| 摘要 |
PURPOSE:To prevent the defect in the weld zone of at a pipe end and to assure quality by welding the pipe while the spacing between a welding head and the pipe wall is kept in the state just before the suspension of copying a torch with a copying roll before the copying roll shifts to a tab plate. CONSTITUTION:A copying roll 5 supporting the entire load of a welding head 3 moves while copying the inside of the groove of a base material and the welding at the groove of the base material is progressed with a welding torch 4. Before the roll 5 moves to a tab plate 2, a limit 15 for detection operates and the distance up to each detection plate is detected with a distance detector in accordance with the signal thereof, then a motor 18 is started to move the body of a cylinder 16 for clamping a support roll up to the position of a prescribed distance between a guide 12 and a support roll 14. Thereafter, the head 3 is held in an optional state and is moved, and the roll 5 is deviated from the groove by a cylinder 11 for moving the copying roll vertically. The head 3 held by the roll 14 and a vertical support roll progresses welding and the welding is completed on the plate 2. |
