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ASME B16.47 Series A or B?

ASME B16.47 Series A or B?

ASME B16.47 Series A or B?

I am a junior in mechnical engineering and hope you help
in any assistance.
1)What is the different between ASME B16.47 series A and
series B?
2)What is the choice of selection for using ASME B16.47
series A or series B?
3)What is the Benefits and limitations of ASME B16.47
series A and B?
Your help be highly appreciate.

RE: ASME B16.47 Series A or B?


Large bore flanges (above NPS 24") to ASME B16.47-Serie A or MSS-SP 44 are heavier/stronger than the ASME B16.47-Series B in the same size and pressure rating.
In most end-users piping specifications the Serie A is specified, which can whithstand more external loadings than the Serie B type.
For both series the dimensions are different. From a commercial point of view, the serie B type may be selected for piping with a non critical application.

Do you have design parameters?

Note that stress engineers may be of help regarding maximum allowable external loadings.



RE: ASME B16.47 Series A or B?

You must specify one or the other so that the piping flanges mate the valve flanges.  FKE makes a good point regarding series A being a heavier design.  At least I was not aware.

RE: ASME B16.47 Series A or B?

I don't think the Series B are being properly characterized in the response, above.  The Series B uses more, but smaller bolts, so the bolt circle diameter is less, so the flange moment (essentially proportional to the distance between the bolt circle and gasket circle) is less for a given total bolt load.  As a result, the flange does not need to be as thick.  One could argue that it is simply a more efficient design.

RE: ASME B16.47 Series A or B?


The problem with large flange series A and B are that there are a mixture of them out there in the field.

Generally speaking, newer equipment almost always uses series A, but if you are connecting to a nozzle on older or existing equipment, get someone to verify the flange type physically.

Insist on drawings from vendors that are specific about the type of flanged connections over 24"NPS. With many firms employing newbie drafters, this subtle issue is often neglected.

My opinion only



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