PN is the nominal pressure, which is 0.1 MPA in the International System of Units system and KGFCM2 in the engineering system. Pipe flanges commonly used Bar (I. E. KG force kgf/cm2,1 bar = 0.1 MPA) equipment flanges commonly used MPA.
The determination of nominal pressure should not only be based on the highest working pressure, but also on the highest working temperature and material characteristics, not only to meet the nominal pressure greater than the working pressure. The other parameter of the Flange is DN, which is the parameter representing the flange size.
