Hot strip width control method by using looper tension measuring system infinishing mill

A high precision hot strip width control method has been developed in this study by applying an interstand looper tension measuring system at the fini shing mill stands. As the width deviation of hot rolled steel strip is clos ely related to abnormal increase in the interstrip tension, an on-line meas uring device of looper tension and a data analyzing system were developed i n this study. To determine dominant factors that will cause local width sho rtage, the logged data sets of bar width, bar thickness, looper tension, an d strip thickness along the strip length were correlated with the data set of strip width change. With the result of the correlation analysis, existin g sequence control logic and parameters for looper actuator were modified f or strip width quality and the gains of the looper control were refined for stable operation during the full passage of rolled strip. Tile on-line ten sion measurement and tension feedback control for the looper : system. impr oved the strip travelling stability and reduced strip width deviation in th e strip top end region. (C) 2001 Published by Elsevier Science B.V.