METHOD FOR PROMOTING HARDENING OF CASTING SAND MOLD

PURPOSE:To promote hardening of a sand mold, particularly in the winter season by supplying pressurized high temp. gas in a sand mold. CONSTITUTION:Two pieces of porous plates 3 are fitted as facing in a flask 2, and pipes 5 communicating to gap 4 between each porous plate 3 and the flask 2 are fitted. Into space formed with a base board 1, the flask 2 and a pattern 6, the molding sand is packed to form the sand mold 7. As the molding sand, silica sand mixing organic binder of furan resin, etc., and hardening agent is used. The pressurized high temp. air at the prescribed temp. and pressure is supplied from the pipe 5. The pressurized high temp. air heats the sand mold 7 to rapidly harden the sand mold, and the pattern 6 is easily separated from the sand mold 7. As a device for obtaining the pressurized high temp. air, the heat exchanger is used, and it is desirable to be the pressurized high temp. gas, in which does not mix moisture in combustion gas. By this method, the hardening of the sand mold is promoted.