Model HL7-M24 General-Purpose Box Furnace

Lucifer Furnaces has delivered a general-purpose box furnace to a manufacturer of precision metal stampings. Model HL7-M24 has chamber dimensions of 12”H x 18”W x 24”D and heats to 2,300° F.

Powered at 15kW, heat is supplied through easy-to-replace coil wired heavy duty heating elements in V-grooved radiant panels on sides, back and door of the furnace. Insulation includes 5” of hot faced insulating firebrick with cold faced mineral wool block behind. 

The roof is lined with ceramic fiberboard to eliminate cracking potential. A 1”-thick cast hearth plate protects floor insulation and provides a flat work surface. This furnace was customized with an air operated vertical lift door activated via foot treadle enabling the door to raise to any height. 

Safety features include a microswitch to auto-disengage power to heating elements when door is opened.  Temperature is controlled with a Honeywell digital time proportioning temperature controller supplemented with an overtemp controller to guard against high limit excursions.  

Other special features include three timers: a soak timer for regular timing functions, an input timer for lower-temp operation and a 7-day timer for auto furnace start up/shutdown. The furnace will be used to heat treat D2 and A2 steel under air atmosphere. This furnace is part of Lucifer’s standard, general-purpose, Series 7000 box furnace lines.