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!

*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

UW-11(a)(5)(-b) Spot

UW-11(a)(5)(-b) Spot

(OP)
Apologies for another UW-11(a)(5)(-b) post. All the threads on this website and other documentation I've read (such as Pastor's Pressure Points Newsletter) haven't quite covered my situation though.

I am reviewing the design of an existing VIII-1 vessel from the 2001 ed. It has the following RT & E details and is stamped RT-4:

X-RAY
Shell Long Joints
SPOT UW-11(b)
Head/Shell Joints
SPOT UW-11(a)(5)(-b)
Joints in Heads
SMLS

E Factor
Shell Long Joints
0.85
Head/Shell Joints
0.85
Joints in Heads
1.00

All the examples I've seen discuss when the Category A long seams are either seamless or full RT. It seems to me that UW-12(d) is satisfied because the Category B welds have been spot radiographed as per UW-11(a)(5)(-b), even though the Category A welds haven't been Fully RT'd as per UW-11(a)(5).

Can I use E=1 in the UG-32 calculation for a 2:1 seamless head if spot RT was done on both the Category A and B (Table UW-12 Type 1) welds?

RE: UW-11(a)(5)(-b) Spot

RT of long seam is irrelevant to satisfy UW-12(d). Only UW-11(a)(5)(b) need be satisfied. In other words spot RT on Head to Shell Circ.

Looks correct....spot on Long Seams, Spot on Circ Seams, + Spot for Head thickness (UW-11(a)(5)(b)). Must be RT-4 as you cannot have E=1 for head thickness with RT-3.

RE: UW-11(a)(5)(-b) Spot

I just noticed you have SPOT UW-11(a)(5)(b) under RT head/shell joints.....you can't use the single shot for UW-12(d) to increase circ joint efficiency. You would need two spots.

RE: UW-11(a)(5)(-b) Spot

(OP)
david339933, where does the two spots requirement come from? I neglected to say that the Diameter is 10' so each head to shell joint is less than 50ft as per UW-52.

edit: Or are you referring to UW-11(a)(5)(-b) where it says that the spot radiographs shall not be used to satisfy the spot radiography rules as applied to any other weld increment? i.e. one spot RT is required to satisfy UW-11(a)(5)(-b) and a second spot RT is required to satisfy the circ seam joint efficiency.

RE: UW-11(a)(5)(-b) Spot

(OP)
This link also gives good information for my situation: http://www.oakleysteel.co.uk/pressure-vessel-welde...

I had been thinking about the Category A weld mentioned in UW-12(d) as the long seam, but this link explains that I should consider an "imaginary" Category A weld in the seamless head instead. Which, therefore, lines up with david339933's post that RT of the long seam is irrelevant to UG-32 calculations.



RE: UW-11(a)(5)(-b) Spot

Yes, cannot be applied to any other weld increment. And yes, imaginary Cat. A in the head.

RE: UW-11(a)(5)(-b) Spot

(OP)
Thanks david339933 and israr1!

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


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