Selection of Series A & Series B Flanges under ASME B 16.47 3

[Venkatachalam Ponnusamy]

In Piping Flanges there are two different categories available under ASME B 16.47. one is Series A and another one is Series B.
Why two different standards for the same size of Standard Flanges, is that only for the following Purpose:-
1. Series A Flanges to withstand more piping loads
2. Series B can be compact in size where we can use in space limitations & offshore applications in platforms.
is there any other purpose / advantages ? and how to select which series i have to go for, since we have difference in pricing & handling during fabrication.

Request for your valuable response in this reg.

Regards,
Venkat

 

[Geoff13]

Once upon a time they were 2 separate standards, and when they merged under B16.47 they became series A and B.
Series A is the new designation for the MSS SP 44 dimensions.
Series B is the new designation for the API 605 dimensions.
Can't help on your final question as my customers always say which they want to match their other equipment.

 

[SnTMan]

Venkatachalam Ponnusamy, if it is truly your choice, Series B are somewhat less expensive to make. However it is rarely your choice, as Geoff13 says.

Check with whoever your equipment mates with.

Regards,

Mike



The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[Venkatachalam Ponnusamy]

@Geoff13 & @ Mike,

Thanks and will appreciate for your response and valuable time.

Regards,
Venkat

 

[SnTMan]

Had a job one time, customer specifies B16.47 for one of the nozzle flanges, no Series noted. My employers' policies made it impractical to get a clarification in the timeframe required for outline submittal, so I picked Series B. Prominently so noted on the drawing. Said drawing proceeds thru multiple rounds of review and revision with no comment related to the flange selection.

Guess what happened next? After my company quotes the adder, customer decides finds it more suitable to change their flange

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[bcd]

Series B is from API and was developed for pipelines. Mostly pipe to pipe connections. Series B is more compact and the pattern can be sometimes difficult to fit on equipment such as pumps and valves. Most valves and other equipment attaching to pipe use Series A because it is larger and easier to fit on the product.

 

[jtseng123]

I will give you my experience since 1990.
The first 15 years, every EPC project was Series B, written in vessel spec. Most engineering companies also specified series B. In some rare cases that series A will be used.
After screwing up couple of occasions forgot to switch to series A to match pump connection, which normally is series A, company decided to use Series A for every project without exception, and written in the spec.

 

[TGS4]

Here's my thoughts about Series A vs Series B:

Series A:
Formerly MSS SP 44 Flanges
Tend to be more expensive
Generally heavier and stronger, so can handle more external loads
Same pressure-temperature rating as Series B
Often specified for new applications

Series B:
Formerly API 605 Flanges
Require more, but smaller bolts
Tends to have a smaller bolt circle diameter
Often specified for replacement and refurbishment applications where API 605 flanges or Series B flanges were previously used

 

[Venkatachalam Ponnusamy]

Thank you all for the responses & your shared experiences.. it really helps & understands a lot about Series A & B.
Regards,
Venkat