Method for controlling cold buckling of ultra-deep-drawing wide plate

Abstract

The invention discloses a method for controlling cold buckling of an ultra-deep-drawing wide plate, which comprises the following steps of: controlling six CQ-grade steel coils of which the width is greater than that of a target coil according to the annealing temperature and the annealing speed of the target coil, so that the roller shape and the temperature of a furnace roller are stable; two DQ-level steel coils with the width larger than that of a target coil are used, control is conducted according to the tension of the target coil, and the overall tension state is in a stable state; the temperatures of the CQ grade, the DQ grade and the target steel coil are set as follows: the temperature of an outlet of a slow cooling section is 630 DEG C, the temperature of an outlet of a rapid cooling section is 370 DEG C, and the aging section is naturally cooled; the CQ grade, the DQ grade and the target steel coil cooling speed are set as follows: the cooling speed of a slow cooling section is 11 DEG C/S, the cooling speed of a rapid cooling section is 28 DEG C/S, and natural cooling is performed in an aging section; speed setting: setting according to the length of each cooling section of different annealing furnaces; the tension is set as follows: the heating section is 4.5 KN, the slow cooling section is 6 KN, the rapid cooling section is 7 KN, and the aging section is 5.5 KN.

Description

technical field [0001] The invention belongs to the technical field of cold rolling, and in particular relates to a method for controlling the cold buckling of an ultra-deep-drawing wide-width plate. Background technique [0002] In the production of continuous super deep drawing wide sheet, the steel coil is heated to 850 degrees in the heating section, cooled to 660 degrees after entering the slow cooling, and then cooled to 370 degrees in the fast cooling and aging sections. In the process, the strip is rapidly cooled down. Due to the temperature difference between the furnace roll and the surface of the strip, the convexity of the furnace roll, and the uniformity of the bellows cooling, the strip stress will be released unevenly, resulting in the formation of strip ribs. The figure-eight-shaped cold scoop has a slight twill defect after the skin-pass mill rolling, which cannot meet the needs of customers. In severe cases, the scoop will directly cause the strip to deviat...

AI Technical Summary

Problems solved by technology

[0002] During the production of continuous annealing ultra-deep drawing wide-width plates, the steel coil is heated to 850 degrees in the heating section, cooled to 660 degrees after entering slow cooling, and cooled to 370 degrees in the fast cooling and aging sections. In the process, the strip steel is cooled rapidly. Due to the temperature difference between the furnace roll and the strip steel surface, the certain convexity of the furnace roll, and the uniformity of the bellows cooling, the stress release of the strip steel will be uneven, resulting in the formation of ribs on the strip steel. Eight-shaped cold warp, after rolling by the temper mill, a slight twill defect will be formed, which cannot meet the needs of customers. In serious cases, the warp will directly cause the strip to deviate in the furnace

[0003] Usually, when cold buckling of ultra-deep drawing wide-width plates occurs, the strength of the strip steel entering the cold section will be increased by reducing the annealing temperature in the soaking section, thereby increasing the buckling resistance, or changing the microstructure by adding alloy elements, but such The measures can not completely eliminate the cold warp, but will also increase the yield strength of the strip steel, which cannot meet the stamping demand of the terminal; in the case of severe warp, it may even break the strip in the furnace, and it can only be shut down for 3- 4 days processing

[0004] To sum up, the problem of cold warping of ultra-deep drawing wide-width plates not only leads to unqualified product quality, but also seriously affects the production efficiency and production stability of the continuous annealing unit