| 摘要 |
PURPOSE:To improve the productivity of continuous casting and the quality of a cast slab by crushing useless steel produced in a continuous casting direct rolling mill to granule fine steel pieces and adding the fine steel pieces into molten steel through a supplying nozzle after removing their oxide film. CONSTITUTION:The continuous casting apparatus cools the molten steel 11, which is poured between one pair of metallic belts 4, 4 ' shifted as circulating from a nozzle 2 of tundish 1, by cooling pads 6, 6 ' at back faces of the belts 4, 4 '. Next, the solidified cast slab 13 is sent to a cutter 7 and the rolling line of tandem mill 9 providing heat holding zone 8 to roll to a strip. Then, the useless steel produced at the continuous casting apparatus or succeeding production process is crushed into the granule fine steel pieces by a crusher 20. In succession, the fine steel pieces removing oxide film by a reducing treatment device 21 are supplied into the molten steel 11 through the supplying nozzle 23. In this way, the productivity of continuous casting is improved and the cast slab having good quality is produced. |
