PURPOSE: To make width variations of a stock to be rolled on the outlet side of a finish rolling mill small by detecting respective deviation values in rolling loads, screw down positions, and forward tensions from each of criterion values at an (i-1)th and an (i)th stands and an absolute roll speed at the (i-1)th stand.
CONSTITUTION: A rolling load deviation, a screw down position deviation, and a roll speed of an (i-1)th stand 12 are inputted to a thickness deviation computing element 30 to find a thickness deviation ΔHi of a strip 10 entering an (i)th stand 14. Then, respective deviations of rolling loads, screw down positions, backward and forward tensions of the stand 14, and the thickness deviation ΔHi found by the computing element 30 are inputted to a temp. deviation computing element 32 so as to find a temp. deviation ΔTi of the strip 10 at the stand 14. The temp. deviation ΔTi and a roll speed deviation ΔVp of the final stand 18 are inputted to a tension correction amount computing element 34 to find a forward tension correction amount for the stand 14 and the correction amount is inputted to a tension controller 36 to correct a tension.
ASANO KAZUYA
ABE HIDEO
