Finite Element Welding Residual Stress Analysis of CRDM Penetration Nozzles

Abstract

This paper investigates numerically welding residual stress distributions of a tube with J-groove weld in control rod drive mechanisms of a pressurized nuclear reactor vessel. Parametric study is performed for the effect of the tube location, tube dimensions and material's yield strength. It is found that residual stresses increase with increasing the inclination angle of the tube, and the up-hill side is the most critical. For thicker tube, residual stresses decrease. For material's yield strength, both axial and hoop residual stresses tend to increase with increasing the yield strength of Alloy 600. Furthermore, axial stresses tend to increase with increasing yield strength of Alloys 82/182.

Numerical Simulation of the Effect of Fusion Welding Processes on Residual Stress in Stainless Steel Pipe Weld Joints Used in Fast Reactors

“…Residual stress decreases with the thickness of the tubes. Axial and hoop residual stresses tend to increase when the yield strength of a material increase [41]. The welding process significantly impacts the residual stress on the pipe's inner wall, whereas the residual stress on the pipe's outer wall is less affected.…”