Method for freezing automatic sequencing rolling pass of plate of moderate thickness

Abstract

The invention provides a method for freezing automatic sequencing rolling pass of a plate of moderate thickness. The method comprises the steps that a dialog box is set, a frozen thickness value is input, and an optimum pass rule of conventional billets with the rolling thickness being smaller than or equal to 6.5mm is locked; a frozen thickness is added to parameters of an operator inputs function in a secondary picture of a rolling mill; if the thickness of the rolled steel plate is smaller than the input frozen thickness, the total of remaining passes of the steel plate is not changed any more; if pass change occurs before freezing, the frozen thickness is maintained at the frozen thickness when multiple passes exist; if when the frozen thickness is controlled in a relatively small range, increase or decrease of passes occurs before the current rolling pass thickness is greater than the frozen pass thickness, then the frozen thickness value is set in a larger range. The method can be used for effectively controlling the pass rule, and while the quality of the steel plate is improved, the rolling success rate of a steel plate with a small specification with the thickness being smaller than or equal to 6.5mm is improved from 73% to 93%.

Description

technical field [0001] The invention belongs to the technical field of automatic control, and in particular relates to a method for freezing automatic programmed rolling passes in the medium and thick plate rolling process. Background technique [0002] For medium and heavy plate mills when rolling thin-gauge steel plates, especially limit-gauge steel plates with a thickness of 6.5mm and below, during the rolling process, due to rapid temperature changes, the actual rolling force deviates from the pre-calculated rolling force Larger, this leads to frequent changes in the second pass procedure, and this change mainly occurs in the last 3 to 5 passes. In response to this situation, the post personnel control the rolling by adjusting the unit rolling force. [0003] According to the current situation, the changes in the last few passes directly affect the change of the roll gap of the steel plate during the rolling process, resulting in unreasonable reduction procedures for ca...

AI Technical Summary

Problems solved by technology

[0003] According to the current situation, the changes in the last few passes directly affect the change of the roll gap of the steel plate during the rolling process, resulting in unreasonable reduction procedures for calculating the remaining passes, making it difficult to control the shape of the steel plate during the rolling process. It is very easy to have center wave shape or edge wave shape, serious bending or even frame scraping, which brings great hidden danger to the safety of rollers and other equipment

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