Download or read book Assessment of Weld Residual Stress Effects on Fatigue Crack Propagation in Ferritic Pressure Vessel Steels written by Carlos Efren Jimenez Acosta and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Quantitative Assessment of the Residual Stress Effects on Fatigue Crack Propagation in Structural Steel Weldments in Air Seawater written by Leonardo Bertini and published by . This book was released on 1989 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fatigue Life Assessment of Steel Pressure Vessels with Varying Stress Concentration Residual Stress and Initial Cracks written by and published by . This book was released on 1996 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: A single-parameter representation of local stress range, initial crack size, and material yield strength is proposed for describing the intensity of the fatigue loading of a structural component. A logarithmic plot of single-parameter fatigue life results provides a single straight-line description of fatigue life behavior over a broad range of material, configuration, and loading conditions. Expressions for calculating the local stress range at the failure site are outlined, including effects of vessel and stress concentrator configuration, applied and overstrain residual stresses, and pressure applied to hole and crack surfaces. The single-parameter approach was used in a comparison of fatigue life results from 41 full-size hydraulic pressure cycle tests of cannon pressure vessels with 12 combinations of material strength, failure location, and applied and residual stresses. A log plot of mean results of the 12 data groups is well represented by a single straight line with a negative slope reasonably close to that predicted by fracture mechanics analysis. A significant outlier from the straight-line trend of the data is a useful indicator of cracking due to other than conventional mechanical fatigue. Two examples of an outlier from the trend of cannon pressure vessel data were confirmed by metallography to be caused by environmental cracking. A third outlier was related to preexisting initial cracks due to rapid machining. The effect of material yield strength on fatigue behavior can be simply and well represented using the single-parameter approach. The R2 correlation coefficient of a logarithmic straight-line fit to the 12 sets of cannon pressure vessel results increased from 0.81 to 0.86 upon inclusion of the effect of material strength.
Download or read book Computational Weld Mechanics Constraint and Weld Fracture written by F. Brust and published by . This book was released on 2002 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation These 26 technical papers from the August 2002 conference present novel analytical and experimental methods related to fracture mechanics, computational weld mechanics, and residual stresses for evaluation of the structural integrity and reliability of pressure vessels and piping. Bi-metallic welds, finite elements and constraint effects on fracture, and large scale weld modeling of structures are addressed. Topics include fracture assessment of a clad steel using the SINTAP procedure, lump pass welding simulation technology for shipbuilding applications, and the determination of constraint-modified J-R curves for carbon steel storage tanks. No subject index. Annotation c. Book News, Inc., Portland, OR (booknews.com).
Download or read book Residual Stress and Its Effects on Fatigue and Fracture written by Anastasius Youtsos and published by Springer Science & Business Media. This book was released on 2007-05-20 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The contents of this book have been grouped into three topic areas covering theoretical /numerical and experimental analyses of residual stress and its effects on fatigue and fracture. It details recent advances on its title topics by leading European experts and contains theoretical/numerical studies of high value backed by sound experimental data. It also provides experimental studies based on novel and verifiable testing methods.
Download or read book Fracture Fatigue and Weld Residual Stress written by and published by . This book was released on 1998 with total page 345 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Review of Fatigue Crack Growth of Pressure Vessel and Piping Steels in High temperature Pressurized Reactor grade Water written by W. H. Cullen and published by . This book was released on 1980 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth data sets, for pressure vessel and piping steels, in reactor-grade water environment have appeared in various reports and publications since about 1972. All of the results which have been published from 1972 through 1979 have been plotted and are presented in this report. Beginning with a discussion of the need for these data, and an explanation of the laboratory facilities which are required for this research, this report goes on to describe the overall trends which have evolved through consideration of the data sets and the conditions under which they were generated. A model for hydrogen assisted fatigue crack growth is described and applied to the pressurized water reactor type of environment. A complete listing of references is included in the report. (Author).
Download or read book The Combined Effects of Residual Stress and Warm Prestressing on Cleavage Fracture in Steels written by Karin Rosahl and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: When the structural integrity of the reactor pressure vessel (RPV) in a pressurised water re- actor (PWR) is analysed, certain types of postulated accidents have to be considered. The conditions during a loss-of-coolant accident (LOCA) resemble a warm prestressing (WPS) sce- nario. Warm prestressing refers to a prior overload sequence which in certain circumstances improves the fracture resistance of a ferritic steel structure. Furthermore, a RPV is a welded structure. The welding process gives rise to residual stresses (RS) that can have a significant influence on the integrity of the RPV. Tensile residual stresses are often regarded as unwanted and detrimental. Previous work has not studied the combined effects of WPS and RS on the fracture behaviour of ferritic steel components. The purpose of this dissertation is to explore the combined effects of WPS and RS by means of robust statistical techniques. To describe the effects of WPS, two models are investigated. A local model using the near crack tip stresses and strains (often called the Beremin model) is usually used to predict the fracture probability of as-received material and can be adapted to include the effects of WPS. However, this requires the use of a detailed finite element analysis. The Chell model, on the other hand, is a deterministic model developed to explain the beneficial effects ofWPS on fracture toughness. Using a Monte Carlo (MC) simulation approach, the Chell model is extended to enable failure probability distributions to be determined. The failure probabilities are compared with both experimental data from the literature and results of an experimental test programme on compact tension specimens. It is found that the MCS approach used in conjunction with the Chell model provides robust and accurate predictions of the failure probability following WPS. To extend the analysis to include residual stress, a novel preloading rig model for introducing a known tensile RS into laboratory fracture specimens is investigated. It is found that the Chell model is to be preferred over the Beremin model. The Chell model provides robust and accurate predictions of the fracture behaviour after WPS, yet its application is straight forward and less time expensive than the Beremin model. The combined effects of WPS and a tensile RS field on the failure probabilities can be analysed by combining the Chell model with the preloading rig model and applying a Monte Carlo simulation approach. Contrary to expectations, it is shown that a tensile RS field can have a significant beneficial effect on the failure distribution after WPS.
Download or read book Effect of Residual Stresses on Fatigue Crack Growth in Steel Weldments Under Constant and Variable Amplitude Loads written by G. Glinka and published by . This book was released on 1979 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research deals with the effect of welding residual stresses on fatigue crack growth in medium strength low alloy steel weldments. Three kinds of flat specimens have been used--unwelded specimens, specimens with butt perpendicular welds, and specimens with butt longitudinal welds. Residual stress distributions were others in both kinds of welded specimens. All specimens were tested under constant and variable amplitude load with stress ratios R > 0. Forman's equation and Wheeler's model of crack retardation were used for theoretical analysis of fatigue crack growth under constant and variable amplitude load, respectively. The theoretical results were more realistic when effective stress ratio Reff and effective stress intensity range ?Keff, which compensated for residual stresses, were used. It was found that the tensile residual stresses increased the fatigue crack growth rate and compressive stresses reduced it. The lower the applied load, the higher the residual stress effect. This paper presents both experimental results and an analytical method of fatigue crack growth prediction in steel weldments on the basis of results obtained from parent material properties.
Download or read book Brittle Fracture of Steel 1950 1961 written by and published by . This book was released on 1961 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The bibliography has been compiled from the unclassified literature for the period January 1950 through November 15, 1961. Reviews and bibliographies which have been listed furnish references to historical reviews and earlier studies on brittle fracture. An author and a subject index are included.
Download or read book Fatigue and Fracture Testing of Weldments written by Harry I. McHenry and published by ASTM International. This book was released on 1990 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fifteen papers from a symposium held in Sparks, Nev., April 1988. They cover: low and high cycle fatigue, fatigue crack growth, corrosion fatigue, fracture toughness testing, and wide-plate testing. Annotation copyright Book News, Inc. Portland, Or.
Download or read book Residual Stresses in Weld Deposited Clad Pressure Vessels and Nozzles written by and published by . This book was released on 1998 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: Results of through-thickness residual stress measurements are provided for a variety of samples of weld deposited 308/309L stainless steel and Alloy 600 cladding on low-alloy pressure vessel ferritic steels. Clad thicknesses between 5 and 9mm on samples that vary in thickness from 45 to 200mm were studied. The samples were taken from flat plates, from a spherical head of a pressure vessel, from a ring-segment of a nozzle bore, and from the transition radius between a nozzle and a pressure vessel shell. A layer removal method was used to measure the residual stresses. The effects of uncertainties in elastic constants (Youngs̀ modulus and Poissons̀ ratio) as well as experimental error are assessed. All measurements were done at room temperature. The results of this work indicate that curvature plays a significant role in cladding residual stress and that tensile residual stresses as high as the yield stress can be measured in the cladding material. Since the vessel from which the spherical and nozzle corner samples were taken was hydrotested, and the flat plate specimens were taken from specimens used in mechanical fatigue testing, these results suggest that rather high tensile residual stresses can be retained in the cladding material even after some mechanical loading associated with hydrotesting and that higher levels of hydrotest loading would be required to alter the cladding residual stresses.
Download or read book Selected Papers from PRES 2018 written by Jiří Jaromír Klemeš and published by MDPI. This book was released on 2020-06-17 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: The depletion of natural energy resources provides evidential adverse impacts on world economy functionality. The strong requirement of a sustainable energy supply has escalated intensive research and the discovery of cleaner energy sources, as well as efficient energy management practices. In the context of a circular economy, this research not only targets the optimisation of resources utilisation at different stages but also emphasises the eco-design of products to extend production life spans. Based on this concept, this book discusses the roles of process integration approaches, renewable energy sources utilisation and design modifications in addressing the process energy and exergy efficiency improvement. The primary focus is to enhance the economic and environmental performance through process analysis, modelling and optimisation. The articles mainly show the contribution of each aspect: (a) design and numerical study for innovative energy-efficient technologies, (b) process integration—heat and power, (c) process energy efficiency or emission analysis, and (d) optimisation of renewable energy resources’ supply chain. The articles are based on the latest contribution of this journal’s Special Issues in the 21st conference entitled “Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (PRES)”. This book is complemented with an editorial review to highlight the broader state-of-the-art development.
Download or read book Weld Cracking in Ferrous Alloys written by R Singh and published by Elsevier. This book was released on 2008-12-12 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: Weld cracks are unacceptable defects that can compromise the integrity of welded structures. Weld cracking can lead to structural failures which at best will require remedial action and at worst can lead to loss of life. Weld cracking in ferrous alloys reviews the latest developments in the design, evaluation, prevention and repair of weld cracks.Part one reviews the fundamentals as well as recent advances in the areas of welding technology, design and material selection for preventing weld cracking. Part two analyses weld crack behaviour, evaluation and repair of cracking/cracked welds. The book benefits from an extensive and robust chapter on the topic of NDE and quality control that was contributed by one of the most respected non-destructive evaluation and development groups in the world. Part three covers environment assisted weld cracking.With its distinguished editor and international team of contributors, Weld cracking in ferrous alloys is a valuable source of reference for all those concerned with improving the quality of welding and welded components. In the planning and development of this book, particular care has been taken to make the chapters suitable for people from other disciplines who need to understand weld cracking and failure. - Reviews the latest developments in the design, evaluation, prevention and repair of weld cracks - Assesses recent advances in welding technology, design and material selection - Analyses weld crack behaviour, evaluation and repair including environment assisted weld cracking
Download or read book Influence of Residual Stresses on Fatigue Crack Propagation in Electroslag Welds written by BM. Kapadia and published by . This book was released on 1978 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation of fatigue crack propagation behavior in air of as-deposited electroslag welds in two hot-rolled structural steels, prepared according to ASTM Specification for Structural Steel (A 36) and ASTM Specification for High-Strength Low-Alloy Structural Steel with 50 000 psi Minimum Yield Point to 4 in. Thick (Grade A) (A 588), has shown that the crack-growth rates (da/dN) in the welds were similar to or up to five times slower than the rate in the base steels. The retardation in crack-growth rate was observed to be substantially greater for crack propagation in the coarse-grained heat-affected-zone (HAZ) and bond-line regions than in the weld metal, but this was not consistently observed. Moreover, marked variations in the microstructure of the weld metal and HAZ did not significantly influence crack propagation. These crack-growth data for the weldments, described in an earlier paper, have been analyzed in the present paper in terms of residual stresses causing the observed retardation in crack-growth rate. In the present work, quantitative comparisons of the crack-growth behavior of the welds were based on a cyclic-life parameter (N1), which was defined as the number of cycles required for precracking the IT wedge-opening-loading (WOL) specimens to a total crack length of 2.54 cm (1 in.). This parameter gave results that were consistent with those based on incremental crack-growth (da/dN) data in the earlier paper. The observed retardation in crack-growth rate in the welds is attributed to compressive residual stresses introduced by welding. This effect was analyzed in the present paper in terms of a stress-intensity-range suppression concept, whereby the applied stress-intensity-factor range is decreased to some lower effective value. The results showed that the beneficial effect of compressive residual stresses on crack propagation appears to be of a variable nature and would diminish following a stress-relief heat treatment.
Download or read book Assessment Methodologies for Preventing Failure Deterministic and probabilistic aspects and weld residual stress written by Raj Mohan and published by . This book was released on 2000 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
