Hexin precision casting is refers to the input of the high pressure water by high pressure water pump, the spray gun nozzle to form high pressure jet, centered on the casting surface sand and sand core and a kind of method of deoxidization.Mainly suitable for the surface of the larger iron deoxidization and core.Hexin precision casting sand is brought a certain temperature of precision casting products into the pool, into the hot water heating vaporization of sand mold and sand core, continue to be as the water vaporization and steam heating, pressure increasing, the "collapse" of sand mold and sand core from the casting surface and inner cavity slipping out, so as to achieve the aim of deoxidization.