Products- Details

Innovation and continuous improvement is our mission. To provide our customers with the best applicable solution is our goal.


FDHK-model (1500 - 5000 mm)

tmax up to 1800 °C

Rotary tube furnace/kiln, rotary drum furnace/kiln, gastight, Ø100 – 1800 mm, heated length 1500 – 5000 mm, Tmax 1800 °C.


ashing, calcination, drying, heat treatment, oxydation, pyrolysis, reduction, thermal recycling

The most important characteristics

  • Thermal treatment of bulk materials (powder, granules, fiber, waste)
  • Resistance heated with FeCrAl-, APM-, MoSi2-heating elements
  • Induction-heated
  • Microwave-heated
  • Hybrid heating (microwave/ resistance heating, resistance/ hot air)
  • Max. operating temperatures up to 1800 °C
  • Insulation of qualitatively superior ceramic fiber
  • High energy efficiency
  • Adjustable inclination and speed
  • Large span of options for customer-specific adaptions
  • Quality made in Germany
  • Easy operation and handling
  • Continous or/ and batch operation 

We make it possible

Linn High Therm is specialized in adapting its products to customer’s requirements. Please let us know if you need any modifications apart from our standard offer. We will do everything to satisfy your wishes. 

Standard options

  • Different temperature controllers
  • Gassing for safe operation when using flammable and explosive gases
  • Burning-off device with flame supervision for safe operation when using flammable and explosive gases
  • Safety package for safe operation
  • Gas warning system for safe operation when using flammable and explosive gases
  • Viewing glass for visual process control or additional pyrometer measuring
  • Condensate trap
  • Process guiding software for full control and documentation via PC  

Further options

  • Up to 10 or more heating zones for best temperature distribution
  • Trailing thermocouple(s)
  • Foldable for easy tube change
  • End caps of stainless steel or alumina or quartz glass for high-purity processes
  • Conveyor system (screw conveyor, vibration or belt conveyor, cellular wheel sluice, double sluice)
  • Feed tank
  • Collecting vessel
  • Inlet and outlet head
  • Gas feeding device for one or more process gases
  • Automatization or integration in manufacturing process chain
  • Dust collector (cyclone, dust filter)
  • Gas/ air pre-heater
  • Thermal afterburning
  • Fittings in rotary tube for improvement of flowing qualities
  • Emergency drive
  • UPS
  • Current measuring
  • Cooling water-heat exchanger
  • Different drum and rotary tube designs are possible 

Product Specifications

Technical data

Furnace housing

The furnace housing is mounted on a tilting frame and fixed on an underframe. The furnace inclination can be adjusted with a manual/ mechanical/ hydraulic lifting device.

The rotary tube drive is done via a frequency-controlled three-phase motor. The lead time can be varied steplessly via speed and work angle of the rotary tube.


The insulation mainly consists of energy saving ceramic fiber material and is designed, depending on application, for cyclic or continuous operation.

Insert tube

Depending on temperature and firing good, different materials for the rotary tube can be used: 

  • Metallic tubes up to 1250 °C
  • Ceramic tubes up to 1800 °C
  • Quartz glass tubes up to 1050 °C
  • Special materials for special applications (acid-resistant stainless steels, Mo, W)

In the insert tube different fittings for improvement of mixing, for prevention of caking, for avoidance of lump formation etc. can be realized. 

Rotary tubes can also be realized as cooling tracks with indirect water cooling.

Gastight design

The gas flows in the rotary tube can be realized in direct current as well as in countercurrent.

Switch and control unit 

  • Safety controller for each heating zone for protection of heating and insulation
  • 3-phase thyristor unit for power regulation
  • Pre-transformer (if necessary)
  • Operating hours counter
  • PLC (e. g. Stange, Simatic, optional possible among others) 

Product properties

Product Line: type series
Operation Mode: Batch and Continuous
Construction Types: Dryer, Furnace
Designs: Rotary tube furnace
Temperature Max (°C): 1800
Heatings: electrical
Heatingmethods: hybrid, induction, microwave/dielectric, resistance
Atmospheres: Air, Controlled gas atmosphere, Vacuum
Applications: ashing, calcination, drying, heat treatment, oxydation, pyrolysis, reduction, thermal recycling