×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

thermocouple & thermowell configurations

thermocouple & thermowell configurations

thermocouple & thermowell configurations

(OP)
Can someone provide some examples of reliable and accurate thermocouple and thermowell configurations applied to piping? I am most interested in the mechanical layout and sizing as opposed to the interaction of the sensor and electronics.

I am aiming to minimize heat leak to the process fluid (LNG in this case) and to decrease thermal resistance between the sensor and process fluid. One requirement that makes this difficult is the need for serviceable sensors. Currently T-type 1/4" DIA insertion probes are being used in thermowells similar to those on the site listed below.
http://www.omega.com/pptst/SERIES_260W.html
http://www.omega.com/pptst/NB1-ICIN_INDUST_TC.html

In the extreme case of improved performance, a bare sensor could be put in the process stream, but that would be very risky. (reliability, serviceability, damage to downstream equip if it fails, etc.)

RE: thermocouple & thermowell configurations

I've thought about skin temperature probes epoxied to line and then armoured wire out through the insulation.  I've done this with pipelines where there can be not thermowells.

RE: thermocouple & thermowell configurations

For good response you need a few things.
You can make a thermowell that has a high TC material as the plug (tip) (Cu or brass) and lower TC material for the body (SS).
You can also use a bare element thermocouple in it.  I have even used ones that were spring loaded to maintain contact.  Use as thin of wire as practical.
You can take it one more step and put a small amount of Mg oxide slurry in the bottom of the thermowell.  This will further improve response.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources