PURPOSE: To prevent blowhole defects and to obtain a casting having high strength by disposing a chiller formed by bundling metallic bar-shaped pieces to a pattern surface corresponding to the surface of the casting requiring quick cooling and evacuating and sucking the evaporating gas of a consumable pattern through the spaces of the chiller.

CONSTITUTION: The bundle 5 of the metallic bars 4 is set in a reduced pressure chamber 2 and the bottom end faces of the bars 4, 4... contact tightly with the top surface of a metallic block 3. The pattern 6 consisting of foamed styrol is supported by the bundle 5 and porous ceramics 7 are packed on the pattern side 6 in the spaces between the respective bars 4, 4.... A casting mold 8 is formed by setting the pattern 6 on the bundle 5 and packing dry molding sand having fluidity without contg. a binder around the pattern 6. Water cooling pipes 13 are disposed under the block 3 and cooling water is injected from nozzles 14 to cool the block 3. On the other hand, the inside of the chamber 2 is evacuated by a vacuum pump, etc. through an evacuation port 15, by which the cooling of the casting and the discharge of the gas are simultaneously executed.