AREVA has developed narrow gap weld techniques to perform junctions between low alloy steel heavy section components and austenitic stainless steel piping systems. In parallel, for a good understanding of welding and post weld heat treatment consequences, numerical welding simulation has already demonstrated its relevance to predict residual stress fields in welded components .
This paper presents Finite Element (FE) simulations of a 29″ multipass narrow gap Dissimilar Metal Weld (DMW) configuration, the welding simulation including non linear kinematic hardening models, phase transformations and visco-plastic calculations for reproducing the post weld heat treatment.
The numerical results are compared to measurements obtained by the deep hole drilling technique . This work gives another evidence of the relevance of the numerical welding simulation. Particularly, the comparison with a 14″ configuration  gives some elements to assess on the validity of both numerical and experimental techniques and on the weld thickness effect.