Refractory for induction furnace

Induction furnace structure is shown in the figure. When the induction coil is energized, it generates a large electromagnetic field, and the induction coil generates a large eddy current in the raw material, causing the raw material to heat up, heat up and melt. The raw material is smelted into steel of the required composition and quality by adding ferrous alloys and other metallurgical auxiliary materials, and cast into castings.

Generally induction furnace is relatively small, mainly used for smelting casting and some precision casting steel. In recent years, it is also useful to smelting stainless steel, it is relatively simple refractory, generally knotted material. The induction furnace for melting cast iron is usually made of relatively cheap quartz knotting material, with a service life of 20-40 furnaces. When certain precision casting steel smelting, refining temperature is high, smelting condition is also relatively poor, the service life of quartzose knot material drops greatly, already cannot satisfy the use requirement, then with magnesia, alumina magnesia, magnesium chrome knot dry material, also have the use of al-si series ramming material, there are also some induction furnace use ready-made crucible. That is, when the induction furnace is to be opened, the finished crucible is put in the induction furnace, and the gap between the crucible and the induction coil is made solid with dry knotting material. This method is easy to replace and can improve the utilization rate of the equipment. The refractory crucible is generally made of a castable of a chemical composition similar to that of a dry knotting material, hardened and dried. Repair with the same material when erosion is severe in the slag line, etc. The service life of high quality alkaline dry ramming material or corundum spinel ramming material can reach more than 70 furnaces.

The advantages of dry ramming lining are (1) lower cost; (2) It is not easy to crack, and the accident rate of steel seepage and steel leakage is low; (3) The sintering layer is relatively thin and easy to dismantle the furnace; (4) The dry material behind is not sintered, low density, good insulation effect; (5) No water grade, so almost no oven can be used directly, so it is very beneficial to reduce energy consumption and improve efficiency.