| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a welding control means allowing a heat input amount not to fluctuate even when a groove sectional area fluctuates when manufacturing a welding joint formed of a steel plate with a plate thickness of >50 mm without using a specified expensive instrument. <P>SOLUTION: When welding is carried out at a constant voltage by moving upward a truck mounted with a welding torch along a groove of a steel plate and two electrode vertical electrogas arc welding is carried out by controlling the truck to move upward following ascending speed of a melt pool based on a welding current, the welding torch is mounted on the truck so as to be moved, the moving speed of the truck is measured, and difference between the moving speed and reference welding speed preliminarily set is calculated for each constant interval. When there is difference, the welding torch is moved upward or downward with a constant distance to change the length of the protrusion of the welding wire, wire feeding speed is changed corresponding to the change of the welding current to control the welding current so as to become constant, and the ascending speed of the melt pool is made to coincide with the reference welding speed to allow heat input during welding to be constant so that welding is carried out. <P>COPYRIGHT: (C)2012,JPO&INPIT |
