Gas Turbine Exhaust Thermocouple


Thread Starter


In GE Gas turbine what is the average life of
Exhaust Thermocouple? It is chromel-Alumel thermo
couple.Average temperature is around 500 deg C.

Tom Brickner

I am not sure if there is an easy answer to your question due to the atmosphere and style of thermocouple you are using. There are a couple of different ways to install a thermocouple. If the tip is exposed it will not last as long as one that is sheathed with some metal alloy? It all depends on the temperature and atmosphere you are exposing the thermouple to.

I would recommend converting over to an "N" type thermocouple. It is harder to find extension wire for but it does not age like a "K" thermocouple. I recommend calling some large Thermocouple suppliers like Omega Engineering, or Pyromation Inc. to ask them further questions.

that is the most logical approach to that problem. however, i can tell that you have never dealt with this situation before. this is a very special ge thermocouple and they will tell you that. they will also tell their end user that the warranty will be voided if they use a different type or mfg.
Dear Sir ,

In most GE Gas Turbines, the Exhaust Thermocouple life can not be expected since it depends on the environment ?!

Anyway ,we represent Fenwal Controls in the UAE, and most GE Gas Turbines have Fenwal Thermocouples and I guess we should be able to help you on that issue..

Alaa Ayoub
Area Sales Engineer
[email protected]
Tel - +971 2 6795333
Fax - +971 2 6794609
The type K thermocouple used in the GE gas turbine exhaust has a varying life expectancy based on a number of factors. The thermocouple life may be shortened by repeated cycling of the temperature. Depending on who manufactured the thermocouple, the sensor may have been "preaged" to compensate for drift. The bottom line is, there is no good way to estimate the life expectancy of a thermocouple. I would suggest you contact a company known for experience with manufacturing sensors for gas turbines like Thermo Electric, Pyco, or Pyromation.