PRODUCTION OF CASTING MOLD

摘要

PURPOSE:To eliminate the need for a binder to obtain initial strength and to prevent the collapsion of a mold in the stage of rapping by bringing a refrigerant into contact with a granular material which is made wet and packing the material onto a pattern surface while pregressing the process of freezing. CONSTITUTION:A driving source 2 for rotating a sand mill 1 is operated and molding sand is continuously supplied from a supply mechanism 6 and a chute 7 through a supplying port 5 into the mill 1. On the other hand, water is fed from a feed mechanism 8 into the mill 1 and is kneaded with the molding sand, thereby producing the wet molding sand. A refrigerant is supplied to the wet molding sand from a refrigerant supplying mechanism 9 into the mill 1 to progress the process of freezing the molding sand. The molding sand frozen like sherbet on progression of the freezing is accelerated by the compressed air to be ejected from a booster 12 and is sprayed and packed through a conveying conduit 13 and a nozzle 14 into a molding flask mounted therein with a pattern. The molding sand sprayed and packed onto the pattern freezes and solidifies and permits rapping when held for a specified time.