The electric furnace has the characteristics of electromagnetic stirring friction in the process of smelting molten iron. The superheating temperature of molten iron is high, the superheating time is long, and there is friction stir of induced current. It is considered that the floating liquid surface and the slag collector should be bonded together for picking out. In this way, the material that can be used as the graphite crystal core during the eutectic crystallization of molten iron is greatly reduced.
Carbon, the main element of cast iron, decreases and increases in burning loss and absorption process during smelting. Because iron droplets absorb carbon atoms of coke in hot coke and molten iron, carbon absorption is greater than loss and increases in the whole smelting process. The iron solution also absorbed some sulfur from the conversation. The carburizer factory pointed out that when the furnace temperature reached about 1320 ℃, the slag on the clean liquid level was sampled and poured into the sample cup of Shanghai “Holly’s” thermal analyzer. Before and after sampling and analysis, the slag at the liquid level shall be cleaned and the furnace charge shall be added back. When the results of the thermal analyzer come out, adjust the carbon and silicon contents in the molten iron.
A spheroidizing agent is pressed in to perform spheroidizing treatment. Because of the melting speed of the cupola, after packaging, ductile iron is cast, and then processed. The ladle is high temperature, and the molten iron ladle is cooled. To reduce the spheroidization treatment, the melt temperature and the electric furnace can be slightly lower, The quality of the spheroidizing treatment (the fusion and absorption of the spheroidizing agent and the pouring temperature) has little effect. The carburizing agent is supplied to the commercial electric furnace to melt the molten iron. The melting time interval of each furnace is about 50-60 minutes, and the interval may be longer. Sometimes the cooling time of the ladle is long. After the low-temperature ladle and the spheroidizing treatment, the temperature of the molten iron in the bag is about 80 ° C, and the temperature drop may be more in winter. Therefore, when the electric furnace is used to melt the molten iron balls, the melt temperature is higher than the dome of the temperature.