摘要 |
PURPOSE:To obtain continuously beautiful Uranami beads by making an alternating current flow to a magnetic field generating coil provided on a welding torch which can be placed in a prescribed direction, stirring magnetically a molten metal, and welding it. CONSTITUTION:A magnetic field generating coil 1 is provided on a welding torch 3. This torch 3 is placed in 8-11 o'clock and 1-4 o'clock, when a pipe to be welded 8 is rotated countelockwise, and when it is rotated clockwise, respectively, with respect to the peripheral direction of the pipe 8 placed horizontally on a rotary base. Subsequently, an alternating current is made to flow to said coil 1, a molten metal is stirred magnetically, and TIG welding, MIG welding or plasma welding is exectuted. |