The present invention relates to a method for
casting a vacuum sub-pressure
solid resin sand molding lost mould, and belongs to the
casting technical field, in particular relates to a method for
casting a vacuum sub-pressure lost mould, which mainly comprises the steps such as molding,
coating, sand-box patternmaking, tapping, pouring,
vacuum pumping, heat preservation and cooling, and adopts the casting steps: a. foam plastic mould is made according to the shape of the casting piece; b. the outer surface of the foam plastic mould is coated with
coating; c. the foam plastic mould that is coated with
coating is arranged inside a sand box, and the patternmaking is performed with resin sand; d. the sand box after the patternmaking is arranged inside a tapping device so as to tap the patternmaking sand inside the box and to be dried; e. while pouring the iron liquid, the sand box is vacuum pumped synchronically by a
vacuum pumping machine, and the gas that is obtained from the
vacuum pumping is discharged after being purified; f. after the pouring is completed, the vacuum pumping is stopped, and the casting piece is taken out to be arranged inside a heat-preservation oven, so that the temperature is increased to 1100 DEG C, and the casting piece can be produced after the heat preservation and cooling. The method of the present invention has simple process, precise
processing, easy operation and low production cost.