| 摘要 |
PURPOSE:To reduce streaky defects generated in forge welding zone in a method that manufactures a forge welded tube by butting both edge parts and forge welding, by butting and forge welding while applying axial stress on both side edge parts. CONSTITUTION:A skelp is passed through a heating furnace, and both side edge parts are heated to forge welding temperature. It arrives at a forming roll 2 from a roller 15 in a state that distance of moving differs between the central part of the skelp and edge parts on both sides, and stronger axial tension is applied to the both edge parts than the central part. Further, axial stress is controlled by adjusting the height of the roll 15. Accordingly, in moving to the forming roll through the roll 15, the skelp arrives at a forge welding roll while being given circumferential stress and axial stress to the both side edge parts, and both edge parts are butted and forge welded. |
