Online control method for finish rolling temperature of precision rolling strip steel

Abstract

The invention discloses an online control method for the finish rolling temperature of precision rolling strip steel and belongs to the field of temperature control of rolling processes. The second flow regulating variable or the cooling water flow regulating variable between machine frames is subjected to online optimization through a quadratic programming optimization algorithm, and the deviation between a calculated value and a target value of the finish rolling temperature is reduced. The method comprises the steps that a plurality of control points are generated on the strip steel in the length direction according to a control period; the deviation between the calculated value and the measured value of the finish rolling temperature of all the control points is calculated according to information of all the control points and the measured value of a pyrometer at a precision rolling outlet; a temperature calculating model is corrected according to the deviation, and the calculation precision is improved, at the same time, the deviation between the calculated value and the target value of the finish rolling temperature of all the control points is calculated; and according to the deviation value between the temperature calculated value and the target value, the second flow regulating variable or the cooling water flow regulating variable between the machine frames of all the control points is subjected to online optimization through the quadratic programming optimization algorithm, and the finish rolling temperatures of all the control points are made to meet the control requirements. By means of the method, the control precision of the finish rolling temperature of the strip steel is improved, the uniformity of the total-length temperature of the strip steel is guaranteed, and the finished product quality requirements are met.

Description

technical field [0001] The invention belongs to the field of temperature control in the rolling process, and in particular relates to an on-line control method for the finish rolling temperature of finished strip steel. Background technique [0002] Finishing temperature is an important parameter for the quality control of hot-rolled strip steel, which not only affects the deformation resistance and other rolling parameters of the rolled strip steel, but also affects the metallographic structure, mechanical properties and dimensional accuracy of the finished strip steel after rolling. Therefore, in order to meet the quality requirements of the finished strip steel, it is necessary not only to make the head of the strip steel reach the target temperature, but also to ensure the uniformity of the final rolling temperature of the strip steel throughout the length, so as to meet the requirements of the microstructure performance and dimensional accuracy of the strip steel through...

AI Technical Summary

Problems solved by technology

The former is easy to control the full-length temperature of the strip and has good uniformity, but because the increase in speed not only reduces heat loss, but also increases the heat of plastic deformation, so if the speed rises too fast, the temperature of the strip will be too high to meet the control requirements , resulting in the inability to increase the rolling speed, which affects the improvement of the rolling rhythm, and the stability is poor; the latter adopts a certain acceleration, which can improve the rolling rhythm and is beneficial to the rolling stability, but the response speed is slow, and it is prone to strip full Long-term temperature fluctuations

As the control standard of high-precision and high-performance steel is getting higher and higher, the traditional temperature control mode of finishing rolling can no longer meet the control requirements of the site

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