Heating technology for avoiding surface defects of steel plate

Abstract

The invention relates to a heating technology for avoiding surface defects of a steel plate. The heating technology comprises the specific technological process that a continuous casting machine produces a plate blank, the plate blank is cut and sprayed with a number, the plate blank enters a heating furnace to be heated, primary rolling is conducted on the plate blank, finish rolling is conductedon the plate blank, coiling and packing are conducted, and a finished product is divided. Temperature control is conducted on the plate blank before the plate blank enters the heating furnace for heating, and the specific reaction condition comprises that the surface temperature of the plate blank is controlled to be higher than the Ar3 temperature or controlled to be lower than the Ar1 temperature and higher than 200 DEG C. By the adoption of the heating technology for avoiding the surface defects of the steel plate, on the premise of not increasing any equipment and production cost, hot delivery and hot charging of the plate blank are achieved, waste heat of a continuous casting blank is fully utilized, and then a good energy-saving effect is achieved; and oxidized scale on the surfaceof the steel plate is easier to remove, carbonitride is fully dissolved in the heating process, the high-temperature plasticity of steel is improved, and the surface defects such as slag inclusion andcracks of the rolled steel plate are avoided.

Description

Technical field [0001] The invention relates to a heating process for avoiding surface defects of steel plates, and belongs to the technical field of metallurgical continuous casting. Background technique [0002] The process flow of continuous casting slab rolling into steel plate is: slab produced by continuous casting machine → slab cutting and spraying → slab temperature control → slab heating in heating furnace → slab blooming → slab finishing rolling → coiling Bundling → finished product slitting (steel plate). [0003] Among them, the hot delivery and hot charging technology of the slab into the heating furnace is a major breakthrough in continuous casting technology. It not only saves energy and reduces consumption, but also has far-reaching significance for the reform of the traditional industrial structure. The economic benefit is greatly improved. However, at present, it is difficult to realize the hot delivery and hot charging technology of slabs, because many steel g...

AI Technical Summary

Problems solved by technology

However, it is very difficult to realize the technology of slab hot delivery and hot charging at present, because many steel types are relatively sensitive to the furnace temperature, and the temperature of the furnace is too high or too low to easily form the surface defects of the rolled material, so that It is difficult to control the surface quality and internal quality of hot coil

[0004] In addition, the heating process of the slab in the heating furnace has a profound impact on the uniformity of the hot coil product quality and mechanical properties. The slab heating process directly affects the microstructure and grain size of the final product. Improper heating and uniformity The heating temperature and the long heating and soaking time are the root causes of the large fluctuations in the performance of the final product

[0005] At present, most of the research on the control of steel plate surface crack defects is focused on smelting, ladle refining, hot rolling process, recrystallization, thermomechanical rolling, deformation compression optimization, cold rolling process, etc., but the surface temperature before loading the slab into the heating furnace Insufficient understanding and attention to control and control of heating furnace slab heating process

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