Residual Stress Fields due to Varying Tack Welds Orientation in Circumferentially Welded Thin-Walled Cylinders

Abstract

The local, nonuniform heating and subsequent cooling during the welding processes causes complex thermal stress/strain fields to develop that finally leads to residual stresses, distortions, and their adverse consequences. Residual stresses are of prime concern to the industries producing weld-integrated structures around the globe because of their obvious potential to cause dimensional instability in welded structures, contribute to premature fracture/failure, along with the significant reduction in fatigue strength and in-service performance of the welded structures. Arc welding with single or multiple weld runs is an appropriate and cost effective joining method to produce high-strength structures in these industries. A multifield interaction in arc welding process makes it a complex manufacturing process. A number of geometric and process parameters are contributing to significant stress levels in arc-welded structures. In the present analysis, parametric studies are conducted for the effects of a critical geometric parameter, that is, tack weld on the corresponding residual stress fields in circumferentially welded thin-walled cylinders. Tack welds offer a considerable resistance to the shrinkage and the orientation, and size of tacks can alter altogether the stress patterns within the weldments. Hence, a critical analysis for the effects of tack weld orientation is desirable.