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


UW-12(d) interpretation

UW-12(d) interpretation

UW-12(d) interpretation

How should UW-12(d) be interpreted for an ASME CODE heat exchanger that has a seamless tube side (cup forging) with a bolted cover and welded nozzles (welded shell side)? (The cup forging is an integral tubesheet/shell/flange on the tube side, with a shell welded to the shell side of the tubesheet).

It would be my understanding that the effeciency (E from UG-27) would be = 1 (for the tube side only), since there is no welding on the cric. and long. "seams" (no welding of a head), thus the seamless vessel section does not need to meet the UW-12(d) requirements. (The shell side circ. seam would meet the applicable UW effeciency.)

My concerns would be if anyone could interpret this any other way, or if there would be any exceptions.


RE: UW-12(d) interpretation


I'm not entirely sure I understand the design you describe, but for seamless tubing which does not contain the welds described in UW-11(a)(5)(b) the requirements for spot radiography in UW-12(d) would not apply and would allow E = 1 for you circumferential stress calcs.


RE: UW-12(d) interpretation

muld0020 (Mechanical)

Question: is your exchanger TEMA Type DEU heat exchanger one pas shell side, two presses tube side


RE: UW-12(d) interpretation

I don't see where the pressure or TEMA type come into play here. I'm concerned that if I have a seamless section of material on the tube side (no welds other than nozzles), should my efficiency "E" be equal to 1 or 0.85 (ref. UW-12(d)) for the shell thickness calculation (ref. UG-27). I would say per UW-1 my tube side is not welded therefore  specifically UW-12(d) does not apply, the calculation in UG-27 should use E = 1. The tube side can't be RT'd since it is one piece which is where the "E" comes into play anyway.

This is a hypothetical situation so you can assume the following:

Tube side = 3000 psig
Shell side = less than tube side
Sec. VIII Div 1
Material of Tube Side (Tubesheet/Channel Barrel) = SA350 LF2 Cl.1
Material of Shell Side (Shell) = SA516 Gr70

I just want to cover my bases and be certain that choosing E = 1 correct and justifiable.  

RE: UW-12(d) interpretation

muld0020, UW-12 assigns joint efficiencies, based on RT, for various details. You are correct in using E = 1.0 for seamless components. You will see from Type (7) that the concept of joint efficiency for corner joints, such as nozzle attachments, is not applicable.



RE: UW-12(d) interpretation

I think since there is no head to shell weld seam you are correct in using 1.0 for your efficiency for UG-27 calc.

RE: UW-12(d) interpretation

If there are no welds then there are no weld categories or joint types.  If there are no weld categories or joint types, UW-12(d) would not apply since you having nothing which puts you into UW-11(a)(5)(b).

E = 1 for the channel shell.

The tube sheet ligament efficiency will be per Part UHX for tubesheets integral to channel and shell.

If the shell side is seamless (or welded pipe) with a headed attached with a Type 7 joint, as it appears it is welded to the tubesheet by a corner joint as well, then E would also be 1 regardless of SRT to UW-11(a)(5)(b).


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!


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