EN 2923:2019

Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification: 600 MPa (at ambient temperature) / 425 °C

This document specifies the characteristics of hexagon plain nuts, reduced height, reduced across flats, in heat resisting steel, silver plated.
Classification: 600 MPa/425 °C.

Luft- und Raumfahrt - Flache Sechskantmuttern, verringerte Höhe, kleine Schlüsselweite, aus hochwarmfestem Stahl, versilbert - Klasse: 600 MPa (bei Raumtemperatur)/425 °C

Série aérospatiale - Écrous hexagonaux ordinaires, hauteur réduite, surplats réduits, en acier résistant à chaud, argentés - Classification: 600 MPa (à température ambiante) / 425 °C

Aeronavtika - Matice, šestrobe, drsne, z zmanjšanim zevom ključa, iz toplotnoodpornega jekla, posrebrene - Klasifikacija: 600 MPa (pri okoljski temperaturi)/425 °C

Ta dokument določa lastnosti šestrobih drsnih matic zmanjšane višine, z zmanjšanim zevom ključa, iz toplotnoodpornega jekla, posrebrenih.
Klasifikacija: 600 MPa/425 °C.

General Information

• Status: Published
• Publication Date: 02-Apr-2019
• Withdrawal Date: 30-Oct-2019
• ICS: 49.030.30 - Nuts
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 3/S 2 - Fasteners
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 03-Apr-2019
• Completion Date: 03-Apr-2019
• Ref Project: SIST EN 2923:2019 - Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat resisting steel, silver plated - Classification: 600 MPa (at ambient temperature) / 425 °C

Overview

EN 2923:2019 is a European standard developed by the Aerospace and Defence Industries Association of Europe (ASD-STAN) and adopted by the European Committee for Standardization (CEN). This standard specifies the characteristics of aerospace nuts that are hexagon plain, have a reduced height and reduced across flats dimension, are made from heat resisting steel, and are silver plated. Classified to withstand a tensile stress of 600 MPa at ambient temperature and maintain structural integrity up to 425 °C, these nuts are designed for high-performance aerospace applications where durability, heat resistance, and precise dimensional tolerances are critical.

Key Topics

• Material Specification: Nuts are made from heat resisting steel, enhancing their durability in elevated temperature environments typical in aerospace settings.
• Silver Plating: The standard mandates electrolytic silver plating with thickness ranging from 5 μm to 15 μm on external surfaces and at least 5 μm on the thread pitch diameter, improving corrosion resistance and conductivity.
• Dimensional Requirements:
  • Reduced height and across flat dimensions for weight and space optimization.
  • Dimensions and tolerances are defined in millimeters, following ISO 5855-2 for thread limits and ISO 8788 for form and position tolerances.
• Mechanical Classification: Minimum tensile strength rated at 600 MPa at ambient temperature, ensuring reliable structural performance.
• Thermal Classification: Effective up to 425 °C without permanent loss of mechanical properties.
• Marking and Identification: Compliance with EN 2424 marking requirements, including style C marking with "MJ" designation, ensuring traceability and conformity.

Applications

EN 2923:2019 nuts are specifically designed for aerospace and defense industries where components must endure extreme conditions. Key applications include:

• Aircraft Structures: Used in assemblies requiring high-strength fasteners resistant to high temperatures, such as engine mounts and exhaust assemblies.
• Spacecraft Components: Suitable for aerospace environments exposed to thermal cycling and high mechanical loads.
• High-Temperature Mechanical Systems: Ideal for applications where reduced dimensional profiles aid in weight savings without compromising strength or temperature performance.
• Maintenance and Manufacturing: Providing a standardized solution for production and maintenance processes requiring documented conformity to international aerospace fastener standards.

Related Standards

EN 2923:2019 should be interpreted and applied in conjunction with the following international and European standards for comprehensive compliance:

• EN 2424 – Marking of aerospace products; ensures nuts are properly identifiable and traceable.
• EN 2786 – Electrolytic silver plating of fasteners; specifies plating procedures and thickness.
• EN 9100 – Quality management systems for aviation, space, and defense organizations; governs manufacturer approval and process quality.
• ISO 5855-2 – MJ threads limit dimensions for aerospace bolts and nuts.
• ISO 8788 – Tolerances of form and position for metric aerospace nuts.
• ISO 9139 – Procurement specification for plain or slotted nuts.
• TR 3823-002 – Materials for aerospace hexagonal nuts including plain, slotted, and self-locking types.

Practical Value

Adhering to EN 2923:2019 ensures aerospace engineers and manufacturers utilize nuts that:

• Meet strict dimensional and mechanical criteria tailored for critical aerospace conditions.
• Possess high thermal resistance necessary for safety and functionality in engine compartments and other hot zones.
• Incorporate corrosion-resistant silver plating to extend lifecycle and reliability.
• Are marked for traceability complying with aerospace regulatory requirements.
• Facilitate interoperability across European aerospace supply chains, promoting harmonization and quality assurance.

By implementing EN 2923:2019, stakeholders in the aerospace industry gain confidence in fastener performance, reduce product variability, and satisfy rigorous safety and quality demands essential in aviation and space applications.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2019
Aeronavtika - Matice, šestrobe, drsne, z zmanjšanim zevom ključa, iz
toplotnoodpornega jekla, posrebrene - Klasifikacija: 600 MPa (pri okoljski
temperaturi)/425 °C
Aerospace series - Nuts, hexagon, plain, reduced height, reduced across flats, in heat
resisting steel, silver plated - Classification: 600 MPa (at ambient temperature) / 425 °C
Luft- und Raumfahrt - Flache Sechskantmuttern, kleine Schlüsselweite, aus
hochwarmfestem Stahl, versilbert - Klasse: 600 MPa (bei Raumtemperatur) / 425 °C
Série aérospatiae - Écrous hexagonaux ordinaires, hauteur réduite, surplats réduits, en
acier résistant à chaud, argentés - Classification: 600 MPa (à température ambiante) /
425 °C
Ta slovenski standard je istoveten z: EN 2923:2019
ICS:
21.060.20 Matice Nuts
49.030.30 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 2923
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2019
EUROPÄISCHE NORM
ICS 49.030.30
English Version
Aerospace series - Nuts, hexagon, plain, reduced height,
reduced across flats, in heat resisting steel, silver plated -
Classification: 600 MPa (at ambient temperature) / 425 °C
Série aérospatiae - Écrous hexagonaux ordinaires, Luft- und Raumfahrt - Flache Sechskantmuttern, kleine
hauteur réduite, surplats réduits, en acier résistant à Schlüsselweite, aus hochwarmfestem Stahl, versilbert -
chaud, argentés - Classification: 600 MPa (à Klasse: 600 MPa (bei Raumtemperatur) / 425 °C
température ambiante) / 425 °C
This European Standard was approved by CEN on 8 July 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 2923:2019 E
worldwide for CEN national Members.

Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Required characteristics . 4
5 Designation. 8
6 Marking . 8
7 Technical specification . 8

European foreword
This document (EN 2923:2019) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by
...