EN 14399-6 Hardened Washer

The EN 14399 washer is an integral component of high-strength structural bolting assemblies designed for preloaded joints, as specified under the European standard series EN 14399 . These washers are not generic flat rings; they are precisely engineered, hardened, and tempered plain washers intended for use with large series hexagon high-strength structural bolts and nuts, typically in thread sizes ranging from M12 to M36 .

Specifically, the HV bolt washer refers to washers used within the"System HV"(Hochfest Vorgespannt) assemblies, which are a distinct technical solution under EN 14399 for achieving the required ductility in preloaded connections . In this system, ductility is obtained predominantly by plastic deformation of the engaged threads . A critical requirement for these high-strength systems is that all components—bolts, nuts, and washers—must be procured from the same manufacturer to ensure complete system functionality and prevent the mixing of incompatible parts from different systems .

Furthermore, a HRC bolt washer is used in the"System HRC"assemblies, which represent another approach to preloaded joints. In this system, the required preload and ductility are achieved predominantly by plastic elongation of the bolt itself . Bolting assemblies conforming to this part of the standard may include washers according to EN 14399-5 (typically applied under the nut only) or EN 14399-6 . Regardless of the system, these specialized washers are crucial for distributing load, preventing indentation, and ensuring the reliable performance of the entire bolting assembly under the extreme demands of structural steel connections