×
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

ASME B16.5 Pressure-Temperature Ratings

ASME B16.5 Pressure-Temperature Ratings

ASME B16.5 Pressure-Temperature Ratings

(OP)
Hello!

I didn't deal with ASME Codes in the past, so I hope you can help me. Thank you in advance.

Problem: I do not understand the Pressure-Temperature Ratings described in B16.5

Example: If I choose a forged ANSI 600 flange (material: A350 LF2), I can stress the flange with a pressure of 87,6 barg at a temperature of 200°C (according to Table 2-1-1). But what's with the wall thickness?  Are these ratings related to the ANSI Schedule "STD"?

with best regards
Daniel

RE: ASME B16.5 Pressure-Temperature Ratings

If you expect the flange to fail because it is overstressed, then it is way too thick.

Most folks believe a flange fails not because the steel fails but because the steel deforms and allows the gasket to become unloaded which then opens up a leak path. You might be surprised at how rigid flanges have to be to not rotate off the gasket...

ASME B16.5 flanges have no relationship to ASME pipe schedules.

jt

RE: ASME B16.5 Pressure-Temperature Ratings

(OP)
Thanks for your answer. But where can I read what wall thickness I have to choose ? By today we simply ordered flanges with the wall thickness of the pipes welded on the hub of that flanges. So no flange calculations were done so far.

I don't understand why there are then that pressure-temperature ratings without paying attention to the wall thickness of the flanges

DIN Flanges for example have always the same wall thickness or bore (same diameter and design pressure of course assumed). Therefore, pressure-temperature ratings make there more sense to me.

RE: ASME B16.5 Pressure-Temperature Ratings

Ok, so you're concerned about the thickness at the weld end where the flange is welded to the pipe... I think the simple answer is pretty much what you did: The flange should be ordered with a nominal bore to match the pipe to which it will be welded. If you read B16.5 you'll find that a simple hoop stress calc is made in checking the flange rating.

jt

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