| 摘要 |
PROBLEM TO BE SOLVED: To provide a welding method that excels in arc stability even in the initial layer (i.e., bottom of a groove) of multi-layer welding and that enables stable penetration to be obtained, in performing narrow groove butt welding for a thick steel plate by a gas shielded arc welding method. SOLUTION: In the narrow groove butt welding method in which multi-layer gas shielded arc welding is performed on a thick steel plate using a welding steel wire composed of a steel wire containing 0.015-0.100 mass% rare earth elements; the gas shielded arc welding of the initial layer is performed under the conditions that a QL value determined by QL=I×E/[S×(G+5×tanθ)]/60 satisfies in the range of 1.5-10.0 and that a QH value determined by QH=[G×S×60×(G+tanθ)/(I×E)]+tanθsatisfies in the range≥1.0. COPYRIGHT: (C)2007,JPO&INPIT |
