| 摘要 |
PURPOSE:To reduce a welding defect, and to raise the work efficiency, by moving a torch along an intersection line of a base pipe and an oval column face inscribed to a branch pipe, when butt-welding the base pipe and the branch pipe in the shape of T. CONSTITUTION:When the end face of a branch pipe 2' of an outside diameter (d) is butted in the shape of T with the side face of a base pipe 1 of an outside diameter D and they are welded automatically, an oval pipe whose long axis is made equal to an inside diameter d' of the branch pipe 2' and whose short axis is made (d-2DELTAd) is supposed. An intersection line 15 formed by penetrating this oval pipe and the base pipe 1 is made a groove center line. Subsequently, the end part of the branch pipe 2' is cut along said intersection line 15, also the opening of the base pipe 1 is formed to a saddle shape, and a welding torch is moved along the intersection line 15. According to this method, a plane projection of the intersection line 15 is overlapped with an oval column face 16, and its elevated face projection becomes a smooth saddle shape E having no break point. Accordingly, a welding defect is reduced, and the work efficiency is raised. |
