Induction furnace: principle of operation and scope

The technology of melting metals by induction heating has evolved over a hundred years, it continues to improve until now. It all started with the discovery of the phenomenon of electromagnetic induction by the scientist M. Faraday . Already at that time the first practical attempts were made to create a new technology for melting metals in the laboratory, but all of them ended in failure. At that time, there were no installations capable of generating high-frequency currents of sufficient power.

The first induction furnace was proposed by S. Farranti in 1887. But until the time of its practical implementation, a lot of time has passed. In 1890, Benedicks Bultfabrik realized this idea, there was a real opportunity on an industrial scale to carry out the smelting of metals using a new technology. But at that time there were no powerful current sources, so the induction furnace worked with insignificant volumes of metal.

The situation began to change at the beginning of the 20th century, when the furnace design underwent significant changes. There were powerful generators and high-frequency current sources , which were used to ensure its operation.

The development of semiconductor devices and the appearance of the first thyristor converters made it possible to create effective feeding systems based on them. A modern induction furnace is able to work with large volumes of metal. Due to the use of innovative management systems, it has become more economical.

This technology makes it possible to obtain ultrapure alloys of various metals. If the traditional melting method, for example, in a converter, leaves a large percentage of impurities, then using this method they are not available. This allows you to create ultra-pure alloys with good performance.

The very principle of operation of the induction furnace, which consists in the non-contact heating of metals by means of an electromagnetic field, is of interest . This happens with the help of an inductor, the load of which is the metal loaded into the furnace. If the capacity of the furnace is high enough, then melting occurs.

The induction furnace itself can have a wide variety of dimensions and purpose. It can be used in laboratory installations or large production complexes, have different power and performance.

A small homemade induction oven may well come in handy in a home laboratory. With its help, you can make, for example, solder with different contents of zinc and tin, and much more. When it is manufactured, the above-described principle of operation must be taken into account. Use a high-frequency generator (from 30 MHz and higher), a powerful power source, power modules, and as a result, in a crucible (it can consist of 6-15 turns of PEV-8.0 wire) it will be possible to melt a piece of zinc in a short time (15 -20 seconds).

The development of this technology follows the path of gradual capacity expansion of facilities, improvement of the elemental power base, increase in the frequency of the generator and the use of innovative developments in control, monitoring and protection schemes.