Download or read book Lifetime Estimation of Welded Joints written by Tadeusz Lagoda and published by Springer Science & Business Media. This book was released on 2008-01-10 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the paper the author attempts to assess the fatigue life of chosen welded joints. It focuses especially on chosen problems that accompany deter- nation of the fatigue life of welded joints, taking into consideration the strain energy density parameter. Chapter 2 describes the welded joint as a stress concentrator. The state of stress and strain in the notch are described and theoretical and fatigue coefficients are indicated. The fatigue coef- cient of the notch effect is estimated on the basis of fictitious radius in the notch root. Chapter 3 presents a model of fatigue life assessment under uniaxial stress state with statistical handling of data presented. The new energy model of fatigue life assessment, which rests upon the analysis of stress and strain in the critical plane, is described in detail in chapter 4. The principle of such a description is presented in the uniaxial as well as in - axial state of loading. Chapter 5 contains the analysis of tests of four ma- rials subjected to different loadings: cyclic, variable-amplitude with Ga- sian distribution, and variable amplitude with Gaussian distribution and overloading for symmetric and pulsating loading. The analysis is based on the determined fatigue characteristics for all the considered materials. Chapter 6 shows the application of the model in the fatigue life assessment in the complex state of loading (bending with torsion of flange-tube and tube-tube joints) based on fatigue research of steel and aluminum welded joints carried out in well-known German centres.

Download or read book Fatigue Life Analyses of Welded Structures written by Tom Lassen and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Avoiding or controlling fatigue damage is a major issue in the design and inspection of welded structures subjected to dynamic loading. Life predictions are usually used for safe life analysis, i.e. for verifying that it is very unlikely that fatigue damage will occur during the target service life of a structure. Damage tolerance analysis is used for predicting the behavior of a fatigue crack and for planning of in-service scheduled inspections. It should be a high probability that any cracks appearing are detected and repaired before they become critical. In both safe life analysis and the damage tolerance analysis there may be large uncertainties involved that have to be treated in a logical and consistent manner by stochastic modeling. This book focuses on fatigue life predictions and damage tolerance analysis of welded joints and is divided into three parts. The first part outlines the common practice used for safe life and damage tolerance analysis with reference to rules and regulations. The second part emphasises stochastic modeling and decision-making under uncertainty, while the final part is devoted to recent advances within fatigue research on welded joints. Industrial examples that are included are mainly dealing with offshore steel structures. Spreadsheets which accompany the book give the reader the possibility for hands-on experience of fatigue life predictions, crack growth analysis and inspection planning. As such, these different areas will be of use to engineers and researchers.

Download or read book Estimation of Fatigue Life of Welded Joint Using Vibration fatigue Computational Model written by Eniyavan Subramanian and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heavy vehicle structures are made from welded carbon steel frames. During operation these frames are subjected to random dynamic loads, which induce fatigue at the welded joints. A Finite Element based process for calculating fatigue life of welded joint under single excitation random loading is proposed in this study. The proposed method com-bines Equivalent Equilibrium Structural Stress (E2S2) method for weld fatigue and PSD based vibration fatigue technique for handling random loads. Fatigue life of a welded T-joint is analysed using the proposed method in frequency domain and validated against a transient dynamic analysis. The main advantage of the proposed method is the analysis run time is reduced almost 12 times compared to transient analysis. Effect of geometric changes on weld fatigue life is studied. It is found the tube thickness increase at lower thickness ranges significantly increases the fatigue life compared to higher thickness ranges.

Download or read book Residual Stress Analysis on Welded Joints by Means of Numerical Simulation and Experiments written by Paolo Ferro and published by BoD – Books on Demand. This book was released on 2018-05-16 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ability to quantify residual stresses induced by welding processes through experimentation or numerical simulation has become, today more than ever, of strategic importance in the context of their application to advanced design. This is an ongoing challenge that commenced many years ago. Recent design criteria endeavour to quantify the effect of residual stresses on fatigue strength of welded joints to allow a more efficient use of materials and a greater reliability of welded structures. The aim of the present book is contributing to these aspects of design through a collection of case-studies that illustrate both standard and advanced experimental and numerical methodologies used to assess the residual stress field in welded joints. The work is intended to be of assistance to designers, industrial engineers and academics who want to deepen their knowledge of this challenging topic.

Download or read book Fatigue Design of Marine Structures written by Inge Lotsberg and published by Cambridge University Press. This book was released on 2016-04-13 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue Design of Marine Structures provides students and professionals with a theoretical and practical background for fatigue design of marine structures including sailing ships, offshore structures for oil and gas production, and other welded structures subject to dynamic loading such as wind turbine structures. Industry expert Inge Lotsberg brings more than forty years of experience in design and standards-setting to this comprehensive guide to the basics of fatigue design of welded structures. Topics covered include laboratory testing, S-N data, different materials, different environments, stress concentrations, residual stresses, acceptance criteria, non-destructive testing, improvement methods, probability of failure, bolted connections, grouted connections, and fracture mechanics. Featuring twenty chapters, three hundred diagrams, forty-seven example calculations, and resources for further study, Fatigue Design of Marine Structures is intended as the complete reference work for study and practice.

Download or read book Fatigue Design ESIS 16 written by J. Solin and published by Wiley-Blackwell. This book was released on 1993-03-02 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: A compilation of research in fatigue design, prediction, and assessment Fatigue Design is a collection of research presented at the 1993 International Symposium on Fatigue Design. Detailing the latest findings and most current research, this book features papers on a variety of pertinent topics, including the quantification of service load for fatigue life predictions, identification of stress states and failure modes, assessment of residual life in damaged components, and more. Special attention is paid to the need for simple and reliable prediction tools to help better ensure adequate strength at the design stage.

Download or read book Fatigue Assessment of Welded Joints by Local Approaches written by Dieter Radaj and published by Woodhead Publishing. This book was released on 2006-10-30 with total page 661 pages. Available in PDF, EPUB and Kindle. Book excerpt: Local approaches to fatigue assessment are used to predict the structural durability of welded joints, to optimise their design and to evaluate unforeseen joint failures. This standard work provides a systematic survey of the principles and practical applications of the various methods. It covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. Seam-welded and spot-welded joints in structural steels and aluminium alloys are also considered.This completely reworked second edition takes into account the tremendous progress in understanding and applying local approaches which has been achieved in the last decade. It is a standard reference for designers, structural analysts and testing engineers who are responsible for the fatigue-resistant in-service behaviour of welded structures. - Completely reworked second edition of a standard work providing a systematic survey of the principles and practical applications of the various methods - Covers the hot spot structural stress approach to fatigue in general, the notch stress and notch strain approach to crack initiation and the fracture mechanics approach to crack propagation. - Written by a distinguished team of authors

Download or read book Structural Hot Spot Stress Approach to Fatigue Analysis of Welded Components written by Erkki Niemi and published by Springer. This book was released on 2017-08-28 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides background and guidance on the use of the structural hot-spot stress approach to fatigue analysis. The book also offers Design S-N curves for use with the structural hot-spot stress for a range of weld details, and presents parametric formulas for calculating stress increases due to misalignment and structural discontinuities. Highlighting the extension to structures fabricated from plates and non-tubular sections. The structural hot-spot stress approach focuses on cases of potential fatigue cracking from the weld toe and it has been in use for many years in tubular joints. Following an explanation of the structural hot-spot stress, its definition and its relevance to fatigue, the book describes methods for its determination. It considers stress determination from both finite element analysis and strain gauge measurements, and emphasizes the use of finite element stress analysis, providing guidance on the choice of element type and size for use with either solid or shell elements. Lastly, it illustrates the use of the recommendations in four case studies involving the fatigue assessment of welded structures using the structural hot-spot stress

Download or read book In service Non destructive Estimation of the Remaining Fatigue Life of Welded Joints written by Katie Marie Swanson and published by . This book was released on 2005 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book IIW Recommendations On Methods for Improving the Fatigue Strength of Welded Joints written by P J Haagensen and published by Woodhead Publishing. This book was released on 2013-01-25 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: The weld toe is a primary source of fatigue cracking because of the severity of the stress concentration it produces. Weld toe improvement can increase the fatigue strength of new structures significantly. It can also be used to repair or upgrade existing structures. However, in practice there have been wide variations in the actual improvements in fatigue strength achieved. Based on an extensive testing programme organised by the IIW, this report reviews the main methods for weld toe improvement to increase fatigue strength: burr grinding, TIG dressing and hammer and needle peening. The report provides specifications for the practical use of each method, including equipment, weld preparation and operation. It also offers guidance on inspection, quality control and training as well as assessments of fatigue strength and thickness effects possible with each technique. IIW recommendations on methods for improving the fatigue strength of welded joints will allow a more consistent use of these methods and more predictable increases in fatigue strength. Provides specifications for the practical use of each weld toe method, including equipment, weld preparation and operation Offers guidance on inspection, quality control and training, as well as assessments of fatigue strength and thickness effects possible with each technique This report will allow a more consistent use of these methods and more predictable increases in fatigue strength

Download or read book Fracture and Fatigue of Welded Joints and Structures written by K Macdonald and published by Elsevier. This book was released on 2011-04-19 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: The failure of any welded joint is at best inconvenient and at worst can lead to catastrophic accidents. Fracture and fatigue of welded joints and structures analyses the processes and causes of fracture and fatigue, focusing on how the failure of welded joints and structures can be predicted and minimised in the design process.Part one concentrates on analysing fracture of welded joints and structures, with chapters on constraint-based fracture mechanics for predicting joint failure, fracture assessment methods and the use of fracture mechanics in the fatigue analysis of welded joints. In part two, the emphasis shifts to fatigue, and chapters focus on a variety of aspects of fatigue analysis including assessment of local stresses in welded joints, fatigue design rules for welded structures, k-nodes for offshore structures and modelling residual stresses in predicting the service life of structures.With its distinguished editor and international team of contributors, Fracture and fatigue of welded joints and structures is an essential reference for mechanical, structural and welding engineers, as well as those in the academic sector with a research interest in the field. - Analyses the processes and causes of fracture and fatigue, focusing predicting and minimising the failure of welded joints in the design process - Assesses the fracture of welded joints and structure featuring constraint-based fracture mechanics for predicting joint failure - Explores specific considerations in fatigue analysis including the assessment of local stresses in welded joints and fatigue design rules for welded structures

Download or read book Fatigue Life Assessment of Welded Joints Based on the Decomposition of the Structural Hot Spot Stress written by Shahid M. Malik and published by . This book was released on 2006 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book IIW Guidelines on Weld Quality in Relationship to Fatigue Strength written by Bertil Jonsson and published by Springer. This book was released on 2016-04-13 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents guidelines on quantitative and qualitative measures of the geometric features and imperfections of welds to ensure that it meets the fatigue strength requirements laid out in the recommendations of the IIW (International Institute of Welding). Welds that satisfy these quality criteria can be assessed in accordance with existing IIW recommendations based on nominal stress, structural stress, notch stress or linear fracture mechanics. Further, the book defines more restrictive acceptance criteria based on weld geometry features and imperfections with increased fatigue strength. Fatigue strength for these welds is defined as S-N curves expressed in terms of nominal applied stress or hot spot stress. Where appropriate, reference is made to existing quality systems for welds.In addition to the acceptance criteria and fatigue assessment curves, the book also provides guidance on their inspection and quality control. The successful implementation of these methods depends on adequate training for operators and inspectors alike. As such, the publication of the present IIW Recommendations is intended to encourage the production of appropriate training aids and guidelines for educating, training and certifying operators and inspectors.

Download or read book Fatigue Assessment of Welded Joints by Local Approaches written by Dieter Radaj and published by Woodhead Publishing. This book was released on 1998 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Recommendations for Fatigue Design of Welded Joints and Components written by A. F. Hobbacher and published by Springer. This book was released on 2015-12-23 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a basis for the design and analysis of welded components that are subjected to fluctuating forces, to avoid failure by fatigue. It is also a valuable resource for those on boards or commissions who are establishing fatigue design codes. For maximum benefit, readers should already have a working knowledge of the basics of fatigue and fracture mechanics. The purpose of designing a structure taking into consideration the limit state for fatigue damage is to ensure that the performance is satisfactory during the design life and that the survival probability is acceptable. The latter is achieved by the use of appropriate partial safety factors. This document has been prepared as the result of an initiative by Commissions XIII and XV of the International Institute of Welding (IIW).

Download or read book Assessment of Field Surface Treatments for Prolonging the Life of Steel Welded Joints Subjected to Fatigue Loading written by Mark S. Van Sickle and published by . This book was released on 2013 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: In heavy truck applications welds are commonly used to join structural steel components that are subjected to cyclical loads. In cases where a weld fatigue issue is discovered in the field the customer desires to have low-cost methods to increase service life. This research was initiated to recommend a process for treating welded joints on heavy trucks that can be accomplished in the field with limited manufacturing resources. Surface peening is a cold working process that introduces beneficial residual compressive stresses in the surface of a work piece. Two different surface peening processes were evaluated for their ability to increase fatigue life in fillet welds. These processes were hammer peening and rotary flap peening. T-shaped fillet weld test samples were fabricated and subjected to cyclic loading in three configurations; as-welded, welded and hammer peened, and welded and flap peened. Metallographic inspection was used to further evaluate the test samples following fatigue testing. Fatigue life estimation methods were considered based on both experimentally measured strain data and stress/strain results obtained through the use of finite element methods. Stress-life analyses based on weld classifications established by British Standard BS7608 were conducted. Strain-life analyses based on the use of A36 steel fatigue properties with the application of a fatigue notch factor were also conducted.

Download or read book IIW Recommendations for the Fatigue Assessment of Welded Structures By Notch Stress Analysis written by W Fricke and published by Woodhead Publishing. This book was released on 2012-10-22 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The notch stress approach for fatigue assessment of welded joints is based on the highest elastic stress at the weld toe or root. In order to avoid arbitrary or infinite stress results, a rounded shape with a reference radius instead of the actual sharp toe or root is usually assumed. IIW recommendations for the fatigue assessment of welded structures by notch stress analysis reviews different proposals for reference radii together with associated S-N curves. Detailed recommendations are given for the numerical analysis of notch stress by the finite or boundary element method. Several aspects are discussed, such as the structural weakening by keyhole-shaped notches and the consideration of multiaxial stress states. Appropriate S-N curves are presented for the assessment of the fatigue strength of different materials. Finally, four examples illustrate the application of the approach as well as the variety of structures which can be analysed and the range of results that can be obtained from different models. Provides detailed recommendations for the number analysis of notch stress by the finite or boundary element method Discusses structural weakening by keyhole-shaped notches and the consideration of multiaxial stress states Provides four comprehensive examples, illustrating the variety of structures which can be analysed and the range of results that can be obtained from different models