This Standard for a single series of flanges specifies requirements for circular steel flanges in PN desig-nations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000. This standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses. This standard applies to flanges manufactured in accordance with the methods described in Table 1. This standard does not apply to flanges made from bar stock according to ÖNORM EN 10272 by turning. Non-gasketed pipe joints are outside the scope of this Standard.