PURPOSE:To decrease the amt. of the molten metal to be sucked up and to improve productivity by disposing refractories so as to hang down to the central part of the sprue part ot the casting mold from the top end of the sprue part. CONSTITUTION:The circular columnar refractories 11 are disposed to the center of the sprue part 4 to hang down so as to have the spacings for the passage of the molten metal around the same without closing gates 5 around the sprue part. The casting mold 3 is put into a chamber and a snout 7 in the lower part of the sprue 4 is immersed into the molten metal. The pressure in the chamber is reduced to suck up the molten metal from a suction port 8 and to fill the molten metal in the cavity 6. The reduced pressure state of the chamber is released and the molten metal in the unsolidified state existing in the sprue part 4 is discharged by gravity after the molten metal of the gates 5 solidifies upon lapse of the prescribed holding time. The correspondingly smaller amt. of the molten metal to be sucked by as much as the refractories 11 is necessitated even if the sprue part 4 is formed to a large diameter to allow the simultaneous casting of many products. The productivity is thus improved.
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