METHOD FOR AUTOMATICALLY CONTROLLING WELDING IN INITIAL LAYER PENETRATION WELDING OF MULTILAYER FILL ARC WELDING

摘要

PROBLEM TO BE SOLVED: To provide a method for automatically controlling welding in all attitude in an initial layer penetration welding of a multilayer fill arc welding which can suppress a change in a gap between a groove width and a backing metal in all attitude, further lack of fusion, in sufficient penetration and the like of a welding bead caused by a change or the like of an oscillation width, a welding quantity, etc.;SOLUTION: The method for automatically controlling welding in the initial layer penetration welding of the multilayer fill arc welding comprises the steps of: image processing the groove width direction of the molten pool image imaged from obliquely forward with respect to a welding advancing direction as an X-axis coordinate axis and the welding advancing direction as a Y-axis coordinate axis; deciding whether the molten pool front edge shape is an arch-state or an oblique shape according to the relation between the Y-axis coordinate value of left side lowermost end point and right side lowermost end point of the molten pool image measured by the image processing and the Y-axis coordinate value of the lower end point on the centerline of the pond image, increasing the welding speed of the welding torch in response to the decision, and controlling any of decreasing the oscillation width or reducing the welding speed.;COPYRIGHT: (C)2004,JPO