Hi,
Does anybody know which EN standard is applicable for EN orifice flanges?
ASME/ANSI seems to have a standard for orifice flanges ASME B16.36, is there any eqvivalent EN standard? Or is there any statement in EN13445 or EN13480 that you are allowed to drill a hole in the flange similiar to holes in blind flanges?
If I want to verify a non standard EN flange which standard should I go for?

Regards

David