| 摘要 |
PURPOSE:To prevent occurrence of an accident of molten steel leakage from inert gas introducing pipe caused by solidifying molten steel by arranging equaliz ing zone and gas passage so as to be possible to uniformly inject the inert gas and changing beads in the equalizing zone. CONSTITUTION:A porous brick 20 for upper nozzle 1 has a hole unit for nozzle hole 14, the equalizing zone 21 formed in the porous brick 20 and arranged so as to surround the nozzle hole 14 and the gas passage 22 connected with the equalizing zone 21 and for supplying the inert gas, such as N2 or Ar, into the porous brick 20 through the equalizing zone 21. Then, by this construction, the inert gas is blown into the nozzle passage 14 from the porous brick 20 under equalizing condition. Further, as many beads are closely packed in the equalizing zone 21, even if the erosion is progressed and reaches the equalizing zone 21, the molten steel solidifies at this part and the molten steel leakage from the inert gas introducing pipe can be prevented. |
