••• Advanced Heating
Apogee’s patented, high watt-density, direct-immersion heaters operate submerged in molten aluminum. As the key enabler of Isothermal Melting, Apogee’s design uses a highly conductive material inside the heater, and a chemical barrier coating on an outer metallic sheath. This design allows for excellent heat transfer of a metallic substance, while guarding against chemical reaction. Watt densities of 80-150w/in² are possible across a range of heated lengths and radiuses. Because electrical resistance enjoys 97% conversion to conductive heat energy, Apogee direct immersion heaters operate at less than a 400° F temperature differential between internal heater core and bulk aluminum melt.
Apogee direct immersion heaters, as part of the Isothermal Melting Process, are typically operated as an array of sequential heaters within a separate heating chamber of the ITM furnace. The array is an exceptionally responsive, low-inertia system. During holding periods, direct immersion heaters in an ITM are not energized. When solid aluminum charge is added to the melter’s charge bay, the thermal burden immediately depresses metal temperature. In response, power is automatically supplied to the DI array to offset this loss. Only enough heat to offset the melting burden is necessary, and so only this amount of heat is applied.
Apogee Direct Immersion Heaters are highly customizable. A range of 1 ½ , 2, and even 3’’ radii and variety of heated lengths are available.
Direct Immersion heaters can be used in a range of applications that are not constrained to full Isothermal Melting Systems. Some applications include:
- Supplemental heat for existing gas-reverb furnaces with sidebays
- Temperature manipulation at trough and caster interface
- Prevention of freeze-up in holding vessels such as ladles or induction furnaces
- Emergency heating