High-strength, high-toughness and seawater corrosion-resistant welding rod for ocean engineering

Abstract

The invention discloses a high-strength, high-toughness and seawater corrosion-resistant welding rod for ocean engineering. The deposited metal of the welding rod comprises the following ingredients in percentage by mass: not greater than 0.05 parts of C, not greater than 0.60 parts of Si, 1.30-1.80 parts of Mn, 0.25-0.40 parts of Cr, 2.20-2.80 parts of Ni, 0.35-0.55 parts of Mo, 0.15-0.40 parts of Cu, not greater than 0.006 parts of S, not greater than 0.010 parts of P, and not greater than 0.005 parts of Re. A preheating temperature can be lowered to 50 DEG C when 800MPa-grade high-strength steel for ocean engineering is welded by adopting the technology of the invention; the coating of the welding rod is high in moisture absorption, the welding toe is smooth, and all-position welding can be carried out; and the welding rod has a high welding joint metal strength (Rm of not less than 780MPa), a low diffusible hydrogen content, a low cold crack sensitivity, a high low-temperature impact strength Kv2 of more than 70J at minus 60 DEG C, extremely low S and P impurity contents, and excellent seawater corrosion resistance.

Description

technical field [0001] The invention relates to welding engineering, in particular to the application of a lifting system, a cantilever, a rack plate to a rack plate, and a semicircular plate to a semicircular plate in the leg of a semi-submersible offshore oil platform and a self-elevating drilling platform. It can also be used in the manufacturing fields of high-strength seawater corrosion-resistant equipment such as marine engineering ships, marine oil pipelines, and nuclear power plants of the same level of strength, and specifically relates to a high-strength, high-toughness seawater corrosion-resistant welding rod for marine engineering. Background technique [0002] Domestic iron and steel enterprises have made great breakthroughs in the research of large-thickness (100mm) TMCP high-performance steel such as petrochemical and marine engineering equipment. Welding consumables manufacturers have not yet broken through key technologies in the control of impurity elements ...

AI Technical Summary

Problems solved by technology

Tianjin Jinqiao Welding Material Group Co., Ltd. has developed J607RH, J707RH and J807RH welding rods with high strength and high toughness, with a diffusible hydrogen content of 3.65ml / 100g, but has not studied its corrosion resistance, low temperature toughness and application in marine engineering

[0005] Luoyang Ship Materials Research Institute has developed a matching ultra-low hydrogen high-toughness electrode for the hull steel 10CrSiNiCu, and conducted research on its conventional mechanical properties, crack resistance, and seawater corrosion resistance. The yield strength can reach about 470MPa , but it cannot be applied to the welding of higher strength grade steel

Wuhan Tiemao Welding Materials Co., Ltd. has developed the ultra-low hydrogen high toughness CJ807RH electrode, and analyzed its mechanical properties and welding process, but did not analyze whether it can adapt to the characteristics of the offshore platform steel structure

[0006] Although some domestic enterprises and scientific research institutes have developed different series of ultra-low hydrogen high-toughness electrodes, they have not conducted in-depth research on them, especially not combined with the actual use conditions of steel for deep-water offshore platforms. , ultra-low hydrogen, local mechanical performance evaluation of welded joints, high strength, high toughness, high purity and other aspects are comprehensively analyzed