1. The technology of increasing carbon content in molten iron, especially in electric furnace melting, can increase graphite crystal nuclei. The addition of silicon carbide in cupola melting can also increase the long-term graphite nucleation and distribution of graphite in molten iron, while reducing the oxidation of molten iron;
2. Carbonization is a good measure to prevent or reduce shrinkage tendency. Due to the graphitization expansion effect during the solidification process of molten iron, a good graphitization will reduce the tendency of molten iron to shrink;
3. Under high carbon content conditions, in order to obtain high-strength gray cast iron castings, the melting process adopts the process of adding all scrap steel and graphitized carburetor, making the molten iron cleaner. Melting should use clean materials without oil stains to avoid the occurrence of electric leakage or excessive scum.