NON-COMSUMABLE NOZZLE TYPE ELECTROSLAG WELDING METHOD

PROBLEM TO BE SOLVED: To perform a non-comsumable nozzle type electroslag welding producing an excellent internal quality by re-welding with another equipment having a straight feeding nozzle stationarily arranged on a upper flange before the slag bath is completely solidified. SOLUTION: A feeding nozzle 6 is drawn up by driving a carriage 4, an opposing upward welding is performed and another stationary water-cooling copper plate for the front side is installed on the upper end of a stationary water-cooling copper plate 9 for the front side after a molten slag bath passes through the center part in the longitudinal direction of the stationary water- cooling copper plate 9 for the front side. After that, the same process is repeated for a long size welding. When welding can not be continued owing to interference between the feeding nozzle 6 and the upper flange 1, the feeding nozzle 6 is removed from a web groove, a feeding nozzle 7 of a stationary welding equipment 5 provided on the upper flange 1 is lowered to start re-welding. When the molten slag bath comes near the rear side of the upper flange 1 according to the advance in welding, a copper tab 12 for the end is set. When the upper face of the molten slag bath comes to approximately the upper face of the copper tab 12 for the end, welding is terminated.