| 摘要 |
PURPOSE:To such away the excess water of a gypsum slurry and to easily form a casting mold having an intricate shape by disposing a pattern in the flash on an air permeable molding board and pouring the gypsum slurry into the flask while reducing the pressure in a water sucking chamber right under the molding board. CONSTITUTION:The pattern 1 is installed in the flash 3 on top of the molding board 2 in such a manner that the part of the pattern 1 between a blade 8a and a blade 8b contacts the molding board 2. The molding board 2 is formed by solidifying molding sand for casting a sand mold and has >=40 air permeability with large orifices and therefore, the air flows from the top surface of the molding board toward the bottom surface of the molding board when the pressure in the chamber 6 is reduced by a vacuum pump. The gypsum slurry 4 prepd. by mixing gypsum powder and water is poured into the flask 3 at the same instant. The excess water in the gypsum slurry 4 is then also sucked away together with the air and is removed in an arrow A direction. The slurry 4 is poured into the narrow part between the blades 8a and 8b by the pressure difference, by which the good gypsum mold is formed.
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