Minimization of welding residual stress and distortion in large structures

Welding distortion in large structures is usually caused by buckling due to the residual stress. In cases where the design is fixed and minimum weld size requirements are in place, the thermal tensioning process has proven effective to reduce the welding residual stress below the critical level and eliminate buckling distortion. In this work, a systematic design approach using conventional finite element analysis, analytic sensitivity analysis and nonlinear programming is implemented to investigate and optimize the thermal tensioning process.