Yes A105 only refers to the material grade.  You'll have to specify the flange code in order to ensure the dimensional requirements are met.   

I might be able to provide a bit of insight here.

The allowable flange material substitutions that can be made, normally without further qualification, are set out in Table 5.3 in CSA Z662-07.

The general requirements (off the top of my head) for being able to use an ASTM A105 / A105N material would, first off, be that your line pipe requires no proven material notch toughness properties (i.e., CSA Z245.1 Category I) or that your Design Operating Stress (DOS) is at a level where a Category I material substitution can be made via the rules and / or one of the footnotes in Table 5.1 and / or Table 5.2.

I do not believe that a flange qualified by the above process requires dual certification to both codes or re-certification from ASME/ANSI to CSA.  If you tried to make the substitution the other way, re-certification or dual certification would probably be required.

In short, you *can*, indeed, use ASTM A105 / ANSI B16.5  flanges in a CSA Z662 system, but there are applicable rules and limits.

One thing that you might need to consider carefully is the flange rating at temperature.  Pressure ratings for flanges to B16.5 are de-rated for temperature starting at 38 C (100 F).  Pressure ratings for Z245.12 flanges are not de-rated for temperature, but be cautious about that.  Pressure ratings for fittings to Z245.11 *are* de-rated for temperature starting at 120 C, and I believe that valves to API-6D (pipeline valves) also follow this pressure de-rating using the same temperature factor "T".  I, personally, specify that flanges used in any Z662 pipeline system that I design are assumed to be de-rated in accordance with the same factors as apply for API-6D valves in order to avoid putting a pipeline valve into a hot pipeline and forgetting that the valve will limit the MOP.  Also be aware that at below and up to around 55 C, the ANSI flange ratings are higher than the CSA flange ratings, beyond which the reverse is true.  From a purely "flange pressure rating" point of view, then, it is advantageous to use ANSI flanges below 55 C, but it is advantageous to use CSA flanges above 55 C.

Do note the limitations below -30 C and down to a minimum of -45 C in Table 5.3.  While B31.3 323.2.2 and ASME VIII Div. 1 UCS-66 provide avenues to allow the use of materials without proven notch toughness at lower temperatures, Table 5.3 does not.  Also note that there is no such thing as a "Category III" fitting in CSA, so for fittings, you either need *no* proven notch toughness or *full* proven notch toughness (which would include examination of failure in shear as well as absorbed energy criteria) to qualify to Category II.

I don't know if any of this helps but I would certainly be prepared to offer more input if you need it.

Regards,

SNORGY.

Snorgy's comments are quite good but I'd like to expand them just a little:

- There is a CSA Interpretation out there that indicates that when a ASME B16.5 flange is used in a CSA system the normal CSA acceptance of full pressure rating to 120 C does not apply;  You would have to start to derate the flange pressure rating at temperatures above 38 C as per ASME B16.5.
- In Alberta, the local pipeline regulation says we can not use a component pressure rating higher than the applicable CSA component standard would allow which I interpret to mean that if I use an ASME B16.5 flange I must now use the lower of the CSA flange rating or the ASME flange rating. Consequently, at least in Alberta, you can't take advantage of the higher pressure rating of the ASME flanges at low temperatures.
- With the 2007 edition of Z662, the sour service requirements became a mandatory part of the Code and with it the requirement that "materials shall comply with the provisions of the sour service clause of the applicable CSA Z245 standard". Consequently, this is usually taken to mean that CSA Z245.12 flanges must be used and that unless dual certified, ASME B16.5 flanges can not be used in a Z662 sour pipeline system. However, the wording does actually allow the use of non-dual certified flanges provided someone does the legwork to ensure compliance with the sour service requirements.

rneill:

Thanks for that.

I had not thought about the Alberta Regulation, but now that you have mentioned it, I may have some spreadsheet logic to adjust in a spreadsheet tool I developed.  In which case, thank you for adding to my knowledge base in this area!

With respect to the sour service issue in Alberta, there seems to be a strong preference among our Alberta clients to default to Category II whenever a service is "sour", if only to get the slightly tighter chemistry and lower CE.  (Category II would rule out A105 and A350LF2, which at best are Cat. I and III - and there is no Cat. III).  In any event, the CSA Code does require - when taken to the letter - that the fittings, flanges and pipe are marked "SS" for "Sour Service" in order to be correctly qualified.  We usually require that ANSI flanges are designated as "NACE" when in sour service, so when they end up in a CSA installation, by that avenue we probably have been "getting away with it", so to speak.  In the past couple of years we have simply been requiring dual-certification on all fittings in CSA installations.

(I should watch what I say here...you might be a Regulator...)

 

Regards,

SNORGY.

You can rest easy, I'm not a regulator but do provide consulting on regulatory requirements so I'm quite familiar with them.

While CSA doesn't actually list Category III material as the base requirement for any pipeline, it does allow the use of Category III material in substitution for Category II material in lengths less than 100 m.  Consequently, people often use Category III materials (e.g.,  A350 LF2 Cl 1 flanges, A333 6 pipe) for the above ground piping in their sweet category II pipelines.

With regards to the ASME flanges and the designation of NACE, there is a potential problem with the generic "NACE" stamping:

a) does the "NACE" stamp mean the component complies with the latest edition of NACE MR0175/ISO 15156 as required by the CSA component standards or does it mean the component complies with the pre 2003 edition of NACE MR0175. I've asked this question a number of times and at least with valves, the answer has often been that the manufacturer complies with the old edition of NACE and does not certify compliance with the latest edition of NACE/ISO.  Not sure how this would hold up legally since NACE no longer recognizes the old standard - it is assumed to be completely gone - but it's an issue.

b) Even if the manufacturer is certifying compliance with the latest edition of NACE MR0175/ISO 15156 are they also certifying compliance with the requirements for Region 3.  Compliance with Region 3 is a requirement of the CSA standards but is not a mandatory part of the NACE/ISO document so there is still an extra validation required beyond just the NACE stamping on the component.

Dual certification is definitely the way to go here if the components are available.  However, not to confuse the issue even more, there is still a risk in that the manufacturer can only certify that the materials are in a metallurgical condition permitted by NACE/ISO and they can't certify whether or not NACE/ISO then permits those materials to be used in your service conditions.  I've had lots of issues with clients who have purchased pipeline valves for sour service which have had Austenitic Stainless Steel trim (e.g., stems) which are stamped "NACE" because the material is in the metallurgical condition required by NACE, which is assumed by the client to mean they can use the valves without further qualification in sour service, but where the actual service conditions are outside of that permitted by Part 3 of the standard.  This then leads to a need to change materials in a "NACE" stamped valve or to have the client qualify these materials on the basis of successful pre-existing service.

Don't know if you've seen this bulletin from the Alberta ERCB ?

http://www.ercb.ca/docs/documents/directives/Directive056_SourServiceMaterialsInterpretation.pdf
 

rneill:

Thanks again for another informative post.

If you only knew about the can of worms you are helping to open.

EPC firms in the upstream oil and gas business typically get irritated by people who know these details and other "minutiae"; they are usually the first to get laid off on the grounds that "...they don't help get projects done because they get bogged down in details...".  In other words, people with the most knowledge - and take the time to know it - are perceived to be of the least value.

So, "we" continue to do our best, most often getting things "almost right" but never being afforded the chance or the resources to ensure that we get it "entirely right".

There is a continuing erosion of technical expertise and the value that was once (I think) placed on it, driven by the constant quest for faster schedules and lower engineering costs.  If the trend continues, pretty soon all of the engineering will be done by a bunch of innocent flunky generalist project engineers who were never taught, never trained and never given the chance to learn and understand the technical details - and even if they were, they nonetheless survived in a culture that relegated the value of "expertise" behind the values of "cost", "schedule" and "man-hours".

We recently just obtained the new ISO-15156 standard.  Sadly, apart from me, I doubt anyone else in the company has even opened it up yet.  They are probably more concerned about what they would bill their time to...nobody wants to be non-billable.

Regards,

SNORGY.

Unfortunately, I'm extremely familiar with the can of worms to which you refer...

 

Thank you very much for the replies guys.  I too am very familiar with which you speak up, and unfortunately I believe someone at the office here got laid off because of what you speak about....which worries me because I'm the same type of person who likes to ask questions and have things done Right.  

rneill, your point about the interpretation stating if ASME flanges are used you still have to derate them up to 120C, gives me another answer to my question.  I believe our spec takes into account the info from Table 5.3 but does not take into account that temperatures need to be derated.  I'm going to have to look into this a bit more

Not sure how familiar you are with CSA Interpretations but unlike ASME interpretations they are not published together in a single place and there is no index available.  They are published as the questions are asked in the periodic "Info Updates" issued by CSA and to see what interpretations are available, you have to go through each and every "Info Update" issued by CSA. I've complained to CSA about this but to no avail so I eventually broke down and compiled my own summary.

Anyway, the interpretation I referred to was published in the July 2009 Info Update which can be found with the following link:

http://standardsactivities.csa.ca/StandardsActivities/recent_infoupdate.asp

Thanks again, rneill.

As fate would have it, I was on vacation doing something completely irrelevant when this information was published and would never have thought to go looking for it.

Probably because I am just another of those "Generalist Project Engineers" trying to do things right but not quite able to...due to the can of worms...

Crittenden, I might soon be joining your colleague...if it happens to all of us then presumably we'll all be in good company.

Regards,

SNORGY.