Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges; German version EN 1092-1:2007— 131 стр.
Pipe threads where pressure-tight joints are not made on the threads - Part 1: Dimensions, tolerances and designation (ISO 228-1:2000); German version EN ISO 228-1:2003— 11 стр.