| 摘要 |
PURPOSE:To eliminate a welding defect such as a blowhole, a lack of fusion, etc., and to obtain a fine crystal grain and a uniform structure by making a low frequency AC square wave current flow to an exciting coil which has been provided on a welding torch or a reinforcing plate, and executing the welding by stirring a molten metal. CONSTITUTION:The welding surface of a valve 1 which has been fixed to a copper reinforcing plate 12 and a clamp 15 is held so as to become horizontal. With respect to the valve 1 which is being rotated at a prescribed number of rotation, an alternating field is generated by an exciting coil 18 which has been provided on the tip of a TIG welding torch, and stirring of a buildup welding metal molten pool 2' is executed. In this regard, a welding material in case of the TIG welding is fed as a wire 3 into an arc 6 at a prescribed speed by feeding devices 4, 5. |
