Steel castings

Coated sand casting refers to the casting method of covering a layer of solid resin film with molding sand or core sand before molding. There are two kinds of coating processes: cold method and hot method. The cold method is to dissolve the resin with ethanol, add additives in the process of sand mixing, so that both of them are coated on the surface of sand particles, and the ethanol volatilizes to obtain coated sand; This method is to preheat the sand to a certain temperature, add resin to melt, mix to make the surface of the sand coated, add water solution and lubricant, cool, crush and sift to obtain coated sand. Generally used for steel and iron castings. The coated sand casting mainly uses natural quartz sand as raw sand and thermoplastic phenolic resin and reinforcing agent as raw materials. According to the different technical needs of users, the curing rate, demoulding property, fluidity, collapse property, casting surface finish, storage and other ratios shall be properly adjusted. Coated sand casting is one of the molding materials for automobiles, tractors and hydraulic parts.