Large acceleration control method for ensuring finish rolling temperature

Abstract

The invention discloses a large acceleration control method for ensuring the finish rolling temperature, and belongs to the field of temperature control in the rolling process. The control method aims to meet the control requirements of different types of steel, improve the production capacity of a rolling mill, shorten the production time and ensure the stability and the uniformity of finish rolling temperature. The control method comprises the steps that two points are generated in the length direction of strip steel; according to the information of the points, a finish rolling temperature calculation value and a speed calculation value of each point are calculated, and the sensitivity coefficients of the temperature/speed are calculated; the temperature deviation between the calculated values of the finish rolling temperature of the points and the target values when considering that cooling water between adjustable machine frames reaches the limit capacity are calculated, and the speed variable quantity required by the points to reach the target temperature are calculated by combining the sensitivity coefficients of the temperature/speed; iteration calculation is carried out repeatedly until the finish rolling temperature of the points approaches the target temperature; and finally the regional length of the large acceleration of the strip steel is obtained. The method has the advantages that the contradiction between finish rolling temperature control and rolling rhythm improvement can be solved, the production time can be shortened, and the production capacity of the rolling mill can be improved.

Description

technical field [0001] The invention belongs to the field of temperature control in the rolling process, and in particular relates to a large-acceleration control method for ensuring the finish rolling temperature. Background technique [0002] The finish rolling temperature is one of the key factors in the quality control of hot-rolled strip, which not only affects the microstructure and properties of the rolled strip, but also affects the metallographic structure and mechanical properties of the rolled strip. Therefore, in order to realize the temperature control of the finish rolling, it is necessary to ensure that the strip head reaches the target temperature and the uniformity of the finish rolling temperature over the entire length of the strip to meet the physical properties of the strip throughout the length. [0003] Due to the different residence time of the strip steel in the air, the finish rolling temperature of the strip steel is different in the whole length. ...

AI Technical Summary

Problems solved by technology

[0004] At present, it is generally used to fix the cooling water between the racks and adjust the acceleration to eliminate the temperature difference between the head and the tail, in order to achieve uniform temperature at the head and tail of the strip steel, but because the speed increases not only reduces the heat loss, but also increases the plastic deformation heat, so If the speed increase is too fast, the temperature of the strip will be too high to meet the control requirements, resulting in the failure to increase the rolling speed, which affects the improvement of the rolling rhythm, and the stability is poor; and the fixed acceleration is used to adjust the cooling water between the stands. , when the finish rolling outlet pyrometer detects the signal, the rolling mill will carry out rolling with a given large acceleration value, shorten the tail’s residence time in the air, and increase the finish rolling temperature of the tail, so as to maintain the strip’s full-length finish rolling constant temperature

In the actual production process, the use of high-acceleration rolling is beneficial to improve the production capacity of the rolling mill, but the final rolling temperature of the strip will gradually increase from the head to the tail along the length direction, which exceeds the control requirements, which is not conducive to the final rolling Temperature control, which conflicts with the temperature control of finishing rolling

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