METHOD FOR MANUFACTURING HIGH-PURITY STEEL CASTING, AND TUNDISH

摘要

The flotation separation of inclusions in molten steel is performed with increased certainty and efficiency in comparison to conventional methods using a tundish having a weir consisting of a wall part and an eave-shaped part horizontally extending from the top edge of the wall part. Using a tundish 1 in which a weir 7 consisting of a wall part 8 extending so as to surround a molten steel charging position, an eave-shaped part 9 horizontally extending from the top edge of the wall part and at least one notch 12 is placed at a position between the molten steel charging position 5 and a molten steel discharge port 6, a steel cast piece 14 is continuously cast under conditions such that the height H of the upper surface of the molten steel in the tundish and the flow rate Q of the molten steel charged from the ladle into the tundish satisfy expression (1) below, where h represents the height of the weir, S represents the area of the upper opening of the weir, L represents the distance between the front edge on the molten steel charging position side of the eave-shaped part and the surface on the short side of the tundish, and W represents the distance between the front edge on the molten steel charging position side of the eave-shaped part and the surface on the long side of the tundish. 3.50 ‰¦ H - h × S × Á Q 1.37 - 0.6 + 7 L 6 × S × Á Q 1.37 + 7 �¢ W 6 × S × Á Q 1.37 ‰¦ 9.50