A method for producing sulfur-containing gear steel for wind power gears

Abstract

The invention discloses a method for producing sulphur-containing gear steel for a wind power gear. The method comprises the following steps that end-point carbon and oxygen equilibrium is 0.0026% orbelow during melting in a converter, and FeO content in large ladle slags is 1.5wt% or below; LF refining final slags adopt a high basicity and low Ca-Al ratio, RH adopts high vacuum and large circulation operation, after calcium treatment, sulphur wires are fed at interval time of greater than or equal to 8 minutes, and the soft blowing time is greater than or equal to 10 minutes; in the whole process of continuous casting, protective casting is achieved, and dynamic soft reduction is adopted; the drawing speed is stably controlled within the standard drawing speed range of 0.6+ / -0.025 m / minand the water content of secondary cooling ratio is controlled at 0.45-0.50; after continuous casting, a rectangular billet is subjected to heating and cogging, and then is rolled into the square billet and slowly cooled; after checking the slowly-cooled square billet, four horizontal surfaces are coated with anti-high-temperature and anti-oxidation coatings; and the square billet is heated in a heating furnace, the surface of the square billet is dephosphorized by high pressure water after being heated, then a finished bar is rolled according to the conventional process, and the temperature is controlled at 800-830 DEG C after finishing rolling. By means of the method for producing sulphur-containing gear steel for the wind power gear, the technical problems of high oxygen content, unstable composition content and uniformity, uncontrollable sulfide precipitation and high banded structure grade can be effectively solved.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and in particular relates to a method for producing sulfur-containing gear steel for wind power gears. Background technique [0002] As a clean and renewable energy, wind power plays an increasingly obvious role in supporting the national economy. Generally speaking, wind power generation equipment is mostly installed in extreme conditions such as seaside and desert and supported on 100-meter-high working towers. The harsh service environment and high installation and maintenance costs it endures are unmatched by conventional industrial equipment. [0003] Wind power gear is the most important and also the most fragile part of the transmission shaft system of traditional wind turbines. Once an internal fault occurs in the wind power gear box, it is basically impossible to deal with it in the nacelle, and it is necessary to use hundreds of tons of cranes for product replacement. At the same tim...

AI Technical Summary

Problems solved by technology

[0007] In summary, due to the difficulty in controlling the production process of sulfur-containing gear steel for wind power, the sulfur-containing gear steel produced in the prior art still has high oxygen content, unstable composition content and uniformity, and difficulty in controlling sulfide precipitation. , high-level technical issues such as banded organization

[0008] The Chinese patent with the publication number CN102703817A discloses "a kind of free-cutting gear steel and its production process". The standardization of the timing of adding calcium wire and sulfur wire for stability is not involved; the Chinese patent with publication number CN102011062B discloses "a free-cutting gear steel and its smelting method", and introduces the addition of sulfur-containing alloys through a vacuum degassing process to improve the product Machinability, but for the adjustment of cooling rate in the continuous casting process, the beneficial effects of double heating on the sulphide precipitation and shape control in the billet opening and rolling process are not mentioned

Images