在分析铸件砂型铸造质量缺陷形成机理的基础上，对生产工艺进行改进即采用砂

On the basis of analysis of the casting sand casting defect formation mechanisms on the quality, i.e., improvement of the production process using sand - type compound metal production process. Practice has proved that improved technology significantly improves the quality defects, access to qualified cast, but the rate of qualified products and production efficiency have been greatly improved.

On the basis of analyzing the formation mechanism of casting quality defects in castings, the production process is improved, i.e. the mould-metal combination process is used for production. The production practice proves that the improved process has obviously improved the quality defect, obtained the qualified casting, and greatly improved the product pass rate and production efficiency.

Based on the analysis of the formation mechanism of quality defects in sand casting, the production process is improved, that is, the combination process of sand mold and metal mold is used for production. The production practice shows that the improved process can obviously improve the quality defects, obtain qualified castings, and greatly improve the product qualification rate and production efficiency.<BR>