×
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

Tubesheets:ASME Section III, App. A-8000 interpretation.

Tubesheets:ASME Section III, App. A-8000 interpretation.

Tubesheets:ASME Section III, App. A-8000 interpretation.

(OP)
Hello,

Under the ASME code Section A-8142.1 (a) the membrane stress intensity is calculated from the larger of two equations listed.

In both equations first term under the radical appears to be through thickness shear stress (twice for SI), the second term under the radical is the average through thickness radial in-plane normal stress.  However in the second equation two terms appear outside the radical.

The first of the two terms outside the radical is the average through thickness radial in-plane normal stress.  Why is it added again?

The second term is 2*p(inside tubes)*h/P.  What does this represent?  It appears to be some sort of in-plane stress in the ligament due to pressure in the tubesheet hole, but isn't this covered by the average radial in-plane stress which is the sum of the radial stresses calculated in A-8132.2-A-8132.4 where A-8132.4 is in-plane stress due to pressure in the tubes?!

If anyone can help me that would be great, or if anyone has information on the derivation of the two equations in A-8142.1 (a) I would greatly appreciate it.

Thanks for your time,

Graeme Cooke

RE: Tubesheets:ASME Section III, App. A-8000 interpretation.

(OP)
To add:

If I am interpreting it correctly the two terms outside the radical are for calculating the SI between the normal stress in the ligament due to pressure and the normal in plane radial stress averaged in the ligament.

If that's the case why are they ignoring the normal stress due to pressure on both sides of the tubesheet?

RE: Tubesheets:ASME Section III, App. A-8000 interpretation.

Hey Graeme!  Did you post this question on the ASME forum or one of the structural forums?   This one doesn't get a lot of interest from the structural type people.

Questions on what gets something red-flagged?  See FAQ FAQ731-376

Patricia Lougheed

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