| 摘要 |
PURPOSE:To obtain the casting mold in a short period of time and to improve production efficiency by providing a hermetic type housing having an inlet and outlet for gas via a gas passage on the outer side of an air permeable housing. CONSTITUTION:The air permeable housing 1 is provided via the gas passage 4 in the hermetic type housing 3 having the inlet and outlet 5 for the gas and a combustible expendable pattern 6 is housed in this air permeable housing. Air permeable refractories 10 in the form of a slurry are packed into the excess space thereof and are dried; thereafter, gaseous oxygen is force fed from the outer side of the air permeable housing on the inner side thereof from the inlet and outlet of the above-mentioned hermetic type housing through the gas passage therein into this housing to burn and expend the above-mentioned expendable pattern on the inner side thereof to form a cavity in the trace thereof. The inside surface layer of the above-mentioned air permeable refractories is simultaneously cured by this combustion to form a casting mold layer. A molten metal is poured into this cavity while a negative pressure is maintained in the above-mentioned gas passage. After this molten metal is cooled, the above-mentioned casting mold layer is broken. Even if the casting mold is formed to an intricate shape or a thin shape, the precise product having the same shape as the shape of this mold is easily cast in this way. |
