×
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

Pressure Transmitter- Temperature Rating

Pressure Transmitter- Temperature Rating

Pressure Transmitter- Temperature Rating

(OP)
I am installing Rosemount 3051S Pressure Transmitter on hot air duct. The air temperature is 400 deg C. I am using 3/8" impulse SS tubing. Pressure Transmitter temp rating is around 100 deg C. I know installing certain length of SS tubing will reduce temp. But how much, I do'nt know. Can anyone help me on this? Some book/white paper reference is appreciated.

RE: Pressure Transmitter- Temperature Rating

A magic solution that seems to last forever could fail if a technician permits the process to flow through the tubing at the manifold valve during service.  winky smile

I'm just sayin' ...

RE: Pressure Transmitter- Temperature Rating

Hey, that's just the another form of 'manifold cooking' where the more common version is when food is wrapped in aluminum foil and cooked on a car engine's manifold!  



The process world's 'manifold cooking' has better heat control through careful adjustment of the equalizing valve  :')

Dan

RE: Pressure Transmitter- Temperature Rating

(OP)
Thanks Danw2, I checked control.com thread. It is helpful. However, i am still working on my end and also talked to emerson rep., every person I discussed the answer is "Rule of Thumb" 1  foot of tubing drops 100 deg C.

Any tip or link you find let me know. Thanks

RE: Pressure Transmitter- Temperature Rating

Side note: Slope the tubing downward from the instrument back to the process.  Any condensate that forms will then run back to the process and not build up in the instrument line.

If condensate builds up in the line the other way, it will at the minimum introduce a zero error equivalent to the height of the condensate column in the sensing line.  If it's pure water, it might freeze in there, and is it has dissolved substances, it could solidify -either way you lose the true reading and get a false reading.  Could lead to a hazardous condition.  

 

RE: Pressure Transmitter- Temperature Rating

i would contact rosemount.  in similar applications i have used necked / standoff manifolds.  I was shocked at how much research has been put into temperature rating and management in the past few years when i attended a seminar a few months back.  

I have actually installed rosemount transmitters with direct mount kits directly above surface areas that contain well over 400C process.  It is a matter of getting the right sized standoff.

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