prEN 3034

• Abstract:

  This document specifies the dimensions of self-locking, silver coated hexagonal nuts with captive washer and MJ-thread in heat resisting steel FE-PA92HT (A286) for aerospace applications.; Maximum test temperature of the parts is 425 °C.

• Status: Not Published
• Publication Date: 19-Oct-2027
• ICS: 49.030.30 - Nuts
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 3/S 2 - Fasteners
• Current Stage: 4060 - Closure of enquiry - Enquiry
• Start Date: 16-Jul-2026
• Completion Date: 16-Jul-2026
• Ref Project: oSIST prEN 3034:2026 - Aerospace series - Nuts, self-locking, hexagonal with captive washer, - In heat resisting steel FE-PA92HT (A286), silver coated Classification: 1100 MPa/425 °C

• Revises: EN 3034:2009 - Aerospace series - Nuts, self-locking, hexagonal with captive washer - In heat resisting steel FE-PA92HT (A286), silver coated Classification: 1100 MPa/425 °C
• Effective Date: 20-Jan-2026

Overview

prEN 3034 is a draft European Standard developed by CEN, defining self-locking, hexagonal nuts with captive washer, crafted from heat resisting steel FE-PA92HT (A286) and silver coated for specialized aerospace applications. Classified at 1100 MPa strength and a maximum test temperature of 425 °C, this standard addresses products essential for high-stress, elevated temperature environments typically found in the aerospace industry. This document outlines the key dimensional, material, and surface requirements for these nuts, ensuring consistent quality and performance across manufacturers and international markets.

Key Topics

• Product Definition: Covers hexagonal nuts that are self-locking, incorporate a captive washer, feature MJ-thread, and are made of heat-resisting FE-PA92HT (A286) steel.
• Classification: 1100 MPa/425 °C, indicating the mechanical strength and temperature resistance required.
• Material Requirements:
  • Use of high-performance heat resisting steels in line with aerospace specifications (e.g., EN 2399, EN 3638, EN 3639, TR 3791, SAE AMS5525).
• Surface Treatment:
  • Silver coating, per EN 2786, with controlled thickness, ensuring durability and corrosion resistance.
  • Washer surfaces are passivated as per EN 2516 for added protection.
• Dimensional Standards:
  • Comprehensive specifications for sizing, tolerances, mass, and other physical characteristics to ensure interchangeability and fit.
  • Dimensions are provided for several MJ thread sizes-core for aerospace mating parts.
• Marking and Traceability:
  • Compliance with EN 2424 ensures correct, traceable marking for aerospace nuts.
• Quality and Qualification:
  • Manufacturers must maintain an approved quality management system (such as EN 9100).
  • Nuts require a documented qualification process (as per EN 9133).

Applications

• Aerospace Fastening Systems: Used extensively in critical applications where high mechanical strength, heat resistance, and security against loosening are required.
• Jet Engines & Turbines: Suitable for attachment points and assemblies exposed to extreme temperatures and vibration.
• Aircraft Structural Assemblies: Ideal for high-stress joints where reliability and safety are paramount.
• Spacecraft Components: Their resistance to temperature and stress makes them suitable for spaceborne systems.
• Maintenance and Repair: Maintains compatibility with other standardized MJ-threaded aerospace fasteners, supporting efficient maintenance operations.

These self-locking nuts are integral to ensuring the structural integrity and long-term reliability of aerospace assemblies, especially in environments where temperature management and mechanical stability are crucial.

Related Standards

• EN 2399: Heat resisting steel for aerospace fasteners.
• EN 2424: Marking of aerospace products, enabling part traceability.
• EN 2516: Passivation process for corrosion resisting aerospace steels.
• EN 2786: Electrolytic silver plating of aerospace fasteners.
• EN 3152: Technical requirements for self-locking MJ thread nuts in heat resisting steel.
• EN 3638/EN 3639: Specifications for heat resisting alloys and fastener wires.
• ISO 5855-1/2: International standards for MJ threads.
• EN 9100: Quality management systems for aviation, space, and defense.
• EN 9133: Qualification procedures for aerospace standard products.
• SAE AMS5525: Material standard for heat and corrosion-resistant steel used in aerospace.

By adhering to prEN 3034, aerospace manufacturers and suppliers ensure their hardware meets rigorous European and international requirements, supporting flight safety, performance, and global interoperability.

SLOVENSKI STANDARD
01-julij-2026
Aeronavtika - Matice, samozapiralne, šestrobe, z robljeno podložko - Iz
toplotnoodpornega jekla FE-PA92HT (A286), posrebrene - Klasifikacija: 1100
MPa/425 °C
Aerospace series - Nuts, self-locking, hexagonal with captive washer, - In heat resisting
steel FE-PA92HT (A286), silver coated Classification: 1100 MPa/425 °C
Luft‑ und Raumfahrt - Sechskantmutter, selbstsichernd mit Bördelscheibe - Aus
hochwarmfestem Stahl FE‑PA92HT (A286), versilbert - Klasse: 1 100 MPa/425 °C
Ta slovenski standard je istoveten z: prEN 3034
ICS:
49.025.10 Jekla Steels
49.030.30 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2026
ICS 49.030.30 Will supersede EN 3034:2009
English Version
Aerospace series - Nuts, self-locking, hexagonal with
captive washer, - In heat resisting steel FE-PA92HT
(A286), silver coated Classification: 1100 MPa/425 °C
Luft- und Raumfahrt ¿ Sechskantmutter, selbstsichernd
mit Bördelscheibe ¿ Aus hochwarmfestem Stahl FE-
PA92HT (A286), versilbert Klasse: 1 100 MPa/425 °C
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 3034:2026 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 . 5
4.1 Configuration – Dimensions – Tolerances . 5
4.2 Material . 5
4.3 Surface treatment . 5
5 Designation . 7
6 Marking . 7
7 Technical specification . 7
7.1 General. 7
7.2 Approval of manufacturers . 7
7.3 Qualification of nuts . 8
Bibliography . 9

European foreword
This document (prEN 3034:2026) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 3034:2009 and EN 3034:2009/AC:2011.
EN 3034:2009/AC:2011:
— Clause 3, “Terms and definitions”, added;
— 4.2, “Material”, standards TR 3791 and SAE AMS5525 added;
— Clause 7, “Technical specification”, editorially revised.
1 Scope
This document specif
...