Induction furnace steelmaking is put induction furnace raw material like scrap steel waiting to be melted in the furnace. When the induction coil is energized, it generates a large electromagnetic field, and causes the induction furnace raw materials in the furnace to generate a large eddy current, resulting in raw materials heating up and melting.
By adding induction furnace metallurgical auxiliary materials such as ferroalloy, the added raw materials are smelted into steel with the required composition and quality, and then poured into castings in the next step.
Generally, induction furnaces are relatively small and are mainly used for smelting and casting steel for certain precision castings.
In recent years, it has also been used to smelt stainless steel. The refractory materials it uses are relatively simple and are generally knotting materials.
For induction furnaces for melting cast iron, generally cheaper quartz-based binders are used, and the service life is 20-40 furnace times.
When smelting certain precision casting steels, the smelting temperature is high, the smelting conditions are relatively harsh, and the service life of the quartz-based knotting material is greatly reduced, which can no longer meet the use.
At this time, magnesium, aluminum-magnesium, and magnesium-chromium are used. High-quality dry knotting materials and silicon-based knotting materials are also used.
When the erosion of the slag line and other places is serious, repair it with the same material. The service life of high-quality alkaline dry ramming material or corundum spinel ramming material can reach more than 70 furnace times.
There are also some induction furnaces that use ready-made crucibles (prefabricated parts for induction furnace sleeves). That is to say, when the induction furnace is opened, the finished crucible should be placed in the induction furnace, and the gap between the crucible and the induction coil should be compacted with dry knotting material.
This method is easy to replace and can improve the utilization rate of the equipment.
The crucible of this kind of induction furnace refractory is generally prefabricated by pouring refractory castables similar to dry knotting materials, and then hardened and dried.