Loop control method of special thick steel at low temperature

Abstract

A loop control method of special thick steel at low temperature is disclosed, and aims to overcome the loop oscillation among precision rolling frames and ensure normal production of hot rolling. The method comprises the steps of: determining the control parameters of the loop among the frames by a first level computer according to the following formula if the target temperature at the strip steel precision rolling outlet is lower than 830 DEG C and the thickness of the product is greater than 7mm: Yn=Yn-1+Kp*{[1+TA / TN]*deltaYn-deltaYn-1}, wherein Yn is the additional quantity m / s of the loop height to the frame speed at sampling moment n; TA is program scanning time; TN is time of integration; Kp is proportional coefficient; deltaYn is loop height difference mm at sampling movement n; and transmitting downward by a second level computer to distinguish the loop tension set values of steels so as to give the torque of the loop.

Description

technical field [0001] The invention relates to an automatic control method of a hot strip rolling line. Background technique [0002] Because the finishing stand of the hot continuous rolling mill generally consists of 7 rolling mills, a hydraulic looper is arranged between every adjacent two rolling mills. The control of the finishing mill is realized by the first and second-level computers. The speed setting of each rolling mill and the setting tension of the looper are all calculated by the second-level model server according to the process requirements before the strip enters the rolling mill. The speed and looper adjustment of each rolling mill The control and so on are all completed by the first-level computer PLC, especially the adjustment between the speed of the rolling mill and the looper after the strip is threaded is completely realized by the first-level computer PLC. With the development of special steel varieties, when rolling low-temperature and thick-gauge...

AI Technical Summary

Problems solved by technology

With the development of special steel varieties, when rolling low-temperature and thick-gauge special steel, the speed of the finishing stand is very low (less than 2m / s) and the response characteristics are not good in the low-speed section, so the hydraulic looper adjustment and the rolling mill stand The speed adjustment does not match, resulting in the oscillation phenomenon of the 0#-5# looper between the finishing rolling stands. In severe cases, it will lead to direct scrap steel between the stands, which seriously affects the normal production of the rolling line and brings great economic losses to the enterprise.