Defines together with EN 14399-1 and EN 14399-2, 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 classes 8.8/8 or 8.8/10 and 10.9/10.

This European Standard specifies, together with EN14399‑1 and EN14399‑2 , 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 classes 8.8/8 or 8.8/10 and 10.9/10. Bolting assemblies in accordance with this document have been designed to allow preloading of at least 0,7 f ub× A s 1) according to EN1993‑1‑8 (Eurocode 3) and to obtain ductility predominantly by plastic elongation of the bolt. For this purpose the components have the following characteristics: normal nut height (style 1), see ENISO4032 ; thread length of the bolt according to ISO888 . Bolting assemblies in accordance with this document include washers according to EN14399‑6 or to EN14399‑5 (under the nut only). NOTE Attention is drawn to the importance of ensuring that bolting assemblies are correctly used if satisfactory results are to be obtained. For recommendations concerning proper application, reference to EN1090‑2 is made. General requirements and requirements for suitability for preloading are specified in EN14399‑2 . Clamp lengths and grip lengths for the bolting assemblies are specified in the normative AnnexA.