Effects of Welded Pipe-cutting on the Residual Stress Re-Distribution and Engineering Critical Assessment

Welded rolled up steel pipe plates undergo more roundness deformation than seamless pipes. The main reason is that the existing residual stress after welding was re-distributed by the cutting process. The objective of this research is to investigate the effect of the constraint on the cutting process through finite element analysis (FEA) to minimize deformation. To include the effect of the cutting simulation, the external constraint was used as the mechanical restraint, and a welded pipe without constraints was used for comparison purposes. The results show that the cutting deformation and residual stress were both significantly reduced under the effect of external constraints. Moreover, the method of reducing conservatism in engineering critical assessment (ECA) was proposed using residual stress re-distribution.