Deformations and Stresses in Butt-Welding of Large Plates With Special Reference to the Mechanical Material Properties

Simulation of automatic butt-welding of large plates was investigated. Two different steels were considered. The plates were tack-welded before the butt-welding. The simulation includes the tack-welding, the butt-welding and the cooling to room temperature. The simulations should lead to an understanding of the mechanics behind the change in gap width in front of the moving arc, which is of importance in automatic welding production. The residual stresses due to the butt-welding were also studied. The magnitude and the distribution of the residual stresses are important in design of welded structures. The change in gap width in front of the moving arc and the residual stresses depend on the material in the plates, the restraints of the plates, the size of the plates and the welding parameters. The most important welding parameters are the arc energy per unit length of the weld and the welding speed. The change in gap width depends also on the tack-welding procedure.