| 摘要 |
PROBLEM TO BE SOLVED: To provide a MAG welding device capable of maintaining welding quality by suppressing occurrence of incomplete penetration, groove gouging, and spatter regardless of a type of a welding wire even in a narrow groove.SOLUTION: A MAG welding device 100 of the present invention welds a groove 3 formed between end surfaces of two steel pipes P facing each other in an axial direction. A groove angle of the groove 3 is 10-40°. A welding torch 1 for supplying a welding wire 11 toward the groove 3 while moving in a direction along a circumference of the steel pipe P and a welding power supply 2 for supplying welding current between the welding wire 11 and the steel pipe P are included. The welding torch 1 supplies a shield gas that is a mixed gas of Ar and COand in which a mixture ratio of COis 20-40% toward the groove 3. An inclination of an external characteristic of the welding power supply 2 is -17 to -10 V/100A. |
