| 摘要 |
PURPOSE:To assure the quality of a weld zone and to obtain satisfactory appearance of beads by forming the central part on the end faces of base materials into a specific flat state prior to welding, chamfering both side edges of the end faces and welding the base materials. CONSTITUTION:A web material 1 is cut to a prescribed width and chamfered parts 3 are formed at both side edges on both end faces of the material 1 by means of grooved rollers 2 in the 2nd stage in the case of manufacturing an H- beam. The material 1 formed with the chamfered parts 3 is preupset by preupsetting rollers 4 in the 3rd stage. The material 1 and base materials 5 are thereafter subjected to high-frequency resistance welding. The central part on the end face of each base material is formed flat to >=50% of the thickness of the base material. |
