The Formula for Induction Furnace Charge
The reasonable induction furnace formula for the induction furnace charge can avoid delaying the smelting time due to the adjustment of the composition, prevent the molten steel from being scrapped due to unqualified composition, and increase material consumption and power consumption.
The basic requirements of the induction furnace formula for the charge for the ingredients:
- Accurate batching: Inaccurate batching weight may easily lead to improper control of chemical composition in the smelting process or insufficient pouring of castings, or excessive consumption may occur. The inaccurate distribution of the chemical composition of the charge will bring difficulties to the smelting operation, and in severe cases, the smelting will not be able to proceed. Generally, the batching is carried out according to the smelted steel type, equipment conditions, existing raw materials, and different smelting methods.
The accuracy of the induction furnace batching includes two aspects: the weight of the furnace charge and the composition of the batching. Taking oxidation smelting as an example, if the carbon content is too high, it will increase the ore consumption or prolong the oxygen use time; if the carbon content is too low, it will inevitably increase carbon after melting; The pre-operation brings great difficulties, which not only prolongs the smelting time, but also seriously corrodes the furnace lining, and sometimes even terminates the smelting. In order to prevent the above situation, it is very necessary to master the chemical composition of the steel material and ferroalloy before batching.
- Principles for the use of steel materials for induction furnaces: The principles for the use of steel materials mainly consider the charging method, smelting method, chemical composition of steel grades, and product quality requirements. In addition, when batching, the lumpiness and unit volume weight of steel should also be mastered in advance. Generally, 30-40% of large-block materials, 40-50% of medium-block materials, and 15-25% of small-block materials or light and thin materials should be added to the furnace charge.
Formula ingredient calculation formula for induction furnace charge:
- Batching amount = loaded amount – the total amount of ferroalloy – the amount of iron ore input – the amount of remaining steel returned to the furnace;
- Loading amount = tapping amount/comprehensive steel yield;
- Iron ore input amount = iron ore input amount × iron content × iron income rate. The amount of ore added is generally calculated according to 4% of the tapping amount, the iron content of the ore is 55%, the iron recovery rate is recovered at 80%, and the total comprehensive recovery rate of the charge fluctuates between 92~96%, generally calculated at 94%.
The formula of the induction furnace charge must be properly classified according to the chemical composition, impurity content, and block size. When cutting large and long steel scrap, it is possible to deal with light and thin materials in packaging to ensure smooth feeding and reduce melting time.
The size of the induction furnace charge block size should be adapted to the power frequency, and the power frequency used in the induction furnace decreases with the increase of the furnace capacity. Therefore, large-capacity intermediate frequency furnaces can use large pieces of charge, and small-capacity induction furnaces can use small pieces of charge.