High-temperature thermocouples with metal and ceramic thermowells
Above about +800 °C it is no longer the thermocouple that decides the service life but the thermowell. Scale, furnace atmosphere and thermal cycling attack it — and when it fails, the measuring insert is lost with it.
That is why our high-temperature sensors are built in two parts: thermowell and measuring insert can be replaced separately. Up to +1,250 °C the metal thermowell of the TSM-1series does the job, above that the gas-tight ceramic tube of the TSK series up to +1,600 °C.
We manufacture in Hanau to your specification — nominal length, material, process connection and connection head freely selectable, also as a rebuild to sample or drawing.
Which series suits your process?
| Use | Typ | Thermowell | Limit |
|---|---|---|---|
| Hardening, annealing and tempering furnaces | TSM-1 | Metal 1.4571 … Kanthal APM | bis +1.250 °C |
| Exhaust gas and afterburner sections | TSM-1 | Metal, ceramic inner tube optional | bis +1.250 °C |
| Melting and holding furnaces, foundry | TSM-1 / TSK | Metal or ceramic | bis +1.250 / +1.600 °C |
| Glass, ceramic and firing processes | TSK | Ceramic C610 / C799, gas-tight | bis +1.600 °C |
Thermocouple type K and N up to +1,200 °C; above that noble metal type S, R or B. With noble-metal thermocouples a ceramic inner tube is standard, because metal vapours poison the wires.
Choose a design and configure it
Two series, each with a dimension drawing, technical data and the order key as a configurator. What decides is the temperature at the tube and the atmosphere it stands in.
Ceramic thermowell
TSK
Gas-tight ceramic tube with a metal support tube — for melts, firing processes and noble-metal thermocouples.
C610 / C799 Ø 10 / 15 / 24 mm · bis +1.600 °C
Thermowell and measuring insert
Metal thermowells
1.4571 withstands up to +800 °C, 1.4841 and 1.4749 up to +1,150 °C, 1.4762 up to +1,200 °C. Kanthal APM reaches +1,250 °C and forms a dense alumina layer that lasts considerably longer in an oxidising furnace atmosphere than chrome-nickel steel.
Ceramic thermowells
C610 is gas-tight and inexpensive, C799 consists of more than 99 % alumina and is standard for noble-metal thermocouples. Both sit in a metal support tube that takes the mechanical load — ceramic breaks when bent.
Measuring insert
Thermocouple wire in ceramic beads is the cheaper solution and the more robust one at very high temperatures, a sheathed thermocouple is faster and less sensitive to vibration. Both can be changed without removing the thermowell.
For temperature profiles over the height of a reactor: Multipoint thermocouples. For the range below +800 °C: Thermowell thermocouples to DIN 43772.
Please contact us
We are glad to help with questions about products, versions and delivery times.
Dennis Kühne
Phone: +49 6181 504 93 18
Mobile: +49 160 91437153
E-mail: info@ghi-gmbh.de
