ČSN EN 14399-8

This European Standard specifies together with EN 14399-1 and EN 14399-2, the requirements for assemblies of high-strength structural bolts and nuts of system HV suitable for preloaded joints with large width across flats, thread sizes M12 to M36 and property classes 10.9/10. Bolting assemblies (including fit bolts with nominal shank diameter d + 1 mm) in accordance with this document have been designed to allow preloading of at least 0,7 fub × As1) according to EN 1993-1-8 (Eurocode 3) and to obtain ductility predominantly by plastic deformation of the engaged threads. For this purpose, the components have the following characteristics: - nut height approximately 0,8 D; - bolt with short thread length. Bolting assemblies in accordance with this document include washers according to EN 14399-6. NOTE: Attention is drawn to the importance of ensuring that the bolting assemblies are correctly used if satisfactory results are to be obtained. For recommendations concerning proper application, reference to EN 1090-2 is made. General requirements and requirements for suitability for preloading are specified in EN 14399-2. Clamp lengths and grip lengths for the bolting assemblies are specified in the normative Annex A.