Evaluation of Welding Residual Stress in GTAW Tubular Welds

The purpose of this study is to evaluate the welding residual stress of the tubular welds with welding pass and restraint conditions. For it, a heat input model for GTA (Gas Tungsten Arc) pulse welding was developed by comparing the molten pool shape and the temperature history in way of the weld obtained by FEA and experiment. The validation of evaluation procedure for welding residual stress with 3 dimensional thermo-mechanical analysis was also verified by comparing with measured results in the simple tubular weld. With the heat input model for GTA pulse welding and FEA procedure, the comprehensive 3 dimensional FEA were performed to evaluate the effect of the welding pass and restraint conditions on the distribution of welding residual stress and distortion in the actual tubular welds.