Induction billet heater for the heating of billets before extruding

The flexibletype of heater is the induction heater. Operating in 'lot size 1' mode, it allows the operator to set any desired temperature profile – the so-called "taper" – over the length of the billet for an isothermal extrusion process. As the induction heater heats every billet individually, billet-to-billet temperature or length variations (in conjunction with a cold saw) can be implemented without impairing the particularly close temperature tolerance. Apart from the custom-designed induction coil, Otto Junker's IGBT frequency converter – built into hundreds of installations and providing numerous parameter variation options (power, frequency) – is at the core of this technology. The system can be supplied with optional equipment such as transformers or water recooling systems.

Where particularly high flexibility standards apply, induction heaters are preferably employed as a "standalone" solution. If the main process objective is to obtain a reproducible taper rather than to maximize flexibility, the induction heater can be used both in parallel and in line with an upstream gas fired heater.

Further unique selling points of the JunkerDynamicHeater^TM billet heaters include the following:

• Ceramic melt protection tube reduces energy demand.
• OTTO JUNKER billet trough conveyor system prevents scratches and scoring on the billet surface and eliminates aluminium build-up in the coil.
• The 'blind heating sequence' increases the thermocouple maintenance interval by a factor of 2.
• IGBT converter and coil, as core components, are built in-house and tested/adjusted before shipment.

The JunkerDynamicHeater^TM – SC is the small-footprint, low-budget solution. This easily retrofittable version of an induction heater is used to boost the output of an existing gas fired heater or to provide a temperature profiling ("taper") capability. It is characterized by its particularly compact design, given that the so called JuDy – SC unit needs only one single short coil section. A special measuring and control process developed by OTTO JUNKER allows the temperature profile to be created dynamically during the passage of the billet.