ASME B16.5 RFWN - Radius on back-side of flange

[marty007]

Hello,

I might just be blind as a bat, but I can't find anything in ASME B16.5 that specifies the required radius on the backside of a RFWN flange. I've highlighted the radius in question below:

Does anyone know what this radius should be?

Cheers,
Marty

 

[SnTMan]

marty007, no more so than me

I cannot find anything on it. Odd

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

 

[LittleInch]

Well that diagram is really to define something else, but I agree it doesn't specify it.

Looking through B 16.5, 3mm radius seems to be the default radius where it is specified in general as opposed to a specific one like the inside of the ring groove.

Ask a vendor?

Or just specify it.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[SnTMan]

You'd think there'd be a statement something like "Dimensions not shown shall be the manufacturer's standard".

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

 

[marty007]

I find it interesting, because ASME B16.47 specifically addresses this radius in their flange dimension tables. It varies between 3/8" up to 15/16" depending on the flange size/class/series.

These flanges are going to be used in an ASME VIII-1 vessel, so I think I'll just follow App.2 guidelines...

Cheers,
Marty