Gu Chang in the production process of ductile iron foundry covers: 1. Shanxi covers the stringent requirements of the chemical composition of plants, carbon and silicon content of the original liquid iron requirements than gray iron, ductile iron to reduce the content of manganese, phosphorus and sulfur. 2. Make the ball handling, which was added to the iron ball agent. 3. Add inoculant were inoculation. 4. The liquid iron baked higher temperatures than gray cast iron, to compensate for the ball, bred loss treatment temperature of molten iron. 5. ductile illiquid, shrink large, and therefore requires a higher temperature and larger casting gating system size, rational application of the riser, chills Shanxi covers wholesale, using the principle of solidification. Gu Chang-year foundry with you to explain what is heat-treated cast iron covers: Heat cast iron covers the use of heating and cooling methods, regularly changing the core body tissue Shanxi cast iron manhole covers ordering, so that it has acquired the appropriate organization performance, to satisfy the conditions required for a particular job, such as high strength, hardness, wear resistance, good summary ductility, toughness and so on. Our Address: Taigu County towns Hu Dong village crossing State Road 108. Shanxi covers manufacturers | Chang in foundry (certified) | Shanxi Taigu covers provided by Chang in foundry. Gu Chang-year foundry (www.sxcnzz.com) is Jinzhong, machining leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Chang-year leadership in the foundry staff warmly welcome all inquiries negotiations to create Chang foundry in a better future.