Sheet small batch production of heavy castings, manual modeling is still the important method, manual can meet the requirements of various complex is more flexible, does not require a lot of process equipment.Can be used sodium silicate sand, sodium silicate sand mold VRH law, organic ester sodium silicate self-hardening sand, clay self-hardening sand mould and dry type, resin cement sand mold, etc.;Made for single piece of heavy castings, pit modelling method of low cost, fast production.Batch production or long-term production of finalize the design product box, split box shape modelling method is appropriate, although high mould and sand box to start investing, but from compensated save modelling cycle time, improve the quality of its products.Casting methods, such as low pressure casting, die casting, centrifugal casting, precision casting for equipment and mold is expensive, so only suitable for mass production.