Sand mould casting is a foundry technology that using the sand as the material of the mould to make the mould , and usually sand casting use gravity casting ,and sometimes if have special requirements also adopt low pressue casting , centrifugal casting ,ect. Sand casting have a wide flexibility ,produce of small size parts ,large size parts ,simple one.complex one ,singleton,mass can all adopt. Sand casting ,previously sand casting use the wooden mould ,now use the aluminum alloy mould or resin mould ,the cost of aluminum alloy mould and resin mold are high than wooden mold ,but in the basss produce ,the advantage of cost stand out . sand mold has a better refractoness than metal mould . so cooper alloy and ferrous metal which metting point is high usually use this type technology, but sand casting has the shortage ,because the mould can use only once .,after casting ,the mould is damaged .and need remake the new mould .the production efficiency is low , also the bulk property of sand...