Materials Testing
    Tempering FurnaceTempering Furnace

Tempering Furnace

  • Grieve - TF-183618, TF-243624, TF-304830, TF-364836 and more
  • LED pilot lights
  • On-off heat switch
  • 5 kA short circuit current rating (SCCR)

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Why buy from Geneq? - find out more

These furnaces are used for a variety of heat treating applications including those requiring inert atmospheres.

Recirculating blower provides high velocity vertical down air flow for excellent heat transfer. Precision microprocessor based temperature controls and energy-saving insulation maximize the performance of these rugged units.

Outside Dimensions

  • All Models:
  • Control panel overhang 9″ right side
  • Blower motor overhang 18″ rear except 20″ on 15 HP
  • Gas Models:
  • Burner overhang 18″ right side
  • 325 CFM exhauster to 510,000 BTU/HR, 650 CFM above

Operating Characteristics

  • Accuracy as percent of controller span
  • Uniformity at 100°F below maximum temperature
  • Rise Time in minutes to 100°F below maximum temperature
  • Tests run with empty oven and minimum exhaust
  • Performance will vary with load and application


  • UL Listed Control Panel
  • Meets the Requirements of the Following Standards:
  • NFPA 86 (Standard for Ovens and Furnaces)
  • NFPA 70 (National Electric Code)
  • FM (Factory Mutual)
  • OSHA


  • When processing combustible material fire protection should be considered
  • Not for use with flammable solvents or vapors. Other models available for these applications

Safety Equipment

  • Adjustable manual reset excess temperature interlock to turn off heat on malfunction of main temperature controller
  • Recirculating blower air flow safety switch to turn off heat on loss of recirculated air flow

Electric Heat Includes

  • Separate heating element control contactors to turn off heat on malfunction of main control contactors

Gas Heat Includes

  • Automatic pre-ignition purge period to clear accumulated gas or fumes
  • Push button electric ignition
  • Microprocessor based electronic flame safeguard protection to continuously monitor flame and close gas valves if flame is not present
  • 325 CFM (650 CFM at 510,000 BTU/hr input) stainless steel powered forced exhauster to provide combustion venting
  • Exhauster air flow safety switch to close gas valves on loss of venting
  • Two pilot valves to guarantee gas flow to pilot can be stopped
  • High and Low gas pressure switches to confirm safe operating pressure range
  • Two main burner safety shut off valves with valve seat position indicator to assure gas flow to main burner can be stopped
  • Proof of closure switch on one main valve to prevent igniting pilot unless main valve is closed
  • Leak test station at each pilot and main burner valve to allow testing for leakage through valve
  • Door interlock drives main burners to low fire as door is opened to protect operator from flames


  • Choice of

* Air or Inert Atmosphere construction

* Electric or Gas heat (Air construction only)

* 208 volt, 230 volt or 460 volt, 3-phase, 60 HZ – other input power available

  • All welded construction
  • High temperature alloy coiled wire heating elements supported in alloy rack
  • Modulating burner for 1000 BTU per cubic foot natural gas at 2 psig pressure – propane available – propane available. Inlet 1” NPT
  • Heat source located in heat chamber to prevent radiant heating
  • High pressure, air cooled, stainless steel recirculating blower
  • Full coverage supply and return duct work with adjustable opposed louvers
  • Adjustable fresh air intake and 4” diameter (6” on Gas Heat) exhaust outlet damper
  • 16 gauge 304 stainless steel work space interior
  • Refractory fiber and fire brick heat chamber
  • Insulated with 2” of rockwool and 5”of light weight, energy saving refractory ceramic fiber
  • Load supporting floor insulated with 2” of 18-½ lbs per cubic foot density 1900⁰F block and 4-½” of firebrick,
  • 3/16” steel plate reinforced furnace shell with Trilite Green enamel finish
  • ½” thick steel front plate around door
  • Fire brick throat and doorsill to protect furnace during loading
  • Brushed stainless steel control panel face
  • Powered vertical lift door
  • o Electric door: Electromechanical operator pivots door, supported by structural steel arms and bearings, upward above furnace
  • o Air door: Air cylinder lifts door hanging from heavy duty roller chain supported by sprockets, shaft and pillow block bearings
  • Door hot side faces away from operator
  • Soft insulation on door hot face seals against throat brick and steel front plate
  • Stainless steel grate at bottom of work space for loading
  • Fully assembled and factory tested


Standard & custom-made Grieve ovens in action

*** Not for use with flammable solvents, vapors, or gases ***

TF-18361818" x 36" x 18"6.835" x 87" x 74"1,400°F30190,0007"± 0.3%±12°F958578"4003,100 lbs
TF-24362424" x 36" x 24"1247" x 92" x 80"1,400°F42285,0007"± 0.3%±14°F958590"6004,000 lbs
TF-30483030" x 48" x 30"2553" x 106" x 86"1,400°F52355,0007"± 0.3%±14°F9080102"9005,200 lbs
TF-36483636" x 48" x 36"3659" x 111" x 126"1,400°F65450,0007"± 0.3%±20°F9080126"11006,400 lbs
TF-36603636" x 60" x 36"4559" x 121" x 126"1,400°F74510,0007"± 0.3%±20°F9080126"13006,800 lbs
TF-48484848" x 48" x 48"6471" x 114" x 150"1,400°F100660,0007"± 0.3%±22°F8070150"15008,700 lbs
TF-48724848" x 72" x 48"9671" x 152" x 150"1,400°F120800,0007"± 0.3%±22°F8070150"22009,950 lbs