Effect of the welding sequence in the circumferential direction on residual stress distribution in a thin-walled pipe weld

Abstract

This paper presents a three-dimensional (3D) finite element (FE) analysis to investigate the influence of the welding sequence in the circumferential direction on residual stress distribution in a thin-walled carbon steel pipe weld. Single-pass butt-welded joint geometry with an outer diameter of 300 mm and a thickness of 7 mm is studied. A 3D uncoupled thermomechanical FE model is developed in order to incorporate the 3D features and the welding sequence in the steel pipe weld. The thermomechanical model is described and details of the analysis methodology are provided. Six different welding sequences in the circumferential direction considering actual welding circumstances are employed, and it is shown that the residual stresses within and near the weld deposit are generally influenced by the welding sequence. The variations are not large, however, thus the benefits arising from the change of the residual stresses in and around the weld area are offset by the potential drawback of the several stop and start positions, with the special risk of weld defects.