×
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

Define an Examination Lot per ASME B31.3

Define an Examination Lot per ASME B31.3

Define an Examination Lot per ASME B31.3

(OP)
Hello Everyone,

I am working with an ASME code fab shop that is fabricating and testing a few small piping systems (8 butt welds each) per ASME B31.3. The pipe fab shop and I have a difference in opinions on what defines a lot.

Per ASME B31.3-2014 para 341.4.1(b)(1), "not less than 5% of circumferential butt and miter groove welds shall be examined fully by random radiography in accordance with para 344.5 or by random ultrasonic examination in accordance with para. 344.6. The welds to be examined in each designated lot shall include the work product of each welder or welding operator whose welds are part of the lot."

ASME B31.3 Para. 344.1.3 note 1, "A designated lot is that quantity of piping to be considered in applying the requirements for examination in this Code. The quantity or extent of a designated lot should be established by agreement between the contracting parties before the start of work. More than one kind of designated lot may be established for different kinds of piping work. See Pipe Fabrication Institute Standard ES-48, Random Examination, for examples of lot selection.”

Per 341.4.1(b)(1), there is minimum examination required for each designated lot. Para 344.1.3. states the "designated lot should be established between the contracting parties". The fab shop is stating that they do not need to provide 5% RT on my job because they have achieved at least 5% RT based on overall manufacture (some fabrications require 100% RT). This doesn't make sense to me that they use RT from other fabrications towards minimum requirements on my fabrication. I would like your feedback on whether their interpretation of a lot is appropriate and in accordance with ASME B31.3.

Thanks in advance for your input.

RE: Define an Examination Lot per ASME B31.3

What did you specify in your contract specification????

RE: Define an Examination Lot per ASME B31.3

I understand your question metengr, but would the fab shop even be allowed to reach 5% over a scope of work that does not include that of the OP?

RE: Define an Examination Lot per ASME B31.3

Hi XL83NL;
No.

RE: Define an Examination Lot per ASME B31.3

(OP)
metengr,

Contract specifications are still being developed. When minimum required examination was not listed then questioned we were told those requirements would be met by overall manufacturer not per this single contract. This raised a red flag with me.

Let's say we have contracts A, B and C with this fab shop to build different piping systems for 3 different end users. Does their stance hold true if they use RT from contract A (100% RT) for Contract C (5% RT). It still doesn't make sense to me.

Thanks.

RE: Define an Examination Lot per ASME B31.3

To answer your last question, No. You may not use the 100% RT form Contract A to meet Contract C. Each contract lot is independent from another contract.

RE: Define an Examination Lot per ASME B31.3

" The quantity or extent of a designated lot should be established by agreement between the contracting parties before the start of work."

If you have let them start work without clarifying this requirement you may be chasing your tail for a while.
Good luck,
Cheers,
Shane

RE: Define an Examination Lot per ASME B31.3

Agree 100% with Weldstan - Cannnot use Contract A NDE to cover any other contracts.

344.1.3 states 100% examination as - "complete examination of all of a specified kind of item in a designated lot of piping."
So if all circ seams are required to be RT'd in Contract A (100%) then that is a lot of piping.

I would tell them....If they are considering all contracts to be one single lot.....they are in violation of contract A which requires 100% NDE of the entire lot....might change their tune.

RE: Define an Examination Lot per ASME B31.3

Interpretation: 3-5
Subject:
Date Issued:
File:
Progressive Examination
May 29, 1984
B31-84-009
Question: In applying the ANSI/ASME B31.3 requirements for progressive examination in 336.5.4,
random radiography is specified within "a designated lot" of piping. Is it permissible to include
piping from more than one owner in "a designated lot"?
Reply: No.

If your "end-users" are the "owners" then it is quite clear the contractor cannot combine contracts A, B & C

Cheers,
Shane

RE: Define an Examination Lot per ASME B31.3

(OP)
Thanks everyone, I appreciate your feedback. I will touch base with the supplier and let you know the outcome.

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