The invention discloses a negative-pressure vacuumizing pouring method for a high-pressure regulating valve
casting. The method includes the following steps that S1, a sand mold is closed and put intoa tool which is a box body with an opening formed in the upper end, an air suction cavity is formed in the lower end of the box body, and the air suction cavity is separated from the box body througha filter screen; S2, the space between the box body and the sand mold is filled with
dry sand; S3, after the spaced is full of the
dry sand, plastic is laid at the upper end of the box body, and thedry sand is laid on the plastic; S4, a
vacuum pump is started, and the air suction cavity is vacuumized; S5, pouring is conducted in the sand mold, and the
vacuum pump is kept to be started; and S6, after pouring is completed, the
vacuum pump is stopped. According to the method, the pouring speed is increased, the
mold filling time of the high-pressure thick-wall
casting is shortened, the qualityof the
casting is further improved, particularly, the shrinkage crack defects of the
chromium-
molybdenum steel shot casting of the high-pressure regulating valve are overcome, and the problem of structure segregation of the high-pressure thick-wall valve body casting is effectively solved.