Recent Advances in Design and Usage of Pressure Vessels and Piping Components [1 ed.] 9781614701491, 9781613249789

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Copyright © 2011. Nova Science Publishers, Incorporated. All rights reserved. Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

Copyright © 2011. Nova Science Publishers, Incorporated. All rights reserved. Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

MECHANICAL ENGINEERING THEORY AND APPLICATIONS

Copyright © 2011. Nova Science Publishers, Incorporated. All rights reserved.

RECENT ADVANCES IN DESIGN AND USAGE OF PRESSURE VESSELS AND PIPING COMPONENTS

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Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

MECHANICAL ENGINEERING THEORY AND APPLICATIONS

RECENT ADVANCES IN DESIGN AND USAGE OF PRESSURE VESSELS AND PIPING COMPONENTS

MAHENDRA KUMAR SAMAL Copyright © 2011. Nova Science Publishers, Incorporated. All rights reserved.

EDITOR

Nova Science Publishers, Inc. New York

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

Copyright © 2012 by Nova Science Publishers, Inc. All rights reserved. No part of this book may be reproduced, stored in a retrieval system or transmitted in any form or by any means: electronic, electrostatic, magnetic, tape, mechanical photocopying, recording or otherwise without the written permission of the Publisher. For permission to use material from this book please contact us: Telephone 631-231-7269; Fax 631-231-8175 Web Site: http://www.novapublishers.com NOTICE TO THE READER The Publisher has taken reasonable care in the preparation of this book, but makes no expressed or implied warranty of any kind and assumes no responsibility for any errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of information contained in this book. The Publisher shall not be liable for any special, consequential, or exemplary damages resulting, in whole or in part, from the readers‘ use of, or reliance upon, this material. Any parts of this book based on government reports are so indicated and copyright is claimed for those parts to the extent applicable to compilations of such works.

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Independent verification should be sought for any data, advice or recommendations contained in this book. In addition, no responsibility is assumed by the publisher for any injury and/or damage to persons or property arising from any methods, products, instructions, ideas or otherwise contained in this publication. This publication is designed to provide accurate and authoritative information with regard to the subject matter covered herein. It is sold with the clear understanding that the Publisher is not engaged in rendering legal or any other professional services. If legal or any other expert assistance is required, the services of a competent person should be sought. FROM A DECLARATION OF PARTICIPANTS JOINTLY ADOPTED BY A COMMITTEE OF THE AMERICAN BAR ASSOCIATION AND A COMMITTEE OF PUBLISHERS. Additional color graphics may be available in the e-book version of this book. LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA

ISBN: H%RRN

Published by Nova Science Publishers, Inc. † New York

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

CONTENTS Preface Chapter 1

Global Approach Versus Local Approach for Cleavage Crack Arrest C. Berdin, A. Dahl and D. Moinereau

Chapter 2

On the Phenomenon of Delayed Hydride Cracking in Zircaloy Pressure Tubes Used in Nuclear Industry G. Sanyal and M. K. Samal

Chapter 3

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vii

Application of Glass Pressure Vessel in the Formulation of Strategic Products and Investigation of some under-Pressure Reactions Hossein Fakhraian, Hashem Kamranpay, Saman Shams, Morteza Alihosseini, and Ebrahim Choobdari

Chapter 4

Pressure Vessels Design Using FEM Softwares M. Javed Hyder

Chapter 5

A Multifactorial Approach to the Blood Pressure Control. The Role of the Asymmetrical Organization of the Nervous System M. Ramírez, I. Banegas, A. B. Segarra, R. Wangesteen,M. de Gasparo, F. Vives, F. Alba, M Ruiz-Bailen and I Prieto

Chapter 6

Chapter 7

Chapter 8

A Practical FEA Crack Growth in the Irradiation Damaged Pressure Vessels (Tubes) by Using a Material Model of Gurson Type as a Constitutive Material Law Stefan Mehedinteanu Aspects of Structural Integrity Assessment of Pressure Vessels and Piping Components in the Ductile Fracture Regime M. K. Samal, M. Seidenfuss and E. Roos Predictive Models for Simulation of Statistical Aspects of Fracture Behaviour of Pressure Vessels and Piping Components in the Ductile-to-Brittle Transition Regime and their Experimental Validation M. K. Samal, M. Seidenfuss, E. Roos, and J. K. Chakravartty

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

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vi Chapter 9

Contents Life Estimation of Pressure Vessels and Piping Components Operating in the Creep Regime Due to Sustained as Well as Fluctuating Loading Conditions Mahendra Kumar Samal

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Index

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207 237

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PREFACE Pressure vessels and piping components have been the backbone of industrial development. Their presence is inevitable in various types of power plants (e.g., fossil fuelled and nuclear power plants), chemical and process plants (e.g., chemical reactors, refineries etc.). In simple terms, a pressure vessel can be defined as any container of fluid with a pressure differential between the outside and the inside atmoshphere of the container. Even the tanks used for storage of liquids (e.g., water, petroleum and petroleum products etc.) can be classified as pressure vessels where the pressure is due to the height of the liquid column. The pipelines are a special form of pressure vessels where the pressure is because of the pressurized flowing fluid. The fluid inside the vessel may also undergo a change in the state as in the case of steam boilers, or may combine with other reagents as in the case of a chemical reactor. Pressure vessels often have a combination of high pressures together with high temperature operating conditions, and in some cases, they contain flammable fluids or highly radioactive materials. Because of such hazards, it is imperative that the design of the pressure vessels should ensure the states of no-leakage or leak-before-catastrophic break (e.g., LBB conditions in the case of nuclear pressure vessels). In addition, these vessels have to be designed carefully to cope with the operating temperature and pressure. It may be noted that the rupture of a pressure vessel has a potential to cause extensive physical injury to operating personnel and property damage. Plant safety and integrity are of fundamental concern in pressure vessel design and these depend upon the adequacy of design codes followed by the designers. Various organizations such as American Society of Mechanical Engineers (ASME) and American Petroleum Institute (API) prescribe rules for design, construction, non-destructive examination and in-service inspection of pressure vessels. Both the concepts of ‗design by rule‘ and ‗design by analysis‘ are followed. Design by analysis philosophy is more prevalent in nuclear industry (where ASME Boiler and Pressure Vessels code, Section-III is used), whereas for other industries, ASME Boiler and Pressure Vessels code, Section-VIII, Division-I design rules are used. The design by analysis philosophy can remove overconservatism in design and make the design safer by providing the designer with more information regarding the wide variety of deformation and failure modes of the structure including plasticity, buckling, fatigue, creep etc. With the advent of high speed computers, it is now possible to carry out a detailed threedimensional finite analysis of components with complex geometry, loading and boundary

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Mahendra Kumar Samal

conditions with both elastic and elastic-plastic material constitutive models (to know the accurate states of stress and temperature profile). The traditional plate and shell elements are being replaced by 3D solid elements in recent analysis by the FE analysts worldwide. This has brought out a revolution in the design by analysis philosophy of pressure vessels where the industries compete to make the pressurized components safer, more economic, reliable and more efficient. In view of many recent developments in the design and usage of pressure vessels and piping components, this edited volume aims at presenting the works of various authors worldwide in diverse areas pertaining to this central theme. This volume contains nine different chapters with a wide range of topics ranging from design of pressure vessel using advanced finite element softwares to the application of material damage models to predict crack growth and crack-arrest in pressure vessels in various types of loading conditions including the postulated design-basis accident scenarios. Chapter 1 discusses the experimental and computational studies of crack propagation resistance of a low-alloy bainitic steel which is widely used in the manufacturing of nuclear pressure vessels. The authors have carried out thermal shock experiments to study the initiation, propagation and arrest of an initial crack in structures such as discs. It was shown that the crack growth and speed are largely influenced by the interactions of structural vibrations with the growing crack as the stress field (due to actual loading) gets modified due to the effect of stress wave propagation. The authors use elastic-plastic and transient elasticvisco-plastic finite element analysis for prediction of the stress field ahead of the crack. The crack growth is modeled using FE node release technique. The two nodes, which are intact ahead of the crack-tip, are released when a specific critical condition is satisfied. A critical temperature-dependent stress criterion was used by the authors for the crack growth analysis. The authors were able to successfully predict the crack arrest front and the results compare very well with experimental data. This chapter is an important contribution in the safety analysis of critical plant components, especially the nuclear vessels (in pressurized and boiling water reactors), which are usually subjected to pressurized thermal shock conditions in accident scenarios. Chapter 2 presents the phenomenon of delayed hydride cracking which are observed in pressure tubes of CANDU type nuclear reactors. The Indian pressurized heavy water reactors (PHWR) also use Zirconium alloy pressure tubes. These are horizontal tubes which contain the nuclear fuel bundles and the pressurized fluid (i.e., heavy water) flows through these tubes to remove the heat released during the nuclear fission reaction from these fuel bundles. However, the life of these tubular components is limited because of the onset of delayed hydride cracking due to interaction of these alloys with the coolant in the presence of stresses. In this chapter, the mechanism of delayed hydride cracking (DHC) has been discussed and works carried out by different researchers have been reviewed. The importance of developing suitable mathematical models to predict the DHC, their advantages and disadvantages has been highlighted. Chapter 3 presents the application of glass pressure vessel in the formulation of strategic products such as sticky foam, decontamination foam, explosive foam and medicinal aerosols etc. The use of glass pressure vessels to obtain a high quality final product has been described. The authors have also carried out an optimization of the production process using a specific shape of these glass pressure vessels.

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

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Preface

ix

Chapter 4 is extremely important for practising engineers, designers and analysts in various types of industries which use pressure vessels. This article discusses the methodology of designing pressure vessels using the commercial finite element softwares. Methodologies for achieving finite element mesh-independent results are discussed by the authors. They have also discussed the procedure to be adopted to ensure minimal probability of failure during the design of pressure vessel. A new idea of designing a pressure vessel based on an interactive procedure has been presented in this chapter. Chapter 5 presents a multi-factorial approach to the blood pressure control in the nervous system. The importance of various enzymatic factors and the role of the central/peripheral asymmetries in the nervous system towards pressurization of blood vessels are highlighted in this article. Chapter 6 presents a computational method for prediction of crack growth in irradiated pressure vessel steels. The Gurson-Tvergaard-Needleman‘s (GTN) model has been used by the authors in the finite element analysis. The use of open source finite element code WARP3D has been discussed at length by the authors. This type of material constitutive model is very important for a reliable safety analysis of structures and components (with various types of postulated cracks) under wide varying loading conditions. The model uses mathematical models for microscopic processes of void nucleation, growth and coalescence in ductile materials to predict the initiation and propagation of crack. The model parameters are truly material properties and hence, these are easily transferable from laboratory specimens to actual components. The parameters can be determined from laboratory tests of standard fracture mechanics specimens. The authors highlight the convenience of using the FE code WARP3D for a reliable safety analysis and this chapter is of high importance to the new and practising FE analysts in industry. Chapter 7 presents various aspects of structural integrity assessment of pressure vessels and piping components in the ductile fracture regime of materials. In this chapter, the recent contribution of the authors for simulation of fracture resistance behaviour of different types of specimens and components using Rousselier‘s and Gurson-Tvergaard-Needleman‘s damage mechanics model have been described in detail. The limitations of the local approaches for ductile fracture have been outlined. The nonlocal formulation based on the coupling of the nonlocal damage diffusion equation to the mechanical equilibrium equation has been discussed. The aspects of implementation of the new model in a finite element framework have been described. Several example problems have been solved in order to prove the meshindependent nature of the finite element solutions. Experiments have been conducted on several types of specimens and components and results of numerical simulation have been compared with those of experiment. The ability of the model to reproduce the size, geometry and loading effects on ductility and fracture resistance behavior of different types of pressure vessel steels have been demonstrated through solved examples. Chapter 8 presents the recent work on the development of a combined ductile and cleavage fracture model for simulation of fracture behaviour in the ductile to brittle transition temperature (DBTT) regime of ferritic steels which are widely used in the manufacture of vessels in nculear and fossil power industries. The finite element implementation aspect of the model is discussed. Several experimental results (i.e., fracture tests) involving different size, shapes of fracture mechanics specimens, different kinds of materials etc. have been presented and these data have been compared with the predicted results of the finite element model.

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Mahendra Kumar Samal

Evaluation of damage due to creep and fatigue loading conditions in critical power plant components is of significant interest to plant operators and engineers involved in life estimation and life extension of these components. However, accurate life estimation requires significant amount of data relating to loading history and material properties at several critical locations. It is also essential to understand the micro-mechanism of the material degradation process (due to creep and fatigue) and the consequent crack nucleation or creep cavitation phases in the material. This will help in developing a reliable predictive model to estimate the remaining life of the components. Traditional life estimation techniques rely on use of nondestructive evaluation methods to detect presence of any significant defect in these components and use code-based rules to estimate the remaining life. In this process, it is difficult to incorporate the effect of prior operational history on the evolution of damage in the material point. Again, the state of micro-structural degradation is also not quantified and hence these are usually not considered explicitly for life estimation. In the Chapter-9, the authors discuss an online damage monitoring system that has been combined with quantitative metallography procedure (conducted at critical sites) to evaluate the damage due to creep and fatigue in power plant components. The details of the methodology used by the online damage monitoring system are discussed in this chapter. Hence, it can be noted that a wide range of topics has been presented in this edited collection which will go a long way in helping the practising engineers, plant operators, designers and analysts to achieve their goal of a safe, reliable and economic design of the pressure vessel and piping components and stay abreast with the latest developments in this interesting area of research. Finally, I would like to thank all the contributors to this volume for their support in bringing up this volume into the current shape. The authors have diligently adhered to the time-line of submission of the manuscripts despite their other busy schedule of teaching and research. The support of the publication team at Nova Science Publishers has been overwhelming. They have been very helpful at each step of the preparation of this edited volume. I am thankful to the authorities at Bhabha Atomic Research Centre (BARC), Mumbai, India for supporting my initiative to go through this editing process of a volume which is of considerable importance to various industries especially the nuclear and fossilfuelled power plants. I am grateful to my colleagues for their encouragement and support during the course of preparation of various chapters and the editing work. I am thankful to my wife, my son and my parents for their endless love and support to this initiative.

March 2011

Mahendra Kumar Samal Bhabha Atomic Research Centre Trombay, Mumbai-400085, India

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

In: Recent Advances in Design and Usage of Pressure Vessels… ISBN: 978-1-61324-978-9 Editor: Mahendra Kumar Samal, pp. 1-29 © 2012 Nova Science Publishers, Inc.

Chapter 1

GLOBAL APPROACH VERSUS LOCAL APPROACH FOR CLEAVAGE CRACK ARREST C. Berdin,1,2 A. Dahl2,3 and D. Moinereau3 1

Université Paris-Sud 11, ICMMO/LEMHE, CNRS UMR 8182, 91405 Orsay cedex 2 Laboratoire MSSMat, CNRS UMR 8579, Ecole Centrale Paris, Grande Voie des Vignes, 92295 Châtenay Malabry cedex 3 EDF, Centre des Renardières, Ecuelles, 77818 Moret sur Loing cedex

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ABSTRACT The crack propagation resistance of a low alloy bainitic steel used for nuclear pressure vessels was studied. Thermal shock experiments were carried out on precracked discs. These tests were analyzed using the finite element method according to various assumptions, from elastic-static to full transient elastic-viscoplastic analysis. The crack propagation was first modeled using node release technique. It was shown that there is a large influence of dynamics (on crack propagation) due to interactions with structural vibrations. The arrest fracture toughness as defined by the standard procedure was computed: influence of initial crack length was evidenced, whereas the thickness of the specimen does not modify the results. Local criterion was then applied in order to avoid geometrical effect. A critical stress criterion depending on temperature was implemented in a finite element code, and the thermal shock experiments were modeled with full transient analysis. 2D model showed that such a fracture criterion is able to predict crack length at arrest for different conditions of the thermal shock tests. A combined 2D and 3D model allowed to show that the criterion correctly predict the shape of the crack arrest front.

NOMENCLATURE KI KIc KIa

stress intensity factor initiation fracture toughness arrest fracture toughness

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

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C. Berdin, A. Dahl and D.Moinereau

K Idyn

dynamic stress intensity factor

K Ista

static stress intensity factor

KIu w a a0 amin amax asim

displacement stress intensity factor width of the specimen crack length initial crack length final crack length measured on the specimen side final crack length measured at the center of the specimen predicted crack length at arrest crack speed temperature of the crack tip at crack initiation temperature of the crack tip at crack arrest temperature von Mises equivalent stress von Mises equivalent plastic strain rate

a T0 Tf T

eq

p  Cp

 

cd cs

bulk density specific heat capacity thermal conductivity thermal expansion coefficient dilatational wave speed shear wave speed

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ABBREVIATIONS CCA LOCA RTNDT COD DTSE

compact crack arrest loss of coolant accident nil ductility room temperature crack opening displacement thermal shock experiment on disc

1. INTRODUCTION For structural integrity studies, crack arrest concept can serve as a complement to classical crack initiation assessment (Burdekin et al., 1999). The arrest toughness KIa, defined by Irwin, thereby supplements that of initiation toughness, KIc. Various tests may be used to characterize crack propagation resistance. The ASTM standard proposes the Compact Crack Arrest (CCA) test, which consists of propagating a crack under a constant crack opening displacement (COD). Indeed it is the minimum value of the COD which is constant since the displacement is controlled by unilateral contact. The arrest toughness KIa , like the initiation toughness KIc, is then determined by an elastic-static analysis. However, it is recognized that the use of KIa as a material parameter leads to more or less conservative prediction depending on different conditions: experimental results showed a

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

Global Approach Versus Local Approach for Cleavage Crack Arrest

3

dependence of KIa on the maximum crack speed, on crack jump but also on specimen geometry and (Kalthoff et al., 1977) ligament loading (Smith 1994). These dependencies are often explained by dynamic effects coming from rapid crack propagation, since crack speed is a finite fraction of wave speed within the material (between 20% and 35% of the Rayleigh wave speed for cleavage cracks in steels). Experimental measurement of the dynamic stress intensity factor, K Idyn showed that this value can be lower or higher than the static stress intensity factor K Ista (Kalthoff et al., 1977). At the end of the crack propagation, K Idyn is higher than K Ista . This is currently explained by interactions between elastic waves (emitted by the crack tip and reflected by the specimen sides) and the crack tip itself (Kalthoff et al., 1977,Rosakis at al., 1984). Interactions between the crack propagation and the global vibrations of the specimen are also evoked (Hahn et al.,

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1976, Bonenberger et al., 1995) since oscillations K Idyn are observed after the crack arrest. The application of the global approach of dynamic fracture seems therefore to be required. Nevertheless, this approach is mainly based on analyses of semi-infinite body, i.e. without vibration, so its application to determine the arrest fracture toughness is also questionable because of the scale effect of structural dynamics. To overcome this difficulty, a local crack arrest criterion can be proposed, following the local approach to cleavage fracture. Arguing that final fracture by cleavage is induced by the extension of a Griffith like defect, a critical stress criterion was proposed by Ritchie et al. (1973) to predict the initiation fracture toughness: the RKR criterion. This criterion supposes that the fracture by cleavage occurs as soon as the macroscopic opening stress ahead of the crack tip is higher than a critical stress over a critical distance. The critical stress was related to the Griffith like defect size and the critical distance was related to the probability of finding such a critical defect ahead of the crack tip. This criterion was extended to any geometry through e.g. the Beremin model (Beremin, 1983) or the WST model (Wallin et al., 1984). The concept of critical stress has been recently used for cleavage crack propagation and arrest by Bratov and Petrov (2007), Berdin et al. (2008) and Prabel et al. (2008). In this chapter, we gathered the results of studies on crack arrest of a bainitic nuclear pressure vessel steel (Hajjaj et al., 2008, Berdin et al., 2008, Dahl et al., 2009) that are completed by results with specimens of different thicknesses and by the simulations of the whole database. Experimental results are presented, analysed by the global approach to static fracture, then by the global approach of dynamic fracture, and finally by a local approach to dynamic crack propagation and crack arrest. These studies are based on thermal shock experiments on precracked discs which simulate the thermal loading conditions occurring in nuclear pressure vessels during a transient loading, such as the loss of coolant accident (LOCA). Initial crack length and thickness effect are studied. The second section is dedicated to the presentation of the material, the experimental procedure and to some rough results. Thermo-mechanical analyses using the finite element method are therefore performed and presented in the third section, in order to compute the stress intensity factor and to determine the toughness. The experiments are first interpreted in static terms as required by the ASTM standard. Full transient dynamic analyses are then performed, accounting for the elastic-viscoplastic behavior of the material with temperature dependence of the flow stress. The influence of the crack kinetics on the dynamic fracture toughness assessment is evidenced by different assumptions. Finally, a

Recent Advances in Design and Usage of Pressure Vessels and Piping Components, edited by Mahendra Kumar Samal, Nova Science Publishers,

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fourth section is devoted to the application of a local approach to crack propagation and arrest: a critical stress criterion is applied in order to simulate the crack propagation and arrest. This study is carried out with 2D finite element model, allowing the simulation of number of tests. 3D modeling is then carried out in order to predict the shape of the crack arrest front.

2. MATERIAL AND EXPERIMENTS 2.1. Material The material is a french 18MND5 steel (equivalent to the American ASTM Standard A533-B) extracted from a heavy section of rolled sheet. Its composition in weight% is 0.19C, 1.5Mn 0.66Ni, 0.48Mo, 0.004P, 250°C, cracking stopped because the low hydrogen concentration,