Device and method for assisting gas metal arc welding by using externally applied magnetic fields

Abstract

The invention discloses a device and a method for assisting gas metal arc welding by using externally applied magnetic fields, belonging to the field of welding techniques under the action of magnetic fields. The device comprises necessary conventional equipment for gas metal arc welding, a short circuiting transfer detection circuit, an exciting drive circuit, a main exciting circuit and a magnetic head device. According to the invention, during droplet short circuit period, a transverse pulsed magnet field which is acted on a short circuit liquid bridge and perpendicular to a welding-wire axis can be generated so as to promote the advanced fracture of the short circuit liquid bridge; and compared with the conventional method, the method provided by the invention has the advantages that the peak current during the short circuit period is reduced, the induced explosion and splash are lowered, and the regularity of a short circuit cycle in the process of short circuiting transfer welding can be improved. The device disclosed by the invention is simple in manufacturing, and the welding process of short circuiting transfer is obviously improved.

Description

technical field [0001] The invention belongs to the technical field of magnetic field control welding, and in particular relates to a device and method for assisting gas-shielded metal welding with an external magnetic field. Background technique [0002] The short-circuit transition welding process is an important process method of gas metal shielded welding, which has the characteristics of low heat input, small deformation, suitable for all-position welding and easy to realize automation. However, the disadvantages of poor arc stability, poor weld formation and large spatter of the conventional short-circuit transition process of gas metal arc welding also hinder its wide application. The reason is that the droplet transfer is a random process during short-circuit transition welding, which causes the short-circuit time and arc burning time to fluctuate within a certain range. This fluctuation will cause instability in the welding process and cause differences in welding q...

AI Technical Summary

Problems solved by technology

In the STT method, the molten droplet realizes a spatter-free transition under the action of electromagnetic contraction force and surface tension, which has the advantages of small welding spatter, small smoke and regular weld shape, but its shortcomings are also obvious, mainly in the applicable current range Narrow, complex control, signal susceptible to interference

The CMT method combines the waveform control and the mechanical withdrawal of the welding wire. The whole welding process realizes the "heat-cold-heat" alternating cycle, which can be switched up to 70 times per second, and the welding heat input is greatly reduced. It is especially suitable for welding thin plates and ultra-thin. Non-sputter welding and brazing of thin plates, but the control of CMT is also quite complicated and the cost is high, which limits its promotion

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