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Welding is the process of joining materials in the manufacturing industry. To maintain the quality of welding results in accordance with established standards, it is necessary to inspect or inspect the product. To find out whether or not there are defects in the product before the next process is carried out, or before the product is marketed, an inspection is usually carried out using a nondestructive testing (NDT) method, namely testing materials without damaging the material being tested. Several types of non-destructive testing, namely, visual checking, penetrant test, radiographic test and magnetic particle test. This article discusses about the welding analysis of stringer tertiary screen at PT PAL Indonesia. To check whether there are defects in the welded joints in the stringer tertiary screen, a visual check and magnetic particle test have been carried out. Based on interpretation using ASME section IX, the test results show that there are several defects such as spatter on the base metal and wormholes which are unacceptable. The finding of this defect has been followed up with re-welding repairs as recommended. For spatter defects, repairs are carried out with the help of an air chipping hammer which functions to clean the spatter from the base metal, then for wormhole defects repairs are carried out by dismantling the weld and re-welding. The results of repeated visual checks and magnetic particle tests after repair showed that the defects had been successfully eliminated. Thus, the welding results on the stringer tertiary screen are acceptable. [ABSTRACT FROM AUTHOR]

Liquefied petroleum gas (propane or butane) is a colorless liquid which readily evaporates into a gas. It has no smell, although it will normally have an odor added to help detect leaks. Liquefied petroleum gas is stored and handled as a liquid when under pressure inside an LPG cylinder. Liquefied petroleum gas cylinders are subjected to various tests to ensure their compliance requirements as per standard. This research studies the durability of welding and performance of base metal of L. P. G. home cylindrical in Kurdistan region. The experiments were carried out on three types of LPG cylinder using in Kurdistan regions A, B, and C and an unformed plate. To carried out the samples and tests during the research we depending on the standard tests for LPG cylinders. Three samples are extracted from each of LPG cylinders and unformed plate for each of tensile test, Bending test and Hardness test according to ISO 6892-2016 and ASME standards from each type of LPG cylinders and from unformed plate to examine the mechanical properties. In addition, chemical compositions also were carried out. These values are compared with standard.

In this article, a structural integrity assessment of ITER Torus Cryo-Pump Housing (TCPH) is presented. TCPH is a penetration structure located on the cryostat cylinder whose main function is to accommodate and support the Torus Cryo-Pump (TCP), connect it to the vacuum vessel (VV), and provide tritium confinement and primary vacuum boundary. The design of the TCPH structure was finalized during the final design review (FDR). After the FDR, based on the manufacturing feasibility study, changes in the design were proposed to facilitate the nondestructive examination of weld joints. To qualify the proposed changes, structural integrity assessment was performed as per Section VIII Div. 2 Part 5 of ASME code by finite-element analysis using ANSYS software. The structural and thermal assessment was done as per TCPH load specification for protection against plastic collapse, local failure, ratcheting, buckling, and fatigue to perform the structural integrity of the TCPH. The results obtained from the integrity assessment qualified the design criteria. Margins available over allowable stress values for plastic collapse, local failure, and ratcheting are 20%, 19%, and 30%, respectively. A buckling factor of 79 was achieved with a minimum allowable value of 13.42. For fatigue, a usage fraction of 0.516 was obtained against allowable maximum value of 1. Thus, the design with proposed changes was qualified and incorporated. [ABSTRACT FROM AUTHOR]

• The design of the EC window unit, already optimized by FEM analysis, was advanced by ASME III-NC and the manufacturing aspects. • The design of the EC window unit was adapted to the ITER project decision to reduce the inner diameter of the waveguides from 63.5 to 50 mm. • The design of the EC window unit is sufficiently mature to start the prototyping and testing activity in view of the ITER final design review. The torus window unit is a very particular component of the ITER EC H&CD upper launcher aiming to provide the primary vacuum and confinement boundary between the vacuum vessel and the transmission lines (TLs). The high power 170 GHz millimeter-wave beams generated by the gyrotrons travel along the TLs and pass through the window units, before being quasi-optically guided into the plasma via the upper launchers. The design of the window unit shall thus meet stringent requirements to guarantee the safety function, the millimeter-wave beam transmission and the structural integrity during normal operation and off-normal events. The unit consists of an ultra-low loss CVD diamond disk brazed to two copper cuffs; this structure is then integrated into a metallic housing by welding. The compliance with the requirements shall be assured by applying the ASME Section III – Subsection NC code and a dedicated experimental qualification program. This paper reports the way in which the design of the unit, already optimized by FEM analyses against the ITER loading conditions, was further improved by the application of the ASME III-NC code, leading to a more feasible and simpler manufacturing and assembling sequence. In addition, the impact of the ITER project decision to change the inner diameter of the waveguide from 63.5 to 50 mm, to improve the beams' mode purity, was assessed and it is also discussed. Different materials for the metallic housing and in particular for the millimeter-wave inserts of the unit were compared using appropriate engineering criteria to mitigate the significant increase of the millimeter-wave thermal loads on the waveguides when the diameter is decreased. [ABSTRACT FROM AUTHOR]

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Conventional analysis methods for piping systems have incorporated many conservative assumptions. Some of these assumptions can be abandoned by employing advanced analyses, thus allowing for higher loads, which can lead to further uprating of the system without physically intervening with it. This paper shows the procedure of uprating the design seismic load of an existing pipeline through advanced analyses. First, it was discovered that the seal between the pipe and the wall in fact represents a support which is even stiffer than an engineered, purposely built support. Secondly, analyses demonstrate that a pipeline built of thin wall pipes can sustain significant lateral deformation (ovalization and indentation), imposed by seismically induced relative displacements between the buried pipe and building wall penetration, without breaching the pipe wall. This finding is supported by the fact that the pipe passed the flattening test. In the pipeline qualification procedure, the stress state in the dented pipe wall is compared with the stress state during the flattening test. All relevant stress indicators (stress intensities) at the uprated loading state were smaller than allowed by the applicable code or obtained from the flattening test; thus, the pipeline qualified for uprated seismic conditions. [ABSTRACT FROM AUTHOR]

Highlights • An experimental set up is being developed for studying thermo-fluid MHD phenomenon. • The maximum magnetic field achievable is 1.4 T in the polar area of 400 × 1000 mm2 and a pole gap of 370 mm. • Detailed engineering analysis has been performed for the design optimisation of components & loop. • Pipe flexibility analysis has been performed to accommodate the thermal stresses in the loop piping. • Selection of MHD test mock ups has been done for first phase of MHD experiments. Abstract In the frame of the design and development of Liquid breeder blankets, a number of R & D activities are in progress in the area of liquid metal technology development. In presence of strong plasma confining toroidal magnetic field, motion of electrically conducting liquid metal leads to Magneto Hydro Dynamic (MHD) phenomena, as a consequence of which liquid metal flow profile changes inside the flow channels of liquid breeder blankets and additional pressure drop occurs due to the flow opposing Lorentz force (J × B). For the design and development of liquid breeder blankets, 3D MHD flow needs to be studied for various flow configurations as present in the liquid breeder blankets. A lead lithium (Pb-Li) MHD loop is being developed at IPR to perform MHD experiments for Pb-Li flow in various flow geometry such as U-bend, transition zones, circular pipes, sudden expansion and contraction, etc. The test mock ups will be placed in a uniform magnetic field up to 1.4 T, produced by a C-shaped Iron core electromagnet with a pole gap of 370 mm. Both Isothermal and thermo-fluid MHD experiments are being planned for MHD database generation and code validation. [ABSTRACT FROM AUTHOR]

This study evaluates the structural feasibility of a prismatic pressure vessel using strength assessments. A prismatic pressure vessel, which differs from a cylindrical or spherical pressure vessel, is proposed. A prismatic pressure vessel can be used to ship liquefied gas. A prototype of the prismatic pressure vessel was designed, manufactured and tested in accordance with the ASME Boiler and Pressure Vessel Code. Its design uses the “design-by-analysis” method, including protection against plastic collapse. The prototype of the prismatic pressure vessel uses typical construction materials considering their linear elastic and nonlinear plastic behaviors. The vulnerable components of the structure were obtained through numerical analysis using the finite element method. A pressure test with strain gauges was conducted, and the results demonstrate the feasibility of the prismatic pressure vessel as a suitable vessel for high-pressure fluids with high volume efficiencies. The prismatic pressure vessel has potential for general applicability in the shipping of liquefied gas. [ABSTRACT FROM AUTHOR]

Indian negative-ion source development program has gained momentum with planned integration of Indian Test Facility (INTF) for International Thermonuclear Experimental Reactor (ITER)—Diagnostic Neutral Beam (DNB) characterization at the Institute for Plasma Research (IPR). Eight RF driver-based negative-ion source, being developed for DNB will be tested and operated in INTF. The Two driver-based Indigenously built Negative ion source (TWIN) source provides a bridge between the operational single driver-based negative-ion source test facility, ROBIN in IPR, and an ITER-type multidriver-based ion source. The source is designed to be operated in continuous mode with 180 kW, 1 MHz, 5-s on/600-s off duty cycle and also in 5-Hz modulation mode with 3-s on/20-s off duty cycle for three such cycles. The complete design of TWIN source and its test facility, from conceptual to detailed engineering, has been carried out in IPR. The manufacturing design has been optimized to match the capability of Indian manufacturers, without compromising on the specifications. Some examples of optimization are: 1) an improvised design of the Faraday shields where electrodeposition has been replaced by vacuum brazing; 2) a simplified design of the side walls of the plasma source, where jointing process is simplified, without the application of Electron Beam Welding; and 3) introduction of a fiber reinforced polymer-based integrated electrical and vacuum isolation scheme that replaces the application of a large ceramic. Finite-element analysis (FEA) based on heat load and structural load calculation ensure the functionality and structural integrity of each component of the source. Due to nonnuclear environment in TWIN source experimental area, vacuum brazing is an acceptable manufacturing process. The contract for manufacturing of the ion source has been awarded to an Indian manufacturing company for the first indigenous production of a large-size fusion grade ion source. TWIN source is designed in such a way that it can be operated both in air mode (RF driver coil antennas are exposed to air) as well as vacuum mode. (Whole source is immersed inside vacuum.) The TWIN source shall be manufactured as per ASME guidelines for pressure vessel. Experiments on the TWIN source are foreseen in the last quarter of 2015, as all the auxiliary systems such as 180-kW, RF generator system, vacuum vessel with pumping station, cooling water system, data acquisition and control system, and other power supply systems are already installed in the lab premises. This paper discusses the FEA-based engineering design, simplified manufacturing design, manufacturing experience with highlighting quality control, and the system integration activities undertaken for the TWIN source test facility. [ABSTRACT FROM PUBLISHER]

This research proposed a prismatic pressure vessel for gas-fuel storage on a gas-fuelled ship. The prismatic pressure vessel consisted of flat-plated shells, stiffeners, and beam structures. According to the design principle of pressure vessels, the beam structures were designed to receive tensile stresses generated from the internal pressure. International regulations and a finite element analysis were considered for the design, strength calculations, fatigue assessments, plastic collapse, and thermal effects. A case study in which the prismatic pressure vessel was applied as a gas-fuel tank to provide ship propulsion on a crude-oil tanker was performed. Nine per cent nickel steel was used to be applicable for cryogenic service. Several design loadings were considered to evaluate the design feasibility of the pressure vessel. The computational analysis results indicated that the prismatic pressure vessel satisfied the design regulations and should be applicable for use as a gas-fuel storage tank for ships. [ABSTRACT FROM AUTHOR]

Gasketed bolted flange joints are used in process industry for connecting pressure vessels and pipes. Design procedures available in the literature mostly discuss structural strength, while sealing failure is still a big concern in industries. Similarly, limited work is found in the literature regarding performance of gasketed bolted joints under combined loading. A detailed 3D nonlinear finite element analysis is performed to study the strength and sealing of a gasketed bolted flanged pipe joint under different bolt-up strategy (Industrial and ASME) and under combined internal pressure and axial loading. [ABSTRACT FROM AUTHOR]

Recent advances in the digitization of manufacturing have prompted ASME and International Organization for Standardization (ISO) standards committees to reexamine the definition of datums. Any new definition of datums considered by the standards committees should cover all datum feature types used in design and support both traditional metrological methods and new digital measurement techniques. This is a challenging task that requires some careful compromise. This paper describes and analyzes various alternatives considered by the standards committees. Among them is a new mathematical definition of datums based on constrained least-squares fitting. It seems to provide the best compromise and has the potential to support advanced manufacturing that is increasingly dependent on digital technologies., Competing Interests: Conflict of Interest There are no conflicts of interest.

The ITER blanket Shield Block is a bulk structure to absorb radiation and to provide thermal shielding to vacuum vessel and external vessel components, therefore the most significant load for Shield Block is the thermal load. In the previous study, the thermo-mechanical analysis has been performed under the inductive operation as representative loading condition. And the fatigue evaluations were conducted to assure structural integrity for Shield Block according to Structural Design Criteria for In-vessel Components (SDC-IC) which provided by ITER Organization (IO) based on the code of RCC-MR. Generally, ASME code (especially, B&PV Sec. III) is widely applied for design of nuclear components, and is usually well known as more conservative than other specific codes. For the view point of the fatigue assessment, ASME code is very conservative compared with SDC-IC in terms of the reflected K e factor, design fatigue curve and other factors. Therefore, an accurate fatigue assessment comparison is needed to measure of conservatism. The purpose of this study is to provide the fatigue usage comparison resulting from the specified operating conditions shall be evaluated for Shield Block based on both SDC-IC and ASME code, and to discuss the conservatism of the results. [ABSTRACT FROM AUTHOR]

In a national project, with the aim to develop a robust method for structural verification of pressure equipment subjected to ratcheting, a two-rod test approach is developed. Two testing machines, with one specimen in each, are controlled in such way that a constant primary load and a cyclic secondary load are applied on the specimens. The ferritic steel P265 and the austenitic steel 316L are tested for a number of load combinations. Test results show that ratcheting is produced in all tests. As expected, the amount of ratcheting increases with the load level. At the start of a two-rod test, structural ratcheting dominates over material ratcheting. Depending on the load level and combination of primary load and cyclic secondary load, material ratcheting might eventually become more important. Based on results from tensile testing and fully-reversed strain controlled cycling, five different constitutive models are calibrated. The possibility to simulate the response of the conducted experiments with the different models is investigated. The most advanced model investigated, i.e. the nonlinear kinematic Chaboche model, does not necessarily give the best predictions. Up to a strain level of 5%, i.e. the criterion in ASME NB-3228.4, the bi-linear model best predicts the experiments. Recommendations for how ratcheting in structures subjected to cyclic plastic deformation can be predicted by numerical simulation are given. [ABSTRACT FROM AUTHOR]

• The comparison of thermal striping assessment results between RCC-MRx and ASME, within the common domain of the two codes. • The treatment of the main components liquid metal-cooled research reactor core that is undergoing severe conditions. • The main result illustrates that RCC-MRx gives more realistic values than ASME. The thermal striping phenomenon is a random temperature fluctuation that may cause thermal fatigue damage to components until the significant reduction of their lifetime or their fast break. It leads to creating some hazardous situations, which can cause the failure of mechanical systems. In the nuclear industry, components with a level of safety should be designed to prevent fatigue damage. In case of the occurrence of fatigue crack initiation on the component during service, it is required to analyse the causes and the consequences, most of the time, leading in the replacement of the component and modifying the causes (bad surface finish, residual stresses, etc.) to avoid future appearance damage. Indeed, in the case of liquid metal-cooled nuclear research reactors, the reactor core' component integrity can be threatened and that should push engineers to be more meticulous in their job. Engineering industry standards and computation software provide engineers with efficient rules to study this phenomenon and find suitable solutions. Among them, RCC and ASME, which are widely used in the world. Globally, codes are similar but some differences exist in their approaches that lead to bringing additional technical difficulties for engineers. In this paper, the methodologies of surface stress calculation in pipes are compared between RCC-MRx and ASME III subsection NB. The goal is to estimate the gap and identify the main causes of differences in the risk assessment of thermal striping in research reactors cooled by liquid metal. Based on the lifetime computations from two code procedures, comparison between the main parameters is done. Results show an acceptable similarity between linear temperatures and tangible differences for second temperature and stresses. These results prove the existence of a gap between codes. It reveals that the risk assessment of thermal striping is approached more conservatively by the RCC-MRx than by ASME, in this studied case. [ABSTRACT FROM AUTHOR]

In a national project, with the aim to develop a robust method for structural verification of pressure equipment subjected to ratcheting, a two-rod test approach is developed. Two testing machines, with one specimen in each, are controlled in such way that a constant primary load and a cyclic secondary load are applied on the specimens. The ferritic steel P265 and the austenitic steel 316L are tested for a number of load combinations. Test results show that ratcheting is produced in all tests. As expected, the amount of ratcheting increases with the load level. At the start of a two-rod test, structural ratcheting dominates over material ratcheting. Depending on the load level and combination of primary load and cyclic secondary load, material ratcheting might eventually become more important. Based on results from tensile testing and fully-reversed strain controlled cycling, five different constitutive models are calibrated. The possibility to simulate the response of the conducted experiments with the different models is investigated. The most advanced model investigated, i.e. the nonlinear kinematic Chaboche model, does not necessarily give the best predictions. Up to a strain level of 5%, i.e. the criterion in ASME NB-3228.4, the bi-linear model best predicts the experiments. Recommendations for how ratcheting in structures subjected to cyclic plastic deformation can be predicted by numerical simulation are given. [ABSTRACT FROM AUTHOR]

The ITER electron cyclotron (EC) upper launcher has passed the CDR (conceptual design review) in 2005 and the PDR (preliminary design review) in 2009 and is in its final design phase now. The final design will be elaborated by the European consortium ECHUL-CA with contributions from several research institutes in Germany, Italy, the Netherlands and Switzerland. Within this consortium KIT is responsible for the design of the structural components (the upper port plug, UPP) and also the design integration of the launcher. As the selection of applicable codes and standards was under discussion for the past decade, the conceptual and the preliminary design of the launcher structure were not elaborated in straight accordance with a particular code but with a variety of well-acknowledged engineering practices. For the final design it is compulsory to validate the design with respect to a typical engineering code in order to be compliant with the ITER quality and nuclear requirements and to get acceptance from the French regulator. This paper presents typical design validation of the closure plate, which is the vacuum and Tritium barrier and thus a safety relevant component of the upper port plug (UPP), performed with the ASME boiler and pressure vessel code. Rationales for choosing this code are given as well as a comparison between different design methods, like the “design by rule” and the “design by analysis” approach. Also the selections of proper load specifications and the identification of potential failure modes are covered. In addition to that stress categorizations, analyses results, and prove of the soundness of the design are presented. [ABSTRACT FROM AUTHOR]

This article describes the process of design and construction of a storage tank hot water (DHW) for domestic consumption is presented. In addition, mathematical analysis is described, the selection of materials for both insulation and the body of the tank, hydrostatic simulation behavior, the construction process based on ASME Section VIII and testing operation. This work is part of a research project aimed at designing and construction of solar heaters from reusable materials by the hotbed of research SEA belonging to the group of alternative energy research GIEAUD District University of Francisco José de Caldas. The solar heater and the tank are mounted on the roof of the gym located in the Faculty of Technology. Tests were performed to evaluate the efficiency in maintenance of the temperature and currently continues with additional tests to better observe the performance of the tank. [ABSTRACT FROM AUTHOR]

Nowadays in the world of industrial plants it is becoming always much more important to have an available adequate technology that allows to perform temporary repairs of metallic pipes, tanks and vessels in order to maintain the structural stability and to guarantee the safe operation until the next planned pressure equipment verification. On the basis of ISO/TS 24817 technical specification, ASME PCC-2 and ASME B31G standard it was developed and set up a temporary repairing technique with composite materials consisting of two-components epoxy thermoset resins, primers, epoxy putty and mastics and carbon fibers woven roving cloths as mechanical layers of laminations. These temporary repairs performed in the continuous service plants were realized according to Art. 36 of Dig. n. 83 dated 22/06/2012, UNI/TS 11325-5:2012 and Circolare ISPESL 2592/09 dated 8/7/09. [ABSTRACT FROM AUTHOR]

In the construction of welded structures the research, evaluation and acceptability of imperfections in welded joints are fondamental aspects. In the field of metallic constructions, imperfections can be divided into two groups: linear and non-linear imperfections. Imperfection becomes a defect if it does not fall within the acceptance criteria defined by code or designer and from there derives several corrective actions, such as heat treatment, painting, repairing... The different international codes examined show some common points on implementation of non-destructive testing, but very different are their approaches to the acceptance criteria. A designer choice of a particular acceptance criteria can be summarized in a few key points: stress evaluation of the welded joints, in service conditions, mechanical properties of materials, inspection procedures. The purpose of this paper is a comparison of international standards (European, American and Russian Codes) for the acceptance of imperfections in welded joints. [ABSTRACT FROM AUTHOR]

The development of electrical energy production systems, to improving efficiency and reducing noxious emissions, requires higher steam temperatures. To support these typical conditions of "critical" and "supercritical" plants, creep resistant steels are required, in order to perform increasing service conditions, with same pressure parts, within industrially advantageous design values. The use of martensitic steel, grade 92, represents a valid solution today, but requires the adoption of a technological way that does not damage original material performance, in fact it is very complex to assess, in process production and in service operations, possible consequences through control techniques used to date. Complying with essential codes or rules requirements is not a sufficient condition to ensure the suitability of these steels, the key of success is represented by microstructure analysis and evaluation. [ABSTRACT FROM AUTHOR]

The objective of this work is to find out the stress intensity and load confrontation of the axially cracked ASME pressure vessels so that the condition of the vessel will be branded how much more the life of the vessel wall would come if the crack is generated during operating conditions. The background of this work is based on the failures often occurring in the oil, gas and chemical plant industries. Process equipments are having its own standard design procedures and operating life's according to its material properties. Some of the equipments need frequent refurbishment as well as proper maintenance during operations due to the various working conditions. The code practices that process equipments need to be designed for time span of 20 to 25 years. However failures occurring during operations are unpredictable but it is diagnosable. It may be due to various reasons such as malfunctioning of components and wrong operations. In this paper the work is such that if the crack is generated axially inside due to load or corrosion, how much more operation the vessel would sustain. If the cracks grow continuously due to frequent loads how long the un-cracked thicknesses would withstand the internal pressure loads. ASME based designed pressure vessel has been considered for this study. The typical pressure vessel crack has been modeled internally in axial directions. The operating load has been applied and the behavior of cracks and its load confrontations were simulated using finite element technology and the results were presented. [ABSTRACT FROM AUTHOR]

With the development of E-commerce, more scholars have paid attention to research on Mobile E-commerce and mostly focus on the optimization and evaluation of existing process. This paper researches the evaluation of Mobile E-commerce process with a method called ASME. Based on combing and analyzing current mobile business process and utilizing the grid management theory, mobile business process based on grid are constructed. Firstly, the existing process, namely Non-grid Mobile E-commerce, and the Grid Mobile E-commerce process are ordered. Secondly the evaluation system with ASME is formed. Thirdly, the benefits of the Grid Mobile E-commerce process are presented. This paper provides a new way to evaluate Mobile E-commerce. [ABSTRACT FROM AUTHOR]

Abstract: Inspection of the weld between the feedwater nozzle and the safe end at one Taiwan BWR showed axial indications in the Alloy 182 weld. The indication was sufficiently deep that continued operation could not be justified considering the crack growth for one cycle. A weld overlay was decided to implement for restoring the structural margin. This study reviews the cracking cases of feedwater nozzle welds in other nuclear plants, and reports the lesson learned in the engineering project of this weld overlay repair. The overlay design, the FCG calculation and the stress analysis by FEM are presented to confirm that the Code Case structural margins are met. The evaluations of the effect of weld shrinkage on the attached feedwater piping are also included. A number of challenges encountered in the engineering and analysis period are proposed for future study. [Copyright &y& Elsevier]

Abstract: Nitrogen-alloyed type 316L stainless steel is the major structural material for the high temperature structural components of prototype fast breeder reactor. For the welding electrode, carbon in the normal range of 0.045–0.055wt% and nitrogen in the range of 0.06–0.1wt% are used to provide weld joints with adequate long term creep strength. Characterization of the creep properties of the base metal, weld metal and weld joint has been carried out at 873 and 923K at stress levels of 100–325MPa with rupture lives in the range of 100–33,000h. Weld strength reduction factors (WSRFs) based on the weld metal, and weld joint have been evaluated, and compared with the codes. WSRFs for the weld joint were higher than the RCC-MR values. Base metal showed the highest rupture life at all the test conditions whereas the weld metal generally showed the lowest rupture life. All the weld joint specimens failed in the weld metal. [Copyright &y& Elsevier]

This paper presents the results of a parametric study of the behaviour of metal-to-metal contact flanges that have different surface profiles. Using a finite element analysis approach, the important stress values in the flange and bolts and flange rotation/displacement have been obtained for variations in flange thickness, bolt pre-stress and taper angle (different surface profiles) whilst maintaining other leading flange dimensions (hub length and hub thickness) constant, when the vessel/flange component is subjected to internal pressure. In addition, results are compared for the flange geometry with no taper angle on the flange surface with the predictions obtained from the appropriate sections of the ASME, PD5500 and new European unfired pressure vessel standard EN 13445 Part 3. Based on the results of this study, the best flange dimensions are recommended for ‘no leak’ conditions from the joint. [Copyright &y& Elsevier]

Practical implementation of a much more realistic approach for treating external moments for various major flange assessment methods is proposed. First, the question of how to deal with torsion in flange rings weakened by bolt holes is addressed. This aspect was not covered by the original paper of Mr Koves on which our work is based. That our practical implementations result in quite accurate results is shown by an FEM-analysis of a loose flange ring.Correctly dealing with external moments, usually the major part of external loads on flanges, is important because as soon as design pressures are known, flange ratings are selected and initial designs for ‘custom’ flanges are made. Only in the later stages of a project do all loads on flanges become available and then these external flange loads have to be approved. Usually, the margins between internal pressures and maximum allowable pressures are not large and hence one can ill-afford the wasteful ways that flange assessment methods presently treat external loads. [Copyright &y& Elsevier]

The American Society of Mechanical Engineers (ASME) [K.sub.Ic] curve is a function of test temperature (T) normalized to a reference nil-ductility temperature, [RT.sub.NDT], namely, T - [RT.sub.NDT]. It was constructed as the lower boundary to the available [K.sub.Ic] database. Being a lower bound to the unique but limited database, the ASME [K.sub.Ic] curve concept does not discuss probability matters. However, a continuing evolution of fracture mechanics advances has led to employment of the Weibull distribution function to model the scatter of fracture toughness values in the transition range. The Weibull statistic/master curve approach was applied to analyze the current ASME [K.sub.Ic] database. It is shown that the Weibull distribution function models the scatter in [K.sub.Ic] data from different materials very well while the temperature dependence is described by the master curve. probabilistic-based tolerance-bound curves are suggested to describe lower-bound [K.sub.Ic] values.

In this study, the design and strength of prismatic pressure vessels with new geometries for use as fuel tanks in LNG-fueled ships were assessed. The plate-stiffened prismatic pressure vessel had a rectangular cross-section unlike that of the conventional cylindrical pressure vessel; furthermore, its structure was capable of withstanding load by using a plate inside. ASME, and IGC/IGF codes were analyzed and the design procedure for a novel shaped pressure vessel was confirmed. A case study of an LNG fuel tank on a LNG fueled crude oil tanker was conducted. The design feasibility of the plate-stiffened prismatic pressure vessel was evaluated by conducting strength analysis at the design pressure and test vapor pressure. Furthermore, ultimate strength, dynamic acceleration, buckling, and thermal/fatigue analyses were conducted. As a result of the analyses, it was confirmed that a plate-stiffened prismatic pressure vessel could be used as a fuel tank in LNG fueled ships, according to the design regulations. • A prismatic pressure vessel with plate-stiffened for LNG fuel on ships is proposed. • This study evaluates the structural feasibility of a prismatic pressure vessel using strength assessments. • The results indicate the suitability of the vessel for liquefied gas fuel on ships. [ABSTRACT FROM AUTHOR]

The American Society of Mechanical Engineers has named the Split-Hopkinson Pressure Bar Apparatus at Southwest Research Institute a Historic Mechanical Engineering Landmark. The instrument is a mechanical system designed to […]

ASME International presented Michael Gold, president, Gold Metallurgical LLC, with its J. Hall Taylor Medal in July. He was recognized for outstanding contributions and leadership in the development and international […]