Novel self-shielded flux-cored wire for submerged arc welding

Abstract

The invention provides a novel self-shielded flux-cored wire for submerged arc welding. The self- shielded flux-cored wire is characterized in that liquid slag completely covers electric arcs, moltendrops and molten pools in the welding process, and the self-shielded flux-cored wire comprises a metal sheath and a flux core, wherein the metal sheath is an N6 nickel strip, and the neutral fluoride-rutile slag system is taken as a basic slag system of the flux core. The formula of the flux core comprises the following components of, in mass percent, 10%-35% of rutile, 20%-40% of fluoride, 10%-20% of manganese powder, 3%-10% of aluminum powder, 5%-15% of molybdenum powder, 0%-5% of chromium powder and balance iron powder. According to the flux-cored wire, electric arc combustion is stable inthe welding process, the phenomenon of arc breaking is avoided, the spatter rate is low, the forming performance of welding seams is good, the tensile strength of welded joints is up to 550 Mpa, the diffusible hydrogen content of the joints is lower than 5 ml / 100 g, and the standard of ultra-low hydrogen welding materials is reached.

Description

technical field [0001] The invention belongs to the technical field of welding materials, and in particular relates to a novel self-shielding flux-cored welding wire similar to submerged arc welding. Background technique [0002] Underwater welding technology is one of the key technologies for developing the ocean, exploiting seabed oil, and assembling and repairing large-scale ocean structures such as oil drilling platforms, oil pipelines, and submarine warehouses. It is also necessary for ship emergency repairs, sea rescue, and bridge erection. Technical means have also been widely used in nuclear power, ports, bridges and other industries in recent years. Underwater wet welding has the advantages of simple equipment, low cost, flexible operation and strong applicability, which can meet the application of underwater welding engineering. Self-shielded flux-cored wire has the advantages of automatic welding, which makes it easier to be applied in underwater welding construc...

AI Technical Summary

Problems solved by technology

Acidic slag-based welding wire has a stable welding process and good shape, but it has a low degree of suppression of diffusible hydrogen, and the slag has a high melting point and high density, so it is not suitable to cover the welding area

The welding process stability of alkaline slag-based welding wire is worse than that of acidic slag-based welding wire. Although it can reduce the diffused hydrogen content of the joint, it cannot guarantee good forming quality, and the melting point of slag is low, the density is small, and the liquid slag is easy to fly out. Cover the welding area

In addition, the current welding wires on the market can only be applied in a single welding environment in the air environment or water environment, and cannot complete the multi-purpose effect of welding underwater and in the air

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