CASTING, MODEL FOR CASTING, AND METHOD OF CASTING

摘要

PROBLEM TO BE SOLVED: To provide a model for casting, capable of setting a solid lubricant in the prescribed position of a hole of a casting. SOLUTION: A model 31 used for casting a product consists of a model body 32 composed of a cylindrical expanded polystyrene and a solid lubricant 21 composed of graphite attached radially to the model body 32. The top 21b of the solid lubricant 21 is projecting from the inside perimeter 32a of the model body 32 toward the pivot of the model body 32 so that the top dips into casting sand of the sand mold. An enveloped casting unit is composed of the model 31 placed in the prescribed position of the model for the casting body. After covering the enveloped casting unit with the sand model, molten metal is poured into the sand model. The molten metal melts the envelop casting unit and fills in the sand model. A hardened casting is removed from the sand model and the inside perimeter surface of the hole, which is the enveloped casting part of the solid lubricant 21, is machined to the predetermined inside diameter.