Welding Stress Redistribution in a Butt-Welded Pipe During Later Mechanical and Thermal Loadings

Stress redistribution in a butt-welded pipe during later mechanical and thermal treatments is studied numerically by use of a thermoelastoplastic FE-model. It is proposed that the influence of the welding process on the redistribution can be modeled using a simplified approach. Here the welding residual stress field is simulated with an equivalent radial line load. Two standard treatments, one mechanical and one thermal, are studied with this simplified approach. Both treatments are performed after the welding is completed. The calculations show that both treatments can be used to turn (detrimental) tensile welding residual axial stresses on the inner surface at the weld into compressive ones.