The problem of the welding residual stresses always draw wide attention.The distribution and magnitude of residual stresses
relate to several factors such as thermal source,joint shape and material property,etc.In this paper,circumferential bett-welding of SAF2205
duplex stainless steel pipe was simulated numerically based on a non-linear thermo-mechanical finite element-analysis.The
residual stress distributions were obtained.The axial and the hoop residual stresses at the weld and weld vicinity on inner surface of pipes are tensile,while those on outer surface of pipes are compressive and the hoop one is tensil.Effects of weld line energy,ratio of inner radius to wall thickness and multi-pass weld on residual stresses were further investigated.The results show that the line energy has small influence upon the residual stresses within practical applications.The thicker walled pipes have more residual axial stress and a larger zone of tensile stress.Compared with single pass,the peak value of residual stress by multi-pass welding decreases to different extent.