PURPOSE: To provide a method for multi-pass automatic welding of thick plates where the horizontal position multi-pass butt welding of thick plates can be automated, and this welding can be efficiently executed to reduce the welding time.
CONSTITUTION: The horizontal position multi-pass butt welding is executed to the groove 22 formed by abutting the thick plates 12 in the vertical direction while individually detecting the welding position in the groove 22 by a plurality of welding torches 49A, 49B where the wire is led from the tip or by the individual sensor. In welding the respective pass, the welding is executed by the preceding welding torch 49A followed by the other welding torch 49B, where the diameter of the wire of the succeeding welding torch 49B is made smaller than that of the preceding welding torch 49A.
KUSANO KENICHIRO
WADA YOJI
FURUKAWA KATSUHIKO
