ASME B16.5 also doesn't cover 22".
Larger Diameter Flanges are covered in ASME B16.47. B16.47 has a Series A and a Series B and they are not compatible with each other.
The Series A Flanges were previously known as MSS SP-44 flanges and the Series B Flanges were known as API-605 flanges.
You need to be very careful to buy flanges that match your equipment and valve flanges. It's not enough to specify one flange standard and forget about it. Often valves or equipment is only offered with one flange standard and if it's not the one you requested they may not bring it to your attention. Check and double check. It's not pretty when you get a call from the field telling you your 42" alloy pipe flange doesn't match the vessel flange.
If you are matching existing piping or equipment, check the flange you are mating to, there are some other flange classes as well, like the Taylor Forge CL175 flanges that are common in existing refineries.
I hope this helps.
NozzleTwister
Houston, Texas