Numerical simulation of welding residual stress in Incoloy 825/L360QS bimetal clad tube

With severe corrosion issues afflicting nearly half of all high sulfur gas fields, bimetal composite tubes have emerged as an optimal solution due to their superior corrosion resistance, mechanical properties, and cost-effectiveness. These tubes have gained widespread adoption in gas gathering applications. However, the evaluation of the corrosion performance of Incoloy 825 bimetal composite tubes within high sulfur gas field environments is yet to be adequately addressed. An investigation into the welding performance of both the base metal and weld is instrumental in ascertaining the safety and reliability of bimetal composite pipes. To this end, this paper presents a thermodynamically coupled finite element model of bimetal composite pipes, developed using SYSWELD software, and corroborates the model using the borehole method for empirical verification. The study further delineates the distribution of residual stress encountered during multi-layer and multi-pass welding of bimetal composite pipes. •Welding simulation of bimetal tubes validates residual stress distribution.•Compressive stress dominates base metal; cap-shaped tensile stress is on the weld side.•High-stress near fusion line and transition layer risks cracking in bimetal pipes.•Numerical modeling and verification lead to safe application of bimetal composite pipes.