At present, in the intermediate frequency industry, the intermediate frequency melting furnace structure is divided into a steel shell with a yoke hydraulic tilting furnace and an aluminum shell with a reducer tilting furnace. usually
Steel shell furnace:
Has a long life (generally normal service life is more than 10 years),
The stability is good, because the magnetizer has two functions: first, the top wire of the magnetizer is firmly fixed with the induction coil, so that the coil and the magnetizer form a stable structure. Second, the magnetizer can form a magnetic permeability barrier around the coil;
Energy saving, because the furnace with the magnetizer saves 3%-5% compared with the aluminum shell furnace;
The casting is stable and the hydraulic tilting device can well grasp the casting angle and speed;
The safety performance is good, due to the characteristics of the leaking alarm device and the refractory rubber layer. The good characteristics are selected in the steel shell structure when the tonnage is more than 2T.
Aluminum shell furnace:
Aluminum shell furnace is a simple structure, the service life is generally about 5-8 years, there is no magnetizer, furnace lining mechanism, refractory clay layer, its safety performance is poor, generally used with capacity below 2T. For example: a 5T medium frequency furnace, when the furnace is full of molten iron, the overall weight of the equipment reaches 8-10T. If the aluminum shell structure is selected, when the reducer rotates the furnace body to 95 degrees, the whole furnace body will lean forward, and the safety performance is very good. difference. The aluminum shell furnace is suitable for users who change production in a short time, small tonnage.
The following are the specific advantages and disadvantages of steel shell furnace and aluminum shell furnace.
Compared with the aluminum shell furnace, the advantages of the steel shell furnace are five points:
1) Rugged and elegant, especially for large-capacity furnaces, which require a strong rigid structure. From the safety point of the tilting furnace, try to use steel shell furnace.
2) The yoke made of silicon steel sheet shields and emits magnetic lines generated by the induction coil, reduces magnetic leakage, improves thermal efficiency, increases production, and saves energy by about 5%-8%.
3) The presence of the furnace cover reduces heat loss and increases the safety of the equipment.
4) Long service life, aluminum oxidation is more serious at high temperatures, resulting in metal toughness fatigue. At the foundry company site, it is often seen that the aluminum shell furnace shell used for a year or so is broken, and the steel shell furnace has a much longer leakage life due to less magnetic leakage.
5) Safety performance The steel shell furnace is much better than the aluminum shell furnace. When the aluminum shell furnace is smelted, the aluminum shell is easily deformed due to high temperature and heavy pressure, and the safety is poor. The steel shell furnace uses a hydraulic tilting furnace and is safe and reliable.
According to industry practice, the supply melting furnace of aluminum alloy structure with the reducer as the tilting method is commonly known as the aluminum shell furnace. Induction melting furnaces with steel cylinders in the form of tilting furnaces are commonly known as steel shell furnaces.
