| 摘要 |
A primary object of this invention is to provide a continuous casting method for carrying out reduction on a slab in a continuous casting machine, and by which the slab of excellent internal quality can be continuous-cast even if the casting speed is changed. This invention provides a method for continuous-casting a slab wherein upon continuous-casting a slab while reduction is carried out on the slab using a continuous casting machine with two stages of reduction rolls, each of the two stages consisting of a pair of the reduction rolls, and being arranged along a casting direction, a diameter of each of the reduction rolls being 1.2 to 2.0 times as much as thickness of the slab just before reduction with corresponding reduction rolls, the continuous casting machine including the reduction rolls and support rolls arranged between the reduction rolls, when a casting speed is reduced compared to a state where the slab is cast at a constant speed under combination of reduction with reduction rolls at a first stage on an unsolidified portion of the slab and reduction with reduction rolls at a second stage on a solidified portion of the slab; accompanying movement of a place of the slab where the solidification is ended upstream in the casting direction due to the reduction of the casting speed, the combination is switched to combination of reduction with the reduction rolls at the first stage on a portion of the slab at an end of solidification and the reduction with the reduction rolls at the second stage on the solidified portion of the slab. |
