Hot rolling method for improving surface quality of steel plate

Abstract

The invention relates to a hot rolling method for improving the surface quality of a steel plate. The hot rolling method comprises the following steps of slab continuous casting, heating furnace heating, first-time high-pressure water descaling, roughing rolling unit rolling (attached type vertical roll edge closing), head cutting flying shear head cutting and tail cutting, second-time high-pressure water descaling, seven-rack finishing rolling unit rolling, cooling treatment and coiling machine coiling, the vertical roll side pressure amount of vertical roll edge closing ranges from 15 mm to 35 mm, and cooling treatment adopts strip steel laminar cooling. Edge defects can be effectively reduced and even eliminated through vertical roll edge closing; the r value is increased, so that the formability of a strip steel is better; the roughness of a working roll of a F7 rack is improved, and the influence of grinding knife patterns on the surface of the strip steel is eliminated; working rollers from a F1 rack to a F4 rack are high-speed steel rollers, and rolling oil input is controlled, so that the surface quality of strip steel is improved, and the pressing-in defect of oxide scales is avoided; and rapid cooling can reduce the cooling difference between the edge and the core of the strip steel, and the uniformity of the structure and crystal grains of the strip steel is improved.

Description

technical field [0001] The invention relates to the technical field of hot rolling of steel plates, in particular to a hot rolling method for improving the surface quality of steel plates. Background technique [0002] Hot rolling is rolling above the recrystallization temperature. Hot rolling can improve the processing performance of metals and alloys, that is, the coarse grains in the cast state are broken, the cracks are significantly healed, the casting defects are reduced or eliminated, and the cast structure is transformed. In order to deform the structure and improve the processing performance of the alloy, at present, the development of hot rolling mainly focuses on the precise control of the plate shape, thickness accuracy, temperature and performance. With the rapid development of the automobile industry, users are demanding Higher requirements are put forward. Stripe defects after stamping are prone to appear in the finished strip steel after the existing hot-roll...

AI Technical Summary

Problems solved by technology

[0002] Hot rolling is rolling above the recrystallization temperature. Hot rolling can improve the processing performance of metals and alloys, that is, the coarse grains in the cast state are broken, the cracks are significantly healed, the casting defects are reduced or eliminated, and the cast structure is transformed. In order to deform the structure and improve the processing performance of the alloy, at present, the development of hot rolling mainly focuses on the precise control of the plate shape, thickness accuracy, temperature and performance. With the rapid development of the automobile industry, users are demanding Higher requirements are put forward, and the existing hot-rolled steel plate is prone to streak defects after stamping in the finished strip produced by the cold-rolling process

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