| 摘要 |
PURPOSE:To obtain stable penetration beads even during position welding while copying the groove by the arc per se in multilayer weaving welding by copying the groove by interrupting the arc control in a sub-section around the detecting central position of each weaving thereby changing welding current. CONSTITUTION:The position of a torch 2 in the groove width (X-axis) direction of base materials 1 for welding is detected with a meter 23, and is operated in a circuit 26 including analog memories 24, 25 which store right and left end positions Xl, Xr at every inversion of weaving. Said position is converted to the central position (Xl+Xr)/2 signal of every half period of weaving and is superposed with the position signal in the X-axis direction of each half period by a comparator 27. The position signal in the X-axis in every half period normalized by P'11 in the central position of the preceeding half period respectively before the previous one, for example, between the points D1-A2 is produced in the output of the circuit 27. Here, with the zero point P'11 as a center, peak current IP is flowed only in the specified sub-section DELTAX, and the control for arc length is interrupted. |
