Extent of UG-44(b) to ASME I equipment

[CrisDom]

I'm designing a vessel according to ASME I and I'm wondering whether it's advisable/mandatory to check ASME B16.5 rating against external loads.
To be on the safe side, I decided to perform this check, considering also the statement in PG-22.1:

Stresses due to hydrostatic head shall be
taken into account in determining the minimum thickness
required unless noted otherwise. This Section does not
fully address additional loadings other than those from
working pressure or static head. Consideration shall be
given to such additional loadings.

Since this check involve the need to increase the flange rating, my client is asking me if this check for a vessel designed according to ASME I is mandatory.
I told them to refer to their Authorized Inspector (I'm still waiting for his reply), but I was wondering whether some instruction or statement can be found inside the Code, to have a certain support to my conservative approach.

Thanks to all.

Cristiana

 

[TGS4]

I would NOT advise using the calculations in UG-44(b). I would, however, point you in the direction of Code Case 2901-1. The Fm factors in the revised code case are much more accurate.

To directly answer your question, though, such a check is not necessarily mandatory according to Section I.

 

[CrisDom]

Thanks TGS4, I actually would approach the design as if I were in a general ASME design project.
Actually ASME I is strictly for boilers and there are no rules for bolted flange connections.
However I have flanged connection in my drum (that is not a boiler, nor a steam generator, but just a steam drum).
The choice of design Code is up to the Client, so their requirement is to design the drum as per ASME I rules.

This is the general picture and that's why I would refer to ASME VIII general rules rather than focus my attention only to the mandatory requirements of ASME I, even because ASME I doesn't cover all the details of my drum.
The preamble of ASME I states that "The Code does not contain rules to cover all details of design and construction. Where complete details are not given, it
is intended that the manufacturer, subject to the acceptance of the Authorized Inspector, shall provide details of design and construction which will be as safe as otherwise provided by the rules in the Code."

That's why I would recommend to take into account UG-44(b) (or CC 2901-1) even in an ASME I project, but I was wondering whether a more specific statement could be found to supporto my decision.

However, thanks for your feedback.

 

[IdanPV]

See PG-16.1:
"....This may be done by appropriate analytical methods, the appropriate use of rules from other design codes or, as permitted by PG-18, by proof test"
See also PG-11.3, PG-31.3.1, PG-42.1, PG-42.4.4.

 

[GD2]

I'm designing a vessel according to ASME I and I'm wondering whether it's advisable/mandatory to check ASME B16.5 rating against external loads.
To be on the safe side, I decided to perform this check, considering also the statement in PG-22.1:

Stresses due to hydrostatic head shall be
taken into account in determining the minimum thickness
required unless noted otherwise. This Section does not
fully address additional loadings other than those from
working pressure or static head. Consideration shall be
given to such additional loadings.

Since this check involve the need to increase the flange rating, my client is asking me if this check for a vessel designed according to ASME I is mandatory.
I told them to refer to their Authorized Inspector (I'm still waiting for his reply), but I was wondering whether some instruction or statement can be found inside the Code, to have a certain support to my conservative approach.

Thanks to all.

Cristiana

PG-22 is for main boiler components like shell, headers, drum etc , not for flange. Did you go through PG-42? Standard flanges are allowed by the Code.