Method for controlling speed of hot continuous rolling strip steel loop at low loop position

Abstract

The invention discloses a method for controlling speed of a hot continuous rolling strip steel loop at the low loop position, and belongs to the field of automatic control of hot rolled steel of a metallurgy industry. When time of loop rising of the strip steel biting loop, located between every two adjacent racks of a finishing mill set, of a rear rack is delayed by 1 to 1.2 seconds, the angle of the loop is smaller than or equal to 13 degrees, and meanwhile the torque deviation of the loop is larger than 500, a loop system speed compensation value obtained through calculation of a first-class computer is superimposed to a host speed control reference value; the superimposed value is transmitted to a main transmission system-Siemens inverter SM150 through a PROFIBUS, and the main transmission system carries out automatic speed adjustment and control based on the superimposed value; and the aims of speed adjustment of a finishing mill host and control stability of the loop are achieved. According to the method, rolled strip steel is stably controlled, and meanwhile the influence of instability like loop strip steel loop loosening caused by mismatching of the host speed and loop system adjustment when the loop is located at the low loop position on rolling is avoided; the failure time is shortened; the strip steel product quality is ensured; and the good benefits are obtained.

Description

technical field [0001] The invention belongs to the field of looper automatic control of a hot strip rolling line. Background technique [0002] The response speed of the main drive system of the hot continuous rolling finishing mill is faster than the looper adjustment speed. Due to changes in the strip model setting and process incoming materials of the finishing mill, it is very easy to cause the looper to be at a low position at the initial stage of hot strip threading, that is, the looper angle is below 13°. Under normal rolling conditions, the angle of the looper is 25°. Therefore, under the control of the amount of the looper, when the looper adjusts and starts the looper, due to the faster speed of the looper compensation host, there will be a false looper of the strip, that is, the actual torque of the looper is smaller than that of the looper. Set the given torque, resulting in deviation of the strip, and in severe cases, it will lead to direct scrap steel between...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to ensure that the speed value of the looper compensation host in finishing rolling is compatible with the control of the hydraulic looper, and to solve the problem of false loops on the strip caused by the speed adjustment of the looper compensation host when the looper is started in the finishing mill , to ensure normal hot rolling production and product quality