×
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

Low alloy steel corrosion testing

Low alloy steel corrosion testing

Low alloy steel corrosion testing

(OP)
Good day !
We placed an order for some equipment to be used in a high temperature/high pressure well with H2S exposure, so the material has to be NACE MR0175 compliant. The required material grade is API 5CT “T-95”low alloy steel whereas manufacturer has supplied equipment fabricated out of C95/4140 grade Quenched/Tempered Steel. The main reason of rejection is deviation in grade & SSCC test (NACE TM-0177) which was not carried out by manufacturer as required by API 5CT for T-95 garde. Upon rejection, manufacturer has justified with following response:


“As per NACE MR0175 spec paragraph A.3 which states that any Cr-Mo Low ally steel in quenched and tempered condition is accepted for use throughout SSC Region 2.
C95 or 4140 Q&T should be suitable for sour service in any region if the service temperature when exposed to sour fluids is continually 150°F or above, as per NACE Table A.3”.

My question is that without doing actual SSCC testing as per NACE TM-0177, how they can justify the above. If so, then why API 5CT categorized various grades (L 80, T-95, C95…etc)? Even without doing SSCC test, one can accept C95/4140 grade in lieu of T-95 ??


RE: Low alloy steel corrosion testing

It can't be justified. T95 is what was ordered; T95 is to be supplied. How do they know what Region applies now, or in the future? If you shut in a well, will the temperature stay above 65 deg C?

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/pub/8/83b/b04

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

RE: Low alloy steel corrosion testing

"C-95" is a mill's way of saying "We can't pass the T-95 / NACE Type 1 test" .
When T95 was first approved (over many mill objections) ,no mills in the western hemisphere could make it. Hopefully mills have gotten better since I retired; but they would have to prove it for me by passing by passing NACE test. Even if they claimed they were making T95.

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