BUTT WELDING METHOD FOR ULTRA-THICK PLATE, AND BUTT WELDING EQUIPMENT FOR ULTRA-THICK PLATE

摘要

Provided is a butt welding method for an ultra-thick plate, for performing, on a groove, welding of a multilayer, of which each layer is formed by a single weld bead and which comprises a lower layer, a middle layer composed of a plurality of layers, and an upper layer. The step for forming the middle layer is provided with: a single layer forming step (S1) for forming a single weld bead in a groove; a cooling step (S2) for cooling the single weld bead to a predetermined temperature; and a reheating step (S3) after cooling for reheating the cooled welding bead. In addition, the butt welding method for an ultra-thick plate is provided with a laminating step (S4) for laminating weld beads of layers required for the welding of a multilayer by repeating, as many times as the number of the layers of the middle layer, a cycle comprising the single layer forming step, the cooling step, and the reheating step after cooling.