An Experimental and Numerical Modelling for Submerged Arc Welding

FRAMATOME has used the numerical simulation for many years now for a better understanding of the phenomena involved during manufacturing process, and more specifically welding operations [1][2][3][4][5][6]. Numerical simulation allows a better prediction and understanding of the distortions and residual stresses induced during the welding process. This paper deals with the numerical welding simulation of a SAW mock-up (Submerged Arc Welding). A specific mock-up joining two 18MND5 ferritic steel grade plates has been made. The aim of this mock-up is to be representative of a circular welding of two shells of a steam generator, which dimensions are too large to be used as a mock-up. The narrow groove (90 mm depth) is filled by a SAW welding process using a multipass methodology (29 layers). To monitor the welding conditions as precisely as possible, temperature gradient within the mock-up base material, interpass temperature, and the outline evolution of the chamfer are recorded bead after bead during the manufacturing process. The welding parameters (current, tension, welding time) are also recorded during the welding of each bead. To complete the input data available for simulation and allows its validation, residual stress measurements were conducted. The results of the numerical welding simulation are compared to experimental data to validate the model.