Electroslag welding method and electroslag welding apparatus

摘要

The present invention relate to an electroslag welding using a slide type backing plate capable of performing welding while maintaining a predetermined depth of a slag bath, and preventing mechanical features of welding metal by obtaining sound weld penetration. An electroslag welding device (100) comprises: a welding torch (4) having a contact tip (5) applying a current to a welding wire (6); a slide type copper backing plate (2); a driving carriage (16) including the welding torch (4) and the slide type copper backing plate (2); a molten slag bath detector (13); a flux supply device (14); a flux supply control device (15); and a driving carriage control device (17). The flux supply control device (15) controls a supply of flux in order for a length (Ld) of the welding wire (6) from a front end of the contact tip (5) to the molten slab bath (7) to be a predetermined length. The driving carriage control device (17) controls a driving speed of the driving carriage (16) such that a predetermined relation between a reference current value and a welding current (8) is satisfied. The welding is performed while a length (Ls) of the slag bath is maintained at a predetermined depth.