PREVENTION OF OUTFLOW OF SLAG FROM TAP HOLE OF VESSEL FOR MOLTEN METAL

摘要

PURPOSE:To prevent effectively the outflow of slag floating on a molten metal and to eliminate intrusion of the slag into the molten metal by closing a tap hole with a planar body at the end period of tapping of the molten metal. CONSTITUTION:A floating valve 8 which is suspended and held by means of a wire rope or chain 7 is lowered and positioned to the boundary between slag 6 and a molten steel 2 to prevent generation of a vortex just prior to generation of the vortex. The valve 8 is also lowered as the level of the molten metal decreases while said positional relation is maintained. The valve 8 lands onto a nozzle 4 at the end period of tapping. The valve 8 is then slightly moved upward to tap the remaining molten steel 2' and thereafter a sliding nozzle 3 is closed. The outflow of the slag is thus prevented.