Method for preventing thin strip steel from being fractured at start moment

Abstract

The invention discloses a method for preventing thin strip steel from being fractured at the start moment. The method is applied to a cold continuous rolling unit. The method comprises the steps thatrolling force, formed at the stop moment, of the cold continuous rolling unit is acquired as memory rolling force; then, when roller replacement of the cold continuous rolling unit is completed and each roller gap is in the opened state, current winding tension corresponding to the start moment is determined, wherein the current winding tension is 1.5-3 times set winding tension, and furthermore,the covering phenomenon of a rolling mill section can be eliminated; and in addition, corresponding current actual rolling force, formed at the start moment, of each rack of the cold continuous rolling unit is determined based on the memory rolling force, and each rack of the cold continuous rolling unit is controlled to conduct downwards-pressing according to the corresponding current actual rolling force, formed at the start moment, of each rack, wherein the current actual rolling force of the first rack, the current actual rolling force of the second rack, the current actual rolling force of the third rack and the current actual rolling force of the fourth rack of the cold continuous rolling unit each accounts for 90-95% of the memory rolling force. By means of the method, the strip steel can be prevented from being fractured due to the excessively-large rolling force, thus strip fracturing of a rolling mill is avoided, and the cold continuous rolling unit is controlled to be started.

Description

technical field [0001] The present application relates to the technical field of continuous cold rolling, and in particular to a method for preventing thin strip steel from being cut off at start-up. Background technique [0002] In the production process of the cold tandem rolling mill, roll changing is one of the daily contents, and the production of thin strip steel after the roll changing is very prone to the accident of starting the car and breaking the strip. The rolling process just started is an unsteady state, and it is also the stage where various factors and parameters change most violently. The problem of sheathing and belt breakage caused by the wave shape between the racks and insufficient tension is particularly prominent every time the start-up occurs, especially when encountering Some thin-gauge steel strips (thickness less than 0.6mm) are prone to broken belt accidents. Broken belts not only cause parking to affect production, but also have a great impact ...

AI Technical Summary

Problems solved by technology

The rolling process just started is an unsteady state, and it is also the stage where various factors and parameters change most violently. The problem of sheathing and belt breakage caused by the wave shape between the racks and insufficient tension is particularly prominent every time the start-up occurs, especially when encountering Some thin-gauge steel strips (thickness less than 0.6mm) are prone to strip breakage accidents

Broken belts not only cause parking to affect production, but also have a great impact on the yield

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