CUTTING METHOD OF BILLET

PURPOSE:To decrease the loss equation of billets by calculating the loss quantity by conditioning according to the casing history which the billets received for each of the billet and adding the same to the required length of the product. CONSTITUTION:It is assumed that the front end of a strand coincides with the front edge in the small area of an index (i) at the point of the time when the cutting by a cutting machine 6 ends. A computer calculates the number of the small areas to be cut out next as D0/l when the required length of the product is assumed to be D0. The computer reads out a correction factor from the memory region attached with said index and calculates the loss quantity D1 by conditioning when the small area as the object of cutting is determined. The cutting length D is determined by utilizing the D1. The computer compares the output data from a device 5 for measuring the pass length of the billet and the cutting length D when the length D is determined. The computer emits a cutting command to the machine 6 when the extent of the movement of the strand after the previous cutting coincides with the D. The billet cut out in such a manner has the length added with the loss quantity by conditioning and the deficiency in the unit weight by the subsequent conditioning stage is obviated.