Effect of simulated welding parameters on pipe girth weld residual stresses

A two-dimensional axial-symmetric finite-element model of welding residual stresses of thick-wall pipe has been proposed based on the theory of thermal-elastoplasticity.Using ANSYS finite-element code, the effect of three groups of welding parameter on girth weld residual stresses of pipe is analyzed.The temperature correlation of thermal physical property parameter with mechanical property parameter is considered during the simulation.The results show that both the axial stresses and the hoop stresses are tensile stress in the pipe inner surface weld and near weld section, but they are compression stress in the pipe outer surface weld and near weld section.The stress value near the inner surface is higher than the one of the outer surface in the joint;the maximal value of residual stresses appears in the certain distance beneath exterior surface of the pipe, and the value is close to the yield stress of base metal.The size of plastic deformation zone increases with the increase of heat input while peak value of residual stresses change little.