Multi-electrode electrogas arc welding method for thick steel plate and multi-electrode electrogas arc circumferential welding method for steel pipe

摘要

Multi-electrode electrogas arc welding method for thick steel plates and circumferential welding of steel pipes, which enables compatibility between welding efficiency improvement and welding defect reduction when butt-welding thick steel plates or steel pipes with a thickness of 40 to 300 mm in a vertical direction Method. An end portion of a thick steel plate to be welded is disposed opposite to form a groove, The route interval RO of the groove and the route surface RF satisfy a predetermined relationship, An electro-gas arc welding electrode is disposed on each of front and back sides of the groove, Welding was performed simultaneously from the lower side in the vertical direction to the upper side, Each electrogas arc welding electrode moves in synchronism with the level of the melt surface of the molten weld metal generated within the groove.