Prevention of solidification cracking during tandem-submerged are welding of longer plates

The advantage of high deposition efficiency of tandem-submerged are welding process costs short solidification cracking at the end of longer butt weld seams in the prefabrication of shipbuilding. The displacements, stresses and strains during the welding process of longer plates are calculated along the seam with the help of finite element modelling. The results show a strong increase in the cross displacement at the seam end, where the solidification cracks occur. A special hot cracking criterion is based on the equilibrium between structural and metallurgical effects during the welding process. It uses the velocity of the cross displacement to derive methods for the prevention of solidification cracking. A special heat device was developed to heat up the external edges simultaneously to the welding process with the required heating dose. Their effects on one-side submerged are welding are described, and the calculated and experimental results are compared.