Production practice of no-retractor riser in nodular cast iron gear castings

This paper introduces the production experience of the production of medium and large ductile iron gear parts without shrinkage riser. It uses external cooling iron for rain gate, tooth surface and shaft hole thick part. Special alloy is added during spheroidization to ensure tensile strength. . More than one year of production practice shows that the production rate of molten iron process is 97%, and the product qualification rate is over 98%.