Hot-Wall Retort Furnaces up to 1100 /°C

These gas tight retort furnaces are equipped with direct or indirect heating depending on temperature. They are perfectly suited for various heat treatment processes requiring a defined protective or a reaction gas atmosphere with a slight overpressure. These compact models can also be laid out for heat treatment under vacuum up to 600 °C. The furnace chamber consists of a gas tight retort with water cooling around the door to protect the special sealing. With the corresponding safety technology, retort furnaces are also suitable for applications under reaction gases, such as hydrogen or, in combination with the IDB package, for inert debinding or for pyrolysis processes.

Different model versions are available depending on the temperature range: 

Models NRA ../06 with Tmax 600 °C

• Heating elements located inside the retort
• Retort made of 1.4571 (X6CrNiMoTi 17-12-2)
• Air circulation fan  and baffle for directed gas flow
• Insulation made of mineral wool
• Furnace temperature control with measurement inside the retort

Models NRA ../09 with Tmax 900 °C

• Design like models NRA ../06 with following differences:
  • Outside heating with heating elements around the retort
  • Retort made of 1.4828 (X15CrNiSi 20-12)
  • Multi-layer refractory insulation and micro-porous panel material
  • Furnace temperature control with measurement outside the retort

Models NR ../11 with Tmax 1100 °C

• Design like models NRA ../09 with following differences:
  • Retort made of 1.4841 (X15CrNiSi 25-21)
  • Without gas-circulation  and baffles
  • Welded support brackets

Standard Equipment

• Compact design with integrated control and gas supply (up to retort furnace NR(A) 700/..)
• Exclusive use of insulation materials without categorization according to EC Regulation No 1272/2008 (CLP). This explicitly means that alumino silicate wool, also known as “refractory ceramic fiber” (RCF), which is classified and possibly carcinogenic, is not used.
• Swivel door hinged on right side
• Open cooling water system
• Control divided into several heating zones
• Temperature uniformity up to +/− 8 °C according to DIN 17052-1 in the empty work space see page 85
• Gas supply system for one non-flammable protective or reaction gas with flow meter and magnetic valve
• Defined application within the constraints of the operating instructions
• NTLog Basic for Nabertherm controller: recording of process data with USB-flash drive
• Controller P570

• Upgrade for other non-flammable gases
• Mass flow controller MFC
• Process controls H3700, H1700 (PLC) including remote maintenance module
• Temperature control as charge control with temperature measurement inside and outside the retort
• Indirect and/or direct cooling
• Heat exchanger with closed-loop cooling water circuit for door cooling
• Oxygen sensor and dew point sensor
• Parallel swing door or electric bayonet catch
• Retort, made of 2.4633 for Tmax 1150 °C
• External switchgear with or without cabinet cooling
• Charge support or custom-built charging trolley
• Temperature uniformity optimized according to DIN 17052 or AMS2750G to +/− 5 °C in empty work space
• Process control and documentation via VCD software package or Nabertherm Control Center (NCC) for monitoring, documentation and control

• Upgrade for other non-flammable gases
• Mass flow controller MFC
• Process controls H3700, H1700 (PLC) including remote maintenance module
• Temperature control as charge control with temperature measurement inside and outside the retort
• Indirect and/or direct cooling
• Heat exchanger with closed-loop cooling water circuit for door cooling
• Oxygen sensor and dew point sensor
• Parallel swing door or electric bayonet catch
• Retort, made of 2.4633 for Tmax 1150 °C
• External switchgear with or without cabinet cooling
• Charge support or custom-built charging trolley
• Temperature uniformity optimized according to DIN 17052 or AMS2750G to +/− 5 °C in empty work space
• Process control and documentation via VCD software package or Nabertherm Control Center (NCC) for monitoring, documentation and control