Hello,

Sanitary connections (like these:
http://www.stpats.com/sanitaryfittings.htm) can be calculated per Appendix 24. The ferrules, when welded to a shell or a pipeline, act as nozzles. It's a sort of a hubbed flange, so provisions of Appendix 2 apply (at least partially). 2-2(d)(1) permits to machine them from a forged bar, which is the most feasible way. But UG-14(b) prohibits to do so. The question is, whether 2-2(d)(1) can be understood as an exemption from UG-14(b)?



Thanks,

Konrad

Hello Konrad,
your first statement

cannot be applied without restrictions. Please note that TriClamp connections are normally not in the scope of App. 24. However, a lot of designers use App. 24 although breaking several rules, e.g.

Best regards
Michael

Michael,
Yes, but there's more than Triclamp available. And some of them comply with SecVIII-1. Only thing is they don't have right material grade marked on them, so I need to make one from scratch. What do you think about the forged bar issue?

Konrad

Konrad,
there is a Code Case, if I remember well CC 2148, which describes the use of bar material for nozzle necks. Maybe this is the loophole you are searching for.
Michael

Wasn't CC 2148 cancelled? I thought so, when they put UG-14(b) to the Code.
Konrad

Hmm... Supplement 7 (and the earlier ones) did not annul 2148. Somebody forgot auout it? Supplement 8 still is not published. For today it looks like 2148 is still valid and it doesn't feel like they're gonna put it down. Damnit, I hate the CodeCase annulation russian roulette!

CC2148 does not prohibit from making hubbed flange-like nozzles, so it's a good workaround. Thank you.

Konrad

I can still find it in the Code Case database:
http://cstools.asme.org/CodeCases.cfm
Michael

Gentlemen,

As I read the title of Appendix 2, BOLTED FLANGE, this does not apply to the clamps, does it.

Why would you want to call the Clamp a FLANGE?

However, the easiest trick to use the clamps is UG-11 Manufacturer's standard parts, which seems to be the case in this context.

Another workaround would be U-1, scope. If the clamp is butt-welded to the nozzle of the vessel, just define the clamp as "piping", and you are out of trouble.

If you do not call the clamp a flange, you can order it SA-182, which allows the use of bar as a raw material up to NPS 4.

Take care.
Dirk

Appendix 2 is about bolted flanges, right. I just needed to understand the intent of putting UG-14(b) into the code, when CC2148 is still valid

The problem is not about the clamp (it's not a part of the vessel). The problem is about the hub. Appendix24 says that the material shall comly with UG-5 thru UG-14 (does this allow using a Code Case?)

UG-11 would be applicable to a hub, when it'd be wholly cast or forged. It's not any good to turned couplings from a bar stock. And they should bear some pressure-temp rating (?!)

U-1(e)(1)(a) is indeed nice. A nozzle end not belonging to a vessel, pretty unusual approach

And UG-14(b) limitation applies to flanges only. Right, it's not a flange!

Thanks

Konrad

Dirk,



Right, but when calculating the hub per Appendix24, Table 2-7.1 is needed anyway.

Konrad