fastners-pressure parts

[212197]

are studs/bolts used for flanges to be considered as pressure parts?

Which clause of the code sheds light on the above ?

 

[DriveMeNuts]

In what context do you mean?

There are special rules throughout the codes providing the specific requirements of bolts.

 

[212197]

my query is about studs required to assemble the nozzle flanges (of a pressure vessel) with each other

 

[david339933]

Depends. Usually when piping is attached to the flange, the vessel ends at the flange face....studs are considered piping. If it is a blind flange bolting is part of the vessel.
See U-1(e)