Numerical simulation on residual stresses of stainless steel SS-304 thin welded pipe

Abstract

The major concern in the high tech industries like oil and petroleum industries, automobiles, aeronautical, and nuclear power plants is the control of the defects like distortion in the welded joints and residual stresses occur due to arc welding on the circumferential joints of the thin pipes. Three-dimensional non-linear thermal and thermomechanical numerical simulations are conducted for the tungsten inert gas welding process of SS-304 stainless steel pipes. In this article, numerical analysis of the distribution of the temperature and the welding residual stress fields induced after the welding is done. Study on the effect of the welding heat input by varying the welding parameters (like welding current and welding speed) based on finite element simulations is conduit to examine the results on the residual stresses which is also called as the ‘locked-in’ stresses. The precision of the finite element model is validated for the welding residual stresses. The intention of this study is to provide the information to verify the validity of ongoing process circumferential manufacturing technology for thin-walled pipes, so to avoid the failure of these kinds of structures which are in service because of these intrinsic stresses.