Lucifer Furnaces, Warrington, Pa., has shipped a customized benchtop heat-treating furnace to R. Hueter Co., Beverly, Mass., a CNC machine shop, to harden beryllium-copper pins. With a chamber size of 9x12x12 inches, Model 42GT-H12 is insulated with five inches of both insulating firebrick and mineral wool backup. Four kilowatts of power allow fast heat-up to 1200°F.
Hueter plans to use the furnace primarily at around 600°F for two-hour cycles, to achieve a specific Rockwell hardness on small lots of beryllium-copper pins. They will be treated under a nitrogen atmosphere to reduce surface oxidation and achieve a scale-free, bright finish.
The GT ovens, built for operation with an inert atmosphere, are crafted with a continuously welded outer steel shell and gasketed roof plate. A strong seal on the double-pivot door is achieved with a square gasket around the door perimeter to form a tight seal to the oven face-plate. Swing bolts with T handles make clamping easy.
The stainless-steel liner baffles the work chamber from the side wall heating elements, and directs the air flow horizontally through the chamber for uniform heating. Hueter chose a Honeywell DC2500 temperature controller with a soak timer to shut off heating elements at the end of a programmed cycle, in addition to a flowmeter mounted and piped to the oven for easy connection to the atmosphere supply.
