In June 2020, a new foundry plant was set up in Jiahe County, Chenzhou City, Hunan Province. We use to the method of coated sand shell mold casting .After one year’s research and improvement, the production technology is constantly improving. The process of yellow coated sand is more faster in production, more environmental protection than clay sand, more higher product finish, besides there is advantage for the dimensional stability. Currently 90% of the products have been changed to coated sand production. And equipped with coated sand production line, which can control the quality requirements of coated sand, and coated sand buried box casting line, further improve the quality of products. The current technology has surpassed 80% of the peer casting technology. Our goal is not yet complete. We want to make the coated sand process into a product with the same grade as the wax film casting method of precision casting.