Casting Standard: GB9434-88; flat Standard: JB/T7974-1999; Tolerance: GB6414-1999; Quality tolerances: GB/T11351-89; castings and flat tops hardness HB160-220, flat feet and other products for the HB170- 240 (hardness difference of not more than HB40). Casting annealed to relieve stress ,530-560-degree oven cold. Technical inspection; 1, casting blank may not have trachoma, shrinkage, cracks and other casting defects. 2, the casting to be annealed. 3, casting to clean up. 4, the casting surface to spray anti-rust paint (optional). 5, no injection molding fillet radius R10. Casting method is commonly used in sand casting, followed by special casting methods, such as: metal casting, investment casting, plaster casting ...... and so on. The sand casting sand can be divided into clay, organic binder sand, resin self-hardening sand, lost foam, and so on. Casting method selected principles: 1 priority use sand casting, sand casting is mainly due to lower cost than other casting methods, production process is simple, short production cycle. When the wet type can not meet the requirements and then consider the use of clay, sand is dry sand, dry sand or other sand. Clay wet weight of the casting sand casting from a few kilograms up to tens of kilograms, while the production of dry clay castings can weigh tens of tons. 2 casting and production volume should be adapted. Low pressure die casting, die casting, centrifugal casting and other casting methods, because of equipment and tooling is expensive, so only suitable for mass production. 3 modeling method should be suitable for factory conditions. For example, as is the production of large castings such as machine bed, the general set of core modeling method does not create the appearance and sand box, to pit groups in the core; and other factory sand box modeling method is used, making the appearance. Different production conditions (including equipment, facilities, staff quality, etc.), production practices, the experience not the same, should be based on what these conditions are considered suitable for the product and not suitable (or not) what the product. 4 to take into account the cost of the casting accuracy and