×
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

B75/B359 C12200 Finned Tube

B75/B359 C12200 Finned Tube

B75/B359 C12200 Finned Tube

(OP)
A manufacturer says his finned tube is "produced in alloy C12200 to meet mechanical, chemical, and testing requirements of ASTM B75/B359".

If I want to do Sect VIII Div 1 UG-28 calculations for this tube, do I use the External Pressure Chart NFC-1 or NFC-7 in Sect II Part D? (I am referring to lines 4 & 5 on page 186 of the 2008a addenda of Sect II, Part D.)

Thanks,
Rick

RE: B75/B359 C12200 Finned Tube

I don't have yet a copy of the 2008 addendum to Sec II-D, but unless the addendum declares the ASME II-D null, void and totally obsolete, including ASME VIII, then the UG-28 remains valid and applicable to your tubes, including also the external pressure charts. I'm sory, I could not comment on the misterious lines 4 and 5 of addendum.
Cheers,
gr2vessels

RE: B75/B359 C12200 Finned Tube

stanrick,

Quote:

A manufacturer says his finned tube is "produced in alloy C12200 to meet mechanical, chemical, and testing requirements of ASTM B75/B359".
I guess what your manufacturer is saying is that he can provide you with 2 classes of finned tubes:
 1. tubes with integral fins that meets the requirements of ASTM B359;
 2. tubes with non-integral fins where the tubes meet the requirements of ASTM B75.
(If the finned tubes are for ASME VIII-1 construction, the material designation should be ASME SB-359 or SB-75)

Quote:

If I want to do Sect VIII Div 1 UG-28 calculations for this tube, do I use the External Pressure Chart NFC-1 or NFC-7 in Sect II Part D? (I am referring to lines 4 & 5 on page 186 of the 2008a addenda of Sect II, Part D.)
For SB-359 Alloy C12200 Temper H55 or O61, use External Pressure Chart NFC-1.
For SB-75 Alloy C12200 Temper O50, use External Pressure Chart NFC-7. If the Temper is H55 or H80, use NFC-6.
(My above reply is based on the 2007 Edition of ASME II Part. I still don't have a copy of the 2008 Addenda. Check your 2008 Addenda and see what it says there.)



 

RE: B75/B359 C12200 Finned Tube

(OP)
Thanks for your responses, gr2vessels & doct9960. For what it's worth, I also got some feedback from the tube manufacturer. According to UG-8(b)(4), I need to do internal & external pressure calculations for both the finned and unfinned portions of the tube. The tube manufacturer tells me that I should use SB359 C12200 H55 for the finned portion, and SB75 C12200 050 for the unfinned ends of the tube. (I suppose this is because the process of forming the fins changes the material properties.) He also point sou that the Code is conservative, and that many people will opt for Appendix 23 and UG-101 tests instead of the calculations.

This is consistent with the guidance provided by the folks who certify our facility. Namely, the UG-27 & UG-28 calculations were developed for simple cylindrical bodies under pressure. Once you start adding fins (which I suppose can either be stiffeners or stress-concentrators) the calculation results lose accuracy, and actual test results become the more reliable method for finding allowable pressure.

All of this is quite interesting, and I am grateful to those who help enlighten me to the many intricacies of the code.

Rick

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