Sand casting is a traditional casting process that takes sand as the main molding material to make mold.
Gravity casting process is mainly adopted:
Gravity casting refers to the process of injecting molten metal into the mold under the action of the earth’s gravity, also known as casting. Gravity casting in a broad sense includes sand casting, metal casting, investment casting, mud casting, etc; Gravity casting in narrow sense refers to metal mold casting.
Gravity casting is generally adopted for sand mold, and low-pressure casting, centrifugal casting and other processes can also be adopted when there are special requirements. Sand casting has a wide range of adaptability, including small and large parts, simple and complex parts, single parts and large quantities.
The mold used for sand casting was usually made of wood, which is commonly known as wood mold. The disadvantage of wood formwork is that it is easy to deform and damage; In addition to the sand castings produced by a single piece, aluminum alloy molds or resin molds with high dimensional accuracy and long service life can be used. Although the price has increased, it is still much cheaper than the mold used for metal mold casting. The price advantage is particularly prominent in small batch and large-scale production. In addition, sand mold has higher fire resistance than metal mold, so this process is also used for materials with high melting point, such as copper alloy and ferrous metal. However, sand casting also has some shortcomings: because each sand mold can only be poured once, the mold is damaged after obtaining the casting and must be reshaped, so the production efficiency of sand casting is low; Because the overall nature of sand is soft and porous, the dimensional accuracy of sand casting is low and the surface is rough.