smelting
High temperature and low sulfur pure hot iron is the key to produce high quality ductile iron. Domestic production equipment is mainly cupola, hot metal has not been pre-desulfurization treatment; Next is high pure pig iron is little, coke quality is poor. The cupola is used to melt molten iron, desulphurize outside the furnace, and then heat up in the induction furnace and adjust the composition. The vacuum direct reading spectrometer has been widely used to detect the composition of hot metal in China.
This paper by guilin new ronghuang machinery co., LTD