Vacuum cast is also called “vacuum seal modeling of casting”, “reduced pressure molding casting”. It is different from the traditional sand mold casting. Its molding material is the binderless dry sand, and combine the vacuum technology with sand mold casting, seal the cavity surface and back of sand mold by the plastic film, with the help of vacuum suction to produce negative pressure, cause the internal-external pressure to make the sand to the mold. The process of vacuum cast is also managed by core setting, mold closing, pouring. When the casting is solidification, relieve pressure or stop air bleed, the sand melting and casting is formed. This process is vacuum cast.
Vacuum cast has some performances and advantages:
1.The casting surface is clean and bright, clear outline, size accurate, mold’s hardness uniform, drawing easy.
2.The equipment is simple, and the invent fee is relatively little, the sand witch we use to form mold can be employed many times.
3.Mold and sand box have a longer life.
4.Make full use of metal,
5.Improve the work environment, and reduces the labor intensity of worker.
So, the vacuum cast is the best cast technological process. The emergency of this technology to play an important role in the casting.