Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

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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 fifth edition cancels and replaces the fourth edition (ISO 4018:2011), which has been technically revised.

The main changes are as follows:

— the permissible shapes for free formed head and indentation on the head have been added;
— tables for dimensions have been restructured;
— M7 has been added;
— d _w,min has been changed for M5 from s_min – IT16 to s_min – IT15 (as for hexagon head screws of product grades A and B) in order to have a larger bearing surface area and thus less contact pressure;
— the rules for the shortest and greatest standard lengths have been added, and they have been amended accordingly; standard greatest lengths have been limited to 200 mm (longer lengths are to be agreed between the purchaser and the manufacturer);
— 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 4018:2022

Fasteners. Hexagon head screws. Product grade C

Current

Published:

31 Aug 2022