| 摘要 |
PURPOSE:To form rough-shaped billets of good quality with a good yield by forming a slab to a dogbone-shaped intermediate slab through repetition of broadside screw- down by means of bull-head caliber thence passing the same through molding caliber. CONSTITUTION:A platelike slab 20 is heated to a predetermined temp. and is subjected to broadside screw-down by means of the bull-head calibers 12-1, 14-1 of rolling rolls 12, 14. This edging rolling is repeated to produce broadside spreading at both ends in the width direction of the slab, whereby the slab is formed to an intermediate slab 22 of a dogbone-shaped cross section. Thence, it is admitted into molding calibers 12-2, 14-2, whereby it is formed to a rough-shaped slab of a predetermined sectional shape. In this rolling process, box calibers 12-3, 14-3 are used depending upon need, besides bull-head calibers 12-1, 14-1. With this method, the rough-shaped slabs of good quality are obtained at high performance. |
