JPS6418575A - Detection of slab cutting - Google Patents

Abstract

PURPOSE:To detect the cutting completion of a slab correctly and easily with good timing by feeding on electricity to a slab from the table rolls before and behind the cutting line position of the slab, detecting the electrical change at the cutting finish period and comparing it with the set value. CONSTITUTION:In the case of making a cast slab 5 cut in the specified length by cutting a continuous cast slab 7 by a cutting face 6 with a torch blow pipe 3, the fore and aft table rolls within the moving range of the torch blow pipe 3 are taken as a ground insulating driving rolls 2 and a roll collector brush 1 is fitted to fetch a lead wire 8. A power source is fed from a power source unit 10 by connecting this lead wire 8 to an electrifying roll switching device 9, the feeding to the earth side is performed via a current detecting device 11 and dummy resistance 12 and the continuous cast slab 7 is brought into contact with an earth conducting non-driven roll 4. The current value In of a current route is detected by a current detection circuit 11 with this composition, compared with the set value Id of a detection level setter 13 by a comparator 14 and in the case of In<Id a cutting completion signal 15 is outputted. The cutting completion of the slab is thus detected correctly and easily.