Foreword

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This document was prepared by Technical Committee ISO/TC 2, Fasteners, Subcommittee SC 11, Fasteners with metric external thread, in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 185, Fasteners, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 4766:2011), which has been technically revised.

The main changes are as follows:

— for M2, l = 2 mm has been classified as too short length; M8 (l = 8 mm), M10 (l = 10 mm) and M12 (l = 12 mm) have been classified separately as short standard lengths with l_nom calculated in order to get at least 2,5 full pitches; for regular standard lengths l_nom have been calculated in order to get at least 4 full pitches;
— for stainless steel screws, grades A2 and A4 with hardness classes 12H and 21H have been added;
— non-ferrous metal screws have been deleted (as a consequence of the withdrawal of ISO 8839);
— mechanical properties of steel and stainless steel screws have been added for d < 1,6 mm (“As agreed”) in Table 3;
— for stainless steel fasteners, “As processed” has been changed to “Clean and bright”, and “Passivated” has been added in Table 3;
— specifications for marking and labelling have been added as Clause 6.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

BS EN ISO 4766:2024

Fasteners. Slotted set screws with flat point

Current

Published:

31 Jul 2024