B31.3 Acceptance criteria issues 1

[capablanca]

Sirs:
For nonmetallic piping,Heat Fusion Bonds the ASME B31.3
Acceptance Criteria requires non unfilled and unbounded areas.OK.But wich is the MANDATORY examination that the
erector have to perform to accomplish this,in case that the
contract only indicates that the piping shall be according toB31.3?For metallic piping it seems that this point is clear,but not for nonmetallic pipelines.
Thanks for any comment on this,
Capablanca

 

[JohnBreen]

Capi,

B31.3, paragraph A341.4.1 seems to be pretty clear on the required examinations.

Regards, John

 

[capablanca]

Thanks John:
I agree with you.But here (in Chile),there is a discussion in this issue.A client says that the Acceptance
Criteria (AC) asks for "no unfilled areas,no unbounded on
joints" in absolute terms.What I think (and also you it seems to me),is that the concept is that "The AC is accepted if,once performed the examinations of A341.4,no detection is obtained of unfilled or unbounded areas"
Now the client is thinking to examinate joints whith ultrasonics and a new AC.¿What happens ,in contractual terms,if they detect some areas with some unbounded areas?
Thanks again!
Capablanca

 

[JohnBreen]

Capi,

I am glad that you made the distinction between structural integrity issues and contract issues.

The NDE methodologies prescribed by each chapter of the Code are chosen to apply a degree of rigor to the examination that is appropriate to the severity of the service. Of course, the Code will never limit the degree of rigor applied by the owner to design or examination. However, I am sure the legal people (lawyers and liars alike) will argue that if the contract calls for a piping system that is designed, fabricated, erected, tested and examined in accordance with the REQUIREMENTS of the Code, and the owner finds an indication, (by some NDE methodology that exceeds the Code requirement) that would not form a basis for rejecting the work. Keep in mind that every NDE methodology has its own (different) "threshold of perception" in detecting indications. If the prescribed NDE methodology, applied over the prescribed amount of work does not detect a rejectable indication (larger than allowed, et. al.) you have satisfied your contract. If the owner wanted a greater than Code required degree of rigor in the NDE, then it was his responsibility to write the Request for Proposal with that requirement stated unambiguously so that the bidders could include that cost in their bid.

Having said that I will continue by saying that if I was the owner and I found a disturbing indication using a more rigorous NDE methodology (or if I chose to look at more than the prescribed amount of work), I would make a repair. But since I wrote the design/construct contract, I would accept that the repair work would be a separate (new) contract.

All the above is just my opinion. I am not a lawyer and I do not speak for any Code committee in this discussion.

 

[capablanca]

Thanks again John for your valuable comments.During the weekend I thought again in the problem.Some of the conclusions (perhaps very elementary) are the following ones:
-The B31.3 code presents a civilized way to do risky projects that involve piping lines.For this ,the code stablishes ways to share responsability in a business and quality control context.
-The Owner,by means of the engineering project ,determines the quality level required to satisfy the project requirements.This by means of special instructions that defines the examination levels an the correspondent AC.Or by simply indicating that the B31.3 applies;thus the default AC applies.
-For metallic piping this is very clear in the code.The
AC are,in this case,explicitely DIAGNOSTIC TOOLS OR PROCESSES(Table 341.3.2A).
-For non metallic pipes,the wording of the AC is diferent.In table
A341.3.2a)the AC is a DECLARATION OF ENDS."no unfilled or unbounded areas...".For me it is clear that to fulfill the AC the only examinations needed are those in the B31.3,complemented with any,if it exists ,generated by the engineering.But some people argues otherwise:they say that the AC is not satisfied, if by means of any other way (say some NDT) some areas of the joint are encountered that are unfilled...
-In my opinion this changes completely the philosophy of the B31.3.¿Am I right?Do you know some literature that can help me on this?.I am sure that the quality management embedded in the B31.3(Inspection,Examination,AC,leakage tests,etc) is not a one day invention.
Best regards CAPA