JPS577302A - Controlling method for rolling mill - Google Patents

Abstract

PURPOSE: To prevent the roll surface from being hurted, by driving upper and lower rolls of a PV mill at an equal speed, and by driving these rolls at differential speeds only when a sheet material is passed the roll gap.

CONSTITUTION: Before a material 1 to be rolled is bitten by a rolling stand, upper and lower rolling rolls 2a, 2b are driven at an equal speed by a rolls' circumferential speed ratio computer 11 dand a rolling speed setter 10. when the material 1 is bitter by the raolling stand, the compiter 11 gives the set points S₃, S₄ for the speeds of upper and lower rolls 2a , 2b to roll speed setters 9a, 9b in order to obtain a desired product; hereby, the upper and lower rolls 2a, 2b are driven at differential speeds, and practice a PV rolling work. When the tail end of the rolled material 1 drops out of the rolling stand, a tail end detector 13 detects the dropout of the tail end of the material 1, and the computer 11 gives an equal set point of the circumferential speeds to the roll speed setters 9a, 9b of upper and lower rolls 2a, 2b which are then switched to practice the equal roll speed rolling work.

COPYRIGHT: (C)1982,JPO&Japio