SIST EN 3228:2022

Aerospace series - Nuts, hexagonal, plain, reduced height, normal across flats, in steel, cadmium plated - Classification: 900 MPa (at ambient temperature)/235 °C

This document specifies the characteristics of plain hexagonal nuts, reduced height, normal across flats, in steel, cadmium plated, for aerospace applications.
Classification: 900 MPa/235 °C.

Luft- und Raumfahrt - Flache Sechskantmuttern mit reduzierter Höhe, normale Schlüsselweite, aus Stahl, verkadmet - Klasse: 900 MPa (bei Raumtemperatur)/235 °C

Dieses Dokument legt die Eigenschaften von einfachen Sechskantmuttern mit reduzierter Höhe und normaler Schlüsselweite aus kadmiertem Stahl für Anwendung in der Luft- und Raumfahrt fest.
Klasse: 900 MPa/235 °C .

Série aérospatiale - Écrous hexagonaux ordinaires, hauteur réduite, surplats normaux, en acier, cadmiés - Classification : 900 MPa (à température ambiante)/235 °C

Le présent document spécifie les caractéristiques des écrous hexagonaux ordinaires, de hauteur réduite, à surplats normaux, en acier, cadmiés, pour applications aérospatiales.
Classification : 900 MPa/235 °C.

Aeronavtika - Matice, šestrobe, drsne, z normalnim zevom ključa, iz jekla, kadmirane - Klasifikacija: 900 MPa (pri temperaturi okolice)/235 °C

Ta dokument določa značilnosti drsnih kadmiranih šestrobih matic iz jekla z normalnim zevom ključa za uporabo v aeronavtiki. Klasifikacija: 900 MPa/235 °C.

General Information

• Status: Published
• Public Enquiry End Date: 30-Nov-2020
• Publication Date: 11-Apr-2022
• ICS: 21.060.20 - Nuts
• ICS: 49.025.10 - Steels
• ICS: 49.030.30 - Nuts
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 06-Apr-2022
• Due Date: 11-Jun-2022
• Completion Date: 12-Apr-2022
• Ref Project: EN 3228:2022 - Aerospace series - Nuts, hexagonal, plain, reduced height, normal across flats, in steel, cadmium plated - Classification: 900 MPa (at ambient temperature)/235 °C

Relations

• Replaces: SIST EN 3228:2010 - Aerospace series - Nuts, hexagonal, plain, reduced height, normal across flats, in steel, cadmium plated - Classification: 900 MPa (at ambient temperature)/235 °C
• Effective Date: 06-Apr-2022
• Refers: oSIST prEN 13075-2:2026 - Bitumens and bituminous binders - Determination of breaking behaviour - Part 2: Determination of fines mixing time of cationic bituminous emulsions
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2133:2021 - Aerospace series - Cadmium plating of steels with specified tensile strength ≤ 1 450 MPa, copper, copper alloys and nickel alloys
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2448:2009 - Aerospace series - Steel FE-PL1503 (35CrMo4) - 900 MPa ≤ Rm ≤ 1 100 MPa - Bars - De ≤ 40 mm
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2205:2009 - Aerospace series - Steel FE-PL1502 (25CrMo4) - 900 MPa ≤ Rm ≤ 1 100 MPa - Bars - De ≤ 40 mm
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2438:2009 - Aerospace series - Steel FE-PL2102 (35NiCr6) - 900 MPa ≤ Rm ≤ 1 100 MPa - Bars - De ≤ 40 mm
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2944:2001 - Aerospace series - Inserts, screw thread, helical coil, self-locking, in corrosion resisting steel FE-PA3004
• Effective Date: 28-Jan-2026
• Refers: SIST EN 840-6:2004+A1:2008 - Mobile waste containers - Part 6: Safety and health requirements
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2424:2008 - Aerospace series - Marking of aerospace products
• Effective Date: 28-Jan-2026
• Referred By: SIST EN 2850:2018 - Aerospace series - Carbon fibre thermosetting resin unidirectional laminates - Compression test parallel to fibre direction
• Effective Date: 28-Jan-2026
• Revised: SIST EN 3238:2011 - Aerospace series - Metallic materials - Test method - Shear test for wires and rivets
• Effective Date: 26-Jun-2019

Overview

SIST EN 3228:2022 is an internationally recognized standard developed by the Slovenian Institute for Standardization (SIST) and based on the European Standard EN 3228:2022. This document specifies the requirements for plain hexagonal nuts with reduced height, manufactured from steel and cadmium plated, designed for aerospace applications. The nuts are classified for use at a tensile strength of 900 MPa (at ambient temperature) and up to 235 °C.

Standardizing these components ensures high reliability, safety, and interchangeability for critical aerospace assemblies. The technical specifications and quality criteria set out in SIST EN 3228:2022 support manufacturers, suppliers, and maintenance organizations in meeting stringent aerospace industry demands.

Key Topics

• Product Requirements: Defines key characteristics of hexagonal nuts, including reduced height and standard width across flats, manufactured in steel and finished with cadmium plating.
• Performance Classification: Specifies mechanical classification of the nuts - 900 MPa tensile strength and maximum operating temperature of 235 °C.
• Dimensional Standards: Dimensions and tolerances provided as per referenced international standards such as ISO 9609 and ISO 5855-2.
• Surface Protection: Details cadmium plating requirements for corrosion resistance, following EN 2133.
• Marking and Identification: Requirements for proper marking according to EN 2424 ensure traceability and authenticity.
• Quality Assurance: Mandates an aerospace-standard quality management system, with reference to EN 9100 for production and supply.

Applications

The plain hexagonal nuts specified in SIST EN 3228:2022 are essential fasteners in:

• Airframe Structures: Used in primary and secondary structural assemblies where reduced-height nuts are required due to space constraints.
• Aerospace Powerplants: Suitable for engine mounting and related assemblies, where heat and strength requirements are critical.
• Component Mounting: Ideal for fastening subsystems, panels, and brackets within both civil and military aircraft.
• Maintenance and Repair: The standard promotes ease of sourcing replacement nuts with guaranteed compatibility and performance, aiding maintenance, repair, and overhaul (MRO) operations.
• Other High-Performance Sectors: The high mechanical performance and environmental resistance make these nuts appropriate for other sectors requiring robust, temperature-resistant fastening solutions.

Related Standards

SIST EN 3228:2022 refers to numerous other harmonized standards, including:

• EN 2133: Aerospace series - Cadmium plating of steels.
• EN 2205, EN 2438, EN 2448, EN 3513: Define suitable steel materials for aerospace fasteners.
• ISO 9609: Dimensional requirements for hexagonal, plain, reduced-height nuts.
• ISO 5855-2 & ISO 8788: Thread specification and dimensional tolerances.
• ISO 9139: Procurement specifications for nuts, including technical criteria.
• EN 9100: Quality management systems for aviation, space, and defense organizations.

SIST EN 3228:2022 supersedes the previous 2010 edition, offering updated references and enhanced alignment with industry best practices.

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By adhering to SIST EN 3228:2022, aerospace manufacturers and suppliers benefit from standardized, reliable, and fit-for-purpose hexagonal nuts, supporting safety and efficiency throughout the product lifecycle. This standard also aids procurement, inspection, and continued airworthiness across global aerospace supply chains.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2022
Nadomešča:
SIST EN 3228:2010
Aeronavtika - Matice, šestrobe, drsne, z normalnim zevom ključa, iz jekla,
kadmirane - Klasifikacija: 900 MPa (pri temperaturi okolice)/235 °C
Aerospace series - Nuts, hexagonal, plain, reduced height, normal across flats, in steel,
cadmium plated - Classification: 900 MPa (at ambient temperature)/235 °C
Luft- und Raumfahrt - Flache Sechskantmuttern mit reduzierter Höhe, normale
Schlüsselweite, aus Stahl, verkadmet - Klasse: 900 MPa (bei Raumtemperatur)/235 °C
Série aérospatiale - Écrous hexagonaux ordinaires, hauteur réduite, surplats normaux,
en acier, cadmiés - Classification : 900 MPa (à température ambiante)/235 °C
Ta slovenski standard je istoveten z: EN 3228:2022
ICS:
21.060.20 Matice Nuts
49.025.10 Jekla Steels
49.030.30 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 3228
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2022
EUROPÄISCHE NORM
ICS 49.030.30 Supersedes EN 3228:2010
English Version
Aerospace series - Nuts, hexagonal, plain, reduced height,
normal across flats, in steel, cadmium plated -
Classification: 900 MPa (at ambient temperature)/235 °C
Série aérospatiale - Écrous hexagonaux ordinaires, Luft- und Raumfahrt - Flache Sechskantmuttern mit
hauteur réduite, surplats normaux, en acier, cadmiés - reduzierter Höhe, normale Schlüsselweite, aus Stahl,
Classification : 900 MPa (à température ambiante)/235 verkadmet - Klasse: 900 MPa (bei
°C Raumtemperatur)/235 °C
This European Standard was approved by CEN on 17 January 2022.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, 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
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 3228:2022 E
worldwide for CEN national Members.

Contents Page
European Foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 5
4 Required characteristics . 5
4.1 Configuration — Dimensions — Masses . 5
4.2 Materials . 8
4.3 Surface treatment . 8
5 Designation. 8
6 Marking . 8
7 Technical specification . 9
8 Quality management system . 9
Bibliography . 10

European Foreword
This document (EN 3228:2022) 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 September 2022 and conflicting national standards
shall be withdrawn at the latest by September 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: 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 an
...