| 摘要 |
PURPOSE: To achieve the welding excellent in the quality for the narrow gap with small deposition, and to unnecessitate the manufacture of a welding torch of special structure. CONSTITUTION: In the TIG welding method in which a tungsten electrode 3 is inserted in a narrow gap 2a of works 1a, 1a, and the shield gas flows to achieve the arc welding, the double shield gas of the inner side shield gas 13 flowing from the periphery of the tungsten electrode 3 to its tip part and the outer side shield gas 14 having the stream toward the narrow gap 2a and the stream toward the outside is used. The tungsten electrode 3 can be projected from an energizing part 15 and an outer shield 12 by the length of 20 to 100mm. The inner side shield gas 13 prevents consumption of the long-projected tungsten electrode 3, and the outer side shield gas 14 prevents oxidation of the molten pool and also prevents inclusion of oxygen in the air. The sound welding is achieved thereby. |
