×
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

With multiple MAWPs/MDMTs, where do I set my RV?

With multiple MAWPs/MDMTs, where do I set my RV?

With multiple MAWPs/MDMTs, where do I set my RV?

(OP)
I have a pressure vessel that has a U-1 form (as well as the nameplate) that has two different sets of MAWPs and MDMTs.
One MAWP is 250 psi @ -20F to 300F and the other MAWP is 85 psi @ -20F to -50F.
This vessel is operated on a 24/7 basis between -30F and -40F.
The vessel contains anhydrous ammonia and is operated at around 9"hg.

Questions:
Which MAWP do I set my RV's to? 250 psi or 85 psi or something else?
Can I operate the vessel at the conditions of -40F (with an MAWP assigned of 85 psi) with 250 psi RV?
If yes, where in ASME UG-125 does it permit this design?

I understand that manufacturers can provide additional MAWP and MDMTs, but how does an owner/operator comply? I have upload the U-1 form.

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