| 摘要 |
<P>PROBLEM TO BE SOLVED: To reliably and effectively perform floatation of inclusions as compared with before using a tundish in which a weir is installed including a wall part and a canopy-like part horizontally projected on an upper end part of the wall part. <P>SOLUTION: In continuous casting of steel cast slabs, the tundish 1 is used including the weir 7 with a rectangular outer shape disposed therein having a wall part 8 extending upward while surrounding the molten steel injection part from four directions and the canopy-like part 9 horizontally projected facing the molten steel injection part side at the upper end part of the wall part between a molten steel injection part 5 and a molten steel outflow part 6, and one or more cutouts 10, wherein the steel cast slabs are continuously cast by controlling injection of molten steel so that an injection flow rate Q of molten steel to the tundish, an injection flow rate m and an injection speed u of the molten steel into a mold with respect to an opening part area S1 of the upper part of the weir, an opening area S2 of the cutout, a volume V of a space surrounded by the weir, a length X of a long side of the rectangular outer shape of the weir, and a length Y of a short side of the rectangular outer shape of the weir satisfy the expression (1) 3.0≤(m×u)×(S1/Q)×(1/V)×(X/Y)×(1+S2)≤50. <P>COPYRIGHT: (C)2013,JPO&INPIT |
