Sand casting is a traditional casting process that uses sand as the main molding material to make casting molds. Sand casting generally uses gravity casting. When special requirements are required, low pressure casting, centrifugal casting and other processes can also be used. Sand casting has a wide range of adaptability. Small, large, simple, complex, single and large batches can be used. Sand casting molds were previously made of wood, commonly known as wood molds. In order to change the shortcomings such as easy deformation and damage of wooden molds, Xudong Precision Casting Factory changed all aluminum molds or resin molds with higher dimensional accuracy and longer service life except sand castings produced in one piece. Although the price has increased, it is still much cheaper than the molds used for metal mold casting. In small batches and large parts production, the price advantage is particularly prominent. In addition, sand molds have higher fire resistance than metal molds, so materials with higher melting points such as copper alloys and ferrous metals also use this process. However, sand casting has some disadvantages: because each sand casting can only be poured once, the casting is damaged after obtaining the casting, and it must be reshaped, so the production efficiency of sand casting is low; and because the overall nature of the sand is soft And porous, so sand casting castings have lower dimensional accuracy and rougher surfaces. However, the precision casting factory has accumulated many years of technology accumulation, which has greatly improved the surface condition of sand castings, and its effect after shot blasting can be comparable to metal castings.