A self-shielded flux-cored wire for underwater wet welding

Abstract

The invention provides a self-protection flux-cored wire for underwater wet-method welding. The self-protection flux-cored wire is characterized in that a N6 nickel band is used as a metal covering of the wire, an alkaline calcium fluoride-aluminum oxide slag system is used as a flux-cored basic slag system, the internal flux core consists of calcium fluoride, aluminum powder, iron powder, magnesium oxide, silicon iron, lithium fluoride, manganese powder and metal chromium, and the weight percent of each component is as follows: 40 to 55 percent of calcium fluoride, 8 to 13 percent of aluminum powder, 5 to 9 percent of iron powder, 0.5 to 5 percent of magnesium oxide, 3 to 7 percent of silicon iron, 3 to 9 percent of lithium fluoride, 6 to 11 percent of manganese powder and 4 to 10 percent of metal chromium. When the flux-cored wire is used for the underwater wet-method welding, arc is likely to start, the electric arc is stable in combustion, the restarting arc is good in performance, the forming property of the weld seam is good, the tensile strength of the weld metal after being welded is not lower than 460MPa, and the underwater welding of the medium-low carbon steel and low-alloy high-strength steel structure of ordinary strength requirement can be satisfied.

Description

technical field [0001] The invention belongs to the technical field of welding materials, in particular to a self-shielding flux-cored welding wire for underwater wet welding with high tensile strength of deposited metal after welding. Background technique [0002] With the rapid development of the national economy and the urgent need of energy strategy, marine engineering began to continuously advance to the deep sea. As an important technology in ocean engineering and other fields, underwater welding is receiving more and more attention. From the installation and construction of offshore oil and gas platforms to the laying and maintenance of submarine pipelines, from sea salvage and rescue work to emergency repairs of large ships, underwater welding can be seen everywhere. Especially in recent years, with the continuous improvement of underwater welding technology, it has gradually become an indispensable escort technology in nuclear power, ports, bridges and other "wadin...

AI Technical Summary

Problems solved by technology

At present, most of the underwater wet welding materials developed at home and abroad are mainly underwater welding rods. Although the welding requirements of actual engineering structures can be met at present, when manual arc welding is used, frequent replacement of welding rods is required, and it is difficult to achieve continuous welding operations. , the work efficiency is very low, and it cannot meet people's development needs in the direction of high efficiency, high quality, and high automation.