Arc striking control method for double-electrode electric arc welding

Abstract

PROBLEM TO BE SOLVED: To optimize penetration and a bead shape of an arc start part in two-electrode arc welding. SOLUTION: In a method for controlling arc start for two-electrode arc welding performing arc welding using a welding torch WT equipped with a consumable electrode 1a and a non-consumable electrode 1b, a consumable electrode arc 3a is generated between the consumable electrode 1a and a base material 2. Then, the consumable electrode 1a is fed at a normal feeding speed, a non-consumable electrode arc 3b is generated between the non-consumable electrode 1b and the base material 2. Thereafter, during a preheating period, a preheating current having a larger value than a normal current value is made to flow to the non-consumable electrode arc 3b, a feeding speed is switched to a preheating feeding speed that is faster than the normal feeding speed in accordance with the preheating current value. Upon completion of the preheating period, the feeding speed is switched to the normal feeding speed and, simultaneously, the current value for energizing the non-consumable electrode arc 3b is switched to the normal current value and made to shift to the normal welding state. COPYRIGHT: (C)2010,JPO&INPIT

Description

technical field [0001] The invention relates to an arc starting control method for double-electrode arc welding. A welding torch (the welding torch has a melting electrode and a non-melting electrode, and these electrodes are arranged in a protective gas nozzle) is used to generate a melting electrode arc and a non-melting electrode arc. In arc welding, it transitions smoothly to a stable welding state and forms a good weld bead. Background technique [0002] Figure 4 An example of a two-electrode arc welding device is shown. In this figure, the melting electrode arc is a MIG (Metal Inert Gas) arc, and the non-melting electrode arc is a plasma arc. This welding apparatus includes a welding torch WT surrounded by a dotted line, a melting electrode arc welding power source (MIG arc welding power source) PSM, and a non-melting electrode arc welding power source (plasma arc welding power source) PSP. The welding torch WT has a structure in which a plasma nozzle 51 , a plasma ...

AI Technical Summary

Problems solved by technology

However, when the arc is started, the heat input to the base material is insufficient, so the penetration depth of the arc starting part is shallow, and the cross-sectional shape of the weld bead becomes convex.

When the cross-sectional shape of the weld bead becomes convex, the fusion of the edge of the weld bead will be poor, so the mechanical properties of the welded part will decrease

Furthermore, the appearance of the weld bead is not beautiful

In addition, since two-electrode arc welding has two pyrogens, it is mostly used at a relatively fast welding speed. In this high-speed welding, the above-mentioned problems are more significant.

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