| 摘要 |
PURPOSE:To prevent the formation of discolored oxidzed films during welding in welding a bottom plate and side plates and forming a box-shaped vessel by ejecting an inert gas to the inside surface of welding parts as well. CONSTITUTION:In providing side plates 2 on the respective sides of a bottom plate 1, erecting the plates 2 to a box shape, and welding the side edges (a) of the adjacent plates 2, these are grasped and fixed by means of inside and outside jigs 3, 3', and an inert gas is ejected from a welding electrode 4, whereby TIG welding is executed. In the prior art, the ejected inert gas does not arrive at the inside surface of the weld zones and therefore the inert gas is ejected simultaneously with welding by branching the gas supply pipe to the electrode 4 on the way, installing a piping to the jig 3 and previding an ejection part thereto. Quality is markedly improved by this. |
