| 摘要 |
PURPOSE:To facilitate flow rate controlling of molten metal by bringing a lower refractory board having a nozzle hole of a small bore and an upper refractory board provided with a large diameter hole constituting the bottom part of a molten metal vessel into tight contact with each other and sliding the upper molding board. CONSTITUTION:The bottom part of a molten metal vessel 7 is constituted of an upper refractory board 5, and a large diameter hole 6 is provided. A lower refractory board 3 having a nozzle hole 4 of a small bore is provided in the lower part thereof and the board 5 is clamped in tight contact with the board 3 by means of arms 13 having coil springs 12. With the hole 4 of the board 4 held closed thoroughly by the board 5, molten metal is introduced into the vessel 7, and the upper refractory board is slided by an actuating rod 16 to communicate the hole 4 and the hole 6, thereby charging the molten metal through a sprue 18 into a mold 17. It is possible to control the discharge flow rate of the molten metal finely by adjusting the opening of the hole 4 finely by proper fine adjustment operation of the sliding movement of the board 5. |
