METHOD FOR CONTROLLING THICKNESS OF STRIP IN FLYING GAUGE CHANGE ZONE DURING TRAVELING IN CONTINUOUS COLD ROLLING PROCESS

摘要

PURPOSE: A method for controlling thickness of a strip is provided to reduce an off gauge length that is deviated from a target thickness without a separate additional system during thickness controlling in the non-control section. CONSTITUTION: In a method for controlling thickness of strip in flying gauge change zone during traveling in continuous cold rolling process, the method comprises the steps of measuring thickness deviations of a hot rolled strip using a thickness gauge(1) at the entrance side of a stand No. 1, calculating corrected roll gaps and roll speeds at a PLC(programmable logic controller)(5) level using the measured thickness deviations of the hot rolled strip, and correcting thickness of the hot rolled strip to the calculated roll gaps and roll speeds; and controlling the thickness by operating a feed forward AGC(automatic gauge controller)(8) and a feedback AGC(9) to the stand NO.1 right after correcting the roll gaps and roll speeds, wherein the thickness deviations are measured 10 times with a continuous period of 20 msec in the time lapse of 500 msec after the welding part passes the thickness gauge at the entrance side of the stand No. 1.