Modeling of weld residual stresses in core shroud structures

Citation
Jm. Zhang et al., Modeling of weld residual stresses in core shroud structures, NUCL ENG DE, 195(2), 2000, pp. 171-187
Citations number
33
Categorie Soggetti
Nuclear Emgineering
Journal title
NUCLEAR ENGINEERING AND DESIGN
ISSN journal
00295493 → ACNP
Volume
195
Issue
2
Year of publication
2000
Pages
171 - 187
Database
ISI
SICI code
0029-5493(200002)195:2<171:MOWRSI>2.0.ZU;2-W
Abstract
This paper presents a computational model to predict residual stresses in a girth weld (H4) of a BWR core shroud. The H4 weld is a multi-pass submerge d-are weld that joins two type 304 austenitic stainless steel cylinders. An axisymmetric solid element model was used to characterize the detailed evo lution of residual stresses in the H4 weld. In the analysis, a series of ad vanced weld modeling techniques were used to address some specific welding- related issues, such as material melting/re-melting and history annihilatio n. In addition, a 3-D shell element analysis was performed to quantify spec imen removal effects on residual stress measurements based on a sub-structu ral specimen from a core shroud. The predicted residual stresses in the H4 weld were used as the crack driving force for the subsequent analysis of st ress corrosion cracking in the H4 weld. The crack growth behavior was inves tigated using an advanced finite element alternating method (FEAM). Stress intensity factors were calculated for both axisymmetric circumferential (36 0 degrees) and circumferential surface cracks. The analysis results obtaine d from these studies shed light on the residual stress characteristics in c ore shroud weldments and the effects of residual stresses on stress corrosi on cracking behavior. (C) 2000 Elsevier Science S.A. All rights reserved.