Research And Application Of AGC Control System Of Bayi Iron&Steel 1750 Hot Strip Finishing Mill

Thickness accuracy is an important quality indicator of strip material.Automatic Gauge Control System is called AGC-system for short.It is an indispensable part of mill automation system.Through certain means to achieve the purpose of AGC-system,such as adjusting the roll gap to reach the anticipated target of the steel plate thickness.There are many ways of the realize AGC-system,there are also many factors influencing the accuracy of AGC-system,fluencial factors include material thickness changes,material properties changes,mill modulus changes,oil film on the backup roll changes,thermal expansion and wear of rolls,the influences of roll eccentricity,rolling speed changes,etc.For the different types of thickness control system,we analyze which factors are the key factors affecting AGC-system,so as to take actions accordingly.This article mainly discusses AGC control system of Bayi Iron&Steel 1750 Hot Strip Finishing Mill,this paper analyzes the control model of thickness control system and study the characteristics of six-hi single-stand reversing cold rolling mill by hydraulic pressure system.A model for the rolling force and rolling torque is investigated.If the finishing mill housing conditions(rolling force,rolling torque,rolling speed,etc.),material characteristics(the yield point of the material and temperature),rolling production line characteristics(maximum speed and acceleration of roller table,etc.)are permited,rolling load distribution is appropriately.Model parameters of the calculations have been carried out for the thickness control system of finishing mill rolling.At the same time,the rolling schedule is optimized.There are a lot of problems in the process of AGC control system of Bayi Iron&Steel 1750 Hot Strip Finishing Mill:Control rolling force deviate greatly;really achieved ±1000 KN,Rolling process is not steady,Too frequently adjustment;After roll changing,it take a long transition time from cold state to rolling steady state,capacity for self-directed learning is less powerful;For X80 the thick plate rolling,stability of looper control system is not ideal;lognitudinal thickness deviation of the strip is higher,the request of customers with high accuracy products can't be satisfied.This paper presents strategies and suggestions to the above problems through the research on AGC control system and the control parameters analysis.