API-5L X52Q to X52QS 3

[QW Tian]

Dear Members

My specification calls for line pipe API-5L X52QS PSL2 for sour service meeting ISO 15156/NACE MR0170. Due to small quantity, my fabricator proposes to utilize ex-stock line pipe of API-5L X52Q. In order to meet API-5L X52QS, they propose to conduct additional testings in accordance with Annex H and Annex K of API-5L.
Whilst it is technically feasible to ensure the material meet the intent with the additional tests, Standard API 5L, however, states following restriction in re-certification by another party other than the mill/manufacturer as follow :

11.4.2 The manufacturer is responsible for ensuring that the pipe conforms to the requirements of each
of the certified grades. This allows pipe to be used as any of the grades individually.

11.4.4 After delivery of the pipe, no re-marking or re-certification of the pipe to a different grade or
different PSL level (PSL 1 to PSL 2) shall be permitted.

Also
3.1.43 pipe grade is defined as Designation of pipe strength level.
NOTE Chemical composition and/or heat treatment condition of a pipe grade may differ.

May I know whether anybody has a different interpretation to the above restriction on
1) Whether X52Q and X52QS are treated as different grades though both grades carry same TS and YS ?
2) Whether another party other than the mill/manufacturer is allowed to perform additional tests to re-certify the material

regards

 

[DekDee]

QW Tian,
Is the X52Q classed as PSL2 as well ?
My opinion only but X52 is the grade - changing between X52Q and X52QS is not changing the grade.
I only have an old edition of API 5L but see definition of Grades (1.3)

 

[QW Tian]

DekDee

Thankyou for your opinion. Yes, APL 5L X52Q is PSL2 as well.

Both API 5L 45th Ed (2012) and 46th Ed (2018) carry same definitions for Pipe grade as follow :

3.1.43 pipe grade - Designation of pipe strength level.
NOTE Chemical composition and/or heat treatment condition of a pipe grade may differ.

So based on this definition, I have the same opinion that upgrading X52Q PSL2 NACE MR0175 to X52QS PSL2 NACE MR0175 (with additional tests per Annex H and Annex K) is not considered a change in grade.

Should anybody else in the community have a different interpretation, I appreciate if you could share.

 

[SJones]

(2) It will be allowed at the discretion of the end user. In terms of sour service, the end user will have to be comfortable with the type, and amount, of testing to generate confidence that material not specifically manufactured for sour service has the requisite performance. In so doing, it should be ensured that the test laboratory has ISO 17025 accreditation for the selected test methods.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[GD2]

QW Tian,
I agree with SJones. In a real life world or an operating plant, things don’t happen in a ideal way. There are ways and means to do things as long as long as you can buy Owners confidence level with solid justification.

I am not sure which side role you play - Owner vs Contractor but my advice is that you raise a Technical Deviation Notice and get this approved by the Owner. As long as the fabricator meets the requirements of Annex H and K, you have a strong reason to be approved.

GDD
Canada

 

[QW Tian]

Thankyou SJones and GD2 for your opinions and well appreciated !!!

 

[SJones]

I neglected to add that the NDT company should have ISO 17020 accreditation

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.