DS EN 14399-3:2005
DS EN 14399-3:2005 High-Strength Structural Bolting Assemblies For Preloading - Part 3: System Hr - Hexagon Bolt And Nut Assemblies Defines the requirements for assemblies of high-strength structural bolts and nuts of system HR suitable for preloaded joints with large widths across flats, thread sizes M12 to M36 and property class