Plate strip rolling thickness control method based on mill spring characteristic curve

Abstract

The invention discloses a plate strip rolling thickness control method based on a mill spring characteristic curve and belongs to the technical field of automatic control of plate strip rolling. The control method for determining thickness gage AGC (automatic gage control) comprises steps as follows: 1, inputting a stiffness coefficient Km of a mill and a plasticity coefficient Q of a plate strip, and determining a proportionality coefficient K of a thickness control object; 2, acquiring a rolled arch spring characteristic curve through a forced-contract experiment, regressing rolled piece spring curve according to off-line data, acquiring a total mill spring characteristic curve equation, and determining a mill spring amount Str; 3, determining a thickness deviation value delta h of a mill outlet according to actually measured rolling force, an actually measured roll seam, locking rolling force and a locking roll seam on the basis of the mill spring amount Str determined in the prior step and in the principle of thickness gage AGC of the mill spring characteristic curve; 4, determining an adjustment amount delta Sgm of thickness gage AGC with the consideration of the pressing efficiency of the mill. The influence of the stiffness coefficient of the mill on the spring equation is effectively avoided, and the thickness accuracy of plate strip rolling in the automatic control process is improved.

Description

technical field [0001] The invention belongs to the technical field of strip rolling automatic control, in particular to a strip rolling thickness control method based on a rolling mill bounce characteristic curve. Background technique [0002] In the strip rolling process, including steel strip, aluminum strip, copper strip and other rolling processes, one of the most commonly used thickness control methods is to use the bounce equation to indirectly calculate the thickness of the deformation zone, and then adjust the hydraulic roll gap of the rolling mill Feedback control of strip thickness, usually this thickness control method is called thickness gauge AGC (AutomaticGageControl). [0003] The basis of automatic thickness control is the elastic-plastic curve during rolling. The relationship between the calculated strip thickness h, the actual roll gap width S and the actual rolling force P is shown in the bounce equation: [0004] h = S ...

AI Technical Summary

Problems solved by technology

[0013] The prerequisite for the thickness gauge AGC to calculate the thickness by using the rolling mill bounce equation is that the rolling mill bounce equation is an accurate linear equation, that is, the rolling mill stiffness coefficient K m It is a constant under different rolling forces, but because there are gaps between parts of the rolling mill and bearings, etc., the bouncing amount of the rolling mill and the rolling force must have a nonlinear relationship

This will cause wrong adjustment of thickness control, and even wrong direction of roll gap adjustment.

So far, when the traditional thickness gauge AGC is used for control, there is often a large difference between the calculated thickness deviation and the actual thickness deviation or even the opposite sign, resulting in inaccurate or even wrong adjustment of the thickness control

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