Sand casting is a kind of traditional casting technology which takes sand as the main molding material to make the mold. Generally, gravity casting is used for sand mold, and low-pressure casting, centrifugal casting and other processes can be used when there are special requirements. Sand casting has a wide range of adaptability, small, large, simple, complex, single, mass can be used. The mold used for sand casting was usually made of wood, commonly known as wood mold. In order to change the defects of wood mold, such as easy to deform and damage, Xudong precision casting factory has changed all of them into aluminum alloy mold or resin mold with high dimensional accuracy and long service life, except for the single sand mold. Although the price has increased, it is still much cheaper than the mold used in metal mold casting. In small batch and large-scale production, the price advantage is particularly prominent. In addition, the fire resistance of sand mold is higher than that of metal mold, so the materials with higher melting point, such as copper alloy and ferrous metal, also use this process. However, there are some disadvantages of sand casting: because each sand casting can only be poured once, the mold is damaged after the casting is obtained, and must be reshaped, so the production efficiency of sand casting is low; and because the overall property of sand is soft and porous, the size accuracy of sand casting is low, and the surface is rough. However, with years of technology accumulation, Xudong precision casting plant has greatly improved the surface condition of sand castings, and its effect after shot blasting is comparable to that of metal castings.