JPS56141907A - Thickness controlling method - Google Patents

Abstract

PURPOSE: To control the thickness correspondingly to the interval of skid masrk of the slab after extracting from the heating furnace in order to improve the accuracy of thickness, by stopping the slab at a fixed position upon the table on the feed-in side of the heating furnace.

CONSTITUTION: A slab 12 is stopped at a fixed position A upon the table 11 on the feed-in side of the heating furnace 13, and is charged into the heating furnace 13 for heating. At this moment, the controller 20 stores the data on the length of slab 12; besides, the stopping point A of the slab 12 is fixed and the interval l of the skid marks is a constant value, so that the controller 20 easily catches the position of skid mark of the slab 12. Next, if the slab 12 is rough rolled by the roughing stand group 16 and is bitten by the final roughing stand 16a, the speed detector 21 inputs the speed signal to the counter 22. Then, the counter 22 makes up a pitch suitable for controlling the rolling process for a size smaller than the interval l of the skid marks, and inputs it as the thickness controlling pitch to the controller 20. On the other hand, since the position of the skid mark of the slab 12 is being caught, the control pitch just corresponding to the skid mark can be discriminated, so that the elimination of thickness variation at the point of the skid mark becomes possible.

COPYRIGHT: (C)1981,JPO&Japio