MAGNETIC BLOW DISCRIMINATION METHOD OF PULSE ARC WELDING

PROBLEM TO BE SOLVED: To quickly discriminate arc deflection by magnetic blow in pulse arc welding.SOLUTION: In the magnetic blow discrimination method of pulse arc welding which energizes the peak current during a peak period and the base current during a base period to generate an arc, photographs an arc generation part 3 by a CCD camera CM, and discriminates the generation of magnetic blow by processing photographed image data Cm, the center position of the arc is calculated not only by an image processing circuit GC from the image data Cm during the peak period, but also calculated from the image data Cm during the base period, wherein a displacement amount of center positions of both arcs is discriminated as a reference value or more and the generation of magnetic blow is discriminated to output a magnetic blow discrimination signal Ad. In this way, the arc deflection is directly discriminated from the image data, so that the generation of the magnetic blow can be quickly discriminated correctly even when the deflection status of the arc by the magnetic blow is small.