Patent ID: 8302440

Claim:
A thickness control apparatus of a reversing rolling mill that rolls a material according to a pass schedule consisting of a plurality of passes, the thickness control apparatus comprising: an entry thickness gauge that is installed on an entry side of the reversing rolling mill and measures the thickness of the material to be rolled, entry material speed detecting means for detecting speed of the material to be rolled on the entry side of the reversing rolling mill, mill entry thickness detecting means for tracking thickness measured by the entry thickness gauge based on the speed of the material to be rolled detected by the entry material speed detecting means and for detecting thickness on the entry side of the reversing rolling mill, a position detecting device that detects a roll gap of the reversing rolling mill, mill delivery thickness calculating means for calculating thickness on a delivery side of the reversing rolling mill based on the thickness detected by the mill entry thickness detecting means and the roll gap detected by the position detecting device, pass compensation amount calculating means for calculating a pass compensation amount based on the pass schedule, a roll force detecting device that detects roll forces of the reversing rolling mill, and reference roll force calculating means for calculating a reference roll force at the start of a next pass, based on (i) the thickness detected by the mill entry thickness detecting means, (ii) the thickness on the delivery side of the reversing rolling mill calculated by the mill delivery thickness calculating means, (iii) the compensation amount calculated by the pass compensation amount calculating means, and (iv) the roll forces detected by the roll force detecting device, wherein the reference roll force calculated by the reference roll force calculating means is set in a position control device.