Medium frequency induction melting furnace
The medium frequency induction melting furnace adopts the principle of medium frequency electromagnetic heating. It is a non-standard induction heating equipment for heating molten metal. The ultimate purpose of this equipment is to melt metal. It has the characteristics of fast melting speed, convenient variety replacement and ready to use. It has become a standard equipment for metal melting in the casting industry and an indispensable heating equipment in the casting industry.
I Heating principle of medium frequency induction melting furnace:
The medium frequency induction melting furnace is composed of two important parts: the medium frequency power supply and the heating melting coil. The medium frequency power supply first rectifies the three-phase alternating current (with thyristor) into a single-phase direct current, and then inverts it into a 500-10000hz pulse alternating current by the inverter bridge. This strong alternating current is transmitted to the heating melting coil (usually made of red copper tube) through the water-cooled cable. Thus, a strong magnetic beam with instantaneous polarity change is generated in the smelting coil. When the heated object such as metal is placed in the coil, the magnetic beam will pass through the whole heated object, and a corresponding large eddy current will be generated in the direction opposite to the heating current in the interior of the heated object. Because there is resistance in the heated object, it will produce a lot of Joule heat, which will make the temperature of the object rise rapidly. To achieve the purpose of heating and melting all metal materials.
II Composition of medium frequency induction melting furnace:
The medium frequency induction melting furnace is composed of medium frequency power supply, capacitor bank, water-cooled cable, connecting copper bar, inductor coil, movable furnace body, fixed support, yoke, furnace leakage alarm, water temperature alarm, furnace lining material, hydraulic system, furnace tilting console, hydraulic oil cylinder, circulating cooling water, etc.
III Features of medium frequency induction melting furnace:
1. The medium frequency induction melting furnace has a high influence on the power factor of the power grid. The medium frequency power supply is a voltage type series inverter power supply. The rectifier has been working at zero. It does not adjust the rectifier, but only adjusts the inverter. Therefore, the power factor is high, greater than 0.95, and there is no high-order harmonic. In all smelting plants, it always provides substantial benefits to users in energy saving, operation and production. We guarantee that the power factor of the equipment is always greater than 0.95 under any working condition.
2. Medium frequency induction melting furnace saves power consumption. Due to the design of series resonant circuit, the reactive current is small, which greatly reduces the power consumption. 0.5T 300kW medium frequency furnace 1450 degrees of iron melting, 680 degrees of power consumption, 1600 degrees of steel melting, 720 degrees of power consumption. The parallel thyristor 0.5T medium frequency furnace needs to be driven by 500kW transformer, while the series inverter 0.5T medium frequency furnace can work normally as long as 300kW transformer, and the power consumption is very small. The capacity use cost saved by long-term calculation is more than 100000 yuan a year. 3. The medium frequency induction melting furnace always maintains constant power output in the melting process. Compared with the parallel inverter medium frequency power supply, the power regulation mode is different. The parallel medium frequency power supply adjusts the DC voltage, while the product produced by our company adjusts the frequency. It is not affected by the amount of charge and maintains constant power in the whole smelting process. Especially when smelting non-magnetic materials such as stainless steel, copper, industrial silicon and aluminum, it shows its advantages. The melting speed is fast, the burning loss of charge elements is less, the energy-saving effect is better, and the casting cost is reduced.
4. The capacity of power transformer of medium frequency induction melting furnace is small. Taking the half ton furnace as an example, the half ton series medium frequency furnace produced by Luoyang Wanle power equipment factory only needs 300kW, and the low-voltage measuring voltage of the transformer is 380V. In this way, for general foundry enterprises, only one transformer below 315KW can be used, and the power consumption such as lighting, traveling crane and water pump can share one transformer.
5. The medium frequency induction melting furnace has less burning loss of alloy elements; Due to electromagnetic stirring, the composition of molten metal is uniform without segregation; The induction furnace has the advantages of easy melting control, good operating conditions, low environmental pollution and low noise; It is convenient and economical to reuse metal charge (small to iron filings and large to the size of furnace). Therefore, melting cast iron in medium frequency induction melting furnace has been widely used.
6. The medium frequency induction melting furnace adopts sweep frequency zero voltage soft start mode, which can be started or stopped at any time under any state without impact on the power supply; Rapid smelting and low production cost; Low pollution and environmental protection requirements; It is convenient to change all kinds of molten solution directly from the cold furnace;
7. The power regulation of medium frequency induction melting furnace is flexible, convenient and can be adjusted continuously and smoothly; Uniform temperature, easy to control, less oxidation and burning loss, and uniform metal composition; The power supply system has the function of diagnosing errors and is easy to repair.
8. The shell of medium frequency induction melting furnace adopts cast aluminum alloy or steel shell structure, with small floor area; The furnace body is easy to overturn and dump, and electric, manual, hydraulic and other tilting methods can be selected as required.
9. The inverter angle automatic adjustment circuit is designed for the medium frequency induction melting furnace, which can automatically adjust the matching of load impedance to achieve constant power output, and make the equipment run in a good working state without adjusting the compensation capacitance;