Series HS3 - High Speed Steel Box Furnaces


HS3 Series Box furnaces for hardening and pre-heating high speed steels and firing ceramics to 2450°F. Control package includes an SCR power supply, digital temperature controller and platinum thermocouple. The SCR proportions the lowest power input required for each application, limiting amperage. Combined with silicon carbide heating elements designed with a 200% aging factor, this unique operating system saves money by providing excellent element life. In addition, initial purchase costs are lowered by eliminating the large expensive power transformer and oversized contactors. Operation is simplified without the manual adjustment required with tap switches.

Designed with silicon carbide heating elements mounted above and below the hearth and low mass ceramic fiber insulation for fast uniform heat. This energy efficient furnace promotes reduced power demand, quicker recovery rates, and lower utility costs.

All models are completely wired, assembled, test fired and shipped ready for connection to 230 single or 3 phase voltage supply. Compact design, fast installation, and simple, safe, dependable operation. Available in five standard sizes.

Standard Features

  • Welded sheet metal shell construction with structural reinforcement.
  • Silicon carbide elements mounted above and below the hearth to provide uniform temperature.
  • SCR power supply.
  • Multi-layered 6" of energy efficient ceramic fiber and mineral wool block insulation for maximum heat storage, minimum heat loss and lower utility costs.
  • Silicon carbide hearth plates support the work load and readily transfer heat from the floor elements.
  • Double-Pivot horizontal swing door keeps hot face surface away from operator.
  • Safety micro-switch shuts off power to elements when door opens.
  • Honeywell digital temperature controller with type R thermocouple.
  • Controls mounted below furnace in enclosed cabinet operate on 230 volts.


Program controls, over temperature safety system, timers, recorders, quench tanks, computer interface, gloves, tongs and foil wrap.


Model Chamber Overall KW Voltage Weight (lbs)
H" W" L" H" W" L"
HS3-K12 12 12 12 66 41 27 8.6 230/1 585
HS3-K18 12 12 18 66 41 33 11.8 230/1 670
HS3-K24 12 12 24 66 41 39 15.5 230/3 755
HS3-M18 12 18 18 66 47 33 16.6 230/3 770
HS3-M24 12 18 24 66 47 39 18.5 230/3 865