Henry Granjon Prize Competition 2005 “Design and structural integrity” Localized Thermal Tensioning Technique to Prevent Buckling Distortion

Abstract

An in process distortion mitigation method, localized thermal tensioning technique, also named DC-LSND welding technique, has been developed by introducing a trailing heat sink during conventional GTAW. The thermal elasto-plastic finite element analysis procedure was developed to quantitatively study the effect of heat sink on the thermomechanical process during welding and to find out the stress and distortion controlling mechanism of the proposed technique. Welding trials were also conducted to verify the effectiveness of the technique and the validity of the finite element model. Finally, effects on controlling results of process parameters were studied for heat sink; i.e., the distance between heat sink and welding arc (d) and cooling intensity of heat sink (h). Based on these studies, the methods to determine optimal heat sink parameters are presented for engineering applications.