Smart questions
Smart answers
Smart people
Join Eng-Tips Forums
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • 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!

Join Eng-Tips
*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.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

curlyjackme (Mechanical) (OP)
18 Jul 11 9:47
If an ASME vessel is going to be re-rated as an API 620 tank, can the ASME calculations be used to verify the thickness and stability of the tank? Or does a new set of API 620 calculations for the tank need to be performed?  Any opions and why.


Just for information a client has two ASME vessels that were fabricated for a project and it was shut down, now they need tanks for a new project and want to utilize these vessels instead of having new tanks fabricated.
JohnGP (Mechanical)
18 Jul 11 15:59
I'm struggling to see why the ASME vessel needs to be rerated to API 620. Normally design to an ASME vessel code would be over the top for a storage tank, but if already designed per ASME then stay with it.

There is nowhere in the ASME codes that I have dealt with that says you can't operate an ASME vessel at a lower operating pressure than it was designed for.

Of course if the tank design pressure exceeds the vessels MAWP, then you would obviously need to perform a new set of calculations.

That's my opinion anyway.
Cheers,
John
 
curlyjackme (Mechanical) (OP)
18 Jul 11 16:07
The client wants a API 620 tank instead of the ASME vessel due to in house inspection requirements.  The new design will be atmospheric.  Also the vessel/tank has 2:1 heads therefore API 620 and not 650.
 
Helpful Member!  JStephen (Mechanical)
18 Jul 11 16:35
I would assume new calculations were required, as the same methodology is not used in both standards.  For example, in times past, I found the API-620 design to be overly conservative as applied to the knuckle region- heads that would meet ASME wouldn't meet API-620 design- so don't just assume that the re-rate is feasible until you try.

ASME clearly states that tanks with pressure less than 15 psi are exempt, but may still be stamped with the ASME symbol if built in conformance to the code.
curlyjackme (Mechanical) (OP)
18 Jul 11 16:43
Thanks.  That is what I was concerned about.

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!

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close