ISO 7040:2012
(Main)Prevailing torque type hexagon regular nuts (with non-metallic insert) - Property classes 5, 8 and 10
Prevailing torque type hexagon regular nuts (with non-metallic insert) - Property classes 5, 8 and 10
ISO 7040:2012 specifies the characteristics of prevailing torque type hexagon regular nuts (with non-metallic insert) with threads from M3 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.
Écrous hexagonaux normaux autofreinés (à anneau non métallique) — Classes de qualité 5, 8 et 10
L'ISO 7040:2012 spécifie les caractéristiques des écrous hexagonaux normaux autofreinés (à anneau non métallique), de diamètres de filetage M3 à M36 inclus, de grade A pour les filetages jusqu'à M16 inclus et de grade B pour les filetages supérieurs à M16, et de classes de qualité 5, 8 et 10.
General Information
- Status
- Published
- Publication Date
- 13-Dec-2012
- Technical Committee
- ISO/TC 2/SC 12 - Fasteners with metric internal thread
- Drafting Committee
- ISO/TC 2/SC 12 - Fasteners with metric internal thread
- Current Stage
- 9599 - Withdrawal of International Standard
- Start Date
- 10-Jun-2025
- Completion Date
- 13-Dec-2025
Relations
- Effective Date
- 06-Jun-2022
- Revised
ISO 7040:2025 - Fasteners - Prevailing torque hexagon nuts - Regular nuts (with non-metallic insert) - Effective Date
- 12-Nov-2022
- Effective Date
- 19-Jan-2012
Overview
ISO 7040:2012 defines the characteristics of prevailing torque type hexagon regular nuts (with non‑metallic insert). It covers metric threads from M3 to M36, in property classes 5, 8 and 10, and specifies product grade A for threads up to M16 and grade B for threads above M16. Dimensions correspond to ISO 4032 plus the locking (insert) system.
Keywords: ISO 7040, prevailing torque nuts, hexagon regular nuts, non‑metallic insert, nylon insert nuts, property class 5 8 10, metric threads M3–M36.
Key topics and requirements
- Scope: Prevailing‑torque hexagon regular nuts with a non‑metallic insert (e.g., polyamide as an example material for the ring) for threads M3–M36.
- Property classes: 5, 8 and 10 - mechanical performance categories referenced to ISO 898‑2 and ISO 2320 where applicable.
- Product grades: Grade A for D ≤ M16, Grade B for D > M16 (tolerances described in ISO 4759‑1).
- Thread tolerance: 6H for internal threads.
- Dimensions: Follow ISO 4032 as the baseline; ISO 7040 adds the locking‑ring geometry (see figure and table in the standard).
- Materials and surface finishes: Nut body typically steel; insert examples include polyamide. Coating and finish requirements are referenced to ISO 4042 (electrolytic) and ISO 10683 (non‑electrolytic zinc flake).
- Inspection and acceptance: Reception and sampling per ISO 3269; surface defect limits per ISO 6157‑2.
- Designation example: “Hexagon regular prevailing‑torque nut ISO 7040 - M12 - 8”
Applications and users
Practical uses of ISO 7040 prevailing‑torque nuts include assemblies requiring vibration resistance and reusable locking (where a non‑metallic insert provides prevailing torque). Typical sectors and users:
- Fastener and component manufacturers specifying production dimensions and tolerances
- Design and mechanical engineers selecting locking nuts for machinery, automotive, rail, construction and industrial equipment
- Procurement professionals ensuring compliance with specified property classes and grades
- Quality and inspection teams performing acceptance checks and surface/coating verification
- Maintenance teams choosing compatible replacement fasteners with predictable locking performance
Related standards
ISO 7040 cross‑references and complements several ISO documents:
- ISO 4032 (hexagon regular nuts dimensions)
- ISO 261 / ISO 724 / ISO 965‑2 (metric thread standards)
- ISO 898‑2 and ISO 2320 (mechanical properties and performance)
- ISO 4759‑1 (tolerances: grades A, B)
- ISO 4042, ISO 10683 (coatings)
- ISO 3269 (reception inspection)
- ISO 6157‑2 (surface defects)
Use ISO 7040:2012 when you need standardized prevailing‑torque hexagon nuts with a non‑metallic insert and clear rules for dimensions, tolerances, material references and inspection - ensuring interchangeability and consistent locking performance across designs.
ISO 7040:2012 - Prevailing torque type hexagon regular nuts (with non-metallic insert) -- Property classes 5, 8 and 10
ISO 7040:2012 - Écrous hexagonaux normaux autofreinés (a anneau non métallique) -- Classes de qualité 5, 8 et 10
Frequently Asked Questions
ISO 7040:2012 is a standard published by the International Organization for Standardization (ISO). Its full title is "Prevailing torque type hexagon regular nuts (with non-metallic insert) - Property classes 5, 8 and 10". This standard covers: ISO 7040:2012 specifies the characteristics of prevailing torque type hexagon regular nuts (with non-metallic insert) with threads from M3 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.
ISO 7040:2012 specifies the characteristics of prevailing torque type hexagon regular nuts (with non-metallic insert) with threads from M3 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.
ISO 7040:2012 is classified under the following ICS (International Classification for Standards) categories: 21.060.20 - Nuts. The ICS classification helps identify the subject area and facilitates finding related standards.
ISO 7040:2012 has the following relationships with other standards: It is inter standard links to ISO 8501-4:2006, ISO 7040:2025, ISO 7040:1997. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase ISO 7040:2012 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of ISO standards.
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 7040
Third edition
2012-12-15
Prevailing torque type hexagon regular
nuts (with non-metallic insert) — Property
classes 5, 8 and 10
Écrous hexagonaux normaux autofreinés (à anneau non métallique) —
Classes de qualité 5, 8 et 10
Reference number
©
ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Dimensions . 2
4 Requirements and reference International Standards . 3
5 Designation . 3
Bibliography . 4
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 7040 was prepared by Technical Committee ISO/TC 2, Fasteners, Subcommittee SC 12, Fasteners with
metric internal thread.
This third edition cancels and replaces the second edition (ISO 7040:1997), of which it constitutes a minor revision.
iv © ISO 2012 – All rights reserved
INTERNATIONAL STANDARD ISO 7040:2012(E)
Prevailing torque type hexagon regular nuts (with non-metallic
insert) — Property classes 5, 8 and 10
1 Scope
This International Standard specifies the characteristics of prevailing torque type hexagon regular nuts (with
non-metallic insert), with threads from M3 up to and including M36, in product grade A for threads up to and
including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.
NOTE The dimensions of the nuts correspond to those given in ISO 4032 plus prevailing torque feature.
If other specifications are required, they can be selected from existing In
...
NORME ISO
INTERNATIONALE 7040
Troisième édition
2012-12-15
Écrous hexagonaux normaux autofreinés
(à anneau non métallique) — Classes de
qualité 5, 8 et 10
Prevailing torque type hexagon regular nuts (with non-metallic insert) —
Property classes 5, 8 and 10
Numéro de référence
©
ISO 2012
DOCUMENT PROTÉGÉ PAR COPYRIGHT
Droits de reproduction réservés. Sauf prescription différente, aucune partie de cette publication ne peut être reproduite ni utilisée sous
quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les microfilms, sans l’accord écrit
de l’ISO à l’adresse ci-après ou du comité membre de l’ISO dans le pays du demandeur.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Publié en Suisse
ii © ISO 2012 – Tous droits réservés
Sommaire Page
Avant-propos .iv
1 Domaine d’application . 1
2 Références normatives . 1
3 Dimensions . 1
4 Exigences et Normes internationales de référence . 3
5 Désignation . 3
Bibliographie . 4
Avant-propos
L’ISO (Organisation internationale de normalisation) est une fédération mondiale d’organismes nationaux de
normalisation (comités membres de l’ISO). L’élaboration des Normes internationales est en général confiée aux
comités techniques de l’ISO. Chaque comité membre intéressé par une étude a le droit de faire partie du comité
technique créé à cet effet. Les organisations internationales, gouvernementales et non gouvernementales,
en liaison avec l’ISO participent également aux travaux. L’ISO collabore étroitement avec la Commission
électrotechnique internationale (CEI) en ce qui concerne la normalisation électrotechnique.
Les Normes internationales sont rédigées conformément aux règles données dans les Directives ISO/CEI, Partie 2.
La tâche principale des comités techniques est d’élaborer les Normes internationales. Les projets de Normes
internationales adoptés par les comités techniques sont soumis aux comités membres pour vote. Leur publication
comme Normes internationales requiert l’approbation de 75 % au moins des comités membres votants.
L’attention est appelée sur le fait que certains des éléments du présent document peuvent faire l’objet de droits
de propriété intellectuelle ou de droits analogues. L’ISO ne saurait être tenue pour responsable de ne pas avoir
identifié de tels droits de propriété et averti de leur existence.
L’ISO 7040 a été élaborée par le comité technique ISO/TC 2, Éléments de fixation, sous-comité SC 12, Éléments
de fixation à filetage métrique intérieur.
Cette troisième édition annule et remplace la deuxième édition (ISO 7040:1997), qui a fait l’objet d’une
révision mineure.
iv © ISO 2012 – Tous droits réservés
NORME INTERNATIONALE ISO 7040:2012(F)
Écrous hexagonaux normaux autofreinés (à anneau non
métallique) — Classes de qualité 5, 8 et 10
1 Domaine d’application
La présente Norme internationale spécifie les caractéristiques des écrous hexagonaux normaux autofreinés (à
anneau non métallique), de diamètres de filetage M3 à M36 inclus, de grade A pour les filetages jusqu’à M16
inclus et de grade B pour les filetages supérieurs à M16, et de classes de qualité 5, 8 et 10.
NOTE Les dimensions des écrous correspondent à celles données dans l’ISO 4032 plus le système de freinage.
Si d’autres spécifications sont requises, elles peuvent être choisies dans les Normes internationales existantes,
par exemple l’ISO 261, l’ISO 724, l’ISO 898-2, l’
...
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