| 摘要 |
PURPOSE:To promote the slagging of powder and to improve the surface quality of a cast slab by surrounding almost horizontally molten metal by acting electromagnetic force to the molten metal poured into a mold from a nozzle at the initial stage of casting and increasing the heat supplying quantity to the powder supplied on the upper part of molten metal. CONSTITUTION:The molten steel 10 is poured into the mold 2 from a tundish, as a dummy bar head 18a is descended. And, when the dummy bar head 18a has reached at the lower end of the mold 2, the electromagnetic force is acted to the molten steel 10 in the mold 2 by electric magnets 14a-14d. Then, the molten steel 10 is almost horizontally circulated toward the arrow mark (b) direction and stirred. Next, further the dummy bar head 18a is continued to descend, and the cast slab is drawn from the mold 2 and cooled by a cooling device. Therefore, the heat supplying quantity to the powder 20 is increased and the slagging of powder 20 is promoted and so defect caused by inclusion in the cast slab is not developed by intervention of the powder 20 in solidified shell 24 at meniscus part 22. |
