High-deposition low-heat-input plasma-twin-wire bypass arc welding device and method

Abstract

The invention discloses a high-deposition low-heat-input plasma-double-wire bypass electric arc welding device and method. The welding device comprises a plasma arc loop assembly, a double-consumable-electrode electric arc loop assembly and a coordination control unit. The plasma arc loop assembly comprises a plasma arc power supply, a conductive piece, a plasma annular electrode and a workpiece; the double-consumable-electrode arc loop assembly comprises an MIG / MAG power source, a composite welding gun, a bypass welding gun composed of a conductive fixing piece and a conductive nozzle, and a welding wire. During welding, the bypass welding wire electrode is used for replacing a workpiece molten pool electrode to serve as a cathode of an original MIG electric arc, that is, the bypass welding wire electrode and a welding wire anode of the original MIG electric arc form a double-consumable-electrode pair, a double-consumable-electrode electric arc arranged in a plasma arc is formed, and the high-deposition low-heat-input welding process is completed. Decoupling control between heating power input of a workpiece molten pool and metal deposition is achieved, so that heating power input of an MIG electric arc to a workpiece is reduced, the metal filling capacity of the MIG electric arc is enhanced, and the welding efficiency is improved.

Description

technical field [0001] The invention relates to a welding device and method in the technical field of material processing engineering, in particular to a plasma-twin wire bypass arc welding device and method with high deposition and low heat input. Background technique [0002] Plasma-MIG welding is a composite arc welding method. It is a composite welding process that combines plasma arc and inert gas shielded MIG arc. The strong arc stiffness is formed by compressing the plasma arc to ensure sufficient welding fusion. The key is that the plasma arc has the effect of "cathode atomization" to eliminate oxides, coupled with the MIG arc to ensure the supply of filler metal for the weld, especially suitable for the welding of medium and large thickness aluminum alloy sheets. [0003] MIG arc can be reverse-connected by DC, and has good cathode atomization effect when welding magnesium-aluminum and other alloys, which can effectively remove oxide film and improve the welding qua...

AI Technical Summary

Problems solved by technology

[0004] Due to the small welding deformation and high production efficiency, plasma-MIG welding is widely used, but the plasma-MIG composite arc uses the molten pool of the workpiece as the common electrode, that is, the plasma arc and the MIG arc work together on the same molten pool of the workpiece, but in the process of When welding aluminum alloy sheets with medium and large thickness, it is necessary not only to increase the plasma arc current to ensure the penetration of the molten pool, but also to increase the MIG arc current to ensure sufficient filler metal, thereby ensuring high deposition, which undoubtedly increases Increase the heat input to the molten pool of the workpiece, expand the heat-affected zone area of ​​the weld, and cause local deformation of the workpiece

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