Multi-welding-wire gas-shielded welding process capable of replacing stainless steel band-electrode surfacing

Abstract

The invention relates to a multi-welding-wire gas-shielded welding process capable of replacing stainless steel band-electrode surfacing. The process comprises the following steps: step 1, using 309LMo stainless steel welding wires to respectively twist stranded welding wires with a phi6.0mm 1*19 stranded structure in left-lay and right-lay directions; step 2: taking a German EMW double-wire welder, placing the stranded welding wire in the left-lay direction in step 1 on the left side of the double-wire welder, placing the stranded welding wire in the right-lay direction in step 1 on the rightside of the double-wire welder, and performing double-wire double-arc common-molten-pool gas shielded welding, wherein welding current is 500A, voltage is 31.5V, and shielding gas is pure CO2. The invention provides the multi-welding-wire gas-shielded welding process capable of replacing the stainless steel band-electrode surfacing, which does not need an expensive sintered flux matched, and is beneficial to eliminating the defects such as uneven welding layer thickness, welding layer edge undercuts and weld toe residue, caused by instable welding current and voltage in a band-electrode submerged arc surfacing process.

Description

technical field [0001] The invention relates to a multi-strand welding wire gas-shielded welding process which can replace the surfacing welding of stainless steel strips, and belongs to the field of welding technology. Background technique [0002] In recent years, with the development of the petrochemical industry, high-temperature, high-pressure, and corrosion-resistant pressure vessels tend to be large-scale and large-scale, such as thick-walled pressure vessels such as hydrogenation reactors, raw flow synthesis towers, and coal liquefaction reactors. In the manufacture of such thick-walled pressure vessels, in order to reduce costs, the common manufacturing method is to use low-alloy steel forging or thick plate coiling to make the cylinder and head, and then surfacing stainless steel lining on the inner surface to achieve corrosion resistance. High temperature and high pressure design requirements. [0003] For large area surfacing, manual arc welding and wire surfaci...

AI Technical Summary

Problems solved by technology

[0011] The technical problem to be solved by the present invention is to provide a multi-strand welding wire gas shielded welding process that can replace stainless steel strip surfacing, which does not need to match expensive sintering flux, and is conducive to eliminating the strip submerged arc surfacing process. There are defects such as uneven welding layer thickness, undercut at the edge of the welding layer and welding toe residues due to unstable welding current and voltage.