Production method of HRB600E high-strength anti-seismic reinforcing steel bar

Abstract

The invention provides a production method of an HRB600E high-strength anti-seismic reinforcing steel bar, and relates to the technical field of reinforcing steel bar production. The method includes the following steps: melting in a blast furnace, charging in a converter, refining in an LF furnace, continuously casting and cooling and rolling to obtain a finished product; a process route of blast furnace molten iron, a converter, an LF (ladle furnace), high-pulling-speed continuous casting and a rolling mill is adopted, a converter smelting process, a microalloying process, an LF refining inclusion removal process, continuous casting electromagnetic stirring, an automatic water distribution process, hot rolling processes such as optimization of hot rolling starting temperature and controlled cooling after rolling are adopted, and a through-water cooling process is not adopted; and the high-strength anti-seismic reinforcing steel bar is produced through converter smelting and by adopting a niobium and vanadium nitrogen microalloying process, the method is similar to a common deformed steel bar smelting process, operating is easy, applicability is high, popularization is convenient, ferroniobium and vanadium nitrogen alloy is added in the tapping process, the alloy yield is high, molten steel components can be accurately controlled, and the product performance is stably controlled.

Description

technical field [0001] The invention relates to the technical field of steel bar production, in particular to a production method of HRB600E high-strength earthquake-resistant steel bar. Background technique [0002] Steel bars for construction are the varieties with the largest output and consumption in China, accounting for about 1 / 4 of the entire steel output. As my country's economy shifts from high-speed development to high-quality development, higher requirements are placed on the performance of steel bars for construction. Under the current background of energy saving, emission reduction, low-carbon and environmental protection, HRB600E high-strength steel bar not only conforms to the trend of upgrading steel bars for construction, promotes the development of high-quality steel, but also meets the requirements of earthquake resistance, significantly improving the safety of building structures, and can be widely used Used in key projects and high-rise buildings. It invo...

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Problems solved by technology

[0003] In the prior art, in the process of HRB600 described in "HRB600 high-strength anti-seismic rebar and its production method" (CN111500920A), the component carbon: 0.22-0.33%, cannot meet GB / T1499.2 "Hot-rolled ribbed steel bars" Standard requirements; composition niobium: 0.015-0.13%; copper: 0.05-0.10%, which is difficult to adapt to the continuous casting high-speed casting process; and the rolled rebar is subjected to online waste heat treatment through three-stage cooling water pipes, and the temperature of the finished product on the cooling bed It is 575~620 ℃, and the tempering structure of the product metallography is easy to appear; In the process of HRB600E described in "HRB600E vanadium-titanium microalloyed high-strength shock-resistant hot-rolled steel bar" (CN111172459A), the composition vanadium+titanium: 0.10~0.25%, titanium is It is very easy to oxidize alloy elements, and its alloy content is difficult to control stably; and after rolling, the steel bar is cooled to 800-950°C on the cooling bed, and the metallographic structure of the product is prone to tempering structure; "A HRB600E high-strength earthquake-resistant steel bar and its production method" ( In the process of HRB600E described in CN108913995A), the rolled piece is also subjected to water cooling and recovery, the surface cooling rate of the rolled piece after water cooling is less than 33°C / s, and the surface temperature of the rolled piece after water cooling is not lower than 650°C. The maximum recovery temperature of the steel bar is 850-1050°C, and finally it is naturally cooled to room temperature, and the metallographic structure of the product is prone to tempering structure;

[0004] In the above three processes, the products are all passed through the water cooling process after rolling. According to the GB / T1499.2 "Hot Rolled Ribbed Steel Bar" standard and the clear regulations issued by the national construction steel production license, the water cooling process is not allowed In addition, titanium or niobium alloy elements are used for strengthening. Titanium alloys are easily oxidized, and the alloy content is not easy to control stably. The content of niobium alloy elements is high, and the continuous casting process is difficult to control, especially not suitable for high-speed continuous casting. The production process is not suitable for general promotion in steel mills. Therefore, the present invention proposes a production method of HRB600E high-strength anti-seismic steel bars to solve the problems existing in the prior art

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