Working tubes and reactors

Ceramic working tubes

  • Different qualities of alumina (Al2O3) ceramics for temperatures up to 1800 °C
  • Other ceramics for temperatures up to 2000 °C
  • Nearly any diameter and length available
    (up to 1500 mm)
  • Working tubes consisting of joint segments (for long tube lengths and to compensate temperature gradients),
    with leakage rates
    < 1*10-4 mbar*l/sec
  • Machined tube surfaces and tube ends to attach seals
  • Tubes with one end closed

Working tubes and reactors made of quartz glass

  • Suitable for working temperatures up to 1200 °C
  • Nearly any diameter and length available
    (up to 1500 mm)
  • Fused-on holders for positioning of thermocouples, gas inlet and outlet, vacuum connectors or similar
  • Reactor design according to customer drawings possible.

Working tubes made of high-melting metal alloys

  • Materials: stainless steel, nickel alloys (e.g. inconel or hasteloy)
  • Operation temperatures
    up to 1200 °C

Flanges, inserts and sample holders

Gas-tight flanges and tube plugs

We offer standard and custom-made
gas-tight and vacuum-tight tube flanges and plugs for all usual quartz or ceramic working tubes and reactors – no matter whether it is for a new or an existing heating system.

The materials used for these parts extend from temperature-resistant stainless steel to acid-resistant quartz attachments to HCl-resistant flange systems made of inconel or hasteloy.

Displacers and baffles

For manipulating the flow of gases and materials, we offer various heating space inserts, for example quartz displacers, fillings, honeycombs and frits made of quartz glass or ceramics.

Sample holders

Based on the long-term
co-operation with our customers and
the knowledge of their processes and applications, we have comprehensive experience regarding the optimum positioning or insertion of samples in the heating space.
Please contact us if you need special advice on the design of sample holders for solids, fluids, melts or powdered samples as well as on their optimum positioning in the furnace chamber.

Linings and insulations

High temperature insulation

Our experiences staff will be pleased to give advice on applications and compatibility of refractory and high temperature resistant materials.


As for HTM’s LOSA, LOBA and LORA tube furnace models, the heater support tube itself can be used as working tube when working in air. For applications in defined atmospheres, we offer specific working tubes and reactors made of diverse materials and with nearly any diameter and length that provide the possibility of a hermetically sealed working space.
Furthermore, refractory fillers and linings can provide specific conditions for customer applications.