Analytical study of the effect of excessive loading on welding residual stress and crack growth near piping welds

Katsuyama, Jinya  ; Onizawa, Kunio 

Welding residual stress, which is one of the most important factors of stress corrosion cracking (SCC) growth in pressure boundary piping, affected by excessive loading such as an earthquake has been evaluated by axisymmetric thermo-elastic-plastic analysis based on finite element method (FEM). Several loading of prescribed displacement for piping butt-welds have been applied in axial direction by varying the loading conditions of maximum value and wave form after welding simulation. Higher excessive loading causes higher relaxation of welding residual stress near piping welds. As the result, SCC growth rate decrease by increasing of prescribed displacement.