Certifying A 193 B7 material as A 194 2H nuts. 3

[vanmorrison]

Upon recept inspection of nuts specified as A 194 2H nuts in a purchase order the vendor has certifed A 194 2H nuts when the starting material is A 193 B7.
The starting material as per the per material traceability heat # and accompanying CMTR with the material is A 193 B7.
The CMTR supplied meets the chemical percentage requirements of A 194 2H with the exception of additional elements of Cr and Mo as specified for 193 B7.
A 194 2H specifies conformance to A 962 is required. It states that the starting material shall not contain an unspecified element other than nitrogen in austentic stainless steels for the ordered grade to the extent that it then conforms to the requirements of another grade for which that element is a specified element having a minimum content.
I believe this is the situation with the material received and therefor in nonconformance to the material specification, purchase order and design requirements.
In addition the differences between heat treatment requirements between the 2 materials specification I do not fully comprehend as acceptable either.
I am shopping my concern around so that I can either put my concern to rest or for validity before I raise the issue as a material and vendor noncompliance. If concerns with compliance is valid the issue may require Regulatory involvement. The nuts are being used on a high pressure turbine. Any information or comments are welcomed.

 

[gr2vessels]

The supplier must be a Chinese one, only they can make this type of error. Your concerns are right and you should not use this material with dodgy certificates.
However, the bolts and nuts certification depends on the application, if they are directly used for pressure containment or not. If they are, the ISO 10204 cl 3.1 is the minimum certification, otherwise 2.2 certificate of conformance is required. Whichever way, the mix-up of reference standards could not happen in a decent certification.
I would not hesitate to raise the non-conformance report on this basis.
Cheers,
gr2vessels

 

[vpl]

This thread is a duplicate of thread466-281859.

As stated there, I agree with your assessment. At best you have a paperwork issue because the CMTR does not conform with the requirement. At worst, the nuts don't conform with the purchase order.

It might be possible for the nuts to be used, but that would require an engineering evaluation of the non-conforming part.

Raise the flag on this. I recommend writing a corrective action document (whatever your organization calls it.) Then any actions to resolve the non-conformance can be properly tracked to ensure traceability.



Patricia Lougheed

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[vanmorrison]

Thank you for you time in responding to my post!

 

[MJCronin]

Are these fasteners from China ?

 

[vanmorrison]

No, they are not from China.

 

[Duwe6]

A quick PMI using an X-ray Fluorescent XRF 'gun' will tell you the alloy percentages [other than carbon] and a tensile test will give the physical. Price of testing should be carried by your supplier -- sent you bad cert, maybe bad mat'l.

 

[vanmorrison]

Duwe6, Thank you for your comment. I was pondering the use of PMI instrument today! Can you read my mind?

I do not know the accuracy and confidence a PMI can provide against testing at a certified lab.

I will be recommending that the purchase and use of a PMI is evaluated to be used as an inspection tool and perform additional QA checks on applicable incoming material.

In light of international material outsourcing, concerns with fraudulent material and the fact that sincere errors can and will be made a PMI could be of value. It could serve as a secondary verification rather than reliance soly on the documetation that the supplier furnishes.

A PMI may be cheap insurance against possible worst case scenario's for example; personnel safety, mechanical failure, lost of revenue if a unit is shut down, replacement costs, regulatory confidence etc.