Induction technology is the collective noun for applications in which electric currents are induced by applying a changing magnetic field. Induction technology has many applications, from energy transfer for electrically conductive objects or contactless and wireless charging to measuringdistances and properties of conductive and ferromagnetic objects.
Read more about inductive charging and inductive supplies
More and more often, it is desirable for both industry and consumers to transfer energy without the need for wires or contact. This is among others useful for charging batteries for cars, drones and such, or for powering devices and machines directly. Induction is an excellent way to achieve this.
Read more about inductive measuring
Het principle of induction can be used for all kinds of measurements. For instance, for determining certain properties of an object, or for measuring a distance to a ferromagnetic object. These in itself are powerful applications, however, they can be used to make a machine that uses induction for heating or charging/supplying very intelligent by using the measurements that are basically inherently there. For instance, an induction heating device can take all kinds of measurements on the object it is heating. From the results of these measurements, it can draw conclusions about the dimensions and other properties of the object. It can then adapt the heating procedures accordingly.
Read more about induction heating
Induction heating is a method in which an electrically conductive object is heated with electrical currents that are induced in the object. Induction heating is fast, clean, contactless and uses no flame. The principal is that with one or more coils a changing magnetic field is created. If an electrically conductive object is placed in this magnetic field, as a result of the changing magnetic field, eddy currents will flow in the object.
How deep these eddy currents penetrate the object depends on the frequency of the magnetic field as well as the properties of the material of the object. Thanks to the Ohmic resistance of the material of the object as well as losses due to hysteresis as a result of the switching of the polarity of the magnetic field (in a ferromagnetic object), energy is dissipated in the material and thus heat is created.
A big advance of induction heating is that it is a very well regulated and controllable process with a high yield, that it is safe, clean and quiet, and that it can be applied very locally. Generally, three categories are distinguished, low-, middle-, and high-frequency. These terms are often abbreviated to LF, MF and HF respectively.
The choice of a specific frequency is strongly dependent on the application. An LF-heater, for example, as a result of the great penetration dept of its induced eddy currents, ensures smooth heating and is therefore extremely suitable for the assembly of components. For the disassembly of components, on the other hand, a MF-heater is better suited due to the lesser penetration depth. As a result, a bearing can for example be heated whilst the shaft on which this is mounted remains unheated. Because of this, only the bearing expands and can easily be removed from the shaft.
A HF-verhitter is better suited for heating objects that have less ohmic resistance and/or which are hard to magnetize such as copper and aluminium. For an LF-heater it is often necessary to use a large core in order to create enough flux. The addition of a core is usually not necessary for an MF- or HF-heater, however, for those types of heaters the components are more costly.
Induction heating can be used among others for the assembly and disassembly of crimp joints, such as for example:
- Bearings, gears and flanges, for example in train wheels, boilers or wind mills.
- The removal of attached components (for example nuts) in cars, trucks, cranes or production-installations.
Next to that it is useful for (pre-)heating:
- For the welding, soldering or hardening of metal surfaces
- For removing layers of paint from metal surfaces. For instance paint from a car, induction heating heats the adhesion surface directly through the layer of paint.
HedoN is an expert in induction technology, our products can be found all over the world. Our technical expertise consists of deep knowledge of contactless energy transfer by using of a magnetic field. We also have extensive knowledge of the associated control principles and systems as well as the required electronics.
HedoN has been developing products for induction heating for renowned customers since 1990. Please visit the links underneath for a few examples of the products that HedoN has developed. Feel free to contact us or more information.