Intermediate frequency furnace has more advantages than frequency induction furnace. It is suitable for melting all kinds of cast iron, especially alloy cast iron and nodular cast iron. In recent years, it has been widely used in cast iron production. The furnace has the advantages of high productivity, energy saving and large production flexibility, which is very beneficial to the machine repair plants of industries such as iron and steel metallurgical enterprises and other small batch production of single piece. It has high degree of automation and is equipped with dual power supply and control system. It also has the functions of melting and heat preservation. It is also suitable for continuous operation such as cast iron pipe production, and its application prospect is bound to be promising.

Development of medium frequency electric furnace. At present, the development of power frequency induction furnace to large capacity has basically stopped, while the development of medium frequency induction furnace is remarkable.

1. Static transducer

The development of medium frequency induction furnace benefits from the use of static frequency converter. Compared with magnetic frequency converter, the efficiency of this frequency converter is as high as 95% ～ 98%.

The melting rate of induction furnace changes with the change of furnace capacity. The melting rate of medium frequency furnace is much higher than that of power frequency induction furnace. Replacing power frequency furnace with medium frequency furnace not only reduces land use, but also reduces investment, and ensures continuous supply of molten iron. It is very beneficial for continuous operation and large production capacity of cast iron. The electric efficiency and thermal efficiency of medium frequency induction furnace are high, which not only improves the melting rate and shortens the melting time, but also reduces the unit power consumption.

2. Production flexibility

The medium frequency induction furnace has great flexibility in production arrangement and melting operation.

3. Furnace structure

With the continuous improvement of power density of medium frequency induction furnace, the requirements for safe operation of furnace, improvement of lining life and reduction of noise become higher and higher, and the rationality of furnace structure becomes more and more important. Among them, heavy steel shell furnace has many advantages, such as strong durability, high efficiency, high productivity, low noise and easy maintenance. Reasonable furnace structure is very important, heavy steel shell furnace is only one of them. Many manufacturers are committed to improving the furnace structure to adapt to the application and development of medium frequency induction furnace.

4. Slag removal and furnace repair

The productivity of medium frequency induction furnace is high, and the melting period can be shortened to about 35 min. in order to maximize the power of the furnace, the slag must be removed as soon as possible. In order to solve this very time-consuming and heavy work, there is a method of slag dumping from the back of the furnace, that is, pouring the slag into the transport vehicle through the slot on the back of the furnace top. This method is fast and convenient. The furnace back tilt angle is generally 20 & deg; ~ 25 & deg;.

The intermediate frequency induction furnace must be dismantled and repaired after one furnace service. In order to shorten the shutdown time of replacing refractory lining, mechanization must be considered. Vibration furnace building and lining pusher have become the main parts of large induction furnace. The lining pusher can push out the refractory lining before it is completely cooled, which further shortens the furnace repair time and improves the working environment.

5. Dual power supply and control system

A unique development of medium frequency induction furnace is to use a set of power supply system to supply power to two furnaces, realizing the working system of no production interval operation.

It should be mentioned that the medium frequency induction furnace equipped with dual power supply and control system can ensure the normal production of the other furnace even when one furnace is drying, so as to realize the timely and continuous supply of molten iron, which is unmatched by the power frequency induction furnace.

6. Degree of automation

The medium frequency induction furnace adopts computer control system with high degree of automation. For the high-power medium frequency induction furnace, the melting period is very short and the overheat rate is very high. Only by using the computer control system can the potential of the equipment be brought into play and the most effective protection be provided for the factory and operators. If the furnace with 25-30 ℃ / min superheating and melting charge is unattended for a few minutes at full power, it may cause catastrophic accident. At present, the large medium frequency induction furnace has been equipped with a relatively complete computer-aided monitoring and control system

(1) When the molten iron in the crucible reaches the pre programmed temperature, the power of the furnace can be reduced automatically;

(2) The furnace is fixed on the weight meter, which provides the quality data of the metal charge in the furnace for the computer;

(3) Monitor, calculate and control the temperature of molten iron;

(4) Provide automatic sintering program for new lining;

(5) Determine the amount of carbon, silicon and other added elements needed to achieve the required composition of molten iron;

(6) Other useful and necessary functions including an automatic cold start device.

Yiphee Electric Furnace Co.,Ltd specializes in producing induction furnace.Tel(WhatsApp):+86-13450756789, yiphee@yiphee.cn