A framework for estimating residual stress profile in seam welded pipe and vessel components Part II: Outside of weld region

Abstract

Part I of this study has identified two key parameters (r/t ratio and characteristic heat input Qˆ) that dominate important through-thickness residual stress distribution characteristics, with which a residual stress profile estimation scheme has been developed for weld region, i.e., at weld centerline and weld toe. In Part II, we present an analytical model for achieving residual stress profile estimation for through-thickness sections away from the weld region in seam welded pipe and vessel components. A curved beam bending theory based model is analytically constructed through an assembly of two parts: One is weld fusion zone region and the other is the rest of the component section along circumferential direction. The final assembly of the two parts leads to a closed form solution to both axial (longitudinal) and hoop (transverse) residual stress components as a function of circumferential angular position away from weld toe. The effectiveness of the full-field residual stress estimation scheme is demonstrated by comparing with finite element modeling results over a broad range of weld geometries and welding conditions. The present development should provide a consistent and effective means for estimating through-thickness residual stress profile as a continuous function of pipe geometry and welding heat input.