PURPOSE: To prevent the development of solidified material caused by the temp. drop at a valve seat part by arranging a seal part to molten metal so as to project into the stored molten metal side, forming the lower end part of a weighing valve rod as arching recessed shape and abutting the valve seat part on the weighing valve rod at the time of closing the valve.
CONSTITUTION: The valve seat part 81 having a molten metal discharging hole 65 is arranged as a part of a valve seat sleeve 27 at the tip lower part and the weighing valve rod 26 is arranged so as to be freely opened/closed to this valve seat part. The seal part to molten metal is arranged at the upper part side of the valve seat part 81 so as to project into the stored molten metal side and also the lower end part of the weighing valve rod 26 is formed as the arching recessed shape, and the valve seat part and the weighing valve part are constituted so as to mutually abut on each of them at the time of closing the valve. By this constitution, the heat receiving area on the valve seat part 8 is increased and the holding heat of the molten metal is easily conducted to the valve seat part 81 and the development of the solidified material is prevented. Further, even if the oxide is developed or there is the broken piece of the furnace lining, these are deposited on the bottom part 81c of the sleeve and the biting to the seal surface is prevented and the sealing performance is improved.
KAWASHIMA GENZO
MITSUYOSHI HIROAKI
