Reactor vessel stud closure system

International Nuclear Information System (INIS)

Spiegelman, S.R.; Salton, R.B.; Beer, R.W.; Malandra, L.J.; Cognevich, M.L.

1982-01-01

A quick-acting stud tensioner apparatus for enabling the loosening or tightening of a stud nut on a reactor vessel stud. The apparatus is adapted to engage the vessel stud by closing a gripper around an upper end of the vessel stud when the apparatus is seated on the stud. Upon lifting the apparatus, the gripper releases the vessel stud so that the apparatus can be removed

Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic technique

International Nuclear Information System (INIS)

Lee, Joon-Hyun; Choi, Sang-Woo; Oh, Won-Deok

2004-01-01

The stud bolt is one of crucial parts for safety of reactor vessels in nuclear power plants. Crack initiation and propagation were reported in stud bolts using closure of reactor vessel and head. Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure and radioactive leakage from nuclear reactor. In conventional ultrasonic testing for inspection of stud bolts, crack was detected by using shadow effect. It takes too much time to inspect stud bolt by using conventional ultrasonic technique. In addition, there were numerous spurious signals reflected from every oblique surfaces of thread. In this study, the signal processing technique for enhancing conventional ultrasonic technique and the advanced ultrasonic phased array technique were introduced for inspect stud bolts. The signal processing technique provides removing spurious signal reflected from every oblique surfaces of thread and enhances detectability of defects. The phased array technique provides fast inspection and can be applied for structure of complex shape. There are sector scanning and linear scanning methods in phased array technique, and these scanning methods were applied to inspect stud bolt and detectability was investigated. (author)

Reactor vessel stud tensioner

International Nuclear Information System (INIS)

Malandra, L.J.; Beer, R.W.; Salton, R.B.; Spiegelman, S.R.; Cognevich, M.L.

1982-01-01

A quick-acting stud tensioner, for facilitating the loosening or tightening of a stud nut on a reactor vessel stud, has gripper jaws which when the tensioner is lowered into engagement with the upper end of the stud are moved inwards to grip the upper end and which when the tensioner is lifted move outward to release the upper end. (author)

Ultrasonic Phased Array Techniques for Detection of Flaws of Stud Bolts in Nuclear Power Plants

International Nuclear Information System (INIS)

Lee, Joon Hyun; Choi, Sang Woo

2006-01-01

The reactor vessel body and closure head are fastened with the stud bolt that is one of crucial parts for safety of the reactor vessels in nuclear power plants. It is reported that the stud bolt is often experienced by fatigue cracks initiated at threads. Stud bolts are inspected by the ultrasonic technique during the overhaul periodically for the prevention of failure which leads to radioactive leakage from the nuclear reactor. The conventional ultrasonic inspection for stud bolts was mainly conducted by reflected echo method based on shadow effect. However, in this technique, there were numerous spurious signals reflected from every oblique surfaces of the thread. In this study, ultrasonic phased array technique was applied to investigate detectability of flaws in stud bolts and characteristics of ultrasonic images corresponding to different scanning methods, that is, sector and linear scan. For this purpose, simplified stud bolt specimens with artificial defects of various depths were prepared

Causes of Failure of High-Tensile Stud Bolts Used for Joining Metal Parts of Tower Crane

Science.gov (United States)

Tingaev, A. K.; Gubaydulin, R. G.; Shaburova, N. A.

2017-11-01

The causes of the failure of a high-tensile stud 2M48-6gx500 10.9 made from steel grade 30HGSA which led to a temporary inoperability of a tower crane were investigated. The bolts were used to assemble the tower sections and collapsed after 45 days from the moment the crane was commissioned. The cracks in the fracture are identified as fatigue with the characteristic sites of nucleation, sustainable development and static dolomite. To determine the possible causes of stud bolts destruction, metallographic, durometric and mechanical tests were carried out from which it follows that the stud bolt material in its original state corresponded to the delivery conditions. The destruction of the stud bolt appears to have resulted from a combination of several unfavorable factors: uncertainty about the actual tension of the stud bolt due to the lack of information about the magnitude of the twist factor; partial displacement of the centers of the brackets holes and rotation of the stud bolt axis during the sections’ assembly; no tight contact on the support surfaces of the section brackets. All this led to a discrepancy between the actual design of the stud bolt, the appearance of additional forces and the destruction of the stud bolt.

Improvement in or relating to bolts or studs

International Nuclear Information System (INIS)

Seward, W.H.

1977-01-01

Reference is made to anti-seize bolts or studs for use in extreme conditions, such as in nuclear power plants. A number of methods have been proposed for avoiding seizure, but have met with limited success. One approach to this problem is to coat the surfaces of the steel bolt in such a way that the contacting surfaces of the bolt and its associated nut are sufficiently dissimilar for molecular seizure to be avoided. It has been discovered that greatly improved resistance to seizing can be obtained by hard plating the entire thread of an alloy steel bolt with Cr. After Cr plating the bolt is de-embrittled by suitable heat treatment. (U.K.)

Ultrasonic Inspection of Cracks in Stud Bolts of Reactor Vessels in Nuclear Power Plants by Signal Processing of Differential Operation

International Nuclear Information System (INIS)

Choi, Sang Woo; Lee, Joon Hyun; Oh, Won Deok

2005-01-01

The stud bolt is one of crucial parts for safe operation of reactor vessels in nuclear power plants, Crack initiation and propagation were reported in stud bolts that arc used for closure of reactor vessel and head, Stud bolts are inspected by ultrasonic technique during overhaul periodically for the prevention of stud bolt failure which could induce radioactive leakage from nuclear reactor, In conventional ultrasonic testing for inspection of stud bolts, cracks are detected by using shadow effect It takes too much time to inspect stud bolts by using conventional ultrasonic technique. In addition, there were numerous spurious signals reflected from every oblique surfaces of thread, In this study, the signal processing technique for enhancing conventional ultrasonic technique was introduced for inspecting stud bolts. The signal processing technique provides removing spurious signal reflected from every oblique surfaces of thread and enhances detectability of defects. Detectability for small crack was enhanced by using this signal processing in ultrasonic inspection of stud bolts in Nuclear Power Plants

Can electronic stability control replace studded tyres?

DEFF Research Database (Denmark)

Elvik, Rune

2015-01-01

Highlights • Electronic stability control can substitute studded tyres. • This makes it easier to discourage the use of studded tyres. • A certain level of use of studded tyres makes roads less slippery.......Highlights • Electronic stability control can substitute studded tyres. • This makes it easier to discourage the use of studded tyres. • A certain level of use of studded tyres makes roads less slippery....

Detection of stress corrosion cracks in reactor pressure vessel and primary coolant system anchor studs

International Nuclear Information System (INIS)

Light, G.M.; Joshi, N.R.

1987-01-01

Under Electric Power Research Institute (EPRI) contract No. 2179-2, southwest Research Institute is continuing work on the use of the cylindrically guided wave technique (CGWT) for inspecting stud bolts. Also being evaluated is the application of the CGWT to the inspection of reactor coolant pump shafts. Data have been collected for stud bolts ranging from 16 to 112 inches (40.6 to 285 cm) in length, and from 1 to 4.5 inches (2.54 to 11.4 cm) in diameter. For each bolt size, tests were conducted to determine the smallest detectable notch, the effect of thread noise, and the amount of detectable simulated corrosion. The ratio of reflected longitudinal signals to mode-converted signals was analyzed with respect to bolt diameter, bolt length, and frequency parameters. The results of these test showed the following: (1) The minimum detectable notch in the threaded region was approximately 0.05 inch (1.3 mm) for all stud bolts evaluated. (2) Thread noise could easily be detected, but the level of noise was below the minimum detectable notch signal. (3) For carbon steel, optimum transducer frequency was 5 MHz, using a transducer whose face had an impedance that matched the steel surface. (4) Simulated corrosion of 15% reduced diameter could be detected

Research and tests of steel-concrete-steel sandwich composite shear wall in reactor containment of HTR-PM

International Nuclear Information System (INIS)

Sun Yunlun; Huang Wen; Zhang Ran; Zhang Pei; Tian Chunyu

2014-01-01

By quasi-static test of 8 specimens of steel-concrete-steel sandwich composite shear wall, the bearing capacity, hysteretic behavior, failure mode of the specimens was studied. So was the effect of the shear-span ratios, steel ratios and spacing of studs on the properties of the specimens. The failure patterns of all specimens with different shear-span ratios between 1.0 and 1.5 were compression-bending failure. The hysteretic curves of all specimens were relatively plump, which validated the well deformability and energy dissipation capacity of the specimens. When shear-span ratio less than 1.5, the shear property of the steel plate was well played, and so was the deformability of the specimens. The bigger the steel ratio was, the better the lateral resistance capacity and the deformability was. Among the spacing of studs in the test, the spacing of studs had no significant effect on the bearing capacity, deformability and ductility of the specimens. Based on the principle of superposition an advised formula for the compression-bending capacity of the shear wall was proposed, which fitted well with the test result and had a proper safety margin. (author)

Behavior of Equipment Support Beam Joint Directly Connected to A Steel-plate Concrete(SC) Wall

International Nuclear Information System (INIS)

Kim, K. S.; Kwon, K. J.

2008-01-01

To decrease the time for building nuclear power plants, a modular construction method, 'Steel-plate Concrete(SC)', has been investigated for over a decade. To construct a SC wall, a pair of steel plates are placed in parallel similar to a form-work in conventional reinforced concrete (RC) structures, and concrete is filled between the steel plates. Instead of removing the steel plates after the concrete has cured, the steel plates serve as components of the structural member. The exposed steel plate of SC structures serves as the base plate for the equipment support, and the headed studs welded to the steel plates are used as anchor bolts. Then, a support beam can be directly welded to the surface of the steel plate in any preferred position. In this study, we discuss the behavior and evaluation method of the equipment support joint directly connected to exposed steel plate of SC wall

Experimental Study for Effects of the Stud shape of the Core Catcher System

Energy Technology Data Exchange (ETDEWEB)

Song, Kyusang; Son, Hong Hyun; Jeong, Uiju; Seo, Gwang Hyeok; Shin, Doyoung; Jeun, Gyoodong; Kim, Sung Joong [Hanyang University, Seoul (Korea, Republic of)

2015-05-15

In preparation of potential severe accidents, a nuclear power plant is equipped with diverse systems of engineering safety features or mitigation system dedicated to the severe accidents conditions. As a common strategy, a number of nuclear power plants adopt the in-vessel retention (IVR) and/or external reactor vessel cooling (ERVC) strategies. With the ERVC strategy, an additional system (core catcher system) to catch molten core penetrating the reactor pressure vessel (RPV) was proposed for advanced light water reactor. The core catcher system is for Ex-vessel in the European Advanced Power Reactor 1400 (EU-APR1400) to acquire a European license certificate. It is to confine molten materials in the reactor cavity while keeping coolable geometry in case that the RPV failure occurs. The system consists of a carbon steel body, sacrificial material, protection material and engineered cooling channel. As shown in Fig 1, the engineered cooling channel of the ex-vessel core catcher was adopted to remove sensible heat and decay heat of the molten corium using cooling water flooded from the In-Containment Refueling Water Storage Tank (IRWST) by gravity. A large number of studs are placed in the cooling channel to support the core catcher body. While installation of the studs is unavoidable, the studs tend to interfere in the smooth streamline of the core catcher channel. The distorted streamline could affect the temperature distribution and overall coolability of the system. Thus, it is of importance to investigate the effects of studs on the coolability of the core catcher system. In the current research, to evaluate the effect of a stud on the streamline and natural convective boiling performance, numerical and experimental approaches were taken. As a part of numerical approach, CFD simulation using ANSYS/FLUENT was carried out. The objective was to predict disturbance of the streamline and temperature distribution due to the interference of the studs. Through the CFD

Stud bolt handling equipment for reactor vessel

International Nuclear Information System (INIS)

Bunyan, T.W.

1989-01-01

Reactor vessel stud bolt handling equipment includes means for transferring a stud bolt to a carrier from a parking station, or vice versa. Preferably a number of stud bolts are handled simultaneously. The transfer means may include cross arms rotatable about extendable columns, and the equipment is mounted on a mobile base for movement into and out of position. Each carrier comprises a tubular socket and an expandable sleeve to grip a stud bolt. (author)

Extended suicide using an atypical stud gun.

Science.gov (United States)

Hagemeier, L; Schyma, C; Madea, B

2009-08-10

Suicides with stud guns are uncommon, but are well documented in the literature. On rare occasions, stud guns are also used as a homicide weapon. This case report describes an extended suicide in which a husband killed his wife and their two dogs, which lived on the property. The husband then committed suicide with a shot from the stud gun into his skull. He was a 70-year-old pensioner, a retired butcher, who was found by his son. He was lying in a supine position on a carpet in the living room, with the stud gun stuck in his skull. During autopsy, high concentrations of an antihistamine were found in the blood of each corpse; this drug is used as a soporific. In contrast to the literature, which mainly describes powder deposits due to the use of conventional stud guns, in this case a stud gun was used in which the expanding gases and powder escaped together with the central bolt at the front of the device; powder drains were not involved. Detailed findings of the autopsy are given with reference to this type of stud gun.

Thermal-Hydraulic Effects of Stud Shape and Size on the Safety Margin of Core Catcher System

Energy Technology Data Exchange (ETDEWEB)

Song, Kyusang; Son, Hong Hyun; Jeong, Uiju; Kim, Sung Joong [Hanyang University, Seoul (Korea, Republic of)

2015-10-15

With the ERVC strategy, an additional system (core catcher system) to catch molten core penetrating the reactor pressure vessel (RPV) was proposed for advanced light water reactor. The newly engineered corium cooling system, that is, an ex-vessel core catcher system has been designed and adapted in some nuclear power plants such as VVER-1000, EPR, ESBWR, EU-APR1400 to mention a few. For example, Russia adopted a crucible-type core catcher for VVER-1000. On the other hand, a way to catch melt spreading is adopted by several countries, such as EPR in France, ESBWR in USA, ABWR in japan, and EU-APR1400 in Korea In Korea, the core catcher system has been designed and implemented for the European Advanced Power Reactor 1400 (EU-APR1400) to acquire a European license certificate. It is to confine molten materials in the reactor cavity while maintaining a coolable geometry in case that RPV failure occurs. The core catcher system consists of a carbon steel body, sacrificial material, protection material and engineered cooling channel. While installation of the studs is unavoidable, the studs tend to interfere in the smooth streamline of the core catcher channel. The distorted streamline could affect the overall thermal-hydraulic performance including two-phase heat transfer coefficient and critical heat flux (CHF) of the system. Thus, it is of importance to investigate the thermal-hydraulic effects of studs on the coolability, especially the CHF of the core catcher system. With aforementioned importance, pool boiling experiments were carried out with stud shape of, rectangular, cylinder, and elliptic and for stud sizes of 10, 15, 20, and 25 mm under the condition of atmospheric saturated water. A particular attention was focused on observing local vapor behavior around the studs and finding any hot spots, where the vapors are accumulated. The occurrence of the CHF is anticipated at the back side of the studs. The visual observation and CHF measurements indicate that the

Thermal-Hydraulic Effects of Stud Shape and Size on the Safety Margin of Core Catcher System

International Nuclear Information System (INIS)

Song, Kyusang; Son, Hong Hyun; Jeong, Uiju; Kim, Sung Joong

2015-01-01

With the ERVC strategy, an additional system (core catcher system) to catch molten core penetrating the reactor pressure vessel (RPV) was proposed for advanced light water reactor. The newly engineered corium cooling system, that is, an ex-vessel core catcher system has been designed and adapted in some nuclear power plants such as VVER-1000, EPR, ESBWR, EU-APR1400 to mention a few. For example, Russia adopted a crucible-type core catcher for VVER-1000. On the other hand, a way to catch melt spreading is adopted by several countries, such as EPR in France, ESBWR in USA, ABWR in japan, and EU-APR1400 in Korea In Korea, the core catcher system has been designed and implemented for the European Advanced Power Reactor 1400 (EU-APR1400) to acquire a European license certificate. It is to confine molten materials in the reactor cavity while maintaining a coolable geometry in case that RPV failure occurs. The core catcher system consists of a carbon steel body, sacrificial material, protection material and engineered cooling channel. While installation of the studs is unavoidable, the studs tend to interfere in the smooth streamline of the core catcher channel. The distorted streamline could affect the overall thermal-hydraulic performance including two-phase heat transfer coefficient and critical heat flux (CHF) of the system. Thus, it is of importance to investigate the thermal-hydraulic effects of studs on the coolability, especially the CHF of the core catcher system. With aforementioned importance, pool boiling experiments were carried out with stud shape of, rectangular, cylinder, and elliptic and for stud sizes of 10, 15, 20, and 25 mm under the condition of atmospheric saturated water. A particular attention was focused on observing local vapor behavior around the studs and finding any hot spots, where the vapors are accumulated. The occurrence of the CHF is anticipated at the back side of the studs. The visual observation and CHF measurements indicate that the

AISI/DOE Technology Roadmap Program: Development of Cost-effective, Energy-efficient Steel Framing

Energy Technology Data Exchange (ETDEWEB)

Nader R. Elhajj

2003-01-06

Steel members in wall construction form a thermal bridge that interrupts the insulation layer of a wall. This causes higher rate of heat transfer by conduction through the wall framing than through other parts of the wall. One method to reduce the thermal bridging effect is to provide a break, such as insulating sheathing. A thermally efficient slit-web and stud was developed in this program to mitigate the conductivity of steel. The thermal performance of the slit-web stud was evaluated at Oak Ridge National Laboratory using hotbox testing. The thermal test results showed that the prototype slit-web stud performed 17% better than the solid-web stud, using R-13 fiber glass batts with exterior OSB sheathing and interior drywall. The structural behavior of this slit-web stud was evaluated in axial, bending, shear, shearwall, and stub-column tests. Test results indicated that the slitweb stud performed similarly or better than the solid-web stud in most structural performance characteristics investigated. Thus, the prototype slit-web stud has been shown to be thermally efficient, economiexecy viable, structurally sound, easily manufactured and usable in a range of residential installations.

Reduction of Biomechanical and Welding Fume Exposures in Stud Welding.

Science.gov (United States)

Fethke, Nathan B; Peters, Thomas M; Leonard, Stephanie; Metwali, Mahmoud; Mudunkotuwa, Imali A

2016-04-01

The welding of shear stud connectors to structural steel in construction requires a prolonged stooped posture that exposes ironworkers to biomechanical and welding fume hazards. In this study, biomechanical and welding fume exposures during stud welding using conventional methods were compared to exposures associated with use of a prototype system that allowed participants to weld from an upright position. The effect of base material (i.e. bare structural beam versus galvanized decking) on welding fume concentration (particle number and mass), particle size distribution, and particle composition was also explored. Thirty participants completed a series of stud welding simulations in a local apprenticeship training facility. Use of the upright system was associated with substantial reductions in trunk inclination and the activity levels of several muscle groups. Inhalable mass concentrations of welding fume (averaged over ~18 min) when using conventional methods were high (18.2 mg m(-3) for bare beam; 65.7 mg m(-3) for through deck), with estimated mass concentrations of iron (7.8 mg m(-3) for bare beam; 15.8 mg m(-3) for through deck), zinc (0.2 mg m(-3) for bare beam; 15.8 mg m(-3) for through deck), and manganese (0.9 mg m(-3) for bare beam; 1.5 mg m(-3) for through deck) often exceeding the American Conference of Governmental Industrial Hygienists Threshold Limit Values (TLVs). Number and mass concentrations were substantially reduced when using the upright system, although the total inhalable mass concentration remained above the TLV when welding through decking. The average diameters of the welding fume particles for both bare beam (31±17 nm) through deck conditions (34±34 nm) and the chemical composition of the particles indicated the presence of metallic nanoparticles. Stud welding exposes ironworkers to potentially high levels of biomechanical loading (primarily to the low back) and welding fume. The upright system used in this study improved exposure

Straight studs from southern pine veneer cores and cordwood

Science.gov (United States)

Peter Koch

1968-01-01

An economically feasible system has been developed for converting southern pine veneer cores into straight 8-foot studs (2). Prototype studs - two per core - were 100 percent SPIB stud grade and better.

Monitoring of Double-Stud Wall Moisture Conditions in the Northeast

Energy Technology Data Exchange (ETDEWEB)

Ueno, K. [Building Science Corporation, Westford, MA (United States)

2015-03-01

Double-stud walls insulated with cellulose or low-density spray foam can have R-values of 40 or higher. However, double-stud walls have a higher risk of interior-sourced condensation moisture damage when compared with high-R approaches using exterior insulating sheathing. Moisture conditions in double-stud walls were monitored in Zone 5A (Massachusetts); three double-stud assemblies were compared.

Monitoring of Double Stud Wall Moisture Conditions in the Northeast

Energy Technology Data Exchange (ETDEWEB)

Ueno, K. [Building Science Corporation, Westford, MA (United States)

2015-03-01

Double-stud walls insulated with cellulose or low-density spray foam can have R-values of 40 or higher. However, double stud walls have a higher risk of interior-sourced condensation moisture damage, when compared with high-R approaches using exterior insulating sheathing.; Moisture conditions in double stud walls were monitored in Zone 5A (Massachusetts); three double stud assemblies were compared.

Process and apparatus for optimizing screwing position for closure stud

International Nuclear Information System (INIS)

Bourdonne, J.C.; Briand, A.

1987-01-01

The stud is fixed to a screwing and unscrewing device. The vertical position and alignment of the stud with the axis of the threated hole is checking. The stud is descended into the hole and rotated in the unscrewing direction. After detection of the point of engagement, the stud is rotated in the screwing direction. When a gamming is detected the descent is stopped and the screwing device is positioned in a new position. When the screwing couple returns below the disconnection couple, the stud is rotated with a reduced speed and then with a normal speed until the end [fr

Effect of shear connectors on local buckling and composite action in steel concrete composite walls

International Nuclear Information System (INIS)

Zhang, Kai; Varma, Amit H.; Malushte, Sanjeev R.; Gallocher, Stewart

2014-01-01

Steel concrete composite (SC) walls are being used for the third generation nuclear power plants, and also being considered for small modular reactors. SC walls consist of thick concrete walls with exterior steel faceplates serving as reinforcement. These steel faceplates are anchored to the concrete infill using shear connectors, for example, headed steel studs. The steel faceplate thickness (t p ) and yield stress (F y ), and the shear connector spacing (s), stiffness (k s ), and strength (Q n ) determine: (a) the level of composite action between the steel plates and the concrete infill, (b) the development length of steel faceplates, and (c) the local buckling of the steel faceplates. Thus, the shear connectors have a significant influence on the behavior of composite SC walls, and should be designed accordingly. This paper presents the effects of shear connector design on the level of composite action and development length of steel faceplates in SC walls. The maximum steel plate slenderness, i.e., ratio of shear connector spacing-to-plate thickness (s/t p ) ratio to prevent local buckling before yielding is also developed based on the existing experimental database and additional numerical analysis

Effect of shear connectors on local buckling and composite action in steel concrete composite walls

Energy Technology Data Exchange (ETDEWEB)

Zhang, Kai, E-mail: kai-zh@purdue.edu [School of Civil Engineering, Purdue University, West Lafayette, IN (United States); Varma, Amit H., E-mail: ahvarma@purdue.edu [School of Civil Engineering, Purdue University, West Lafayette, IN (United States); Malushte, Sanjeev R., E-mail: smalusht@bechtel.com [Bechtel Power Corporation, Frederick, MD (United States); Gallocher, Stewart, E-mail: stewart.gallocher@steelbricks.com [Modular Walling Systems Ltd., Glasgow (United Kingdom)

2014-04-01

Steel concrete composite (SC) walls are being used for the third generation nuclear power plants, and also being considered for small modular reactors. SC walls consist of thick concrete walls with exterior steel faceplates serving as reinforcement. These steel faceplates are anchored to the concrete infill using shear connectors, for example, headed steel studs. The steel faceplate thickness (t{sub p}) and yield stress (F{sub y}), and the shear connector spacing (s), stiffness (k{sub s}), and strength (Q{sub n}) determine: (a) the level of composite action between the steel plates and the concrete infill, (b) the development length of steel faceplates, and (c) the local buckling of the steel faceplates. Thus, the shear connectors have a significant influence on the behavior of composite SC walls, and should be designed accordingly. This paper presents the effects of shear connector design on the level of composite action and development length of steel faceplates in SC walls. The maximum steel plate slenderness, i.e., ratio of shear connector spacing-to-plate thickness (s/t{sub p}) ratio to prevent local buckling before yielding is also developed based on the existing experimental database and additional numerical analysis.

Outage performance improvement by state of the art reactor stud tensioning

International Nuclear Information System (INIS)

Oehler, Horst Werner; Vervliet, Herman

2006-01-01

Actual methods of reactor closing, i.e. cover to vessel sealing, is based on the creation of an equal load to the sealing circumference by tensioning all reactor studs with an equal force. This method ensures leak tightness through equal compression of the reactor seal in normal circumstances and is largely applied for all types of reactors throughout many generations and designs of nuclear power stations. The tension generated in each reactor stud is controlled indirectly by measuring the reactor stud elongation while under stress. Most studs are designed to measure this elongation easily by conventional or more advanced systems (from individual clock gauge to integrated digital transmission to a computer screen). It is this elongation value, prescribed by the reactor vessel/cover manufacturer which must be respected and demonstrated during all reactor closing operations, weather they take place for initial hydro testing, refuelling operations or periodical hydraulic tests of the primary circuit. Closing (and re-opening) of reactor vessels has become a routine operation as it is required for fuel reloading of the reactor core. This operation is performed on all PWR and BWR type of reactors with a large variety of tooling. As most of the utilities have implemented maintenance optimisation programs, the refuelling outage is reduced to a sequence of activities that allow quick and efficient refuelling of the core. The performance and efficiency of instrumentation and tooling deployed during these essential activities are of the utmost importance to minimise the critical path of the refuelling outage. Today, in support of outage performance, many utilities have invested in new and refurbished tooling to allow quick and efficient opening and closing of the reactor vessel. The features and properties of the most performing multi stud tensioning machines currently in service in nuclear power stations world wide (Africa, Europe, Asia and USA) are presented in the paper

Ensayo no destructivo de soldaduras en pernos conectores mediante inspección acústica

OpenAIRE

Aznar, A.; Cervera, J.; Ortiz, J.; Hernando, J. I.

2012-01-01

Headed studs are nowadays the standard steel-concrete connectors because of their competitive advantages. Firstly, they provide a high degree of safety thanks to semiautomatic electric arc welding. These welds are not suitable for typical non-destructive tests. The analytical study comprises several models. The first vibration modes have been obtained. The experimental research has developed first the measurement of the natural frequencies of 28 headed-studs in the sonic range. Th...

Microstructures and Mechanical Properties of Friction Tapered Stud Overlap Welding for X65 Pipeline Steel Under Wet Conditions

Science.gov (United States)

Xu, Y. C.; Jing, H. Y.; Han, Y. D.; Xu, L. Y.

2017-08-01

This paper exhibits a novel in situ remediation technique named friction tapered stud overlap welding (FTSOW) to repair a through crack in structures and components in extremely harsh environments. Furthermore, this paper presents variations in process data, including rotational speed, stud displacement, welding force, and torque for a typical FTSOW weld. In the present study, the effects of welding parameters on the microstructures and mechanical properties of the welding joints were investigated. Inapposite welding parameters consisted of low rotational speeds and welding forces, and when utilized, they increased the occurrence of a lack of bonding and unfilled defects within the weld. The microstructures with a welding zone and heat-affected zone mainly consisted of upper bainite. The hardness value was highest in the welding zone and lowest in the base material. During the pull-out tests, all the welds failed in the stud. Moreover, the defect-free welds broke at the interface of the lap plate and substrate during the cruciform uniaxial tensile test. The best tensile test results at different depths and shear tests were 721.6 MPa and 581.9 MPa, respectively. The favorable Charpy impact-absorbed energy was 68.64 J at 0 °C. The Charpy impact tests revealed a brittle fracture characteristic with a large area of cleavage.

A Synthesis on the Evolution of the Studded Tire

National Research Council Canada - National Science Library

Angerinos, Michael

1998-01-01

Ever since studded tires were flrst introduced, the advantages, disadvantages, and effects of studded tires on vehicles, drivers and pavement systems has been the center of research and controversy...

Straight studs are produced from southern pine cordwood

Science.gov (United States)

Peter Koch

1967-01-01

A Process for converting southern pine veneer cores into 8-foot 2 by 4's of SPIB Stud grade and better has been developed at the Alexandria, Louisiana, Utilization Laboratory of the Southern Forest Experiment Station. The research leading to this development suggests that a similiar process would be practical for converting 8-foot southern pine cordwood into studs...

Friction Hydro-Pillar Processing of a High Carbon Steel: Joint Structure and Properties

Science.gov (United States)

Kanan, Luis Fernando; Vicharapu, Buchibabu; Bueno, Antonio Fernando Burkert; Clarke, Thomas; De, Amitava

2018-04-01

A coupled experimental and theoretical study is reported here on friction hydro-pillar processing of AISI 4140 steel, which is a novel solid-state joining technique to repair and fill crack holes in thick-walled components by an external stud. The stud is rotated and forced to fill a crack hole by plastic flow. During the process, frictional heating occurs along the interface of the stud and the wall of crack hole leading to thermal softening of the stud that eases its plastic deformation. The effect of the stud force, its rotational speed and the total processing time on the rate of heat generation and resulting transient temperature field is therefore examined to correlate the processing variables with the joint structure and properties in a systematic and quantitative manner, which is currently scarce in the published literature. The results show that a gentler stud force rate and greater processing time can promote proper filling of the crack hole and facilitate a defect-free joint between the stud and original component.

Roll forming of eco-friendly stud

Science.gov (United States)

Keum, Y. T.; Lee, S. Y.; Lee, T. H.; Sim, J. K.

2013-12-01

In order to manufacture an eco-friendly stud, the sheared pattern is designed by the Taguchi method and expanded by the side rolls. The seven geometrical shape of sheared pattern are considered in the structural and thermal analyses to select the best functional one in terms of the durability and fire resistance of dry wall. For optimizing the size of the sheared pattern chosen, the L9 orthogonal array and smaller-the-better characteristics of the Taguchi method are used. As the roll gap causes forming defects when the upper-and-lower roll type is adopted for expanding the sheared pattern, the side roll type is introduced. The stress and strain distributions obtained by the FEM simulation of roll-forming processes are utilized for the design of expanding process. The expanding process by side rolls shortens the length of expanding process and minimizes the cost of dies. Furthermore, the stud manufactured by expanding the sheared pattern of the web is an eco-friend because of the scrapless roll-forming process. In addition, compared to the conventionally roll-formed stud, the material cost is lessened about 13.6% and the weight is lightened about 15.5%.

A Preliminary Study of the Core Catcher System on Various Stud Shapes using FLUENT

Energy Technology Data Exchange (ETDEWEB)

Jeong, Uiju; Seo, Gwang Hyeok; Jeun, Gyoodong; Kim, Sung Joong [Hanyang University, Seoul (Korea, Republic of)

2014-10-15

As a kind of in-vessel retention (IVR) strategies, reactor cavity flooding is used for Westinghouse's AP1000 and South Korea's OPR1000. Moreover, the European Pressurized Reactor (EPR) has adopted an ex-vessel core catcher strategy rather than the IVR strategy. Although the mitigation strategies suggested are vigorously considered, there are still various issues due to its uncertainties and complex phenomena during severe accidents. In this study, to assess the effect of studs installed on the core catcher body, a CFD analysis for coolant channels having rectangular or cylinder shaped studs is carried out. In this study, numerical simulations for the different stud shapes of the core catcher system were carried out using ANSYS FLUENT. For a comparison work, the rectangular and cylinder shaped stud were modeled with the same initial and boundary conditions. The major findings observed from this study can be summarized as follows. - The simulation results showed the 31% reduced amount of pressure drop for the case of the cylinder shaped studs as compared with the reference case, which is for the rectangular studs. - The tendency of reduced pressure drop is well in accord with the flow distribution. The fluid velocities around the studs were greatly distorted for the rectangular studs than those around the cylinder studs. - The distorted stream of fluid could affect heat transfer from core catcher body, and result in locally additional damages. This result may suggest the necessity of finding an optimized stud shape. For more improved comparison work, an additional simulation is planned including different stud shapes.

Studded and unstudded winter tires in fatal road accidents in Finland.

Science.gov (United States)

Malmivuo, Mikko; Luoma, Juha; Porthin, Markus

2017-07-04

The aim of the study was to compare the safety effects of studded and unstudded winter tires based on fatal road accidents. The data included 958 road accidents involving a passenger car or van that occurred in Finland from November to March between 1997 and 2012. Comparing the proportions of winter tire type in accidents and in general traffic showed that the overall effect of tire type on the number of accidents was not significant, although studded tires reduced fatal accidents by 10-15%. Compared to unstudded tires, studded tires reduced accidents significantly only on bald ice in 2005-2012. Drivers using unstudded tires were more experienced and their profession was more frequently related to driving. In addition, the vehicle age was lower for vehicles with unstudded tires. On the other hand, the state of repair was less pertinent for unstudded than for studded tires. These confounding factors offset their effects to some degree. The risk of fatal road accidents in winter between studded and unstudded tires does not differ significantly. However, the accident risk has recently been substantially higher on bald ice for unstudded than for studded tires. The magnitude of this risk difference is difficult to determine without specific information on exposure by road surface.

Development of steel head joints with fiberglass sucker rod on the base of contact stresses investigation

Energy Technology Data Exchange (ETDEWEB)

Kopey, B.V.; Kopey, L.B. [Ivano-Frankivsk State Technical Oil and Gas University (Ukraine); Maksymuk, A.V.; Shcherbyna, N.M. [National Ukrainian Academy of Sciences (Ukraine)

1998-12-31

The methods of calculation of contact stresses during cylinder shell tube - steel bandage interaction are presented. Tymoshenko`s generalized theory of shells serves as a basis for investigating steel head to fiberglass sucker rod joint strength. This theory allows to consider mechanical performance of composite materials. The problem is reduced to solving Fredholm integral equation of second degree. The numeric analysis is performed. Several joints of composite body with steel head are proposed. The full-size sucker rod fatigue tests are performed to determine the fatigue limit under the bending and axial cyclic loads in the medium of oil well fluids. (orig.)

The corrosion resistance of materials used for the manufacture of ear piercing studs

International Nuclear Information System (INIS)

Correa, O. V.; Saiki, M.; Rogero, S. O.; Costa, I.

2003-01-01

Nickel containing alloy shave been widely used as substrates for the manufacture of studs used for ear piercing. Unfortunately, nickel has also been related to the development of allergic contact dermatitis caused by skin sensitization due to Ni''2+ ions. Nickel ions can be leached out into the body fluids due to corrosion reactions. Defect free coatings are very difficult to produce, and therefore nickel free materials should be used as substrates of ear piercing studs, although the commercial alloys used usually contain this element. In this study, the corrosion resistance of two kinds of commercial studs prepared with nickel containing substrates and a titanium laboratory made stud was determined in a culture medium. The corrosion resistance of the studs was investigated by means of potentiodynamic polarization tests and electrochemical impedance spectroscopy as a function of immersion time in the culture medium. The elements that leached out into the medium due to corrosion reactions were analyzed by instrumental neutron activation analysis. The surfaces of the commercial gold-coated studs were examined by scanning electron microscopy and analyzed by energy dispersive spectroscopy, both before and after exposure to the culture medium. The cytotoxicity of the tested studs was also determined in the culture medium. (Author) 10 refs

Implementation of STUD Pulses at the Trident Laser and Initial Results

Science.gov (United States)

Johnson, R. P.; Shimada, T.; Montgomery, D. S.; Afeyan, B.; Hüller, S.

2012-10-01

Controlling and mitigating laser-plasma instabilities such as stimulated Brillouin scattering, stimulated Raman scattering, and crossed-beam energy transfer is important to achieve high-gain inertial fusion using laser drivers. Recent theory and simulations show that these instabilities can be largely controlled using laser pulses consisting of spike trains of uneven duration and delay (STUD) by modulating the laser on a picosecond time scale [1,2]. We have designed and implemented a STUD pulse generator at the LANL Trident Laser Facility using Fourier synthesis to produce a 0.5-ns envelope of psec-duration STUD pulses using a spatial light modulator. Initial results from laser propagation tests and measurements as well as initial laser-plasma characterization experiments will be presented.[4pt] [1] B. Afeyan and S. H"uller, ``Optimal Control of Laser Plasma Instabilities using STUD pulses,'' IFSA 2011, P.Mo.1, to appear in Euro. Phys. J. Web of Conf. (2012).[2] S. H"uller and B. Afeyan, ``Simulations of drastically reduced SBS with STUD pulses,'' IFSA 2011, O.Tu8-1, to appear in Euro. Phys. J. Web of Conf. (2012).

Alloy-steel bolting materials for special applications

International Nuclear Information System (INIS)

Anon.

1981-01-01

This specification covers regular and special-quality alloy steel bolting materials which may be used for nuclear and other special applications. Bolting materials as used in the specification cover rolled or forged bars, rotary pierced or extruded seamless tubes, bored bars, or forged hollows from forged or rolled bar segments to be machined into bolts, studs, washers, and nuts. Several grades of steel are covered and supplementary requirements of an optional nature are provided for use when special quality is desired

Reactor Structural Materials: Reactor Pressure Vessel Steels

International Nuclear Information System (INIS)

Chaouadi, R.

2000-01-01

The objectives of SCK-CEN's R and D programme on Rector Pressure Vessel (RPV) Steels are:(1) to complete the fracture toughness data bank of various reactor pressure vessel steels by using precracked Charpy specimens that were tested statically as well as dynamically; (2) to implement the enhanced surveillance approach in a user-friendly software; (3) to improve the existing reconstitution technology by reducing the input energy (short cycle welding) and modifying the stud geometry. Progress and achievements in 1999 are reported

Finite element modelling for thermal analysis of stud-to-plate laser brazing for a dissimilar metal joint

International Nuclear Information System (INIS)

Park, Jun Soo; Kim, Jong Min

1996-06-01

A finite element model was developed for the thermal analysis of a stud-to-plate laser brazing joint, and the transient temperature fields were analysed by using a three-dimensional model. The finite element program ABAQUS, together with a few user subroutines, was employed to perform the numerical approximation. Temperature-dependent thermal properties, effect of latent heat, and the convection and radiative heat losses were considered. The brazing parts used were AISI 304 stainless steel stud and aluminium A1 5052 plate, and the brazing alloy 88 A1-12 Si was used as filler metal. A pseudo-TM 01 mode of the cw CO 2 laser beam was used as heat source, for which TM 00 mode generated by beam oscillator was optically modulated using axicon lens. Re-location of the filler metal during the brazing process including its wetting and spreading was examined by using a high speed motion analyser, and the results were incorporated inn the FEM modelling for defining the solution domain and boundary conditions. The numerical results were obtained for typical process parameters, and were compared with experimental ones determined by using the infrared and thermocouple measurements. 11 figs., 30 refs. (Author)

Stud-bolts strength for cell-liner design under shearing deformation

International Nuclear Information System (INIS)

Watashi, Katsumi; Nakanishi, Seiji

1991-01-01

This paper presents experimental and analytical stud-bolt strength subjected to large shearing deformation at high temperature. Tensile test result of the material, SM41B, was shown in the range of room temperature to 550degC at 10 -3 and 10 -4 m/m/s in strain rate. Shearing fracture test result of the stud-bolt is shown at room temperature and 530degC. Shearing fracture criterion was discussed based on both test results and FEM analysis result. (author)

Probing electronic interactions using electron tunneling

Indian Academy of Sciences (India)

pratap

Sample preparation. Chamber. Sample manipulators. Vibration Isolation. Table. Cryostat. Load lock. STM Head. Magnet. Sample holder. Tip. Tip holder. Piezo electric tube. Coarse positioner. Macor. Cu housing for sample holder. PCB. Cu shielding can. Steel studs. Our Toy: The TIFR milli-Kelvin STM. Lowest temperature:.

Detection of stress corrosion cracks and wastage in reactor pressure vessels and primary coolant system studs

International Nuclear Information System (INIS)

Light, G.M.; Joshi, N.R.

1986-01-01

Over the last few years, nuclear plants have experienced stud bolt failures due to stress corrosion cracking and corrosion wastage. Many of these stud bolts were over 1 m long and had no heater hole. The use of conventional longitudinal wave inspection for bolts longer than 1 m has shown inconsistent results. A nondestructive testing technique was needed to inspect the stud bolts in place. The cylindrically guided wave technique was developed to inspect stud bolts of various lengths (up to 3 m) and various diameters. This technique is based on the fact that an ultrasonic wave traveling in a long cylinder becomes guided by the geometry of the cylinder. The wave begins to spread in the cylinder as interaction with the outer wall produces mode conversions. A large number of model stud bolts were tested to verify that the cylindrically guided wave technique could be used to detect crack-like defects and simulated corrosion wastage. This work shows that the cylindrically guided wave technique can be used on a wide variety of stud bolt configurations, and that the technique can be used to effectively detect the two most common modes of stud bolt failure (corrosion cracking and corrosion wastage) at early stages of development

Investigation of Shear Stud Performance in Flat Plate Using Finite Element Analysis

Directory of Open Access Journals (Sweden)

T.S. Viswanathan

2014-09-01

Full Text Available Three types of shear stud arrangement, respectively featuring an orthogonal, a radial and a critical perimeter pattern, were evaluated numerically. A numerical investigation was conducted using the finite element software ABAQUS to evaluate their ability to resist punching shear in a flat plate. The finite element analysis here is an application of the nonlinear analysis of reinforced concrete structures using three-dimensional solid finite elements. The nonlinear characteristics of concrete were achieved by employing the concrete damaged plasticity model in the finite element program. Transverse shear stress was evaluated using finite element analysis in terms of shear stress distribution for flat plate with and without shear stud reinforcement. The model predicted that shear studs placed along the critical perimeter are more effective compared to orthogonal and radial patterns.

Vehicle non-exhaust emissions from the tyre-road interface - effect of stud properties, traction sanding and resuspension

Science.gov (United States)

Kupiainen, Kaarle J.; Pirjola, Liisa

2011-08-01

In Northern cities respirable street dust emission levels (PM 10) are especially high during spring. The spring time dust has been observed to cause health effects as well as discomfort among citizens. Major sources of the dust are the abrasion products from the pavement and traction sand aggregates that are formed due to the motion of the tyre. We studied the formation of respirable abrasion particles in the tyre-road interface due to tyre studs and traction sanding by a mobile laboratory vehicle Sniffer. The measurements were preformed on a test track, where the influence of varying stud weight and stud number per tyre on PM 10 emissions was studied. Studded tyres resulted in higher emission levels than studless tyres especially with speeds 50 km h -1 and higher; however, by using light weight studs, which approximately halves the weight of studs, or by reducing the number of studs per tyre to half, the emission levels decreased by approximately half. Additionally measurements were done with and without traction sand coverage on the pavement of a public road. After traction sanding the emission levels were not affected by tyre type but by formation and suspension of traction sand related dust from the road surface. The emissions after traction sanding decreased as a function of time as passing vehicles' motion shifted the sand grains away from the areas with most tyre-road contact.

Effects of studded tires on roadside airborne dust pollution in Niigata, Japan

Science.gov (United States)

Fukuzaki, Norio; Yanaka, Takaaki; Urushiyama, Yoshio

Two series of dust samples, collected by Andersen impactors (denoted by AN) and low-volume air samplers (denoted by LV), were investigated with respect to roadside airborne dusts collected in two different periods in 1983. These were the periods (i) with studded tires (February and March) and (ii) without studded tires (October). Multi-element determinations of these samples were made by neutron activation analysis and atomic absorption spectrometry. The total concentration of AN in roadside air for period (i) was about three times higher than for the period without studded tires. The lithophilic elements such as Na, Al, K, Ca, Ti, Fe and Th, and component-metal elements of stud tip, W and Ta, produced a significant increase in atmospheric concentration in winter. The contribution of pavement material, one of the most interesting components of airborne particles in this study, was related to total AN and LV by the chemical element balance method. It made up only 16 percent (9.1 μgm -3) of AN in October, compared with 46 percent (70.2 μgm -3) in February. It was also observed that the atmospheric concentrations of pavement debris to total LV decreased with the distance from the road to each sampling site.

Measure Guideline: Deep Energy Enclosure Retrofit for Double-Stud Walls

Energy Technology Data Exchange (ETDEWEB)

Loomis, H. [Building Science Corporation, Westford, MA (United States); Pettit, B. [Building Science Corporation, Westford, MA (United States)

2015-06-01

This Measure Guideline describes a deep energy enclosure retrofit (DEER) solution that provides insulation to the interior of the wall assembly with the use of a double stud wall. The guide describes two approaches to retrofitting the existing the walls: one involving replacement of the existing cladding, and the other that leaves the existing cladding in place. It discusses the design principles related to the use of various insulation types, and provides strategies and procedures for implementing the double stud wall retrofit. It also evaluates important moisture-related and indoor air quality measures that need to be implemented to achieve a durable, high performance wall.

Measure Guideline: Deep Energy Enclosure Retrofit for Double-Stud Walls

Energy Technology Data Exchange (ETDEWEB)

Loomis, H. [Building Science Corporation, Westford, MA (United States); Pettit, B. [Building Science Corporation, Westford, MA (United States)

2015-06-22

This Measure Guideline describes a deep energy enclosure retrofit solution that provides insulation to the interior of the wall assembly with the use of a double-stud wall. The guide describes two approaches to retrofitting the existing walls—one that involves replacing the existing cladding and the other that leaves the cladding in place. This guideline also covers the design principles related to the use of various insulation types and provides strategies and procedures for implementing the double-stud wall retrofit. It also includes an evaluation of important moisture-related and indoor air quality measures that need to be implemented to achieve a durable high-performance wall.

Application of neutron activation analysis to the corrosion study of gold coated studs used for piercing ears

International Nuclear Information System (INIS)

Saiki, M.; Rogero, S.O.; Costa, I.; Correa, O.V.; Higa, O.Z.

1998-01-01

Complete text of publication follows. Gold is known as a metal having little or no toxicity and it has been widely used for coating studs for ear piercing. However, for some people gold coated studs have caused serious allergy and inflammation problems. After piercing, the studs are usually kept in the ear lobes for at least one week, and during this period the stud surfaces in contact with the body fluids have caused swelling, pain and redness of the skin. Consequently, it is of great interest to evaluate if elements from the metallic substrate underneath the gold coatings migrate to the body fluids due to the corrosion and the presence of defects in gold coatings. The solutions for corrosion test were obtained by placing the gold coated studs in contact with the solutions of NaCl and of culture medium. Elemental analyses of these solutions by radioanalytical method of neutron activation analysis indicated the occurrence of substrate corrosion since the elements Cr, Fe, Ni and Zn were found in these solutions. These elements are substrate material components of alloys used to make the studs and they were quantified by X-ray fluorescence analysis. The defects of the coatings were also detected by scanning electron microscopy and energy dispersive spectroscopy analysis of the gold coated studs before and after the corrosion tests. Cytotoxicity studies indicated that after corrosion test the solution used was toxic in the culture cell assay. Among the elements quantified in the test solutions, Ni is considered responsible for most of allergic reactions. Results obtained in this work indicated the necessity to improve quality control of the coating process of studs and in the appropriate choice of material used as substrate

Development of plastic media blasting device for stud bolt

International Nuclear Information System (INIS)

Yoshihisa, Y.; Miyashita, T.

1999-01-01

Plastic media blasting is a mechanical cleaning method for removing paint, rust and/or anti-galling material etc on the surface of metal without damaging the metal surface. The method is suitable for cleaning the surface of reusable elements and parts such as bolts and nuts. Anti-galling material such as molybdenum disulfide is applied to fastening stud bolts used for the steam turbine rotor casing. It is necessary to remove this material when new anti-galling material is to be applied. Genden Engineering Services and Construction Co., and Morikawa Industries Corp., have developed a plastic media blasting device to clean the surface of stud bolt screw threads installed in the facility such as lower casing of the turbine. This paper reports the outline of the results. (author)

Enhancement of crack detection in stud bolts of nuclear reactor by ultrasonic signal processing technique

International Nuclear Information System (INIS)

Lee, J.H.; Oh, W.D.; Choi, S.W.; Park, M.H.

2004-01-01

'Full-text:' The stud bolts is one of the most critical parts for safety of reactor vessels in the nuclear power plants. However, in the application of ultrasonic technique for crack detection in stud bolt, some difficulties encountered are classification of crack signal from the signals reflected from threads part in stud bolt. In this study, shadow effect technique combined with new signal processing method is Investigated to enhance the detectability of small crack initiated from root of thread in stud bolt. The key idea of signal processing is based on the fact that the shape of waveforms from the threads is uniform since the shape of the threads in a bolt is same. If some cracks exist in the thread, the flaw signals are different to the reference signals. It is demonstrated that the small flaws are efficiently detected by novel ultrasonic technique combined with this new signal processing concept. (author)

Current state of knowledge on the behavior of steel liners in concrete containments subjected to overpressurization loads

International Nuclear Information System (INIS)

von Riesemann, W.A.; Parks, M.B.

1993-01-01

In the United States, concrete containment buildings for commercial nuclear power plants have steel liners that act as the intemal pressure boundary. The liner abuts the concrete, acting as the interior concrete form. The liner is attached to the concrete by either studs or by a continuous structural shape (such as a T-section or channel) that is either continuously or intermittently welded to the liner. Studs are commonly used in reinforced concrete containments, while prestressed containments utilize a structural element as the anchorage. The practice in some countries follows the US practice, while in other countries the containment does not have a steel liner. In this latter case, there is a true double containment, and the annular region between the two containments is vented. This paper will review the practice of design of the liner system prior to the consideration of severe accident loads (overpressurization loads beyond the design conditions)

Computerized UT system for stud bolt

International Nuclear Information System (INIS)

Kisanuki, T.; Uchida, K.; Fushimi, T.; Onda, K.

1988-01-01

Cracking of stud bolts used in steam turbine casing, valve and pressure vessel has caused concern regarding the safety and reliability of power plants. In order to detect harmful cracks in early state, the improvement of UT technique is required. As regarding the ultrasonic inspection technique, a longitudinal beam technique and/or an angle beam technique are generally used. The authors report their development of a computerized UT system for bolt inspection and improvement of the angle beam technique

A Parameter Study of Coupling Properties in Finite Element Models of Single-Stud Double-Plate Panels

DEFF Research Database (Denmark)

Dickow, Kristoffer Ahrens; Domadiya, Parthkumar Gandalal; Andersen, Lars Vabbersgaard

2011-01-01

Lightweight building techniques are currently progressing fast and using such structures for multi-storey multi-family dwellings is becoming part of the industry standard. Partitions in lightweight buildings are often constructed as plates on frame structures made of either wood or steel. In any...... case the low frequency sound transmission is often an issue that needs attention. The present paper utilizes a finite element model of a single-stud double-plate panel structure to investigate how different couplings between the plates and the frame structure affect the direct sound transmission. Four...... different coupling configurations are considered: 1) All structural contact points are completely tied; 2) only nodes on the centre lines of the structure are tied; 3) a narrow strip of tied elements connect the frame to the plates; 4) evenly spaced discrete elements are tied. In all cases the interaction...

High-temperature drying of 7/4 yellow-poplar flitches for S-D-R studs

Science.gov (United States)

R. Sidney Boone; Robert R. Maeglin

1980-01-01

Yellow-poplar was dried as 7/4 flitches at high temperatures and subsequently ripped into studs to meet National Grading Rule Standards for STUD grade. The effects of growth stresses in these flitches from smaller logs appear to be minimized by this process. Dry bulb temperatures from 235° to 295° F were explored in five drying trials. Best results were by drying for...

Effect of Steel Framing for Securing Drywall Panels on Thermal and Humidity Parameters of the Outer Walls

Science.gov (United States)

Major, Maciej; Kosiń, Mariusz

2017-12-01

The paper analyses the effect of steel framing used to secure drywall panels on thermal and humidity properties of outer walls. In the practice of building a light structure, the most popular components are steel and wood studs. They are used to obtain framing for building a wall (an outer wall in this study). Analysis presented in this study concerned the corner of the outer wall build using the technology of light steel framing. Computer simulation was used to perform thermal and humidity analysis for the joint of the outer wall.

Effect of Steel Framing for Securing Drywall Panels on Thermal and Humidity Parameters of the Outer Walls

Directory of Open Access Journals (Sweden)

Major Maciej

2017-12-01

Full Text Available The paper analyses the effect of steel framing used to secure drywall panels on thermal and humidity properties of outer walls. In the practice of building a light structure, the most popular components are steel and wood studs. They are used to obtain framing for building a wall (an outer wall in this study. Analysis presented in this study concerned the corner of the outer wall build using the technology of light steel framing. Computer simulation was used to perform thermal and humidity analysis for the joint of the outer wall.

Effects on accidents of changes in the use of studded tyres in major cities in Norway

DEFF Research Database (Denmark)

Elvik, Rune; Fridstrøm, Lasse; Kaminska, Joanna

2013-01-01

This paper reports the findings of two studies made eleven years apart in Norway (0035 and 0025) to evaluate effects on accidents of changes in the use of studded tyres in major cities in Norway. The first study covered the period from 1991 to 2000, the second study covered the period from 2002...... to 2009. In both these periods, large changes in the percentage of cars using studded tyres were found in the cities that were included in the study. There was, in most cities, a tendency for the use of studded tyres to go down. Effects of these changes on injury accidents were evaluated by means...... of negative binomial regression models, using city and day as the unit of analysis, and including more than twenty explanatory variables in order to control for confounding factors. The effects of changes in the percentage of cars using studded tyres were well described by an accident modification function...

Failure analysis of the stud bolt of a canned motor pump of heavy water plant, Talcher

International Nuclear Information System (INIS)

Kumar, Sunil; Sethumadhavan, V.; Sah, D.N.; Sivaramakrishnan, K.S.; Kain, Vivekanand; Gadiyar, H.S.

1990-01-01

Detailed investigations have been carried out on the failed stud bolts (made of DIN 1.4021 X 20Cr 13) of a canned motor pump of Heavy Water Plant, Talcher, using metallographic, microhardness testing, scanning electron microscopy and electron probe micro-analysis(EPMA) techniques. The studs had failed in a brittle manner in the mid-length portion. The origin of the fracture has been identified to be a corroded region on the stud surface. Branching cracks propagating through silicon rich inclusions have been noted. Two types of inclusions, one containing Mn and S and other containing S, Mn and O 2 have been found in the material. Clusters of large and small inclusions of the above types have been found near the origin of the fracture. It has been concluded that the fracture was caused by corrosion fatigue, initiating at the cluster of inclusions present on the surface of the stud bolts. (author). 7 refs., 5 figs

Feasibility of Steel Fiber-Reinforced Rubberized Concrete in Cold Regions for High Volume Intersections

Science.gov (United States)

Abou Eid, Mahear A.

There are many challenges faced with the use of Portland Cement Concrete (PCC) in cold regions, but with the inclusion of new technologies such as steel fibers and recycled tire crumb rubber efficient construction may be possible. Research was conducted on a modified concrete material that included both steel fibers and crumb rubber. The composite material was called Steel Fiber-Reinforced Rubberized Concrete (SFRRC). The objective of this investigation was to provide evidence showing that SFRRC can reduce tire rutting compared to asphaltic pavement. In addition, the research showed that the SFRRC could withstand freeze-thaw cycles and increase service life of roadways. Several tests were performed to determine the characteristics of the material. Freeze-thaw testing was performed to determine compressive strength loss and visual deterioration of the material. Wheel tracker rut testing was performed both with the standard steel wheel and with a modified studded rubber tire to determine plastic deformation and rut resistance. An experimental test slab was cast in place on a public approach to observe the construction procedures, the effects of studded tire wear and the frost actions in cold region conditions. Based on freeze-thaw and wheel tracker test results and observations of the experimental test slab, the SFRRC material shows viability in cold regions for resisting freeze-thaw actions. The freeze-thaw testing resulted in increased compressive strength after 300 freeze-thaw cycles and very low deterioration of material compared to standard PCC. The wheel tracker testing resulted in very low plastic deformation and minor material rutting with use of the studded rubber tire. The test slab showed very minor surface wear, no freeze-thaw cracking and no rutting after one winter of use. It is recommended that further testing of the material be conducted by means of a large-scale trial section. This would provide information with respect to cost analysis and

[Energy intake and body weight development of Warmblood foals that changed stud at weaning].

Science.gov (United States)

Mack, J K; Remler, H P; Senckenberg, E; Kienzle, E

2014-01-01

This study investigated the energy requirements of Warmblood foals with a change of the stud at weaning. Nine colts purchased at weaning participated in the study aged approximately 6 months to 1 year. They were transported to the stud by their breeders either having been separated from their dams in their home stable or upon arrival at the stud. The foals were offered a late first cut of haylage, oats and foal starter feed. To ensure individual feeding of concentrates, the foals were tethered twice daily. The total combined haylage intake of all foals per day was recorded. Individual concentrate intake, body weight and body condition score (BCS) were documented at 4-week intervals. The total energy intake was 74 MJ digestible energy (68 MJ metabolisable energy) per animal per day. The foals had been delivered at the stud with a comparably low body weight (285 ± 30 kg) and BCS (4.2 ± 0.4 on a scale from 1 to 9). At the end of the study, aged 319 ± 22 days, they attained an average body weight of 326 ± 24 kg and a BCS of 4.2 ± 0.4. The energy intake of the foals of this study was higher and their body weight development slower than in foals of a parallel study, which were born and raised in the stud and therefore exposed to less stressful weaning conditions. Foals with a comparatively low body weight and BCS at weaning in combination with further stressors need considerably more energy than foals that undergo less stressful weaning conditions.

Modelling road dust emission abatement measures using the NORTRIP model: Vehicle speed and studded tyre reduction

Science.gov (United States)

Norman, M.; Sundvor, I.; Denby, B. R.; Johansson, C.; Gustafsson, M.; Blomqvist, G.; Janhäll, S.

2016-06-01

Road dust emissions in Nordic countries still remain a significant contributor to PM10 concentrations mainly due to the use of studded tyres. A number of measures have been introduced in these countries in order to reduce road dust emissions. These include speed reductions, reductions in studded tyre use, dust binding and road cleaning. Implementation of such measures can be costly and some confidence in the impact of the measures is required to weigh the costs against the benefits. Modelling tools are thus required that can predict the impact of these measures. In this paper the NORTRIP road dust emission model is used to simulate real world abatement measures that have been carried out in Oslo and Stockholm. In Oslo both vehicle speed and studded tyre share reductions occurred over a period from 2004 to 2006 on a major arterial road, RV4. In Stockholm a studded tyre ban on Hornsgatan in 2010 saw a significant reduction in studded tyre share together with a reduction in traffic volume. The model is found to correctly simulate the impact of these measures on the PM10 concentrations when compared to available kerbside measurement data. Importantly meteorology can have a significant impact on the concentrations through both surface and dispersion conditions. The first year after the implementation of the speed reduction on RV4 was much drier than the previous year, resulting in higher mean concentrations than expected. The following year was much wetter with significant rain and snow fall leading to wet or frozen road surfaces for 83% of the four month study period. This significantly reduced the net PM10 concentrations, by 58%, compared to the expected values if meteorological conditions had been similar to the previous years. In the years following the studded tyre ban on Hornsgatan road wear production through studded tyres decreased by 72%, due to a combination of reduced traffic volume and reduced studded tyre share. However, after accounting for exhaust

Behaviour of steel-concrete composite beams using bolts as shear connectors

Science.gov (United States)

Tran, Minh-Tung; Nguyen Van Do, Vuong; Nguyen, Tuan-Anh

2018-04-01

The paper presents an experimental program on the application of bolts as shear connectors for steel-composite beams. Four steel- concrete composite beams and a reference steel beam were made and tested. The aim of the testing program is to examine which forms of the steel bolts can be used effectively for steel-composite beams. The four types of the bolts include: Type 1 the bolt with the nut at the end; Type 2 the bolt bending at 900 hook; Type 3 the bolt without the nut at the end and Type 4 the bolt with the nut at the end but connected with the steel beam by hand welding in other to be connected with the steel beam by bolt connection as in the first three types. The test results showed that beside the traditional shear connectors like shear studs, angle type, channel type, bolts can be used effectively as the shear connectors in steel-composite beams and the application of bolts in Types 1 and 2 in the composite beams gave the better performance for the tested beam.

Ultrasonic measurement on RPV stud-bolt loading under hot transient of Qinshan NPP

International Nuclear Information System (INIS)

Qu Jiadi; Dou Yikang; Zhu Shiming; Lu Jie; Wang Yingguan

1994-01-01

It is a continuation of research work for sealing analysis and tests on the PRV of PWR. It expounds that the key of solving thermal transient sealing problem lies in giving the thermal increment of stud-bolt fatigue life and transient loading spectrum for vessel analysis. The authors recounted the fundamental works and main results of ultrasonic measurement on RPV stud-bolt loading on the reactor of Qinshan Nuclear Power Plant. The measuring capability exceeds 1 m length and 300 degree C temperature. Therefore, it is possible to be used in the field of NPP

Calcification of intervertebral discs in the dachshund: a radiographic study of 21 stud-dogs

International Nuclear Information System (INIS)

Stigen, O.

1995-01-01

The vertebral columns of 21 clinically normal, 4.9 to 13.2 year old dachshunds were x-rayed. This sample represented 55.3% of all male dachshunds with 20 or more offspring registered with the Norwegian Kennel Club in the period 1985-1989. Calcified intervertebral discs were identified in 9 (42.9%) of the stud-dogs, and the number of calcified discs in each individual varied from 2 to 5 with a mean of 3.7. The frequency of stud-dogs with 1 or more calcified discs was compared with the corresponding frequency in a material of 327 one-year-old dachshunds. In this comparison, the relative risk was estimated with 95% confidence bounds. When the different composition of size and coat varieties in the 2 materials was not considered, the relative risk of calcified discs was found to be 1.77 (0.99-3.2) times higher in stud-dogs than in young dogs. When the different composition of varieties in the 2 materials was considered, the relative risk was found to be 1.9 (1.1-3.4) times higher in stud-dogs than in young dogs. The results of the present study strongly suggest that an increase in the frequency of dachshunds with 1 or more calcified intervertebral discs occurs after 1 year of age

Common Cause Case Study: An Estimated Probability of Four Solid Rocket Booster Hold-Down Post Stud Hang-ups

Science.gov (United States)

Cross, Robert

2005-01-01

Until Solid Rocket Motor ignition, the Space Shuttle is mated to the Mobil Launch Platform in part via eight (8) Solid Rocket Booster (SRB) hold-down bolts. The bolts are fractured using redundant pyrotechnics, and are designed to drop through a hold-down post on the Mobile Launch Platform before the Space Shuttle begins movement. The Space Shuttle program has experienced numerous failures where a bolt has hung up. That is, it did not clear the hold-down post before liftoff and was caught by the SRBs. This places an additional structural load on the vehicle that was not included in the original certification requirements. The Space Shuttle is currently being certified to withstand the loads induced by up to three (3) of eight (8) SRB hold-down experiencing a "hang-up". The results of loads analyses performed for (4) stud hang-ups indicate that the internal vehicle loads exceed current structural certification limits at several locations. To determine the risk to the vehicle from four (4) stud hang-ups, the likelihood of the scenario occurring must first be evaluated. Prior to the analysis discussed in this paper, the likelihood of occurrence had been estimated assuming that the stud hang-ups were completely independent events. That is, it was assumed that no common causes or factors existed between the individual stud hang-up events. A review of the data associated with the hang-up events, showed that a common factor (timing skew) was present. This paper summarizes a revised likelihood evaluation performed for the four (4) stud hang-ups case considering that there are common factors associated with the stud hang-ups. The results show that explicitly (i.e. not using standard common cause methodologies such as beta factor or Multiple Greek Letter modeling) taking into account the common factor of timing skew results in an increase in the estimated likelihood of four (4) stud hang-ups of an order of magnitude over the independent failure case.

The corrosion resistance of materials used for the manufacture of ear piercing studs

Directory of Open Access Journals (Sweden)

Correa, O. V.

2003-12-01

Full Text Available Nickel containing alloys have been widely used as substrates for the manufacture of studs used for ear piercing. Unfortunately, nickel has also been related to the development of allergic contact dermatitis caused by skin sensitization due to Ni²⁺ ions. Nickel ions can be leached out into the body fluids due to corrosion reactions. Defect free coatings are very difficult to produce, and therefore nickel free materials should be used as substrates of ear piercing studs, although the commercial alloys used usually contain this element. In this study, the corrosion resistance of two kinds of commercial studs prepared with nickel containing substrates and a titanium laboratory made stud was determined in a culture medium. The corrosion resistance of the studs was investigated by means of potentiodynamic polarization tests and electrochemical impedance spectroscopy as a function of immersion time in the culture medium. The elements that leached out into the medium due to corrosion reactions were analyzed by instrumental neutron activation analysis. The surfaces of the commercial gold-coated studs were examined by scanning electron microscopy and analyzed by energy dispersive spectroscopy, both before and after exposure to the culture medium. The cytotoxicity of the tested studs was also determined in the culture medium.

Aleaciones conteniendo níquel se han utilizado como substratos para la fabricación de aretes perforantes para orejas. Desafortunadamente, el níquel ha sido relacionado con el desarrollo de una reacción alérgica conocida como dermatitis de contacto, causada por la sensibilización debido a los iones de Ni²⁺. Estos iones pueden ser liberados hacia los fluidos corporales debido a las reacciones de corrosión. Los aretes, habitualmente, se revisten con películas de oro. Sin embargo, es muy difícil hacer los revestimientos libres de defectos superficiales. Por lo tanto, materiales sin níquel deber

Modelling and use of the STUDS nuclear power plant simulator

International Nuclear Information System (INIS)

Blomberg, P.E.; Espefaelt, R.; Josefsson, R.; Schuch, N.

1979-02-01

The simulator models, belonging to the STUDS-family, which have been developed at Studsvik in cooperation with the Swedish utilities, are briefly described. The scope of the simulation is presented and the fundamental equations used are indicated. Different needs have led to a number of STUDS-versions for BWR and PWR type plants, primarily intended for application in the following fields: 1) transient analysis, 2) system design verification, 3) control system development, 4) testing of new on-line techniques for disturbance analysis, noise analysis, man-machine communication, etc, 5) training of power plant operators, 6) operational planning. The simulator was initially implemented on a hybrid computer system but more recent work has led to pure digital simulations maintaining the real time feature and adding features like snapshot and backtrack. The latest version for PWR is used at the Halden Project and in the general purpose COMPACT SIMULATOR: developed at Studsvik and made commercially available. (author)

Genetic diversity in selected stud and commercial herds of the ...

African Journals Online (AJOL)

The Afrikaner is one of three indigenous cattle breeds found in South Africa. Afrikaner cattle were originally extensively used for crossbreeding purposes and breed development. The objective of this study was to determine the genetic diversity of selected stud and commercial herds from the whole South African Afrikaner ...

Stud arc welding in a magnetic field – Investigation of the influences on the arc motion

International Nuclear Information System (INIS)

Hartz-Behrend, K; Forster, G; Schein, J; Marqués, J L; Jenicek, A; Müller, M; Cramer, H; Jilg, A; Soyer, H

2014-01-01

Stud arc welding is widely used in the construction industry. For welding of studs with a diameter larger than 14 mm a ceramic ferrule is usually necessary in order to protect the weld pool. Disadvantages of using such a ferrule are that more metal is molten than necessary for a high quality welded joint and that the ferrule is a consumable generally thrown away after the welding operation. Investigations show that the ferrule can be omitted when the welding is carried out in a radially symmetric magnetic field within a shielding gas atmosphere. Due to the Lorentz force the arc is laterally shifted so that a very uniform and controlled melting of the stud contact surface as well as of the work piece can be achieved. In this paper a simplified physical model is presented describing how the parameters welding current, flux density of the magnetic field, radius of the arc and mass density of the shielding gas influence the velocity of the arc motion. The resulting equation is subsequently verified by comparing it to optical measurements of the arc motion. The proposed model can be used to optimize the required field distribution for the magnetic field stud welding process

ATTEMPTS FOR OPTIMIZATION THE GENETIC IMPROVEMENT ACTIONS IN HORSE POPULATIONS OF NONIUS VARIETY AND ARDENNES BREED FROM THE IZVIN STUD, TIMIŞ COUNTY

Directory of Open Access Journals (Sweden)

D. DRONCA

2007-10-01

Full Text Available Researches were carried out on horse populations of Nonius variety and Ardennes breedfrom Izvin Stud, farm that belongs to the Forestry Direction Timiş. In Romania, Noniusvariety built up at the Mezohegyes Stud in Hungary was imported at Bonţida and Ruşeţu inyear 1920. In year 1940, the two types of Nonius were blended and were raised together atthe Parţa Stud, called later Pădureni Stud. There stayed until year 1967 when the horsepopulation was moved to the Izvin Stud, where is raised together with the Ardennes horseimported from Hungary as well. The aim of the present study was to attempt to optimize thegenetic improvement actions of the horse population from Nonius variety and Ardennesbreed raised at the Izvin Stud. For Nonius variety the main genetic improvement objectiveswere set up as being the improvement of the reproduction traits, correction of the gait inhorses, increasing the energetic capacity, temperament and nervous impulse, as well asother conformation traits. For the Ardennes breed the main genetic improvement objectiveswere considered to be the increase of the constitutional strength, correction of the gait andimprovement of the reproduction indices. The study was ended with a number ofconclusions and recommendations.

The effects of studded tires on fatal crashes with passenger cars and the benefits of electronic stability control (ESC) in Swedish winter driving.

Science.gov (United States)

Strandroth, Johan; Rizzi, Matteo; Olai, Maria; Lie, Anders; Tingvall, Claes

2012-03-01

This study set out to examine the effects of studded tires on fatal crashes on roads covered with ice or snow in Sweden and also to investigate the extra benefits of electronic stability control (ESC) during the winter months. Two different studies are presented in this paper. Both studies used an induced exposure approach. In the main study, 369 in-depth studies of fatal crashes with passenger cars were analyzed to determine whether loss-of-control (LOC) had been a major component or not. Only crashes involving cars without ESC and equipped with approved studded or non-studded winter tires were analyzed. The additional study used police-reported crashes that occurred during the winter seasons 2003-2010, involving passenger cars with and without ESC. While police records in Sweden do not include any tire information, it was assumed that most cars involved in crashes during the winter period would be equipped with studded tires. Findings in the main study showed that in 64% of the fatal crashes on roads covered with ice or snow LOC had been a major component. Furthermore, in 82% of LOC crashes, the passenger car over-steered prior to collision. Studded tires were found to have a statistically significant effect of 42% in terms of fatal crash reduction on roads covered with ice or snow, compared to non-studded winter tires. The effect on dry or wet roads in the winter was negative, although statistically non-significant. In the additional study, it was found that ESC further reduced crashes with injuries by 29%. The benefits on severe and fatal crashes were slightly greater (32%), although the lower 95% confidence limit was lower. Although studded tires were shown to reduce the risk of fatal crash involvement, compared to non-studded winter tires, the proportion of LOC and over-steering among cars with studded tires was large (59% and 49%, respectively). It was therefore concluded that studded tires do not prevent all LOC crashes, while ESC has benefits in those

Site ultrasonic measurement on RPV stud-bolt loading under hot transient of Qinshan NPP

International Nuclear Information System (INIS)

Qu Jiadi; Dou Yikang; Zhu Shiming

1994-08-01

It expounds that the key of solving thermal transient sealing problem is to obtain the thermal increment of stud-bolt loading. This loading, as a primary stress loading, is directly related to the bolt fatigue life and transient loading spectrum for vessel analysis. The fundamental works and main results of ultrasonic measurement on RPV stud-bolt loading on Qinshan site are also presented. The measuring capability has exceeded 1 m in length and temperature of 280 degree C, therefore, it is possible to be used in the field of NPP. The paper is the continuation of research work for sealing analysis and tests on the RPV (see SMiRT-9, 10)

Development of Automatic Ultrasonic Testing Equipment for Pressure-Retaining Studs and Bolts in Nuclear Power Plant

International Nuclear Information System (INIS)

Suh, D. M.; Park, M. H.; Hong, S. S.

1989-01-01

Bolting degradation problems in primary coolant pressure boundary applications have become a major concern in the nuclear industry. In the bolts concerned, the failure mechanism was either corrosion wastage(loss of bolt diameter) or stress-corrosion cracking. Here the manual ultrasonic testing of RPV(Reactor Pressure Vessel) and RCP(Reactor Coolant Pump) stud has been performed. But it is difficult to detect indications because examiner can not exactly control the rotation angle and can not distinguish the indication from signals of bolt. In many cases, the critical sizes of damage depth are very small(1-2 mm order). At critical size, the crack tends to propagatecompletly through the bolt under stress, Resulting in total fracture. Automatic stud scanner for studs(bolts) was developed because the precise measurement of bolt diameter is required in this circumstance. By use of this scanner, the rotation angle of probe was exactly controlled and the exposure time of radiations was reduced

Innovation on structure of all automatic multi-studs four synchronous installing machine used in PWR

International Nuclear Information System (INIS)

Zhu Qirong; Zou Xiyang

2002-01-01

First of all from structure bring forth many new ideas. New stud, nut and a brand-new installing machine have been designed. In main machine, the integrated gear mechanism simple in structure achieves synchronous turning function, instead of the precision, complicated, expensive manipulator or robot. In aspect of supervising and controlling, computer electro-hydraulic proportional control and advanced examine measure system have been designed to measure stress and extension of stud as tensioning. Mathematics model and transmit function have been built using theory of modern times fluid transmission and control. As a result four synchronous installing has been achieved

Effects of herd origin, AI stud and sire identification on genetic evaluation of Holstein Friesian bulls

OpenAIRE

Giovanni Bittante; Paolo Carnier; Luigi Gallo Gallo; Riccardo Dal Zotto; Martino Cassandro

2010-01-01

The purpose of this study was to estimate the effects of herd origin of bull, AI stud and sire identification number (ID)  on official estimated breeding values (EBV) for production traits of Holstein Friesian proven bulls. The data included 1,005  Italian Holstein-Friesian bulls, sons of 76 sires, born in 100 herds and progeny tested by 10 AI studs. Bulls were required  to have date of first proof between September 1992 and September 1997, to be born in a herd with at least on...

Changes in United States Advertising 1976-1986 (a la Studs Terkel).

Science.gov (United States)

Jackson, DeForrest; Lamb, Christopher J.

To examine the most important changes in marketing and advertising of the decade from 1976 to 1986, more than 100 people were interviewed, and their responses were fashioned into an oral history modeled on the technique used in Studs Terkel's popular books. Among those interviewed were advertising and marketing professionals, as well as casual…

Examination of failed studs from No. 2 steam generator at the Maine Yankee Nuclear Power Station

International Nuclear Information System (INIS)

Czajkowski, C.

1983-02-01

Three studs removed from service on the primary manway cover from steam generator No. 2 of the Maine Yankee station were sent to Brookhaven National Laboratory (BNL) for examination. The examination consisted of visual/dye penetrant examination, optical metallography and Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS) evaluation. One bolt was through cracked and its fracture face was generally transgranular in nature with numerous secondary intergranular cracks. The report concludes that the environmenally assisted cracking of the stud was due to the interaction of the various lubricants used with steam leaks associated with this manway cover

Screwing or unscrewing device for studs or bolls of big dimension

International Nuclear Information System (INIS)

Sevelinge, G.; Bourdonne, J.C.

1988-01-01

The device for screwing or unscrewing large studs or bolts has a system determining the optimun screwing position and orientation of the bolt, a variable speed bidirectional drive a pin holding the bolt axially and system compensating the weight of the bolt with an hydraulic jack with a pressure detector to which the drive is slaved [fr

Remote controlled stud bolt handling device for reactor pressure vessel

International Nuclear Information System (INIS)

Shindo, Takenori; Shigehiro, Katsuya; Ito, Morio; Okada, Kenji

1988-01-01

In nuclear power stations, at the time of regular inspection, the works of opening and fixing the upper covers of reactor pressure vessels are carried out for inspecting the inside of reactor pressure vessels and exchanging fuel rods. These upper covers are fastened with many stud bolts, therefore, the works of opening and fixing require a large amount of labor, and are done under the restricted condition of wearing protective clothings and masks. Babcock Hitachi K.K. has completed the development of a remotely controlled automatic bolt tightenig device for this purpose, therefore, its outline is reported. The conventional method of these works and the problems in it are described. The design of the new device aimed at the parallel execution of cleaning screw threads, loosening and tightening nuts, and taking off and putting on nuts and washers, thus contributing to the shortening of regular inspection period, the reduction of the radiation exposure of workers, and the decrease of the number of workers. The function, reliability and endurance of the new device were confirmed by the verifying test using a device made for trial. The device is composed of a stand, a rail and four stations each with a cleaning unit, a stud tensioner and a nut handling unit. (K.I.)

Current state of knowledge on the behavior of steel liners in concrete containments subjected to overpressurization loads

International Nuclear Information System (INIS)

Riesemann, W.A. von; Parks, M.B.

1995-01-01

In the US, concrete containment buildings for commercial nuclear power plants have steel liners that act as the internal pressure boundary. The liner abuts the concrete, acting as the interior concrete form. The liner is attached to the concrete by either studs or by a continuous structural shape (such as a T-section or channel) that is either continuously or intermittently welded to the liner. Studs are commonly used in reinforced concrete containments, while prestressed containments utilize a structural element as the anchorage. The practice in some countries follows the US practice, while in other countries the containment does not have a steel liner. In this latter case, there is a true double containment, and the annular region between the two containments is vented.This paper will review the practice of design of the liner system prior to the consideration of severe accident loads (overpressurization loads beyond the design conditions).An overpressurization test of a 1:6 scale reinforced concrete containment at Sandia National Laboratories resulted in a failure mechanism in the liner that was not fully anticipated. Post-test analyses and experiments have been conducted to understand the failure better. This work and the activities that followed the test are reviewed. Areas in which additional research should be conducted are given. (orig.)

Evaluation of Joint Performance on High Nitrogen Stainless Steel Which is Expected to Have Higher Allergy Resistance

Science.gov (United States)

Nakano, Kouichi

Austenitic stainless steel, which includes nickel for stabilizing austenitic structure, is used for various purposes, for example, for structural material, corrosion-resistant material, biomaterial etc. Nickel is set as one of the rare metals and economizing on nickel as the natural resources is required. On the other hand, nickel is one of the metals that cause metallic allergy frequently. Therefore, high nitrogen stainless steel, where nitrogen stabilizes austenitic structure instead of nickel, has been developed in Japan and some of the foreign countries for the above reason. When high nitrogen stainless steel is fused and bonded, dissolved nitrogen is released to the atmospheric area, and some of the material properties will change. In this study, we bonded high nitrogen stainless steel by stud welding process, which is able to bond at short time, and we evaluate joint performance. We have got some interesting results from the other tests and examinations.

Rate of driving a ventilation tunnel by means of the GPK heading machine using roof bolting and steel supports. [USSR

Energy Technology Data Exchange (ETDEWEB)

Cheremnov, V.I.; Kruglyak, A.S.; Miroshnikova, L.A.; Sharov, V.N.

1983-05-01

The paper discusses a method for strata control during mine drivage tested in the im. Voroshilov coal mine in 1982. A ventilation tunnel with a crosscut of 16.4 m/sup 2/ was driven in coal with compression strength coefficient from 0.8 to 1.0, argillites and aleurites in the floor and the roof with compression strength coefficient from 4 to 6. Mining depth was 150 m, water influx was low. The tunnel was driven by means of the GPK heading machine with a 1PNB-2 loader. The AMK support system which consisted of arched steel supports, steel beams for joining steel arches and of roof bolts was used. Arched supports were installed each 0.8 m. The roof between the arches was supported by a system of roof bolts and junction beams. Support design is shown in a scheme. Increasing support spacing to 0.8 m (instead of 0.5 m) and roof bolting permitted drivage rate to be increased and steel consumption to be significantly reduced (by 244 kg/m). (3 refs.)

Mechanical properties of ASTM A508 Class 4 steel used in the LWBR closure head and support flange (LWBR Development Program)

International Nuclear Information System (INIS)

Allen, R.M.; Hall, J.F.

1978-07-01

The LWBR closure head and support flange are manufactured from forgings of ASTM A508 Class 4 steel rather than the ASTM A508 Class 2 forging material more commonly used in reactor vessels and closure heads. Forgings involved were approximately 300,000 pounds and 46,000 pounds. The extensive material test program conducted on ASTM A508 Class 4 LWBR forgings is described. The results of the tests confirm that the A508 Class 4 material used for the LWBR forgings has been quite good through thickness, fracture toughness, and strength properties and fully meet all specified requirements

Some considerations to the failure analysis of a pointwise attached steel liner membrane under constraint load

International Nuclear Information System (INIS)

Buchhardt, F.; Brandl, P.

1981-01-01

In the application of reinforced or prestressed concrete reactor containments, the safety enclosure will be obtained through a steel liner membrane, which is attached pointwise to the interior concrete surface. It is the objective and aim of this study to analyse the overall structural behaviour of the bonded system consisting of concrete containment, studs, and steel liner - especially under the aspect of extreme load and deformation conditions. The parametric analysis is carried out on the basis of the geometric length/depth ratio l/t = 12 of a single liner field. In order to reduce the considerable computational effort to a minimum, it is necessary to decouple the overall system in its structural components, i.e., at first an imperfect predeflected 'buckling' field and the residual 'plane' liner field are considered separately. A further reduction enables the use of stud anchor characteristics which are based on experiments. Three-dimensional analyses are performed for the single 'buckling' field to obtain specific load-displacement functions; the residual plane system is considered with two- as well as one-dimensional models. For the comprehensive parametric evalution of the overall system behaviour, a linear model is assumed to which these load-displacement functions are applied. Constraint temperatures are introduced as a unit scale - up to failure of the overall system; hereby partial structural failure might lead to temporary relief. (orig.)

Steel syndrome: dislocated hips and radial heads, carpal coalition, scoliosis, short stature, and characteristic facial features.

Science.gov (United States)

Flynn, John M; Ramirez, Norman; Betz, Randal; Mulcahey, Mary Jane; Pino, Franz; Herrera-Soto, Jose A; Carlo, Simon; Cornier, Alberto S

2010-01-01

A syndrome of children with short stature, bilateral hip dislocations, radial head dislocations, carpal coalitions, scoliosis, and cavus feet in Puerto Rican children, was reported by Steel et al in 1993. The syndrome was described as a unique entity with dismal results after conventional treatment of dislocated hips. The purpose of this study is to reevaluate this patient population with a longer follow-up and delineate the clinical and radiologic features, treatment outcomes, and the genetic characteristics. This is a retrospective cohort study of 32 patients in whom we evaluated the clinical, imaging data, and genetic characteristics. We compare the findings and quality of life in patients with this syndrome who have had attempts at reduction of the hips versus those who did not have the treatment. Congenital hip dislocations were present in 100% of the patients. There was no attempt at reduction in 39% (25/64) of the hips. In the remaining 61% (39/64), the hips were treated with a variety of modalities fraught with complications. Of those treated, 85% (33/39) remain dislocated, the rest of the hips continue subluxated with acetabular dysplasia and pain. The group of hips that were not treated reported fewer complaints and limitation in daily activities compared with the hips that had attempts at reduction. Steel syndrome is a distinct clinical entity characterized by short stature, bilateral hip and radial head dislocation, carpal coalition, scoliosis, cavus feet, and characteristic facial features with dismal results for attempts at reduction of the hips. Prognostic Study Level II.

Ultrasonic inspection of studs (bolts) using dynamic predictive deconvolution and wave shaping.

Science.gov (United States)

Suh, D M; Kim, W W; Chung, J G

1999-01-01

Bolt degradation has become a major issue in the nuclear industry since the 1980's. If small cracks in stud bolts are not detected early enough, they grow rapidly and cause catastrophic disasters. Their detection, despite its importance, is known to be a very difficult problem due to the complicated structures of the stud bolts. This paper presents a method of detecting and sizing a small crack in the root between two adjacent crests in threads. The key idea is from the fact that the mode-converted Rayleigh wave travels slowly down the face of the crack and turns from the intersection of the crack and the root of thread to the transducer. Thus, when a crack exists, a small delayed pulse due to the Rayleigh wave is detected between large regularly spaced pulses from the thread. The delay time is the same as the propagation delay time of the slow Rayleigh wave and is proportional to the site of the crack. To efficiently detect the slow Rayleigh wave, three methods based on digital signal processing are proposed: wave shaping, dynamic predictive deconvolution, and dynamic predictive deconvolution combined with wave shaping.

Lock-in thermographic inspection of squats on rail steel head

Science.gov (United States)

Peng, D.; Jones, R.

2013-03-01

The development of squat defects has become a major concern in numerous railway systems throughout the world. Infrared thermography is a relatively new non-destructive inspection technique used for a wide range of applications. However, it has not been used for rail squat detection. Lock-in thermography is a non-destructive inspection technique that utilizes an infrared camera to detect the thermal waves. A thermal image is produced, which displays the local thermal wave variation in phase or amplitude. In inhomogeneous materials, the amplitude and phase of the thermal wave carries information related to both the local thermal properties and the nature of the structure being inspected. By examining the infrared thermal signature of squat damage on the head of steel rails, it was possible to generate a relationship matching squat depth to thermal image phase angle, using appropriate experimental/numerical calibration. The results showed that with the additional data sets obtained from further experimental tests, the clarity of this relationship will be greatly improved to a level whereby infrared thermal contours can be directly translated into the precise subsurface behaviour of a squat.

INFLUENCE OF TEMPERATURE AND RELATIVE HUMIDITY ON THE STUDDED AGARICUS BLAZEI MURRILL MUSHROOM COMPOST

Directory of Open Access Journals (Sweden)

Sándor Rózsa

2017-12-01

Full Text Available Almond mushroom, Agaricus blazei Murrill, is the so-called secondary saprophyte, developing on partially processed substrate, in which microorganisms reduced complex ligno-cellulose compounds. Numerous authors have shown that due to the similar life cycle in the cultivation of almond mushroom technologies developed for white button mushroom may be applied. However, almond mushroom requires high temperature and high humidity as well as access to light to form fruiting bodies. In Brazil, due to the advantageous climatic conditions this species is frequently grown outdoors; however, in other countries - mainly due to its high temperature requirements - such cultivation system is risky and may only be successful during very warm summers. In this study, we analyzed four kind of compost studded by Agaricus blazei Murrill mushroom mycelium. We recorded every hour the air and compost temperature and the air relative humidity. The best studded compost was the classical, followed by synthetic and then by the mixt compost.

Anthelmintic efficacy on Parascaris equorum in foals on Swedish studs

Directory of Open Access Journals (Sweden)

Christensson Dan

2009-11-01

Full Text Available Abstract Background In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals. Methods A Faecal Egg Count Reduction Test (FECRT was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming and 14 days later. Faecal Egg Count Reductions (FECRs were calculated on arithmetic means of transformed individual FECRs and on arithmetic means of individual FECRs. Results Seventy-nine (48% out of a total of 165 foals sampled were positive for P. equorum eggs before deworming and 66 of these met the criteria for being used in the efficacy assessment. It was shown that there was no, or very low activity of ivermectin on the output of ascarid eggs in the majority of the foals, whereas for fenbendazole and pyrantel it was >90%. Conclusion Ivermectin resistance was shown in 5 out of 6 farms. Therefore, ivermectin should not be the drug of choice in the control of P. equorum infections in foals. According to the results of this study, fenbendazole or pyrantel are still effective and should be used against this parasite.

Mechanical splicing of superelastic Cu–Al–Mn alloy bars with headed ends

Science.gov (United States)

Kise, S.; Mohebbi, A.; Saiidi, M. S.; Omori, T.; Kainuma, R.; Shrestha, K. C.; Araki, Y.

2018-06-01

This paper examines the feasibility of mechanical splicing using a steel coupler to connect headed ends of superelastic Cu–Al–Mn alloy (Camalloy) bars and steel reinforcing bars to be used in concrete structures. Although threading of Camalloy is as easy as that of steel, mechanical splicing using threaded ends requires machining of Camalloy bars into dog-bone shape to avoid brittle fracture at the threaded ends. The machining process requires significant time and cost and wastes substantial amount of the material. This paper attempts to resolve this issue by applying mechanical splicing using steel couplers to connect headed ends of Camalloy and steel reinforcing bars. To study its feasibility, we prepare 3 specimens wherein both ends of each Camalloy bar (13 mm diameter and 300 mm length) are connected to steel reinforcing bars. The specimens are tested under monotonic, single-cycle, and full-cycle tension loading conditions. From these tests, we observed (1) excellent superelasticity with recoverable strain of around 6% and (2) large ductility with fracture strain of over 19%. It should be emphasized here that, in all the specimens, ductile fracture occurred at the locations apart from the headed ends. This is in sharp contrast with brittle fracture of headed superelastic Ni–Ti SMA bars, most of which took place around the headed ends. From the results of the microstructural analysis, we identified the following reasons for avoiding brittle fracture at the headed ends: (1) Precipitation hardening increases the strength around the boundary between the straight and headed (tapered) portions, where stress concentration takes place. (2) The strength of the straight portion does not increase significantly up to the ductile fracture if its grain orientation is close to 〈0 0 1〉.

Simulations of drastically reduced SBS with laser pulses composed of a Spike Train of Uneven Duration and Delay (STUD pulses)

International Nuclear Information System (INIS)

Hueller, S.; Afeyan, B.

2013-01-01

By comparing the impact of established laser smoothing techniques like Random Phase Plates (RPP) and Smoothing by Spectral Dispersion (SSD) to the concept of 'Spike Trains of Uneven Duration and Delay' (STUD pulses) on the amplification of parametric instabilities in laser-produced plasmas, we show with the help of numerical simulations, that STUD pulses can drastically reduce instability growth by orders of magnitude. The simulation results, obtained with the code Harmony in a nonuniformly flowing mm-size plasma for the Stimulated Brillouin Scattering (SBS) instability, show that the efficiency of the STUD pulse technique is due to the fact that successive re-amplification in space and time of parametrically excited plasma waves inside laser hot spots is minimized. An overall mean fluctuation level of ion acoustic waves at low amplitude is established because of the frequent change of the speckle pattern in successive spikes. This level stays orders of magnitude below the levels of ion acoustic waves excited in hot spots of RPP and SSD laser beams. (authors)

Development and anti-swing control of an automated measurement robot system for multi-stud tensioning machine

International Nuclear Information System (INIS)

Li Haoyuan; Li Meng; Duan Xingguang; Gao Liang; Cui Tengfei; Guo Yanjun

2017-01-01

During nuclear power plant maintenance, the multi-stud tensioning machine is used to perform opening/sealing the cap of the reactor pressure vessel. This process incorporates elongations of 58 studs, whose extension values are monitored in real time by measurement meters. Conventionally, the placements of the meters are performed by human labor, which is time consuming and radioactively hazardous. In this paper, we introduce an automated measurement robot system, consisting of 58 node robots and multiple field bus based distributed control devices, to complete meter placement and data acquisition tasks without human involvement in the hazardous working site. In order to eliminate the swing phenomenon of the wire-driven meter adaptor on the robot distal end, extra-insensitive input shaper is employed for robot motion control, thus saving the overall operation time from traditionally over 10 minutes to less than 22 s. (author)

Effects of commercial selenium products on glutathione peroxidase activity and semen quality in stud boars

Science.gov (United States)

The aim of this study was to determine how dietary supplementation of inorganic and organic selenium affects selenium concentration and glutathione peroxidase activity in blood and sperm of sexually mature stud boars. Twenty-four boars of the Large White, Landrace, Pietrain, and Duroc breeds of opt...

46 CFR 56.25-20 - Bolting.

Science.gov (United States)

2010-10-01

..., Blanks, Flange Facings, Gaskets, and Bolting § 56.25-20 Bolting. (a) General. (1) Bolts, studs, nuts, and....01-2). (2) Bolts and studs must extend completely through the nuts. (3) See § 58.30-15(c) of this... steel stud bolts must be threaded full length or, if desired, may have reduced shanks of a diameter not...

Detection of atypical porcine pestivirus in semen from commercial boar studs in the United States.

Science.gov (United States)

Gatto, I R H; Arruda, P H; Visek, C A; Victoria, J G; Patterson, A R; Krull, A C; Schwartz, K J; de Oliveira, L G; Arruda, B L

2018-04-01

Atypical porcine pestivirus (APPV) has recently been identified as a cause of congenital tremor (CT) in pigs and has been detected in semen and preputial swabs from boars that were known to be clinically affected with CT. Accordingly, the objectives of this study were to 1) detect the presence of APPV in semen, preputial fluids and preputial swabs from adult boars by quantitative reverse transcription PCR (qRT-PCR) and 2) genetically characterize a subset of positive samples to better understand the ecology of APPV in commercial boar studs and the potential risk of transmission of APPV via semen. A total of 597 samples of semen, preputial fluid and preputial swabs each representing a different boar were obtained from four commercial boar studs located in three different states in the United States. Viral RNA was detected by qRT-PCR in 90 samples (15.08%; 90/597), with the greatest per cent positive from preputial swabs (23.81%; 5/21) followed by preputial fluid (22.81%; 26/114) and semen (12.91%; 59/457). The mean cycle quantification (Cq) between sample types was similar while eleven semen samples had Cq values lower than 27.0 corresponding to approximately 2 × 10 6  copies/ml. Based on phylogenetic analysis of the Npro gene, different viral strains can be on the same farm at the same and different times. This is the first report of detection of APPV in semen from commercial boar studs. Studies investigating the role of semen in the transmission of APPV and production of CT are needed. © 2017 Blackwell Verlag GmbH.

Fire resistance of a steel plate reinforced concrete bearing wall

International Nuclear Information System (INIS)

Kodaira, Akio; Kanchi, Masaki; Fujinaka, Hideo; Akita, Shodo; Ozaki, Masahiko

2003-01-01

Samples from a steel plate reinforced concrete bearing wall composed of concrete slab sandwiched between studded steel plates, were subjected to loaded fire resistance tests. There were two types of specimens: some were 1800 mm high while the rest were 3000 mm high ; thickness and width were the same for all specimens, at 200 mm and 800 mm, respectively. Under constant load conditions, one side of each specimen was heated along the standard fire-temperature curve. The results enabled us to approximate the relationship between the ratio of working load to concrete strength N/(Ac x c σ b) and the fire resistance time (t: minutes), as equation (1) for the 1800 mm - high specimen, and equation (2) for the 3000 mm - high specimen. N/(Ac x c σ b) = 2.21 x (1/t) 0.323 (1), .N/(Ac x c σ b) 2.30 x (1/t) 0.378 (2) In addition, the temperature of the unheated side of the specimens was 100degC at 240 minutes of continuous heating, clearly indicating that there was sufficient heat insulation. (author)

Joining of hybrid AA6063-6SiCp-3Grp composite and AISI 1030 steel by friction welding

Directory of Open Access Journals (Sweden)

N. Rajesh Jesudoss Hynes

2017-10-01

Full Text Available Joining of metals and aluminium hybrid metal matrix composites has significant applications in aviation, ship building and automotive industries. In the present work, investigation is carried out on Friction Welding of AISI 1030 steel and hybrid AA6063-6SiCp-3Grpcomposite, that are difficult to weld by fusion welding technique. Silicon carbide and graphite particle reinforced AA6063 matrix hybrid composite was developed successfully using stir casting method and the joining feasibility of AISI1030 steel with AA6063-6SiCp-3Grp hybrid composite was tried out by friction stud welding technique. During friction stage of welding process, the particulates (SiC & Graphite used for reinforcement, tend to increase the viscosity and lead to improper mixing of matrix and reinforcement. This eventually results in lower strength in dissimilar joints. To overcome this difficulty AA1100 interlayer is used while joining hybrid composite to AISI 1030 steel. Experimentation was carried out using Taguchi based design of experiments (DOE technique. Multiple regression methods were applied to understand the relationship between process parameters of the friction stud welding process. Micro structural examination reveals three separate zones namely fully plasticized zone, partially deformed zone and unaffected base material zone. Ultra fine dynamically recrystallized grains of about 341 nm were observed at the fully plasticized zone. EDX analysis confirms the presence of intermetallic compound Fe2Al5 at the joint interface. According to the experimental analysis using DOE, rotational speed and interlayer sheet thickness contribute about 39% and 36% respectively in determining the impact strength of the welded joints. It is found that joining with 0.5 mm interlayer sheet provides efficient joints. Developed regression model could be used to predict the axial shortening distance and impact strength of the welded joint with reasonable accuracy.

Investigation on impact resistance of steel plate reinforced concrete barriers against aircraft impact. Pt.2: Simulation analysis of scale model impact tests

International Nuclear Information System (INIS)

Jun Mizuno; Norihide Koshika; Hiroshi Morikawa; Kentaro Wakimoto; Ryusuke Fukuda

2005-01-01

Steel plate reinforced concrete (SC) structure is one in which the rebars of conventional reinforced concrete (RC) structures are replaced with external steel plates attached to inner concrete with headed studs. SC structures are considered to be more effective than RC structures against aircraft impact, so their application to outer walls and roofs of risk-sensitive structures such as nuclear-related structures is expected to mitigate damage to critical components. The objective of this study was to investigate the fracture behavior and perforation thickness of SC panels against aircraft impact through impact tests and simulation analyses. Objectives of this paper are to analytically investigate the protection performance of SC panels against aircraft model impact through simulation analyses of 1/7.5 scale aircraft model impact tests presented in Part 1 of this study using a discrete element method (DEM), and to examine the applicability and validity of the DEM. Simulation analyses by a finite element method (FEM) were also performed to evaluate its applicability. The fracture process and damage to the SC test panels as well as the aircraft models are closely simulated by the discrete element analyses. The various impact responses and failure mechanisms, such as deceleration curves of projectile, velocity of debris from rear face and deformation mode of SC panels, are also simulated closely by the DEM analyses. The results of analyses confirm the shock-proof performance of SC panels against aircraft impact, and the applicability and validity of DEM for evaluating the complex phenomena of an aircraft impact against an SC panel. The finite element analysis closely simulates the deformation of the SC test panel and strains of rear steel plate where the global bending deformation mode is dominant. (authors)

49 CFR 178.506 - Standards for metal drums other than steel or aluminum.

Science.gov (United States)

2010-10-01

... aluminum. 178.506 Section 178.506 Transportation Other Regulations Relating to Transportation PIPELINE AND... drums other than steel or aluminum. (a) The following are the identification codes for metal drums other than steel or aluminum: (1) 1N1 for a non-removable head metal drum; and (2) 1N2 for a removable head...

An Induction Heating Method with Traveling Magnetic Field for Long Structure Metal

Science.gov (United States)

Sekine, Takamitsu; Tomita, Hideo; Obata, Shuji; Saito, Yukio

A novel dismantlable adhesion method for recycling operation of interior materials is proposed. This method is applied a high frequency induction heating and a thermoplastic adhesive. For an adhesion of interior material to long steel stud, a conventional spiral coil as like IH cooking heater gives inadequateness for uniform heating to the stud. Therefore, we have proposed an induction heating method with traveling magnetic field for perfect long structures bonding. In this paper, we describe on the new adhesion method using the 20kHz, three-phase 200V inverter and linear induction coil. From induction heating characteristics to thin steel plates and long studs, the method is cleared the usefulness for uniform heating to long structures.

Use of the cylindrically guided wave technique for the inspection of stud bolts, valve stems and pump shafts

International Nuclear Information System (INIS)

Light, G.M.; Bloom, E.A.; Ruescher, E.H.; Lui, S.N.

1989-01-01

Over the last several years, nuclear power plants have expressed concern about failures of bolting, valve stems, and pump shafts. This paper reports on the development of an ultrasonic technique to inspect these components. The authors have successfully demonstrated the cylindrically guided wave technique (CGWT) on a wide range of stud bolts. The CGWT employs zero-degree longitudinal waves constrained to travel within the boundary of the cylindrically shaped components during inspection. Theoretically explained, mode conversion occurs because the ultrasonic wave is guided down the length of the component. These mode-converted signals are dependent upon the diameter of the component under inspection and the longitudinal- and shear-wave velocities of the component material. This technique has also been successfully used on valve stems in the field. The geometry of the valve stem is very similar to that of the stud bolt

THE ANALYSIS OF REPRODUCTION INDICES IN THE TRANSYLVANIAN HALF-HEAVY HORSE BREED IN BECLEAN STUD FARM

Directory of Open Access Journals (Sweden)

IOANA CAMELIA LUDU

2007-10-01

Full Text Available The values of the main reproduction indices for the Transylvanian half-heavy horsematerial from Beclean stud farm are presented and analysed in this paper. Theanalysis is based on the data obtained from the evidence of the reproduction activityof 126 mother mares, data recorded in the period between 2000 and 2006. The mostsignificant indices have been rated, as the number of cycles/gestation, the number ofmatings/gestation, service-period (SP, gestation period (GP and the periodbetween bringing forth. The studied indices have been determined based on thenumber of bringing forth, on genealogical lines and on the entire population andaccording to the male stud used for mating. The connection between the puerperalperiod and the main reproduction indices has also been estimated. The averagevalues of the analysed reproduction indices show a normal evolution of thereproduction function for the Transylvanian half-heavy mother mares, a value that can behighlighted by creating some absolute accordance between the biological requests of thisbreed and the technological conditions which are provided for them.

BREEDING AND UTILIZATION OF ARABIAN HORSE TODAY

Directory of Open Access Journals (Sweden)

Vlasta Mandić

2000-06-01

Full Text Available Arab horse raising has a hundred year old tradition. A real stud farm raising started by purchasing original reproductive material from Asia in 1895, 1897 and 1899. Apart from state stud in Goražde, Arab horse was also raised in several private stud farms, especially in Slavonia and Srijem region. By the end of the II World war Arab horse raising was restricted to only 2-3 stud farms, regardless the above mentioned oldest Arab stud farm Goražde. According to reports refering to end of 1940 in former Yugoslavia there were slightly more than 150 grown up thoroughbred Arab heads, stallions and mares in both private and public property. A number of well known stud farms was reduced, thus, Arab horse raising was limited only to stud farms Goražde, Inocens Dvor and Karađorđevo. Sires were mostly used in Bosnian-mountain horse breeding whereas in plain areas they were used for ceossing with heavy draft mares or raising of, in that time numerous represented, nonius breed. The year 1970 was characterized by Arab horses reduction, thereby raising stagnation. Horse raising was closed, so, 77 Sabich stallion, bought in Germany, started again Arab horse raising, firstly in Goražde. It was also attributed by raising establishment of agricultural economy Višnjica near Slatina. At the same time Arab horse raising increased slowly at individual raisers in Kutina, Vrbovsko, Istria, Čađavica and Zagreb vicinity. According to available data from 1999 there were approx. 132 stallions and mares due to horse raisers scattered throught Croatia. All male and female reproductive heads were mostly used as raising heads for thoroughbred raising or for crossing with other breeds which is justified by the data from the period 1930-1935. On the other hand one part of reproductive heads, especially males, were used as sports heads for gallop races and distance riding as Arab horses were used by their arrival to present areas and by Arab horse raising tradition.

CORRELATION BETWEEN SOME BODY MEASURES OF LIPPIZANER STALLION PER LINES AT ĐAKOVO STUD

Directory of Open Access Journals (Sweden)

T. Rastija

2002-06-01

Full Text Available Body measures of Lippizaner line stallions and their correlation were processed in Đakovo stud. The measures performed by Lydtin rod and stock band included withers height, chest girth and cannon bone circumference on the total of 75 heads. Neapolitano line was characterized by the fewest number of stallions (4 whereas Tulip by the largest one (20. Data attained by the measuring were processed by the statistical program SPSS/PC (Nie et. al. 1975. Neapolitano line stallions had the lowest withers height (164.00 cm measured by the band whereas Conversano line stallions had the highest one (166.33 cm. Withers height measured by the rod was the lowest in the Maestoso line stallion (156.50 cm and the highest one in the Favory line (159.20 cm. Chest girth ranged between 183.82 cm (Pluto line and 186.89 cm (Conversano line. Cannon bone circumference was uniform with all lines ranged from 20.05 cm (Tulipan line and 20.65 cm (Maestoso lines. Correlation between withers height measured by the band and rod and that one measured by the rod and chest girth was positive and highly significant. However, correlation between others ranged from slight positive to slight negative. Neapolitano line was known for the most pronounced correlation per lines whereas Tulip line for the weakest one. Correlation between withers height measured by the band and rod was in all lines highly significant (except Tulip line whereas other correlation varied from positive to negative.

Apparatus and process for ultrasonic seam welding stainless steel foils

Science.gov (United States)

Leigh, Richard W.

1992-01-01

An ultrasonic seam welding apparatus having a head which is rotated to form contact, preferably rolling contact, between a metallurgically inert coated surface of the head and an outside foil of a plurality of layered foils or work materials. The head is vibrated at an ultrasonic frequency, preferably along a longitudinal axis of the head. The head is constructed to transmit vibration through a contacting surface of the head into each of the layered foils. The contacting surface of the head is preferably coated with aluminum oxide to prevent the head from becoming welded to layered stainless steel foils.

Integrity evaluation for stud female threads on pressure vessel according to ASME code using FEM

International Nuclear Information System (INIS)

Kim, Moon Young; Chung, Nam Yong

2003-01-01

The extension of design life among power plants is increasingly becoming a world-wide trend. Kori no.1 unit in Korea is operating two cycle. It has two man-ways for tube inspection in a steam generator which is one of the important components in a nuclear power plant. Especially, stud bolts for man-way cover have damaged by disassembly and assembly several times and degradation for bolt materials for long term operation. It should be evaluated and compared by ASME code criteria for integrity evaluation. Integrity evaluation criteria which has been made by the manufacturer is not applied on the stud bolts of nuclear pressure vessels directly because it is controlled by the yield stress of ASME code. It can apply evaluation criteria through FEM analysis to damaged female threads and to evaluated safety for helical-coil method which is used according to code case-N-496-1. From analysis results, we found that it is the same results between stress intensity which got from FEM analysis on damaged female threads over 10% by manufacture integrity criteria and 2/3 yield strength criteria on ASME code. It was also confirmed that the helical-coil repair method would be safe

Metallurgy of steels for PWR pressure vessels

International Nuclear Information System (INIS)

Kepka, M.; Mocek, J.; Barackova, L.

1980-01-01

A survey and the chemical compositions are presented of reactor pressure vessel steels. The metallurgy is described of steel making for pressure vessels in Japan and the USSR. Both acidic and alkaline open-hearth steel is used for the manufacture of ingots. The leading world manufacturers of forging ingots for pressure vessels, however, exclusively use electric steel. Vacuum casting techniques are exclusively used. Experience is shown gained with the introduction of the manufacture of forging ingots for pressure vessels at SKODA, Plzen. The metallurgical procedure was tested utilizing alkaline open hearths, electric arc furnaces and facilities for vacuum casting of steel. Pure charge raw materials should be used for securing high steel purity. Prior to forging pressure vessel rings, not only should sufficiently big bottoms and heads be removed but also the ingot middle part should be scrapped showing higher contents of impurities and nonhomogeneous structure. (B.S.)

Metallurgy of steels for PWR pressure vessels

Energy Technology Data Exchange (ETDEWEB)

Kepka, M; Mocek, J; Barackova, L [Skoda, Plzen (Czechoslovakia)

1980-09-01

A survey and the chemical compositions are presented of reactor pressure vessel steels. The metallurgy is described of steel making for pressure vessels in Japan and the USSR. Both acidic and alkaline open-hearth steel is used for the manufacture of ingots. The leading world manufacturers of forging ingots for pressure vessels, however, exclusively use electric steel. Vacuum casting techniques are exclusively used. Experience is shown gained with the introduction of the manufacture of forging ingots for pressure vessels at SKODA, Plzen. The metallurgical procedure was tested utilizing alkaline open hearths, electric arc furnaces and facilities for vacuum casting of steel. Pure charge raw materials should be used for securing high steel purity. Prior to forging pressure vessel rings, not only should sufficiently big bottoms and heads be removed but also the ingot middle part should be scrapped showing higher contents of impurities and nonhomogeneous structure.

Seismic Failure Mechanism of Reinforced Cold-Formed Steel Shear Wall System Based on Structural Vulnerability Analysis

Directory of Open Access Journals (Sweden)

Jihong Ye

2017-02-01

Full Text Available A series of structural vulnerability analyses are conducted on a reinforced cold-formed steel (RCFS shear wall system and a traditional cold-formed steel (CFS shear wall system subjected to earthquake hazard based on forms in order to investigate their failure mechanisms. The RCFS shear wall adopts rigid beam-column joints and continuous concrete-filled CFS tube end studs rather than coupled-C section end studs that are used in traditional CFS shear walls, to achieve the rigid connections in both beam-column joints and column bases. The results show that: the RCFS and traditional CFS shear wall systems both exhibit the maximum vulnerability index associated with the failure mode in the first story. Therefore, the first story is likely to be a weakness of the CFS shear wall system. Once the wall is damaged, the traditional CFS shear wall system would collapse because the shear wall is the only lateral-resisting component. However, the collapse resistance of the RCFS shear wall system is effectively enhanced by the second defense, which is provided by a framework integrated by rigid beam-column joints and fixed column bases. The predicted collapse mode with maximum vulnerability index that was obtained by structural vulnerability analysis agrees well with the experimental result, and the structural vulnerability method is thereby verified to be reasonable to identify the weaknesses of framed structures and predict their collapse modes. Additionally, the quantitative vulnerability index indicates that the RCFS shear wall system exhibits better robustness compared to the traditional one. Furthermore, the “strong frame weak wallboard” and the “strong column weak beam” are proposed in this study as conceptional designations for the RCFS shear wall systems.

Development of SC structure modularization in Nuclear Power Plant

International Nuclear Information System (INIS)

Mun, Taeyoup

2008-01-01

New Focus on NPP are Rising Concerns on Global Warming, Potential energy crisis (geo-political), Improved reliability and safety of nuclear power plant, Advent of Generation 3+ NPP technology and Economical Energy Resource. New NPPs are 6 units in Korea and 23 in Asia being built, 32 units being planned in China by 2020 (150 by 2050), 10 units being planned in US by 2020 and IAEA expects $200 billions on NPP construction next 25 years (up to 30% of total world energy). □ SC(Steel Plate Concrete) structure · Steel Plate is used as a Structural Element instead of Reinforcing Bars in RC · SC structure consists of Steel Plate with Headed Studs. Connected by Tie-bars - The Primary Purpose of Tie-bars is to Stiffen and Hold Together the Plates during Construction Process - Headed Studs are Welded to the Inside of Steel Plate for composite action □ Benefits of SC Structure · Shorten Construction Duration for Re bar, Forming and Scaffolding Works · Minimize Site Labors · Improve the Construction Quality · Enable Construction Sites to be kept Clean □ SC Modularization · Fit for Modular Construction for Structural Features · Fit for Modular Construction for Structural Features · Inattentively Effective for Integrated Modules · Pre-fabrication, Pre-assembly and Modularization □ Project Overview · Project Name: Development of SC structure for Modularization in NPP · Project Type: Electric Power Industry R and D (Ministry of Knowledge Economy) · Duration: Sep. 2005 ∼ Aug. 2008 (36 Months) · Research Team and Scopes - Project Management: Korea Hydro and Nuclear Power Company (KHNP) - Development of Code and Standards for SC Structure: Korea Society of Steel Construction (KSSC) Korea Electric Power Research Institute (KEPRI) - Development of SC Structural Analysis and Design: Korea Power Engineering Company (KOPEC) - Development of Construction Techniques for SC Modularization: KHNP, Korea Institute of Nuclear Safety(KINS), KOPEC □ Performance

Computational fluid dynamic analysis of a closure head penetration in a pressurized water reactor

Energy Technology Data Exchange (ETDEWEB)

Forsyth, D.R.; Schwirian, R.E. [Westinghouse Electric Corp., Pittsburgh, PA (United States)

1995-09-01

ALLOY 600 has been used typically for penetrations through the closure head in pressurized water reactors because of its thermal compatibility with carbon steel, superior resistance to chloride attack and higher strength than the austenitic stainless steels. Recent plant operating experience with this alloy has indicated that this material may be susceptible to degradation. One of the major parameters relating to degradation of the head penetrations are the operational temperatures and stress levels in the penetration.

A compression and shear loading test of concrete filled steel bearing wall

International Nuclear Information System (INIS)

Akiyama, Hiroshi; Sekimoto, Hisashi; Fukihara, Masaaki; Nakanishi, Kazuo; Hara, Kiyoshi.

1991-01-01

Concrete-filled steel bearing walls called SC structure which are the composite structure of concrete and steel plates have larger load-carrying capacity and higher ductility as compared with conventional RC structures, and their construction method enables the rationalization of construction procedures at sites and the shortening of construction period. Accordingly, the SC structures have become to be applied to the inner concrete structures of PWR nuclear power plants, and subsequently, it is planned to apply them to the auxiliary buildings of nuclear power plants. The purpose of this study is to establish a rational design method for the SC structures which can be applied to the auxiliary buildings of nuclear power plants. In this study, the buckling strength of surface plates and the ultimate strength of the SC structure were evaluated with the results of the compression and shear tests which have been carried out. The outline of the study and the tests, the results of the compression test and the shear test and their evaluation are reported. Stud bolts were effective for preventing the buckling of surface plates. The occurrence of buckling can be predicted analytically. (K.I.)

77 FR 14445 - Application for a License To Export Steel Forging

Science.gov (United States)

2012-03-09

... NUCLEAR REGULATORY COMMISSION Application for a License To Export Steel Forging Pursuant to 10 CFR 110.70(b) ``Public Notice of Receipt of an Application,'' please take notice that the Nuclear... head steel February 7, 2012 forging. forging will be XR175 machined into the 11005983 finished vessel...

Experimental, numerical, and analytical studies on the seismic response of steel-plate concrete (SC) composite shear walls

Science.gov (United States)

Epackachi, Siamak

The seismic performance of rectangular steel-plate concrete (SC) composite shear walls is assessed for application to buildings and mission-critical infrastructure. The SC walls considered in this study were composed of two steel faceplates and infill concrete. The steel faceplates were connected together and to the infill concrete using tie rods and headed studs, respectively. The research focused on the in-plane behavior of flexure- and flexure-shear-critical SC walls. An experimental program was executed in the NEES laboratory at the University at Buffalo and was followed by numerical and analytical studies. In the experimental program, four large-size specimens were tested under displacement-controlled cyclic loading. The design variables considered in the testing program included wall thickness, reinforcement ratio, and slenderness ratio. The aspect ratio (height-to-length) of the four walls was 1.0. Each SC wall was installed on top of a re-usable foundation block. A bolted baseplate to RC foundation connection was used for all four walls. The walls were identified to be flexure- and flexure-shear critical. The progression of damage in the four walls was identical, namely, cracking and crushing of the infill concrete at the toes of the walls, outward buckling and yielding of the steel faceplates near the base of the wall, and tearing of the faceplates at their junctions with the baseplate. A robust finite element model was developed in LS-DYNA for nonlinear cyclic analysis of the flexure- and flexure-shear-critical SC walls. The DYNA model was validated using the results of the cyclic tests of the four SC walls. The validated and benchmarked models were then used to conduct a parametric study, which investigated the effects of wall aspect ratio, reinforcement ratio, wall thickness, and uniaxial concrete compressive strength on the in-plane response of SC walls. Simplified analytical models, suitable for preliminary analysis and design of SC walls, were

Structural design of nuclear power plant using stiffened steel plate concrete structure

International Nuclear Information System (INIS)

Moon, Ilhwan; Kim, Sungmin; Mun, Taeyoup; Kim, Keunkyeong; Sun, Wonsang

2009-01-01

Nuclear power is an alternative energy source that is conducive to mitigate the environmental strains. The countries having nuclear power plants are encouraging research and development sector to find ways to construct safer and more economically feasible nuclear power plants. Modularization using Steel Plate Concrete(SC) structure has been proposed as a solution to these efforts. A study of structural modules using SC structure has been performed for shortening of construction period and enhancement of structural safety of NPP structures in Korea. As a result of the research, the design code and design techniques based on limit state design method has been developed. The design code has been developed through various structural tests and theoretical studies, and it has been modified by application design of SC structure for NPP buildings. The code consists of unstiffened SC wall design, stiffened SC wall design, Half-SC slab design, stud design, connection design and so on. The stiffened steel plate concrete(SSC) wall is SC structure whose steel plates with ribs are composed on both sides of the concrete wall, and this structure was developed for improved constructability and safety of SC structure. This paper explains a design application of SC structure for a sample building specially devised to reflect all of major structural properties of main buildings of APR1400. In addition, Stiffening effect of SSC structure is evaluated and structural efficiency of SSC structure is verified in comparison with that of unstiffened SC structure. (author)

High-speed fiber laser cutting of thick stainless steel for dismantling tasks

Science.gov (United States)

Shin, Jae Sung; Oh, Seong Yong; Park, Hyunmin; Chung, Chin-Man; Seon, Sangwoo; Kim, Taek-Soo; Lee, Lim; Choi, Byung-Seon; Moon, Jei-Kwon

2017-09-01

A high-speed fiber laser cutting technology of thick steels for dismantling tasks was achieved using a 6-kW fiber laser system. At first, a new cutting head for efficient cutting of thick steels was developed, which was composed by a collimator with a focal length of 160 mm and mirror-type focusing objects with a long focal length of 600 mm. The long focal length of the focusing object made it possible for the beam size to be small through the thick cutting material and the cutting efficiency was expected to increase compared with the short focal length. In addition, folding the beam facilitated the compact cutting head with a size of 160 mm (width) × 80 mm (height) × 640 mm (length) and a weight of 6.9 kg. In the cutting experiment, the laser beam was delivered to the cutting head by a 25-m long process fiber with a core diameter of 100 μm. The cutting performances were studied against the thicknesses of stainless steel plates. A maximum cutting speed of 72 mm/min was obtained for the 60-mm thick stainless steel plate cutting and the cut specimen showed an excellent kerf shape and a narrow kerf width. To the best of our knowledge, this cutting speed was higher than other previously reported results when cutting with a 6-kW laser power.

Experimental tests on buckling of ellipsoidal vessel heads under internal pressure

International Nuclear Information System (INIS)

Alix, Michel; Roche, Roland.

1979-01-01

Seventeen heads made out of metal sheets -by cold working- were tested. Three different metals were used - carbon steel, austenitic steel, and aluminium alloy. Nominal dimensions were: diameter D 500 mm height H 50 and 100 mm thickness to diameter ratio t/D in the range 0.001-0.005. The heads had a good axisymmetric shape, but that the thickness was varying along the ellipse. Material characteristic of each head was given by a tensile test (strain-stress curve). The obtained results are mainly the pressure deflexion recordings, strain measurements and visual observations of the geometrical changes. For thin heads, buckling is a very fast event and the first folding occurs sudently, with a strong perturbation on the pressure-deflexion curve. For the thickest heads, circular waves are slowly forming. In all of these tests, yielding occured before buckling and it was possible to increase the pressure beyond the first buckling pressure without failure. The experimental results agree very well (+-5% except one head) with the empirical formula Psub(c)=70000.(sigma y+sigma u/2)(t/D)sup(5/3)((D/H) 2 -8)sup(-2/3). The following notations being used: Psub(c): critical buckling pressure; sigma y: yield strength; sigma u: ultimate stress (same unit); t: knuckle thickness; D: mean diameter; H: height (same unit) [fr

MAAP4 hot leg and lower head failure benchmarking

International Nuclear Information System (INIS)

Lee, S.J.; Henry, R.E.; Paik, C.Y.; Conzen, J.; Luangdilok, W.

2009-01-01

The MAAP4 material creep calculation was compared with the experiments reported by Maile, et al., for a 0.7 m diameter hot leg, with a thickness of 47 mm, which is pressurized to 16.3 MPa and heated to temperatures in excess of 700degC. These experiments showed that the carbon steel hot leg would undergo material creep to a failure state in approximately 1,100 seconds. In addition, the MAAP4 creep calculation was compared with the lower head failure tests performed at the Sandia National Laboratories (SNL). These experiments were performed using scaled models of a typical Reactor Pressure Vessel lower head. The test vessel was fabricated from SA533B1 steel with an inner diameter of 0.91 m and a nominal thickness of 30 mm. The experiments were performed at around 10 MPa internal pressure with various imposed heat flux distributions. The onset of creep was observed to occur between 660degC and 705degC. The MAAP4 model provides a good characterization of the material creep behavior. For the hot leg test benchmark, the key is determining the correct equivalent stress when the stress is multi-axial. A good agreement was obtained when a multiplier of 1.09 to the hoop stress was used. For the lower head failure benchmark, using correct creep properties is important. The SNL test vessel material was fabricated as SA533B1 steel. However, when the experimental vessel material was tested for creep properties it turned out to be significantly weaker than the reactor vessel steel which has the same identification. Also, the material undergoing phase transition and becoming stronger at high temperatures has to be considered for accurate prediction of the failure time. A good agreement was obtained when the creep data of Jeong, et al., was used. (author)

Buckling calculations with the CEASEMT system for elliptical heads subjected to an internal pressure. Comparison with the Saclay experiments

International Nuclear Information System (INIS)

Bung, Hariddh; Alix, Michel; Hoffmann, Alain.

1980-06-01

In this paper, Buckling calculations with the CEASEMT System (INCA) are compared with experimental results obtained on elliptical heads subjected to an internal pressure. Tests were performed with 18 ellipsoidal heads welded on cylinders made of carbon steel A 36-401, stainless steel Z6CN18-09 and aluminium-magnesium alloys (AG3). Experimental data are higher than calculated data, this leads to a good safety factor [fr

Adhesion, friction and wear between polytetrafluoroethylene and nitrogen-implanted stainless steel

International Nuclear Information System (INIS)

Yang, E.; Hirvonen, J.P.; Raesaenen, M.; Toivanen, R.O.

1992-01-01

Adhesion, friction and wear of polytetrafluoroethylene (PTFE), carbon-reinforced PTFE, and glass-reinforced PTFE in sliding contact with nitrogen-implanted and unimplanted AISI 316 stainless steel were determined. The transfer of PTFE within the first 10 unidirectional traverses was investigated using the 19 F(p,αγ) 16 O nuclear reaction. External proton beam induced X-ray emission (PIXE) was used to determine the metal transfer from AISI 316 to pin heads. Nitrogen implantation considerably reduced the transfer of PTFE to the steel surface, and the transfer of the metallic elements from stainless steel to the PTFE-based composites. Furthermore, a lower friction coefficient was observed for nitrogen-implanted samples within the first 400 revolutions. The wear of PTFE, glass-reinforced and carbon-reinforced PTFE pins was only slightly reduced on the nitrogen-implanted surface, although a significant improvement in the wear of the steel was observed. Transmission electron microscopy (TEM) examination of wear debris revealed that PTFE was amorphized during the transfer process. However, no change in the structure of the pin head prior to the transfer was detected with an IR spectrophotometer. (orig.)

Effects of Head Size on the Performance of Twist-Off Bolts

OpenAIRE

Schnupp, Keith Otto

2003-01-01

This study examines a specific application of button-head type twist-off bolts. Currently, the Research Council on Structural Connections Specification (2000) removes the requirement for ASTM F436 washers (ASTM 2000a) under the bolt head of twist-off bolts where the head diameter equals or exceeds that of an ASTM F436 washer when oversized and slotted holes are used. The need for washers is also removed for A490 strength bolts used on steels with specified yield strengths less than 40 ksi p...

Operational monitoring of temperature and state of stress of primary collectors, their stud bolts and cover and temperatures of steam generator's pressure vessel at the nuclear power unit WWER 440

International Nuclear Information System (INIS)

Matal, O.; Simo, T.; Holy, F.; Vejvoda, S.

1992-01-01

Both primary collectors of the WWER 440 steam generator (STGE) are vertically positioned inside the STGE pressure vessel and connected in their lower part to the primary piping and closed at their upper part by primary covers. The primary cover is pushed against the primary collector flange by 20 stud bolts. Two nickel packing rings are fitted between the primary cover and collector. A leakage in the collector-cover junction could cause flow of the radioactive water into the clean secondary water. If the junction is made in accordance with the Soviet standard design the computed stresses exceed the allowable value in the stud bolts by a factor of 1.5. Therefore an improved design of the primary collector - primary cover flange joint was designed and tested on one STGE at a WWER 440 nuclear power unit in Czechoslovakia. The paper describes the system of joint properties measurement, gives some substantial characteristics of the new stud bolts and primary cover design and comments on significant measured results of state of stress and temperatures in comparison with the operational regime of the STGE. (orig.)

76 FR 75871 - Certain Steel Nails From the People's Republic of China: Final Rescission of Antidumping Duty New...

Science.gov (United States)

2011-12-05

... order includes certain steel nails having a shaft length up to 12 inches. Certain steel nails include... any type of steel, and have a variety of finishes, heads, shanks, point types, shaft lengths and shaft... collated with adhesive or polyester film tape backed with a heat seal adhesive. Also excluded from the...

Steel containment buckling

International Nuclear Information System (INIS)

Bennett, J.G.; Fly, G.W.; Baker, W.E.

1984-01-01

The Steel Containment Buckling program is in its fourth phase of work directed at the evaluation of the effects of the structural failure mode of steel containments when the membrane stresses are compressive. The structural failure mode for this state of stress is instability or buckling. The program to date has investigated: (1) the effect on overall buckling capacity of the ASME area replacement method for reinforcing around circular penetrations; (2) a set of benchmark experiments on ring-stiffened shells having reinforced and framed penetrations; (3) large and small scale experiments on knuckle region buckling from internal pressure and post-buckling behavior to failure for vessel heads having torispherical geometries; and (4) buckling under time-dependent loadings (dynamic buckling). The first two investigations are complete, the knuckle buckling experimental efforts are complete with data analysis and reporting in progress, and the dynamic buckling experimental and analytical work is in progress

Reactor thread-joint metal with corrosion resistant coating material low cycle fatigue

International Nuclear Information System (INIS)

Gorynin, V.I.; Kondratyev, S.Yu.

1991-01-01

The results of test carried out show that the Ni-P plating which was thermally treated in inert medium, provide the dependence of the reactor equipment studs in the high-concentrated medium of leakage for a period of up to 3000 hours. The Al and aluminized platings of the studs made of steel 38 KhN 3 MFA don't provide their corrosion dependence in the reactor medium. Cr plating provides the dependence during 500 hours. The reported test allows to recommend Ni-P plating to depend the studs in the conditions of the effect of the high-concentrated leakage medium, containing KOH, H 3 BO 3 and NaCl. (author)

Sustainable RC Beam-Column Connections with Headed Bars: A Formula for Shear Strength Evaluation

Directory of Open Access Journals (Sweden)

Minh-Tung Tran

2018-02-01

Full Text Available Beam-column joints are critical regions for reinforced concrete (RC frames subjected to earthquakes. The steel reinforcement is, in general, highly concentrated in these zones. This is why in many cases, headed bars are used. A headed bar is a longitudinal steel reinforcement whose end has a special button added to reduce the bonding length of the steel rebar. This paper establishes a formula predicting the shear strength of exterior RC beam-column connections where the beam longitudinal reinforcements use headed bars. A database was collected, which contained 30 experimental data about the exterior beam-column joints using headed bars and subjected to quasi-static cyclic loading. First, from the collected database, a statistical study was carried out to identify the most influencing parameters on the shear strength of the beam-column joints tested. The three most important parameters were identified and an empirical modified formula was developed based on the formula existing in the standards. The study showed that the results obtained from the modified formula proposed in the present study were closer to the experimental results than that obtained from the formula existing in the standards. Finally, a numerical study was performed on two T-form RC structures and the numerical results were compared with the prediction calculated from the modified formula proposed. For two investigated cases, the proposed formula provided the results in the safety side and the differences with the numerical results were less than 20%. Thus, the proposed formula can be used for a rapid assessment of the shear strength of RC joints using headed bars.

Aircraft-crash-protected steel reactor building roof structure for the European market

International Nuclear Information System (INIS)

Posta, B.A.; Kadar, I.; Rao, A.S.

1996-01-01

This paper recommends the use of all steel roof structures for the reactor building of European Boiling Water Reactor (BWR) plants. This change would make the advanced US BWR designs more compatible with European requirements. Replacement of the existing concrete roof slab with a sufficiently thick steel plate would eliminate the concrete spelling resulting from a postulated aircraft crash, potentially damaging the drywell head or the spent fuel pool

Correction of the calculation of the ultimate strength of studs shear connectors in solid slab composite section; Correccion del calculo de la capacidad resistente ultima de conectadores tipo perno de estructuras mixtas en la tipologia de viga-losa maciza

Energy Technology Data Exchange (ETDEWEB)

Bonilla Rocha, J. D.; Larrua Quevedo, R.; Recarey Morfa, C. A.; Mirambell Arrizabalaga, E.

2009-07-01

In this work is studied starting from the numeric simulation with previous calibration and validation, the behavior of studs shear connectors of composite structures of concrete and steel formed by beam sections and solid slab of concrete, subjected to flexion under loads static. In such a sense it is carried out a parametric study that allows to value the influence of the different factors that intervene in the behavior of the connection and allow to establish the variables of the proposed formulation, obtaining a procedure enough easy and practical. Finally a new formulation the one is achieved which supposes a significant advances with regard to the existent ones in the main ones normative international: AISC-LRFD (2005), Eurocode 4 (IN-1994-1-1:2004), as well as the normative cuban NR 080-2004, when taking in consideration in the expression new factors, redounding in a bigger in the presage of the ultimate strength capacity. (Author) 22 refs.

Influence of slab connection in case of expanded concrete pavements

OpenAIRE

Deluka-Tibljaš, Aleksandra; Prager, Andrija; Rukavina, Tatjana

2002-01-01

Load transfer from the stressed slab to the neighboring unstressed slab is analyzed in order to establish possibilities for stress reduction in concrete. The contact between slabs is established by means of reinforcing steel shear studs while the influence of friction in the concrete to concrete contact is neglected. The influence of slab thickness, slab cross-section and spacing of shear studs is analyzed, and the expansion joint movement due to change in temperature is studied. Conditions e...

Containment liner plate anchors and steel embedments test results

International Nuclear Information System (INIS)

Chang-Lo, P.L.; Johnson, T.E.; Pfeifer, B.W.

1977-01-01

This paper summarizes test data on shear load and deformation capabilities for liner plate line anchors and structural steel embedments in reinforced and prestressed concrete nuclear containments. Reinforced and prestressed nuclear containments designed and constructed in the United States are lined with a minimum of 0.64 cm steel plate. The liner plates are anchored by the use of either studs or structural members (line anchors) which usually run in the vertical direction. This paper will only address line anchors. Static load versus displacement test data is necessary to assure that the design is adequate for the maximum loads. The test program for the liner anchors had the following major objectives: determine load versus displacement data for a variety of anchors considering structural tees and small beams with different weld configurations, from the preceding tests, determine which anchors would lead to an economical and extremely safe design and test these anchors for cyclic loads resulting from thermal fluctuations. Various concrete embeds in the containment and other structures are subjected to loads such as pipe rupture which results in shear. Since many of the loads are transient by nature, it is necessary to know the load-displacement relationship so that the energy absorption can be determined. The test program for the embeds had the following objectives: determine load-displacement relationship for various size anchors from 6.5 cm 2 to 26 cm 2 with maximum capacities of approximately 650 kN; determine the effect of various anchor width-to-thickness ratios for the same shear area

Ensayo no destructivo de soldaduras en pernos conectores mediante inspección acústica

Directory of Open Access Journals (Sweden)

Aznar, A.

2012-09-01

Full Text Available Headed studs are nowadays the standard steel-concrete connectors because of their competitive advantages. Firstly, they provide a high degree of safety thanks to semiautomatic electric arc welding. These welds are not suitable for typical non-destructive tests. The analytical study comprises several models. The first vibration modes have been obtained. The experimental research has developed first the measurement of the natural frequencies of 28 headed-studs in the sonic range. Then they have been tested by non-destructive and destructive tests. Finally theirs tests have been compared with their respective frequency measurements. A clear relationship between the measured frequencies and the lack of penetration of the welds has been established, that confirms the analytical prediction of this effect of the internal weld imperfections. Therefore, the feasibility of simple and absolutely non-destructive tests of welded studs by in site measurement of natural frequencies in the sonic range has been clearly established in this work.

Los pernos conectores aportan múltiples ventajas de uso, entre las que se encuentra el elevado margen de seguridad que ofrecen sus soldaduras ejecutadas mediante arco eléctrico. Estas soldaduras, aunque ampliamente fiables, son difícilmente comprobadas mediante ensayos no destructivos. El presente estudio plantea la inspección de soldaduras de pernos conectores mediante su espectro acústico. Analíticamente, la investigación se ha centrado en el cálculo de los primeros modos propios de vibración. Experimentalmente se han medido las frecuencias propias de resonancia de 28 pernos, en los que posteriormente se han llevado a cabo ensayos tanto no destructivos como destructivos. Se ha obtenido, tanto teórica como experimentalmente, una relación entre la frecuencia de vibración de los pernos conectores y la calidad de la soldadura. Por ello se verifica la posibilidad de inspección de estas

A preliminary study on the local impact behavior of Steel-plate Concrete walls

International Nuclear Information System (INIS)

Kim, Kap-sun; Moon, Il-hwan; Choi, Hyung-jin; Nam, Deok-woo

2017-01-01

International regulations for nuclear power plants strictly prescribe the design requirements for local impact loads, such as aircraft engine impact, and internal and external missile impact. However, the local impact characteristics of Steel-plate Concrete (SC) walls are not easy to evaluate precisely because the dynamic impact behavior of SC walls which include external steel plate, internal concrete, tie-bars, and studs, is so complex. In this study, dynamic impact characteristics of SC walls subjected to local missile impact load are investigated via actual high-speed impact test and numerical simulation. Three velocity checkout tests and four SC wall tests were performed at the Energetic Materials Research and Testing Center (EMRTC) site in the USA. Initial and residual velocity of the missile, strain and acceleration of the back plate, local failure mode (penetration, bulging, splitting and perforation) and deformation size, etc. were measured to study the local behavior of the specimen using high speed cameras and various other instrumentation devices. In addition, a more advanced and applicable numerical simulation method using the finite element (FE) method is proposed and verified by the experimental results. Finally, the experimental results are compared with the local failure evaluation formula for SC walls recently proposed, and future research directions for the development of a refined design method for SC walls are reviewed.

Influence of modern studded and bladed soccer boots and sidestep cutting on knee loading during match play conditions.

Science.gov (United States)

Kaila, Rajiv

2007-09-01

The influence of modern studded and bladed soccer boots and sidestep cutting on noncontact knee loading during match play conditions is not fully understood. Modern soccer boot type and sidestep cutting compared with straight-ahead running do not significantly influence knee internal tibia axial and valgus moments, anterior joint forces, and flexion angles. Controlled laboratory study. Fifteen professional male outfield soccer players undertook trials of straight-ahead running and sidestep cutting at 30 degrees and 60 degrees with a controlled approach velocity on a Fédération Internationale de Football Association (FIFA) approved soccer surface. Two bladed and 2 studded soccer boots from 2 manufacturers were investigated. Three-dimensional inverse dynamics analysis determined externally applied internal/external tibia axial and valgus/varus moments, anterior forces, and flexion angles throughout stance. The soccer boot type imparted no significant difference on knee loading for each maneuver. Internal tibia and valgus moments were significantly greater for sidestep cutting at 30 degrees and 60 degrees compared with straight-ahead running. Sidestep cutting at 60 degrees compared with straight-ahead running significantly increased anterior joint forces. Varying soccer boot type had no effect on knee loading for each maneuver, but sidestep cutting significantly increased internal tibia and valgus moments and anterior joint forces. Sidestep cutting, irrespective of the modern soccer boot type worn, may be implicated in the high incidence of noncontact soccer anterior cruciate ligament injuries by significantly altering knee loading.

Structural behavior of lightweight bamboo reinforced concrete slab with EPS infill panel

Science.gov (United States)

Wibowo, Ari; Wijatmiko, Indradi; Nainggolan, Christin Remayanti

2017-09-01

Eco-friendly, green, and natural materials have become increasingly important issues in supporting sustainable development, for the substitution of nonrenewable materials such as steel. Bamboo has been considered in many studies to replace steel in reinforced concrete elements. Further investigation has been carried out to obtain lightweight and eco-friendly reinforced concrete slabs by using bamboo bars as reinforcement and recycled materials such as EPS (expanded polystyrene) as infill panel. The flexural loading test on full scale one-way slabs test has been conducted. The results showed that the flexural strength of specimens decreased marginally of about 6% but with the weight advantage of 27% less compared with those of steel rebar reinforced concrete slab with the same dimension. Two type shear-connectors comprising of concrete and bamboo studs were also investigated which showed that the bamboo stud provided better ductility compared to that of slab with concrete as shear connector. Overall, the reinforced concrete slab with bamboo reinforcement and EPS infill panel showed reasonably good performance compared to slabs with steel rebar.

Thermal and stress analyses of the reactor pressure vessel lower head of the Three Mile Island Unit 2

International Nuclear Information System (INIS)

Hashimoto, K.; Onizawa, K.; Kurihara, R.; Kawasaki, S.; Soda, K.

1992-01-01

Thermal and stress analyses were performed using the finite element analysis code ABAQUS to clarify the factors which caused tears in the stainless steel liner of the reactor pressure vessel lower head of the Three Mile Island Unit 2 (TMI-2) reactor pressure vessel during the accident on 28 March 1979. The present analyses covered the events which occurred after approximately 20 tons of molten core material were relocated to the lower head of the reactor pressure vessel. They showed that the tensile stress was highest in the case where the relocated core material consisting of homogeneous UO 2 debris was assumed to attack the lower head and the debris was then quenched. The peak tensile stress was in the vicinity of the welded zone of the penetration nozzle. This result agrees with the findings from the examination of the TMI-2 reactor pressure vessel that major tears in the stainless steel liner were observed around two penetration nozzles of the lower head. (author)

Development of SC structure modularization in Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Mun, Taeyoup [Korea Hydro and Nuclear Power Co., Ltd., Seoul (Korea, Republic of)

2008-04-15

New Focus on NPP are Rising Concerns on Global Warming, Potential energy crisis (geo-political), Improved reliability and safety of nuclear power plant, Advent of Generation 3+ NPP technology and Economical Energy Resource. New NPPs are 6 units in Korea and 23 in Asia being built, 32 units being planned in China by 2020 (150 by 2050), 10 units being planned in US by 2020 and IAEA expects $200 billions on NPP construction next 25 years (up to 30% of total world energy). {open_square} SC(Steel Plate Concrete) structure {center_dot} Steel Plate is used as a Structural Element instead of Reinforcing Bars in RC {center_dot} SC structure consists of Steel Plate with Headed Studs. Connected by Tie-bars - The Primary Purpose of Tie-bars is to Stiffen and Hold Together the Plates during Construction Process - Headed Studs are Welded to the Inside of Steel Plate for composite action {open_square} Benefits of SC Structure {center_dot} Shorten Construction Duration for Re bar, Forming and Scaffolding Works {center_dot} Minimize Site Labors {center_dot} Improve the Construction Quality {center_dot} Enable Construction Sites to be kept Clean {open_square} SC Modularization {center_dot} Fit for Modular Construction for Structural Features {center_dot} Fit for Modular Construction for Structural Features {center_dot} Inattentively Effective for Integrated Modules {center_dot} Pre-fabrication, Pre-assembly and Modularization {open_square} Project Overview {center_dot} Project Name: Development of SC structure for Modularization in NPP {center_dot} Project Type: Electric Power Industry R and D (Ministry of Knowledge Economy) {center_dot} Duration: Sep. 2005 {approx} Aug. 2008 (36 Months) {center_dot} Research Team and Scopes - Project Management: Korea Hydro and Nuclear Power Company (KHNP) - Development of Code and Standards for SC Structure: Korea Society of Steel Construction (KSSC) Korea Electric Power Research Institute (KEPRI) - Development of SC Structural Analysis and Design

STRENGTHENING OF A REINFORCED CONCRETE BRIDGE WITH PRESTRESSED STEEL WIRE ROPES

Directory of Open Access Journals (Sweden)

Kexin Zhang

2017-10-01

Full Text Available This paper describes prestressed steel wire ropes as a way to strengthen a 20-year-old RC T-beam bridge. High strength, low relaxation steel wire ropes with minor radius, high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel wire ropes—including wire rope measuring, extruding anchor heads making, anchorage installing, tensioning steel wire ropes and pouring mortar was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on the concrete structure theory. The flexural strength of RC T-beam bridges strengthened with prestressed steel wire ropes was governed by the failure of concrete crushing. To investigate effectiveness of the strengthening method, fielding-load tests were carried out before and after strengthening. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved. The crack width measurement also indicates that this technique could increase the durability of the bridge. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

Effect of production management on semen quality during long-term storage in different European boar studs.

Science.gov (United States)

Schulze, M; Kuster, C; Schäfer, J; Jung, M; Grossfeld, R

2018-03-01

The processing of ejaculates is a fundamental step for the fertilizing capacity of boar spermatozoa. The aim of the present study was to identify factors that affect quality of boar semen doses. The production process during 1 day of semen processing in 26 European boar studs was monitored. In each boar stud, nine to 19 randomly selected ejaculates from 372 Pietrain boars were analyzed for sperm motility, acrosome and plasma membrane integrity, mitochondrial activity and thermo-resistance (TRT). Each ejaculate was monitored for production time and temperature for each step in semen processing using the special programmed software SEQU (version 1.7, Minitüb, Tiefenbach, Germany). The dilution of ejaculates with a short-term extender was completed in one step in 10 AI centers (n = 135 ejaculates), in two steps in 11 AI centers (n = 158 ejaculates) and in three steps in five AI centers (n = 79 ejaculates). Results indicated there was a greater semen quality with one-step isothermal dilution compared with the multi-step dilution of AI semen doses (total motility TRT d7: 71.1 ± 19.2%, 64.6 ± 20.0%, 47.1 ± 27.1%; one-step compared with two-step compared with the three-step dilution; P < .05). There was a marked advantage when using the one-step isothermal dilution regarding time management, preservation suitability, stability and stress resistance. One-step dilution caused significant lower holding times of raw ejaculates and reduced the possible risk of making mistakes due to a lower number of processing steps. These results lead to refined recommendations for boar semen processing. Copyright © 2018 Elsevier B.V. All rights reserved.

77 FR 27421 - Certain Steel Nails From the United Arab Emirates: Amended Final Determination of Sales at Less...

Science.gov (United States)

2012-05-10

... certain steel nails having a shaft length up to 12 inches. Certain steel nails include, but are not..., and have a variety of finishes, heads, shanks, point types, shaft lengths and shaft diameters... film tape backed with a heat seal adhesive; and Fasteners having a case hardness greater than or equal...

Stainless steel recycle FY94 progress report

International Nuclear Information System (INIS)

Imrich, K.J.

1994-01-01

The Materials Technology Section (MTS) of the Savannah River Technology Center (SRTC) was asked to demonstrate the practicality of recycling previously contaminated stainless steel components such as reactor heat exchanger heads, process water piping and slug buckets into 208 liters (55 gallon) drums and 2.8 cubic meter (100 ft 3 ) storage boxes. Radioactively contaminated stainless steel scrap will be sent to several industrial partners where it will be melted, decontaminated/cast into ingots, and rolled into plate and sheet and fabricated into the drums and boxes. As part of this recycle initiative, MTS was requested to demonstrate that radioactively contaminated Type 304L stainless steel could be remelted and cast to meet the applicable ASTM specification for fabrication of drums and boxes. In addition, MTS was requested to develop the technical basis of melt decontamination and establish practicality of using this approach for value added products. The findings presented in this investigation lead to the following conclusions: recycle of 18 wt% Cr-8 wt% Ni alloy can be achieved by melting Type 304 stainless steel in a air vacuum induction furnace; limited melt decontamination of the contaminated stainless steel was achieved, surface contamination was removed by standard decontamination techniques; carbon uptake in the as-cast ingots resulted from the graphite susceptor used in this experiment and is unavoidable with this furnace configuration. A new furnace optimized for melting stainless steel has been installed and is currently being tested for use in this program

Wear of ultra-high molecular weight polyethylene against damaged and undamaged stainless steel and diamond-like carbon-coated counterfaces.

Science.gov (United States)

Firkins, P; Hailey, J L; Fisher, J; Lettington, A H; Butter, R

1998-10-01

The wear of ultra-high molecular weight polyethylene (UHMWPE) in artificial joints and the resulting wear debris-induced osteolysis remains a major clinical concern in the orthopaedic sector. Third-body damage of metallic femoral heads is often cited as a cause of accelerated polyethylene wear, and the use of ceramic femoral heads in the hip is gaining increasing favour. In the knee prostheses and for smaller diameter femoral heads, the application of hard surface coatings, such as diamond-like carbon, is receiving considerable attention. However, to date, there has been little or no investigation of the tribology of these coatings in simulated biological environments. In this study, diamond-like carbon (DLC) has been compared to stainless steel in its undamaged form and following simulated third-body damage. The wear of UHMWPE was found to be similar when sliding against undamaged DLC and stainless steel counterfaces. DLC was found to be much more damage resistant than DLC. Under test conditions that simulate third-body damage to the femoral head, the wear of UHMWPE was seven times lower against DLC than against stainless steel (P < 0.05). The study shows DLC has considerable potential as a femoral bearing surface in artificial joints.

Fatigue Life Estimation of Medium-Carbon Steel with Different Surface Roughness

Directory of Open Access Journals (Sweden)

Changyou Li

2017-03-01

Full Text Available Medium-carbon steel is commonly used for the rail, wire ropes, tire cord, cold heading, forging steels, cold finished steel bars, machinable steel and so on. Its fatigue behavior analysis and fatigue life estimation play an important role in the machinery industry. In this paper, the estimation of fatigue life of medium-carbon steel with different surface roughness using established S-N and P-S-N curves is presented. To estimate the fatigue life, the effect of the average surface roughness on the fatigue life of medium-carbon steel has been investigated using 75 fatigue tests in three groups with average surface roughness (Ra: 0.4 μm, 0.8 μm, and 1.6 μm, respectively. S-N curves and P-S-N curves have been established based on the fatigue tests. The fatigue life of medium-carbon steel is then estimated based on Tanaka-Mura crack initiation life model, the crack propagation life model using Paris law, and material constants of the S-N curves. Six more fatigue tests have been conducted to validate the presented fatigue life estimation formulation. The experimental results have shown that the presented model could estimate well the mean fatigue life of medium-carbon steel with different surface roughness.

Clinical, serological and virological characteristics of an outbreak of paresis and neonatal foal disease due to equine herpesvirus-1 on a stud farm.

Science.gov (United States)

McCartan, C G; Russell, M M; Wood, J L; Mumford, J A

1995-01-07

An outbreak of equine herpesvirus-1 (EHV-1) occurred on a large stud farm with 133 mares, 54 foals and four stallions, and at least 85 mares, 22 foals and three stallions were infected. Clinical disease was observed in 16 mares, two stallions and 13 foals and the predominant clinical signs were scrotal oedema, ataxia and loss of libido in the stallions, ataxia and recumbency in the mares and uveitis and nasal discharge in the foals, although pneumonia and colic with intussusception were also recorded at autopsy. Neurological disease was more common in the mares nursing foals (12 of 38 infected) than in barren mares (one of 46 infected). Three mares died during the outbreak and no mares that had been recumbent bred again. Control procedures were based on virological and serological testing and stringent management practices to limit the spread of infection between groups of mares and foals and away from the stud farm. There were marked antibody responses in the adult horses, but they were generally poor in the foals; three of the nine viraemic foals did not develop significant increases in the levels of circulating antibody. Recommendations are made for the management of future outbreaks.

Development of laser cutting method for stainless steel liner

International Nuclear Information System (INIS)

Ishihara, Satoshi; Takahata, Masato; Wignarajah, Sivakumaran; Kamata, Hirofumi

2007-01-01

The present work is an attempt to develop a laser cutting method for cutting and removing stainless steel liners from concrete walls and floors in nuclear facilities. The effect of basic laser cutting parameters such as energy, cutting speed, assist gas flow etc. were first studied through cutting experiments on mock-up concrete specimens lined with 3mm thick stainless steel sheets using a 1kW Nd:YAG laser. These initial studies were followed by further studies on the effect of unevenness of the liner surface and on a new method of confining contamination during the cutting process using a sliding evacuation hood attached to the laser cutting head. The results showed that laser cutting is superior to other conventional cutting methods from the point of view of safety from radioactivity and work efficiency when cutting contaminated stainless steel liners. (author)

Magnetic property variation in carbon steel and chrome-molybdenum steel as a function of uniaxial stress noncoaxial with the magnetic field (abstract)

International Nuclear Information System (INIS)

Sablik, M.J.; Kaminski, D.A.; Jiles, D.C.; Biner, S.B.

1993-01-01

Magnescope 1 magnetic measurements were made on carbon steel specimens ranging from 0.1--0.8 wt %C and on chrome-molybdenum steel specimens cut from electric power plant pipes previously in service. The carbon steel specimens were heat-treated using three procedures: (1) spheroidization, (2) quenching, and (3) quench and tempering. The specimens were subjected to uniaxial tension up to 40 ksi. The inspection head was aligned so that the magnetic field was oriented at different angles with respect to the stress axis. Magnetic properties (such as coercivity and maximum differential permeability) were extracted from digitized magnetic hysteresis loop measurements. Magnetic properties were studied as a function of stress at each angle of stress-field orientation. To our knowledge, such a comprehensive study of noncoaxial stress and field effects has never been accomplished before for such a wide variety of steel specimens. Results for the various materials are presented for different orientation angles and compared to numerical results from the noncoaxial magnetomechanical hysteresis model of Sablik et al. 2

49 CFR 178.58 - Specification 4DA welded steel cylinders for aircraft use.

Science.gov (United States)

2010-10-01

... strain. (iv) Cross-head speed of the testing machine may not exceed 1/8 inch per minute during yield... tensile strength of the steel as determined from the physical and burst tests required and may not be over...

[Particle numbers in classified sizes of roadside dust caused by studded tires in the air at different heights from the pavement surface].

Science.gov (United States)

Sato, T; Niioka, T; Kurasaki, M; Kojima, Y

1996-07-01

Increased use of motor vehicles has produced various risks to human health due to air pollution by noxious gases, heavy metals and roadside dust. Since the late 1970s, the wide spread use of studded tires for cars has caused pavement wear, resulting in not only economic losses, but also roadside air pollution in cold and snowy regions in Japan. The most serious environmental problem in Sapporo, a city with heavy snowfall, in the 1980s, was roadside dust derived from studded tires. The inhabitants suffered from this dust in the early winter and in the early spring when the streets were not covered with snow. To investigate the influence of such roadside dust upon human health, particle numbers in classified sizes of roadside dust were counted after the roadside dust in the air was collected with a device we constructed at 30, 60, 90, 120, 150, and 180 cm above the pavement surface. The results indicated that the concentration of roadside dust in the air did not greatly vary according to the height from the pavement surface. The results also suggested that xenogranuloma, reported in lungs of stray dogs, under roadside dust-pollution conditions such as those examined here, may occur in humans in the future.

75 FR 34425 - Certain Steel Nails from the People's Republic of China: Final Results of the First New Shipper...

Science.gov (United States)

2010-06-17

... steel nails having a shaft length up to 12 inches. Certain steel nails include, but are not limited to... variety of finishes, heads, shanks, point types, shaft lengths and shaft diameters. Finishes include, but... length, and that are collated with adhesive or polyester film tape backed with a heat seal adhesive. Also...

Buckling Behavior of Cold-Formed Studs with Thermal Perforations

Directory of Open Access Journals (Sweden)

Garifullin Marsel

2016-01-01

Full Text Available Studies have shown that the optimal structural scheme for low-rise buildings that meets all regulatory requirements is a frame system. In this connection, thin-walled cold-formed steel (CFS profiles seem to be the best material for constructing light steel framed (LSF walls. The framework of LSF walls is usually constructed from CFS C-shaped profiles. To increase the thermal effectiveness of a wall, CFS profiles usually have thermal perforations and thus are called thermoprofiles. However, these openings have a negative impact on bearing capacity of profiles and require accurate evaluation. In this article a relatively new reticular-stretched thermoprofile with diamond-shaped openings is considered. The article deals with the buckling analysis of perforated CFS C-sections subjected to compression.

Effects of herd origin, AI stud and sire identification on genetic evaluation of Holstein Friesian bulls

Directory of Open Access Journals (Sweden)

Giovanni Bittante

2010-01-01

Full Text Available The purpose of this study was to estimate the effects of herd origin of bull, AI stud and sire identification number (ID  on official estimated breeding values (EBV for production traits of Holstein Friesian proven bulls. The data included 1,005  Italian Holstein-Friesian bulls, sons of 76 sires, born in 100 herds and progeny tested by 10 AI studs. Bulls were required  to have date of first proof between September 1992 and September 1997, to be born in a herd with at least one other  bull and to have sire and dam with official EBV when bull was selected for progeny testing. Records of sires with only one  son were also discarded. The dependent variable analyzed was the official genetic evaluation for a “quantity and quality  of milk” index (ILQ. The linear model to predict breeding values of bulls included the fixed class effects of herd origin of  bull, AI testing organization, birth year of bull, and estimated breeding values of sire and dam, both as linear covariates.  The R2of the model was 45% and a significant effect was found for genetic merit of sire (P   for herd origin of bull (P   nificant. The range of herd origin effect was 872 kg of ILQ. However, in this study, the causes of this result were not  clear; it may be due to numerous factors, one of which may be preferential treatment on dams of bulls. Analyses of resid-  uals on breeding value of proven bulls for ILQ showed a non significant effect of sire ID, after adjusting for parent aver-  age, herd origin effect and birth year effect. Although the presence of bias in genetic evaluation of dairy bulls is not evi-  dent, further research is recommended firstly to understand the reasons of the significant herd origin effect, secondly to  monitor and guarantee the greatest accuracy and reliability of genetic evaluation procedures. 

Seismic testing of a three-hour fire-rated steel-framed gypsum drywall partition for nuclear plants

International Nuclear Information System (INIS)

Thulin, F.A. Jr.

1983-01-01

The test specimen measured 1.22 by 3.05 m and consisted of three layers of 12.7 mm SHEETROCK Brand FIRECODE 'C' Gypsum Panels screw-attached to both sides of USG Steel 35SJ18 Studs 610 mm on centers. The specimen was first mounted in the earthquake simulator with the studs oriented horizontally and the runners vertically. Each runner was secured to a shaker support through which horizontal sinusoidal movement was induced normal to the surface of the wall. The damping ratio was found to be 9%. The average dynamic EI of the panel was 177000 GNxmm 2 . After the OBE scans, the specimen withstood the SSE scan for frequencies between 4 and 25 Hz. Resonance occured at 9 Hz. With a support acceleration of 3.0 gsub(e), the midspan acceleration reached 6.83 gsub(e). The same specimen was rotated 90 0 to a horizontal position with each runner attached to the corresponding shaker support which induced sinusoidal motion parallel to the runners. In the SSE shake at a frequency of 9 Hz and a support acceleration of 3.0 gsub(e), the midspan acceleration reached 4.66 gsub(e). To confirm the structural integrity of the specimen, it was then mounted in a vacuum chamber and tested in accordance with ASTM E 72. The rollers were spaced at 2.98 m. The panel yielded at a uniform load of 20.8 kN (equivalent to force at 8.8 gsub(e) acceleration) and failed at 26.3 kN (11.1 gsub(e)); both values greater than the 6.83 gsub(e) maximum dynamic midspan acceleration. The average static EI was 136000 GNxmm 2 - close to the 177000 GNxmm 2 dynamic EI. This transverse load test showed that the specimen was not structurally damaged by the shaker tests simulating earthquakes in nuclear plants. (orig./HP)

Mycotoxins in horse feed: Incidence of deoxynivalenol in oat samples from stud farms

Directory of Open Access Journals (Sweden)

Urošević Miroslav I.

2011-01-01

Full Text Available Reports concerning mycotoxins in horse feed are very rare and are typically restricted to fumonisins. As a non-ruminant monogastric species, horses may be more sensitive to adverse effects of mycotoxins, but the most severe effect of fumonisin B1 (FB1 in equines is that it causes fatal leucoencephalomalacia. In recent years, the European Food Safety Authority (EFSA has evaluated several mycotoxins as “undesirable substances in animal feed” with the aim of establishing guidance values for the feed industry. In its evaluation of deoxynivalenol (DON, EFSA concluded that this toxin exhibited toxic effects in all species, but that horses were more tolerant towards this toxin than pigs. According to the available data, a systematic survey on mycotoxins in horse feed in Serbia has not been published. Therefore, the aim of this study was to investigate the incidence of mycotoxins in horse feed in Vojvodina. Samples of oats for horse consumption, collected in 2010, were analyzed by enzyme immunoassays (ELISA for deoxynivalenol contamination. Twelve samples of oats were taken from twelve horse studs, with sport, school and hobby horses.

29 CFR 1926.754 - Structural steel assembly.

Science.gov (United States)

2010-07-01

... erection work being performed. (c) Walking/working surfaces—shear connectors and other similar devices—(1..., deformed anchors or threaded studs shall not be attached to the top flanges of beams, joists or beam... after the metal decking, or other walking/working surface, has been installed. (2) Installation of shear...

VVER vessel steel corrosion at interaction with molten corium in oxidizing atmosphere

Energy Technology Data Exchange (ETDEWEB)

Bechta, S.V. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation)], E-mail: bechta@sbor.spb.su; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Sulatsky, A.A. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Gusarov, V.V.; Almiashev, V.I. [Institute of Silicate Chemistry, Russian Academy of Sciences (ISCh RAS), St. Petersburg (Russian Federation); Lopukh, D.B. [SPb State Electrotechnical University (SPbGETU), St. Petersburg (Russian Federation); Bottomley, D. [EUROPAISCHE KOMMISSION, Joint Research Centre Institut fuer Transurane (ITU), Karlsruhe (Germany); Fischer, M. [AREVA NP GmbH, Erlangen (Germany); Piluso, P. [CEA/DEN/DSNI, Saclay (France); Miassoedov, A.; Tromm, W. [Forschungszentrum Karlsruhe, Karlsruhe (Germany); Altstadt, E. [Forschungszentrum Rossendorf (FZR), Dresden (Germany); Fichot, F. [IRSN/DPAM/SEMCA, St. Paul lez Durance (France); Kymalainen, O. [FORTUM Nuclear Services Ltd., Espoo (Finland)

2009-06-15

The long-term in-vessel corium retention (IVR) in the lower head bears a risk of the vessel wall deterioration caused by steel corrosion. The ISTC METCOR Project has studied physicochemical impact of prototypic coria having different compositions in air and steam and has generated valuable experimental data on vessel steel corrosion. It is found that the corrosion rate is sensitive to corium composition, but the composition of oxidizing above-melt atmosphere (air, steam) has practically no influence on it. A model of the corrosion process that integrates the experimental data, is proposed and used for development of correlations.

VVER vessel steel corrosion at interaction with molten corium in oxidizing atmosphere

International Nuclear Information System (INIS)

Bechta, S.V.; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Sulatsky, A.A.; Gusarov, V.V.; Almiashev, V.I.; Lopukh, D.B.; Bottomley, D.; Fischer, M.; Piluso, P.; Miassoedov, A.; Tromm, W.; Altstadt, E.; Fichot, F.; Kymalainen, O.

2009-01-01

The long-term in-vessel corium retention (IVR) in the lower head bears a risk of the vessel wall deterioration caused by steel corrosion. The ISTC METCOR Project has studied physicochemical impact of prototypic coria having different compositions in air and steam and has generated valuable experimental data on vessel steel corrosion. It is found that the corrosion rate is sensitive to corium composition, but the composition of oxidizing above-melt atmosphere (air, steam) has practically no influence on it. A model of the corrosion process that integrates the experimental data, is proposed and used for development of correlations.

Incident involving radioactive material in steel scrap

International Nuclear Information System (INIS)

Drabova, D.; Matzner, J.; Prouza, Z.

1998-01-01

In early March of 1996, a wagon with steel scrap heading from the Czech Republic to Italy was returned as a strongly contaminated material. Based on the integral dose (dose rate 650 mGy/h in front of the wagon) and spectrometric measurement and evaluation, it was concluded that an unshielded cobalt-60 source (1.6 TBq) was present. The history of the event (notification, assessment, intervention planning, intervention) is highlighted and the lesson learned from the incident is discussed. (P.A.)

Construction of low-cost, Mod-OA wood composite wind turbine blades

Science.gov (United States)

Lark, R. F.

1983-01-01

Two sixty-foot, low-cost, wood composite blades for service on 200 kW Mod-OA wind turbines were constructed. The blades were constructed of epoxy resin-bonded Douglas fir veneers for the leading edge sections, and paper honeycombcored, birch plywood faced panels for the afterbody sections. The blades were joined to the wind turbine hub by epoxy resin-bonded steel load take-off studs embedded into the root end of the blades. The blades were installed on the 200 kW Mod-OA wind turbine facility at Kahuku, Hawaii, The blades completed nearly 8,000 hours of operation over an 18 month period at an average power of 150 kW prior to replacement with another set of wood composite blades. The blades were replaced because of a corrosion failure of the steel shank on one stud. Inspections showed that the wood composite structure remained in excellent condition.

Strain rate effects in nuclear steels at room and higher temperatures

Energy Technology Data Exchange (ETDEWEB)

Solomos, G. E-mail: george.solomos@jrc.it; Albertini, C.; Labibes, K.; Pizzinato, V.; Viaccoz, B

2004-04-01

An investigation of strain rate, temperature and size effects in three nuclear steels has been conducted. The materials are: ferritic steel 20MnMoNi55 (vessel head), austenitic steel X6CrNiNb1810 (upper internal structure), and ferritic steel 26NiCrMo146 (bolting). Smooth cylindrical tensile specimens of three sizes have been tested at strain rates from 0.001 to 300 s{sup -1}, at room and elevated temperatures (400-600 deg. C). Full stress-strain diagrams have been obtained, and additional parameters have been calculated based on them. The results demonstrate a clear influence of temperature, which amounts into reducing substantially mechanical strengths with respect to RT conditions. The effect of strain rate is also shown. It is observed that at RT the strain rate effect causes up shifting of the flow stress curves, whereas at the higher temperatures a mild downshifting of the flow curves is manifested. Size effect tendencies have also been observed. Some implications when assessing the pressure vessel structural integrity under severe accident conditions are considered.

Genotyping in the Brazilian Criollo Horse Stud Book: resources and perspectives.

Science.gov (United States)

Costa, M A P; Bressel, R M C; Almeida, D B; Oliveira, P A; Bassini, L N; Moreira, C G A; Manzke, V H B; Siewerdt, F; Moreira, H L M

2010-08-24

The goal of this research was to evaluate the ability of the genotyping information available in the Brazilian Criollo Horse Stud Book to describe the genetic variability of the breed and the exclusion probability determined in comparative tests. Altogether, two softwares were used in the analyses of the available genotypes: Cervus 3.0.3 and Genepop 4.0. Eight microsatellite markers totaled 109 alleles, with an average of 13.6 +/- 0.6 alleles per locus. Large differences between expected and observed heterozygosity were ubiquitous (0.821 +/- 0.07 and 0.470 +/- 0.17, respectively). Although the estimated null allele frequency caused initial concern (0.284 +/- 0.199), it is likely that it was a reflection of the inbreeding coefficients found (0.432 +/- 0.184). All loci showed significant deviation from Hardy-Weinberg equilibrium, with heterozygote deficit (P < 0.0001) and genotypic linkage disequilibrium with at least one marker. The high polymorphic information content (0.798 +/- 0.088) could not warrant exclusion power for three loci (HMS7, HMS6 and HTG4) above 50% (0.491 +/- 0.158). However, combined exclusion probability reached 99.61%, a level close to ideal. The results demonstrate the excellent performance of the markers assessed in describing the genetic status of the breed and suggest the considerable ability to establish parentage.

Means for attaching remote handling tongs

International Nuclear Information System (INIS)

Kearney, A.S.

1982-01-01

A remote handling tong has a replaceable slave head assembly provided with a spring biased latch which engages a recess in a barrel member of the tong. The latch bolt extends transverse to the barrel member, and has studs which project at each end beyond the body of the slave head assembly so as to engage respective linear cam surfaces at a station for parking the slave head assembly. (author)

Metallurgical and acoustical characterization of a hydroformed, 304 stainless steel, Caribbean-style musical pan

International Nuclear Information System (INIS)

Murr, L.E.; Gaytan, S.M.; Lopez, M.I.; Bujanda, D.E.; Martinez, E.Y.; Whitmyre, G.; Price, H.

2008-01-01

We report herein the metallurgical and acoustical characterization of hydroformed 304 stainless steel, Caribbean pans. These pans were fully tuned to chromatic tones and compared to a manufactured, low-carbon, Caribbean steel pan standard. Hydroformed platforms had a Vickers microindentation hardness of HV 345, which was reduced by annealing during pan fabrication to HV 270. Skirts welded to the hydroformed head had a microindentation hardness of HV 440. Microstructural characterization by light optical metallography and transmission electron microscopy illustrated microstructures (including grain structures) characteristic of these pan microindentation hardnesses

Research on on-line monitoring technology for steel ball's forming process based on load signal analysis method

Science.gov (United States)

Li, Ying-jun; Ai, Chang-sheng; Men, Xiu-hua; Zhang, Cheng-liang; Zhang, Qi

2013-04-01

This paper presents a novel on-line monitoring technology to obtain forming quality in steel ball's forming process based on load signal analysis method, in order to reveal the bottom die's load characteristic in initial cold heading forging process of steel balls. A mechanical model of the cold header producing process is established and analyzed by using finite element method. The maximum cold heading force is calculated. The results prove that the monitoring on the cold heading process with upsetting force is reasonable and feasible. The forming defects are inflected on the three feature points of the bottom die signals, which are the initial point, infection point, and peak point. A novel PVDF piezoelectric force sensor which is simple on construction and convenient on installation is designed. The sensitivity of the PVDF force sensor is calculated. The characteristics of PVDF force sensor are analyzed by FEM. The PVDF piezoelectric force sensor is fabricated to acquire the actual load signals in the cold heading process, and calibrated by a special device. The measuring system of on-line monitoring is built. The characteristics of the actual signals recognized by learning and identification algorithm are in consistence with simulation results. Identification of actual signals shows that the timing difference values of all feature points for qualified products are not exceed ±6 ms, and amplitude difference values are less than ±3%. The calibration and application experiments show that PVDF force sensor has good static and dynamic performances, and is competent at dynamic measuring on upsetting force. It greatly improves automatic level and machining precision. Equipment capacity factor with damages identification method depends on grade of steel has been improved to 90%.

Seismic behavior and design of a primary shield structure consisting of steel-plate composite (SC) walls

Energy Technology Data Exchange (ETDEWEB)

Booth, Peter N., E-mail: boothpn@purdue.edu [Lyles School of Civil Engineering, Purdue University, W. Lafayette, IN (United States); Varma, Amit H., E-mail: ahvarma@purdue.edu [Lyles School of Civil Engineering, Purdue University, W. Lafayette, IN (United States); Sener, Kadir C., E-mail: ksener@purdue.edu [Lyles School of Civil Engineering, Purdue University, W. Lafayette, IN (United States); Mori, Kentaro, E-mail: kentaro_mori@mhi.co.jp [Mitsubishi Heavy Industries, Ltd, Kobe (Japan)

2015-12-15

This paper presents an analytical evaluation of the seismic behavior and design of a unique primary shield (PSW) structure consisting of steel-plate composite (SC) walls designed for a typical pressurized water reactor (PWR) nuclear power plant. Researchers in Japan have previously conducted a reduced (1/6th) scale test of a PSW structure to evaluate its seismic (lateral) load-deformation behavior. This paper presents the development and benchmarking of a detailed 3D nonlinear inelastic finite element (NIFE) model to predict the lateral load-deformation response and behavior of the 1/6th scale test structure. The PSW structure consists of thick SC wall segments with complex and irregular geometry that surround the central reactor vessel cavity. The wall segments have three layers of steel plates (one each on the interior and exterior surfaces and one embedded in the middle) that are anchored to the concrete infill with stud anchors. The results from the 3D NIFE analyses include: (i) the lateral load-deformation behavior of the PSW structure, (ii) the progression of yielding in the steel plates, concrete cracking, formation of compression struts, and (iii) the final failure mode. These results are compared and benchmarked using experimental measurements and observations reported by Shodo et al. (2003). The analytical results provide significant insight into the lateral behavior and strength of the PSW structure, and are used for developing a design approach. This design approach starts with ACI 349 code equations for reinforced concrete shear walls and modifies them for application to the PSW structure. A simplified 3D linear elastic finite element (LEFE) model of the PSW structure is also proposed as a conventional structural analysis tool for estimating the design force demands for various load combinations.

Seismic behavior and design of a primary shield structure consisting of steel-plate composite (SC) walls

International Nuclear Information System (INIS)

Booth, Peter N.; Varma, Amit H.; Sener, Kadir C.; Mori, Kentaro

2015-01-01

This paper presents an analytical evaluation of the seismic behavior and design of a unique primary shield (PSW) structure consisting of steel-plate composite (SC) walls designed for a typical pressurized water reactor (PWR) nuclear power plant. Researchers in Japan have previously conducted a reduced (1/6th) scale test of a PSW structure to evaluate its seismic (lateral) load-deformation behavior. This paper presents the development and benchmarking of a detailed 3D nonlinear inelastic finite element (NIFE) model to predict the lateral load-deformation response and behavior of the 1/6th scale test structure. The PSW structure consists of thick SC wall segments with complex and irregular geometry that surround the central reactor vessel cavity. The wall segments have three layers of steel plates (one each on the interior and exterior surfaces and one embedded in the middle) that are anchored to the concrete infill with stud anchors. The results from the 3D NIFE analyses include: (i) the lateral load-deformation behavior of the PSW structure, (ii) the progression of yielding in the steel plates, concrete cracking, formation of compression struts, and (iii) the final failure mode. These results are compared and benchmarked using experimental measurements and observations reported by Shodo et al. (2003). The analytical results provide significant insight into the lateral behavior and strength of the PSW structure, and are used for developing a design approach. This design approach starts with ACI 349 code equations for reinforced concrete shear walls and modifies them for application to the PSW structure. A simplified 3D linear elastic finite element (LEFE) model of the PSW structure is also proposed as a conventional structural analysis tool for estimating the design force demands for various load combinations.

Design of SC walls and slabs for impulsive loading

Energy Technology Data Exchange (ETDEWEB)

Varma, Amit H. [Purdue Univ., West Lafayette, IN (United States)

2015-11-11

Reinforced concrete (RC) structures have historically been the preferred choice for blast resistant structures because of their mass and the ductility provided by steel reinforcement. Steel-plate composite (SC) walls are a viable alternative to RC for protecting the infrastructure against explosive threats. SC structures consist of two steel faceplates with a plain concrete core between them. The steel faceplates are anchored to the concrete using stud anchors and connected to each other using tie bars. SC structures provide mass from the concrete infill and ductility from the continuous external steel faceplates. This dissertation presents findings and recommendations from experimental and analytical investigations of the performance of SC walls subjected to far-field blast loads.

Topical problems of crackability in weld annealing of low-alloyed pressure vessel steels

International Nuclear Information System (INIS)

Holy, M.

1977-01-01

The following method was developed for determining annealing crackability: A sharp notch was made in the middle of the bodies of rods imitated in a welding simulator. Chucking heads were modified such as to permit chucking a rod in an austenitic block by securing the nut. Prestress was controlled by button-headed screw adapters. The blocks were made of 4 types of austenitic steels with graded thermal expansivity coefficients, all higher than that of the tested low-alloyed steel rod. The blocks with rods were placed in a furnace and heated at a rate of 100 degC/h. As a result of the larger austenite block diameter the rod began to be stretched and at some temperature of more than 500 degC it was pulled apart. The risk of annealing crackability of welded joints may be reduced by the choice of material and melt and by the technology of welding, mainly by the choice of a suitable addition material in whose weld metal the plastic deformation preferably takes place in annealing. (J.P.)

In vitro analysis of the marginal adaptation and discrepancy of stainless steel crowns

Science.gov (United States)

Mulder, Riaan; Medhat, Rasha; Mohamed, Nadia

2018-01-01

Abstract Aim: The purpose of the study was to assess the marginal adaptation and discrepancy of SSC’s. Differences in adaptation and discrepancy between the four surfaces (mesial, lingual, distal, and buccal) were evaluated. Methods: The placement of stainless steel crowns were completed on a phantom head in accordance with the clinical technique. The ideal tooth preparation was made and this ‘master tooth’ duplicated to achieve a sample size of 15. The stainless steel crowns were placed, trimmed, and cemented as per the clinical technique. The cemented stainless crowns were analyzed under 100× stereomicroscope magnification. The marginal adaptation and discrepancy of each specimen was measured every 2 µm. Results: All the specimens showed marginal adaptation and discrepancy. The lingual margin had a significantly better adaptation (p steel crown adaptation and discrepancy is an essential clinical step. PMID:29536024

Do oxidized zirconium femoral heads reduce polyethylene wear in cemented THAs? A blinded randomized clinical trial.

Science.gov (United States)

Zaoui, Amine; Hage, Samer El; Langlois, Jean; Scemama, Caroline; Courpied, Jean Pierre; Hamadouche, Moussa

2015-12-01

Charnley low-friction torque total hip arthroplasty (THA) remains the gold standard in THA. The main cause for failure is wear of the socket. Highly crosslinked polyethylene (HXLPE) has been associated with reduced wear rates. Also, oxidized zirconium has shown in vitro reduced wear rates. However, to our knowledge, there are no data comparing oxidized zirconium femoral heads with metal heads against HXLPE or ultrahigh-molecular-weight polyethylene (UHMWPE) when 22.25-mm bearings were used, which was the same size that performed so well in Charnley-type THAs. We hypothesized that after a minimal 4-year followup (1) use of HXLPE would result in lower radiographic wear than UHMWPE when articulating with a stainless steel head or with an oxidized zirconium head; (2) use of oxidized zirconium would result in lower radiographic wear than stainless steel when articulating with UHMWPE and HXLPE; and (3) there would be no difference in terms of Merle d'Aubigné scores between the bearing couple combinations. One hundred patients were randomized to receive cemented THA with either oxidized zirconium or a stainless steel femoral head. UHMWPE was used in the first 50 patients, whereas HXLPE was used in the next 50 patients. There were 25 patients in each of the four bearing couple combinations. All other parameters were identical in both groups. Complete followup was available in 86 of these patients. Femoral head penetration was measured using a validated computer-assisted method dedicated to all-polyethylene sockets. Clinical results were compared between the groups using the Merle d'Aubigné score. In the UHMWPE series, the median steady-state penetration rate from 1 year onward was 0.03 mm/year (range, 0.003-0.25 mm/year) in the oxidized zirconium group versus 0.11 mm/year (range, 0.03-0.29 mm/year) in the metal group (difference of medians 0.08, p zirconium group versus 0.05 mm/year (range, -0.39 to 0.11 mm/year) in the metal group (difference of medians 0.03, p

Properties and Microstructure of Laser Welded VM12-SHC Steel Pipes Joints

Directory of Open Access Journals (Sweden)

Skrzypczyk A.

2016-06-01

Full Text Available Paper presents results of microstructure and tests of welded joints of new generation VM12-SHC martensitic steel using high power CO2 laser (LBW method with bifocal welding head. VM12-SHC is dedicated to energetic installation material, designed to replace currently used. High content of chromium and others alloying elements improve its resistance and strength characteristic. Use of VM12-SHC steel for production of the superheaters, heating chambers and walls in steam boilers resulted in various weldability researches. In article are presented results of destructive and non-destructive tests. For destructive: static bending and Vickers hardness tests, and for non-destructive: VT, RT, UT, micro and macroscopic tests were performed.

Experimental tests on buckling of torispherical heads comparison with plastic bifurcation analysis

International Nuclear Information System (INIS)

Roche, R.L.; Autrusson, B.

1984-06-01

Sixteen torispherical heads have been tested under internal pressure. All these heads were made by cold spinning from mild steel plates. Deflections on the axis and in the knuckle region have been recorded. As an practical result of these experiments, buckling pressure is given for each tested head. It is also indicated the maximum pressure reached during the tests, this pressure is very higher than the buckling pressure. It is also seen that buckling pressure is little sensitive to initial geometric imperfections. These experimental buckling pressure are compared with computation results obtained by plastic bifurcation analysis. Five different models of bifurcation matrix have been considered. If tangent matrix is unconservative, the use of tangent modulus (in lieu of YOUNG's modulus) is overconservative. Finally a mixing of tangent normal modulus and secant shearing modulus seems to be a good enough model (not to far from experimental results, and with not to large standard deviation)

Experiment and simulation analysis of roll-bonded Q235 steel plate

International Nuclear Information System (INIS)

Zhao, G.; Huang, Q.; Zhou, C.; Zhang, Z.; Ma, L.; Wang, X.

2016-01-01

Heavy-gauge Q235 steel plate was roll bonded, and the process was simulated using MARC software. Ultrasonic testing results revealed the presence of cracks and lamination defects in an 80-mm clad steel sheet, especially at the head and tail of the steel plate. There were non-uniform ferrite + pearlite microstructures and unbound areas at a bond interface. Through scanning electron microscopy analysis, long cracks and additional inclusions in the cracks were observed at the interface. A fracture analysis revealed non-uniform inclusions that pervaded the interface. Moreover, MARC simulations demonstrated that there was little equivalent strain at the centre of the slab during the first rolling pass. The equivalent centre increased to 0.5 by the fourth rolling pass. Prior to the final pass, the equivalent strain was not consistent across the thickness direction, preventing bonding interfaces from forming consistent deformation and decreasing the residual stress. The initial rolling reduction rate should not be very small (e.g. 5%) as it is averse to the coordination of rolling deformation. Such rolling processes are averse to the rolling bond. (Author)

Locating the displacement of the steel wire implantation with the stereotactic mammography

International Nuclear Information System (INIS)

Ma Jie; Xu Jianmin; Sun Guomin; Sun Guoping; Zang Da; Zhou Dongxian; Mai Peicheng

2007-01-01

Objective: To analyze the manifestation, reason, the processing method of the steel wire implantation with the stereotactic mammography to improve the accuracy of the preoperative positioning. Methods: Seventy-nine cases which got the stereotactic steel wire implantation. In 96 lesions, 13 had steel wire displacement. Among them, 5 cases got steel wire displacement during the stereotactic process, 5 cases got steel wire displacement after the stereotactic process, 2 cases got steel wire displacement during the operation, one case did not show the calcification on the postoperative radiography. Results: The steel wire displacement occurred in 5 cases during the stereotactic process came from the patients and doctors respectively and the repositioning was needed. The steel wire displacement after the stereoscopic positioning was attributed to the overdose injection of local anesthesia, which led to the mismatch between the depth of Z axis of the mammary gland and the actual depth the computer given, the incorrect method for needle placement, and, neglecting whether the steel wire have got the lesion anchored when pulling out the needle set of steel wire hood, besides, these three kinds of instances above were all exaggerated by the accordion effect. For the displacement within 2 cm, the lesion can be excised toward the pathological change direction according to the position that steel wire prompted and re-place the second steel wire, putting the J-shaped steel wire into the needle hood and taking it out of the body. After repositioning, 2 cases had the steel wire prolapse during operation, which resulted from the over-lifting of the steel wire. After placing the steel wire, the radiologist should give an accurate description on the depth and direction to the surgeon and the notch should be taken for incision from the steel wire head end which is proximate to skin. The postoperative specimen from one case had no calcification, which might be related to the condition

Cylindrically guided wave technique for detection of stress corrosion cracking and corrosion wastage in long stud-bolts

International Nuclear Information System (INIS)

Light, G.M.; Joshi, N.R.

1986-01-01

The authors discuss how, when performing an ultrasonic inspection of a cylindrical body, the sound waves, or pulses, will interact with the boundaries of the cylinder and produce mode-converted as well as normal longitudinal waves. The elastic energy of the wave propagating along the length of the cylinder is concentrated and produces strong echoes from shallow defects in the specimen. In threaded specimens, the guided wave produces signals from the threads that can be differentiated from defects in the cylinder. This paper reports on a study using the guided wave theory conducted to determine the optimum inspection transducer size and frequency relative to stud-bolt diameter and length. Bolts ranging from 25 to 285 cm (10 to 112 in.) in length and 2.5 to 11.5 cm (1 to 4.5 in.) in diameter were tested. For all cases, theoretical predictions agreed well with the experimental data. In this paper, the theory, experimental apparatus, and testing results are discussed

The effects of a common stainless steel orthodontic bracket on the diagnostic quality of cranial and cervical 3T- MR images: a prospective, case-control study.

Science.gov (United States)

Cassetta, Michele; Pranno, Nicola; Stasolla, Alessandro; Orsogna, Nicola; Fierro, Davide; Cavallini, Costanza; Cantisani, Vito

2017-08-01

To evaluate the effect of orthodontic stainless steel brackets and two different types of archwires on the diagnostic quality of 3-T MR images. This prospective, case-control study was conducted following Strengthening the Reporting of Observational Studies in Epidemiology guidelines. The recruitment was conducted among orthodontic patients. 80 subjects, requiring MRI for the presence of temporomandibular disorders, were enrolled and divided into four groups: 20 patients using aligners (control group); 20 patients with stainless steel brackets without archwires; 20 patients with stainless steel brackets and nickel-titanium archwires; and 20 patients with stainless steel brackets and stainless steel archwires. Two experts in neuroradiology evaluated the images to determine the amount of distortion in 6 regions and 48 districts. A score was subjectively assigned according to a modified receiver operating characteristic method of distortion classification. Any disagreement was resolved through consensus seeking; when this was not possible, a third neuroradiologist was consulted. The following statistical methods were used: descriptive statistics, Cohen's kappa coefficient (k), Kruskal-Wallis test, pairwise comparisons using the Dunn-Bonferroni approach. The significance was set at p ≤ 0.05. The presence of stainless steel brackets with or without archwires negatively influenced MRI of the cervical region, paranasal sinuses, head and neck region, and cervical vertebrae but did not influence MRI of brain and temporomandibular joint regions. Patients with a stainless steel multibracket orthodontic appliance should remove it before cervical vertebrae, cervical region, paranasal sinuses, and head and neck MRI scans. The brain and temporomandibular joint region MRI should not require the removal of such appliances.

Heading and head injuries in soccer.

Science.gov (United States)

Kirkendall, D T; Jordan, S E; Garrett, W E

2001-01-01

In the world of sports, soccer is unique because of the purposeful use of the unprotected head for controlling and advancing the ball. This skill obviously places the player at risk of head injury and the game does carry some risk. Head injury can be a result of contact of the head with another head (or other body parts), ground, goal post, other unknown objects or even the ball. Such impacts can lead to contusions, fractures, eye injuries, concussions or even, in rare cases, death. Coaches, players, parents and physicians are rightly concerned about the risk of head injury in soccer. Current research shows that selected soccer players have some degree of cognitive dysfunction. It is important to determine the reasons behind such deficits. Purposeful heading has been blamed, but a closer look at the studies that focus on heading has revealed methodological concerns that question the validity of blaming purposeful heading of the ball. The player's history and age (did they play when the ball was leather and could absorb significant amounts of water), alcohol intake, drug intake, learning disabilities, concussion definition and control group use/composition are all factors that cloud the ability to blame purposeful heading. What does seem clear is that a player's history of concussive episodes is a more likely explanation for cognitive deficits. While it is likely that the subconcussive impact of purposeful heading is a doubtful factor in the noted deficits, it is unknown whether multiple subconcussive impacts might have some lingering effects. In addition, it is unknown whether the noted deficits have any affect on daily life. Proper instruction in the technique is critical because if the ball contacts an unprepared head (as in accidental head-ball contacts), the potential for serious injury is possible. To further our understanding of the relationship of heading, head injury and cognitive deficits, we need to: learn more about the actual impact of a ball on the

76 FR 30101 - Certain Steel Nails From the People's Republic of China: Final Results of Antidumping Duty...

Science.gov (United States)

2011-05-24

... shaft length up to 12 inches. Certain steel nails include, but are not limited to, nails made of round... finishes, heads, shanks, point types, shaft lengths and shaft diameters. Finishes include, but are not... collated with adhesive or polyester film tape backed with a heat seal adhesive. Also excluded from the...

Dynamic thermal baffle on lower head of FBR sodium-sodium intermediate heat exchanger

International Nuclear Information System (INIS)

Charbonnel, A.; Foussat, C.

1981-01-01

The cover head of the heat exchanger is bathed on the one side by the primary sodium of the 'cold' header of the vessel and on the other side by the secondary sodium which feeds the heat exchange tube bank through the lower tubesheet. In the case of transient or permanent operating conditions at partial ratings, there are large temperature differences between the inner sodium (inlet temperature conditions of secondary sodium) and the outer sodium (mean temperature conditions in the primary sodium outlet port), hence the necessity of designing a thermal baffle which protects the head and its connection to the tubesheet. A 'static' thermal baffle consisting of a thick steel plate enclosing static sodium around the head proves inadequate during transient operating conditions. This is why a 'dynamic' thermal baffle is used whose design is based on the fact that the primary sodium in the lower part of the outlet port is always at a temperature close to that of the secondary sodium in the inlet header and the head. The primary sodium is taken from the bottom of the outlet port by a ring deflector and circulates in an annulus created by a double housing and the head. It flows out through openings in the lower part of the housing. (orig./GL)

THE ABSOLUTE GROWTH AND THE GROWTH COEFFICIENTS OF THE MAIN CORPORAL SIZES ON ACTUAL YOUTH ARDENEZ MALE COMPARED WITH THE YOUTH ARDENEZ MALE BREED IN 2002 ON IZVIN STUD, TIMIS DISTRICT

Directory of Open Access Journals (Sweden)

I. TĂPĂLAGĂ

2009-10-01

Full Text Available The purpose of this paper is to observe the development degree under the morphological aspect at Ardenez horses from Izvin Stud. For this we have observed 8 exterior indicators on horses starting from 0-6 months to adult ones.The research was made on strength of 49 horses Ardenez thoroughbred, where absolute growth and the growth coefficients of the main corporal dimensions were calculated for the actual young Ardenez horses, compared with the absolute growth and the growth coefficients of the main corporal dimensions for young Ardenez horses raised in 2002 at Izvin Stud.As a result of the research, we’ve find that the growth of the main corporal dimensions on young horses is influenced by internal and external factors.From the internal factors, the precocity specific for the heavy thoroughbred, has influence upon the growth of the main corporal dimensions, thus at the age of 3, some of this dimensions stop their growth.A special influence upon the growth is exerted by the appearance of the sexual maturity, factor that makes corporal dimensions to vary between sexes, after the installation of the secondary sexual characters.

Microbial-Influenced Corrosion of Corten Steel Compared with Carbon Steel and Stainless Steel in Oily Wastewater by Pseudomonas aeruginosa

Science.gov (United States)

Mansouri, Hamidreza; Alavi, Seyed Abolhasan; Fotovat, Meysam

2015-07-01

The microbial corrosion behavior of three important steels (carbon steel, stainless steel, and Corten steel) was investigated in semi petroleum medium. This work was done in modified nutrient broth (2 g nutrient broth in 1 L oily wastewater) in the presence of Pseudomonas aeruginosa and mixed culture (as a biotic media) and an abiotic medium for 2 weeks. The behavior of corrosion was analyzed by spectrophotometric and electrochemical methods and at the end was confirmed by scanning electron microscopy. The results show that the degree of corrosion of Corten steel in mixed culture, unlike carbon steel and stainless steel, is less than P. aeruginosa inoculated medium because some bacteria affect Corten steel less than other steels. According to the experiments, carbon steel had less resistance than Corten steel and stainless steel. Furthermore, biofilm inhibits separated particles of those steels to spread to the medium; in other words, particles get trapped between biofilm and steel.

ESTIMATION OF IRREVERSIBLE DAMAGEABILITY AT FATIGUE OF CARBON STEEL

Directory of Open Access Journals (Sweden)

I. O. Vakulenko

2014-04-01

Full Text Available Purpose. Damageability estimation of carbon steel in the conditions of cyclic loading. Methodology. The steel fragments of railway wheel rim and rail head served as material for research with chemical composition 0.65 % С, 0.67 % Mn, 0.3 % Si, 0.027 % P, 0.028 % S и 0.7 % C, 0.82 % Mn, 0.56 % Si, 0.025 % P, 0.029 % S accordingly. The microstructure of tested steels corresponded to the state of metal after a hot plastic deformation. The fatigue research was conducted in the conditions of symmetric bend using the proof-of-concept machine of type «Saturn-10». Full Wohler diagrams and the lines corresponding to forming of sub-and micro cracks were constructed. The distribution analysis of internal stresses in the metal under cyclic loading was carried out using the microhardness tester of PMT-3 type.Findings. On the basis of fatigue curves for high-carbon steels analysis the positions of borders dividing the areas of convertible and irreversible damages were determined. The article shows that with the growth of carbon concentration in the steel at invariability of the structural state an increase of fatigue limit is observed. At the same time the acceleration of processes, which determine transition terms from the stage of forming of submicrocracks to the microcracks occurs. The research of microhardness distribution in the metal after destruction confirmed the nature of carbon amount influence on the carbon steel characteristics. Originality. Regardless on the stages of breakdown site forming the carbon steels behavior at a fatigue is determined by the ration between the processes of strengthening and softening. At a cyclic loading the heterogeneity of internal stresses distribution decreases with the increase of distance from the destruction surface. Analysis of metal internal restructuring processes at fatigue loading made it possible to determine that at the stages prior to incubation period in the metal microvolumes the cells are already

Hot cracking of welded joints of the 7CrMoVTiB 10-10 (T/P24) steel

Energy Technology Data Exchange (ETDEWEB)

Adamiec, J, E-mail: janusz.adamiec@polsl.pl [Department of Materials Science, Silesian University of Technology, Krasinskiego 8, 40-019 Katowice (Poland)

2011-05-15

Bainitic steel 7CrMoVTiB10-10 is one the newest steels for waterwalls of modern industrial boilers. In Europe, attempts have been made to make butt welded joints of pipes made of this steel of the diameter up to 51 mm and thickness up to 8 mm. Many cracks have been observed in the welded joint, both during welding and transport and storage. The reasons of cracking and the prevention methods have not been investigated. No comprehensive research is carried out in Europe in order to automate the welding process of the industrial boiler elements made of modern bainitic steel, such as 7CrMoVTiB10-10. There is no information about its overall, operative and local weldability, influence of heat treatment, as well as about resistance of the joints to cracking during welding and use. The paper presents experience of Energoinstal SA from development of technology and production of waterwalls of boilers made of the 7CrMoVTiB 10-10 steel on a multi-head automatic welder for submerged arc welding.

77 FR 12556 - Certain Steel Nails From the People's Republic of China: Final Results and Final Partial...

Science.gov (United States)

2012-03-01

... nails having a shaft length up to 12 inches. Certain steel nails include, but are not limited to, nails... variety of finishes, heads, shanks, point types, shaft lengths and shaft diameters. Finishes include, but... adhesive or polyester film tape backed with a heat seal adhesive. Also excluded from the scope of this...

Aircraft Steels

Science.gov (United States)

2009-02-19

component usage. PH 13-8Mo is a precipitation-hardenable martensitic stainless steel combining excellent corrosion resistance with strength. Custom 465 is...a martensitic , age-hardenable stainless steel capable of about 1,724 MPa (250 ksi) UTS when peak-aged (H900 condition). Especially, this steel can...NOTES 14. ABSTRACT Five high strength steels (4340, 300M, AerMet 100, Ferrium S53, and Hy-Tuf) and four stainless steels (High Nitrogen, 13

Steel making

CERN Document Server

Chakrabarti, A K

2014-01-01

"Steel Making" is designed to give students a strong grounding in the theory and state-of-the-art practice of production of steels. This book is primarily focused to meet the needs of undergraduate metallurgical students and candidates for associate membership examinations of professional bodies (AMIIM, AMIE). Besides, for all engineering professionals working in steel plants who need to understand the basic principles of steel making, the text provides a sound introduction to the subject.Beginning with a brief introduction to the historical perspective and current status of steel making together with the reasons for obsolescence of Bessemer converter and open hearth processes, the book moves on to: elaborate the physiochemical principles involved in steel making; explain the operational principles and practices of the modern processes of primary steel making (LD converter, Q-BOP process, and electric furnace process); provide a summary of the developments in secondary refining of steels; discuss principles a...

Effects of various treatments on the serviceability of water-immersed carbon-steel ball bearings

International Nuclear Information System (INIS)

Wensel, R.G.

1977-06-01

Carbon-steel ball bearings employing various coatings, surface treatments, lubricants and ball and separator materials were tested under conditions simulating those in the NPD/Bruce type fuelling machine heads. The effects of the treatments on operating torques and wear and corrosion rates were studied. Sealed bearings lubricated with Dow FS 3451 (a fluorosilicone grease) gave the best performance in terms of these parameters. (author)

Re-utilization by '' Stud Welding'' of capsules charpy-V belonged to surveillance programs

International Nuclear Information System (INIS)

Lapena, J.; Perosanz, F. J.; Gachuz, M.

1998-01-01

The perspectives of nuclear plants life extension that are approximating to their end of design life compels to make new surveillance programs. The re-utilization of specimens belonging to surveillance capsules already tested in these new surveillance programs seems be a solution worldwide accepted. The two possible re-utilization processes of this irradiated material are: Subsized specimens and Reconstitution. While the first alternative (Subsized specimens) outlines serious problems for apply the results, the reconstitution eliminates this problem, since the resulting specimens after of the reconstruction procedure would be of the same dimensions that the original. The reconstruction process involves welds, and therefore it has associated the specific problems of this type of joints. Furthermore, by be tried to material irradiated with certain degree of internal damage, that is the variable to evaluate, requires that the heat contribution to the piece not originate local thermal treatments that alter its mechanical qualities. In this work has been followed the evolution by the variables of the weld process and their influence on the quality by the union from metallographic al point of view as well as mechanical for a weld procedure by Stud Welding. The principal objective is to optimize said parameters to assure a good mechanical continuity, without detriment of the microstructural characteristics of the original material. To verify this last have been accomplished with metallographical tests, temperature profile, hardness and will be carried out also Charpy tests. (Author)

Some considerations on the toughness properties of ferritic stainless steels - A brief review

CSIR Research Space (South Africa)

Van Zwieten, ACTM

1993-02-01

Full Text Available . H. Bulloch* Head Office, Electricity Supply Board, Lower Fitzwilliam Street, Dublin 2, Republic of Ireland (Received 14 February 1992; accepted 25 February 1992) A BS TRA C T The present paper has attempted... of molybdenum, niobium or titanium. Recently, very low (C + N) content have been specified; the super-ferritic steels. The higher alloy compositions can also include up to 4% Ni, provided this does not alter their fully...

A Study on the Coupled FEM-Analysis for Reactor Vessel Lower Head of APR1400 under the Severe Accident Scenario

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyonam; Namgung, Ihn [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2014-10-15

For the stabilization of the RPV the in-vessel retention strategy with external reactor vessel cooling (IVR-ERVC) is adopted in APR1400. Under this severe accident condition, a good understanding of the mechanical behavior of the reactor vessel lower head (RVLH) is necessary both for verification of structural integrity and for improving the design applying appropriate accident mitigation strategies. The purpose of this study is to develop the analysis method of the RVLH with thermo-mechanical analysis using FEM tool (ANSYS v.15) in case of core-melting severe accident condition, and then analyze the RVLH of APR1400 including creep behavior. The plastic strain can be the major cause of lower head failure on the reactor vessel, and the creep cannot be not negligible factor of the failure under the severe accident condition. In the study, we applied constant convection coefficient at assumed temperature on the outside wall of RPV and substitute creep data of SA-508. In addition, it was found that the steel ablation at the interface between corium and vessel steel is not only a thermal phenomenon in the METCOR experiments. Corrosion processes and the formation of eutectics lead to the erosion of the vessel steel at temperatures that are significantly lower than the melting temperature of steel. It called thermo-chemical attack of the corium (corrosion). Reduced wall thickness because of the thermo-chemical effect by corium increase the equivalent plastic strain, and decrease the minimum time to reach 20% creep strain.

The management of steel industry by-products and waste

Energy Technology Data Exchange (ETDEWEB)

1987-01-01

The report considers the management of solid and semi-solid wastes that are reused or disposed of outside steelworks. Headings are: introduction; ironmaking slags (including generation, properties, processing, uses and disposal); (steelmaking slag from hot metal pretreatment, and primary and secondary steelmaking); ironmaking dust and sludges; steelmaking dust and sludges; millscale and sludge from continuous casting and rolling mills; treatment and handling of used oils and greases; refractory waste from refining of metallurgical furnaces and vessels; by-products, waste and wastewater arising from coke oven batteries; treatment of stainless steel waste; characterisation of waste by leaching tests; dumping technology; and conclusions.

Lower limb and associated injuries in frontal-impact road traffic ...

African Journals Online (AJOL)

Abstract. Objectives: To study the relationship between severity of injury of the lower limb and severity of injury of the head, thoracic, and abdominal regions in frontal-impact road traffic collisions. Methods: Consecutive hospitalised trauma patients who were involved in a frontal road traffic collision were prospectively stud-.

The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (Ⅲ) - Comparison on Laser Weldability of Boron Steel and Hot -Stamped Steel-

Energy Technology Data Exchange (ETDEWEB)

Choi, So Young; Kim, Jong Do [Korea Maritime and Ocean University, Busan (Korea, Republic of); Kim, Jong Su [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of)

2015-01-15

This study was conducted to compare the laser weldability of boron steel and hot-stamped steel. In general, boron steel is used in the hot-stamping process. Hot-stamping is a method for simultaneously forming and cooling boron steel in a press die after heating it to the austenitizing temperature. Hot-stamped steel has a strength of 1500 MPa or more. Thus, in this study, the laser weldability of boron steel and that of hot-stamped steel were investigated and compared. A continuous wave disk laser was used to produce butt and lap joints. In the butt welding, the critical cooling speed at which full penetration was obtained in the hot-stamped steel was lower than that of boron steel. In the lap welding, the joint widths were similar regardless of the welding speed when full penetration was obtained.

The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (Ⅲ) - Comparison on Laser Weldability of Boron Steel and Hot -Stamped Steel-

International Nuclear Information System (INIS)

Choi, So Young; Kim, Jong Do; Kim, Jong Su

2015-01-01

This study was conducted to compare the laser weldability of boron steel and hot-stamped steel. In general, boron steel is used in the hot-stamping process. Hot-stamping is a method for simultaneously forming and cooling boron steel in a press die after heating it to the austenitizing temperature. Hot-stamped steel has a strength of 1500 MPa or more. Thus, in this study, the laser weldability of boron steel and that of hot-stamped steel were investigated and compared. A continuous wave disk laser was used to produce butt and lap joints. In the butt welding, the critical cooling speed at which full penetration was obtained in the hot-stamped steel was lower than that of boron steel. In the lap welding, the joint widths were similar regardless of the welding speed when full penetration was obtained

Heads Up

Science.gov (United States)

... Connect with Us HEADS UP Apps Reshaping the Culture Around Concussion in Sports Get HEADS UP on Your Web Site Concussion ... HEADS UP on your web site! Create a culture of safety for young athletes Officials, learn how you can ... UP to Providers HEADS UP to Youth Sports HEADS UP to School Sports HEADS UP to ...

Connections: Superplasticity, Damascus Steels, Laminated Steels, and Carbon Dating

Science.gov (United States)

Wadsworth, Jeffrey

2016-12-01

In this paper, a description is given of the connections that evolved from the initial development of a family of superplastic plain carbon steels that came to be known as Ultra-High Carbon Steels (UHCS). It was observed that their very high carbon contents were similar, if not identical, to those of Damascus steels. There followed a series of attempts to rediscover how the famous patterns found on Damascus steels blades were formed. At the same time, in order to improve the toughness at room temperature of the newly-developed UHCS, laminated composites were made of alternating layers of UHCS and mild steel (and subsequently other steels and other metals). This led to a study of ancient laminated composites, the motives for their manufacture, and the plausibility of some of the claims relating to the number of layers in the final blades. One apparently ancient laminated composite, recovered in 1837 from the great pyramid of Giza which was constructed in about 2750 B.C., stimulated a carbon dating study of ancient steels. The modern interest in "Bladesmithing" has connections back to many of these ancient weapons.

Current status of stainless steel industry and development of stainless steel

International Nuclear Information System (INIS)

Lee, Yong Deuk; Lee, Chan Soo; Kim Kwang Tae

2000-01-01

Stainless steel is not only clean and smooth in its surface, but also it is superior in quality in terms of corrosion resistance and strength. So that, it is widely in use in the field of construction, chemical installations, and other industries. Growth of stainless steel industry started since the steel technology was developed for mass production in 1960s. Since then stainless steel industry grew rapidly on account of diversified development in this field and growth rate went up to 5.8% per year comparable to 2.3% of steel growth. The rapid growth is attributed to significant industry developments in Europe and Japan in the years of 1970s and 1980s. In addition to these the expansion of stainless steel industry in Korea and Taiwan. Presently Korea produces about 120,000 tons of stainless steel and occupies about 8% of international market. This means Korea become the second largest single country in world in stainless steel production. Moreover Korea is to reinforce its domestic production line by affiliating production companies, increasing of production capability, and specializing in types of stainless steel. This paper is to describe activity of material development, and types of stainless steel for industry use. (Hong, J. S.)

EXPERIMENTAL STUDIES ON THE QUASI-STATIC AXIAL CRUSHING BEHAVIOR OF FOAM-FILLED STEEL EXTRUSION TUBES

OpenAIRE

AL EMRAN ISMAIL

2010-01-01

The concerns of automotive safety have been given special attention in order to reduce human fatalities or injuries. One of the techniques to reduce collision impact or compression energy is by filling polymeric foam into metallic tubes. In this work, polyurethane foam was introduced into the steel extrusion tubes and quasi-statically compressed at constant cross-head displacement. Different tube thicknesses and foam densities were used and these parameters were related to the crashwor...

Z phase stability in AISI 316LN + Nb austenitic steels during creep at 650 C

Energy Technology Data Exchange (ETDEWEB)

Vodarek, Vlastimil [Technical Univ. Ostrava (Czech Republic)

2010-07-01

The creep resistance of austenitic CrNi(Mo) steels strongly depends on microstructural stability during creep exposure. Nitrogen additions to CrNi(Mo) austenitic steels can significantly improve the creep strength. One of the most successful methods of improving the long-term creep resistance of austenitic steels is based on increasing the extent of precipitation strengthening during creep exposure. The role of precipitates in the achievements of good creep properties has been extensively studied for a long time. Although many minor phases are now well documented there are still contractions and missing thermodynamic data about some minor phases. This contribution deals with results of microstructural studies on the minor phase evolution in wrought AISI 316LN niobium stabilised steels during long-term creep exposure at 650 C. Microstructural investigations were carried out on specimens taken from both heads and gauge lengths of ruptured test-pieces by means of optical metallography, transmission and scanning electron microscopy. The attention has been paid to evaluation of thermodynamic and dimensional stability of Z phase and other nitrogen bearing minor phases. Only two nitrogen-bearing minor phases formed in the casts investigated: Z phase and M{sub 6}X. The dimensional stability of Z phase particles was very high. (orig.)

[Factors influencing electrocardiogram results in workers exposed to noise in steel-making and steel-rolling workshops of an iron and steel plant].

Science.gov (United States)

Li, Y H; Yu, S F; Gu, G Z; Chen, G S; Zhou, W H; Wu, H; Jiao, J

2016-02-20

To investigate the factors influencing the electrocardiogram results in the workers exposed to noise in steel-making and steel rolling workshops of an iron and steel plant. From September to December, 2013, cluster sampling was used to select 3 150 workers exposed to noise in the steel-making and steel-rolling workshops of an iron and steel plant, and a questionnaire survey and physical examinations were performed. The number of valid workers was 2 915, consisting of 1 606 workers in the steel-rolling workshop and 1 309 in the steel-making workshop. The electrocardiogram results of the workers in steel-making and steel-rolling workshops were analyzed. The overall abnormal rate of electrocardiogram was 26.35%, and the workers in the steel-making workshop had a significantly higher abnormal rate of electrocardiogram than those in the steel-rolling workshop(32.24% vs 21.54%, Pelectrocardiogram than female workers(27.59% vs 18.61%, Pelectrocardiogram than those who did not drink(28.17% vs 23.75%, Pelectrocardiogram than those who were not exposed to high temperature(29.43% vs 20.14%, Pelectrocardiogram in the workers with cumulative noise exposure levels of electrocardiogram results. High cumulative noise exposure, alcohol consumption, and high temperature may affect the abnormal rate of electrocardiogram in the workers exposed to noise in steel-making and steel-rolling workshops.

Compactibility of atomized high-speed steel and steel 3 powders

International Nuclear Information System (INIS)

Kulak, L.D.; Gavrilenko, A.P.; Pikozh, A.P.; Kuz'menko, N.N.

1985-01-01

Spherical powders and powders of lammellar-scaly shape of high-speed R6M5K5 steel and steel 3 produced by the method of centrifugal atomization of a rotating billet under conditions of cold pressing in steel moulds are studied for thier compactability. Compacting pressure dependnences are establsihed for density of cold-pressed compacts of spherical and scaly powders. The powders of lammellar-scaly shape both of high-speed steel and steel 3 are found to possess better compactibility within a wide range of pressures as compared to powders of spherical shape. Compacts of the lammellar-scaly powders possess also higher mechanical strength

Sound transmission through lightweight double-leaf partitions: theoretical modelling

Science.gov (United States)

Wang, J.; Lu, T. J.; Woodhouse, J.; Langley, R. S.; Evans, J.

2005-09-01

This paper presents theoretical modelling of the sound transmission loss through double-leaf lightweight partitions stiffened with periodically placed studs. First, by assuming that the effect of the studs can be replaced with elastic springs uniformly distributed between the sheathing panels, a simple smeared model is established. Second, periodic structure theory is used to develop a more accurate model taking account of the discrete placing of the studs. Both models treat incident sound waves in the horizontal plane only, for simplicity. The predictions of the two models are compared, to reveal the physical mechanisms determining sound transmission. The smeared model predicts relatively simple behaviour, in which the only conspicuous features are associated with coincidence effects with the two types of structural wave allowed by the partition model, and internal resonances of the air between the panels. In the periodic model, many more features are evident, associated with the structure of pass- and stop-bands for structural waves in the partition. The models are used to explain the effects of incidence angle and of the various system parameters. The predictions are compared with existing test data for steel plates with wooden stiffeners, and good agreement is obtained.

Bond characteristics of steel fiber and deformed reinforcing steel bar embedded in steel fiber reinforced self-compacting concrete (SFRSCC)

Science.gov (United States)

Aslani, Farhad; Nejadi, Shami

2012-09-01

Steel fiber reinforced self-compacting concrete (SFRSCC) is a relatively new composite material which congregates the benefits of the self-compacting concrete (SCC) technology with the profits derived from the fiber addition to a brittle cementitious matrix. Steel fibers improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibers on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fiber and SCC firstly. Based on the available experimental results, the current analytical steel fiber pullout model (Dubey 1999) is modified by considering the different SCC properties and different fiber types (smooth, hooked) and inclination. In order to take into account the effect of fiber inclination in the pullout model, apparent shear strengths ( τ ( app)) and slip coefficient ( β) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle ( ϕ). Furthurmore, steel-concrete composite floors, reinforced concrete floors supported by columns or walls and floors on an elastic foundations belong to the category of structural elements in which the conventional steel reinforcement can be partially replaced by the use of steel fibers. When discussing deformation capacity of structural elements or civil engineering structures manufactured using SFRSCC, one must be able to describe thoroughly both the behavior of the concrete matrix reinforced with steel fibers and the interaction between this composite matrix and discrete steel reinforcement of the conventional type. However, even though the knowledge on bond behavior is essential for evaluating the overall behavior of structural components containing reinforcement and steel fibers

Corrosion resistant steel

International Nuclear Information System (INIS)

Zubchenko, A.S.; Borisov, V.P.; Latyshev, V.B.

1980-01-01

Corrosion resistant steel for production of sheets and tubes containing C, Mn, Cr, Si, Fe is suggested. It is alloyed with vanadium and cerium for improving tensile properties and ductility. The steel can be melted by a conventional method in electric-arc or induction furnaces. The mentioned steel is intended to be used as a substitute for nickel-bearing austenitic steels

The study of the corrosion protection of the low-carbon steel using film-products

International Nuclear Information System (INIS)

Aiancului, L.; Millet, Jean-Pierre

2001-01-01

The paper reports studies on the efficiency of the film-inhibitors that covered low-carbon steel placed in a humid medium, and also, the optimization of the working conditions to improve the resistance to corrosion. The analyzes were done in the Industrial Physical - Chemical Laboratories of INSA - Lyon by electrochemical stationary techniques. The experimental device was a potentiometer of type EGG PAR (Princeton Applied Research). It was connected with a computer and three potential electrodes introduced in a cell with NaCl 30 g/l solution to acquire the data and to process the information. The film-products used were organic hydrosoluble polymers with diphosphonic 'heads' that permit a very good absorption at the metallic surface. This research is used to protect the installations of low-carbon steel against the atmospheric and high temperature corrosion. (authors)

Generation of deposits and self ignited fires in H2S-H2O services (Paper No. 4.6)

International Nuclear Information System (INIS)

Agarwal, A.K.; Hiremath, S.C.

1992-01-01

The Heavy Water Plant (Kota) uses a large inventory of H 2 S gas at a nominal pressure and temperature. The plant has used mild steels/carbon steels as the material of construction of vessels, piping, flanges and fasteners. The entire construction is with flanged joints with raised face and spiral wound gaskets. Any leakages from any of the pipe line, flanged joints, heat exchanger covers, valve bonnets, valve glands etc causes H 2 S and H 2 O to leak out which generate deposits around the leakage paths after reaction with mild steel/carbon steels. The deposits grow into hard material, cause corrosion and thinning of stud bolts and gasket outer rings, weaken the confidence in the joint, and also cause ignited fires as they provide a source of ignition under certain conditions. (author). 2 refs

[Death caused by projectile guns--a retrospective analysis of 34 cases in Berlin and Hamburg].

Science.gov (United States)

Lignitz, E; Koops, E; Püschel, K

1988-01-01

The autopsy material of the institutes for forensic medicine in Berlin/GDR and Hamburg was analyzed retrospectively (period from 1961 till 1987; 70,000 autopsies) for fatalities caused by "humane killers" (n = 22) and stud guns (n = 12).-Epidemiological, criminological and morphological findings: The decreased were all men aged between 18 and 75 years (mean 48 years) except one 61 year-old paraplegic women who was killed by her husband with a humane killer. The great majority of cases consisted of suicides; two accidents at work were caused by stud guns. These unusual weapons are normally used by skilled people (i.e. butchers or constructional workers respectively). The fatal wounds were situated at the head, especially the forehead, seldom at the nape of the neck or in the mouth, or sometimes in the chest when using stud guns. Combined suicides (especially together with hanging) are not unusual. Survival periods (with or without acting capacity) can range between minutes or even months (after neurosurgical intervention).-The frequency of such unusual and overall rare cases did not raise during the investigation period.

The influence of aluminium, steel and polyurethane shoeing systems and of the unshod hoof on the injury risk of a horse kick. An ex vivo experimental study.

Science.gov (United States)

Sprick, Miriam; Fürst, Anton; Baschnagel, Fabio; Michel, Silvain; Piskoty, Gabor; Hartnack, Sonja; Jackson, Michelle A

2017-09-12

To evaluate the damage inflicted by an unshod hoof and by the various horseshoe materials (steel, aluminium and polyurethane) on the long bones of horses after a simulated kick. Sixty-four equine radii and tibiae were evaluated using a drop impact test setup. An impactor with a steel, aluminium, polyurethane, or hoof horn head was dropped onto prepared bones. An impactor velocity of 8 m/s was initially used with all four materials and then testing was repeated with a velocity of 12 m/s with the polyurethane and hoof horn heads. The impact process was analysed using a high-speed camera, and physical parameters, including peak contact force and impact duration, were calculated. At 8 m/s, the probability of a fracture was 75% for steel and 81% for aluminium, whereas polyurethane and hoof horn did not damage the bones. At 12 m/s, the probability of a fracture was 25% for polyurethane and 12.5% for hoof horn. The peak contact force and impact duration differed significantly between 'hard materials' (aluminium and steel) and 'soft materials' (polyurethane and hoof horn). The observed bone injuries were similar to those seen in analogous experimental studies carried out previously and comparable to clinical fracture cases suggesting that the simulated kick was realistic. The probability of fracture was significantly higher for steel and aluminium than for polyurethane and hoof horn, which suggests that the horseshoe material has a significant influence on the risk of injury for humans or horses kicked by a horse.

A multi-packer completion to measure hydraulic heads in a lightly fractured area in the Oxfordian limestone

International Nuclear Information System (INIS)

Scholz, E.; Cruchaudet, M.; Delay, J.; Piedevache, M.

2010-01-01

Document available in extended abstract form only. Andra has designed a new type of borehole completion in order to monitor simultaneously hydraulic heads. This completion is installed in a 420 m deep borehole drilled in the Oxfordian limestone formation. The borehole is located in the South-West of Andra's Underground Research Laboratory (URL) in a lightly fractured area. The multi-packer completion is built and installed by Solexperts. This device is composed of five measurement intervals isolated with rubber expandable packers and supported by stainless steel tubing. The packers are inflated with water at a pressure of 10 bars above the water pressure at that depth. Each measurement interval comprises an interval module embedding a pressure / temperature gauge connected to the interval through a filter. The gauges are connected through one cable to a data acquisition system on surface. This completion is removable. The packers can be deflated and the completion can be installed in another borehole. The packers are positioned in the EST461 borehole according to the caliper logging and the results of permeability tests. The hydraulic head measurements are compared with the local rainfall. Interval 1 (the deepest) shows a stable hydraulic head whereas intervals 2 to 5 show hydraulic head variations. The amplitude of the hydraulic head variations are closely related to the interval depth: the deepest the interval, the lowest the hydraulic head variation. Hydraulic heads in intervals 4 and 5 are similar. These intervals are probably connected. (authors)

Comparison between steel and lead shieldings for radiotherapy rooms regarding neutron doses to patients

International Nuclear Information System (INIS)

Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G.

2015-01-01

The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H *(10) n , within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5 x 5 cm 2 , 10 x 10 cm 2 , 20 x 20 cm 2 , 30 x 30 cm 2 and 40 x 40 cm 2 openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H *(10) n at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation. (author)

The steel scrap age.

Science.gov (United States)

Pauliuk, Stefan; Milford, Rachel L; Müller, Daniel B; Allwood, Julian M

2013-04-02

Steel production accounts for 25% of industrial carbon emissions. Long-term forecasts of steel demand and scrap supply are needed to develop strategies for how the steel industry could respond to industrialization and urbanization in the developing world while simultaneously reducing its environmental impact, and in particular, its carbon footprint. We developed a dynamic stock model to estimate future final demand for steel and the available scrap for 10 world regions. Based on evidence from developed countries, we assumed that per capita in-use stocks will saturate eventually. We determined the response of the entire steel cycle to stock saturation, in particular the future split between primary and secondary steel production. During the 21st century, steel demand may peak in the developed world, China, the Middle East, Latin America, and India. As China completes its industrialization, global primary steel production may peak between 2020 and 2030 and decline thereafter. We developed a capacity model to show how extensive trade of finished steel could prolong the lifetime of the Chinese steelmaking assets. Secondary steel production will more than double by 2050, and it may surpass primary production between 2050 and 2060: the late 21st century can become the steel scrap age.

Preparation and characterization of 304 stainless steel/Q235 carbon steel composite material

Directory of Open Access Journals (Sweden)

Wenning Shen

Full Text Available The composite material of 304 stainless steel reinforced Q235 carbon steel has been prepared by modified hot-rolling process. The resulted material was characterized by scanning electron microscope, three-electrode method, fault current impact method, electrochemical potentiodynamic polarization curve measurement and electrochemical impedance spectroscopy. The results showed that metallurgical bond between the stainless steel layer and carbon steel substrate has been formed. The composite material exhibited good electrical conductivity and thermal stability. The average grounding resistance of the composite material was about 13/20 of dip galvanized steel. There has no surface crack and bubbling formed after fault current impact. The composite material led to a significant decrease in the corrosion current density in soil solution, compared with that of hot dip galvanized steel and bare carbon steel. On the basis polarization curve and EIS analyses, it can be concluded that the composite material showed improved anti-corrosion property than hot-dip galvanized steel. Keywords: Stainless steel, Carbon steel, Anti-corrosion, Conductivity, Electrochemical, EIS

Process and device to set a separated helicoid thread in a large diameter tapped hole and use of this process and device

International Nuclear Information System (INIS)

Dworaczek, J.P.; Grypczynski, D.

1992-01-01

In a PWR reactor the vessel head is fixed to the reactor vessel by the vessel flange and closure studs. If the thread machined in the vessel flange is damaged or worn out, a separate thread, rolled up on a tapped drum is screwed in the tapped opening and the thread is fixed by a pin

Apparatus For Eddy-Current Inspection Of Bolts

Science.gov (United States)

Amos, Jay M.

1994-01-01

Eddy-current apparatus for inspection of bolts, studs, and other threaded fasteners detects flaws in threads, shanks, and head fillets. With help of apparatus, technician quickly inspects fasteners of various dimensions. Accommodates fasteners with diameters from 0.190 in. to 1 in. and with lengths up to 5 in. Basic design modified to accommodate fasteners of other sizes.

Computer-enhanced stereoscopic vision in a head-mounted operating binocular

International Nuclear Information System (INIS)

Birkfellner, Wolfgang; Figl, Michael; Matula, Christian; Hummel, Johann; Hanel, Rudolf; Imhof, Herwig; Wanschitz, Felix; Wagner, Arne; Watzinger, Franz; Bergmann, Helmar

2003-01-01

Based on the Varioscope, a commercially available head-mounted operating binocular, we have developed the Varioscope AR, a see through head-mounted display (HMD) for augmented reality visualization that seamlessly fits into the infrastructure of a surgical navigation system. We have assessed the extent to which stereoscopic visualization improves target localization in computer-aided surgery in a phantom study. In order to quantify the depth perception of a user aiming at a given target, we have designed a phantom simulating typical clinical situations in skull base surgery. Sixteen steel spheres were fixed at the base of a bony skull, and several typical craniotomies were applied. After having taken CT scans, the skull was filled with opaque jelly in order to simulate brain tissue. The positions of the spheres were registered using VISIT, a system for computer-aided surgical navigation. Then attempts were made to locate the steel spheres with a bayonet probe through the craniotomies using VISIT and the Varioscope AR as a stereoscopic display device. Localization of targets 4 mm in diameter using stereoscopic vision and additional visual cues indicating target proximity had a success rate (defined as a first-trial hit rate) of 87.5%. Using monoscopic vision and target proximity indication, the success rate was found to be 66.6%. Omission of visual hints on reaching a target yielded a success rate of 79.2% in the stereo case and 56.25% with monoscopic vision. Time requirements for localizing all 16 targets ranged from 7.5 min (stereo, with proximity cues) to 10 min (mono, without proximity cues). Navigation error is primarily governed by the accuracy of registration in the navigation system, whereas the HMD does not appear to influence localization significantly. We conclude that stereo vision is a valuable tool in augmented reality guided interventions. (note)

Plasma nitriding of steels

CERN Document Server

Aghajani, Hossein

2017-01-01

This book focuses on the effect of plasma nitriding on the properties of steels. Parameters of different grades of steels are considered, such as structural and constructional steels, stainless steels and tools steels. The reader will find within the text an introduction to nitriding treatment, the basis of plasma and its roll in nitriding. The authors also address the advantages and disadvantages of plasma nitriding in comparison with other nitriding methods. .

Steel

International Nuclear Information System (INIS)

Zorev, N.N.; Astafiev, A.A.; Loboda, A.S.; Savukov, V.P.; Runov, A.E.; Belov, V.A.; Sobolev, J.V.; Sobolev, V.V.; Pavlov, N.M.; Paton, B.E.

1977-01-01

Steels also containing Al, N and arsenic, are suitable for the construction of large components for high-power nuclear reactors due to their good mechanical properties such as good through-hardening, sufficiently low brittleness conversion temperature and slight displacement of the latter with neutron irradiation. Defined steels and their properties are described. (IHOE) [de

Tool steels

DEFF Research Database (Denmark)

Højerslev, C.

2001-01-01

On designing a tool steel, its composition and heat treatment parameters are chosen to provide a hardened and tempered martensitic matrix in which carbides are evenly distributed. In this condition the matrix has an optimum combination of hardness andtoughness, the primary carbides provide...... resistance against abrasive wear and secondary carbides (if any) increase the resistance against plastic deformation. Tool steels are alloyed with carbide forming elements (Typically: vanadium, tungsten, molybdenumand chromium) furthermore some steel types contains cobalt. Addition of alloying elements...... serves primarily two purpose (i) to improve the hardenabillity and (ii) to provide harder and thermally more stable carbides than cementite. Assuming proper heattreatment, the properties of a tool steel depends on the which alloying elements are added and their respective concentrations....

Creep deformation and rupture behavior of type 304/308 stainless steel structural weldments

International Nuclear Information System (INIS)

McAfee, W.J.; Richardson, M.; Sartory, W.K.

1977-01-01

The creep deformation and rupture of type 304/308 stainless steel structural weldments at 593 0 C (1100 0 F) was experimentally investigated to study the comparative behavior of the base metal and weld metal constituents. The tests were conducted in support of ORNL's program to develop high-temperature structural design methods applicable to liquid-metal fast breeder reactor (LMFBR) system components that operate in the creep range. The specimens used were thin-walled, right circular cylinders capped with either flat or hemispherical heads and tested under internal gas pressure. Circumferential welds were located in different regions of the cylinder or head and, with one exception, were geometrically duplicated by all base metal regions in companion specimens. Results are presented on the comparative deformation and rupture behavior of selected points in the base metal and weldment regions of the different specimens and on the overall surface strains for selected specimens

Substitution of modified 9 Cr-1 Mo steel for austentic stainless steels

International Nuclear Information System (INIS)

Sikka, V.K.

1982-04-01

This report describes the current program to develop a high-strength ferritic-martensitic steel. The alloy is essentially Fe-9% Cr-1% Mo with small additions of V and Nb and is known as modifed 9 Cr-1 Mo steel. Its elevated-temperature properties and design allowable stresses match those of type 304 stainless steel for temperatures up to 600 0 C and exceed those of other ferritic steels by factors of 2 to 3. The improved strength of this alloy permits its use in place of stainless steels for many applications

Weldability of Stainless Steels

International Nuclear Information System (INIS)

Saida, Kazuyoshi

2010-01-01

It gives an outline of metallographic properties of welding zone of stainless steels, generation and mechanisms of welding crack and decreasing of corrosion resistance of welding zone. It consists of seven chapters such as introduction, some kinds of stainless steels and properties, metallographic properties of welding zone, weld crack, toughness of welding zone, corrosion resistance and summary. The solidification modes of stainless steels, each solidification mode on the cross section of Fe-Cr-Ni alloy phase diagram, each solidification mode of weld stainless steels metal by electron beam welding, segregation state of alloy elements at each solidification mode, Schaeffler diagram, Delong diagram, effects of (P + S) mass content in % and Cr/Ni equivalent on solidification cracking of weld stainless steels metal, solidification crack susceptibility of weld high purity stainless steels metal, effects of trace impurity elements on solidification crack susceptibility of weld high purity stainless steels metal, ductile fracture susceptibility of weld austenitic stainless steels metal, effects of H2 and ferrite content on generation of crack of weld 25Cr-5N duplex stainless steels, effects of O and N content on toughness of weld SUS 447J1 metals, effect of ferrite content on aging toughness of weld austenitic stainless steel metal, corrosion morphology of welding zone of stainless steels, generation mechanism of knife line attack phenomenon, and corrosion potential of some kinds of metals in seawater at room temperature are illustrated. (S.Y.)

Research of formation of deposits in technological devices and corrosion of contact devices from stainless steel

Directory of Open Access Journals (Sweden)

KATAMANOV Vladimir Leonidovich

2017-11-01

Full Text Available The paper shows that for majority of technological plants used to process hydrocarbon raw materials when operating a problem of formation of deposits in still-head pipes after the rectifying and stabilization columns, furnaces and other technology devices in oil processing is still of great importance. The structure of still-head deposits of furnace coils and rectifying columns has been studied by the example of small technological plant (STP of JSC Kondensat (Aksay, the Republic of Kazakhstan. It was determined that key components of these deposits are sulfides of iron and copper as well as elementary sulfur. It is shown that the surface of contact devices of STP – grids made of stainless steel of brand 12X18H10T, is substantially subject to corrosion. These samples are the structures which are still keeping geometry of initial grids, but lost their functional properties and characteristics. When mechanical influence is applied such samples easily transform into gray high-disperse powder. During operation period of STP various corrosion inhibitors and deemulgators (for example, TAL-25-13-R have been tested. At the same time practically all tested brands of corrosion inhibitors couldn't decrease corrosion of stainless steel and formation of firm deposits in still-head pipes of technological devices. The existing corrosion inhibitors create protection on the boundary of phases metallic surface – liquid, but they aren't efficient on the boundary of phases metallic surface – liquid – steam-gas phase (at the temperature of 150–250оC. The authors propose the mechanism of formation of these compounds based on result of corrosion of metal gauzes made of stainless steels brand X6CrNiTi18-10in the presence of sulphurous compounds.An active method of corrosion prevention is recommended to apply. The method is based on creation of nanodimensional anticorrosion coatings from binary compounds (such as titanium nitride or pure metals (Ni, Cr, Ti

Preparation and characterization of 304 stainless steel/Q235 carbon steel composite material

Science.gov (United States)

Shen, Wenning; Feng, Lajun; Feng, Hui; Cao, Ying; Liu, Lei; Cao, Mo; Ge, Yanfeng

The composite material of 304 stainless steel reinforced Q235 carbon steel has been prepared by modified hot-rolling process. The resulted material was characterized by scanning electron microscope, three-electrode method, fault current impact method, electrochemical potentiodynamic polarization curve measurement and electrochemical impedance spectroscopy. The results showed that metallurgical bond between the stainless steel layer and carbon steel substrate has been formed. The composite material exhibited good electrical conductivity and thermal stability. The average grounding resistance of the composite material was about 13/20 of dip galvanized steel. There has no surface crack and bubbling formed after fault current impact. The composite material led to a significant decrease in the corrosion current density in soil solution, compared with that of hot dip galvanized steel and bare carbon steel. On the basis polarization curve and EIS analyses, it can be concluded that the composite material showed improved anti-corrosion property than hot-dip galvanized steel.

Compresibility and sinterability of HCx PM steel diluted with stainless steels

Directory of Open Access Journals (Sweden)

Elena Gordo

2003-12-01

Full Text Available HCx powder metallurgy steel contains in its composition high contents of Cr and C, and significant quantities of alloy elements typical of tool steels (Mo, V, W, to provide the corrosion resistance of stainless steel with wear resistance of tool steels. HCx appears to be a suitable material for applications in aggressive environments, as valve seat inserts in automotive engines. However, this steel presents a low compressibility leading to high production costs. In this work, some results carried out to improve the compressibility of HCx are presented. The way to attempt this improvement is the dilution of base material with two stainless steels, the ferritic 430LHC and the austenitic 316L. The powder mixes prepared were uniaxially pressed to study the compressibility. The sinterability was study by determining of density, hardness, transverse rupture strength (TRS and microstructural evolution after vacuum sintering at different temperatures. As a result, better compressibility is observed in the mixes although not all of them present the properties required.

Analysis of the SNR and sensing ability of different sensor types in a LIDAR system

Science.gov (United States)

Choi, Gyudong; Han, Munhyun; Seo, Hongseok; Mheen, Bongki

2017-10-01

LIDAR (light distance and ranging) systems use sensors to detect reflected signals. The performance of the sensors significantly affects the specification of the LIDAR system. Especially, the number and size of the sensors determine the FOV (field of view) and resolution of the system, regardless of which sensors are used. The resolution of an array-type sensor normally depends on the number of pixels in the array. In this type of sensor, there are several limitations to increase the number of pixels in an array for higher resolution, specifically complexity, cost, and size limitations. Another type of sensors uses multiple pairs of transmitter and receiver channels. Each channel detects different points with the corresponding directions indicated by the laser points of each channel. In this case, in order to increase the resolution, it is required to increase the number of channels, resulting in bigger sensor head size and deteriorated reliability due to heavy rotating head module containing all the pairs. In this paper, we present a method to overcome these limitations and improve the performance of the LIDAR system. ETRI developed a type of scanning LIDAR system called a STUD (static unitary detector) LIDAR system. It was developed to solve the problems associated with the aforementioned sensors. The STUD LIDAR system can use a variety of sensors without any limitations on the size or number of sensors, unlike other LIDAR systems. Since it provides optimal performance in terms of range and resolution, the detailed analysis was conducted in the STUD LIDAR system by applying different sensor type to have improved sensing performance.

Boron Steel: An Alternative for Costlier Nickel and Molybdenum Alloyed Steel for Transmission Gears

Directory of Open Access Journals (Sweden)

A. Verma

2010-06-01

Full Text Available Case Carburized (CC low carbon steels containing Ni, Cr and Mo alloying elements are widely used for transmission gears in automobile, as it possesses desired mechanical properties. In order to cut cost and save scarce materials like Ni and Mo for strategic applications, steel alloyed with Boron has been developed, which gives properties comparable to Ni-Cr-Mo alloyed steel. In the process of steel development, care was taken to ensure precipitation of boron which results in precipitation hardening. The characterization of the developed boron steel had exhibited properties comparable to Ni-Cr-Mo alloyed steel and superior to conventional boron steel.

Comparison between steel and lead shieldings for radiotherapy rooms regarding neutron doses to patients

Energy Technology Data Exchange (ETDEWEB)

Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G., E-mail: eng.cavaliere@gmail.com, E-mail: ggrprojetos@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Nuclear; Silva, A.X., E-mail: ademir@con.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil)

2015-07-01

The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H *(10){sub n}, within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5 x 5 cm{sup 2}, 10 x 10 cm{sup 2}, 20 x 20 cm{sup 2}, 30 x 30 cm{sup 2} and 40 x 40 cm{sup 2} openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H *(10){sub n} at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation. (author)

Kinematics of the AM-50 heading machine cutting head

Energy Technology Data Exchange (ETDEWEB)

Sikora, W; Bak, K; Klich, R [Politechnika Slaska, Gliwice (Poland). Instytut Mechanizacji Gornictwa

1987-01-01

Analyzes motion of the cutter head of the AM-50 heading machine. Two types of head motion are comparatively evaluated: planar motion and spatial motion. The spatial motion consists of the head rotational motion and horizontal or vertical feed motion, while planar motion consists of rotational motion and vertical feed motion. Equations that describe head motion under conditions of cutter vertical or horizontal feed motion are derived. The angle between the cutting speed direction and working speed direction is defined. On the basis of these formulae variations of cutting speed depending on the cutting tool position on a cutter head are calculated. Calculations made for 2 extreme cutting tools show that the cutting speed ranges from 1,205 m/s to 3,512 m/s. 4 refs.

Interaction model of steel ladle of continuous caster in steel works

Directory of Open Access Journals (Sweden)

Huang Bang Fu

2016-01-01

Full Text Available For further research on the precondition and interoperability model of interaction ladles among continuous caster, this article takes steel ladle of Y steel works as the object of research. On the basis of turnover number calculation model of single cast steel ladle, the relationship between cast number and the turnover number and turnover times and last turnover number are further analyzed. The simulation of steel ladle turnover rules was taken on the 2 continuous casters with Gantt chart. After that, the relationships between turnover number and last turnover number and non-turnover number are researched deeply. Combining with the Gantt chart, the expressions of start casting time and empty ladle ending time and heavy ladle starting time were put forward. The precondition of steel ladle interaction is obtained, which means the exchange ladle should not undertaking transport task in first stop continuous caster, and the empty ladle end time of exchange ladle of first stop continuous caster should early than the heavy ladle start time of last stop continuous caster. After applying the model to practice, 3 steel ladles of No.2 continuous caster can be reduced. This research results is supplying theoretical basis for steel ladle controlling and production organization optimization, and enriches the theory and method of metallurgical process integration.

Age-hardening susceptibility of high-Cr ODS ferritic steels and SUS430 ferritic steel

Energy Technology Data Exchange (ETDEWEB)

Chen, Dongsheng, E-mail: chen.dongsheng85@gmail.com [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Kimura, Akihiko; Han, Wentuo; Je, Hwanil [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

2015-10-15

Highlights: • The role of oxide particles in α/α′ phase decomposition behavior; microstructure of phase decomposition observed by TEM. • The characteristics of ductility loss caused by age-hardening. • Correlation of phase decomposition and age-hardening explained by dispersion strengthened models. • Age-hardening susceptibility of ODS steels and SUS430 steel. - Abstract: The effect of aging on high-Cr ferritic steels was investigated with focusing on the role of oxide particles in α/α′ phase decomposition behavior. 12Cr-oxide dispersion strengthened (ODS) steel, 15Cr-ODS steel and commercial SUS430 steel were isothermally aged at 475 °C for up to 10,000 h. Thermal aging caused a larger hardening in SUS430 than 15Cr-ODS, while 12Cr-ODS showed almost no hardening. A characteristic of the ODS steels is that the hardening was not accompanied by the significant loss of ductility that was observed in SUS430 steel. After aging for 2000 h, SUS430 steel shows a larger ductile–brittle transition temperature (DBTT) shift than 15Cr-ODS steel, which suggests that the age-hardening susceptibility is lower in 15Cr-ODS steel than in conventional SUS430 steel. Thermal aging leaded to a large number of Cr-rich α′ precipitates, which were confirmed by transmission electron microscopy (TEM). Correlation of age-hardening and phase decomposition was interpreted by Orowan type strengthening model. Results indicate that oxide particles cannot only suppress ductility loss, but also may influence α/α′ phase decomposition kinetics.

Mechanical behavior and fracture characterization of the T91 martensitic steel in liquid sodium environment

International Nuclear Information System (INIS)

Hamdane, Ouadie

2012-01-01

The T91 martensitic steel is designed to constitute structural material of future sodium fast reactors of fourth generation, where it will be subjected to stresses in presence of liquid sodium. This study presents a qualitative and quantitative estimate of the sensitivity of T91 steel towards the phenomenon of liquid metal embrittlement. The effect of liquid sodium on T91 steel was studied and quantified according to the temperature and the cross head rate displacement, by using a set-up of Small Punch Test, three and four bending test, developed in laboratory. Mechanical tests in sodium environment are carried out inside a Plexiglas cell, conceived and developed at the laboratory. The atmosphere inside this cell is severely purified and controlled, in order to avoid on the one hand an explosive reaction of sodium with moisture, or an ignition with oxygen, and on the other hand to minimize the presence of impurities in liquid sodium used. The presence of sodium accelerates T91 steel fracture at low temperature, without modifying its ductile character. The T91 pre-immersion in sodium makes it possible to dissolve the protective layer of chromium oxide, and to obtain an intimate contact with the molten metal. However, pre-immersion generates a surface defects which cause a partial embrittlement by sodium. The hardening of T91 steel by heat treatment with a tempering temperature of 550 C (T91-TR550) causes a total embrittlement of steel in presence of sodium, with and without pre-immersion. The rupture of the T91-TR550 steel takes then place by intergranular de-cohesion, corresponding to the crack initiation phase, followed by laths de-cohesion, corresponding to the phase of propagation of these cracks. The mechanism suggested in this study is based on the intergranular penetration of sodium, supported by the presence of segregated impurities such phosphorus, and by the plastic deformation [fr

Redemption of asthma pharmaceuticals among stainless steel and mild steel welders

DEFF Research Database (Denmark)

Kristiansen, Pernille; Jørgensen, Kristian Tore; Hansen, Johnni

2015-01-01

PURPOSE: The purpose was to examine bronchial asthma according to cumulative exposure to fume particulates conferred by stainless steel and mild steel welding through a proxy of redeemed prescribed asthma pharmaceuticals. METHODS: A Danish national company-based historical cohort of 5,303 male ever...... was estimated by combining questionnaire data on welding work with a welding exposure matrix. The estimated exposure accounted for calendar time, welding intermittence, type of steel, welding methods, local exhaustion and welding in confined spaces. Hazard ratios (HRs) with 95 % confidence intervals (CIs) were...... nonsignificant increased rate of redemption of asthma medicine was observed among high-level exposed stainless steel welders in comparison with low-level exposed welders (HR 1.54, 95 % CI 0.76-3.13). This risk increase was driven by an increase risk among non-smoking stainless steel welders (HR 1.46, 95 % CI 1...

Effects of simulated inflammation on the corrosion of 316L stainless steel

Energy Technology Data Exchange (ETDEWEB)

Brooks, Emily K.; Brooks, Richard P. [Department of Biomedical Engineering, State University of New York at Buffalo (United States); Ehrensberger, Mark T., E-mail: mte@buffalo.edu [Department of Biomedical Engineering, State University of New York at Buffalo (United States); Department of Orthopaedics, State University of New York at Buffalo (United States)

2017-02-01

Stainless steel alloys, including 316L, find use in orthopaedics, commonly as fracture fixation devices. Invasive procedures involved in the placement of these devices will provoke a local inflammatory response that produces hydrogen peroxide (H{sub 2}O{sub 2}) and an acidic environment surrounding the implant. This study assessed the influence of a simulated inflammatory response on the corrosion of 316L stainless steel. Samples were immersed in an electrolyte representing either normal or inflammatory physiological conditions. After 24 h of exposure, electrochemical impedance spectroscopy (EIS) and inductively coupled plasma mass spectroscopy (ICPMS) were used to evaluate differences in corrosion behavior and ion release induced by the inflammatory conditions. Scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX) were used to evaluate surface morphology and corrosion products formed on the sample surface. Inflammatory conditions, involving the presence of H{sub 2}O{sub 2} and an acidic pH, significantly alter the corrosion processes of 316L stainless steel, promoting aggressive and localized corrosion. It is demonstrated that particular consideration should be given to 316L stainless steel implants with crevice susceptible areas (ex. screw-head/plate interface), as those areas may have an increased probability of rapid and aggressive corrosion when exposed to inflammatory conditions. - Highlights: • The corrosion of 316L exposed to simulated inflammation is examined. • Inflammation is replicated with an acidic electrolyte containing hydrogen peroxide. • Inflammatory conditions increase 316L corrosion compared to normal conditions. • Accelerated corrosion under inflammation is likely due to crevice corrosion. • Care should be taken using 316L in devices with crevice susceptible areas.

Design of steel-liners and their anchorage with regard to non-linear behaviour of liner-material and anchorage

International Nuclear Information System (INIS)

Oberpichler, R.

1979-01-01

The thin steel liner attached by studs or rib-type anchors to the interior wall of a Prestressed Concrete Reactor Pressure Vessel (PCRV) or a Concrete Containment Vessel (PCCV) has to provide the leak-tightness of the vessel. The liner also may serve as internal shuttering for placing concrete as well as a support for the cooling system or thermal isolation. Mainly strained by self-limited loads imposed on the liner by deformations of the vessel-wall or by heatup inside the vessel the liner predominantly will function in a compressive biaxially strained state like a membrane. The vessel-wall is assumed to be a rigid boundary without reactions caused by the liner-anchor-restraints. Furthermore it is assumed that the liner supported in a close-spaced pattern to the concrete with respect to self-limited loads and all effects of non-linear behaviour of liner-material and non-linear anchor-characteristics will not fail by instability, especially not by an effect of snapthrough. Only one essential mode of failure, the shear connector failure is assumed to be basis for all liner investigations. Design of the liner and its anchorage therefore is based on the analysis of large deformations with regard to elastic-plastic behaviour of liner-material and non-linear anchor characteristics. By this method both economical and safe sizing and spacing of the anchors can be calculated. (orig.)

Nitrogen-alloyed martensitic steels

International Nuclear Information System (INIS)

Berns, H.

1988-01-01

A report is presented on initial results with pressure-nitrided martensitic steels. In heat-resistant steels, thermal stability and toughness are raised by nitrogen. In cold work steel, there is a more favourable corrosion behaviour. (orig./MM) [de

MICROALLOYED STEELS FOR THE AUTOMOTIVE INDUSTRY

Directory of Open Access Journals (Sweden)

Debanshu Bhattacharya

2014-12-01

Full Text Available Two major drivers for the use of newer steels in the automotive industry are fuel efficiency and increased safety performance. Fuel efficiency is mainly a function of weight of steel parts, which in turn, is controlled by gauge and design. Safety is determined by the energy absorbing capacity of the steel used to make the part. All of these factors are incentives for the U.S. automakers to use both Highly Formable and Advanced High Strength Steels (AHSS to replace the conventional steels used to manufacture automotive parts in the past. AHSS is a general term used to describe various families of steels. The most common AHSS is the dual-phase steel that consists of a ferrite-martensite microstructure. These steels are characterized by high strength, good ductility, low tensile to yield strength ratio and high bake hardenability. Another class of AHSS is the complex-phase or multi-phase steel which has a complex microstructure consisting of various phase constituents and a high yield to tensile strength ratio. Transformation Induced Plasticity (TRIP steels is another class of AHSS steels finding interest among the U.S. automakers. These steels consist of a ferrite-bainite microstructure with significant amount of retained austenite phase and show the highest combination of strength and elongation, so far, among the AHSS in use. High level of energy absorbing capacity combined with a sustained level of high n value up to the limit of uniform elongation as well as high bake hardenability make these steels particularly attractive for safety critical parts and parts needing complex forming. A relatively new class of AHSS is the Quenching and Partitioning (Q&P steels. These steels seem to offer higher ductility than the dual-phase steels of similar strengths or similar ductility as the TRIP steels at higher strengths. Finally, martensitic steels with very high strengths are also in use for certain parts. The most recent initiative in the area of AHSS

Notch aspects of RSP steel microstructure

Directory of Open Access Journals (Sweden)

Michal Černý

2012-01-01

Full Text Available For a rather long time, basic research projects have been focused on examinations of mechanical properties for Rapid Solidification Powder (RSP steels. These state-of-art steels are commonly known as “powdered steels“. In fact, they combine distinctive attributes of conventional steel alloys with unusual resistance of construction material manufactured by so called “pseudo-powdered” metallurgy.Choice of suitable materials for experimental verification was carried out based on characteristic application of so called “modern steel”. First, groups of stainless and tool steel types (steel grades ČSN 17 and 19 were selected. These provided representative specimens for the actual comparison experiment. For stainless steel type, two steel types were chosen: hardenable X47Cr14 (ČSN 17 029 stainless steel and non-hardenable X2CrNiMo18-14-3 (ČSN 17 350 steel. They are suitable e.g. for surgical tools and replacements (respectively. For tooling materials, C80U (ČSN 19 152 carbon steel and American D2 highly-alloyed steel (ČSN “equivalent” being 19 572 steel were chosen for the project. Finally, the M390 Böhler steel was chosen as representative of powdered (atomized steels. The goal of this paper is to discuss structural aspects of modern stainless and tool steel types and to compare them against the steel made by the RSP method. Based on the paper's results, impact of powdered steel structural characteristics on the resistance to crack initiation shall be evaluated.

FEM-calculation of different creep-tests with French and German RPV-steels

International Nuclear Information System (INIS)

Willschuetz, H.-G.; Altstadt, E.; Weiss, F.-P.; Sehgal, B.R.

2003-01-01

For calculations of Lower Head Failure experiments like FOREVER it is necessary to model creep and plasticity processes. Therefore a Finite Element Model is developed using a numerical approach which avoids the use of a single creep law employing constants derived from the data for a limited stress and temperature range. Instead of this a numerical creep data base (CDB) is developed where the creep strain rate is evaluated in dependence on the current total strain, temperature and equivalent stress. A main task for this approach is the generation and validation of the CDB. For an evaluation of the failure times a damage model according to an approach of Lemaitre is applied. The validation of the numerical model is performed by the simulation of and comparison with experiments. This is done in 3 levels: starting with the simulation of single uniaxial creep tests, which is considered as a 1D-problem. In the next level so called 'tube-failure-experiments' are modeled: the RUPTHER-14 and the 'MPA-Meppen'- experiment. These experiments are considered as 2D-problems. Finally the numerical model is applied to scaled 3D experiments, where the lower head of a PWR is represented in its hemispherical shape, like in the FOREVER experiments. An interesting question to be solved in this frame is the comparability of the French 16MND5 and the German 20MnMoNi55 RPV-steels, which are chemically nearly identical. If these 2 steels show a similar behavior, it should be allowed to transfer experimental and numerical data from one to the other. (author)

Field monitoring of rail squats using 3D ultrasonic mapping technique

International Nuclear Information System (INIS)

Kaewunruen, S.; Ishida, M.

2014-01-01

Rail squats and studs are typically classified as the propagation of any cracks .that have grown longitudinally through the subsurface. Some of the cracks could propagate to the bottom of rails transversely, which have branched from the initial longitudinal cracks with a depression of rail surface. The rail defects are commonly referred to as 'squats' when they were initiated from a damage layer caused by rolling contact fatigue, and as 'studs' when they were associated with a white etching layer caused by the transformation from pearlitic steel due to friction heat generated by wheel sliding or excessive traction. Such above-mentioned rail defects have been often observed in railway tracks catered for either light passenger or heavy freight traffics and for low, medium or high speed trains all over the world for over 60 years except some places such as sharp curves where large wear takes place under severe friction between the wheel flange and rail gauge face. It becomes a much-more significant issue when the crack grows and sometimes flakes off the rail (by itself or by insufficient rail grinding), resulting in a rail surface irregularity. Such rail surface defects induce wheel/rail impact and large amplitude vibration of track structure and poor ride quality. In Australia, Europe, and Japan, rail squats/studs have occasionally turned into broken rails. The root cause and preventive solution to this defect are still under investigation from the fracture mechanics and material sciences point of view. Some patterns of squat/stud development related to both curve and tangent track geometries have been observed and squat growth has been monitored for individual squats using ultrasonic mapping techniques. This paper highlights the field monitoring of squat/stud distribution and its growth. Squat/stud growth has been detected and scanned using the ultrasonic measurement device on a grid applied to the rail surface. The depths of crack paths at each grid node form a

Field monitoring of rail squats using 3D ultrasonic mapping technique

Energy Technology Data Exchange (ETDEWEB)

Kaewunruen, S., E-mail: sakdirat.kaewunruen@transport.nsw.gov.au [NSW, Transport, Sydney (Australia); Ishida, M., E-mail: ishida-mk@n-koei.jp [Nippon Koei Co. Ltd., Railway Div., Railway Engineering Dept., Chiyoda-ku, Tokyo (Japan)

2014-11-15

Rail squats and studs are typically classified as the propagation of any cracks .that have grown longitudinally through the subsurface. Some of the cracks could propagate to the bottom of rails transversely, which have branched from the initial longitudinal cracks with a depression of rail surface. The rail defects are commonly referred to as 'squats' when they were initiated from a damage layer caused by rolling contact fatigue, and as 'studs' when they were associated with a white etching layer caused by the transformation from pearlitic steel due to friction heat generated by wheel sliding or excessive traction. Such above-mentioned rail defects have been often observed in railway tracks catered for either light passenger or heavy freight traffics and for low, medium or high speed trains all over the world for over 60 years except some places such as sharp curves where large wear takes place under severe friction between the wheel flange and rail gauge face. It becomes a much-more significant issue when the crack grows and sometimes flakes off the rail (by itself or by insufficient rail grinding), resulting in a rail surface irregularity. Such rail surface defects induce wheel/rail impact and large amplitude vibration of track structure and poor ride quality. In Australia, Europe, and Japan, rail squats/studs have occasionally turned into broken rails. The root cause and preventive solution to this defect are still under investigation from the fracture mechanics and material sciences point of view. Some patterns of squat/stud development related to both curve and tangent track geometries have been observed and squat growth has been monitored for individual squats using ultrasonic mapping techniques. This paper highlights the field monitoring of squat/stud distribution and its growth. Squat/stud growth has been detected and scanned using the ultrasonic measurement device on a grid applied to the rail surface. The depths of crack paths at each

Steel-reinforced concrete-filled steel tubular columns under axial and lateral cyclic loading

Science.gov (United States)

Farajpourbonab, Ebrahim; Kute, Sunil Y.; Inamdar, Vilas M.

2018-03-01

SRCFT columns are formed by inserting a steel section into a concrete-filled steel tube. These types of columns are named steel-reinforced concrete-filled steel tubular (SRCFT) columns. The current study aims at investigating the various types of reinforcing steel section to improve the strength and hysteresis behavior of SRCFT columns under axial and lateral cyclic loading. To attain this objective, a numerical study has been conducted on a series of composite columns. First, FEM procedure has been verified by the use of available experimental studies. Next, eight composite columns having different types of cross sections were analyzed. For comparison purpose, the base model was a CFT column used as a benchmark specimen. Nevertheless, the other specimens were SRCFT types. The results indicate that reinforcement of a CFT column through this method leads to enhancement in load-carrying capacity, enhancement in lateral drift ratio, ductility, preventing of local buckling in steel shell, and enhancement in energy absorption capacity. Under cyclic displacement history, it was observed that the use of cross-shaped reinforcing steel section causes a higher level of energy dissipation and the moment of inertia of the reinforcing steel sections was found to be the most significant parameter affecting the hysteresis behavior of SRCFT columns.

Gender differences in head-neck segment dynamic stabilization during head acceleration.

Science.gov (United States)

Tierney, Ryan T; Sitler, Michael R; Swanik, C Buz; Swanik, Kathleen A; Higgins, Michael; Torg, Joseph

2005-02-01

Recent epidemiological research has revealed that gender differences exist in concussion incidence but no study has investigated why females may be at greater risk of concussion. Our purpose was to determine whether gender differences existed in head-neck segment kinematic and neuromuscular control variables responses to an external force application with and without neck muscle preactivation. Forty (20 females and 20 males) physically active volunteers participated in the study. The independent variables were gender, force application (known vs unknown), and force direction (forced flexion vs forced extension). The dependent variables were kinematic and EMG variables, head-neck segment stiffness, and head-neck segment flexor and extensor isometric strength. Statistical analyses consisted of multiple multivariate and univariate analyses of variance, follow-up univariate analyses of variance, and t-tests (P Gender differences existed in head-neck segment dynamic stabilization during head angular acceleration. Females exhibited significantly greater head-neck segment peak angular acceleration (50%) and displacement (39%) than males despite initiating muscle activity significantly earlier (SCM only) and using a greater percentage of their maximum head-neck segment muscle activity (79% peak activity and 117% muscle activity area). The head-neck segment angular acceleration differences may be because females exhibited significantly less isometric strength (49%), neck girth (30%), and head mass (43%), resulting in lower levels of head-neck segment stiffness (29%). For our subject demographic, the results revealed gender differences in head-neck segment dynamic stabilization during head acceleration in response to an external force application. Females exhibited significantly greater head-neck segment peak angular acceleration and displacement than males despite initiating muscle activity earlier (SCM only) and using a greater percentage of their maximum head-neck segment

Structural amorphous steels

International Nuclear Information System (INIS)

Lu, Z.P.; Liu, C.T.; Porter, W.D.; Thompson, J.R.

2004-01-01

Recent advancement in bulk metallic glasses, whose properties are usually superior to their crystalline counterparts, has stimulated great interest in fabricating bulk amorphous steels. While a great deal of effort has been devoted to this field, the fabrication of structural amorphous steels with large cross sections has remained an alchemist's dream because of the limited glass-forming ability (GFA) of these materials. Here we report the discovery of structural amorphous steels that can be cast into glasses with large cross-section sizes using conventional drop-casting methods. These new steels showed interesting physical, magnetic, and mechanical properties, along with high thermal stability. The underlying mechanisms for the superior GFA of these materials are discussed

Prospects of structural steels

International Nuclear Information System (INIS)

Bannykh, O.A.

2012-01-01

The current state of world steel production is considered as well as the development strategy of metallurgy industry in the Russian Federation through to 2020. The main factors determining the conservation of steel as perspective material for industry are given: energy expenses on production, the well-proven recirculation technology, the capability of changing steel properties in wide range, temperature range of operation. The conclusion is made that in the immediate future steel will not lose its importance [ru

Mechanical properties and fatigue strength of high manganese non-magnetic steel/carbon steel welded joints

International Nuclear Information System (INIS)

Nakaji, Eiji; Ikeda, Soichi; Kim, You-Chul; Nakatsuji, Yoshihiro; Horikawa, Kosuke.

1997-01-01

The dissimilar materials welded joints of high manganese non-magnetic steel/carbon steel (hereafter referred to as DMW joints), in which weld defects such as hot crack or blowhole are not found, were the good quality. Tensile strength of DMW joints was 10% higher than that of the base metal of carbon steel. In the bend tests, the DMW joints showed the good ductility without crack. Charpy absorbed energy at 0(degC) of the DMW joints was over 120(J) in the bond where it seems to be the lowest. Large hardening or softening was not detected in the heat affected zone. Fatigue strength of the DMW joints is almost the same with that of the welded joints of carbon steel/carbon steel. As the fatigue strength of the DMW joints exceeds the fatigue design standard curve of JSSC for carbon steel welded joints, the DMW joints can be treated the same as the welded joints of carbon steel/carbon steel of which strength is lower than that of high manganese non-magnetic steel, from the viewpoint of the fatigue design. (author)

Damascus steel ledeburite class

Science.gov (United States)

Sukhanov, D. A.; Arkhangelsky, L. B.; Plotnikova, N. V.

2017-02-01

Discovered that some of blades Damascus steel has an unusual nature of origin of the excess cementite, which different from the redundant phases of secondary cementite, cementite of ledeburite and primary cementite in iron-carbon alloys. It is revealed that the morphological features of separate particles of cementite in Damascus steels lies in the abnormal size of excess carbides having the shape of irregular prisms. Considered three hypotheses for the formation of excess cementite in the form of faceted prismatic of excess carbides. The first hypothesis is based on thermal fission of cementite of a few isolated grains. The second hypothesis is based on the process of fragmentation cementite during deformation to the separate the pieces. The third hypothesis is based on the transformation of metastable cementite in the stable of angular eutectic carbide. It is shown that the angular carbides are formed within the original metastable colony ledeburite, so they are called “eutectic carbide”. It is established that high-purity white cast iron is converted into of Damascus steel during isothermal soaking at the annealing. It was revealed that some of blades Damascus steel ledeburite class do not contain in its microstructure of crushed ledeburite. It is shown that the pattern of carbide heterogeneity of Damascus steel consists entirely of angular eutectic carbides. Believe that Damascus steel refers to non-heat-resistant steel of ledeburite class, which have similar structural characteristics with semi-heat-resistant die steel or heat-resistant high speed steel, differing from them only in the nature of excess carbide phase.

Micro-Abrasion Wear Resistance of Borided 316L Stainless Steel and AISI 1018 Steel

Science.gov (United States)

Reséndiz-Calderon, C. D.; Rodríguez-Castro, G. A.; Meneses-Amador, A.; Campos-Silva, I. E.; Andraca-Adame, J.; Palomar-Pardavé, M. E.; Gallardo-Hernández, E. A.

2017-11-01

The 316L stainless steel has high corrosion resistance but low tribological performance. In different industrial sectors (biomedical, chemical, petrochemical, and nuclear engineering), improvement upon wear resistance of 316L stainless steel components using accessible and inexpensive methods is critical. The AISI 1018 steel is widely used in industry, but its tribological performance is not the best among steels. Therefore, in this study the behavior of the borided 316L stainless steel and 1018 steel is evaluated under micro-abrasion wear. The boriding was carried out at 1223 K over 6 h of exposure time, resulting in a biphase layer composed of FeB/Fe2B phases. In order to evaluate Fe2B phase with no influence from FeB phase, AISI 1018 steel samples were borided at 1273 K for over 20 min and then diffusion annealed at 1273 K over 2 h to obtain a Fe2B mono-phase layer. Micro-abrasion wear resistance was evaluated by a commercial micro-abrasion testing rig using a mix of F-1200 SiC particles with deionized water as abrasive slurry. The obtained wear rates for FeB and Fe2B phases and for the 316L stainless steel were compared. Wear resistance of 316L stainless steel increases after boriding. The wear mechanisms for both phases and for the stainless steel were identified. Also, transient conditions for rolling and grooving abrasion were determined for the FeB and Fe2B phases.

Behaviour of partially composite precast concrete sandwich panels under flexural and axial loads

Science.gov (United States)

Tomlinson, Douglas George

Precast concrete sandwich panels are commonly used on building exteriors. They are typically composed of two concrete wythes that surround rigid insulation. They are advantageous as they provide both structural and thermal resistance. The structural response of sandwich panels is heavily influenced by shear connectors that link the wythes together. This thesis presents a study on partially composite non-prestressed precast concrete wall panels. Nine flexure tests were conducted on a wall design incorporating 'floating' concrete studs and Glass Fibre Reinforced Polymer (GFRP) connectors. The studs encapsulate and stiffen the connectors, reducing shear deformations. Ultimate loads increased from 58 to 80% that of a composite section as the connectors' reinforcement ratio increased from 2.6 to 9.8%. This design was optimized by reinforcing the studs and integrating them with the structural wythe; new connectors composed of angled steel or Basalt-FRP (BFRP) were used. The load-slip response of the new connector design was studied through 38 double shear push-through tests using various connector diameters and insertion angles. Larger connectors were stronger but more likely to pull out. Seven flexure tests were conducted on the new wall design reinforced with different combinations of steel and BFRP connectors and reinforcement. Composite action varied from 50 to 90% depending on connector and reinforcement material. Following this study, the axial-bending interaction curves were established for the new wall design using both BFRP and steel connectors and reinforcement. Eight panels were axially loaded to predesignated loads then loaded in flexure to failure. A technique is presented to experimentally determine the effective centroid of partially composite sections. Beyond the tension and compression-controlled failure regions of the interaction curve, a third region was observed in between, governed by connector failure. Theoretical models were developed for the bond

Stahlschüssel key to steel

CERN Document Server

Wegst, W S

2016-01-01

The Key to Steel (Stahlschlüssel/Stahlschluessel) cross reference book will help you to decode / decipher steel designations and find equivalent materials worldwide. The 2016 edition includes more than 70,000 standard designations and trade names from approximately 300 steelmakers and suppliers. Presentation is trilingual: English, French, and German. Materials covered include structural steels, tool steels, valve steels, high temperature steels and alloys, stainless and heat-resisting steels, and more. Standards and designations from 25 countries are cross-referenced.

Methods of forging steel

OpenAIRE

Pečoler, Primož

2014-01-01

The following work presents processes of steel forming, challenges when forging steel, forming machines suitable for forging and which choice of machine is most suitable for forging. We can separate steel forming to free forging and drop forging. Free forging can be divided to hand forging and machine forging. The correct choice of furnaces is also very important. We must reach correct temperature in the furnace for raw steel to melt with less scalings. In diploma I mentioned some machine...

Evolution of umbilicals in Brazil: optimizing deepwater umbilical applications with thermoplastic hoses and steel tubes

Energy Technology Data Exchange (ETDEWEB)

Guerra Neto, Mauro Del [DuPont do Brasil S.A., Barueri, SP (Brazil)

2008-07-01

Subsea umbilicals in the past 25 years have evolved in parallel with other subsea oil and gas technologies, as the search for hydrocarbons needed to drive the global economy has led offshore exploration and development companies to seek reserves ever-farther from shore in water thousands of meters deep. Relegated to little more than afterthought status before the push into deep water, modern umbilicals have now become crucial components linking deep water producers to their subsea wells, controlling subsea production systems through hydraulic and electrical power and injecting production chemicals for corrosion-, scale-, and hydrate-inhibition at subsea well heads. Particularly in subsea developments involving several deep water wells, umbilicals today are integral to both the production-system design and the chosen operating strategy. Failure of an umbilical linking a subsea well head in deep water to a host production facility can inflict severe economic consequences upon an operator by impairing production operations or halting production altogether. The additional cost of repairing or replacing a failed umbilical can run into the millions of dollars. As offshore oil and gas production has moved into ever-deeper water, umbilical manufacturers have begun introducing new stronger materials to handle the inherently higher pressures and temperatures. Today, two types of construction are used for fluid conduits in umbilical systems deployed in deep water: thermoplastic hoses and steel tubes. Steel tubes are generally more expensive than thermoplastic hoses, relatively stiff and considered to have high tensile strength, while thermoplastic hoses are extremely flexible and exhibit lower tensile strength. This lower tensile strength of the hoses may be compensated by including steel wire armoring in the umbilical. This also provides the added benefits of additional mechanical protection compared with the equivalent unarmored steel-tubes umbilicals. When either

Corrosion characteristics of DMR-1700 steel and comparison with different steels in marine environment

International Nuclear Information System (INIS)

Gurrappa, I.; Malakondaiah, G.

2005-01-01

In the present paper, a systematic corrosion study has been carried out on DMR-1700 steel to understand the protective nature of oxide scale that forms on its surface under marine environmental conditions. Further, the studies related to oxide scales as well as pitting and crevice corrosion resistance of both stainless steels and widely used low alloy steel EN24 in marine environment have been studied for comparison purpose. The surface morphologies of corroded steels have been observed under scanning electron microscope (SEM) in order to understand the nature of corrosion. A high performance protective coating that has been developed for protection of low alloy steels DMR-1700 and EN24 against corrosion is presented after stressing the importance of surface engineering in enhancing the life of steels. Based on the studies with different techniques, DMR-1700 steel has been recommended for manufacture of components used in aerospace systems in association with appropriate protective coating for improving their efficiency

Feasibility studies on design of steel containment for AHWR subjected to normal and seismic loads

International Nuclear Information System (INIS)

Verma, Rajeev; Reddy, G.R.; Vaze, K.K.; Kumar, Ajay

2011-01-01

Reactor Containments in nuclear power plants are the final leak tight harriers preventing release of radioactive material during the accident to the environment. It should provide containment against fission product release, passive containment cooling and should be economical. In the world various configurations have been adopted depending on the accident pressures, temperatures, leak rate requirements and radius of exclusion zones. economy, speed of construction etc. Some of the containments arc of Reinforced Cement Concrete (RCC), Prestressed Cement Concrete (PCC), RCC with the liner, PCC with the liner and Steel. The design concepts and the choice of containment depend on the country practices. The main objective of this paper is to design, analyze and characterize the effectiveness of steel containment for AHWR and compare it with other type of containments. The paper discusses the literature regarding various types of existing containments in the world. In depth study of design practice for cylinder and various types of heads have been discussed. Also discusses the finite element modeling of the containment, analysis for normal and accidental loads and the design qualification as per the ASME and IS-800 codes. In the conclusion the advantage of steel containment is highlighted with the small discussion on the newer trends of construction. (author)

Characterization of D2 tool steel friction surfaced coatings over low carbon steel

International Nuclear Information System (INIS)

Sekharbabu, R.; Rafi, H. Khalid; Rao, K. Prasad

2013-01-01

Highlights: • Solid state coating by friction surfacing method. • D2 tool steel is coated over relatively softer low carbon steel. • Defect free interface between tool steel coating and low carbon steel substrate. • D2 coatings exhibited higher hardness and good wear resistance. • Highly refined martensitic microstructure in the coating. - Abstract: In this work D2 tool steel coating is produced over a low carbon steel substrate using friction surfacing process. The process parameters are optimized to get a defect free coating. Microstructural characterization is carried out using optical microscopy, scanning electron microscopy and X-ray diffraction. Infrared thermography is used to measure the thermal profile during friction surfacing of D2 steel. Wear performance of the coating is studied using Pin-on-Disk wear tests. A lower rotational speed of the consumable rod and higher translational speed of the substrate is found to result in thinner coatings. Friction surfaced D2 steel coating showed fine-grained martensitic microstructure compared to the as-received consumable rod which showed predominantly ferrite microstructure. Refinement of carbides in the coating is observed due to the stirring action of the process. The infrared thermography studies showed the peak temperature attained by the D2 coating to be about 1200 °C. The combined effect of martensitic microstructure and refined carbides resulted in higher hardness and wear resistance of the coating

Methods of making bainitic steel materials

Science.gov (United States)

Bakas, Michael Paul; Chu, Henry Shiu-Hung; Zagula, Thomas Andrew; Langhorst, Benjamin Robert

2018-01-16

Methods of making bainitic steels may involve austenitizing a quantity of steel by exposing the quantity of steel to a first temperature. A composition of the quantity of steel may be configured to impede formation of non-bainite ferrite, pearlite, and Widmanstatten ferrite. The quantity of steel may be heat-treated to form bainite by exposing the quantity of steel to a second, lower temperature. The second, lower temperature may be stabilized by exposing the quantity of steel to the second, lower temperature in the presence of a thermal ballast.

Milled Die Steel Surface Roughness Correlation with Steel Sheet Friction

DEFF Research Database (Denmark)

Berglund, J.; Brown, C.A.; Rosén, B.-G.

2010-01-01

This work investigates correlations between the surface topography ofmilled steel dies and friction with steel sheet. Several die surfaces were prepared by milling. Friction was measured in bending under tension testing. Linear regression coefficients (R2) between the friction and texture...

Flued head replacement alternatives

International Nuclear Information System (INIS)

Smetters, J.L.

1987-01-01

This paper discusses flued head replacement options. Section 2 discusses complete flued head replacement with a design that eliminates the inaccessible welds. Section 3 discusses alternate flued head support designs that can drastically reduce flued head installation costs. Section 4 describes partial flued head replacement designs. Finally, Section 5 discusses flued head analysis methods. (orig./GL)

Bottom head assembly

International Nuclear Information System (INIS)

Fife, A.B.

1998-01-01

A bottom head dome assembly is described which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome. The bottom head dome has a plurality of openings extending there through. The liner also has a plurality of openings extending there through, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending there through, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore there through, and each support stub bore aligns with a respective bottom head dome opening. 2 figs

The compatibility of stainless steels with particles and powders of uranium carbide and low-sulphur UCS fuels

International Nuclear Information System (INIS)

Venter, S.

1978-05-01

Slightly hyperstoichiometric (U,Pu)C is a potential nuclear fuel for fast breeder reactors. The excess carbon above the stoichiometric amount results in a higher carbon activity in the fuel, and carbon is transferred to the stainless steel cladding, resulting in embrittlement of the cladding. It is with this problem of carbon transfer from the fuel to the cladding that this thesis is concerned. For practical reasons, UC and not (U,Pu)C was used as the fuel. The theory of decarburisation of carbide fuel and the carburisation of stainless steel, the facilities constructed for the project at the Atomic Energy Board, and the experimental techniques used, including preparation of the fuels, are discussed. The effect of a number of variables of uranium carbide fuel on its compatibility behaviour with stainless steels was investigated, as well as the effect om microstructure and type of stainless steel (304, 304 L and 316) on the rate of carburisation. These studies can be briefly summarised under the following headings: powder-particle size; surface oxidation of uranium carbide; preparation temperature of uranium carbide; low sulfur UCS fuels; uranium sulfide and the microstructure and type of steel. The author concludes that: the effect of surface oxidation and particle size must be taken into account when evaluating out-of-pile tests; the possible effects of surface oxidation must be taken into account when considering vibro-compacted carbide fuels; there is no advantage in replacing a fraction of the carbon atoms by sulphur atoms in slightly hyperstoichiometric carbide fuels, and the type and thermo-mechanical treatment of the stainless steel used as cladding material in a fuel pin is not important as far as the rate of carburisation by the fuel is concerned

Steels from materials science to structural engineering

CERN Document Server

Sha, Wei

2013-01-01

Steels and computer-based modelling are fast growing fields in materials science as well as structural engineering, demonstrated by the large amount of recent literature. Steels: From Materials Science to Structural Engineering combines steels research and model development, including the application of modelling techniques in steels.  The latest research includes structural engineering modelling, and novel, prototype alloy steels such as heat-resistant steel, nitride-strengthened ferritic/martensitic steel and low nickel maraging steel.  Researchers studying steels will find the topics vital to their work.  Materials experts will be able to learn about steels used in structural engineering as well as modelling and apply this increasingly important technique in their steel materials research and development. 

Microstructural characterisation and corrosion performance of old railway girder bridge steel and modern weathering structural steel

International Nuclear Information System (INIS)

Tewary, N.K.; Kundu, A.; Nandi, R.; Saha, J.K.; Ghosh, S.K.

2016-01-01

Highlights: • Microstructure and corrosion performance are compared for two structural steels. • Microstructure evolution shows primarily ferrite-pearlite in both the steels. • Steels show higher corrosion rate in 1% HCl solution than in 3.5% NaCl solution. • The corrosion products show the presence of oxide, hydroxide and oxy-hydroxides. • The corroded surface reveals morphologies like flowery, cotton balls and rosette. - Abstract: A comparison on microstructure and corrosion performance has been made between the two structural steels used in old railway girder bridge (Sample A) and modern grades of weathering structural steel (Sample B). The microstructures, viewed under optical microscope and scanning electron microscope (SEM), show mainly ferrite-pearlite phase constituents in both the steels, A and B. The phase fraction analysis shows higher amount of pearlite in steel A compared to that of steel B. The grain size of steel A is larger than that of steel B under identical processing condition. The immersion corrosion test in 3.5% NaCl shows that the corrosion rate of steel A increases with time, while the same for steel B decreases with time. On the other hand, corrosion test in 1% HCl shows that the corrosion rate of both steel A and B is higher as compared to that of NaCl which always decreases with time. The XRD analysis of corrosion products show the presence of many oxides, hydroxide and oxy-hydroxide like Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH), Akaganeite (β-FeOOH), Magnetite (Fe_3O_4) and Maghemite (γ-Fe_2O_3) in both the steels. The SEM images of corroded surfaces reveal different morphologies like flowery, cotton balls and rosette etc. which indicate that the corrosion products primarily contain Lepidocrocite (γ-FeOOH), Goethite (α-FeOOH) and Akaganeite (β-FeOOH).

Microstructural characterization in dissimilar friction stir welding between 304 stainless steel and st37 steel

International Nuclear Information System (INIS)

Jafarzadegan, M.; Feng, A.H.; Abdollah-zadeh, A.; Saeid, T.; Shen, J.; Assadi, H.

2012-01-01

In the present study, 3 mm-thick plates of 304 stainless steel and st37 steel were welded together by friction stir welding at a welding speed of 50 mm/min and tool rotational speed of 400 and 800 rpm. X-ray diffraction test was carried out to study the phases which might be formed in the welds. Metallographic examinations, and tensile and microhardness tests were used to analyze the microstructure and mechanical properties of the joint. Four different zones were found in the weld area except the base metals. In the stir zone of the 304 stainless steel, a refined grain structure with some features of dynamic recrystallization was evidenced. A thermomechanically-affected zone was characterized on the 304 steel side with features of dynamic recovery. In the other side of the stir zone, the hot deformation of the st37 steel in the austenite region produced small austenite grains and these grains transformed to fine ferrite and pearlite and some products of displacive transformations such as Widmanstatten ferrite and martensite by cooling the material after friction stir welding. The heat-affected zone in the st37 steel side showed partially and fully refined microstructures like fusion welding processes. The recrystallization in the 304 steel and the transformations in the st37 steel enhanced the hardness of the weld area and therefore, improved the tensile properties of the joint. - Highlights: ► FSW produced sound welds between st37 low carbon steel and 304 stainless steel. ► The SZ of the st37 steel contained some products of allotropic transformation. ► The material in the SZ of the 304 steel showed features of dynamic recrystallization. ► The finer microstructure in the SZ increased the hardness and tensile strength.

Comparison of the performance of concrete-filled steel tubular and hollow steel diagrid buildings

Science.gov (United States)

Peter, Minu Ann; S, Sajith A.; Nagarajan, Praveen

2018-03-01

In the recent construction scenario, diagrid structures are becoming a popular high-rise building structural system. Diagrid structures consist of diagonals in the perimeter and an interior core. The corner and interior vertical columns are not required due to the structural efficiency of diagrid structural systems. Steel and concrete are commonly used material for diagrid. An alternate material for diagrid is concrete-filled steel tube (CFST). CFST incorporates the advantages of both steel and concrete. In CFST, the inward buckling of the steel tube is effectively prevented by the filled concrete. The compressive strength of concrete increases due to the tri-axial state of stress in concrete induced by the steel tube. The longitudinal as well as lateral reinforcement to the concrete core is also provided by the steel tube. This paper compares the performance of CFST and steel diagrid buildings using linear static analysis. For this purpose, a 12 storey and 36 storey building are analysed using finite element method and CFST diagrid building is found to perform better.

Hydrogen gas embrittlement of stainless steels mainly austenitic steels. Volumes 1 and 2

International Nuclear Information System (INIS)

Azou, P.

1988-01-01

Steel behavior in regard to hydrogen is examined especially austenitic steels. Gamma steels are studied particularly the series 300 with various stabilities and gamma steels with improved elasticity limit for intermetallic phase precipitation and nitrogen additions. A two-phase structure γ + α' is also studied. All the samples are tested for mechanical behavior in gaseous hydrogen. Influence of metallurgical effects and of testing conditions on hydrogen embrittlement are evidenced. Microstructure resulting from mechanical or heat treatments, dislocation motion during plastic deformation and influence of deformation rate are studied in detail [fr

Inhibitory effect of non-ionic surfactants of the TRITON-X series on the corrosion of carbon steel in sulphuric acid

International Nuclear Information System (INIS)

Fuchs-Godec, R.

2007-01-01

The corrosion inhibition characteristics of non-ionic surfactants of the TRITON-X series, known as TRITON-X-100 and TRITON-X-405, on stainless steel (SS) type X4Cr13 in sulphuric acid were investigated by potentiodynamic polarisation measurements. It was found that these surfactants act as good inhibitors of the corrosion of stainless steel in 2 mol L -1 H 2 SO 4 solution, but the inhibition efficiency strongly depends on the electrode potential. The polarisation data showed that the non-ionic surfactants used in this study acted as mixed-type inhibitors and adsorb on the stainless steel surface, in agreement with the Flory-Huggins adsorption isotherm. Calculated ΔG ads values are -57.79 kJ mol -1 for TRITON-X-100, and -87.5 kJ mol -1 for TRITON-X-405. From the molecular structure it can be supposed that these surfactants adsorb on the metal surface through two lone pairs of electrons on the oxygen atoms of the hydrophilic head group, suggesting a chemisorption mechanism

Some comments about the situation of the Steel Industry in the Arab Countries (Arab Steel Summit)

International Nuclear Information System (INIS)

Haidar, Y.; Astier, J.

2009-01-01

The Arab Steel Summit, that convened in Abu Dhabi in April, gave us another opportunity to review the situation of the Arab Iron and Steel Industry, with regard to the present World economic context. We will address: - the World situation of steel production, focusing on the Arab Countries; - the related situation of steel consumption; - the steel trade, including imports, exports and prices; - the consequences for technology and economy. (authors)

Challenges in Special Steel Making

Science.gov (United States)

Balachandran, G.

2018-02-01

Special bar quality [SBQ] is a long steel product where an assured quality is delivered by the steel mill to its customer. The bars have enhanced tolerance to higher stress application and it is demanded for specialised component making. The SBQ bars are sought for component making processing units such as closed die hot forging, hot extrusion, cold forging, machining, heat treatment, welding operations. The final component quality of the secondary processing units depends on the quality maintained at the steel maker end along with quality maintained at the fabricator end. Thus, quality control is ensured at every unit process stages. The various market segments catered to by SBQ steel segment is ever growing and is reviewed. Steel mills need adequate infrastructure and technological capability to make these higher quality steels. Some of the critical stages of processing SBQ and the critical quality maintenance parameters at the steel mill in the manufacture has been brought out.

Trends in steel technology

International Nuclear Information System (INIS)

Anon.

1980-01-01

Dual phase steels, composite products, and microalloyed steels are making inroads in the automotive industry applications for bumpers, automotive parts, bodies, mechanical parts, suspension and steering equipment and truck bumpers. New steels are also used to support solar mirrors and cells, in corrosive environments in the oil and gas industry, fusion reactors, and pressure vessels in nuclear power plants

Analysis of the Behaviour of Composite Steel and Steel Fiber Reinforced Concrete Slabs

Directory of Open Access Journals (Sweden)

Mindaugas Petkevičius

2011-04-01

Full Text Available There was a pending influence of steel fiber on the strength and stiffness of composite steel–concrete slabs under statical short–time load. Steel profiled sheeting and steel fiber reinforced concrete were used for specimens. Four composite slabs were made. Experimental investigations into the behaviour and influence of steel fiber reinforced concrete in composite slabs were conducted. Transverse, longitudinal, shear deformation and deflection of the slab were measured. The results indicated that the use of steel fiber in composite slabs was effective: strength was 20–24 % higher and the meanings of deflections under the action of the bending moment were 0,6MR (where MR is the bending moment at failure of the slabs and were 16–18 % lower for slabs with usual concrete. Article in Lithuanian

What are Head Cavities? - A History of Studies on Vertebrate Head Segmentation.

Science.gov (United States)

Kuratani, Shigeru; Adachi, Noritaka

2016-06-01

Motivated by the discovery of segmental epithelial coeloms, or "head cavities," in elasmobranch embryos toward the end of the 19th century, the debate over the presence of mesodermal segments in the vertebrate head became a central problem in comparative embryology. The classical segmental view assumed only one type of metamerism in the vertebrate head, in which each metamere was thought to contain one head somite and one pharyngeal arch, innervated by a set of cranial nerves serially homologous to dorsal and ventral roots of spinal nerves. The non-segmental view, on the other hand, rejected the somite-like properties of head cavities. A series of small mesodermal cysts in early Torpedo embryos, which were thought to represent true somite homologs, provided a third possible view on the nature of the vertebrate head. Recent molecular developmental data have shed new light on the vertebrate head problem, explaining that head mesoderm evolved, not by the modification of rostral somites of an amphioxus-like ancestor, but through the polarization of unspecified paraxial mesoderm into head mesoderm anteriorly and trunk somites posteriorly.

Ductile fracture of two-phase welds under 77K. [Steel-EhP810, steel-EhP666, steel-08Kh18N10T, steel-EhP659-VI, steel-chP810

Energy Technology Data Exchange (ETDEWEB)

Yushchenko, K.A.; Voronin, S.A.; Pustovit, A.I.; Shavel' , A.V.

The effect of the type of welding and fillers on crack resistance of welded joints high-strength steel EhP810 and its various compounds with steels EhP666, 08Kh18N10T has been studied. For the welding of steel EhP810 with steels EhP810, EhP666, 08Kh18N10T electron-beam, automatic, argon tungsten arc with non-consumable electrode with various fillers, as well as argon metal-arc welding with consumable electrode, were used. It is shown, that for a joint, made by electron-beam welding, parameters sigmasub(u), Ksub(IcJ), KCV are higher than for a joint of a similar phase structure made using filler wire EhP659-VI. It is explained by the fact, that during electron-beam welding joint metal refining takes place, which removes gases. In welded joints of chP810 steel, having joints with austenitic structure, characteristic of crack resistance Ssub(c) increases by more than 0.2 mm in contrast to two-phase joints, which conventional yield strength at 77 K exceeds 1000 MPa. It is worth mentioning, that for other classes of steels formation of two-phase structure of joint increases welded joint resistance to brittle fracture. It is possible to obtain the required structure of joint with assigned level of resistance to brittle fracture by means of the use of different fillers, optimum and welding procedure, regulating the part of the basic metal in joint content.

Steel Industry Wastes.

Science.gov (United States)

Schmidtke, N. W.; Averill, D. W.

1978-01-01

Presents a literature review of wastes from steel industry, covering publications of 1976-77. This review covers: (1) coke production; (2) iron and steel production; (3) rolling operations; and (4) surface treatment. A list of 133 references is also presented. (NM)

Fatigue damage of steel components

DEFF Research Database (Denmark)

Fæster, Søren; Zhang, Xiaodan; Huang, Xiaoxu

2014-01-01

Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials......Railway rails and the inner ring in roller bearings in wind turbines are both experiencing steel-to-steel contact in small areas with huge loads resulting in extremely high stresses in the base materials...

Corrosion of mild steel and stainless steel by marine Vibrio sp.

Digital Repository Service at National Institute of Oceanography (India)

PrabhaDevi; Wagh, A.B.

Microbially induced corrosion (MIC) of stainless steel and mild steel coupons exposed to media with and without a bacterial culture Vibrio sp. was studied using Scanning Electron Microscope (SEM). Pitting type of corrosion was noticed which was more...

The Study for Recycling NORM - Contaminated Steel Scraps from Steel Industry

International Nuclear Information System (INIS)

Tsai, K. F.; Lee, Y. S.; Chao, H. E.

2003-01-01

Since 1994, most of the major steel industries in Taiwan have installed portal monitor to detect the abnormal radiation in metal scrap feed. As a result, the discovery of NORM (Naturally Occurring Radioactive Material) has increased in recent years. In order to save the natural resources and promote radiation protection, an experimental melting process for the NORM contaminated steel scraps was carried out by the Institute of Nuclear Energy Research (INER) Taiwan, ROC. The experimental melting process has a pretreatment step that includes a series of cutting and removal of scales, sludge, as well as combustible and volatile materials on/in the steel scraps. After pretreatment the surface of the steel scraps are relatively clean. Then the scraps are melted by a pilot-type induction furnace. This experiment finally produced seven ingots with a total weight of 2,849 kg and 96.8% recovery. All of the surface dose rates are of the background values. The activity concentrations of these ingots are also below the regulatory criteria. Thus, these NORM-bearing steel scraps are ready for recycling. This study has been granted by the regulatory authority

Radial head button holing: a cause of irreducible anterior radial head dislocation

Energy Technology Data Exchange (ETDEWEB)

Shin, Su-Mi; Chai, Jee Won; You, Ja Yeon; Park, Jina [Seoul National University Seoul Metropolitan Government Boramae Medical Center, Department of Radiology, Seoul (Korea, Republic of); Bae, Kee Jeong [Seoul National University Seoul Metropolitan Government Boramae Medical Center, Department of Orthopedic Surgery, Seoul (Korea, Republic of)

2016-10-15

''Buttonholing'' of the radial head through the anterior joint capsule is a known cause of irreducible anterior radial head dislocation associated with Monteggia injuries in pediatric patients. To the best of our knowledge, no report has described an injury consisting of buttonholing of the radial head through the annular ligament and a simultaneous radial head fracture in an adolescent. In the present case, the radiographic findings were a radial head fracture with anterior dislocation and lack of the anterior fat pad sign. Magnetic resonance imaging (MRI) clearly demonstrated anterior dislocation of the fractured radial head through the torn annular ligament. The anterior joint capsule and proximal portion of the annular ligament were interposed between the radial head and capitellum, preventing closed reduction of the radial head. Familiarity with this condition and imaging findings will aid clinicians to make a proper diagnosis and fast decision to perform an open reduction. (orig.)

Steel: Price and Policy Issues

National Research Council Canada - National Science Library

Cooney, Stephen

2006-01-01

Steel prices remain at historically elevated levels. The rapid growth of steel production and demand in China is widely considered as a major cause of the increases in both steel prices and the prices of steelmaking inputs...

Remote maintenance in the building of the reactor of power plants

International Nuclear Information System (INIS)

Bonin, R.

1984-01-01

Examples describing the different operations requiring remote control for reactor maintenance are given. These operations include: refueling machines (for closure stud, vessel flange cleaning, screwing plug for channel head, swimming pool decontamination) in-service inspection machines (MIS, spider for eddy current testing of steam generator, television) and routine or accidental maintenance (leak detection in water boxes, maintenance spider, opening or closing primary manways, decontamination manipulators and various automatic control devices) [fr

FE-simulation of the viscoplastic behaviour of different RPV steels in the frame of in-vessel melt retentions scenarios

International Nuclear Information System (INIS)

Altstadt, E.; Willschuetz, H.G.; Mueller, G.

2004-01-01

Assuming the hypothetical scenario of a severe accident with subsequent core meltdown and formation of a melt pool in the reactor pressure vessel (RPV) lower plenum of a Light Water Reactor (LWR) leads to the question about the behavior of the RPV. One accident management strategy could be to stabilize the in-vessel debris configuration in the RPV as one major barrier against uncontrolled release of heat and radio nuclides. To get an improved understanding and knowledge of the melt pool convection and the vessel creep and possible failure processes and modes occurring during the late phase of a core melt down accident the FOREVER-experiments (Failure Of REactor VEssel Retention) have been performed at the Division of Nuclear Power Safety of the Royal Institute of Technology Stockholm. These experiments are simulating the behavior of the lower head of the RPV under the thermal loads of a convecting melt pool with decay heating, and under the pressure loads that the vessel experiences in a depressurization scenario. The geometrical scale of the experiments is 1:10 compared to a common LWR. This paper deals with the experimental, numerical, and metallographical results of the creep failure experiment EC-FOREVER-4, where the American pressure vessel steel SA533B was applied for the lower head. For comparison the results of the experiment EC-FOREVER-3B, build of the French 16MND5 steel, are discussed, too. Emphasis is put on the differences in the viscoplastic behaviour of different heats of the RPV steel. For this purpose, the creep tests in the frame of the LHF/OLHF experiments are reviewed, too. As a hypothesis it is stated that the sulphur content could be responsible for differences in the creep behaviour. (orig.)

In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

International Nuclear Information System (INIS)

Itty, Pierre-Adrien; Serdar, Marijana; Meral, Cagla; Parkinson, Dula; MacDowell, Alastair A.; Bjegović, Dubravka; Monteiro, Paulo J.M.

2014-01-01

Highlights: • The morphology of the corrosion of steel in cement paste was studied in situ. • During galvanostatic corrosion, carbon steel reinforcement corroded homogeneously. • On ferritic stainless steel, deep corrosion pits formed and caused wider cracks. • The measured rate of steel loss correlated well with Faraday’s law of electrolysis. - Abstract: In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover

Hot tensile behaviour in silicon-killed boron microalloyed steels

Science.gov (United States)

Chown, Lesley H.; Cornish, Lesley A.

2017-10-01

Low carbon steel for drawing and cold heading applications should have low strength, high ductility and low strain ageing rates. To achieve this, nitrogen must be removed from solid solution, which can be done by low additions of boron. A wire producer had been experiencing occasional problems with severe cracking on silicon-killed, boron steel billets during continuous casting, but the solution was not obvious. Samples from four billets, each from different casts, were removed for analysis and testing. The tested steel compositions were within the specification limits, with boron to nitrogen ratios of 0.40-1.19. Hot ductility testing was performed on a Gleeble 1500 using parameters approximating the capabilities of this particular billet caster. The steel specimens were subjected to in situ melting, then cooled at a rate of 2 C.s-1 to temperatures in the range 750-1250°C, where they were then pulled to failure at a strain rate of 8x10-4 s-1. In this work, it was found that both the boron to nitrogen ratio and the manganese to sulphur ratio influenced the hot ductility and hence the crack susceptibility. Excellent hot ductility was found for B:N ratios above 1.0, which confirmed that the B:N ratio should be above a stoichiometric value of 0.8 to remove all nitrogen from solid solution. TEM analysis showed that coarse BN precipitates nucleated on other precipitates, such as (Fe,Mn)S, which have relatively low melting points, and are detrimental to hot ductility. Low Mn:S ratios of 10 - 12 were shown to promote precipitation of FeS, so a Mn:S > 14 was recommended. A narrower billet surface temperature range for straightening was recommended to prevent transverse surface cracking. Additionally, analysis of industrial casting data showed that the scrap percentage due to transverse cracking increased significantly for Mn:S < 14. An exponential decay relationship between the manganese to sulphur ratio and the average scrap percentage due to transverse cracking was

Fracture Mechanisms in Steel Castings

Directory of Open Access Journals (Sweden)

Stradomski Z.

2013-09-01

Full Text Available The investigations were inspired with the problem of cracking of steel castings during the production process. A single mechanism of decohesion - the intergranular one - occurs in the case of hot cracking, while a variety of structural factors is decisive for hot cracking initiation, depending on chemical composition of the cast steel. The low-carbon and low-alloyed steel castings crack due to the presence of the type II sulphides, the cause of cracking of the high-carbon tool cast steels is the net of secondary cementite and/or ledeburite precipitated along the boundaries of solidified grains. Also the brittle phosphor and carbide eutectics precipitated in the final stage solidification are responsible for cracking of castings made of Hadfield steel. The examination of mechanical properties at 1050°C revealed low or very low strength of high-carbon cast steels.

On choice of tempered steels

International Nuclear Information System (INIS)

Govorov, A.A.; Pan'shin, I.F.; Rakhmanov, V.I.

1978-01-01

For the purpose of developing a graphical method for choosing structural steels, a change in the propagation work of a crack and in the critical temperature of brittleness of 40, 40Kh, 40KhN, and 40KhNM steels, was examined depending on the hardness after hardening and tempering. A diagram enabling to choose the grade of steel for making an article of known dimensions according to the preset values of its mechanical properties has been plotted. The developed selection scheme takes into account the hardenability of steels and the influence of the hardness after thermal treatment on the cold-shortness of steel

Volatilization from PCA steel alloy

Energy Technology Data Exchange (ETDEWEB)

Hagrman, D.L.; Smolik, G.R.; McCarthy, K.A.; Petti, D.A.

1996-08-01

The mobilizations of key components from Primary Candidate Alloy (PCA) steel alloy have been measured with laboratory-scale experiments. The experiments indicate most of the mobilization from PCA steel is due to oxide formation and spalling but that the spalled particles are large enough to settle rapidly. Based on the experiments, models for the volatization of iron, manganese, and cobalt from PCA steel in steam and molybdenum from PCA steel in air have been derived.

Risk of lung cancer according to mild steel and stainless steel welding

DEFF Research Database (Denmark)

Sørensen, Anita Rath; Thulstrup, Ane Marie; Hansen, Johnni

2007-01-01

OBJECTIVES: Whether the elevated risk of lung cancer observed among welders is caused by welding emissions or by confounding from smoking or asbestos exposure is still not resolved. This question was addressed in a cohort with a long follow-up and quantified estimates of individual exposure.......06-1.70)]. Among the stainless steel welders, the risk increased significantly with increasing accumulative welding particulate exposure, while no exposure-response relation was found for mild steel welders, even after adjustment for tobacco smoking and asbestos exposure. CONCLUSIONS: The study corroborates...... earlier findings that welders have an increased risk of lung cancer. While exposure-response relations indicate carcinogenic effects related to stainless steel welding, it is still unresolved whether the mild steel welding process carries a carcinogenic risk....

Review on Cold-Formed Steel Connections

Science.gov (United States)

Tan, Cher Siang; Mohammad, Shahrin; Md Tahir, Mahmood; Shek, Poi Ngian

2014-01-01

The concept of cold-formed light steel framing construction has been widespread after understanding its structural characteristics with massive research works over the years. Connection serves as one of the important elements for light steel framing in order to achieve its structural stability. Compared to hot-rolled steel sections, cold-formed steel connections perform dissimilarity due to the thin-walled behaviour. This paper aims to review current researches on cold-formed steel connections, particularly for screw connections, storage rack connections, welded connections, and bolted connections. The performance of these connections in the design of cold-formed steel structures is discussed. PMID:24688448

Radiation embrittlement of WWER 440 pressure vessel steel and of some improved steels by western producers

International Nuclear Information System (INIS)

Koutsky, J.; Vacek, M.; Stoces, B.; Pav, T.; Otruba, J.; Novosad, P.; Brumovsky, M.

1982-01-01

The resistance was studied of Cr-Mo-V type steel 15Kh2MFA to radiation embrittlement at an irradiation temperature of around 288 degC. Studied was the steel used for the manufacture of the pressure vessel of the Paks nuclear reactor in Hungary. The obtained results of radiation embrittlement and hardening of steel 15Kh2MFA were compared with similar values of Mn-Ni-Mo type steels A 533-B and A 508 manufactured by leading western manufacturers within the international research programme coordinated by the IAEA. It was found that the resistance of steel 15Kh2MFA to radiation embrittlement is comparable with steels A 533-B and A 508 by western manufacturers. (author)

Structural fatigue test results for large wind turbine blade sections

Science.gov (United States)

Faddoul, J. R.; Sullivan, T. L.

1982-01-01

In order to provide quantitative information on the operating life capabilities of wind turbine rotor blade concepts for root-end load transfer, a series of cantilever beam fatigue tests was conducted. Fatigue tests were conducted on a laminated wood blade with bonded steel studs, a low cost steel spar (utility pole) with a welded flange, a utility pole with additional root-end thickness provided by a swaged collar, fiberglass spars with both bonded and nonbonded fittings, and, finally, an aluminum blade with a bolted steel fitting (Lockheed Mod-0 blade). Photographs, data, and conclusions for each of these tests are presented. In addition, the aluminum blade test results are compared to field failure information; these results provide evidence that the cantilever beam type of fatigue test is a satisfactory method for obtaining qualitative data on blade life expectancy and for identifying structurally underdesigned areas (hot spots).

A comparison of the iraddiated tensile properties of a high-manganese austenitic steel and type 316 stainless steel

International Nuclear Information System (INIS)

Klueh, R.L.; Grossbeck, M.L.

1984-01-01

The USSR steel EP-838 is a high-manganese, low-nickel steel that also has lower chromium and molybdenum than type 316 stainless steel. Tensile specimens of 20%-cold-worked EP-838 and type 316 stainless steel were irradiated in the High Flux Isotope Reactor (HFIR) at the coolant temperature (approx.=50 0 C). A displacement damage level of 5.2 dpa was reached for the EP-838 and up to 9.5 dpa for the type 316 stainless steel. Tensile tests at room temperature and 300 0 C on the two steels indicated that the irradiation led to increased strength and decreased ductility compared to the unirradiated steels. Although the 0.2% yield stress of the type 316 stainless steel in the unirradiated condition was greater than that for the EP-838, after irradiation there was essentially no difference between the strength or ductility of the two steels. The results indicate that the replacement of the majority of the nickel by manganese and a reduction of chromium and molybdenum in an austenitic stainless steel of composition near that for type 316 stainless steel has little effect on the irradiated and unirradiated tensile properties at low temperatures. (orig.)

Ductility of high chromium stainless steels

International Nuclear Information System (INIS)

Peretyat'ko, V.N.; Kazantsev, A.A.

1997-01-01

Aimed to optimize the hot working conditions for high chromium stainless steels the experiments were carried in the temperature range of 800-1300 deg C using hot torsion tests and cylindrical specimens of ferritic and ferritic-martensitic steels 08Kh13, 12Kh13, 20Kh13, 30Kh13 and 40Kh13. Testing results showed that steel plasticity varies in a wide range depending on carbon content. Steels of lesser carbon concentration (08Kh13 and 12Kh13) exhibit a sharp increase in plasticity with a temperature rise, especially in the interval of 1200-1250 deg C. Steels 20Kh13 and 30Kh13 display insignificant plasticity increasing, whereas plastic properties of steel 40Kh13 increase noticeably in the range of 1000-1300 deg C. It is shown that optimal hot working conditions for specific steel must be selected with account of steel phase composition at high temperatures

Steels for nuclear power. I

International Nuclear Information System (INIS)

Bohusova, O.; Brumovsky, M.; Cukr, B.; Hatle, Z.; Protiva, K.; Stefec, R.; Urban, A.; Zidek, M.

1976-01-01

The principles are listed of nuclear reactor operation and the reactors are classified by neutron energy, fuel and moderator designs, purpose and type of moderator. The trend and the development of light-water reactor applications are described. The fundamental operating parameters of the WWER type reactors are indicated. The effect is discussed of neutron radiation on reactor structural materials. The characteristics are described of steel corrosion due to the contact of the steel with steam or sodium in the primary coolant circuit. The reasons for stress corrosion are given and the effects of radiation on corrosion are listed. The requirements and criteria are given for the choice of low-alloy steel for the manufacture of pressure vessels, volume compensators, steam generators, cooling conduits and containment. A survey is given of most frequently used steels for pressure vessels and of the mechanical and structural properties thereof. The basic requirements for the properties of steel used in the primary coolant circuit are as follows: sufficient strength in operating temperature, toughness, good weldability, resistance to corrosion and low brittleness following neutron irradiation. The materials are listed used for the components of light-water and breeder reactors. The production of corrosion-resistant steels is discussed with a view to raw materials, technology, steel-making processes, melting processes, induction furnace steel-making, and to selected special problems of the chemical composition of steels. The effects are mainly discussed of lead, bismuth and tin as well as of some other elements on hot working of high-alloy steels and on their structure. The problems of corrosion-resistant steel welding and of pressure vessel cladding are summed up. Also discussed is the question of the concept and safeguards of the safety of nuclear installation operation and a list is presented of most commonly used nondestructive materials testing methods. The current

Heading-vector navigation based on head-direction cells and path integration.

Science.gov (United States)

Kubie, John L; Fenton, André A

2009-05-01

Insect navigation is guided by heading vectors that are computed by path integration. Mammalian navigation models, on the other hand, are typically based on map-like place representations provided by hippocampal place cells. Such models compute optimal routes as a continuous series of locations that connect the current location to a goal. We propose a "heading-vector" model in which head-direction cells or their derivatives serve both as key elements in constructing the optimal route and as the straight-line guidance during route execution. The model is based on a memory structure termed the "shortcut matrix," which is constructed during the initial exploration of an environment when a set of shortcut vectors between sequential pairs of visited waypoint locations is stored. A mechanism is proposed for calculating and storing these vectors that relies on a hypothesized cell type termed an "accumulating head-direction cell." Following exploration, shortcut vectors connecting all pairs of waypoint locations are computed by vector arithmetic and stored in the shortcut matrix. On re-entry, when local view or place representations query the shortcut matrix with a current waypoint and goal, a shortcut trajectory is retrieved. Since the trajectory direction is in head-direction compass coordinates, navigation is accomplished by tracking the firing of head-direction cells that are tuned to the heading angle. Section 1 of the manuscript describes the properties of accumulating head-direction cells. It then shows how accumulating head-direction cells can store local vectors and perform vector arithmetic to perform path-integration-based homing. Section 2 describes the construction and use of the shortcut matrix for computing direct paths between any pair of locations that have been registered in the shortcut matrix. In the discussion, we analyze the advantages of heading-based navigation over map-based navigation. Finally, we survey behavioral evidence that nonhippocampal

The industrial ecology of steel

Energy Technology Data Exchange (ETDEWEB)

Considine, Timothy J.; Jablonowski, Christopher; Considine, Donita M.M.; Rao, Prasad G.

2001-03-26

This study performs an integrated assessment of new technology adoption in the steel industry. New coke, iron, and steel production technologies are discussed, and their economic and environmental characteristics are compared. Based upon detailed plant level data on cost and physical input-output relations by process, this study develops a simple mathematical optimization model of steel process choice. This model is then expanded to a life cycle context, accounting for environmental emissions generated during the production and transportation of energy and material inputs into steelmaking. This life-cycle optimization model provides a basis for evaluating the environmental impacts of existing and new iron and steel technologies. Five different plant configurations are examined, from conventional integrated steel production to completely scrap-based operations. Two cost criteria are used to evaluate technology choice: private and social cost, with the latter including the environmental damages associated with emissions. While scrap-based technologies clearly generate lower emissions in mass terms, their emissions of sulfur dioxide and nitrogen oxides are significantly higher. Using conventional damage cost estimates reported in the literature suggests that the social costs associated with scrap-based steel production are slightly higher than with integrated steel production. This suggests that adopting a life-cycle viewpoint can substantially affect environmental assessment of new technologies. Finally, this study also examines the impacts of carbon taxes on steel production costs and technology choice.

Head injury: audit of a clinical guideline to justify head CT

International Nuclear Information System (INIS)

Haydon, Nicholas B.

2013-01-01

Head injury causes significant morbidity and mortality, and there is contention about which patients to scan. The UK National Health Service Clinical Guideline (CG) 56 provides criteria for selecting patients with clinically important brain injury who may benefit from a head CT scan, while minimising the radiation and economic burden of scanning patients without significant injury. This study aims to audit the documentation of the use of these guidelines in a busy UK trauma hospital and discusses the comparison with an Australian (New South Wales (NSW) ) head injury guideline. A retrospective cohort study of 480 patients presenting with head injury to the emergency department over 2 months was performed. The patient notes were assessed for documentation of each aspect of the clinical guidelines. Criteria were established to assess the utilisation of the CG 56. A database of clinical data was amalgamated with the head CT scan results for each patient. For the UK CG 56, 73% of the criteria were documented, with the least documented being 'signs of basal skull fracture' and 'amnesia of events'. Thirty-two per cent of patients received head CT and of these, 24% (37 patients) were reported to have pathology. Twenty-four patients underwent head CT without clinical justification being documented, none of which had reported pathology on CT. The study shows that the head injury guidelines are not being fully utilised at a major UK trauma hospital, resulting in 5% of patients being exposed to ionising radiation without apparent documented clinical justification. The NSW guideline has distinct differences to the CG 56, with a more complex algorithm and an absence of specific time frames for head CT completion. The results suggest a need for further education and awareness of head injury clinical guidelines.

Head Trauma: First Aid

Science.gov (United States)

First aid Head trauma: First aid Head trauma: First aid By Mayo Clinic Staff Most head trauma involves injuries that are minor and don't require ... 21, 2015 Original article: http://www.mayoclinic.org/first-aid/first-aid-head-trauma/basics/ART-20056626 . Mayo ...

DETERMINANTS OF RETAINED EARNINGS IN PROFITABLE STEEL COMPANIES IN INDIA: A STUDY OF STEEL SECTOR

OpenAIRE

Dr. Sohaib Masood

2018-01-01

In this paper an attempt has been made to identify the important determinants of retained earnings in profitable steel companies in steel sector of India and which have impact on the retention of earnings of steel companies under study. Multiple linear regression is used to identify the determinants of retained earnings for a period of sixteen years. Also the importance of retained earnings as a source of finance for steel sector companies is also studied in the paper.

Advanced cold rolled steels for automotive applications

Energy Technology Data Exchange (ETDEWEB)

Hofmann, Harald; Mattissen, Dorothea; Schaumann, Thomas Wilhelm [ThyssenKrupp Steel AG, Center of Materials Excellence, Dortmund (Germany)

2009-01-15

Advanced high-strength steels offer a great potential for the further development of automobile bodies-in-white due to their combined mechanical properties of high formability and strength. They represent the first choice in material selection for strength and crash-relevant parts with challenging geometries. The intensive development of multiphase steels by ThyssenKrupp Steel has led to hot dip galvanizing concepts with an outstanding forming potential. Hot rolled, hot dip galvanized complex-phase steels are currently produced in addition to cold rolled dual phase (DP) and retained austenite (RA) or transformation induced plasticity (TRIP) steels. New continuously annealed grades of steel are being developed with tensile strength levels of up to 1000 MPa in combination with sufficient ductility for the high demands of structural automobile components. These steels make use of the classic advantages of microalloying as well as the principles of DP steels and RA / TRIP steels. Further improvement of properties will be reached by the new class of high manganese alloyed steels. (orig.)

Head and neck cancer

International Nuclear Information System (INIS)

Vogl, S.E.

1988-01-01

This book contains 10 chapters. Some of the titles are: Combined Surgical Resection and Irradiation for Head and Neck Cancers; Analysis of Radiation Therapy Oncology Group Head and Neck Database: Identification of Prognostic Factors and the Re-evaluation of American Joint Committee Stages; Combined Modality Approach to Head and Neck Cancer; Induction Combination Chemotherapy of Regionally Advanced Head and Neck Cancer; and Outcome after Complete Remission to Induction Chemotherapy in Head and Neck Cancer

Effect of head restraint backset on head-neck kinematics in whiplash.

Science.gov (United States)

Stemper, Brian D; Yoganandan, Narayan; Pintar, Frank A

2006-03-01

Although head restraints were introduced in the 1960s as a countermeasure for whiplash, their limited effectiveness has been attributed to incorrect positioning. The effect of backset on cervical segmental angulations, which were previously correlated with spinal injury, has not been delineated. Therefore, the practical restraint position to minimize injury remains unclear. A parametric study of increasing head restraint backset between 0 and 140mm was conducted using a comprehensively validated computational model. Head retraction values increased with increasing backset, reaching a maximum value of 53.5mm for backsets greater than 60mm. Segmental angulation magnitudes, greatest at levels C5-C6 and C6-C7, reached maximum values during the retraction phase and increased with increasing backset. Results were compared to a previously published head restraint rating system, wherein lower cervical extension magnitudes from this study exceeded mean physiologic limits for restraint positions rated good, acceptable, marginal, and poor. As head restraint contact was the limiting factor in head retraction and segmental angulations, the present study indicates that minimizing whiplash injury may be accomplished by limiting head restraint backset to less than 60mm either passively or actively after impact.

Contribution of headed studs to the composite behavior of the partially encased beams

OpenAIRE

De Nardin, Silvana; El Debs, Ana Lucia H. de C.

2008-01-01

A utilização de conectores de cisalhamento, especialmente os conectores tipo pino com cabeça, é um artifício comum para promover o comportamento misto aço-concreto. O embutimento da viga de aço no pavimento permite reduzir a altura total do pavimento sem comprometer a resistência e a rigidez. Nesse trabalho, são estudadas, experimentalmente, posições alternativas para conectores de cisalhamento tipo pino com cabeça em vigas de aço parcialmente revestidas com concreto. Logo, a principal variáv...

Processing and refinement of steel microstructure images for assisting in computerized heat treatment of plain carbon steel

Science.gov (United States)

Gupta, Shubhank; Panda, Aditi; Naskar, Ruchira; Mishra, Dinesh Kumar; Pal, Snehanshu

2017-11-01

Steels are alloys of iron and carbon, widely used in construction and other applications. The evolution of steel microstructure through various heat treatment processes is an important factor in controlling properties and performance of steel. Extensive experimentations have been performed to enhance the properties of steel by customizing heat treatment processes. However, experimental analyses are always associated with high resource requirements in terms of cost and time. As an alternative solution, we propose an image processing-based technique for refinement of raw plain carbon steel microstructure images, into a digital form, usable in experiments related to heat treatment processes of steel in diverse applications. The proposed work follows the conventional steps practiced by materials engineers in manual refinement of steel images; and it appropriately utilizes basic image processing techniques (including filtering, segmentation, opening, and clustering) to automate the whole process. The proposed refinement of steel microstructure images is aimed to enable computer-aided simulations of heat treatment of plain carbon steel, in a timely and cost-efficient manner; hence it is beneficial for the materials and metallurgy industry. Our experimental results prove the efficiency and effectiveness of the proposed technique.

Laser cutting of thick steel plates and simulated steel components using a 30 kW fiber laser

International Nuclear Information System (INIS)

Tamura, Koji; Ishigami, Ryoya; Yamagishi, Ryuichiro

2016-01-01

Laser cutting of thick steel plates and simulated steel components using a 30 kW fiber laser was studied for application to nuclear decommissioning. Successful cutting of carbon steel and stainless steel plates up to 300 mm in thickness was demonstrated, as was that of thick steel components such as simulated reactor vessel walls, a large pipe, and a gate valve. The results indicate that laser cutting applied to nuclear decommissioning is a promising technology. (author)

Strain-based failure criteria for steel containments

International Nuclear Information System (INIS)

Fanous, F.; Greimann, L.F.

1989-01-01

The Containment Integrity Division of the Sandia National Laboratories (Sandia) has been conducting a program to evaluate the performance of containment buildings with internal pressure. Sandia has suggested that in the absence of leakage past penetrations, containment buildings will fail by rupturing after large plastic strains are developed up to ultimate strain of the material. This paper represents a portion of work conducted at Ames Laboratory for Sandia, the objective of which was to identify fabrication details that may affect the performance of a containment building. Construction drawings for nine steel containment buildings were surveyed, and several significant strain concentration regions were identified by using recommendations from Sandia and Section NE-3217 of the ASME Boiler and Pressure Vessel Code. These following regions were identified as: eccentricities in stiffener patterns around penetrations, eccentricities in containment shell middle surface, flat plate covers used on spare penetrations, containment base connection details, and containment heads. Examples of each of these regions were analyzed by the finite-element method, by simplified equations or both. In the case of middle surface eccentricities, the strains were found to be self-limiting. Even though flat plates have primary strains, they are typically designed so as not to control. Bolts in the base connection have primary strains and may control. The circumferential compressive strains introduced at the knuckle during buckling of the containment head grow as the pressure increases, but are somewhat restricted by the meridional tension. Finally, three analysis techniques and their associated failure criteria for the analysis of containment strength are introduced. (orig.)

The use of steel and lead shieldings in radiotherapy rooms and its comparison with respect to neutrons doses at patients

International Nuclear Information System (INIS)

Silva, M.G.; Rebello, W.F.; Andrade, E.R.; Medeiros, M.P.C.; Mendes, R.M.S.; Braga, K.L.; Gomes, R.G.; Santos, R.F.G.

2015-01-01

The NCRP Report No. 151, Structural Shielding Design and Evaluation for Megavoltage X- and Gamma-Ray Radiotherapy Facilities, considers, in shielding calculations for radiotherapy rooms, the use of lead and/or steel to be applied on bunker walls. The NCRP Report calculations were performed foreseeing a better protection of people outside the radiotherapy room. However, contribution of lead and steel to patient dose should be taken into account for radioprotection purposes. This work presents calculations performed by MCNPX code in analyzing the Ambient Dose Equivalent due to neutron, H*(10) n , within a radiotherapy room, in the patients area, considering the use of additional shielding of 1 TVL of lead or 1 TVL of steel, positioned at the inner faces of walls and ceiling of a bunker. The head of the linear accelerator Varian 2100/2300 C/D was modeled working at 18MeV, with 5x5cm 2 , 10x10cm 2 , 20x20cm 2 , 30x30cm 2 and 40x40cm 2 openings for jaws and MLC and operating in eight gantry's angles. This study shows that the use of lead generates an average value of H*(10) n at patients area, 8.02% higher than the expected when using steel. Further studies should be performed based on experimental data for comparison with those from MCNPX simulation.

Electrochemical Corrosion Behavior of Carbon Steel and Hot Dip Galvanized Steel in Simulated Concrete Solution with Different pH Values

Directory of Open Access Journals (Sweden)

Wanchen XIE

2017-08-01

Full Text Available Hot dip galvanizing technology is now widely used as a method of protection for steel rebars. The corrosion behaviors of Q235 carbon steel and hot galvanized steel in a Ca(OH2 solution with a pH from 10 to 13 was investigated by electrode potential and polarization curves testing. The results indicated that carbon steel and hot galvanized steel were all passivated in a strong alkaline solution. The electrode potential of hot dip galvanized steel was lower than that of carbon steel; thus, hot dip galvanized steel can provide very good anodic protection for carbon steel. However, when the pH value reached 12.5, a polarity reversal occurred under the condition of a certain potential. Hot dip galvanized coating became a cathode, and the corrosion of carbon steel accelerated. The electrochemical behaviors and passivation abilities of hot dip galvanized steel and carbon steel were affected by pH. The higher the pH value was, the more easily they were passivated.DOI: http://dx.doi.org/10.5755/j01.ms.23.3.16675

Steel alloys

International Nuclear Information System (INIS)

Bloom, E.E.; Stiegler, J.O.; Rowcliffe, A.F.; Leitnaker, J.M.

1977-01-01

The invention deals with a fuel element for fast breeder reactors. It consits essentially of a uranium oxide, nitride, or carbide or a mixture of these fuels with a plutonium or thorium oxide, nitride, or carbide. The fuel elements are coated with an austenitic stainless steel alloy. Inside the fuel elements, vacancies or small cavities are produced by neutron effects which causes the steel coating to swell. According to the invention, swelling is prevented by a modification of type 304, 316, 321, or 12 K 72HV commercial steels. They consist mainly of Fe, Cr, and Ni in a ratio determined by a temary diagram. They may also contain 1.8 to 2.3% by weight of Mo and a fraction of Si (0.7 to 2% by weight) and Ti(0.10 to 0.5% by weight) to prevent cavity formation. They are structurally modified by cold working. (IHOE) [de

Clean steels for fusion

International Nuclear Information System (INIS)

Gelles, D.S.

1995-03-01

Fusion energy production has an inherent advantage over fission: a fuel supply with reduced long term radioactivity. One of the leading candidate materials for structural applications in a fusion reactor is a tungsten stabilized 9% chromium Martensitic steel. This alloy class is being considered because it offers the opportunity to maintain that advantage in the reactor structure as well as provide good high temperature strength and radiation induced swelling and embrittlement resistance. However, calculations indicate that to obtain acceptable radioactivity levels within 500 years after service, clean steel will be required because the niobium impurity levels must be kept below about 2 appm and nickel, molybdenum, nitrogen, copper, and aluminum must be intentionally restricted. International efforts are addressing the problems of clean steel production. Recently, a 5,000 kg heat was vacuum induction melted in Japan using high purity commercial raw materials giving niobium levels less than 0.7 appm. This paper reviews the need for reduced long term radioactivity, defines the advantageous properties of the tungsten stabilized Martensitic steel class, and describes the international efforts to produce acceptable clean steels

Thermal stability of manganese-stabilized stainless steels

International Nuclear Information System (INIS)

Klueh, R.L.; Kenik, E.A.

1993-01-01

Previous work on a series of experimental high-manganese reduced-activation austenitic stainless steels demonstrated that they have improved tensile properties relative to type 316 stainless steel in both the annealed and 20% cold-worked conditions. Steels were tested with an Fe-20Mn-12Cr-0.25C (in weight percent) base composition, to which various combinations of Ti, W, V, P, and B were added. Tensile tests have now been completed on these steels after thermal aging at 600 degrees C. Thermal stability varied with composition, but the alloys were as stable or more stable than type 316 stainless steel. the strength of the annealed steels increased slightly after aging to 5000 h, while a strength decrease occurred for the cold worked steel. In both conditions, a steel containing a combination of all the alloying elements was most stable and had the best strength after thermal aging 5000 h at 600 degrees C. Despite having much higher strength than 316 stainless steel after aging, the ductility of the strongest experimental alloy was still as good as that of 316 stainless steel

Sliding wear characteristics of carburized steels and thermally refined steels implanted with nitrogen ions

International Nuclear Information System (INIS)

Terashima, Keiichi; Koda, Hiroyuki; Takeuchi, Eiichi.

1995-01-01

In order to concretely examine the application of surface reforming by ion implantation, nitrogen ion implantation was applied to the thermally refined steels S45C and SCM440 and the carburized steel SCM415, which are high versatile steels for mechanical structures, and their friction and wear characteristics were examined. The results are summarized as follows. In the surface-reformed material, in which nitrogen was implanted for the purpose of improving the seizure durability of the carburized steel, the load-frictional coefficient curve in lubricated sliding friction was similar to that of the material without implantation, but it was recognized that the load at which seizure occurred reached 2000 kgf or more, and as the amount of implantation was more, the material withstood higher load. In the lubricated sliding friction using a pin-ring type wear testing machine of the thermally refined steels and those to which implantation was applied, it was recognized that the specific wear amount was less in the implanted steels than in those without implantation. The results of the analysis of the implanted surface layers and the friction surfaces are reported. (K.I.)

Influence of the Radiation Shield on the Temperature of Rails Rolled in the Reversing Mill

Directory of Open Access Journals (Sweden)

Gołdasz A.

2015-04-01

Full Text Available The paper presents a mathematical model of heat transfer during cooling of hot-rolled rails in the reversing mill. The influence of the radiation shield on the temperature of rolled rails has been analyzed. The heat transfer model for cooling a strip covered by the thermal shield has been presented. The two types of shields build of steel and aluminum sheets separated with insulating layer have been studded. Calculations have been performed with self developed software which utilizes the finite element method.

Larson-Miller Constant of Heat-Resistant Steel

Science.gov (United States)

Tamura, Manabu; Abe, Fujio; Shiba, Kiyoyuki; Sakasegawa, Hideo; Tanigawa, Hiroyasu

2013-06-01

Long-term rupture data for 79 types of heat-resistant steels including carbon steel, low-alloy steel, high-alloy steel, austenitic stainless steel, and superalloy were analyzed, and a constant for the Larson-Miller (LM) parameter was obtained in the current study for each material. The calculated LM constant, C, is approximately 20 for heat-resistant steels and alloys except for high-alloy martensitic steels with high creep resistance, for which C ≈ 30 . The apparent activation energy was also calculated, and the LM constant was found to be proportional to the apparent activation energy with a high correlation coefficient, which suggests that the LM constant is a material constant possessing intrinsic physical meaning. The contribution of the entropy change to the LM constant is not small, especially for several martensitic steels with large values of C. Deformation of such martensitic steels should accompany a large entropy change of 10 times the gas constant at least, besides the entropy change due to self-diffusion.

Properties of hot rolled steels for enamelling

International Nuclear Information System (INIS)

Gavrilovski, Dragica; Gavrilovski, Milorad

2003-01-01

The results of an investigation of the structure and properties of experimental produced hot rolled steels suitable for enamelling are presented in the paper. Hot rolled steels for enamelling represent a special group of the steels for conventional enamelling. Their quality has to be adapted to the method and conditions of enamelling. Therefore, these steels should meet some specific requirements. In addition to usual investigation of the chemical composition and mechanical properties, microstructure and quality of the steel surface also were investigated. The basic aim was to examine steels capability for enamelling, i. e. steels resistance to the fish scales phenomena, by trial enamelling, as well as quality of the steel - enamel contact surface, to evaluate the binding. Also, the changes of the mechanical properties, especially the yield point, during thermal treatment, as a very specific requirement, were investigated, by simplified method. Good results were obtained confirming the steels capability for enamelling. (Original)

Reduced-activation steels: present status and future development

International Nuclear Information System (INIS)

Klueh, R.L.

2007-01-01

Full text of publication follows: Reduced-activation steels for fusion reactor applications were developed in the 1980's to replace the commercial elevated- temperature steels first considered. In the United States, this involved replacing Sandvik HT9 and modified 9Cr-1Mo steels. Reduced-activation steels, which were developed for more rapid radioactivity decay following exposure in a fusion neutron environment, were patterned after the commercial steels they were to replace. The objective for the reduced-activation steels was that they have strengths (yield stress and ultimate tensile strength from room temperature to 600 deg. C) and impact toughness (measured in a Charpy test) comparable to or better than the steels they were replacing. That objective was achieved in reduced-activation steels developed in Japan, Europe, and the United States. Since the reduced-activation steels were developed in the 1980's, reactor designers have been interested designs for increased efficiency of future fusion plants. This means reactors will need to operate at higher temperatures-above 550 deg. C, which is the upper-temperature limit for the reduced-activation steels. Although the tensile and impact toughness of the reduced-activation steels exceed those of the commercial steels they were patterned after, their creep-rupture properties are inferior to some of the commercial steels they replaced. furthermore, they are much inferior to commercial steels that have been developed since the 1980's. Reasons for why the creep-rupture properties for the new commercial ferritic/martensitic steels are superior to the earlier commercial steels and the reduced-activation steels were examined. The reasons involve compositional changes that were made in the earlier commercial steels to give the new commercial steels their superior properties. Computational thermodynamics calculations were carried out to compare the expected equilibrium phases. It appears that similar changes in composition

In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

KAUST Repository

Itty, Pierre-Adrien

2014-06-01

In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover. © 2014 Elsevier Ltd.

In situ 3D monitoring of corrosion on carbon steel and ferritic stainless steel embedded in cement paste

KAUST Repository

Itty, Pierre-Adrien; Serdar, Marijana; Meral, Cagla; Parkinson, Dula; MacDowell, Alastair A.; Bjegović, Dubravka; Monteiro, Paulo J.M.

2014-01-01

In a X-ray microcomputed tomography study, active corrosion was induced by galvanostatically corroding steel embedded in cement paste. The results give insight into corrosion product build up, crack formation, leaching of products into the cracks and voids, and differences in morphology of corrosion attack in the case of carbon steel or stainless steel reinforcement. Carbon steel was homogeneously etched away with a homogeneous layer of corrosion products forming at the steel/cement paste interface. For ferritic stainless steel, pits were forming, concentrating the corrosion products locally, which led to more extensive damage on the cement paste cover. © 2014 Elsevier Ltd.

Scientific and Technological Principles of Development of New Cold-Resistant Arc-Steels (Steels for Arctic Applications)

Science.gov (United States)

Sych, O. V.; Khlusova, E. I.; Yashin, E. A.

2017-12-01

The paper presents the results of quantitative analysis of C, Mn, Ni and Cu content on strength and cold-resistance of rolled plates. Relations between the ferritic-bainitic structure morphology and anisotropy and steel performance characteristics have been established. Influence of thermal and deformation rolling patterns on steel structure has been studied. The steel chemical composition has been improved and precision thermomechanical processing conditions for production of cold-resistant Arc-steel plates have been developed.

Irradiation embrittlement of pressure vessel steels

International Nuclear Information System (INIS)

Brumovsky, M.; Vacek, M.

1975-01-01

A Standard Research Programme on Irradiation Embrittlement of Pressure Vessel Steels was approved by the Coordinating Meeting on the 12th May 1972 at the Working Group on Engineering Aspects of Irradiation Embrittlement of Pressure Vessel Steels. This Working Group was set up by the International Atomic Energy Agency in Vienna. Seven countries with their research institutes agreed on doing irradiation experiments according to the approved programme on steel A533 B from the U.S. HSST Programme. The Czechoslovak contribution covering tensile and impact testing of non-irradiated steel and steel irradiated at 280degC to 1.3 x 10 23 n/m 2 (E above 1 MeV) is presented in this report. As an additional part the same set of experiments was carried out on two additional steels - A 542 and A 543, made in SKODA Works for comparison of their irradiation embrittlement and hardening with A533 B steel. (author)

Heissdampfreaktor (HDR) steel-containment-vessel and floodwater-storage-tank structural-dynamics tests

International Nuclear Information System (INIS)

Arendts, J.G.

1982-01-01

Inertance (vibration) testing of two significant vessels at the Heissdampfreaktor (HDR) facility, located near Kahl, West Germany, was recently completed. Transfer functions were obtained for determination of the modal properties (frequencies, mode shapes and damping) of the vessels using two different test methods for comparative purposes. One of the vessels tested was the steel containment vessel (SCV). The SCV is approximately 180 feet high and 65 feet in diameter with a 1.2-inch wall thickness. The other vessel, called the floodwater storage tank (FWST), is a vertically standing vessel approximately 40 feet high and 10 feet in diameter with a 1/2-inch wall thickness. The FWST support skirt is square (in plan views) with its corners intersecting the ellipsoidal bottom head near the knuckle region

Heat treatments in a conventional steel to reproduce the microstructure of a nuclear grade steel

International Nuclear Information System (INIS)

Rosalio G, M.

2014-01-01

The ferritic steels used in the manufacture of pressurized vessels of Boiling Water Reactors (BWR) suffer degradation in their mechanical properties due to damage caused by the neutron fluxes of high energy bigger to a Mega electron volt (E> 1 MeV) generated in the reactor core. The materials with which the pressurized vessels of nuclear reactors cooled by light water are built correspond to low alloy ferritic steels. The effect of neutron irradiation on these steels is manifested as an increase in hardness, mechanical strength, with the consequent decrease in ductility, fracture toughness and an increase in temperature of ductile-brittle transition. The life of a BWR is 40 years, its design must be considered sufficient margin of safety because pressure forces experienced during operation, maintenance and testing of postulated accident conditions. It is necessary that under these conditions the vessel to behave ductile and likely to propagate a fracture is minimized. The vessels of light water nuclear reactors have a bainite microstructure. Specifically, the reactor vessels of the nuclear power plant of Laguna Verde (Veracruz, Mexico) are made of a steel Astm A-533, Grade B Class 1. At present they are carrying out some welding tests for the construction of a model of a BWR, however, to use nuclear grade steel such as Astm A-533 to carry out some of the welding tests, is very expensive; perform these in a conventional material provides basic information. Although the microstructure present in the conventional material does not correspond exactly to the degree of nuclear material, it can take of reference. Therefore, it is proposed to conduct a pilot study to establish the thermal treatment that reproduces the microstructure of nuclear grade steel, in conventional steel. The resulting properties of the conventional steel samples will be compared to a JRQ steel, that is a steel Astm A-533, Grade B Class 1, provided by IAEA. (Author)

Controlling DC permeability in cast steels

Energy Technology Data Exchange (ETDEWEB)

Sumner, Aaran, E-mail: aaran.sumner@nottingham.ac.uk [University of Nottingham, Nottingham University Park Campus, Nottingham NG7 2RD, England (United Kingdom); Gerada, Chris, E-mail: chris.gerada@nottingham.ac.uk [Electrical Machines, University of Nottingham, Tower Building, Nottingham NG7 2RD, England (United Kingdom); Brown, Neil, E-mail: neil.brown@cummins.com [Advanced Electrical Machines Research and Technology at Cummins Power Generation, Peterborough PE2 6FZ, England (United Kingdom); Clare, Adam, E-mail: adam.clare@nottingham.ac.uk [Advanced Manufacturing, University of Nottingham, University Park Campus, Nottingham NG7 2RD, England (United Kingdom)

2017-05-01

Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

Controlling DC permeability in cast steels

International Nuclear Information System (INIS)

Sumner, Aaran; Gerada, Chris; Brown, Neil; Clare, Adam

2017-01-01

Annealing (at multiple cooling rates) and quenching (with tempering) was performed on specimens of cast steel of varying composition. The aim was to devise a method for selecting the steel with the highest permeability, from any given range of steels, and then increasing the permeability by heat treatment. Metallographic samples were imaged using optical microscopy to show the effect of the applied heat treatments on the microstructure. Commonly cast steels can have DC permeability altered by the careful selection of a heat treatment. Increases of up to 381% were achieved by annealing using a cooling rate of 6.0 °C/min. Annealing was found to cause the carbon present in the steel to migrate from grain boundaries and from within ferrite crystals into adjacent pearlite crystals. The migration of the carbon resulted in less carbon at grain boundaries and within ferrite crystals reducing the number of pinning sites between magnetic domains. This gives rise to a higher permeability. Quenching then tempering was found to cause the formation of small ferrite crystals with the carbon content of the steel predominately held in the martensitic crystal structures. The results show that with any given range of steel compositions the highest baseline DC permeability will be found with the steel that has the highest iron content and the lowest carbon content. For the samples tested in this paper a cooling rate of 4.5 °C/min resulted in the relative permeability of the sample with the highest baseline permeability, AS4, increasing from 783 to 1479 at 0.5 T. This paper shows how heat treatments commonly applied to hypoeutectoid cast steels, to improve their mechanical performance, can be used to also enhance electromagnetic properties of these alloys. The use of cast steels allows the creation of DC components for electrical machines not possible by the widely used method of stacking of electrical grade sheet steels. - Highlights: • A range of structural steels had their

STEFINS: a steel freezing integral simulation program

International Nuclear Information System (INIS)

Frank, M.V.

1980-09-01

STEFINS (STEel Freezing INtegral Simulation) is a computer program for the calculation of the rate of solidification of molten steel on solid steel. Such computations arize when investigating core melt accidents in fast reactors. In principle this problem involves a coupled two-dimensional thermal and hydraulic approach. However, by physically reasonable assumptions a decoupled approach has been developed. The transient solidification of molten steel on a cold wall is solved in the direction normal to the molten steel flow and independent from the solution for the molten steel temperature and Nusselt number along the direction of flow. The solutions to the applicable energy equations have been programmed in cylindrical and slab geometries. Internal gamma heating of steel is included

Nitrogen-containing steels and thermomechanical treatment

International Nuclear Information System (INIS)

Kaputkina, L.; Prokoshkina, V.G.; Svyazhin, G.

2004-01-01

The strengthening of nitrogen-containing corrosion-resistant steels resulting from alloying and thermomechanical treatment have been investigated using X-ray diffraction analysis, light microscopy, hardness measurements and tensile testing. Combined data have been obtained for nitrogen interaction with alloying elements , peculiarities of deformed structure and short-range of nitrogen-containing steels of various structural classes. The higher nitrogen and total alloying element contents, the higher deformation strengthening. Prospects of use the steels with not high nitrogen content and methods of their thermomechanical strengthening are shown. High temperature thermomechanical treatment (HTMT) is very effective for obtaining high and thermally stable constructional strength of nitrogen-containing steels of all classes. The HTMT is most effective if used in a combination with dispersion hardening for aging steels or in the case of mechanically unstable austenitic steels. (author)

Automated Steel Cleanliness Analysis Tool (ASCAT)

Energy Technology Data Exchange (ETDEWEB)

Gary Casuccio (RJ Lee Group); Michael Potter (RJ Lee Group); Fred Schwerer (RJ Lee Group); Dr. Richard J. Fruehan (Carnegie Mellon University); Dr. Scott Story (US Steel)

2005-12-30

The objective of this study was to develop the Automated Steel Cleanliness Analysis Tool (ASCATTM) to permit steelmakers to evaluate the quality of the steel through the analysis of individual inclusions. By characterizing individual inclusions, determinations can be made as to the cleanliness of the steel. Understanding the complicating effects of inclusions in the steelmaking process and on the resulting properties of steel allows the steel producer to increase throughput, better control the process, reduce remelts, and improve the quality of the product. The ASCAT (Figure 1) is a steel-smart inclusion analysis tool developed around a customized next-generation computer controlled scanning electron microscopy (NG-CCSEM) hardware platform that permits acquisition of inclusion size and composition data at a rate never before possible in SEM-based instruments. With built-in customized ''intelligent'' software, the inclusion data is automatically sorted into clusters representing different inclusion types to define the characteristics of a particular heat (Figure 2). The ASCAT represents an innovative new tool for the collection of statistically meaningful data on inclusions, and provides a means of understanding the complicated effects of inclusions in the steel making process and on the resulting properties of steel. Research conducted by RJLG with AISI (American Iron and Steel Institute) and SMA (Steel Manufactures of America) members indicates that the ASCAT has application in high-grade bar, sheet, plate, tin products, pipes, SBQ, tire cord, welding rod, and specialty steels and alloys where control of inclusions, whether natural or engineered, are crucial to their specification for a given end-use. Example applications include castability of calcium treated steel; interstitial free (IF) degasser grade slag conditioning practice; tundish clogging and erosion minimization; degasser circulation and optimization; quality assessment/steel

Automated Steel Cleanliness Analysis Tool (ASCAT)

International Nuclear Information System (INIS)

Gary Casuccio; Michael Potter; Fred Schwerer; Richard J. Fruehan; Dr. Scott Story

2005-01-01

The objective of this study was to develop the Automated Steel Cleanliness Analysis Tool (ASCATTM) to permit steelmakers to evaluate the quality of the steel through the analysis of individual inclusions. By characterizing individual inclusions, determinations can be made as to the cleanliness of the steel. Understanding the complicating effects of inclusions in the steelmaking process and on the resulting properties of steel allows the steel producer to increase throughput, better control the process, reduce remelts, and improve the quality of the product. The ASCAT (Figure 1) is a steel-smart inclusion analysis tool developed around a customized next-generation computer controlled scanning electron microscopy (NG-CCSEM) hardware platform that permits acquisition of inclusion size and composition data at a rate never before possible in SEM-based instruments. With built-in customized ''intelligent'' software, the inclusion data is automatically sorted into clusters representing different inclusion types to define the characteristics of a particular heat (Figure 2). The ASCAT represents an innovative new tool for the collection of statistically meaningful data on inclusions, and provides a means of understanding the complicated effects of inclusions in the steel making process and on the resulting properties of steel. Research conducted by RJLG with AISI (American Iron and Steel Institute) and SMA (Steel Manufactures of America) members indicates that the ASCAT has application in high-grade bar, sheet, plate, tin products, pipes, SBQ, tire cord, welding rod, and specialty steels and alloys where control of inclusions, whether natural or engineered, are crucial to their specification for a given end-use. Example applications include castability of calcium treated steel; interstitial free (IF) degasser grade slag conditioning practice; tundish clogging and erosion minimization; degasser circulation and optimization; quality assessment/steel cleanliness; slab, billet

Corrosion of carbon steel and low-alloy steel in diluted seawater containing hydrazine under gamma-rays irradiation

International Nuclear Information System (INIS)

Nakano, Junichi; Yamamoto, Masahiro; Tsukada, Takashi

2014-01-01

Seawater was injected into reactor cores of Units 1, 2, and 3 in the Fukushima Daiichi nuclear power station as an urgent coolant. It is considered that the injected seawater causes corrosion of steels of the reactor pressure vessel and primary containment vessel. To investigate the effects of gamma-rays irradiation on weight loss in carbon steel and low-alloy steel, corrosion tests were performed in diluted seawater at 50°C under gamma-rays irradiation. Specimens were irradiated with dose rates of 4.4 kGy/h and 0.2 kGy/h. To evaluate the effects of hydrazine (N 2 H 4 ) on the reduction of oxygen and hydrogen peroxide, N 2 H 4 was added to the diluted seawater. In the diluted seawater without N 2 H 4 , weight loss in the steels irradiated with 0.2 kGy/h was similar to that in the unirradiated steels, and weight loss in the steels irradiated with 4.4 kGy/h increased to approximate 1.7 times of those in the unirradiated steels. Weight loss in the steels irradiated in the diluted seawater containing N 2 H 4 was similar to that in the diluted seawater without N 2 H 4 . When N 2 was introduced into the gas phase in the flasks during gamma-rays irradiation, weight loss in the steels decreased. (author)

Study on cementitious properties of steel slag

Directory of Open Access Journals (Sweden)

Zhu G.

2013-01-01

Full Text Available The converter steel slag chemical and mineral components in China’s main steel plants have been analysed in the present paper. The electronic microscope, energy spectrum analysis, X-ray diffraction analysis confirmed the main mineral compositions in the converter slag. Converter slag of different components were grounded to obtain a powder with specific surface area over 400m2/kg, making them to take place some part of the cement in the concrete as the admixture and carry out the standard tests. The results indicate that the converter slag can be used as cementitious materials for construction. Furthermore, physical mechanic and durability tests on the concrete that certain amount of cement be substituted by converter steel slag powder from different steel plants are carried out, the results show that the concrete with partial substitution of steel slag powder has the advantages of higher later period strength, better frost resistance, good wear resistance and lower hydration heat, etc. This study can be used as the technical basis for “Steel Slag Powder Used For Cement And Concrete”, “Steel Slag Portland Cement”, “Low Heat Portland Steel Slag Cement”, “Steel Slag Road Cement” in China, as well as a driving force to the works of steel slag utilization with high-value addition, circular economy, energy conservation and discharge reduction in the iron and steel industry.

Modern steels for light automobiles (review)

Science.gov (United States)

Tikhonov, A. K.

1994-10-01

The article considers the directions of work at VAZ together with metallurgists of the CIS for creating highly efficient economically-alloyed and microalloyed steels; highly ductile forged steels with improved corrosion resistance coated with zinc and with good stamping, welding, and painting capacity. Steels are created for petrol tanks with aluminum-zinc coatings instead of lead, and new heat and corrosion-resistant steels are developed for automobile exhaust gas systems.

Inclusion control in high-performance steels

International Nuclear Information System (INIS)

Holappa, L.E.K.; Helle, A.S.

1995-01-01

Progress of clean steel production, fundamentals of oxide and sulphide inclusions as well as inclusion morphology in normal and calcium treated steels are described. Effects of cleanliness and inclusion control on steel properties are discussed. In many damaging constructional and engineering applications the nonmetallic inclusions have a quite decisive role in steel performance. An example of combination of good mechanical properties and superior machinability by applying inclusion control is presented. (author)

Corrosion Damage in Penetration Nozzle and Its Weldment of Reactor Pressure Vessel Head

International Nuclear Information System (INIS)

Lim, Yun Soo; Kim, Joung Soo; Kim, Hong Pyo; Hwang, Seong Sik; Yi, Young Sun; Kim, Dong Jin; Jung, Man Kyo

2003-07-01

The recent status on corrosion damage of reactor vessel head (RVH) penetration nozzles at primary water reactors (PWRs), including control rod drive mechanism (CRDM) and thermocouple nozzles, was investigated. The studies for primary water stress corrosion cracking (PWSCC) characteristics of Alloy 600 and Alloy 182/82 were reviewed and summarized in terms of the crack initiation and crack growth rate. The studies on the boric acid corrosion (BAC) of low alloy steels were also included in this report. PWSCC was found to be the main failure mechanism of RVH CRDM nozzles, which are constituted with Alloy 600 base metal and Alloy 182 weld filler materials. Alloy 600 and Alloy 182/82 are very susceptible to intergranular SCC in the PWR environments. The PWSCC crack initiation and growth features in the fusion zone of Alloy 182/82 were strongly dependant on solidification anisotropy during welding, test temperature, weld heat, mechanical loading, stress relief heat treatment, cold work and so on. BAC of low alloy steels is a wastage phenomenon due to general corrosion occurring on the over-all surface area of material. Systematic studies, concerned with structural integrity of RVH penetration nozzles as well as improvement of PWSCC resistance of nickel-based weld metals in the simulated PWR environment, are needed

Steel fiber reinforced concrete

International Nuclear Information System (INIS)

Baloch, S.U.

2005-01-01

Steel-Fiber Reinforced Concrete is constructed by adding short fibers of small cross-sectional size .to the fresh concrete. These fibers reinforce the concrete in all directions, as they are randomly oriented. The improved mechanical properties of concrete include ductility, impact-resistance, compressive, tensile and flexural strength and abrasion-resistance. These uniqlte properties of the fiber- reinforcement can be exploited to great advantage in concrete structural members containing both conventional bar-reinforcement and steel fibers. The improvements in mechanical properties of cementitious materials resulting from steel-fiber reinforcement depend on the type, geometry, volume fraction and material-properties of fibers, the matrix mix proportions and the fiber-matrix interfacial bond characteristics. Effects of steel fibers on the mechanical properties of concrete have been investigated in this paper through a comprehensive testing-programme, by varying the fiber volume fraction and the aspect-ratio (Lid) of fibers. Significant improvements are observed in compressive, tensile, flexural strength and impact-resistance of concrete, accompanied by marked improvement in ductility. optimum fiber-volume fraction and aspect-ratio of steel fibers is identified. Test results are analyzed in details and relevant conclusions drawn. The research is finally concluded with future research needs. (author)

Head Lice

Science.gov (United States)

... nits. You should also use hot water to wash any bed linens, towels, and clothing recently worn by the person who had head lice. Vacuum anything that can’t be washed, such as the couch, carpets, your child’s car seat, and any stuffed animals. Because head lice ...

Development of nuclear grade stainless steels at KCSSL

International Nuclear Information System (INIS)

Balachandran, G.; Dhere, M.; Mahadik, A.; Hinge, N.M.; Balasubramanian, V.

2011-01-01

Kalyani Carpenter Special Steels Ltd is an alloy steel plant, where a variety of alloy steel grades are produced for automotive, defence, nuclear and aerospace applications. The plant has developed expertise in processing of several alloy steel grades of superior quality that meets stringent specifications. Primary steel is processed through a combination of electric arc furnace, ladle furnace and vacuum degassing where stringent control over dephosphorisation, desulphurization, deoxidation is effected to get a refined high quality steel. The molten steel is cast through continuous casting of slabs or ingot casting. In grades specific to nuclear application, the primary cast products are further subjected to electroslag remelting to achieve further freedom from inclusions and to achieve a favourable solidification grain structure, which ultimately improve the hot workability of the alloy steel. Appropriate choice of slag and operating parameters are needed for realising the required ingot quality. The present study would examine the processing and quality aspects of some important grades of steels used in nuclear industry namely ferritic 9Cr-1Mo steel, martensitic stainless steels 403, 410, precipitation hardenable 17-4 PH stainless steel and austenitic 321, 316LN stainless steel, which were made and supplied for applications to Indian nuclear industry. The expertise developed in processing the steels in terms of melting, heat treatment and their relationship to structural features and mechanical properties would be highlighted. (author)

Fatigue behaviour of friction welded medium carbon steel and austenitic stainless steel dissimilar joints

International Nuclear Information System (INIS)

Paventhan, R.; Lakshminarayanan, P.R.; Balasubramanian, V.

2011-01-01

Research highlights: → Fusion welding of dissimilar metals is a problem due to difference in properties. → Solid state welding process such as friction welding is a solution for the above problem. → Fatigue life of friction welded carbon steel and stainless steel joints are evaluated. → Effect of notch on the fatigue life of friction welded dissimilar joints is reported. → Formation of intermetallic is responsible for reduction in fatigue life of dissimilar joints. -- Abstract: This paper reports the fatigue behaviour of friction welded medium carbon steel-austenitic stainless steel (MCS-ASS) dissimilar joints. Commercial grade medium carbon steel rods of 12 mm diameter and AISI 304 grade austenitic stainless steel rods of 12 mm diameter were used to fabricate the joints. A constant speed, continuous drive friction welding machine was used to fabricate the joints. Fatigue life of the joints was evaluated conducting the experiments using rotary bending fatigue testing machine (R = -1). Applied stress vs. number of cycles to failure (S-N) curve was plotted for unnotched and notched specimens. Basquin constants, fatigue strength, fatigue notch factor and notch sensitivity factor were evaluated for the dissimilar joints. Fatigue strength of the joints is correlated with microstructure, microhardness and tensile properties of the joints.

Life after Steel

Science.gov (United States)

Mangan, Katherine

2013-01-01

Bobby Curran grew up in a working-class neighborhood in Baltimore, finished high school, and followed his grandfather's steel-toed bootprints straight to Sparrows Point, a 3,000-acre sprawl of industry on the Chesapeake Bay. College was not part of the plan. A gritty but well-paying job at the RG Steel plant was Mr. Curran's ticket to a secure…

Development of new high-performance stainless steels

International Nuclear Information System (INIS)

Park, Yong Soo

2002-01-01

This paper focused on high-performance stainless steels and their development status. Effect of nitrogen addition on super-stainless steel was discussed. Research activities at Yonsei University, on austenitic and martensitic high-performance stainless, steels, and the next-generation duplex stainless steels were introduced

Ferritic/martensitic steels: Promises and problems

International Nuclear Information System (INIS)

Klueh, R.L.; Ehrlich, K.; Abe, F.

1992-01-01

Ferritic/martensitic steels are candidate structural materials for fusion reactors because of their higher swelling resistance, higher thermal conductivity, lower thermal expansion, and better liquid-metal compatibility than austenitic steels. Irradiation effects will ultimately determine the applicability of these steels, and the effects of irradiation on microstructure and swelling, and on the tensile, fatigue, and impact properties of the ferritic/martensitic steels are discussed. Most irradiation studies have been carried out in fast reactors, where little transmutation helium forms. Helium has been shown to enhance swelling and affect tensile and fracture behavior, making helium a critical issue, since high helium concentrations will be generated in conjunction with displacement damage in a fusion reactor. These issues are reviewed to evaluate the status of ferritic/martensitic steels and to assess the research required to insure that such steels are viable candidates for fusion applications

Evaluation criteria of structural steel reliability

International Nuclear Information System (INIS)

Zav'yalov, A.S.

1980-01-01

Different low-carbon and medium-carbon structural steels are investigated. It is stated that steel reliability evaluation criteria depend on the fracture mode, steel suffering from the brittle fracture under the influence of the stresses (despite their great variety) arising in articles during the production and operation. Fibrous steel fracture at the given temperature and article thickness says about its high ductility and toughness and brittle fractures are impossible. Brittle fractures take place in case of a crystalline and mixed fracture with a predominant crystalline component. Evaluation methods of article and sample steel structural strength differing greatly from real articles in a thickness (diameter) or used at temperatures higher than possible operation temperatures cannot be reliability evaluation criteria because at a great thickness (diameter) and lower operation temperatures steel fracture and its strain mode can change resulting in a sharp reliability degradation

Development of PWR pressure vessel steels

International Nuclear Information System (INIS)

Druce, S.; Edwards, B.

1982-01-01

Requirements to be met by vessel steels for pressurized water reactors are analyzed. Chemicat composition of low-alloyed steels, mechanical properties of sheets and forgings made of these steels and changes in the composition and properties over the wall thickness of the reactor vessel are presented. Problems of the vessel manufacturing including welding and heat treatment processes of sheets and forgings are considered. Special attention is paid to steel embrittlement during vessel fabrication and operation (radiation embrittlement, thermal embrittlement). The role of non-metal inclusions and their effect on anisotropy of fracture toughness is discussed. Possible developments of vessel steels and procedures for producing reactor vessels are reviewed

Development of PWR pressure vessel steels

Energy Technology Data Exchange (ETDEWEB)

Druce, S.; Edwards, B.

1982-01-01

Requirements to be met by vessel steels for pressurized water reactors are analyzed. Chemicat composition of low-alloyed steels, mechanical properties of sheets and forgings made of these steels and changes in the composition and properties over the wall thickness of the reactor vessel are presented. Problems of the vessel manufacturing including welding and heat treatment processes of sheets and forgings are considered. Special attention is paid to steel embrittlement during vessel fabrication and operation (radiation embrittlement, thermal embrittlement). The role of non-metal inclusions and their effect on anisotropy of fracture toughness is discussed. Possible developments of vessel steels and procedures for producing reactor vessels are reviewed.

Influence of steel-making process and heat-treatment temperature on the fatigue and fracture properties of pressure vessel steels

International Nuclear Information System (INIS)

Koh, S. K.; Na, E. G.; Baek, T. H.; Won, S. Y.; Park, S. J.; Lee, S. W.

2001-01-01

In this paper, high strength pressure vessel steels having the same chemical compositions were manufactured by the two different steel-making processes, such as Vacuum Degassing(VD) and Electro-Slag Remelting(ESR) methods. After the steel-making process, they were normalized at 955 deg. C, quenched at 843 .deg. C, and finally tempered at 550 .deg. C or 450 deg. C, resulting in tempered martensitic microstructures with different yielding strengths depending on the tempering conditions. Low-Cycle Fatigue(LCF) tests, Fatigue Crack Growth Rate(FCGR) tests, and fracture toughness tests were performed to investigate the fatigue and fracture behaviors of the pressure vessel steels. In contrast to very similar monotonic, LCF, and FCGR behaviors between VD and ESR steels, a quite difference was noticed in the fracture toughness. Fracture toughness of ESR steel was higher than that of VD steel, being attributed to the removal of impurities in steel-making process

Radiologic head CT interpretation errors in pediatric abusive and non-abusive head trauma patients

International Nuclear Information System (INIS)

Kralik, Stephen F.; Finke, Whitney; Wu, Isaac C.; Ho, Chang Y.; Hibbard, Roberta A.; Hicks, Ralph A.

2017-01-01

Pediatric head trauma, including abusive head trauma, is a significant cause of morbidity and mortality. The purpose of this research was to identify and evaluate radiologic interpretation errors of head CTs performed on abusive and non-abusive pediatric head trauma patients from a community setting referred for a secondary interpretation at a tertiary pediatric hospital. A retrospective search identified 184 patients <5 years of age with head CT for known or potential head trauma who had a primary interpretation performed at a referring community hospital by a board-certified radiologist. Two board-certified fellowship-trained neuroradiologists at an academic pediatric hospital independently interpreted the head CTs, compared their interpretations to determine inter-reader discrepancy rates, and resolved discrepancies to establish a consensus second interpretation. The primary interpretation was compared to the consensus second interpretation using the RADPEER trademark scoring system to determine the primary interpretation-second interpretation overall and major discrepancy rates. MRI and/or surgical findings were used to validate the primary interpretation or second interpretation when possible. The diagnosis of abusive head trauma was made using clinical and imaging data by a child abuse specialist to separate patients into abusive head trauma and non-abusive head trauma groups. Discrepancy rates were compared for both groups. Lastly, primary interpretations and second interpretations were evaluated for discussion of imaging findings concerning for abusive head trauma. There were statistically significant differences between primary interpretation-second interpretation versus inter-reader overall and major discrepancy rates (28% vs. 6%, P=0.0001; 16% vs. 1%, P=0.0001). There were significant differences in the primary interpretation-second interpretation overall and major discrepancy rates for abusive head trauma patients compared to non-abusive head trauma

Radiologic head CT interpretation errors in pediatric abusive and non-abusive head trauma patients

Energy Technology Data Exchange (ETDEWEB)

Kralik, Stephen F.; Finke, Whitney; Wu, Isaac C.; Ho, Chang Y. [Indiana University School of Medicine, Department of Radiology and Imaging Sciences, Indianapolis, IN (United States); Hibbard, Roberta A.; Hicks, Ralph A. [Indiana University School of Medicine, Department of Pediatrics, Section of Child Protection Programs, Indianapolis, IN (United States)

2017-07-15

Pediatric head trauma, including abusive head trauma, is a significant cause of morbidity and mortality. The purpose of this research was to identify and evaluate radiologic interpretation errors of head CTs performed on abusive and non-abusive pediatric head trauma patients from a community setting referred for a secondary interpretation at a tertiary pediatric hospital. A retrospective search identified 184 patients <5 years of age with head CT for known or potential head trauma who had a primary interpretation performed at a referring community hospital by a board-certified radiologist. Two board-certified fellowship-trained neuroradiologists at an academic pediatric hospital independently interpreted the head CTs, compared their interpretations to determine inter-reader discrepancy rates, and resolved discrepancies to establish a consensus second interpretation. The primary interpretation was compared to the consensus second interpretation using the RADPEER trademark scoring system to determine the primary interpretation-second interpretation overall and major discrepancy rates. MRI and/or surgical findings were used to validate the primary interpretation or second interpretation when possible. The diagnosis of abusive head trauma was made using clinical and imaging data by a child abuse specialist to separate patients into abusive head trauma and non-abusive head trauma groups. Discrepancy rates were compared for both groups. Lastly, primary interpretations and second interpretations were evaluated for discussion of imaging findings concerning for abusive head trauma. There were statistically significant differences between primary interpretation-second interpretation versus inter-reader overall and major discrepancy rates (28% vs. 6%, P=0.0001; 16% vs. 1%, P=0.0001). There were significant differences in the primary interpretation-second interpretation overall and major discrepancy rates for abusive head trauma patients compared to non-abusive head trauma

Development of High Heat Input Welding High Strength Steel Plate for Oil Storage Tank in Xinyu Steel Company

Science.gov (United States)

Zhao, Hemin; Dong, Fujun; Liu, Xiaolin; Xiong, Xiong

This essay introduces the developed high-heat input welding quenched and tempered pressure vessel steel 12MnNiVR for oil storage tank by Xinyu Steel, which passed the review by the Boiler and Pressure Vessel Standards Technical Committee in 2009. The review comments that compared to the domestic and foreign similar steel standard, the key technical index of enterprise standard were in advanced level. After the heat input of 100kJ/cm electro-gas welding, welded points were still with excellent low temperature toughness at -20°C. The steel plate may be constructed for oil storage tank, which has been permitted by thickness range from 10 to 40mm, and design temperature among -20°C-100°C. It studied microstructure genetic effects mechanical properties of the steel. Many production practices indicated that the mechanical properties of products and the steel by stress relief heat treatment of steel were excellent, with pretreatment of hot metal, converter refining, external refining, protective casting, TMCP and heat treatment process measurements. The stability of performance and matured technology of Xinyu Steel support the products could completely service the demand of steel constructed for 10-15 million cubic meters large oil storage tank.

Corrosion behavior of 2205 duplex stainless steel.

Science.gov (United States)

Platt, J A; Guzman, A; Zuccari, A; Thornburg, D W; Rhodes, B F; Oshida, Y; Moore, B K

1997-07-01

The corrosion of 2205 duplex stainless steel was compared with that of AISI type 316L stainless steel. The 2205 stainless steel is a potential orthodontic bracket material with low nickel content (4 to 6 wt%), whereas the 316L stainless steel (nickel content: 10 to 14 wt%) is a currently used bracket material. Both stainless steels were subjected to electrochemical and immersion (crevice) corrosion tests in 37 degrees C, 0.9 wt% sodium chloride solution. Electrochemical testing indicates that 2205 has a longer passivation range than 316L. The corrosion rate of 2205 was 0.416 MPY (milli-inch per year), whereas 316L exhibited 0.647 MPY. When 2205 was coupled to 316L with equal surface area ratio, the corrosion rate of 2205 reduced to 0.260 MPY, indicating that 316L stainless steel behaved like a sacrificial anode. When 316L is coupled with NiTi, TMA, or stainless steel arch wire and was subjected to the immersion corrosion test, it was found that 316L suffered from crevice corrosion. On the other hand, 2205 stainless steel did not show any localized crevice corrosion, although the surface of 2205 was covered with corrosion products, formed when coupled to NiTi and stainless steel wires. This study indicates that considering corrosion resistance, 2205 duplex stainless steel is an improved alternative to 316L for orthodontic bracket fabrication when used in conjunction with titanium, its alloys, or stainless steel arch wires.

ABOUT RATIONING MAXIMUM ALLOWABLE DEFECT DEPTH ON THE SURFACE OF STEEL BILLETS IN PRODUCTION OF HOT-ROLLED STEEL

Directory of Open Access Journals (Sweden)

PARUSOV E. V.

2017-01-01

Full Text Available Formulation of the problem. Significant influence on the quality of rolled steel have various defects on its surface, which in its turn inherited from surface defects of billet and possible damage to the surface of rolled steel in the rolling mill line. One of the criteria for assessing the quality indicators of rolled steel is rationing of surface defects [1; 2; 3; 6; 7]. Current status of the issue. Analyzing the different requirements of regulations to the surface quality of the rolled high-carbon steels, we can conclude that the maximum allowable depth of defects on the surface of billet should be in the range of 2.0...5.0 mm (depending on the section of the billet, method of its production and further the destination Purpose. Develop a methodology for calculating the maximum allowable depth of defects on the steel billet surface depending on the requirements placed on the surface quality of hot-rolled steel. Results. A simplified method of calculation, allowing at the rated depth of defects on the surface of the hot-rolled steel to make operatively calculation of the maximum allowable depth of surface defects of steel billets before heating the metal in the heat deformation was developed. The findings shows that the maximum allowable depth of surface defects is reduced with increasing diameter rolled steel, reducing the initial section steel billet and degrees of oxidation of the metal in the heating furnace.

Non-invasive head fixation for external irradiation of tumors of the head and neck

International Nuclear Information System (INIS)

Bale, R.J.; Sweeney, R.; Nevinny, M.; Auer, T.; Bluhm, A.; Lukas, P.; Vogele, M.; Thumfart, W.F.

1998-01-01

Purpose: To fully utilize the technical capabilities of radiation diagnostics and planning, a precise and reproducible method of head fixation is a prerequisite. Method: We have adapted the Vogele-Bale-Hohner (VBH) head holder (Wellhoefer Dosimetrie, Schwarzenbruck, Germany), originally designed for frameless stereotactic operations, to the requirements of external beam radiotherapy. A precise and reproducible head fixation is attained by an individualized vacuum upper-dental cast which is connected over 2 hydraulic arms to an adjustable head- and rigid base-plate. Radiation field and patient alignment lasers are marked on a relocatable clear PVC localization box. Results: The possibility of craniocaudal adjustment of the head plate on the base plate allows the system to adapt to the actucal position of the patient on the raditherapy couch granting tensionless repositioning. The VBH head holder has proven itself to be a precise yet practicable method of head fixation. Duration of mouthpiece production and daily repositioning is comparable to that of the thermoplastic mask. Conclusion: The new head holder is in routine use at our hospital and quite suitable for external beam radiation of patients with tumors of the head and neck. (orig.) [de

The reactor vessel steels

International Nuclear Information System (INIS)

Bilous, W.; Hajewska, E.; Szteke, W.; Przyborska, M.; Wasiak, J.; Wieczorkowski, M.

2005-01-01

In the paper the fundamental steels using in the construction of pressure vessel water reactor are discussed. The properties of these steels as well as the influence of neutron irradiation on its degradation in the time of exploitation are also done. (authors)

Philippe Lebrun, Head of the AT Department, Lyn Evans, LHC Project Leader, and Lucio Rossi, Head of the AT-MAS Group, in front of the last batch of steel for the LHC at Cockerill Sambre.

CERN Multimedia

2005-01-01

Casting the last batch of steel sheets for the LHC superconducting magnet yokes. The yokes constitute approximately 80% of the accelerator's weight and, if placed side by side, would stretch over 20 km !

Heat Treatment and Properties of Iron and Steel

National Research Council Canada - National Science Library

Digges, Thomas

1966-01-01

.... Chemical compositions, heat treatments, and some properties and uses are presented for structural steels, tool steels, stainless and heat-resisting steels, precipitation-hardenable stainless steels...

Head, Neck, and Oral Cancer

Medline Plus

Full Text Available ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

Computed Tomography (CT) -- Head

Medline Plus

Full Text Available ... Physician Resources Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special x-ray ... What is CT Scanning of the Head? Computed tomography, more commonly known as a CT or CAT ...

Performance Steel Castings

Science.gov (United States)

2012-09-30

system components to be built. Figure la shows the machine design . PSC-2012 Page 94 Glue Application Sheet Transfer Feed Elevator Figure la...Department of Defense such as cleats, ejection chutes , control arms, muzzle brakes, mortar components, clevises, tow bar clamps, ammo conveyor elements...Foundry and the members of Steel Founders’ Society of America. Abstract Weapon system designers and builders need advanced steel casting technology

High temperature oxidation behavior of ODS steels

Science.gov (United States)

Kaito, T.; Narita, T.; Ukai, S.; Matsuda, Y.

2004-08-01

Oxide dispersion strengthened (ODS) steels are being developing for application as advanced fast reactor cladding and fusion blanket materials, in order to allow increased operation temperature. Oxidation testing of ODS steel was conducted under a controlled dry air atmosphere to evaluate the high temperature oxidation behavior. This showed that 9Cr-ODS martensitic steels and 12Cr-ODS ferritic steels have superior high temperature oxidation resistance compared to 11 mass% Cr PNC-FMS and 17 mass% Cr ferritic stainless steel. This high temperature resistance is attributed to earlier formation of the protective α-Cr 2O 3 on the outer surface of ODS steels.

Endovascular Therapy for Management of Oral Hemorrhage in Malignant Head and Neck Tumors

International Nuclear Information System (INIS)

Kakizawa, Hideaki; Toyota, Naoyuki; Naito, Akira; Ito, Katsuhide

2005-01-01

Purpose. To evaluate the efficacy and safety of endovascular therapy in oral hemorrhage from malignant head and neck tumors. Methods. Ten patients (mean age 56 years) with oral hemorrhage caused by malignant head and neck tumors underwent a total of 13 emergency embolization procedures using gelatin sponge particles, steel and/or platinum coils, or a combination of these embolic materials. Angiographic abnormalities, technical success rate, clinical success rate, recurrence rate, complications, hemostatic period, hospital days, survival days, and patient outcome were all analyzed. Results. Angiographic abnormalities were identified during 85% of procedures (11/13). The technical success rate was 100% (13/13 procedures). The primary and secondary clinical success rates were 77% (10/13 procedures) and 67% (2/3 procedures), respectively. The overall clinical success rate was 92%, and the recurrence rate was 22% (2/9 procedures) in patients whom we were able to observe during the 1-month period after embolization. No major complications occurred. Several patients in whom gelatin sponge particles had been used complained of transient local pain after the procedure. The median hemostatic period was 71 days (range 0-518 days). Median hospital and survival days were 59 days (range 3-209 days) and 141 days (range 4-518 days), respectively. Three patients survived and 7 patients died during the observation period. Only 1 of these 7 patients died from hemorrhage. Conclusion. In conclusion, our findings suggest that endovascular therapy is an effective, safe, and repeatable treatment for oral hemorrhage caused by malignant head and neck tumors

Fragmentation of armor piercing steel projectiles upon oblique perforation of steel plates

Directory of Open Access Journals (Sweden)

Aizik F.

2012-08-01

Full Text Available In this study, a constitutive strength and failure model for a steel core of a14.5 mm API projectile was developed. Dynamic response of a projectile steel core was described by the Johnson-Cook constitutive model combined with principal tensile stress spall model. In order to obtain the parameters required for numerical description of projectile core material behavior, a series of planar impact experiments was done. The parameters of the Johnson-Cook constitutive model were extracted by matching simulated and experimental velocity profiles of planar impact. A series of oblique ballistic experiments with x-ray monitoring was carried out to study the effect of obliquity angle and armor steel plate thickness on shattering behavior of the 14.5 mm API projectile. According to analysis of x-ray images the fragmentation level increases with both steel plate thickness and angle of inclination. The numerical modeling of the ballistic experiments was done using commercial finite element code, LS-DYNA. Dynamic response of high hardness (HH armor steel was described using a modified Johnson-Cook strength and failure model. A series of simulations with various values of maximal principal tensile stress was run in order to capture the overall fracture behavior of the projectile’s core. Reasonable agreement between simulated and x-ray failure pattern of projectile core has been observed.

On high temperature strength of carbon steels

International Nuclear Information System (INIS)

Ichinose, Hiroyuki; Tamura, Manabu; Kanero, Takahiro; Ihara, Yoshihito

1977-01-01

In the steels for high temperature use, the oxidation resistance is regarded as important, but carbon steels show enough oxidation resistance to be used continuously at the temperature up to 500 deg. C if the strength is left out of consideration, and up to 450 deg. C even when the strength is taken into account. Moreover, the production is easy, the workability and weldability are good, and the price is cheap in carbon steels as compared with alloy steels. In the boilers for large thermal power stations, 0.15-0.30% C steels are used for reheater tubes, main feed water tubes, steam headers, wall water tubes, economizer tubes, bypass pipings and others, and they account for 70% of all steel materials used for the boilers of 350 MW class and 30% in 1000 MW class. The JIS standard for the carbon steels for high temperature use and the related standards in foreign countries are shown. The high temperature strength of carbon steels changes according to the trace elements, melting and heat treatment as well as the main compositions of C, Si and Mn. Al and N affect the high temperature strength largely. The characteristics of carbon steels after the heating for hours, the factors controlling the microstructure and high temperature strength, and the measures to improve the high temperature strength of carbon steels are explained. (Kako, I.)

East/west steels for reactor pressure vessels

International Nuclear Information System (INIS)

Davies, M.; Kryukov, A.; Nikolaev, Y.; English, C.

1997-01-01

The report consist of three parts dealing with comparison of the irradiation behaviour of 'Eastern' and 'Western' steels, mechanisms of irradiation embrittlement and the role of compositional variations on the irradiation sensitivity of pressure vessels. Nickel, copper and phosphorus are the elements rendering the most essential influence on behaviour of pressure vessel steels under irradiation and subsequent thermal annealing. For WWER-440 reactor pressure vessel (RPV) steels in which nickel content does nor exceed 0.3% the main affecting factors are phosphorous and copper. For WWER-1000 RPV welds in which nickel content generally exceed 1.5% the role of nickel in radiation embrittlement is decisive. In 'Western' type steels main influencing elements are nickel and copper. The secondary role of phosphorus in radiation embrittlement of 'Western' steels is caused by lower relative content compared to 'Eastern' steels. The process of how copper, phosphorus and nickel contents affect the irradiation sensitivity of both types of steel seem to be similar. Some distinctions between the observed radiation effects is apparently caused by differences in the irradiation conditions and ratios of the contents of above mentioned elements in both types of steel. For 'Eastern' RPV steels the dependence of the recovery degree of irradiated steels due to postirradiation thermal annealing id obviously dependent on phosphorus contents and the influence of nickel contents on this process is detectable

Development of ferritic steels for fusion reactor applications

Energy Technology Data Exchange (ETDEWEB)

Klueh, R.L.; Maziasz, P.J.; Corwin, W.R.

1988-08-01

Chromium-molybdenum ferritic (martensitic) steels are leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment will produce long-lived radioactive isotopes that will lead to difficult waste-disposal problems. Such problems could be reduced by replacing the elements in the steels (i.e., Mo, Nb, Ni, N, and Cu) that lead to long-lived radioactive isotopes. We have proposed the development of ferritic steels analogous to conventional Cr-Mo steels, which contain molybdenum and niobium. It is proposed that molybdenum be replaced by tungsten and niobium be replaced by tantalum. Eight experimental steels were produced. Chromium concentrations of 2.25, 5, 9, and 12% were used (all concentrations are in wt %). Steels with these chromium compositions, each containing 2% W and 0.25% V, were produced. To determine the effect of tungsten and vanadium, 2.25 Cr steels were produced with 2% W and no vanadium and with 0.25% V and O and 1% W. A 9Cr steel containing 2% W, 0.25 V, and 0.07% Ta was also studied. For all alloys, carbon was maintained at 0.1%. Tempering studies on the normalized steels indicated that the tempering behavior of the new Cr-W steels was similar to that of the analogous Cr-Mo steels. Microscopy studies indicated that 2% tungsten was required in the 2.25 Cr steels to produce 100% bainite in 15.9-mm-thick plate during normalization. The 5Cr and 9Cr steels were 100% martensite, but the 12 Cr steel contained about 75% martensite with the balance delta-ferrite. 33 refs., 35 figs., 5 tabs.

Development of ferritic steels for fusion reactor applications

International Nuclear Information System (INIS)

Klueh, R.L.; Maziasz, P.J.; Corwin, W.R.

1988-08-01

Chromium-molybdenum ferritic (martensitic) steels are leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment will produce long-lived radioactive isotopes that will lead to difficult waste-disposal problems. Such problems could be reduced by replacing the elements in the steels (i.e., Mo, Nb, Ni, N, and Cu) that lead to long-lived radioactive isotopes. We have proposed the development of ferritic steels analogous to conventional Cr-Mo steels, which contain molybdenum and niobium. It is proposed that molybdenum be replaced by tungsten and niobium be replaced by tantalum. Eight experimental steels were produced. Chromium concentrations of 2.25, 5, 9, and 12% were used (all concentrations are in wt %). Steels with these chromium compositions, each containing 2% W and 0.25% V, were produced. To determine the effect of tungsten and vanadium, 2.25 Cr steels were produced with 2% W and no vanadium and with 0.25% V and O and 1% W. A 9Cr steel containing 2% W, 0.25 V, and 0.07% Ta was also studied. For all alloys, carbon was maintained at 0.1%. Tempering studies on the normalized steels indicated that the tempering behavior of the new Cr-W steels was similar to that of the analogous Cr-Mo steels. Microscopy studies indicated that 2% tungsten was required in the 2.25 Cr steels to produce 100% bainite in 15.9-mm-thick plate during normalization. The 5Cr and 9Cr steels were 100% martensite, but the 12 Cr steel contained about 75% martensite with the balance delta-ferrite. 33 refs., 35 figs., 5 tabs

Hydrogen effects in stainless steel

International Nuclear Information System (INIS)

Caskey, G.R. Jr.

1983-01-01

The effects of hydrogen on stainless steels have been reviewed and are summarized in this paper. Discussion covers hydrogen solution and transport in stainless steels as well as the effects of hydrogen on deformation and fracture under various loading conditions. Damage is caused also by helium that arises from decay of the hydrogen isotope tritium. Austenitic, ferritic, martensite, and precipitation-hardenable stainless steels are included in the discussion. 200 references

Magnetic Resonance Imaging (MRI) -- Head

Science.gov (United States)

... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

Occupational Profiles in the European Steel Industry.

Science.gov (United States)

Franz, Hans-Werner; And Others

The steel industry in Europe has faced great changes, with resulting layoffs and restructuring. Now that the most basic changes seem to be over, it has become evident that the remaining steel industry requires more highly trained workers than was the case previously. Although steel maintenance employees were always highly skilled, steel production…

Cold-formed steel design

CERN Document Server

Yu, Wei-Wen

2010-01-01

The definitive text in the field, thoroughly updated and expanded Hailed by professionals around the world as the definitive text on the subject, Cold-Formed Steel Design is an indispensable resource for all who design for and work with cold-formed steel. No other book provides such exhaustive coverage of both the theory and practice of cold-formed steel construction. Updated and expanded to reflect all the important developments that have occurred in the field over the past decade, this Fourth Edition of the classic text provides you with more of the detailed, up-to-the-minute techni

Performance of Retrofitted Self-Compacting Concrete-Filled Steel Tube Beams Using External Steel Plates

Directory of Open Access Journals (Sweden)

Ahmed A. M. AL-Shaar

2018-01-01

Full Text Available Self-compacting concrete-filled steel tube (SCCFST beams, similar to other structural members, necessitate retrofitting for many causes. However, research on SCCFST beams externally retrofitted by bolted steel plates has seldom been explored in the literature. This paper aims at experimentally investigating the retrofitting performance of square self-compacting concrete-filled steel tube (SCCFST beams using bolted steel plates with three different retrofitting schemes including varied configurations and two different steel plate lengths under flexure. A total of 18 specimens which consist of 12 retrofitted SCCFST beams, three unretrofitted (control SCCFST beams, and three hollow steel tubes were used. The flexural behaviour of the retrofitted SCCFST beams was examined regarding flexural strength, failure modes, and moment versus deflection curves, energy absorption, and ductility. Experimental results revealed that the implemented retrofitting schemes efficiently improve the moment carrying capacity and stiffness of the retrofitted SCCFST beams compared to the control beams. The increment in flexural strength ranged from 1% to 46%. Furthermore, the adopted retrofitting schemes were able to restore the energy absorption and ductility of the damaged beams in the range of 35% to 75% of the original beam ductility. Furthermore, a theoretical model was suggested to predict the moment capacity of the retrofitted SCCFST beams. The theoretical model results were in good agreement with the test results.

ESF GROUND SUPPORT - STRUCTURAL STEEL ANALYSIS

Energy Technology Data Exchange (ETDEWEB)

T. Misiak

1996-06-26

The purpose and objective of this analysis are to expand the level of detail and confirm member sizes for steel sets included in the Ground Support Design Analysis, Reference 5.20. This analysis also provides bounding values and details and defines critical design attributes for alternative configurations of the steel set. One possible configuration for the steel set is presented. This analysis covers the steel set design for the Exploratory Studies Facility (ESF) entire Main Loop 25-foot diameter tunnel.

Ultrasonic extensometry for determining bolt preload in heavy industry - from petrochemical to reactors

International Nuclear Information System (INIS)

Erdman, D.C.

1981-01-01

Use of ultrasonic extensometers has found wide application for bolt preload determination in airborne and aerospace applications where elongation measurement accuracy is often required to .0001 in. Experience has now been gained in heavy industry with fasteners up to 12 feet long, often on studs and bolts with relatively rough head surfaces. Here, accuracy may be reduced to .001 inch, a figure far better than available from torque wrenches. This paper describes some of these heavy industry applications

Reactor head shielding apparatus

International Nuclear Information System (INIS)

Schukei, G.E.; Roebelen, G.J.

1992-01-01

This patent describes a nuclear reactor head shielding apparatus for mounting on spaced reactor head lifting members radially inwardly of the head bolts. It comprises a frame of sections for mounting on the lifting members and extending around the top central area of the head, mounting means for so mounting the frame sections, including downwardly projecting members on the frame sections and complementary upwardly open recessed members for fastening to the lifting members for receiving the downwardly projecting members when the frame sections are lowered thereto with lead shielding supported thereby on means for hanging lead shielding on the frame to minimize radiation exposure or personnel working with the head bolts or in the vicinity thereof

Head, Neck, and Oral Cancer

Science.gov (United States)

... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

Application of the cylindrically guided wave technique for bolt and pump-shaft inspections

International Nuclear Information System (INIS)

Light, G.M.; Ruescher, E.H.; Bloom, E.A.; Tsai, Y.M.

1990-01-01

Southwest Research Institute (SwRI) has been working with the cylindrically guided wave technique (CGWT) since late 1982. The initial work was aimed at inspecting reactor pressure vessel hold-down studs. The CGWT was shown to be able to detect defects as small as 0.060 inch (1.5 mm) deep through metal paths up to 120 inches (304 cm) in stud bolt carbon steel. Later developments in the application of CGWT were aimed at inspecting reactor coolant pump (RCP) shafts. The RCP shafts are usually approximately 2 meters long and have changing diameters along the length, from approximately 12 cm to 23 cm in discrete steps. The pump shafts have been susceptible to small cracks and can be inspected most cost-effectively from the top of the shaft. A matrix transducer composed of six 1-inch (2.54-cm) diameter transducers along with pulsing and receiving electronics (EPRI Pump-Shaft Inspection System) was developed during 1988. A patent application for this technology has been made. This report describes the work conducted during 1989 and the results obtained

Characterization of friction stir welded joint of low nickel austenitic stainless steel and modified ferritic stainless steel

Science.gov (United States)

Mondal, Mounarik; Das, Hrishikesh; Ahn, Eun Yeong; Hong, Sung Tae; Kim, Moon-Jo; Han, Heung Nam; Pal, Tapan Kumar

2017-09-01

Friction stir welding (FSW) of dissimilar stainless steels, low nickel austenitic stainless steel and 409M ferritic stainless steel, is experimentally investigated. Process responses during FSW and the microstructures of the resultant dissimilar joints are evaluated. Material flow in the stir zone is investigated in detail by elemental mapping. Elemental mapping of the dissimilar joints clearly indicates that the material flow pattern during FSW depends on the process parameter combination. Dynamic recrystallization and recovery are also observed in the dissimilar joints. Among the two different stainless steels selected in the present study, the ferritic stainless steels shows more severe dynamic recrystallization, resulting in a very fine microstructure, probably due to the higher stacking fault energy.

Utilization of structural steel in buildings.

Science.gov (United States)

Moynihan, Muiris C; Allwood, Julian M

2014-08-08

Over one-quarter of steel produced annually is used in the construction of buildings. Making this steel causes carbon dioxide emissions, which climate change experts recommend be reduced by half in the next 37 years. One option to achieve this is to design and build more efficiently, still delivering the same service from buildings but using less steel to do so. To estimate how much steel could be saved from this option, 23 steel-framed building designs are studied, sourced from leading UK engineering firms. The utilization of each beam is found and buildings are analysed to find patterns. The results for over 10 000 beams show that average utilization is below 50% of their capacity. The primary reason for this low value is 'rationalization'-providing extra material to reduce labour costs. By designing for minimum material rather than minimum cost, steel use in buildings could be drastically reduced, leading to an equivalent reduction in 'embodied' carbon emissions.

The head-mounted microscope.

Science.gov (United States)

Chen, Ting; Dailey, Seth H; Naze, Sawyer A; Jiang, Jack J

2012-04-01

Microsurgical equipment has greatly advanced since the inception of the microscope into the operating room. These advancements have allowed for superior surgical precision and better post-operative results. This study focuses on the use of the Leica HM500 head-mounted microscope for the operating phonosurgeon. The head-mounted microscope has an optical zoom from 2× to 9× and provides a working distance from 300 mm to 700 mm. The headpiece, with its articulated eyepieces, adjusts easily to head shape and circumference, and offers a focus function, which is either automatic or manually controlled. We performed five microlaryngoscopic operations utilizing the head-mounted microscope with successful results. By creating a more ergonomically favorable operating posture, a surgeon may be able to obtain greater precision and success in phonomicrosurgery. Phonomicrosurgery requires the precise manipulation of long-handled cantilevered instruments through the narrow bore of a laryngoscope. The head-mounted microscope shortens the working distance compared with a stand microscope, thereby increasing arm stability, which may improve surgical precision. Also, the head-mounted design permits flexibility in head position, enabling operator comfort, and delaying musculoskeletal fatigue. A head-mounted microscope decreases the working distance and provides better ergonomics in laryngoscopic microsurgery. These advances provide the potential to promote precision in phonomicrosurgery. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Corrosion fatigue of pressure vessel steels in PWR environments--influence of steel sulfur content

International Nuclear Information System (INIS)

Scott, P.M.; Druce, S.G.; Truswell, A.E.

1984-01-01

Large effects of simulated light water reactor environments at 288 C on fatigue crack growth in low alloy pressure vessel steels are observed only when specific mechanical, metallurgical, and electrochemical conditions are satisfied simultaneously. In this paper, the relative importance of three key variables--steel impurity content, water chemistry, and flow rate--and their interaction with loading rate or strain rate are examined. In particular, the results of a systematic examination of the influence of a steel's sulfur content are described

Corrosion fatigue of pressure vessel steels in PWR environments--influence of steel sulfur content

Energy Technology Data Exchange (ETDEWEB)

Scott, P.M.; Druce, S.G.; Truswell, A.E.

1984-07-01

Large effects of simulated light water reactor environments at 288 C on fatigue crack growth in low alloy pressure vessel steels are observed only when specific mechanical, metallurgical, and electrochemical conditions are satisfied simultaneously. In this paper, the relative importance of three key variables--steel impurity content, water chemistry, and flow rate--and their interaction with loading rate or strain rate are examined. In particular, the results of a systematic examination of the influence of a steel's sulfur content are described.

Heading Frequency Is More Strongly Related to Cognitive Performance Than Unintentional Head Impacts in Amateur Soccer Players.

Science.gov (United States)

Stewart, Walter F; Kim, Namhee; Ifrah, Chloe; Sliwinski, Martin; Zimmerman, Molly E; Kim, Mimi; Lipton, Richard B; Lipton, Michael L

2018-01-01

Compared to heading, unintentional head impacts (e.g., elbow to head, head to head, head to goalpost) in soccer are more strongly related to risk of moderate to very severe Central Nervous System (CNS) symptoms. But, most head impacts associated with CNS symptoms that occur in soccer are mild and are more strongly related to heading. We tested for a differential relation of heading and unintentional head impacts with neuropsychological (NP) test performance. Active adult amateur soccer players were recruited in New York City and the surrounding areas for this repeated measures longitudinal study of individuals who were enrolled if they had 5+ years of soccer play and were active playing soccer 6+ months/year. All participants completed a baseline validated questionnaire ("HeadCount-2w"), reporting 2-week recall of soccer activity, heading and unintentional head impacts. In addition, participants also completed NP tests of verbal learning, verbal memory, psychomotor speed, attention, and working memory. Most participants also completed one or more identical follow-up protocols (i.e., HeadCount-2w and NP tests) at 3- to 6-month intervals over a 2-year period. Repeated measures General Estimating Equations (GEE) linear models were used to determine if variation in NP tests at each visit was related to variation in either heading or unintentional head impacts in the 2-week period before testing. 308 players (78% male) completed 741 HeadCount-2w. Mean (median) heading/2-weeks was 50 (17) for men and 26 (7) for women. Heading was significantly associated with poorer performance on psychomotor speed ( p  impacts were not significantly associated with any NP test. Results did not differ after excluding 22 HeadCount-2w with reported concussive or borderline concussive symptoms. Poorer NP test performance was consistently related to frequent heading during soccer practice and competition in the 2 weeks before testing. In contrast, unintentional head impacts incurred

Aerosol measurements from plasma torch cuts on stainless steel, carbon steel, and aluminum

International Nuclear Information System (INIS)

Novick, V.J.; Brodrick, C.J.; Crawford, S.; Nasiatka, J.; Pierucci, K.; Reyes, V.; Sambrook, J.; Wrobel, S.; Yeary, J.

1996-01-01

The main purpose of this project is to quantify aerosol particle size and generation rates produced by a plasma torch whencutting stainless steel, carbon steel and aluminum. the plasma torch is a common cutting tool used in the dismantling of nuclear facilities. Eventually, other cutting tools will be characterized and the information will be compiled in a user guide to aid in theplanning of both D ampersand D and other cutting operations. The data will be taken from controlled laboratory experiments on uncontaminated metals and field samples taken during D ampersand D operations at ANL nuclear facilities. The plasma torch data was collected from laboratory cutting tests conducted inside of a closed, filtered chamber. The particle size distributions were determined by isokinetically sampling the exhaust duct using a cascade impactor. Cuts on different thicknesses showed there was no observable dependence of the aerosol quantity produced as a function of material thickness for carbon steel. However, data for both stainless steel and aluminum revealed that the aerosol mass produced for these materials appear to have some dependance on thickness, with thinner materials producing tmore aerosols. The results of the laboratory cutting tests show that most measured particle size distributions are bimodal with one mode at about 0.2 μm and the other at about 10 μm. The average Mass Median Aerodynamic Diameters (MMAD's) for these tests are 0.36 ±0.08 μm for stainless steel, 0.48 ±0.17μm for aluminum and 0.52±0.12 μm for carbon steel

Magnetic Resonance Imaging (MRI) -- Head

Medline Plus

Full Text Available ... News Physician Resources Professions Site Index A-Z Magnetic Resonance Imaging (MRI) - Head Magnetic resonance imaging (MRI) of the head uses a powerful ... the Head? What is MRI of the Head? Magnetic resonance imaging (MRI) is a noninvasive medical test that ...

Head, Neck, and Oral Cancer

Medline Plus

Full Text Available ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ... find out more. Oral, Head and Neck Pathology Oral, Head and Neck Pathology Close to 49,750 Americans will be diagnosed ...

Head-positioning scintillation camera and head holder therefor

International Nuclear Information System (INIS)

Kay, T.D.

1976-01-01

A holder for immobilizing the head of a patient undergoing a vertex brain scan by a Gamma Scintillation Camera is described. The holder has a uniquely designed shape capable of comfortably supporting the head. In addition, this holder can be both adjustably and removably utilized in combination with the scintillation camera so as to enable the brain scan operation to take place while the patient is in the seated position

Kawasaki Steel Giho, Vol. 27, No. 4, 1995. Special issue on steel structure

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-31

;Contents (Partial): Vertical Gust Prediction of Cable-Stayed Bridges in Yawed Wind; Design and Construction of a Super Platform Structure Made of Steel; Prefabricated Steel Deck of Battledeck Floor Type for Redecking; Aesthetic Design of Structures; and Lift-up Construction Method for Multi-layer Building.

Data for a steel industry model

OpenAIRE

Mæstad, Ottar

2000-01-01

SNF has recently developed a new model of the steel market and some of the major factor markets connected to the steel industry. The aim of the model has been to study how regulations of the emissions of carbon dioxide (CO2) in the steel industry might affect the structure of the industry. It has also been an objective to investigate how structural changes in the steel industry might influence on the industry’s demand for transport services. This paper outlines the details about the data that...

Transducer-Mounting Fixture

Science.gov (United States)

Spiegel, Kirk W.

1990-01-01

Transducer-mounting fixture holds transducer securely against stud. Projects only slightly beyond stud after installation. Flanged transducer fits into fixture when hinged halves open. When halves reclosed, fixture tightened onto threaded stud until stud makes contact with transducer. Knurled area on fixture aids in tightening fixture on stud.

Symbolic aesthetics in steel structural systems

Directory of Open Access Journals (Sweden)

Usama Abdul-Mun'em Khuraibet

2015-02-01

Full Text Available The aesthetic expression and its orders are important for steel structures forming. Steel structures are a compilation of structural elements, where its shapes have standard dimensions and pre-fabricated. As the steel construction systems not only aim to achieve the functional requirements for users, but must also have the symbolic aesthetics which provides visually and cognitive expression for viewers. In this sense the research interested in expressional aesthetics in these systems and highlights the importance of attention as structural items. Therefore the visual items which related with steel structures contain some of the most powerful forms of modern architecture, steel structures with a glass cladding, agility and accuracy in manufacture of structural elements as visual items, structural interest in the forms of spaces which have long span systems or in high buildings are different forms of expression and influence. So the research focuses on the study of those expressive patterns related with the steel construction properties, including the advantages of these systems at the level of strength and firmness, flexibility and economy as well as aesthetic and expression. Accordingly, the research problem concentrated on educational shortage in the study of the structural steel system aspects concerning constructional characteristic, expressive and aesthetic features, and how to deal with them as a language bearing the symbols and meanings which have clear structural style, because it the best ways to make those systems as communication means with users, by premise that the use of expressional symbol in steel construction increases the aesthetic value. Therefore the research aims to reveal the most structural and expressive patterns by analysis the expressional means and steel structural aesthetics.

Heading Frequency Is More Strongly Related to Cognitive Performance Than Unintentional Head Impacts in Amateur Soccer Players

Directory of Open Access Journals (Sweden)

Walter F. Stewart

2018-04-01

Full Text Available ObjectiveCompared to heading, unintentional head impacts (e.g., elbow to head, head to head, head to goalpost in soccer are more strongly related to risk of moderate to very severe Central Nervous System (CNS symptoms. But, most head impacts associated with CNS symptoms that occur in soccer are mild and are more strongly related to heading. We tested for a differential relation of heading and unintentional head impacts with neuropsychological (NP test performance.MethodActive adult amateur soccer players were recruited in New York City and the surrounding areas for this repeated measures longitudinal study of individuals who were enrolled if they had 5+ years of soccer play and were active playing soccer 6+ months/year. All participants completed a baseline validated questionnaire (“HeadCount-2w”, reporting 2-week recall of soccer activity, heading and unintentional head impacts. In addition, participants also completed NP tests of verbal learning, verbal memory, psychomotor speed, attention, and working memory. Most participants also completed one or more identical follow-up protocols (i.e., HeadCount-2w and NP tests at 3- to 6-month intervals over a 2-year period. Repeated measures General Estimating Equations (GEE linear models were used to determine if variation in NP tests at each visit was related to variation in either heading or unintentional head impacts in the 2-week period before testing.Results308 players (78% male completed 741 HeadCount-2w. Mean (median heading/2-weeks was 50 (17 for men and 26 (7 for women. Heading was significantly associated with poorer performance on psychomotor speed (p < 0.001 and attention (p = 0.02 tasks and was borderline significant with poorer performance on the working memory (p = 0.06 task. Unintentional head impacts were not significantly associated with any NP test. Results did not differ after excluding 22 HeadCount-2w with reported concussive or borderline concussive symptoms

Future directions for ferritic/martensitic steels for nuclear applications

International Nuclear Information System (INIS)

Klueh, R.L.; Swindeman, R.W.

2000-01-01

High-chromium (7-12% Cr) ferritic/martensitic steels are being considered for nuclear applications for both fission and fusion reactors. Conventional 9-12Cr Cr-Mo steels were the first candidates for these applications. For fusion reactors, reduced-activation steels were developed that were patterned on the conventional steels but with molybdenum replaced by tungsten and niobium replaced by tantalum. Both the conventional and reduced-activation steels are considered to have an upper operating temperature limit of about 550degC. For improved reactor efficiency, higher operating temperatures are required. For ferritic/martensitic steels that could meet such requirements, oxide dispersion-strengthened (ODS) steels are being considered. In this paper, the ferritic/martensitic steels that are candidate steels for nuclear applications will be reviewed, the prospect for ODS steel development and the development of steels produced by conventional processes will be discussed. (author)

Stress corrosion cracking of austenitic stainless steels in high temperature water and alternative stainless steel

International Nuclear Information System (INIS)

Yonezawa, T.

2015-01-01

In order to clarify the effect of SFE on SCC resistance of austenitic stainless steels and to develop the alternative material of Type 316LN stainless steel for BWR application, the effect of chemical composition and heat treatment on SFE value and SCCGR in oxygenated high temperature water were studied. The correlation factors between SFE values for 54 heats of materials and their chemical compositions for nickel, molybdenum, chromium, manganese, nitrogen, silicon and carbon were obtained. From these correlation factors, original formulae for SFE values calculation of austenitic stainless steels in the SHTWC, SHTFC and AGG conditions were established. The maximum crack length, average crack length and cracked area of the IGSCC for 33 heats were evaluated as IGSCC resistance in oxygenated high temperature water. The IGSCC resistance of strain hardened nonsensitized austenitic stainless steels in oxygenated high temperature water increases with increasing of nickel contents and SFE values. From this study, it is suggested that the SFE value is a key parameter for the IGSCC resistance of non-sensitized strain hardened austenitic stainless steels. As an alternative material of Type 316LN stainless steel, increased SFE value material, which is high nickel, high chromium, low silicon and low nitrogen material, is recommendable. (author)

National steel tries wheeling

International Nuclear Information System (INIS)

Dudak, J.R.

1992-01-01

In 1989, National Steel felt the need to take the next step to make its Detroit-based division, Great Lakes Steel, more competitive in the world flat-rolled steel market. In 1988, Great Lakes Steel started flowing natural gas through the first fully litigated bypass (Competitive Sourcing Option) of a local distribution company. In 1989, the second connection with the new supply route for gas transportation, Panhandle Eastern had started flowing and the LDC, Michigan Consolidated Gas Co. (MichCon) had pulled out their piping previously serving the plants. Since we had been able to structure a fully reliable supply route, storage and balancing program for gas in the face of such strong opposition by the LDC, the author felt it was time to attack the next singularly sourced major commodity, electricity. Electricity, at this major integrated steel plant, represented approximately 7% of plant cost yearly. Yet being monopolized, Great Lakes Division (GLD) could not multiple source this commodity like it does with its other 93% of costs, except for labor (25% of the 93%). Multiple sourcing is done to bring competitive pressure to suppliers and to diversify supplies and protect plant operation in the event of failure by one supplier. This paper describes National Steel's strategy to reduce the cost of power, at the minimum of capital costs, the most expedient way possible, that does not sacrifice any major long-term potential cost improvements. The results show that competitively priced power is available across the mid-west, at prices well below many state regulated electric utilities, for at least 5 to 15 years, but with major obstacles in obtaining transmission access

Auburn Steel Company radioactive contamination incident

International Nuclear Information System (INIS)

Bradley, F.J.; Cabasino, L.; Kelly, R.; Awai, A.; Kasyk, G.

1986-04-01

On February 21, 1983, workers at the Auburn Steel Company, Auburn, New York discovered that about 120 tons of steel poured that day had become contaminated with 60 Co. In addition to the steel, the air cleaning system and portions of the mill used in casting the steel were contaminated. Approximately 25 curies of 60 Co were involved. Decontamination and disposal of the contamination cost in excess of $2,200,000. This report details the discovery of the contamination, decontamination of the plant and disposal of the contamination

Steeling and Resilience in Art Education

Science.gov (United States)

Heise, Donalyn

2014-01-01

Steel is an incredibly strong alloy of iron and carbon. Due to its incredible strength and durability, this resilient material is commonly used for constructing buildings. The transitive verb "steeling" is defined in Miriam-Webster dictionary as "to fill with resolution or determination, as in, she 'steeled herself to face the…

Development of commercial nitrogen-rich stainless steels

International Nuclear Information System (INIS)

Liljas, M.

1999-01-01

This paper reviews the development of nitrogen alloyed stainless steels. Nitrogen alloying of austenitic stainless steels started at an early stage and was to a large extent caused by nickel shortage. However, direct technical advantages such as increased strength of the nitrogen alloyed steels made them attractive alternatives to the current steels. It was not until the advent of the AOD (argon oxygen decarburisation) process in the late 1960s that nitrogen alloying could be controlled to such accuracy that it became successful commercially on a broader scale. The paper describes production aspects and how nitrogen addition influences microstructure and the resulting properties of austenitic and duplex stainless steels. For austenitic steels there are several reasons for nitrogen alloying. Apart from increasing strength nitrogen also improves structural stability, work hardening and corrosion resistance. For duplex steels nitrogen also has a decisive effect in controlling the microstructure during thermal cycles such as welding. (orig.)

Damascus steels: history, processing, properties and carbon dating

International Nuclear Information System (INIS)

Wadsworth, J.

2007-01-01

In the mid-1970s, a class of steels containing high levels of carbon (∼ 1-2 wt% C) was developed for superplastic characteristics - that is, the ability to plastically deform to an extraordinary degree in tension at intermediate temperatures. Because these steels also had excellent room temperature properties, they were developed for their commercial potential. In the late 1970s, we became aware of the striking compositional similarities between these modern steels and the ancient steels of Damascus. This observation led us to revisit the history and metallurgy of Damascus steels and related steels. The legends and origins of Damascus steel date back to the time of Alexander the Great (323 BC) and the medieval Crusades (11th and 12th century AD), and this material has also been the subject of scrutiny by famous scientist in Europe, including Michael Faraday. Modern attempts to reproduce the legendary surface patterns which famously characterized Damascus steels are described. The extend to which the characteristics of Damascus steels are unusual is discussed. Finally, a program on radiocarbon dating was initiated to directly determine the age of about 50 ancient steels, including a Damascus knife, and the results are summarized. (author)

Designing of the chemical composition of steels basing on the hardenability of constructional steels

International Nuclear Information System (INIS)

Dobrzanski, L.A.; Sitek, W.

2003-01-01

The paper presents the original method of modelling of the relationships between chemical composition of alloy constructional steel and its hardenability, employing neural networks. Basing on the experimental results of the hardenability investigations, which employed Jominy method, the model of the neural networks was developed and fully verified experimentally. The model makes it possible to obtain Jominy hardenability curves basing on the steel chemical composition. The model of neural networks, making it possible to design the steel chemical composition, basing on the known Jominy hardenability curve shape, was developed also and fully verified numerically. (author)

Mechanical properties of irradiated 9Cr-2WVTa steel

International Nuclear Information System (INIS)

Klueh, R.L.; Alexander, D.J.; Rieth, M.

1998-01-01

An Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) steel has excellent strength and impact toughness before and after irradiation in the Fast Flux Test Facility and the High Flux Reactor (HFR). The ductile-brittle transition temperature (DBTT) increased only 32 C after 28 dpa at 365 C in FFTF, compared to a shift of ∼60 C for a 9Cr-2WV steel--the same as the 9Cr-2WVTa steel but without tantalum. This difference occurred despite the two steels having similar tensile but without tantalum. This difference occurred despite the two steels having similar tensile properties before and after irradiation. The 9Cr-2WVTa steel has a smaller prior-austenite grain size, but otherwise microstructures are similar before irradiation and show similar changes during irradiation. The irradiation behavior of the 9Cr-2WVTa steel differs from the 9Cr-2WV steel and other similar steels in two ways: (1) the shift in DBTT of the 9Cr-2WVTa steel irradiated in FFTF does not saturate with fluence by ∼28 dpa, whereas for the 9Cr-2WV steel and most similar steels, saturation occurs at <10 dpa, and (2) the shift in DBTT for 9Cr-2WVTa steel irradiated in FFTF and HFR increased with irradiation temperature, whereas it decreased for the 9Cr-2WV steel, as it does for most similar steels. The improved properties of the 9Cr-2WVTa steel and the differences with other steels were attributed to tantalum in solution

Technical features of steel structure construction by Kawasaki Steel; Kawasaki Seitetsu no kokozo gijutsu no tokucho

Energy Technology Data Exchange (ETDEWEB)

Kaneko, T.; Urata, I.; Okata, S. [Kawasaki Steel Corp., Tokyo (Japan)

1996-03-01

In the steel structure technology of Kawasaki Steel, the joint technique (e.g., welding) is added to them while developing or improving the products that meet the social needs as a material supplier. Moreover, the execution technique that manufactures materials or constructs them as an integrated structure, the structural analysis that conforms to the function and application of a structure, and the design technique on dynamic properties or durability such as earthquake resistance, fatigue, and corrosion resistance are synthetically expanded for engineering. In this paper, a building steel frame, non-residence building, bridge, and harbor structure as steel structure in the building and construction fields were described for each structure genre. The structural technology of a building steel frame is summarized to the products of pillar materials. An earthquake brace, using a dead soft steel, with high earthquake energy absorption capability and a damping wall were also developed. The design and execution technique of a large roof was systematized. The exchange technique of a road bridge RC floor and the technique of an unstiffened suspension bridge for pipeline were developed. A new technique was also developed for a suspension monorail track and offshore structure. 30 refs., 5 figs.

Simple Heat Treatment for Production of Hot-Dip Galvanized Dual Phase Steel Using Si-Al Steels

Science.gov (United States)

Equihua-Guillén, F.; García-Lara, A. M.; Muñíz-Valdes, C. R.; Ortíz-Cuellar, J. C.; Camporredondo-Saucedo, J. E.

2014-01-01

This work presents relevant metallurgical considerations to produce galvanized dual phase steels from low cost aluminum-silicon steels which are produced by continuous strip processing. Two steels with different contents of Si and Al were austenized in the two-phase field ferrite + austenite (α + γ) in a fast manner to obtain dual phase steels, suitable for hot-dip galvanizing process, under typical parameters of continuous annealing processing line. Tensile dual phase properties were obtained from specimens cooled from temperature below Ar3, held during 3 min, intermediate cooling at temperature above Ar1 and quenching in Zn bath at 465 °C. The results have shown typical microstructure and tensile properties of galvanized dual phase steels. Finally, the synergistic effect of aluminum, silicon, and residual chromium on martensite start temperature ( M s), critical cooling rate ( C R), volume fraction of martensite, and tensile properties has been studied.

Corrosion behaviour of laser clad stainless steels

International Nuclear Information System (INIS)

Damborenea, J.J. de; Weerasinghe, V.M.; West, D.R.F.

1993-01-01

The present paper is focussed in the study of the properties of a clad layer of stainless steel on a mild steel. By blowing powder of the alloy into a melt pool generated by a laser of 2 KW, an homogeneous layer of 316 stainless steel can be obtained. Structure, composition and corrosion behaviour are similar to those of a stainless steel in as-received condition. (Author)

Ion-nitriding of austenitic stainless steels

International Nuclear Information System (INIS)

Pacheco, O.; Hertz, D.; Lebrun, J.P.; Michel, H.

1995-01-01

Although ion-nitriding is an extensively industrialized process enabling steel surfaces to be hardened by nitrogen diffusion, with a resulting increase in wear, seizure and fatigue resistance, its direct application to stainless steels, while enhancing their mechanical properties, also causes a marked degradation in their oxidation resistance. However, by adaption of the nitriding process, it is possible to maintain the improved wear resistant properties while retaining the oxidation resistance of the stainless steel. The controlled diffusion permits the growth of a nitrogen supersaturated austenite layer on parts made of stainless steel (AISI 304L and 316L) without chromium nitride precipitation. The diffusion layer remains stable during post heat treatments up to 650 F for 5,000 hrs and maintains a hardness of 900 HV. A very low and stable friction coefficient is achieved which provides good wear resistance against stainless steels under diverse conditions. Electrochemical and chemical tests in various media confirm the preservation of the stainless steel characteristics. An example of the application of this process is the treatment of Reactor Control Rod Cluster Assemblies (RCCAs) for Pressurized Water Nuclear Reactors

High - speed steel for precise cased tools

International Nuclear Information System (INIS)

Karwiarz, J.; Mazur, A.

2001-01-01

The test results of high-vanadium high - speed steel (SWV9) for precise casted tools are presented. The face -milling cutters of NFCa80A type have been tested in industrial operating conditions. An average life - time of SWV9 steel tools was 3-10 times longer compare to the conventional high - speed milling cutters. Metallography of SWB9 precise casted steel revealed beneficial for tool properties distribution of primary vanadium carbides in the steel matrix. Presented results should be a good argument for wide application of high - vanadium high - speed steel for precise casted tools. (author)

GPK heading machine

Energy Technology Data Exchange (ETDEWEB)

Krmasek, J.; Novosad, K.

1981-01-01

This article evaluates performance tests of the Soviet made GPK heading machine carried out in 4 coal mines in Czechoslovakia (Ostrava-Karvina region and Kladno mines). GPK works in coal seams and rocks with compression strength of 40 to 50 MPa. Dimensions of the tunnel are height 1.8 to 3.8 m and width 2.6 to 4.7 m, tunnel gradient plus to minus 10 degrees. GPK weighs 16 t, its conical shaped cutting head equipped with RKS-1 cutting tools is driven by an electric motor with 55 kW capacity. Undercarriage of the GPK, gathering-arm loader, hydraulic system, electric system and dust supression system (water spraying or pneumatic section) are characterized. Specifications of GPK heading machines are compared with PK-3r and F8 heading machines. Reliability, number of failures, dust level, noise, productivity depending on compression strength of rocks, heading rate in coal and in rocks, energy consumption, performance in inclined tunnels, and cutting tool wear are evaluated. Tests show that GPK can be used to drive tunnels in coal with rock constituting up to 50% of the tunnel crosscut, as long as rock compression strength does not exceed 50 MPa. In rocks characterized by higher compression strength cutting tool wear sharply increases. GPK is characterized by higher productivity than that of the PK-3r heading machine. Among the weak points of the GPK are: unsatisfactory reliability and excessive wear of its elements. (4 refs.) (In Czech)

Thermochemical surface engineering of steels

DEFF Research Database (Denmark)

Thermochemical Surface Engineering of Steels provides a comprehensive scientific overview of the principles and different techniques involved in thermochemical surface engineering, including thermodynamics, kinetics principles, process technologies and techniques for enhanced performance of steels...

Representation of heading direction in far and near head space

NARCIS (Netherlands)

Poljac, E.; Berg, A.V. van den

2003-01-01

Manipulation of objects around the head requires an accurate and stable internal representation of their locations in space, also during movements such as that of the eye or head. For far space, the representation of visual stimuli for goal-directed arm movements relies on retinal updating, if eye

Reactor vessel head permanent shield

International Nuclear Information System (INIS)

Hankinson, M.F.; Leduc, R.J.; Richard, J.W.; Malandra, L.J.

1989-01-01

A nuclear reactor is described comprising: a nuclear reactor pressure vessel closure head; control rod drive mechanisms (CRDMs) disposed within the closure head so as to project vertically above the closure head; cooling air baffle means surrounding the control rod drive mechanisms for defining cooling air paths relative to the control rod drive mechanisms; means defined within the periphery of the closure head for accommodating fastening means for securing the closure head to its associated pressure vessel; lifting lugs fixedly secured to the closure head for facilitating lifting and lowering movements of the closure head relative to the pressure vessel; lift rods respectively operatively associated with the plurality of lifting lugs for transmitting load forces, developed during the lifting and lowering movements of the closure head, to the lifting lugs; upstanding radiation shield means interposed between the cooling air baffle means and the periphery of the enclosure head of shielding maintenance personnel operatively working upon the closure head fastening means from the effects of radiation which may emanate from the control rod drive mechanisms and the cooling air baffle means; and connecting systems respectively associated with each one of the lifting lugs and each one of the lifting rods for connecting each one of the lifting rods to a respective one of each one of the lifting lugs, and for simultaneously connecting a lower end portion of the upstanding radiation shield means to each one of the respective lifting lugs

The problems of high-nitrogen steels production

International Nuclear Information System (INIS)

Svyazhin, A.G.; Kaputkina, L.M.; Efimenko, S.P.

1999-01-01

Analysis of existing technologies of high-nitrogen steel production shows that rational nitrogen content in mass production corresponds to moderate high values. Such steels can be smelted under normal or slightly elevated pressure in steelmaking units, using processes of mass- and special metallurgy. High-nitrogen steels with ''overequilibrium'' nitrogen content are promising, but technology and equipment for production of them are complicated, and production of such steels is therefore limited. (orig.)

Behaviour of steels in natural environments: focus on stainless steels in natural sea water

International Nuclear Information System (INIS)

Feron, D.

2005-01-01

Corrosion behaviour of steels and alloys in natural environments is not only dependent to material parameters and environmental chemistry, but also to micro-organisms which may be there. The global approach used to investigate the behaviour of alloys in natural environments is illustrated by the work done on stainless steels in seawater. In aerated seawater, studies led to the proposal of an 'enzymatic model' based on the enzymatic catalyze of the cathodic reaction and which allows reproducing the electrochemical behaviour of stainless steels in natural seawater and the crevice corrosion phenomena observed in natural sea waters. Coupling areas under aerobic and anaerobic conditions leads to the worst situation for stainless steel behaviour: the catalysis of the cathodic reaction on aerobic exposed surfaces and the decrease of the corrosion resistance of anaerobic surfaces due to sulphides. These results lead to the concept of electro-active bio-films. (author)

Structure of three Zlatoust bulats (Damascus-steel blades)

Science.gov (United States)

Schastlivtsev, V. M.; Gerasimov, V. Yu.; Rodionov, D. P.

2008-08-01

Chemical composition, structure, and hardness of samples of three Zlatoust bulats (Damascus steels), namely, an Anosov bulat blade (1841), Obukhov bulat blade (1859), and a Shvetsov forged bulat-steel blank (crucible steel) have been investigated. The Anosov bulat possesses all signs of the classical Damascus steel; this is a hypereutectoid carbon steel with a structure formed from chains of carbides against the background of fine pearlite (troostite). A banded pattern is revealed on the surface of the blade. The Obukhov blade cannot be referred to classical Damascus steel. The pattern on the surface of the blade is absent, despite the fact that the initial steel is hypereutectoid. The structure of the blade does not correspond to the structure of classical Damascus steel; this is bainite with numerous cementite particles. The Shvetsov sample cannot be regarded as Damascus steel since it is made from a hypereutectoid steel alloyed by managanese and tungsten. The pattern on the surface of the metal is a consequence of the dendritic structure of the ingot which is developed during forging. The structure of this pattern differs from classical damascene pattern, since the latter is formed due to a specific arrangement of a variety of carbide particles against the pearlitic or some other background obtained during heat treatment.

Cold formability of steels

International Nuclear Information System (INIS)

Lafond, G.; Leclerq, G.; Moliexe, F.; Namdar, R.; Roesch, L.; Sanz, G.

1977-01-01

This work was essentially aimed to the study of the following three questions. Is it possible to assess the cold formability of steels using simple material properties as criteria. What values of mechanical properties can one expect to reach in cold formed parts. Are there simple ways of characterizing the speroidization treatments carried out on steels before cold forming operations. The present report describes the results obtained during this investigation. It is logically divided into three separate parts. Experimental study of cold formability in wire drawing. Influence of metallurgical variables on mechanical properties of high carbon cold drawn wires. Contribution to the study of characterization methods of cold forming steels subjected to a spheroidization heat treatment

Axis of eye rotation changes with head-pitch orientation during head impulses about earth-vertical.

Science.gov (United States)

Migliaccio, Americo A; Schubert, Michael C; Clendaniel, Richard A; Carey, John P; Della Santina, Charles C; Minor, Lloyd B; Zee, David S

2006-06-01

The goal of this study was to assess how the axis of head rotation, Listing's law, and eye position influence the axis of eye rotation during brief, rapid head rotations. We specifically asked how the axis of eye rotation during the initial angular vestibuloocular reflex (VOR) changed when the pitch orientation of the head relative to Earth-vertical was varied, but the initial position of the eye in the orbit and the orientation of Listing's plane with respect to the head were fixed. We measured three-dimensional eye and head rotation axes in eight normal humans using the search coil technique during head-and-trunk (whole-body) and head-on-trunk (head-only) "impulses" about an Earth-vertical axis. The head was initially oriented at one of five pitch angles (30 degrees nose down, 15 degrees nose down, 0 degrees, 15 degrees nose up, 30 degrees nose up). The fixation target was always aligned with the nasooccipital axis. Whole-body impulses were passive, unpredictable, manual, rotations with peak-amplitude of approximately 20 degrees , peak-velocity of approximately 80 degrees /s, and peak-acceleration of approximately 1000 degrees /s2. Head-only impulses were also passive, unpredictable, manual, rotations with peak-amplitude of approximately 20 degrees , peak-velocity of approximately 150 degrees /s, and peak-acceleration of approximately 3000 degrees /s2. During whole-body impulses, the axis of eye rotation tilted in the same direction, and by an amount proportional (0.51 +/- 0.09), to the starting pitch head orientation (P rotation could be predicted from vectorial summation of the gains (eye velocity/head velocity) obtained for rotations about the pure yaw and roll head axes. Thus, even when the orientation of Listing's plane and eye position in the orbit are fixed, the axis of eye rotation during the VOR reflects a compromise between the requirements of Listing's law and a perfectly compensatory VOR.

High yttria ferritic ODS steels through powder forging

Science.gov (United States)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-05-01

Oxide dispersion strengthened (ODS) steels are being developed for future nuclear reactors. ODS Fe-18%Cr-2%W-0.2%Ti steels with 0, 0.35, 0.5, 1 and 1.5% Y2O3 (all compositions in weight%) dispersion were fabricated by mechanical alloying of elemental powders. The powders were placed in a mild steel can and forged in a stream of hydrogen gas at 1473 K. The steels were forged again to final density. The strength of ODS steel increased with yttria content. Though this was accompanied by a decrease in tensile elongation, all the steels showed significant ductility. The ductility in high yttria alloys may be attributed to improved inter-particle bonding between milled powders due to reduction of surface oxides by hydrogen. This may permit development of ODS steels with yttria contents higher than the conventional limit of 0.5%. It is suggested that powder forging is a promising route to fabricate ODS steels with high yttria contents and improved ductility.

Behaviour of carbon steel and chromium steels in CO2 environments

International Nuclear Information System (INIS)

Lefebvre, B.; Bounie, P.; Guntz, G.; Prouheze, J.C.; Renault, J.J.

1984-01-01

The behavior in aqueous CO 2 environments of steel with chromium content between 0 and 22% has been studied by autoclave tests. The influence of chromium and molybdenum contents has been investigated particularly on 13 Cr steel. Conventional electrochemical test results are related to the CO 2 autoclave test results. The influence of the environment: temperature, chloride concentration, partial pressure of CO 2 and some amount of H 2 S on the corrosion resistance are discussed

Microstructural Development during Welding of TRIP steels

NARCIS (Netherlands)

Amirthalingam, M.

2010-01-01

The Advanced High Strength Steels (AHSS) are promising solutions for the production of lighter automobiles which reduce fuel consumption and increase passenger safety by improving crash-worthiness. Transformation Induced Plasticity Steel (TRIP) are part of the advanced high strength steels which

Tribological Response of Heat Treated AISI 52100 Steels Against Steel and Ceramic Counterparts

Directory of Open Access Journals (Sweden)

Türedi E.

2017-09-01

Full Text Available AISI 52100 bearing steels are commonly used in applications requiring high hardness and abrasion resistance. The bearing steels are working under dynamic loads in service conditions and their toughness properties become important. In order to provide the desired mechanical properties, various heat treatments (austenizing, quenching and tempering are usually applied. In this study, AISI 52100 bearing steel samples were austenized at 900°C for ½ h and water quenched to room temperature. Then tempering was carried out at 795°C, 400°C and 200°C for ½ h. In order to investigate the effect of heat treatment conditions on wear behavior, dry friction tests were performed according to ASTM G99-05 Standard with a ‘ball-on-disk’ type tribometer. The samples were tested against steel and ceramic counterparts using the parameters of 100 m distance and 30 N load and 0.063 m/s rotational speed. After wear test, the surface characterization was carried out using microscopy. Wear loss values were calculated using a novel optical method on both flat and counterpart specimens.

Precaution against radioactive contamination of steel products in Germany

International Nuclear Information System (INIS)

Ewers, E.; Schulz-Klemp, V.; Steffen, R.

1999-01-01

Regulations for handling of radioactive materials in Germany. Engagement of the Germany Iron and Steel Institute (VDEh) since the end of the eighties and measures taken. Level of radioactivity in uncontaminated steel products. Agreements between steel industry and scrap supplying industry as well as terms of delivery. Actual status of equipment for detection of radioactivity in the German steel plants. Demands of steel users for clean steel. (author)

Anodized Steel Electrodes for Supercapacitors.

Science.gov (United States)

Sagu, Jagdeep S; Wijayantha, K G Upul; Bohm, Mallika; Bohm, Siva; Kumar Rout, Tapan

2016-03-09

Steel was anodized in 10 M NaOH to enhance its surface texture and internal surface area for application as an electrode in supercapacitors. A mechanism was proposed for the anodization process. Field-emission gun scanning electron microscopy (FEGSEM) studies of anodized steel revealed that it contains a highly porous sponge like structure ideal for supercapacitor electrodes. X-ray photoelectron spectroscopy (XPS) measurements showed that the surface of the anodized steel was Fe2O3, whereas X-ray diffraction (XRD) measurements indicated that the bulk remained as metallic Fe. The supercapacitor performance of the anodized steel was tested in 1 M NaOH and a capacitance of 18 mF cm(-2) was obtained. Cyclic voltammetry measurements showed that there was a large psueudocapacitive contribution which was due to oxidation of Fe to Fe(OH)2 and then further oxidation to FeOOH, and the respective reduction of these species back to metallic Fe. These redox processes were found to be remarkably reversible as the electrode showed no loss in capacitance after 10000 cycles. The results demonstrate that anodization of steel is a suitable method to produce high-surface-area electrodes for supercapacitors with excellent cycling lifetime.

Corrosion of steel in concrete

International Nuclear Information System (INIS)

Preece, C.M.

1982-10-01

A comparative study has been made of those properties of Massiv and Standard cements which are considered to determine their ability to protect steel reinforcement from corroding. Saturated Massiv cement has a higher evaporabel water content, but a significantly finer pore structure than has saturated Standard cement. This fine structure resulted in an electrical resistivity ten times higher and chloride diffusivity ten times lower than those of Standard cement. Electrochemical measurements have shown that the passive current density of steel in Massiv mortar is higher than that of steel in Standard mortar, but the higher current should lead to a more rapid decrease in potential to a level at which neither chloride attack of hydrogen evolution will occur. Whereas steel in Standard mortar was found to be highly susceptible to crevice corrosion, no such attack has been observed in Massiv mortar. Moreover, the initiation of chloride induced corrosion and the subsequent rates of corrosion were both lower in Massiv mortar than in Standard mortar. Thus, it may be predicted that Massiv cement would provide greater protection for steel reinforcement in underground structures exposed to chloride containing ground water than would Standard cement. (author)

46 CFR 56.60-5 - Steel (High temperature applications).

Science.gov (United States)

2010-10-01

....A.) Upon prolonged exposure to temperatures above 775 °F (412 °C), the carbide phase of plain carbon steel, plain nickel-alloy steel, carbon-manganese-alloy steel, manganese-vanadium-alloy steel, and carbon-silicon steel may convert to graphite. (b) (Reproduces 124.2.B.) Upon prolonged exposure to...

Austenitic stainless steels with cryogenic resistance

International Nuclear Information System (INIS)

Tarata, Daniela Florentina

1999-01-01

The most used austenitic stainless steels are alloyed with chromium and nickel and have a reduced carbon content, usually lower than 0.1 % what ensures corresponding properties for processing by plastic deformation at welding, corrosion resistance in aggressive environment and toughness at low temperatures. Steels of this kind alloyed with manganese are also used to reduce the nickel content. By alloying with manganese which is a gammageneous element one ensures the stability of austenites. Being cheaper these steels may be used extensively for components and equipment used in cryogenics field. The best results were obtained with steels of second group, AMnNi, in which the designed chemical composition was achieved, i.e. the partial replacement of nickel by manganese ensured the toughness at cryogenic temperatures. If these steels are supplementary alloyed, their strength properties may increase to the detriment of plasticity and toughness, although the cryogenic character is preserved

Micropurity in stainless steel making

International Nuclear Information System (INIS)

Motloch, Z.

1981-01-01

New technologies were developed by the Vitkovice research institutes in response to high requirements for the quality of high-alloy steels for nuclear power, viz., duplex technology with double vacuum degassing at the DH unit and oxidation vacuum degassing using the VAKUVIT equipment. The steel produced shows low contents of impurities and high micropurity. A study was conducted into changes in carbon content and the formation of titanium nitrides and carbonitrides in austenitic steels during their production, and optimum technological parameters were found for eliminating their formation in forgings. (author)

Water requirements of the iron and steel industry

Science.gov (United States)

Walling, Faulkner B.; Otts, Louis Ethelbert

1967-01-01

Twenty-nine steel plants surveyed during 1957 and 1958 withdrew from various sources about 1,400 billion gallons of water annually and produced 40.8 million tons of ingot steel. This is equivalent to about 34,000 gallons of water per ton of steel. Fifteen iron ore mines and fifteen ore concentration plants together withdrew annually about 89,000 million gallons to produce 15 million tons of iron ore concentrate, or 5,900 gallons per ton of concentrate. About 97 percent of the water used in the steel plants came from surface sources, 2.2 percent was reclaimed sewage, and 1.2 percent was ground water. Steel plants supplied about 96 percent of their own water requirements, although only three plants used self-supplied water exclusively. Water used by the iron ore mines and concentration plants was also predominantly self supplied from surface source. Water use in the iron and steel industry varied widely and depended on the availability of water, age and condition of plants and equipment, kinds of processes, and plant operating procedures. Gross water use in integrated steel plants ranged from 11,200 to 110,000 gallons per ton of steel ingots, and in steel processing plants it ranged from 4,180 to 26,700 gallons per ton. Water reuse also varied widely from 0 to 18 times in integrated steel plants and from 0 to 44 times in steel processing plants. Availability of water seemed to be the principal factor in determining the rate of reuse. Of the units within steel plants, a typical (median) blast furnace required 20,500 gallons of water per ton of pig iron. At the 1956-60 average rate of pig iron consumption, this amounts to about 13,000 gallons per ton of steel ingots or about 40 percent of that required by a typical integrated steel plant 33,200 gallons per ton. Different processes of iron ore concentration are devised specifically for the various kinds of ore. These processes result in a wide range of water use from 124 to 11,300 gallons of water per ton of iron ore

Spark Plasma Co-Sintering of Mechanically Milled Tool Steel and High Speed Steel Powders.

Science.gov (United States)

Pellizzari, Massimo; Fedrizzi, Anna; Zadra, Mario

2016-06-16

Hot work tool steel (AISI H13) and high speed steel (AISI M3:2) powders were successfully co-sintered to produce hybrid tool steels that have properties and microstructures that can be modulated for specific applications. To promote co-sintering, which is made difficult by the various densification kinetics of the two steels, the particle sizes and structures were refined by mechanical milling (MM). Near full density samples (>99.5%) showing very fine and homogeneous microstructure were obtained using spark plasma sintering (SPS). The density of the blends (20, 40, 60, 80 wt % H13) was in agreement with the linear rule of mixtures. Their hardness showed a positive deviation, which could be ascribed to the strengthening effect of the secondary particles altering the stress distribution during indentation. A toughening of the M3:2-rich blends could be explained in view of the crack deviation and crack arrest exerted by the H13 particles.

Spark Plasma Co-Sintering of Mechanically Milled Tool Steel and High Speed Steel Powders

Directory of Open Access Journals (Sweden)

Massimo Pellizzari

2016-06-01

Full Text Available Hot work tool steel (AISI H13 and high speed steel (AISI M3:2 powders were successfully co-sintered to produce hybrid tool steels that have properties and microstructures that can be modulated for specific applications. To promote co-sintering, which is made difficult by the various densification kinetics of the two steels, the particle sizes and structures were refined by mechanical milling (MM. Near full density samples (>99.5% showing very fine and homogeneous microstructure were obtained using spark plasma sintering (SPS. The density of the blends (20, 40, 60, 80 wt % H13 was in agreement with the linear rule of mixtures. Their hardness showed a positive deviation, which could be ascribed to the strengthening effect of the secondary particles altering the stress distribution during indentation. A toughening of the M3:2-rich blends could be explained in view of the crack deviation and crack arrest exerted by the H13 particles.

Metadynamic recrystallization in C steels

Indian Academy of Sciences (India)

Unknown

EN24 and EN2 steels, a drop from 4000 s to 6 s for similar temperature rise was observed. Metadynamic ... carbon–manganese or silicon–manganese steels, but stops after a reduction at ... growth by strain-induced grain boundary migration;.

A Tale of Wootz Steel

Indian Academy of Sciences (India)

manufacture of steel in south India by a crucible process at ... indicates that the production of wootz steel was almost on an industrial scale in ... in an Age of Design marked by ... The Russian Anasoff also studied the process of manufacturing.

Fabrication and characterization of DLC coated microdimples on hip prosthesis heads.

Science.gov (United States)

Choudhury, Dipankar; Ay Ching, Hee; Mamat, Azuddin Bin; Cizek, Jan; Abu Osman, Noor Azuan; Vrbka, Martin; Hartl, Martin; Krupka, Ivan

2015-07-01

Diamond like carbon (DLC) is applied as a thin film onto substrates to obtain desired surface properties such as increased hardness and corrosion resistance, and decreased friction and wear rate. Microdimple is an advanced surface modification technique enhancing the tribological performance. In this study, DLC coated microdimples were fabricated on hip prosthesis heads and their mechanical, material and surface properties were characterized. An Electro discharge machining (EDM) oriented microdrilling was utilized to fabricate a defined microdimple array (diameter of 300 µm, depth of 70 µm, and pitch of 900 µm) on stainless steel (SS) hip prosthesis heads. The dimpled surfaces were then coated by hydrogenated amorphous carbon (a-C:H) and tetrahedral amorphous carbon (Ta-C) layers by using a magnetron sputtering technology. A preliminary tribology test was conducted on these fabricated surfaces against a ceramic ball in simulated hip joint conditions. It was found that the fabricated dimples were perpendicular to the spherical surfaces and no cutting-tools wear debris was detected inside the individual dimples. The a-C:H and Ta-C coatings increased the hardness at both the dimple edges and the nondimpled region. The tribology test showed a significant reduction in friction coefficient for coated surfaces regardless of microdimple arrays: the lowest friction coefficient was found for the a-C:H samples (µ = 0.084), followed by Ta-C (µ = 0.119), as compared to the SS surface (µ = 0.248). © 2014 Wiley Periodicals, Inc.

Carneiro hidráulico com tubulação de alimentação em aço galvanizado e em PVC Hydraulic ram pump perfomance with PVC and steel pipes

Directory of Open Access Journals (Sweden)

Caroline Abate

2002-03-01

Full Text Available A recente crise da energia convencional tem ocasionado a exploração de fontes alternativas de energia. O bombeamento de água utilizando carneiro hidráulico é amplamente empregado em propriedades onde a energia elétrica é escassa ou inexistente. Procurando dar subsídios técnicos para a utilização do PVC nos sistemas de alimentação de um carneiro hidráulico, foi desenvolvido um experimento com objetivo de avaliar o desempenho de um carneiro hidráulico quando alimentado por uma tubulação de PVC e outra de aço galvanizado, sob três alturas de queda (2,1, 3,8 e 4,7 m. Foi utilizada a equação de D'Aubussion's para a avaliação do rendimento, calculado a partir de leituras de altura de recalque, vazão de escape, vazão de recalque e altura de alimentação. Pode-se conseguir o máximo rendimento com o carneiro hidráulico utilizando-se de tubulação de PVC com até 4,2 m de desnível; além desse valor a tubulação de aço galvanizado é mais eficiente.The recent conventional energy crisis is leading to the exploration of alternative energy sources. The pumping of water using ram pumps is widely used in farms where electric energy is scarce or inexistent. This experiment was carried out to evaluate the performance of an hydraulic ram pump utilizing two kinds of supply pipes (PVC and steel using three different supply heads (2.1, 3.8 and 4.7. Delivery head, delivery discharge, waste discharge and supply head were utilized to calculate the yield of the hydraulic ram by the equation of D'Aubussion. The maximum yield of the hydraulic ram was obtained for the PVC pipe for the 4.2 m head; for heads higher than 4.2 m the steel pipe was more efficient.

Head trauma and CT with special reference to diagnosis of complications of head trauma

International Nuclear Information System (INIS)

Samejima, Kanji; Yoshii, Nobuo; Tobari, Chitose

1979-01-01

Cases in which CT was useful for the diagnosis of complications of head trauma were reported. First, complications of head trauma were given an outline, and then, cases of protrusion of the brain, traumatic pneumocephalus, and cerebro-vascular disorders caused by head trauma were mentioned. (Tsunoda, M.)

Optimum conditions for aging of stainless maraging steels

International Nuclear Information System (INIS)

Mironenko, P.A.; Krasnikova, S.I.; Drobot, A.V.

1980-01-01

Aging kinetics of two 0Kh11N10M2T type steels in which 3 % Mo (steel 1), and 3 % Mo and 11 % Co (steel 2) had been additionally introduced instead of titanium were investigated. Electron microscopy and X-ray methods were used. It was ascertained that the process of steel aging proceeded in 3 stages. Steel 2 was hardened more intensively during the aging, had a higher degree of hardness and strength after the aging, weakened more slowly if overaged than steel 1. The intermetallide hcp-phase Fe 2 Mo was the hardening phase on steels extended aging. Optimum combination of impact strength and strength was was achieved using two-stage aging: the first stage - maximum strength aging was achieved, the second stage - aging at minimum temperatures of two-phase α+γ region

An Experimental Study on the Shear Hysteresis and Energy Dissipation of the Steel Frame with a Trapezoidal-Corrugated Steel Plate.

Science.gov (United States)

Shon, Sudeok; Yoo, Mina; Lee, Seungjae

2017-03-06

The steel frame reinforced with steel shear wall is a lateral load resisting system and has higher strength and shear performance than the concrete shear wall system. Especially, using corrugated steel plates in these shear wall systems improves out-of-plane stiffness and flexibility in the deformation along the corrugation. In this paper, a cyclic loading test of this steel frame reinforced with trapezoidal-corrugated steel plate was performed to evaluate the structural performance. The hysteresis behavior and the energy dissipation capacity of the steel frame were also compared according to the corrugated direction of the plate. For the test, one simple frame model without the wall and two frame models reinforced with the plate are considered and designed. The test results showed that the model reinforced with the corrugated steel plate had a greater accumulated energy dissipation capacity than the experimental result of the non-reinforced model. Furthermore, the energy dissipation curves of two reinforced frame models, which have different corrugated directions, produced similar results.

Radiation induced microstructural evolution in ferritic/martensitic steels

International Nuclear Information System (INIS)

Kohno, Y.; Kohyama, A.; Asakura, K.; Gelles, D.S.

1993-01-01

R and D of ferritic/martensitic steels as structural materials for fusion reactor is one of the most important issues of fusion technology. The efforts to characterize microstructural evolution under irradiation in the conventional Fe-Cr-Mo steels as well as newly developed Fe-Cr-Mn or Fe-Cr-W low activation ferritic/ martensitic steels have been continued. This paper provides some of the recent results of heavy irradiation effects on the microstructural evolution of ferritic/martensitic steels neutron irradiated in the FFTF/MOTA (Fast Flux Test Facility/Materials Open Test Assembly). Materials examined are Fe-10Cr-2Mo dual phase steel (JFMS: Japanese Ferritic/Martensitic Steel), Fe-12Cr-XMn-1Mo manganese stabilized martensitic steels and Fe-8Cr-2W Tungsten stabilized low activation martensitic steel (F82H). JFMS showed excellent void swelling resistance similar to 12Cr martensitic steel such as HT-9, while the manganese stabilized steels and F82H showed less void swelling resistance with small amount of void swelling at 640-700 K (F82H: 0.14% at 678 K). As for irradiation response of precipitate behavior, significant formation of intermetallic χ phase was observed in the manganese stabilized steels along grain boundaries which is though to cause mechanical property degradation. On the other hand, precipitates identified were the same type as those in unirradiated condition in F82H with no recognition of irradiation induced precipitates, which suggested satisfactory mechanical properties of F82H after the irradiation. (author)

Stress-assisted, microbial-induced corrosion of stainless steel primary piping and other aging issues at the Omega West Reactor

International Nuclear Information System (INIS)

Andrade, A.

1995-01-01

After the discovery of cooling system leak of about 284 liters per twenty-four (24) hour period, an investigation determined that the 76.2-cm diameter, 33.5-m long stainless-steel (304) OWR delay line was losing water at the same nominal rate. An excavation effort revealed that a circumferential crack, approximately 0.0025 cm in width, extended around the bottom half of the delay line. In addition, other evidence of what appeared to be microcracking and pitting that originated at random nucleated sites around the pipe were also found. Results of destructive analysis and nondestructive testing allowed Los Alamos staff to conclude that the direct cause for the main crack and other pitting resulted from stress-assisted, microbial-induced corrosion of the stainless steel primary piping. The results also indicated that microbial action from bacteria that are normally present in earth can be extremely harmful to stainless- steel piping under certain conditions. Other potential problems that could have also eventually led to a permanent shutdown of the OWR were discussed. These problems, although never encountered nor associated with the current shutdown, were identified in aging studies and are associated with: (1) the water-cooled, bismuth gamma-ray shield and, (2) the aluminum thermal column head seal that prevents reactor vessel water from entering into the graphite-filled thermal column

Corrosion fatigue crack growth in clad low-alloy steels: Part 1, medium-sulfur forging steel

International Nuclear Information System (INIS)

James, L.A.; Poskie, T.J.; Auten, T.A.; Cullen, W.H.

1996-01-01

Corrosion fatigue crack propagation tests were conducted on a medium- sulfur ASTM A508-2 forging steel overlaid with weld-deposited Alloy EN82H cladding. The specimens featured semi-elliptical surface cracks penetrating approximately 6.3 mm of cladding into the underlying steel. The initial crack sizes were relatively large with surface lengths of 30.3--38.3 mm, and depths of 13.1--16.8 mm. The experiments were conducted in a quasi-stagnant low-oxygen (O 2 < 10 ppb) aqueous environment at 243 degrees C, under loading conditions (ΔK, R, and cyclic frequency) conductive to environmentally-assisted cracking (EAC) in higher-sulfur steels under quasi-stagnant conditions. Earlier experiments on unclad compact tension specimens of this heat of steel did not exhibit EAC, and the present experiments on semi-elliptical surface cracks penetrating cladding also did not exhibit EAC

A model for TRIP steel constitutive behaviour

NARCIS (Netherlands)

Perdahcioglu, Emin Semih; Geijselaers, Hubertus J.M.; Menari, G