Method for smelting bearing steel through SHARC electric arc furnace

Abstract

The invention relates to a method for smelting bearing steel through an SHARC electric arc furnace, and belongs to the technical field of metallurgy control methods. According to the technical scheme, the method comprises the steps that (1) smelting models are established and optimized, and corresponding smelting models are established and optimized according to different kinds of carbon-containing waste steel; (2) a slagging system is optimized, and slagging is conducted through different proportions of slagging materials; and (3) performing proportioning flow and mode use setting of the carbon lance and the oxygen lance. The method has the beneficial effects that the efficient foam slag is kept, the carbon powder utilization rate and the spraying amount are guaranteed, the power-on time is shortened, and the smelting speed is increased.

Description

Technical Field

[0001] The invention relates to a method for smelting bearing steel in a SHARC electric arc furnace, belonging to the technical field of metallurgical control methods. Background Art

[0002] Currently, the world's mainstream steelmaking methods are divided into converter steelmaking and electric furnace steelmaking. Judging by production capacity distribution, my country currently relies primarily on the long-process steelmaking model, primarily based on blast furnaces and converters. China's electric arc furnace production capacity is 191.21 million tons, while converter crude steel production capacity is 987.89 million tons, representing less than 20% of the short-process steelmaking capacity. Compared to our long-process steelmaking model, electric furnaces have a relatively recent history in my country, having begun in 1993. Following the "Contemporary Electric Furnace Process and Electric Furnace Engineering Issues Seminar" held in Shanghai by the former Ministry of Metallurgy and the Shanghai Municipal Government to discuss electric furnace steelmaking technology, a number of steel companies, including Baosteel, Xinjiang Bayi Steel Plant, Shaoguan Iron and Steel, and Laiwu Iron and Steel, imported electric furnace steelmaking production lines from abroad, enabling the development of electric furnace steel in my country.

[0003] Long-process steelmaking relies primarily on coal for its energy structure. The steel industry accounts for 16% of China's total energy consumption, of which coal accounts for 70% and is the primary source of carbon emissions. Long-process steelmaking emits 2.34 tons of CO2 per ton of steel, of which pre-iron production accounts for over 80%. However, electric furnace steelmaking, which uses scrap steel as raw material, emits 0.67 tons of CO2 per ton. Therefore, increasing scrap recycling and reducing the iron-to-steel ratio can significantly reduce CO2 emissions. my country's steel industry is entering a critical juncture of structural adjustment, transformation, and upgrading. Amidst the current severe environmental situation, the electric furnace short process, with its lower pollution emissions, has broad prospects for development, driving a higher share of electric furnace steel production. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for smelting bearing steel in a SHARC electric arc furnace. By optimizing the main blowing, protective gas and fluidizing gas of the carbon gun system, adjusting the structure of the slag entering the furnace, and establishing optimized corresponding smelting models for different carbon-containing scrap steels, the maintenance of efficient foamed slag is achieved, the utilization rate and injection amount of carbon powder are guaranteed, the power-on time is reduced, the smelting speed is accelerated, and the above-mentioned problems existing in the background technology are effectively solved.

[0005] The technical solution of the present invention is: a method for smelting bearing steel in a SHARC electric arc furnace, comprising the following steps: (1) Establish and optimize the smelting model, and establish the corresponding optimized smelting model for different carbon-containing scrap steel; (2) Optimize the slag making system and make slag by using different proportions of slag making materials; (3) Set the ratio flow rate and mode of use of the carbon gun and oxygen gun.

[0006] In the step (1), six oxygen-burning guns evenly distributed on site are matched with different currents, voltages and carbon injection amounts to melt and heat the scrap steel at the fastest speed to meet the steel tapping requirements.

[0007] In the step (2), slag formation is performed by improving the amount of added lime, dolomite, magnesium balls and carbon balls.

[0008] In step (3), the carbon gun flow rate, carbon gun protection and carbon gun material are optimized, and the maximum carbon gun flow rate reaches 60m 3 / min, the carbon gun system is protected by asbestos rope, and the internal material of the carbon gun is improved from steel pipe to ceramic.

[0009] In step (3), the peak flow rate of the oxygen gun reaches 2600m 3 / min, and at the same time improve the fuel-oxygen ratio, and start different modes according to the changes in power-on time.

[0010] The beneficial effects of the present invention are: by optimizing the main blowing gas, protective gas and fluidizing gas of the carbon gun system, adjusting the structure of the slag material entering the furnace, and establishing an optimized corresponding smelting model for different carbon-containing scrap steels, efficient foam slag maintenance is achieved, the carbon powder utilization rate and injection amount are guaranteed, the power-on time is reduced, and the smelting speed is accelerated. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solutions and advantages of the invention implementation cases clearer, the technical solutions of the present invention will be clearly and completely described in combination with the implementation cases below. Obviously, the implementation cases described are only a small part of the implementation cases of the present invention, rather than all the implementation cases. Based on the implementation cases in the present invention, all other implementation cases obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0012] A method for smelting bearing steel using a SHARC electric arc furnace comprises the following steps: (1) Establish and optimize the smelting model, and establish the corresponding optimized smelting model for different carbon-containing scrap steel; (2) Optimize the slag making system and make slag by using different proportions of slag making materials; (3) Set the ratio flow rate and mode of use of the carbon gun and oxygen gun.

[0013] In the step (1), six oxygen-burning guns evenly distributed on site are matched with different currents, voltages and carbon injection amounts to melt and heat the scrap steel at the fastest speed to meet the steel tapping requirements.

[0014] In the step (2), slag formation is performed by improving the amount of added lime, dolomite, magnesium balls and carbon balls.

[0015] In step (3), the carbon gun flow rate, carbon gun protection and carbon gun material are optimized, and the maximum carbon gun flow rate reaches 60m 3 / min, the carbon gun system is protected by asbestos rope, and the internal material of the carbon gun is improved from steel pipe to ceramic.

[0016] In step (3), the peak flow rate of the oxygen gun reaches 2600m 3 / min, and at the same time improve the fuel-oxygen ratio, and start different modes according to the changes in power-on time. Example

[0017] The production process of bearing steel GCr15 includes smelting model, slag making system, carbon gun, oxygen gun matching, etc. (1) Smelting model: Bearing steel scrap melting and oxygen control operation model.

[0018] (2) Slag making system: through different proportions of slag making materials (lime, iron balls, magnesium balls, dolomite) and the use of carbon powder sprayed in electric furnaces.

[0019] (3) Carbon gun and oxygen gun combination: the maximum flow rate of the carbon gun can reach 60m 3 / min, the peak flow rate of the oxygen gun reaches 2600m 3 / min, while improving the fuel-oxygen ratio and opening different modes according to the changes in power-on time.

[0020] After establishing the optimization model, the cycle of smelting bearing steel was reduced from one hour to 54 minutes.

[0021] The beneficial effects of the present invention are: (1) The present invention establishes an automatic smelting model for the SHARC electric furnace, providing strong support for standardized steelmaking.

[0022] (2) The present invention optimizes equipment protection and the ratio of the oxygen-fired gun, and further updates the equipment use and optimization.

[0023] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for smelting bearing steel in a SHARC electric arc furnace, characterized in that The following steps are involved: (1) Establish and optimize the smelting model, and establish the corresponding optimized smelting model for different carbon-containing scrap steel; (2) Optimize the slag making system and make slag by using different proportions of slag making materials; (3) Set the ratio flow rate and mode of use of the carbon gun and oxygen gun.

2. The method for smelting bearing steel using a SHARC electric arc furnace according to claim 1, wherein: In the step (1), six oxygen-burning guns evenly distributed on site are matched with different currents, voltages and carbon injection amounts to melt and heat the scrap steel at the fastest speed to meet the steel tapping requirements.

3. The method for smelting bearing steel using a SHARC electric arc furnace according to claim 1, wherein: In the step (2), slag formation is performed by improving the amount of added lime, dolomite, magnesium balls and carbon balls.

4. The method for smelting bearing steel using a SHARC electric arc furnace according to claim 1, wherein: In step (3), the carbon gun flow rate, carbon gun protection and carbon gun material are optimized, and the maximum carbon gun flow rate reaches 60m 3 / min, the carbon gun system is protected by asbestos rope, and the internal material of the carbon gun is improved from steel pipe to ceramic.

5. The method for smelting bearing steel using a SHARC electric arc furnace according to claim 1, wherein: In step (3), the peak flow rate of the oxygen gun reaches 2600m 3 / min, and at the same time improve the fuel-oxygen ratio, and start different modes according to the changes in power-on time.