The charging of the induction furnace is the basis to ensure the smooth melting process. The disassembly of charge causes many problems, such as a prolonged melting period, increased metal loss, and increased power consumption. Therefore, enough attention must be paid to the charging work.
- The bottom slag paved the bottom
After the crucible is cleaned and maintained, the bottom slag should be added. Lime and fluorite slag is added during alkaline crucible smelting. Acid crucible smelting, add broken glass slag. Ensure that the molten steel is covered with slag during the melting period.
The tightness of the charging
Charging requires that the lower part be tight and the upper part loses. That is to say, the bulk density of the middle and lower part of the crucible should be as low as possible to improve heating efficiency (the density of magnetic field lines in the middle and lower part is the highest). The upper packing density is small, which is convenient for the charge to go down smoothly when melting and reduces the probability of forming bridging.
The layered parts of the charging
1.The bottom is the low-temperature area of the crucible, which should be loaded with easy melting charges such as high and middle carbon steel block, high carbon ferroalloy, electrolytic nickel block, ferromanganese, ferrosilicon, copper, manganese metal, etc.
2.The middle part is the crucible high temperature zone, which should be loaded into refractory materials with high melting point and high density, such as Ferro – Tungsten, Ferro – molybdenum, micro – carbon ferrochrome, low – carbon ferrochrome, Ferro – niobium, and metal charges such as tungsten, molybdenum, niobium, chromium, cobalt, etc.
3.The upper part is the low temperature area of the crucible, which should be loaded into steel material, industrial pure iron, etc.
4.Loading of return materials, large heavy materials into the lower part of the crucible, light materials, baling, and packing materials into the upper part.
Burden lumpiness, density, and melting point
The lumpiness of the charge depends on the furnace capacity and power frequency. In principle, a large furnace with low frequency and large capacity can use bulk charge. The furnace with higher frequency and smaller capacity uses smaller material blocks.
Heavy density, high melting point charges, such as ferrotungsten, ferromolybdenum, micro-carbon ferrochrome, etc., must be broken into the smaller material blocks. Heavy density, a low melting point of the burden, allows the use of a larger aniseed block.