Effect of Hot Metal Charging Technology on Operation of 50 t EAF

The development and application of hot metal charging on 50 t EAF special steel plant at Laiwu Iron and Steel Co., Ltd. is described. The optimal hot metal charging ratio obtained is 30% for gear steel as representative of low carbon steels and 40% for bearing steel as representative of high carbon steels. By system optimization of hot metal charging technology, the production rhythm between EAF and CCM was realized, and productivity was improved. The tap to tap time was shortened by 5-10 min, power consumption was reduced by 80-110 kW·h/t, temperature loss and overheat of molten steel in tundish was reduced by 15-25 ℃. Moreover, the content of tramp elements in EAF bath was effectively diluted, heat number of sequence casting was increased to 162, and operation of EAF and CCM was balanced.