The reasonable speed of the medium frequency furnace can avoid delaying the melting time due to the adjustment of the composition, eliminate the scrap of the liquid steel due to the unqualified composition, and increase the material consumption and power consumption.

Basic requirements for batching of intermediate frequency furnace in Hubei:

1, accurate ingredients: the weight of the ingredients is not allowed, which can easily lead to improper control of the chemical composition of the smelting process or cause insufficient casting, and may also excessive and increase consumption. Inaccurate distribution of chemical composition of charge will bring difficulties to smelting operation, and will make smelting impossible in serious cases. Generally, it is based on the smelting steel, equipment conditions, existing raw materials and different smelting methods.

The accuracy of the batching includes the weight of the charge and the composition of the batching. Taking oxidation smelting as an example, if the amount of carbon is too high, it will increase the ore consumption or prolong the oxygen use time. The amount of carbon is too low, it is bound to be carburized after melting; If the S and P in the charge are too high, it brings great difficulties to the operation in front of the furnace, not only prolongs the smelting time, but also seriously eroses the furnace lining, and sometimes even terminates the smelting. In order to eliminate the above situation, it is necessary to master the chemical composition of the relevant steel materials and ferroalloys before dosing.

2, the principle of the use of steel materials: the principle of the use of steel materials mainly considers the loading method, smelting method, chemical composition of steel and product quality requirements. In addition, when batching, the block degree and unit volume weight of steel should be mastered in advance. In general, bulk material 30~40%, medium block material 40~50%, small block material or light material 15~25% should be added to the charge.

Hubei intermediate frequency furnace batching charge calculation formula:

1, dosage = loading amount - total amount of ferroalloy - iron ore intake amount - residual steel return amount;

2, loading amount = steel output/steel comprehensive yield;

3, iron ore input = iron ore added amount × iron content × iron income rate. The amount of ore added is generally calculated according to 4% of the steel output, the iron content of the ore is 55%, the iron recovery rate is 80%, and the total comprehensive recovery rate of the charge fluctuates from 92 to 96%, generally calculated according to 94%.

The charge of the intermediate frequency furnace must be properly classified according to the chemical composition, impurity content and block size, cut large and long scrap steel, and should be packaged with light and thin materials to reduce the melting time. The size of the bulk of the charge should be commensurate with the frequency of the power supply, and the frequency of the power supply used in the induction furnace decreases with the increase of the furnace capacity. Therefore, large-capacity medium-frequency furnaces can use large blocks of charge, and small-capacity induction furnaces use small blocks of charge.