The safe-end length effect on welding residual stresses in dissimilar metal welds of surge nozzles

The effects of safe-end length and kinematic boundary conditions during welding on weld residual stresses in dissimilar metal welds are systematically investigated using finite element analyses for typical pressurized water reactor surge nozzle configurations. The study is generalized by idealizing complex nozzle geometries as straight pipes with two welds. The impact of these variables on axial residual stresses at inner surface is examined, since these are of most concern for primary water stress corrosion cracking. Possible mechanisms controlling the development of welding residual stresses are used to qualitatively explain the predicted behavior.