Influence of lumping passes on calculation accuracy and efficiency of welding residual stress of thick-plate butt joint in boiling water reactor

Abstract

An advanced computing approach based on commercial software ABAQUS was developed to calculate the welding residual stress in a multi-pass butt-welded joint. An equal-density instantaneous heat source model and the lumping-pass method were used to improve the calculation efficiency. According to the numerical and experimental results, the influence of lumping-pass patterns and two-dimensional (2D) model on the calculation accuracy and efficiency of welding residual stress were investigated. The results show that the lumping-pass method can greatly shorten the calculation time. Lumping weld passes along the thickness direction has little effect on the calculation accuracy of welding residual stress while lumping weld passes along the width direction will cause a larger error in calculation accuracy. Using the 2D model can save 97% of the calculation time and is more effective than the lumping-pass method based on 3D model, but it has a certain influence on the calculation accuracy of welding residual stress.