Rolling method used for rolling strip steel of reversible mill

Abstract

The invention discloses a rolling method used for rolling strip steel of a reversible mill, which can shorten the length of the worse parts of the thicknesses of the strip steel head and tail and improve the yield rate. Four stages of starting, accelerating, normal rolling as well as decelerating and stopping are comprised in each rolling path; at the beginning of each rolling pass, the automatic control function of the reversible mill is firstly closed and then the reversible mill is started to roll at a minimum rolling speed designed for the reversible mill; when the reversible mill is regulated and pressed down manually, the thickness deviation of the rolled strip steel is cotrolled in the reasonable range, then the automatic control function of the reversible mill is opened, the reversible mill is accelerated to the normal rolling speed to roll. As the manual and automatic operations are combined, the control precision of the thickness of the strip steel head is improved, the length of the worse part of the thicknesses of the strip steel head is shortened, the product yield rate is improved, and the rolling method is mainly suitable for the reversible mill.

Description

technical field [0001] The invention relates to the field of steel strip rolling, in particular to a rolling method for rolling steel strips in a reversible rolling mill. Background technique [0002] The rolling process of a cold-rolled strip reversing mill usually includes four stages: mill startup, acceleration, normal speed rolling, and reduced speed shutdown. Such as figure 1 As shown, the two sides of the reversing rolling mill are respectively arranged with thickness gauges, steering rolls and coilers. The strip steel is uncoiled by one of the coilers, passed through the rolling mill and coiled by the other coiler, and rolled to the required thickness after repeated rolling for multiple passes. Due to the characteristics of the reversing rolling mill, between the first thickness gauge, the second thickness gauge and the rolling mill, there are parts with lengths LL and LR that cannot be rolled, and the thickness of these two strips is always the original plate thick...

AI Technical Summary

Problems solved by technology

[0003] When the existing reversible rolling mill rolls strip steel, it works in the automatic control mode immediately after the rolling mill is started. Since the thickness of the strip steel with the length LL or LR between the thickness gauge and the rolling mill is always the original plate thickness, it will inevitably cause the rolling mill to automatically Overshoot when adjusting the pressing, resulting in ultra-thin strip thickness after rolling

However, after the ultra-thin strip steel is measured by the thickness gauge, the follow-up automatic control will inevitably cause overshooting during the automatic adjustment of the rolling mill, resulting in an ultra-thick strip thickness after rolling.

Such a vicious cycle causes the length of the strip head and tail thickness to be too long, usually exceeding 100m, which reduces the strip yield

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