BINDER FOR MOLDING SAND AND MANUFACTURE THEREOF, REGENERATE-RECOVERING METHOD, MOLDING SAND AND MANUFACTURE THEREOF AND MOLD AND MOLDING METHOD AND SHAKE-OUT METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide the title method, with which the resource and the energy can be saved and the harmony with the environment can be obtd. by adding alcohol to sodium silicate aqueous solution and mixing and drying. SOLUTION: Water is added to sodium silicate and stirred, and alcohol is added and mixed to form sol-state. Gelled SiO2 obtd. by drying gelled SiO2 precursor produced by removing solvent with an evaporator etc., is used as binder for molding sand. Sand and the binder are kneaded to make molding sand. The blending ratio of the sand and the binder is desirable to be (5-6):1. It is desirable that alcohol is added into sodium silicate containing sand and mixed and dried to make the molding sand. The molding sand is heated while holding at filling state to make a mold. Warm water is sprayed to the mold and shaken out and the sand and the binder are separated and regenerate- recovered. As the casting method using this mold, the shell mold process is suitably used.