OT: Small Pipe Temperature Sensor

Hi all,


Related to my other post, I also need to measure some quite low temperatures (down to -50°C) in pipes. For the most part this is fine - I'll just put a thermowell in the pipe and put an RTD with a 4-20mA "hockey puck" in the head. However, some of the locations I need to measure the temperature, the pipes are only 20-30mm diameter, making thermowells impractical.


Any suggestions for monitoring temperature in that application? The pipes will be lagged, and I'd ideally like something that is replaceable/serviceable without removing the lagging.

Check out the Turck TTM miniature sensors, they might be what you are looking for.
https://www.turck.de/en/sensors-1272_compact-temperature-sensors-1498.php

Surface mount, maybe..
https://www.google.com/search?rlz=1...4k1j0i3k1j0i13k1j0i20i263i264k1.0.pt_kNGlxWUc

Stick it in a 90° bend and have it as long as you like, and also facing the direction of flow?

OR

IFM TA2105? Your fluid will fall out if you replace the sensor though.

The turck looks like it could be what I'm after. Unlike the IFM, it seems that the RTD is detachable from the sensor electronics, so as long as the RTD itself was all good I could replace the sensor without breaking into the pipe.


Putting it in a 90 degree bend was my first thought, but in a 20mm pipe it's still going to take up a lot of space. It might get to the point of having to tell them to try again with larger pipes, but I'm trying to work with them as much as I can first.


I'm trying to avoid surface mount stuff, because it's just not very industrial, and also it would be buried under lagging and impossible to maintain.


I'll check out the turck...anyone know of any other brands that do a similar thing, for comparison purposes?