DS EN 1092-1:2007
DS EN 1092-1:2007 Flanges And Their Joints - Circular Flanges For Pipes, Valves, Fittings And Accessories, Pn Designated - Part 1: Steel Flanges Defines the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/temperature ratings and approximate flange