PURPOSE: To prevent short-term fusion loss of porous brick and a steel leak accident by covering the brick with dense brick by monoblock molding so that a brick layer whose porosity is almost intermediate between the porosity of the porous brick and that of the dense brick is formed at the brick interface.
CONSTITUTION: Porous brick 12 is covered with dense brick 11 by monoblock molding to form circular gap 15 for feeding inert gas between the lower peripheral part of brick 12 and brick 11 as well as to form brick layer 14 whose porosity is intermediate between the porosity of brick 11 and that of brick 12 at the brick interface. Gas circulation opening 16 leading to gap 15 is also formed through brick 11. The resulting nozzle is attached to the bottom of a molten steel container. When molten steel in the container is discharged through nozzle opening 13, penetration of the steel into the vicinity of brick 12 is inhibited, thereby preventing local fusion loss of brick 12. A predetermined amt. of inert gas can be blown into the steel at a predetermined internal press. through gas blow pipe 17.
TAKAHASHI SHIYOUICHI
ITOU YUUGO
WATANABE TAKASHI
