Effects of the weld groove shape and geometry on residual stresses in dissimilar butt-welded pipes

摘要

The thermo mechanical behavior of the welding process was analyzed using the finite element technique to determine the residual stress magnitude and distribution in butt-welded pipes. An efficient user subroutine was developed in a finite element model to consider the effects of phase transformation in the analysis. The calculated results verified using the determined data presented by Deng for similar weld joints and measured data by the hole drilling technique for dissimilar weld joint. Good correspondence between the finite element results and experimental data infers that the computational procedure developed in this study is an effective method for residual stress prediction in dissimilar welded joints. The effects of pipe wall-thickness, weld groove angle and root opening distance on welding residual stresses in dissimilar butt-welded pipes were studied using the prepared finite element model. It is observed that the pipe wall-thickness has important influences on the residual stress magnitude and distribution. Meaningful influences from weld groove angles and root opening distances are observed on the axial residual stresses in the ferritic side.