Lucifer Furnaces Inc. designed and delivered a dual-chamber furnace for heat treating high-speed steels. With inside chamber dimensions of 12 inches high x 12 inches wide x 24 inches long, it will used in a newly built tool room at a large corporation. The furnace heats to 2450°F in the upper chamber with silicon-carbide heating elements mounted across the roof and below the hearth. The lower chamber is a recirculating oven reaching up to 1600°F with a rear-mounted fan directing airflow horizontally through the chamber for temperature uniformity.
Elements are a solid-bar-type with termination connections for easy service via removable covers on both sides of the furnace. The upper chamber is insulated with 6.5 inches of combined ceramic-fiber hot-face and mineral-wool cold-face insulation for lower power demand, with staggered seams to block direct heat flow to minimize outer shell temperature. Lower-chamber insulation consists of multilayered lightweight insulating firebrick hot face and mineral-wool backup, dry fit to allow for thermal expansion. Standard controls include a Honeywell DC2500 time-proportioning controller for each chamber.