API, ISO, EN ISO, DIN EN ISO Really the same?

[GL431]

I suppose this is a "standard" type of question. I searched, got a number of hints, but not a definite answer.

When two different standard authorities issue standards with the sentence "this standard is identical to ISO ..." are these standards really identical to each other?

In my specific case: The client ordered tubular goods according to API 5 CT in its latest edition. I do not have that API in my hands. My library has DIN EN ISO 11960 (fortunately also in the English language). According to the API catalogue API 5CT should be equivalent to ISO 11960. Can I go ahead and work with the DIN EN ISO 11960 and not bother to order the API 5CT? Would be interesting to see how it pans out with the inches-mm thing.

 

[JStephen]

I think it depends.

In many cases, a standard will be developed by a technical organization, and is then made a standard of a standard organization. For example, ASME or ASCE may develop the standard, and then it also becomes an ANSI standard or something of the sort. In those cases, the standards involved are identical, and will ususally have both numbers on them.

On the other hand, if a part is produced to a standard, and also incidentally meets some other standard, that does not imply that the standards are identical- simply that the part meets both. You might have requirements in one that aren't in the other. One might have tighter tolerances. You might have different ranges of composition in each, etc.

 

[DrillerNic]

My understanding of EuroNorms and ISO standards is that they take a popular/ good standard written by someone like the API or BSI or whoever and it then becomes an ISO. So ISO 11960 IS API 5CT. However you may want to make sure teh ISO you have in the library is the latest version.

There's no real problem with mm & inches, as all the API 5 standards come in both mm and inches...

 

[dcasto]

There are joint meetings betweeen ISO and API to try to harmonize each others standards. They end up both agreeing to disagree. Bottom line, word for word they are different, but there is no way anyone can prove one is any better than the other. To me, I just standby the standard I chose and let someone else prove it wrong, not try to prove I'm right. They will run out of ammo first.

 

[SJones]

Oh, such a cynical lot. Why not try reading up on what actually is going on between bodies such as API, ISO, and CEN? You may be surprised.

http://committees.api.org/standards/isotc67/index.html

As for GL431's question, API 5CT and ISO 11960 are identical: when one purchases the API version, the front page has both API and ISO titles on it as indivisible. Both documents have been updated in unison this year. One of the API/ISO successes (in a lot of cases, the US can't bring itself to fully adopt an ISO standard and has to have a "US Annex" at the back where it reintroduces all the things that ISO changed!!!)

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/

 

[GL431]

Thanks for your input. The cross border cooperation amongst the standards authorities was quite a surprise for me.

 

[JLSeagull]

58 of about 848 active API standards include ISO in the text. Five are MPMS, several RP 5, 8, 10, 13, 14, 17, 621; Spec 2MT2, 5CT, 6A, 6D, 7-11, 14, 16, 17, Q1; STD 530, 600, 602, 610, 612, 619, 661, 662, 682 and 1512.