testing as a Service (TaaS) offerings, which allow testing any infrastructure service, such as the Infrastructure as a Service (IaaS) platforms being deployed in many grid sites, both from the functional and stressing perspectives. This work will review the recent developments in HammerCloud and its evolution to a TaaS conception, in particular its deployment on the Agile Infrastructure platform at CERN and the testing of many IaaS providers across Europe in the context of experiment requirements. The first section will review the architectural changes that a service running in the cloud needs, such an orchestration service or new storage requirements in order to provide functional and stress testing. The second section will review the first tests of infrastructure providers on the perspective of the challenges discovered from the architectural point of view. Finally, the third section will evaluate future requirements of scalability and features to increase testing productivity.

A four-equation friction model for water hammer calculation in quasi-rigid pipelines

International Nuclear Information System (INIS)

Ghodhbani, Abdelaziz; Haj Taïeb, Ezzeddine

2017-01-01

Friction coupling affects water hammer evolution in pipelines according to the initial flow regime. Unsteady friction models are only validated with uncoupled formulation. On the other hand, coupled models such as four-equation model, provide more accurate prediction of water hammer since fluid-structure interaction (FSI) is taken into account, but they are limited to steady-state friction formulation. This paper deals with the creation of the “four-equation friction model” which is based on the incorporation of the unsteady head loss given by an unsteady friction model into the four-equation model. For transient laminar flow cases, the Zielke model is considered. The proposed model is applied to a quasi-rigid pipe with axial moving valve, and then calculated by the method of characteristics (MOC). Damping and shape of the numerical solution are in good agreement with experimental data. Thus, the proposed model can be incorporated into a new computer code. - Highlights: • Both Zielke model and four-equation model are insufficient to predict water hammer. • The four-equation friction model proposed is obtained by incorporating the unsteady head loss in the four-equation model. • The solution obtained by the proposed model is in good agreement with experimental data. • The wave-speed adjustment scheme is more efficient than interpolations schemes.

Results from Testing of Two Rotary Percussive Drilling Systems

Science.gov (United States)

Kriechbaum, Kristopher; Brown, Kyle; Cady, Ian; von der Heydt, Max; Klein, Kerry; Kulczycki, Eric; Okon, Avi

2010-01-01

The developmental test program for the MSL (Mars Science Laboratory) rotary percussive drill examined the e ect of various drill input parameters on the drill pene- tration rate. Some of the input parameters tested were drill angle with respect to gravity and percussive impact energy. The suite of rocks tested ranged from a high strength basalt to soft Kaolinite clay. We developed a hole start routine to reduce high sideloads from bit walk. The ongoing development test program for the IMSAH (Integrated Mars Sample Acquisition and Handling) rotary percussive corer uses many of the same rocks as the MSL suite. An additional performance parameter is core integrity. The MSL development test drill and the IMSAH test drill use similar hardware to provide rotation and percussion. However, the MSL test drill uses external stabilizers, while the IMSAH test drill does not have external stabilization. In addition the IMSAH drill is a core drill, while the MSL drill uses a solid powdering bit. Results from the testing of these two related drilling systems is examined.

Environment-friendly drilling operation technology

Science.gov (United States)

Luo, Huaidong; Jing, Ning; Zhang, Yanna; Huang, Hongjun; Wei, Jun

2017-01-01

Under the circumstance that international safety and environmental standards being more and more stringent, drilling engineering is facing unprecedented challenges, the extensive traditional process flow is no longer accepted, the new safe and environment-friendly process is more suitable to the healthy development of the industry. In 2015, CNPCIC adopted environment-friendly drilling technology for the first time in the Chad region, ensured the safety of well control, at the same time increased the environmental protection measure, reduced the risk of environmental pollution what obtain the ratification from local government. This technology carries out recovery and disposal of crude oil, cuttings and mud without falling on the ground. The final products are used in road and well site construction, which realizes the reutilization of drilling waste, reduces the operating cost, and provides a strong technical support for cost-cutting and performance-increase of drilling engineering under low oil price.

Experimental Analysis of Temperature Differences During Implant Site Preparation: Continuous Drilling Technique Versus Intermittent Drilling Technique.

Science.gov (United States)

Di Fiore, Adolfo; Sivolella, Stefano; Stocco, Elena; Favero, Vittorio; Stellini, Edoardo

2018-02-01

Implant site preparation through drilling procedures may cause bone thermonecrosis. The aim of this in vitro study was to evaluate, using a thermal probe, overheating at implant sites during osteotomies through 2 different drilling methods (continuous drilling technique versus intermittent drilling technique) using irrigation at different temperatures. Five implant sites 13 mm in length were performed on 16 blocks (fresh bovine ribs), for a total of 80 implant sites. The PT-100 thermal probe was positioned 5 mm from each site. Two physiological refrigerant solutions were used: one at 23.7°C and one at 6.0°C. Four experimental groups were considered: group A (continuous drilling with physiological solution at 23.7°C), group B (intermittent drilling with physiological solution at 23.7°C), group C (continuous drilling with physiological solution at 6.0°C), and group D (intermittent drilling with physiological solution at 6.0°C). The Wilcoxon rank-sum test (2-tailed) was used to compare groups. While there was no difference between group A and group B (W = 86; P = .45), statistically significant differences were observed between experimental groups A and C (W = 0; P =.0001), B and D (W = 45; P =.0005), and C and D (W = 41; P = .003). Implant site preparation did not affect the overheating of the bone. Statistically significant differences were found with the refrigerant solutions. Using both irrigating solutions, bone temperature did not exceed 47°C.

Computational simulations of direct contact condensation as the driving force for water hammer

International Nuclear Information System (INIS)

Ceuca, Sabin-Cristian

2015-01-01

An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

Computational simulations of direct contact condensation as the driving force for water hammer

Energy Technology Data Exchange (ETDEWEB)

Ceuca, Sabin-Cristian

2015-04-27

An analysis, based on Computer Simulations of the Direct Contact Condensation as the Driving Force for the Condensation Induced Water Hammer phenomenon is performed within this thesis. The goal of the work is to develop a mechanistic HTC model, with predictive capabilities for the simulation of horizontal or nearly horizontal two-phase ows with complex patterns including the e ect of interfacial heat and mass transfer. The newly developed HTC model was implemented into the system code ATHLET and into the CFD tools ANSYS CFX and OpenFOAM. Validation calculations have been performed for horizontal or nearly horizontal ows, where simulation results have been compared against the local measurement data such as void and temperature or area averaged data delivered by a wire mesh sensor.

Performance evaluation of vegetable-based oils in drilling austenitic stainless steel

DEFF Research Database (Denmark)

Belluco, Walter; De Chiffre, Leonardo

2004-01-01

breaking were recorded for each bore, and tool wear was measured at constant intervals. A commercial mineral-based oil was taken as reference product, and five vegetable-based cutting fluids at different levels of additivation were tested. All measured parameters were in agreement, confirming......The efficiency of six cutting oils was evaluated in drilling AISI 316L austenitic stainless steel using conventional HSS-Co tools by measurements of tool life, tool wear, cutting forces and chip formation. Seven tools were tested with each fluid to catastrophic failure. Cutting forces and chip...... to tool life testing. All vegetable-based fluids performed better than the reference product. The best performance was obtained with a cutting fluid yielding 177% increases in tool life and 7% reduction in thrust force. (C) 2003 Elsevier B.V. All rights reserved....

CASING DRILLING TECHNOLOGY

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

2005-12-01

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.

HIGH-POWER TURBODRILL AND DRILL BIT FOR DRILLING WITH COILED TUBING

Energy Technology Data Exchange (ETDEWEB)

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

2008-03-31

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

Usefulness of temporal bone prototype for drilling training: A prospective study.

Science.gov (United States)

Aussedat, C; Venail, F; Nguyen, Y; Lescanne, E; Marx, M; Bakhos, D

2017-12-01

Dissection of cadaveric temporal bones (TBs) is considered the gold standard for surgical training in otology. For many reasons, access to the anatomical laboratory and cadaveric TBs is difficult for some facilities. The aim of this prospective and comparative study was to evaluate the usefulness of a physical TB prototype for drilling training in residency. Prospective study. Tertiary referral centre. Thirty-four residents were included. Seventeen residents (mean age 26.7±1.6) drilled on only cadaveric TBs ("traditional" group), in the traditional training method, while seventeen residents (mean age 26.5±1.7) drilled first on a prototype and then on a cadaveric TB ("prototype" group). Drilling performance was assessed using a validated scale. Residents completed a mastoid image before and after each drilling to enable evaluation of mental representations of the mastoidectomy. No differences were observed between the groups with respect to age, drilling experience and level of residency. Regarding drilling performance, we found a significant difference across the groups, with a better score in the prototype group (P=.0007). For mental representation, the score was statistically improved (P=.0003) after drilling in both groups, suggesting that TB drilling improves the mental representation of the mastoidectomy whether prototype or cadaveric TB is used. The TB prototype improves the drilling performance and mental representation of the mastoidectomy in the young resident population. A drilling simulation with virtual or physical systems seems to be a beneficial tool to improve TB drilling. © 2017 John Wiley & Sons Ltd.

Analysis of mixed oxides critical experiments using the Hammer-Technion code with self-shielding treatment by Bondarenko method

International Nuclear Information System (INIS)

Abe, Alfredo Y.; Santos, Adimir dos

1995-01-01

The present work summarizes the verification of the treatment of self-shielding based on Bondarenko method in HAMMER-TECHNION cell code for the Pu O 2 -U O 2 critical system using JENDL-3 nuclear data library. The results obtained are in excellent agreement with the original treatment of self-shielding employed by HAMMER-TECHNION cell code. (author). 9 refs, 1 fig, 9 tabs

Drilling unit

Energy Technology Data Exchange (ETDEWEB)

Umanchik, N P; Demin, A V; Khrustalev, N N; Linnik, G N; Lovchev, S V; Rozin, M M; Sidorov, R V; Sokolov, S I; Tsaregradskiy, Yu P

1981-01-01

A drilling unit is proposed which includes a hydraulic lifter, hydraulic multiple-cylinder pump with valve distribution and sectional drilling pump with separators of the working and flushing fluid. In order to reduce metal consumption and the overall dimensions of the drilling unit, the working cavity of each cylinder of the hydraulic multiple-cylinder pump is equipped with suction and injection valves and is hydraulically connected to the working cavity by one of the sections of the drilling pump.

Technology strategy for cost-effective drilling and intervention; Technology Target Areas; TTA4 - Cost effective drilling and intervention

Energy Technology Data Exchange (ETDEWEB)

2007-07-01

The main goals of the OG21 initiative are to (1) develop new technology and knowledge to increase the value creation of Norwegian oil and gas resources and (2) enhance the export of Norwegian oil and gas technology. The OG21 Cost-effective Drilling and Intervention (CEDI) Technology Target Area (TTA) has identified some key strategic drilling and well intervention needs to help meet the goals of OG21. These key strategic drilling and well intervention needs are based on a review of present and anticipated future offshore-Norway drilling and well intervention conditions and the Norwegian drilling and well intervention industry. A gap analysis has been performed to assess the extent to which current drilling and well intervention research and development and other activities will meet the key strategic needs. Based on the identified strategic drilling and well intervention needs and the current industry res each and development and other activities, the most important technology areas for meeting the OG21 goals are: environment-friendly and low-cost exploration wells; low-cost methods for well intervention/sidetracks; faster and extended-reach drilling; deep water drilling, completion and intervention; offshore automated drilling; subsea and sub-ice drilling; drilling through basalt and tight carbonates; drilling and completion in salt formation. More specific goals for each area: reduce cost of exploration wells by 50%; reduce cost for well intervention/sidetracks by 50%; increase drilling efficiency by 40%; reduce drilling cost in deep water by 40 %; enable offshore automated drilling before 2012; enable automated drilling from seabed in 2020. Particular focus should be placed on developing new technology for low-cost exploration wells to stem the downward trends in the number of exploration wells drilled and the volume of discovered resources. The CEDI TTA has the following additional recommendations: The perceived gaps in addressing the key strategic drilling and

Study on Monitoring Rock Burst through Drill Pipe Torque

Directory of Open Access Journals (Sweden)

Zhonghua Li

2015-01-01

Full Text Available This paper presents a new method to identify the danger of rock burst from the response of drill pipe torque during drilling process to overcome many defects of the conventional volume of drilled coal rubble method. It is based on the relationship of rock burst with coal stress and coal strength. Through theoretic analysis, the change mechanism of drill pipe torque and the relationship of drill pipe torque with coal stress, coal strength, and drilling speed are investigated. In light of the analysis, a new device for testing drill pipe torque is developed and a series of experiments is performed under different conditions; the results show that drill pipe torque linearly increases with the increase of coal stress and coal strength; the faster the drilling speed, the larger the drill pipe torque, and vice versa. When monitoring rock burst by drill pipe torque method, the index of rock burst is regarded as a function in which coal stress index and coal strength index are principal variables. The results are important for the forecast of rock burst in coal mine.

Accuracy of linear drilling in temporal bone using drill press system for minimally invasive cochlear implantation.

Science.gov (United States)

Dillon, Neal P; Balachandran, Ramya; Labadie, Robert F

2016-03-01

A minimally invasive approach for cochlear implantation involves drilling a narrow linear path through the temporal bone from the skull surface directly to the cochlea for insertion of the electrode array without the need for an invasive mastoidectomy. Potential drill positioning errors must be accounted for to predict the effectiveness and safety of the procedure. The drilling accuracy of a system used for this procedure was evaluated in bone surrogate material under a range of clinically relevant parameters. Additional experiments were performed to isolate the error at various points along the path to better understand why deflections occur. An experimental setup to precisely position the drill press over a target was used. Custom bone surrogate test blocks were manufactured to resemble the mastoid region of the temporal bone. The drilling error was measured by creating divots in plastic sheets before and after drilling and using a microscope to localize the divots. The drilling error was within the tolerance needed to avoid vital structures and ensure accurate placement of the electrode; however, some parameter sets yielded errors that may impact the effectiveness of the procedure when combined with other error sources. The error increases when the lateral stage of the path terminates in an air cell and when the guide bushings are positioned further from the skull surface. At contact points due to air cells along the trajectory, higher errors were found for impact angles of [Formula: see text] and higher as well as longer cantilevered drill lengths. The results of these experiments can be used to define more accurate and safe drill trajectories for this minimally invasive surgical procedure.

Sandia's Geothermal Advanced Drill Rig Instrumentation Assists Critical Oil and Gas Drilling Operation

International Nuclear Information System (INIS)

Staller, George E.; Whitlow, Gary

1999-01-01

about 30 days. Several other Sandia instruments being developed for geothermal drilling are also being evaluated during this operation, Successful performance of these instruments on this important drilling job will reinforce our efforts to commercialize this technology for the geothermal and oil and gas drilling industries. Sandia's Rolling Float Meter was developed through the Lost Circulation Technology Program sponsored by the U. S. Department of Energy, Office of Geothermal Technologies. It monitors drilling fluid returns to rapidly detect loss of circulation during geothermal drilling. Lost circulation is particularly prevalent in geothermal wells, and can add as much as 10% to the total cost of drilling the well. Consequently, rapid detection and treatment of lost circulation is necessary for cost- effective geothermal drilling. Sandia has been evaluating and demonstrating the capabilities of the RFM to the geothermal industry for several years. In addition to lost circulation, the RFM is also useful for accurately detecting well kicks. Contacts have been made with mud logging companies that are involved with both geothermal and oil and gas drilling operations

Changing the fundamentals[Drill technology

Energy Technology Data Exchange (ETDEWEB)

Flatern, R. von

2003-02-01

Evolution of the science of drilling oil and gas wells has evolved in fits and starts. From drilling with cables to rotary tables to top drives, from straight holes to horizontal, it has been a process interrupted occasionally by flashes of revolutionary brilliance. In this article the author looks at the state of just a few of the technologies that define or threaten to change how drillers go about their business. In the early days of deepwater exploration drillers responded more to technical challenges than financial ones, primarily with immense semisubmersibles and drillships, together with all he necessary ancillary items. The goal of getting deeper faster is not a new one, better performance bits, muds, LWD and MWD, together with numerous other developments all emerged as a result of the desire to shorten the time between spud and TD. But whereas saving a day or two drilling onshore or nearshore is desirable, it has never before been possible to realize the kind of substantial financial benefits from relatively small time savings. Research and development into these type of savings with the design and improvement of different types drill bits and casing drilling is described.

On the prediction of impact noise, V: The noise from drop hammers

Science.gov (United States)

Richards, E. J.; Carr, I.; Westcott, M.

1983-06-01

In earlier papers in this series, the concepts of "acceleration" and "ringing" noise have been studied in relation to impact machines, and values of radiation efficiency have been obtained for the various types of structural components. In the work reported in this paper the predicted and measured noise radiation from a drop hammer, both in full-scale and in {1}/{3}- scale model form, were examined. It is found that overall noise levels ( Leq per event) can be predicted from vibration measurements to within ± 1·5 dB, and to within ±2·5 dB in one-third octave bands. In turn this has permitted noise reduction techniques to be examined by studies of local component vibration levels rather than overall noise, a method which provides considerable enlightenment at the design stage. It is shown that on one particular drop hammer, the noise energy is shared surprisingly uniformly over four or five sources, and that when these have been reduced, the overall noise reduction is severely limited by the "acceleration" noise from the "tup" or "hammer" itself. As this is difficult to eliminate without a basic change in forging technology, it follows that "tup" enclosure or modification of the sharpness of the final "hard" impact are the only means available for any serious noise reduction. Also indicated is the reliability of using model techniques, suitably scaled in frequency and impulse magnitude, in developing machinery with impact characteristics.

Hard rock star : Weatherford's multiphase performance drilling system increases penetration rates in hard, abrasive formations

Energy Technology Data Exchange (ETDEWEB)

Smith, M.

2010-12-15

This article described Weatherford's Multiphase Performance Drilling (MPPD) system that enhances drilling rate penetration. The technology was awarded the 2010 winner for best drilling technology for a company with 100 employees or more. Weatherford Canada and Suncor Energy developed the patent-pending MPPD system in the Panther field, and have expanded its use to Suncor's Kelly Lake and Gwillim plays in British Columbia. The new technology is ready to be launched worldwide. This article discussed the MPPD system, with particular reference to its benefits; process; cost savings; and technology utilization. The technique is ideal for drilling in harsh, abrasive formations such as the Nikanassin or Cadomin. It has allowed Suncor to save as much as $1.5 million per well. The article also noted that the key to the process is the controlled use of nitrogen to lighten mud weight. Weatherford used its model 7000 rotating control device to provide precise control of the wellbore pressure profile. It was concluded that Weatherford had significant praise for its partner in developing the MPPD system since its inception with Suncor in 2004, particularly since few client companies have the patience and the willingness to make expensive long-term investment necessary to perfect such systems. 2 figs.

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

Energy Technology Data Exchange (ETDEWEB)

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)

2008-07-01

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)

Comparison between UMSICHT water hammer experiments and calculations using RELAP5/MOD3.3

International Nuclear Information System (INIS)

Messing, Ralf

2008-01-01

Water hammer phenomena regularly occur in piping systems of nuclear power plants, e.g. after the rapid closure of valves. As the loads are usually several times higher than during normal operation pipe rupture is possible and therefore the integrity of the nuclear power plant can be endangered. In recent years extensive studies have been performed to assess the capabilities of the widely-used transient thermohydraulic system codes like RELAP5 for the simulation of water hammers and pressure surges in piping systems. The parameters affecting the results of such simulations are on the one side related to the numerical method, in particular the grid step size Δx and time step size Δt, and on the other hand to the models for present physical effects like the fluid-structure-interaction (FSI), unsteady friction or the release of dissolved air. In many studies experimental data obtained at the Fraunhofer Institute UMSICHT at Oberhausen/Germany has been used for code validation. In a vast campaign reliable data has been measured under varying boundary conditions for pressure surges in a pipe after a fast valve closure. Details of the experimental set-up are described in /1/ and /2/. Tiselj and Petelin /3/ provided theoretical background on the properties of the numerical scheme used by RELAP5 and Tiselj and Cerne /4/ highlighted the behavior at very small time steps. Kaliatka and al. /5/ investigated the influence of the grid step size and the time step size in RELAP5 on pressure transients obtained in UMSICHT experiments. Neuhaus and Dudlik /2/,/6/ studied the effects of fluidstructure- interaction, unsteady friction and degassing of dissolved air in tape-water filled pipes on pressure surges. They compared their numerical results again with experimental data from the UMSICHT test facility and observed a significant impact of all three parameters on the pressure-surge amplitudes and frequency. Barten and al. /15/ performed calculations of experiment 329 of the UMSICHT

Quality assurance for hammer forgings

International Nuclear Information System (INIS)

Potthast, E.

1984-01-01

The quality assurance program introduced by Arbed Saarstahl and laid down in a quality assurance manual is described. A particular attention is attached thereby both to quality practice proper and to a reliable flow of information amongst all the persons involved. The production and test sequence schedules of the hammer forging plant are illustrated by the example of a forged valve housing for nuclear power plants. These schedules specify not only the forging process in the individual production stages but also the workpiece contour after each working operation, the heat treatment, the furnace charging, and the inspection of finished parts. The formalization of the tests is designed both to promote the customer's trust towards the supplier and to prevent the formal operations involved from hindering further technical development. (orig.) [de

Numerical simulation of water hammer in low pressurized pipe: comparison of SimHydraulics and Lax-Wendroff method with experiment

Science.gov (United States)

Himr, D.

2013-04-01

Article describes simulation of unsteady flow during water hammer with two programs, which use different numerical approaches to solve ordinary one dimensional differential equations describing the dynamics of hydraulic elements and pipes. First one is Matlab-Simulink-SimHydraulics, which is a commercial software developed to solve the dynamics of general hydraulic systems. It defines them with block elements. The other software is called HYDRA and it is based on the Lax-Wendrff numerical method, which serves as a tool to solve the momentum and continuity equations. This program was developed in Matlab by Brno University of Technology. Experimental measurements were performed on a simple test rig, which consists of an elastic pipe with strong damping connecting two reservoirs. Water hammer is induced with fast closing the valve. Physical properties of liquid and pipe elasticity parameters were considered in both simulations, which are in very good agreement and differences in comparison with experimental data are minimal.

Numerical simulation of water hammer in low pressurized pipe: comparison of SimHydraulics and Lax-Wendroff method with experiment

Directory of Open Access Journals (Sweden)

Himr D.

2013-04-01

Full Text Available Article describes simulation of unsteady flow during water hammer with two programs, which use different numerical approaches to solve ordinary one dimensional differential equations describing the dynamics of hydraulic elements and pipes. First one is Matlab-Simulink-SimHydraulics, which is a commercial software developed to solve the dynamics of general hydraulic systems. It defines them with block elements. The other software is called HYDRA and it is based on the Lax-Wendrff numerical method, which serves as a tool to solve the momentum and continuity equations. This program was developed in Matlab by Brno University of Technology. Experimental measurements were performed on a simple test rig, which consists of an elastic pipe with strong damping connecting two reservoirs. Water hammer is induced with fast closing the valve. Physical properties of liquid and pipe elasticity parameters were considered in both simulations, which are in very good agreement and differences in comparison with experimental data are minimal.

Multi-sensor measurement system for robotic drilling

OpenAIRE

Frommknecht, Andreas; Kühnle, Jens; Pidan, Sergej; Effenberger, Ira

2015-01-01

A multi-sensor measurement system for robotic drilling is presented. The system enables a robot to measure its 6D pose with respect to the work piece and to establish a reference coordinate system for drilling. The robot approaches the drill point and performs an orthogonal alignment with the work piece. Although the measurement systems are readily capable of achieving high position accuracy and low deviation to perpendicularity, experiments show that inaccuracies in the robot's 6D-pose and e...

Computer-Supplemented Structural Drill Practice Versus Computer-Supplemented Semantic Drill Practice by Beginning College German Students: A Comparative Experiment

Science.gov (United States)

1979-01-01

610p ,/ VERSU OLEV EV, COMPUTER-SUPPLEMENTED STRUCTURAL DRILL PRACTICE OVERSUS -0MPUTER-SUPPLEMENTED SEMANTIC DRILL PRACTICE BY BEGINNING COLLGE ...refine a student’s capabilities to do specific mental/or physical performance" (p. 26). The same statement of purpose would obviously apply if the terms

Uniaxial Compressive Strengths of Rocks Drilled at Gale Crater, Mars

Science.gov (United States)

Peters, G. H.; Carey, E. M.; Anderson, R. C.; Abbey, W. J.; Kinnett, R.; Watkins, J. A.; Schemel, M.; Lashore, M. O.; Chasek, M. D.; Green, W.; Beegle, L. W.; Vasavada, A. R.

2018-01-01

Measuring the physical properties of geological materials is important for understanding geologic history. Yet there has never been an instrument with the purpose of measuring mechanical properties of rocks sent to another planet. The Mars Science Laboratory (MSL) rover employs the Powder Acquisition Drill System (PADS), which provides direct mechanical interaction with Martian outcrops. While the objective of the drill system is not to make scientific measurements, the drill's performance is directly influenced by the mechanical properties of the rocks it drills into. We have developed a methodology that uses the drill to indicate the uniaxial compressive strengths of rocks through comparison with performance of an identically assembled drill system in terrestrial samples of comparable sedimentary class. During this investigation, we utilize engineering data collected on Mars to calculate the percussive energy needed to maintain a prescribed rate of penetration and correlate that to rock strength.

A new drilling method-Earthworm-like vibration drilling.

Science.gov (United States)

Wang, Peng; Ni, Hongjian; Wang, Ruihe

2018-01-01

The load transfer difficulty caused by borehole wall friction severely limits the penetration rate and extended-reach limit of complex structural wells. A new friction reduction technology termed "earthworm-like drilling" is proposed in this paper to improve the load transfer of complex structural wells. A mathematical model based on a "soft-string" model is developed and solved. The results show that earthworm-like drilling is more effective than single-point vibration drilling. The amplitude and frequency of the pulse pressure and the installation position of the shakers have a substantial impact on friction reduction and load transfer. An optimization model based on the projection gradient method is developed and used to optimize the position of three shakers in a horizontal well. The results verify the feasibility and advantages of earthworm-like drilling, and establish a solid theoretical foundation for its application in oil field drilling.

Parameters affecting mechanical and thermal responses in bone drilling: A review.

Science.gov (United States)

Lee, JuEun; Chavez, Craig L; Park, Joorok

2018-04-11

Surgical bone drilling is performed variously to correct bone fractures, install prosthetics, or for therapeutic treatment. The primary concern in bone drilling is to extract donor bone sections and create receiving holes without damaging the bone tissue either mechanically or thermally. We review current results from experimental and theoretical studies to investigate the parameters related to such effects. This leads to a comprehensive understanding of the mechanical and thermal aspects of bone drilling to reduce their unwanted complications. This review examines the important bone-drilling parameters of bone structure, drill-bit geometry, operating conditions, and material evacuation, and considers the current techniques used in bone drilling. We then analyze the associated mechanical and thermal effects and their contributions to bone-drilling performance. In this review, we identify a favorable range for each parameter to reduce unwanted complications due to mechanical or thermal effects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Water-hammer experiences in the startup and early operation of the Shearon Harris plant

International Nuclear Information System (INIS)

Casada, D.

1987-01-01

During the startup testing and initial operation of any power plant, systems undergo planned transients to confirm their ability to respond as designed. In addition to planned testing, unplanned transients infrequently occur as equipment is initially used. Some of both the planned and unplanned transients result in water-hammer events. Several water-hammer events experienced during preoperational testing, power ascension testing, and early operation of the Shearon Harris nuclear power plant are presented. The cause, effect, and corrective actions undertaken to prevent recurrence for each event discussed are provided. In addition, examples of preventive measures taken, based on industry experience accrued at other plants, to prevent a similar occurrence at Shearon Harris are discussed

In-vitro analysis of forces in conventional and ultrasonically assisted drilling of bone.

Science.gov (United States)

Alam, K; Hassan, Edris; Imran, Syed Husain; Khan, Mushtaq

2016-05-12

Drilling of bone is widely performed in orthopaedics for repair and reconstruction of bone. Current paper is focused on the efforts to minimize force generation during the drilling process. Ultrasonically Assisted Drilling (UAD) is a possible option to replace Conventional Drilling (CD) in bone surgical procedures. The purpose of this study was to investigate and analyze the effect of drilling parameters and ultrasonic parameters on the level of drilling thrust force in the presence of water irrigation. Drilling tests were performed on young bovine femoral bone using different parameters such as spindle speeds, feed rates, coolant flow rates, frequency and amplitudes of vibrations. The drilling force was significantly dropped with increase in drill rotation speed in both types of drilling. Increase in feed rate was more influential in raising the drilling force in CD compared to UAD. The force was significantly dropped when ultrasonic vibrations up to 10 kHz were imposed on the drill. The drill force was found to be unaffected by the range of amplitudes and the amount of water supplied to the drilling region in UAD. Low frequency vibrations with irrigation can be successfully used for safe and efficient drilling in bone.

Drilling reorganizes

Science.gov (United States)

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.

Author Details

African Journals Online (AJOL)

Akande, JM. Vol 15, No 2 (2015) - Articles Analysis of Button Bit Wear and Performance of Down-The-Hole Hammer Drill Abstract PDF. ISSN: 0855-210X. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of ...

Thermal numerical assessment of jawbone drilling factor during implantology

Directory of Open Access Journals (Sweden)

Adel Pirjamali Neisiani

2016-03-01

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.

Concrete density estimation by rebound hammer method

International Nuclear Information System (INIS)

Ismail, Mohamad Pauzi bin; Masenwat, Noor Azreen bin; Sani, Suhairy bin; Mohd, Shukri; Jefri, Muhamad Hafizie Bin; Abdullah, Mahadzir Bin; Isa, Nasharuddin bin; Mahmud, Mohamad Haniza bin

2016-01-01

Concrete is the most common and cheap material for radiation shielding. Compressive strength is the main parameter checked for determining concrete quality. However, for shielding purposes density is the parameter that needs to be considered. X- and -gamma radiations are effectively absorbed by a material with high atomic number and high density such as concrete. The high strength normally implies to higher density in concrete but this is not always true. This paper explains and discusses the correlation between rebound hammer testing and density for concrete containing hematite aggregates. A comparison is also made with normal concrete i.e. concrete containing crushed granite

Koolitamine : andmisrõõm või edevus? / Ants Vasar, Arne Kaasik, Hele Hammer

Index Scriptorium Estoniae

Vasar, Ants

2007-01-01

Küsimusele, miks olete hakanud ettevõtjana koolitajaks, vastavad ASi Viru Keskus juhatuse liige Ants Vasar, Columbus IT Partner Eesti ASi pertner ja nõukogu esimees Arne Kaasik ja Amserv Grupi finantsdirektor Hele Hammer

Impact of industrial hammer mill rotor speed on extraction efficiency and quality of extra virgin olive oil.

Science.gov (United States)

Polari, Juan J; Garcí-Aguirre, David; Olmo-García, Lucía; Carrasco-Pancorbo, Alegría; Wang, Selina C

2018-03-01

Crushing is a key step during olive oil extraction. Among commercial crushers, the hammer mill is the most widely used due to its robustness and high throughput. In the present work, the impact of hammer mill rotor speed on extraction yield and overall quality of super-high-density Arbosana olive oils were assessed in an industrial facility. Our results show that increasing the rotor speed from 2400rpm to 3600rpm led to a rise in oil yield of 1.2%, while conserving quality parameters. Sensory analysis showed more pungency with increased rotation speed, while others attributes were unaffected. Volatile compounds showed little variation with the differences in crusher speed; however, total phenols content, two relevant secoiridoids, and triterpenoids levels increased with rotor speed. Hammer mill rotor speed is a processing variable that can be tuned to increase the extraction efficiency and modulate the chemical composition of extra virgin olive oil. Copyright © 2017 Elsevier Ltd. All rights reserved.

Qualification of the new version of HAMMER computer code

International Nuclear Information System (INIS)

Chia, C.T.

1984-06-01

(HTEC) code were tested with a great number of diferent type of experiments. This experiments covers the most important parameters in neutronic calculations, such as the cell geometry and composition. The HTEC code results have been analysed and compared with experimental data and results given by the literature and simulated by HAMMER and LEOPARD codes. The quantities used for analysis were Keff and the following integral parameters: R28 - ratio of epicadmium-to-subcadmium 238 U captures; D25 - ratio of epicadmium-to-subcadmium 235 U fission; D28 - ratio of 238 U fissions to 235 U fissions; C - ratio of 238 U captures to 235 U fissions; RC02 - ratio of epicadmium-to-subcadmium 232 Th capture. The analysis shows that the results given by the code are in good agreement with the experimental data and the results given by the other codes. The calculation that have been done with the detailed ressonance profile tabulations of plutonium isotopes shows worst results than that obtained with the ressonance parameters. Almost all the simulated cases, shows that the HTEC results are closest to the experimental data than the HAMMER results, when one do not use the detailed ressonance profile tabulations of the plutonium isotopes. (Author) [pt

Avoiding water hammer/fluid transients in nuclear piping systems by controlled filling

International Nuclear Information System (INIS)

1991-01-01

A variety of geometries and operating procedures that lead to steam bubble collapse induced water hammers have been explored experimentally. Construction guidelines that will eliminate the problem at the design stage have been proposed and methods for predicting the pressure signatures proposed

Characterization of Under-Building Contamination at Rocky Flats Implementing Environmental-Measurement While Drilling Process with Horizontal Directional Drilling

International Nuclear Information System (INIS)

WILLIAMS, CECELIA V.; LOCKWOOD, GRANT J.; NORMANN, RANDY A.; LINDSAY, THOMAS

2001-01-01

Characterization is required on thirty-one buildings at Rocky Flats Environmental Technology Site (RFETS or the Site) with known or suspected under building contamination. The Site has teamed with Sandia National Laboratory (SNL) to deploy Environmental Measure-While-Drilling (EMWD) in conjunction with horizontal directional drilling (HDD) to characterize under building contamination and to evaluate the performance and applicability for future characterization efforts. The Environmental Measurement-While-Drilling-Gamma Ray Spectrometer (EMWD-GRS) system represents an innovative blend of new and existing technology that provides the capability of producing real-time environmental drill bit data during drilling operations. The project investigated two locations, Building 886 and Building 123. Building 886 is currently undergoing D and D activities. Building 123 was demolished in 1998; however, the slab is present with under building process waste lines and utilities. This report presents the results of the EMWD Gamma Ray Spectrometer logging of boreholes at these two sites. No gamma emitting contamination was detected at either location.(author)

Visual analysis and Schmidt rebound hammer test of Taj-ul-Masajid

Directory of Open Access Journals (Sweden)

A. Hussain

2017-09-01

Full Text Available Taj-ul-Masajid, literally, the crown among mosques is an embodiment of genius structural engineering located in the heart of Madhya Pradesh, Bhopal. A unique combination of the Mughal Architecture in complete stone masonry and modern day RCC work, it is a liaison between the past and the present of structural engineering. A wonder in its own right, the structure is often neglected by technicians and conservationalists alike, a satire on their ingenuity. Now, in a severely dilapidated condition, the structure is in pressing need of structural rehabilitation. The authors intend to perform in-situ Non-Destructive Testing & Evaluation (NDT&E of this structure and thereby suggest steps to better its present condition. As a first step, they’ve performed the visual analysis and Schmidt Rebound Hammer Test on the concrete portion of the structure which has been presented herein. The authors have also suggested a new approach for the verification of results obtained.

High Temperature 300°C Directional Drilling System

Energy Technology Data Exchange (ETDEWEB)

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)

2015-07-31

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

Some considerations on water-hammer and cavitation following the sudden closure of a check-valve

International Nuclear Information System (INIS)

Caumette, P.; Lott, M.

1987-01-01

The function of a no-return check-valve is to obturate a pipe when the current in it has a tendancy to revert: in normal operation the valve is maintained in open position by the flow and it closes, in case of flow-rate inversion, under the action of its own weight and of the hydrodynamic forces. At the precise time of closure, the stream most of the time is suddenly interrupted, which determines a water-hammer and the separation of a water column followed by other water-hammers. The authors analyze the movement of a swing check-valve before closure and the subsequent evolution of the fluid state

Surgical drill system and surgical drill bit to be used therein

NARCIS (Netherlands)

Margallo Balbas, E.; Wieringa, P.A.; French, P.J.; Lee, R.A.; Breedveld, P.

2007-01-01

Surgical drill system comprising a mechanical drill bit and means for imaging the vicinity of the drill bit tip, said means comprising: at least one optical fiber having a distal end and a proximal end, said distal end being located adjacent said drill bit tip, an optical processing unit, said

Polymer Drilling Fluid with Micron-Grade Cenosphere for Deep Coal Seam

Directory of Open Access Journals (Sweden)

Peng Xu

2015-01-01

Full Text Available Traditional shallow coal seam uses clean water, solid-free system, and foam system as drilling fluid, while they are not suitable for deep coal seam drilling due to mismatching density, insufficient bearing capacity, and poor reservoir protection effect. According to the existing problems of drilling fluid, micron-grade cenosphere with high bearing capacity and ultralow true density is selected as density regulator; it, together with polymer “XC + CMC” and some other auxiliary agents, is jointly used to build micron-grade polymer drilling fluid with cenosphere which is suitable for deep coal seam. Basic performance test shows that the drilling fluid has good rheological property, low filtration loss, good density adjustability, shear thinning, and thixotropy; besides, drilling fluid flow is in line with the power law rheological model. Compared with traditional drilling fluid, dispersion stability basically does not change within 26 h; settlement stability evaluated with two methods only shows a small amount of change; permeability recovery rate evaluated with Qinshui Basin deep coal seam core exceeds 80%. Polymer drilling fluid with cenosphere provides a new thought to solve the problem of drilling fluid density and pressure for deep coal seam drilling and also effectively improves the performance of reservoir protection ability.

Improved ATLAS HammerCloud Monitoring for local Site Administration

CERN Document Server

Boehler, Michael; The ATLAS collaboration; Hoenig, Friedrich; Legger, Federica; Sciacca, Francesco Giovanni; Mancinelli, Valentina

2015-01-01

Every day hundreds of tests are run on the Worldwide LHC Computing Grid for the ATLAS, and CMS experiments in order to evaluate the performance and reliability of the different computing sites. All this activity is steered, controlled, and monitored by the HammerCloud testing infrastructure. Sites with failing functionality tests are auto-excluded from the ATLAS computing grid, therefore it is essential to provide a detailed and well organized web interface for the local site administrators such that they can easily spot and promptly solve site issues. Additional functionality has been developed to extract and visualize the most relevant information. The site administrators can now be pointed easily to major site issues which lead to site blacklisting as well as possible minor issues that are usually not conspicuous enough to warrant the blacklisting of a specific site, but can still cause undesired effects such as a non-negligible job failure rate. This paper summarizes the different developments and optimiz...

Improved ATLAS HammerCloud Monitoring for local Site Administration

CERN Document Server

Boehler, Michael; The ATLAS collaboration; Hoenig, Friedrich; Legger, Federica

2015-01-01

Every day hundreds of tests are run on the Worldwide LHC Computing Grid for the ATLAS, CMS, and LHCb experiments in order to evaluate the performance and reliability of the different computing sites. All this activity is steered, controlled, and monitored by the HammerCloud testing infrastructure. Sites with failing functionality tests are auto-excluded from the ATLAS computing grid, therefore it is essential to provide a detailed and well organized web interface for the local site administrators such that they can easily spot and promptly solve site issues. Additional functionalities have been developed to extract and visualize the most relevant information. The site administrators can now be pointed easily to major site issues which lead to site blacklisting as well as possible minor issues that are usually not conspicuous enough to warrant the blacklisting of a specific site, but can still cause undesired effects such as a non-negligible job failure rate. This contribution summarizes the different developm...

HammerCloud: A Stress Testing System for Distributed Analysis

CERN Document Server

van der Ster, Daniel C; Ubeda Garcia, Mario; Paladin, Massimo

2011-01-01

Distributed analysis of LHC data is an I/O-intensive activity which places large demands on the internal network, storage, and local disks at remote computing facilities. Commissioning and maintaining a site to provide an efficient distributed analysis service is therefore a challenge which can be aided by tools to help evaluate a variety of infrastructure designs and configurations. HammerCloud (HC) is one such tool; it is a stress testing service which is used by central operations teams, regional coordinators, and local site admins to (a) submit arbitrary number of analysis jobs to a number of sites, (b) maintain at a steady-state a predefined number of jobs running at the sites under test, (c) produce web-based reports summarizing the efficiency and performance of the sites under test, and (d) present a web-interface for historical test results to both evaluate progress and compare sites. HC was built around the distributed analysis framework Ganga, exploiting its API for grid job management. HC has been ...

If I Had a Hammer: Technology in the Language Arts Classroom.

Science.gov (United States)

Jester, Richard

2002-01-01

Describes the computer as a hammer, a tool with unique qualities that allows people to perceive, manipulate, and express language in ways quite different from traditional media. Explores the tool of the multimedia presentation, a common use of technology in classrooms today. Describes a simple project with sixth graders that incorporates reading,…

Preliminary Research on Possibilities of Drilling Process Robotization

Science.gov (United States)

Pawel, Stefaniak; Jacek, Wodecki; Jakubiak, Janusz; Zimroz, Radoslaw

2017-12-01

Nowadays, drilling & blasting is crucial technique for deposit excavation using in hard rock mining. Unfortunately, such approach requires qualified staff to perform, and consequently there is a serious risk related to rock mechanics when using explosives. Negative influence of explosives usage on safety issues of underground mine is a main cause of mining demands related to elimination of people from production area. Other aspects worth taking into consideration are drilling precision according to drilling pattern, blasting effectiveness, improvement of drilling tool reliability etc. In the literature different drilling support solutions are well-known in terms of positioning support systems, anti-jamming systems or cavity detection systems. For many years, teleoperation of drilling process is also developed. Unfortunately, available technologies have so far not fully met the industries expectation in hard rock. Mine of the future is expected to incorporate robotic system instead of current approaches. In this paper we present preliminary research related to robotization of drilling process and possibilities of its application in underground mine condition. A test rig has been proposed. To simulate drilling process several key assumptions have been accepted. As a result, algorithms for automation of drilling process have been proposed and tested on the test rig. Experiences gathered so far underline that there is a need for further developing robotic system for drilling process.

Research on Impact Stress and Fatigue Simulation of a New Down-to-the-Hole Impactor Based on ANSYS

Science.gov (United States)

Wu, Tao; Wang, Wei; Yao, Aiguo; Li, Yongbo; He, Wangyong; Fei, Dongdong

2018-06-01

In the present work, a down-to-the-hole electric hammer driven by linear motor is reported for drilling engineering. It differs from the common hydraulic or pneumatic hammers in that it can be applied to some special occasions without circulating medium due to its independence of the drilling fluid. The impact stress caused by the reciprocating motion between stator and rotor and the fatigue damage in key components of linear motor are analyzed by the ANSYS Workbench software and 3D model. Based on simulation results, the hammer's structure is optimized by using special sliding bearing, increasing the wall thickness of key and multilayer buffer gasket. Fatigue life and coefficient issues of the new structure are dramatically improved. However buffer gasket reduces the impactor's energy, different bumper structure effect on life improving and energy loss have also been elaborated.

A new approach for evaluating water hammer including the initial state of pressurization of the installation and fluid

Directory of Open Access Journals (Sweden)

G. Kaless

2016-04-01

Full Text Available The water hammer phenomenon is well known since the 19th century, while its mathematical formulation, by means of differential equations, is due to works of researchers such us Allievi (1903 and others from the beginning of the 20th century. The equations found in the technical publications produce a strange water hammer when the initial condition is defined assuming an incompressible fluid and a rigid pipe. The correct solution requires solving the water hammer equations for the initial state. When the finite difference method is applied, the initial state is solved by means of a set of non-linear equations. A novel approach is proposed including the initial state of pressurization into the governing equations and hence simplifying the calculus of the initial conditions. Furthermore, a critical reading of the deduction of the equations is done pointing out conceptual inconsistencies and proposing corrections.

Offshore drilling effects in Brazilian SE marine sediments: a meta-analytical approach.

Science.gov (United States)

Dore, Marina Pereira; Farias, Cássia; Hamacher, Cláudia

2017-01-01

The exploration and production of oil and gas reserves often result to drill cutting accumulations on the seafloor adjacent to drill locations. In this study, the detection of drilling influence on marine sediments was performed by meta-analytical comparison between data from pre- and post-drilling surveys undertaken in offshore Campos Basin, southeast of Brazil. Besides this overall appraisal on the geochemical variables, a multivariate assessment, considering only the post-drilling data, was performed. Among the variables, fines content, carbonates, total organic carbon, barium, chromium, copper, iron, manganese, nickel, lead, vanadium, zinc, and total petroleum hydrocarbons, only barium, copper, and hydrocarbons were related to drilling impacts. In relation to the point of discharge, relative elevated levels in the post-drilling campaigns were observed preferentially up to 500 m in the northeast and southwest directions, associated to the Brazil Current-predominant direction. Other distributed concentrations in the surroundings seem to indicate the dilution and dispersion of drilling waste promoted by meteoceanographic factors.

Reduced abrasion drilling fluid

NARCIS (Netherlands)

2010-01-01

A reduced abrasion drilling fluid system and method of drilling a borehole by circulating the reduced abrasion drilling fluid through the borehole is disclosed. The reduced abrasion drilling fluid comprises a drilling fluid, a first additive and a weighting agent, wherein the weighting agent has a

Reduced abrasion drilling fluid

NARCIS (Netherlands)

2012-01-01

A reduced abrasion drilling fluid system and method of drilling a borehole by circulating the reduced abrasion drilling fluid through the borehole is disclosed. The reduced abrasion drilling fluid comprises a drilling fluid, a first additive and a weighting agent, wherein the weighting agent has a

Development of controlled drilling technology and measurement method in the borehole (Phase 1)

International Nuclear Information System (INIS)

Kiho, Kenzo; Shin, Koichi; Suzuki, Koichi; Miyakawa, Kimio; Okada, Tetsuji; Masuhara, Yasunobu; Igeta, Noriyuki; Kobayakawa, Hiroaki; Yamamoto, Shinya

2006-01-01

In Japan, the soft sedimentary rock of the Neogene tertiary is being focused as a host rock for High Level Waste (HLW) disposal. Especially, the soft sedimentary rock at the coastal area is thought to be one of the best candidates, since there is little driving force of the underground water. The measurement and logging of the bore hole in order to investigate the hydro-geological and geo-mechanical conditions of the host rock is a very important way to examine the potential of the disposal candidates. Central Research Institute of Electric Power Industry (CRIEPI) has been conducting the project on controlled drilling and the logging/measurement technologies in its boreholes. The key technologies of the project were defined as follows; (1) Drilling technology to bent the hole as intend. (2) Locality detection technology of the drill bit (MWD). (3) Core sampling technology to obtain the undisturbed rock core. (4) Logging and measurement technology during drilling. The drilling system and measuring system were integrated and systemized after each apparatus was manufactured and its performance was checked. The performance of the drilling system was checked to drill the artificial rock mass to the depth of 80 m before conducting in-situ drilling. The performance of the drilling and measurement systems were investigated to drill the mudstone of the Neogene Tertiary to the length of 547 m and to conduct the downhole measurement and logging in its borehole at the Horonobe site. Considering these performance testing, the flow diagram of the controlled drilling and measurement system was established. (author)

Test plan for sonic drilling at the Hanford Site in FY 1993

International Nuclear Information System (INIS)

McLellan, G.W.

1993-01-01

This test plan describes the field demonstration of the sonic drilling system being conducted as a coordinated effort between the VOC-Arid ID (Integrated Demonstration) and the 200 West Area Carbon Tetrachloride ERA (Expedited Response Action) programs at Hanford. The purpose of this test is to evaluate the Water Development Corporation's drilling system, modify components as necessary and determine compatible drilling applications for the sonic drilling method for use at facilities in the DOE complex. The sonic demonstration is being conducted as the first field test under the Cooperative Research and Development Agreement (CRADA) which involves the US Department of Energy, Pacific Northwest Laboratory, Westinghouse Hanford Company and Water Development Corporation. The sonic drilling system will be used to drill a 45 degree vadose zone well, two vertical wells at the VOC-Arid ID site, and several test holes at the Drilling Technology Test Site north of the 200 Area fire station. Testing at other locations will depend on the performance of the drilling method. Performance of this technology will be compared to the baseline drilling method (cable-tool)

Automated pipe handling systems for new and retrofit applications in shallow drilling markets

Energy Technology Data Exchange (ETDEWEB)

McDougall, P.; Fikowski, L.M. [Blackbird Well Servicing Inc., Calgary, AB (Canada)

2003-07-01

This presentation discussed the importance of the human interface as the main element in the development of automated mechanical systems on drilling rigs. Improvements in drilling rig designs are meant to improve manpower efficiencies and performance. The goal for Blackbird Well Servicing is to design automated and integrated processes that can be controlled manually at any point during an operation. Although some drilling operations can be fully automated and fully integrated, certain steps in the process are intentionally left open ended for human intervention. It was concluded that the consistency of performance is the most significant feature of integrated systems and that all drilling contractors should strive for smooth, steady performance rather than brute labour. Speed and efficiency increases with consistent performance. Reliability results in better performance, thereby lowering operating costs and more work for drilling contractors.

Water Hammer Mitigation on Postulated Pipe Break of Feed Water System

International Nuclear Information System (INIS)

Seong, Ho Je; Woo, Kab Koo; Cho, Keon Taek

2008-01-01

The Feed Water (FW) system supplies feedwater from the deaerator storage tank to the Steam Generators(S/G) at the required pressure, temperature, flow rate, and water chemistry. The part of FW system, from the S/G to Main Steam Valve House just outside the containment building wall, is designed as safety grade because of its safety function. According to design code the safety related system shall be designed to protect against dynamic effects that may results from a pipe break on high energy lines such as FW system. And the FW system should be designed to minimize blowdown volume of S/G secondary side during the postulated pipe break. Also the FW system should be designed to prevent the initiation or to minimize the effects of water hammer transients which may be induced by the pipe break. This paper shows the results of the hydrodynamic loads induced by the pipe break and the optimized design parameters to mitigate water hammer loads of FW system for Shin-Kori Nuclear Power Plant Unit 3 and 4 (SKN 3 and 4)

Vertebrobasilar dolichoectasia induced hydrocephalus: the water-hammer effect

Directory of Open Access Journals (Sweden)

Vaso Zisimopoulou

2015-05-01

Full Text Available Vertebrobasilar dolichoectasia is a clinical entity associated rarely with obstructive hydrocephalus. We present a 48-year old male with a profound dilatation of the ventricular system due to a dolichoectatic basilar artery, as appeared in imaging studies. The patient suffered from longstanding hydrocephalus and presenile dementia. The underlying mechanism for obstructive hydrocephalus due to vertebrobasilar dolichoectasia is considered to be both a water-hammer effect and a direct compression of adjacent structures. We suggest prompt surgical intervention upon diagnosis as a first choice treatment in order to avoid further complications.

Office microlaparoscopic ovarian drilling (OMLOD) versus conventional laparoscopic ovarian drilling (LOD) for women with polycystic ovary syndrome.

Science.gov (United States)

Salah, Imaduldin M

2013-02-01

This was a prospective controlled study to compare the beneficial effects of office microlaparoscopic ovarian drilling (OMLOD) under augmented local anesthesia, as a new modality treatment option, compared to those following ovarian drilling with the conventional traditional 10-mm laparoscope (laparoscopic ovarian drilling, LOD) under general anesthesia. The study included 60 anovulatory women with polycystic ovary syndrome (PCOS) who underwent OMLOD (study group) and 60 anovulatory PCOS women, in whom conventional LOD using 10-mm laparoscope under general anesthesia was performed (comparison group). Transvaginal ultrasound scan and blood sampling to measure the serum concentrations of LH, FSH, testosterone and androstenedione were performed before and after the procedure. Intraoperative and postoperative pain scores in candidate women were evaluated during the office microlaparoscopic procedure, in addition to the number of candidates who needed extra analgesia. Women undergoing OMLOD showed good intraoperative and postoperative pain scores. The number of patients discharged within 2 h after the office procedure was significantly higher, without the need for postoperative analgesia in most patients. The LH:FSH ratio, mean serum concentrations of LH and testosterone and free androgen index decreased significantly after both OMLOD and LOD. The mean ovarian volume decreased significantly (P < 0.05) a year after both OMLOD and LOD. There were no significant differences in those results after both procedures. Intra- and postoperatively augmented local anesthesia allows outpatient bilateral ovarian drilling by microlaparoscopy without general anesthesia. The high pregnancy rate, the simplicity of the method and the faster discharge time offer a new option for patients with PCOS who are resistant to clomiphene citrate. Moreover, ovarian drilling could be performed simultaneously during the routine diagnostic microlaparoscopy and integrated into the fertility workup of

Assessment of water hammer effects on boiling water nuclear reactor core dynamics

Directory of Open Access Journals (Sweden)

Bousbia-Salah Anis

2007-01-01

Full Text Available Complex phenomena, as water hammer transients, occurring in nuclear power plants are still not very well investigated by the current best estimate computational tools. Within this frame work, a rapid positive reactivity addition into the core generated by a water hammer transient is considered. The numerical simulation of such phenomena was carried out using the coupled RELAP5/PARCS code. An over all data comparison shows good agreement between the calculated and measured core pressure wave trends. However, the predicted power response during the excursion phase did not correctly match the experimental tendency. Because of this, sensitivity studies have been carried out in order to identify the most influential parameters that govern the dynamics of the power excursion. After investigating the pressure wave amplitude and the void feed back responses, it was found that the disagreement between the calculated and measured data occurs mainly due to the RELAP5 low void condensation rate which seems to be questionable during rapid transients. .

A parametric study of condensation-induced water hammer in nuclear power plants

International Nuclear Information System (INIS)

Shon, Young Uk; Chun, Moon Hyun

1990-01-01

Condensation-induced water hammer (CIWH), which may occur in systems involving steam and water simultaneously, has a series of processes such as formation of water slug, trapping a steam cavity, depressurization due to steam condensation, accelerating slug caused pressure difference over it and final slug impact. These processes are dependent on water flow rate in a pipe, water temperature, water subcooling, steam pressure, size of slug and cavity, and heat transfer coefficient at interface between steam and water. In the present work, the prediction of conditions to initiate water hammer has been made with full scale by applying the open channel flow theory. These conditions are expressed in terms of water flow rate according to changes of steam pressure, water subcooling, and pipe diameter. Under these conditions that induce CIWH, the effect of parameters which influence on slug impact pressure and cavity collapse rate have been studied with full scale. Also, the impact loads that may be applied to piping design were evaluated under various system conditions

Activity plan: Directional drilling and environmental measurements while drilling

International Nuclear Information System (INIS)

Myers, D.A.

1998-01-01

This activity plan describes the testing of directional drilling combined with environmental measurements while drilling at two Hanford Site locations. A cold test is to be conducted at the 105A Mock Tank Leak Facility in the 200 East Area. A hot test is proposed to be run at the 216-B-8 tile field north of the 241-B Tank Farm in 200 East Area. Criteria to judge the success, partial success or failure of various aspects of the test are included. The TWRS program is assessing the potential for use of directional drilling because of an identified need to interrogate the vadose zone beneath the single-shell tanks. Because every precaution must be taken to assure that investigation activities do not violate the integrity of the tanks, control of the drill bit and ability to follow a predetermined drill path are of utmost importance and are being tested

Case drilling - an innovative approach to reducing drilling costs

Energy Technology Data Exchange (ETDEWEB)

Madell, G.; Tessari, R. M. [Tesco Corp., Calgary, AB (Canada); Warren, T. [Tesco Drilling Technology, Calgary, AB (Canada)

1999-11-01

Casing drilling is introduced as a new drilling technique that uses standard oil field casing to simultaneously drill and case the well. The technology includes both rig and downhole equipment, customized to function effectively as an integrated drilling system. This paper describes the testing program designed to identify and overcome technical challenges. Although not fully optimized, it appears that the system is functional. Test results indicate the need for improvements in the pump down cement float equipment and the tools and procedures for drilling up the cement plugs. The pump down latch and retrieval system also needs to be further developed and tested for high angle directional applications. Cost savings in the range of 10 to 15 per cent are expected for trouble-free wells. By eliminating the cost of unscheduled events encountered in troublesome wells, cost savings may reach as high as 30 per cent. 3 refs., 7 figs.

Activity plan: Directional drilling and environmental measurements while drilling

Energy Technology Data Exchange (ETDEWEB)

Myers, D.A.

1998-07-16

This activity plan describes the testing of directional drilling combined with environmental measurements while drilling at two Hanford Site locations. A cold test is to be conducted at the 105A Mock Tank Leak Facility in the 200 East Area. A hot test is proposed to be run at the 216-B-8 tile field north of the 241-B Tank Farm in 200 East Area. Criteria to judge the success, partial success or failure of various aspects of the test are included. The TWRS program is assessing the potential for use of directional drilling because of an identified need to interrogate the vadose zone beneath the single-shell tanks. Because every precaution must be taken to assure that investigation activities do not violate the integrity of the tanks, control of the drill bit and ability to follow a predetermined drill path are of utmost importance and are being tested.

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

International Nuclear Information System (INIS)

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

1999-01-01

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 minus8 m (minus27 ft.), following a predetermined drill path, tracking the drill path to within a radius of approximately1.5 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 ∼ -21 m (-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

Prime costs and economic efficiency of deep drilling in Chechen-Ingush ASSR

Energy Technology Data Exchange (ETDEWEB)

Umanskii, L.M.

1982-04-01

The possibilities of reducing the prime costs of deep well drilling and improving the efficiency of drilling are considered. The dynamics of performance over the last two five-year plan (FYP) periods is analyzed and it is shown that the performance in the 10th FYP did not improve as compared to the 9th FYP. This is due to geological conditions and shortcomings in the technology and organization of drilling. It is shown that the speed and depth of drilling are decisive factors influencing costs.

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

Directory of Open Access Journals (Sweden)

Ladeesh V G

2016-01-01

Full Text Available 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 action. In this study, the effect of process parameters like voltage, duty cycle, cycle time and electrolyte concentration on material removed (MR was investigated systematically using response surface methodology. Analysis of variance was performed to identify the significant factors and their percentage contribution. The most significant factor was found to be duty cycle followed by voltage, cycle time and concentration. A quadratic mathematical model was developed to predict MR. Tool wear was found for different frequencies and voltages. Higher tool wear was observed for high frequency above 5kHz pulsed DC supply at high voltage of 110V. Tool wear at the end face of the tool was found to be a significant problem affecting the tool life.

The Swedish Deep Drilling Program - an emerging scientific drilling program and new infrastructure.

Science.gov (United States)

Lorenz, Henning; Juhlin, Christopher

2010-05-01

Scientific drilling projects imply numerous aspects that are difficult to handle for individual research groups. Therefore, about three years ago a joint effort was launched in the Swedish geoscientific community to establish a national program for scientific drilling, the Swedish Deep Drilling Program (SDDP). Soon afterwards, several working groups established drilling proposals with Nordic and, also, international participation. With this serious interest in scientific drilling SDDP was able to successfully promote the Swedish membership in ICDP which commenced in 2008. Two SDDP projects achieved workshop grants from the International Continental Scientific Drilling Program (ICDP) in 2009. In the same year the Swedish Research Council decided to support an application for a truck-mounted drill rig - a big success for the SDDP working group. Scientific Drilling infrastructure: SDDP envisages a mobile platform that is capable of core drilling to at least 2500 m depth. The procurement will be made during 2010 and first operations are planned for 2011. This drill rig is primarily intended for use in the SDDP drilling projects, but will be rented out to other scientific drilling projects or even commercial enterprises in the remaining time to cover maintenance and future upgrade costs. SDDP's drill rig will be unique in Europe and complementary to the deep drilling InnovaRig of the GFZ German Research Centre for Geosciences. Until now, drilling to 2000 - 3000 m implied the use of a full-sized drill rig like the InnovaRig or the mobilization of a core drill rig from another continent. This gap will now be filled by Sweden's upcoming scientific drilling infrastructure. Drilling projects and proposals: Presently, SDDP serves six projects: "Collisional Orogeny in the Scandinavian Caledonides" (COSC; ICDP workshop spring 2010), the "Postglacial Fault Drilling Project" (PFDP; ICDP workshop autumn 2010), a "Deep Rock Laboratory" (DRL), "Palaeoproterozoic Mineralized Volcanic

Drilling cost analysis

International Nuclear Information System (INIS)

Anand, A.B.

1992-01-01

Drilling assumes greater importance in present day uranium exploration which emphasizes to explore more areas on the basis of conceptual model than merely on surface anomalies. But drilling is as costly as it is important and consumes a major share (50% to 60%) of the exploration budget. As such the cost of drilling has great bearing on the exploration strategy as well as on the overall cost of the project. Therefore, understanding the cost analysis is very much important when planning or intensifying an exploration programme. This not only helps in controlling the current operations but also in planning the budgetary provisions for future operations. Also, if the work is entrusted to a private party, knowledge of in-house cost analysis helps in fixing the rates of drilling in different formations and areas to be drilled. Under this topic, various factors that contribute to the cost of drilling per meter as well as ways to minimize the drilling cost for better economic evaluation of mineral deposits are discussed. (author)

Structural dynamics and fracture mechanics calculations of the behaviour of a DN 425 test piping system subjected to transient loading by water hammer

International Nuclear Information System (INIS)

Kussmaul, K.; Kobes, E.; Diem, H.; Schrammel, D.; Brosi, S.

1994-01-01

Within the scope of the German HDR safety programme, several tests were carried out to investigate transient pipe loading initiated by a simulated double-ended guillotine break event, and subsequent closure of a feedwater check valve (water hammer, blow-down). Numerical analyses by means of finite element programmes were performed in parallel to the experiments. Using water hammer tests of a DN 425 piping system with predamaged components, the procedure of such analyses will be demonstrated. The results are presented, beginning with structural dynamic calculations of the undamaged piping; followed by coupling of structural dynamics and fracture mechanics computations with simple flaw elements (line spring); and finishing with costly three-dimensional fracture mechanics analyses. A good description of the real piping behaviour can be made by the numerical methods, even in the case of high plastification processes. ((orig.))

Laser Drilling - Drilling with the Power of Light

Energy Technology Data Exchange (ETDEWEB)

Iraj A. Salehi; Brian C. Gahan; Samih Batarseh

2007-02-28

Gas Technology Institute (GTI) has been the leading investigator in the field of high power laser applications research for well construction and completion applications. Since 1997, GTI (then as Gas Research Institute- GRI) has investigated several military and industrial laser systems and their ability to cut and drill into reservoir type rocks. In this report, GTI continues its investigation with a 5.34 kW ytterbium-doped multi-clad high power fiber laser (HPFL). When compared to its competitors; the HPFL represents a technology that is more cost effective to operate, capable of remote operations, and requires considerably less maintenance and repair. Work performed under this contract included design and implementation of laboratory experiments to investigate the effects of high power laser energy on a variety of rock types. All previous laser/rock interaction tests were performed on samples in the lab at atmospheric pressure. To determine the effect of downhole pressure conditions, a sophisticated tri-axial cell was designed and tested. For the first time, Berea sandstone, limestone and clad core samples were lased under various combinations of confining, axial and pore pressures. Composite core samples consisted of steel cemented to rock in an effort to represent material penetrated in a cased hole. The results of this experiment will assist in the development of a downhole laser perforation or side tracking prototype tool. To determine how this promising laser would perform under high pressure in-situ conditions, GTI performed a number of experiments with results directly comparable to previous data. Experiments were designed to investigate the effect of laser input parameters on representative reservoir rock types of sandstone and limestone. The focus of the experiments was on laser/rock interaction under confining pressure as would be the case for all drilling and completion operations. As such, the results would be applicable to drilling, perforation, and

Water hammer experiences in the startup and early operation of the Shearon Harris plant

International Nuclear Information System (INIS)

Casada, D.A.

1987-01-01

During the course of preoperational testing and early operation of the Shearon Harris Nuclear Power Plant, several water hammer events have occurred. A description of the events and corrective/preventive measures taken are discussed

Robotic Planetary Drill Tests

Science.gov (United States)

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

2010-01-01

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.

Drilling trends in the nineties

International Nuclear Information System (INIS)

1993-01-01

At a conference on various aspects of well drilling in the 1990s, papers were presented on drilling waste management, well completion and workovers, drilling fluids, drilling rig equipment and design, drilling mechanics, drill stem testing and materials, cementing, business management, health and safety, environmental issues, and directional drilling technology. Separate abstracts have been prepared for 46 papers from this conference

Scientific Drilling with the Sea Floor Drill Rig MeBo

Directory of Open Access Journals (Sweden)

Gerold Wefer

2007-09-01

Full Text Available In March 2007 the sea floor drill rig MeBo (short for “Meeresboden-Bohrgerät”, ‘sea floor drill rig’ in German returned from a 17-day scientific cruise with the new German research vessel Maria S. Merian. Four sites between 350 m and 1700 m water depth were sampled at the continental slope off Morocco by push coring and rotary drilling. Up to 41.5-m-long sediment cores were recovered from Miocene, Pliocene, and Pleistocene marls. MeBo bridges the gapbetween conventional sampling methods from standard multipurpose research vessels (gravity corer, piston corer, dredges and drill ships. Most bigger research vessels will be able to support deployment of the MeBo. Since the drill system can be easily transported within 20-ft containers, worldwide operation from vessels of opportunity is possible. With the MeBo a new system is available for marine geosciences that allows the recovery of high quality samples from soft sediments and hard rock from the deep sea withoutrelying on the services of expensive drilling vessels.

Hole quality and burr reduction in drilling aluminium sheets

DEFF Research Database (Denmark)

Pilny, Lukas; De Chiffre, Leonardo; Piska, Miroslav

2011-01-01

Optimization of the metal drilling process requires creation of minimum amount of burrs and uniform appearance of the drilled holes. In this paper, an experimental investigation was performed on 2 mm sheets of wrought aluminium alloy Al99.7Mg0.5Cu-H24, using 1.6 and 2 mm diameter drills. Cutting...... data, clamping conditions, and drill geometry were varied in order to optimize the process and reach the desired quality. The results revealed possible reduction of burr occurrence on both the entry and exit side of the sheet, requiring no additional deburring. The demand on the uniform appearance...... of drilled holes was fulfilled as well as high productivity achieved. Such optimized process results in a noticeable production cost reduction....

Hole quality and burr reduction in drilling aluminium sheets

DEFF Research Database (Denmark)

Pilny, Lukas; De Chiffre, Leonardo; Piska, Miroslav

2012-01-01

Optimization of the metal drilling process requires creation of minimum amount of burrs and uniform appearance of the drilled holes. In this paper, an experimental investigation was performed on 2 mm sheets of wrought aluminium alloy Al99.7Mg0.5Cu-H24, using 1.6 and 2 mm diameter drills. Cutting...... data, clamping conditions, and drill geometry were varied in order to optimize the process and reach the desired quality. The results revealed possible reduction of burr occurrence on both the entry and exit side of the sheet, requiring no additional deburring. The demand on the uniform appearance...... of drilled holes was fulfilled as well as high productivity achieved. Such optimized process results in a noticeable production cost reduction....

Drilling contract issues

International Nuclear Information System (INIS)

Davison, G.B.; Worden, D.R.; Borbridge, G.K.D.

1997-01-01

Some selected issues which are facing both operators and contractors in drilling for oil and gas, such as the allocation of risk by contract and by statute and the implementation of new technologies, were discussed. There are three varieties of written drilling contracts used in Canada: (1) day work and meterage contracts, (2) master drilling agreements, and (3) contracts that are used in construction projects that do not specifically relate to drilling. Issues relevant to the contractual allocation of risk, to implementing new drilling technologies, to reconciling contract and statute liability, and the formation of strategic alliances for mutual benefit, and the factors contributing to the success of such alliances were explored. 12 refs

Advantages and limitations of remotely operated sea floor drill rigs

Science.gov (United States)

Freudenthal, T.; Smith, D. J.; Wefer, G.

2009-04-01

A variety of research targets in marine sciences including the investigation of gas hydrates, slope stability, alteration of oceanic crust, ore formation and palaeoclimate can be addressed by shallow drilling. However, drill ships are mostly used for deep drillings, both because the effort of building up a drill string from a drill ship to the deep sea floor is tremendous and control on drill bit pressure from a movable platform and a vibrating drill string is poor especially in the upper hundred meters. During the last decade a variety of remotely operated drill rigs have been developed, that are deployed on the sea bed and operated from standard research vessels. These developments include the BMS (Bentic Multicoring System, developed by Williamson and Associates, operated by the Japanese Mining Agency), the PROD (Portable Remotely Operated Drill, developed and operated by Benthic Geotech), the Rockdrill 2 (developed and operated by the British geological Survey) and the MeBo (German abbreviation for sea floor drill rig, developed and operated by Marum, University of Bremen). These drill rigs reach drilling depths between 15 and 100 m. For shallow drillings remotely operated drill rigs are a cost effective alternative to the services of drill ships and have the major advantage that the drilling operations are performed from a stable platform independent of any ship movements due to waves, wind or currents. Sea floor drill rigs can be deployed both in shallow waters and the deep sea. A careful site survey is required before deploying the sea floor drill rig. Slope gradient, small scale topography and soil strength are important factors when planning the deployment. The choice of drill bits and core catcher depend on the expected geology. The required drill tools are stored on one or two magazines on the drill rig. The MeBo is the only remotely operated drill rig world wide that can use wire line coring technique. This method is much faster than conventional

South African drilling

International Nuclear Information System (INIS)

Anon.

1984-01-01

According to the president of the South African Drilling Association, the drilling industry is meeting head-on the challenges created by the worldwide recession. The paper is a synopsis of several of the papers presented at the SADA symposium and a look at several mining-related drilling projects in South Africa. These papers include grouting techniques, the use of impregnated bits in hard rock drilling, tunnel boring for mines, surveying improvement methods and the use of explosives to increase groundwater yield

A new drilling method—Earthworm-like vibration drilling

Science.gov (United States)

Wang, Peng; Wang, Ruihe

2018-01-01

The load transfer difficulty caused by borehole wall friction severely limits the penetration rate and extended-reach limit of complex structural wells. A new friction reduction technology termed “earthworm-like drilling” is proposed in this paper to improve the load transfer of complex structural wells. A mathematical model based on a “soft-string” model is developed and solved. The results show that earthworm-like drilling is more effective than single-point vibration drilling. The amplitude and frequency of the pulse pressure and the installation position of the shakers have a substantial impact on friction reduction and load transfer. An optimization model based on the projection gradient method is developed and used to optimize the position of three shakers in a horizontal well. The results verify the feasibility and advantages of earthworm-like drilling, and establish a solid theoretical foundation for its application in oil field drilling. PMID:29641615

Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

International Nuclear Information System (INIS)

Elmsheuser, Johannes; Legger, Federica; Llamas, Ramón Medrano; Sciabà, Andrea; García, Mario Úbeda; Ster, Daniel van der; Sciacca, Gianfranco

2012-01-01

Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion policies. A study of the historical test results for ATLAS, CMS and LHCb will be presented, including comparisons between the experiments’ grid availabilities and a search for site-based or temporal failure correlations. Finally, we will look to future plans that will allow users to gain new insights into the test results; these include developments to allow increased testing concurrency, increased scale in the number of metrics recorded per test job (up to hundreds), and increased scale in the historical job information (up to many millions of jobs per VO).

Experience in Grid Site Testing for ATLAS, CMS and LHCb with HammerCloud

Science.gov (United States)

Elmsheuser, Johannes; Medrano Llamas, Ramón; Legger, Federica; Sciabà, Andrea; Sciacca, Gianfranco; Úbeda García, Mario; van der Ster, Daniel

2012-12-01

Frequent validation and stress testing of the network, storage and CPU resources of a grid site is essential to achieve high performance and reliability. HammerCloud was previously introduced with the goals of enabling VO- and site-administrators to run such tests in an automated or on-demand manner. The ATLAS, CMS and LHCb experiments have all developed VO plugins for the service and have successfully integrated it into their grid operations infrastructures. This work will present the experience in running HammerCloud at full scale for more than 3 years and present solutions to the scalability issues faced by the service. First, we will show the particular challenges faced when integrating with CMS and LHCb offline computing, including customized dashboards to show site validation reports for the VOs and a new API to tightly integrate with the LHCbDIRAC Resource Status System. Next, a study of the automatic site exclusion component used by ATLAS will be presented along with results for tuning the exclusion policies. A study of the historical test results for ATLAS, CMS and LHCb will be presented, including comparisons between the experiments’ grid availabilities and a search for site-based or temporal failure correlations. Finally, we will look to future plans that will allow users to gain new insights into the test results; these include developments to allow increased testing concurrency, increased scale in the number of metrics recorded per test job (up to hundreds), and increased scale in the historical job information (up to many millions of jobs per VO).

The Hans Tausen drill

DEFF Research Database (Denmark)

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