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 either a chemical barrier coating on an outer metallic sheath or a ceramic sheath. These designs allows for excellent heat transfer of a metallic substance, while guarding against chemical reaction. Watt densities of 65-150w/in² are possible across a range of heated lengths and radii. 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. 2” and 4” radii with a variety of heated lengths are currently available; larger diameter/higher power heaters are under development.