News Stories
Red-hot Ice
29 June 2009 08:38
The doubters on YouTube are wrong! The TRUMPF Red Hot Ice footage is no trick. It’s a bone fide demonstration of induction heating. It shows how a TRUMPF Huettinger power supply and inductor can heat a sliver of metal inside an ice cube without touching or indeed altering the surface temperature. Although not a real life application, this capability demonstrates this technology’s suitability for applications such as shrink fitting a rotor to a crankshaft.
Induction heating works through electro-magnetic fields of specific frequencies. The TRUMPF Huettinger generator produces the high power required to generate the electric fields reliably and stably over many years. The application specific inductor then transfers the generated power into the workpiece. The electromagnetic fields create electric currents in the material and, in combination with its electric resistance, heat up the material just like the filament of a light bulb.
The better the inductor is adapted to the workpiece geometry and the generator, the more efficiently it transfers the energy into the workpiece and this is TRUMPF Huettinger’s proven expertise. By adjusting the frequency the user can determine how deep the energy penetrates the workpiece. Low frequency, as demonstrated by the ice cube, penetrates deep into the workpiece and heats it inside.
High frequencies only heat the surface of the workpiece. If the hot surface is quickly cooled it will become harder but the core of the material remains elastic and therefore break resistant. Intelligent control technology and optimised components assure precise and repeatable results.
In addition to surface hardening, induction is now the heating method of choice for brazing, welding, sealing, melting, epitaxy and crystal growth.
The standard TRUMPF Huettinger TruHeat range of induction heating generators comes in a range of powers. The You Tube example – search on Red Hot Ice – generates 10kW but models in the range are up to 500kW.