FprEN 4131
(Main)Aerospace series - Bolt, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated - Classification: 1 250 MPa (at ambient temperature) / 425 °C
Aerospace series - Bolt, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated - Classification: 1 250 MPa (at ambient temperature) / 425 °C
This document specifies the characteristics of bolts, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated.
Classification: 1 250 MPa / 425 °C
Luft- und Raumfahrt - Sechskantschraube, mittlere Gewindelänge, aus hochwarmfester Nickelbasislegierung, Aluminium‑IVD‑beschichtet - Klasse: 1 250 MPa (bei Raumtemperatur)/425 °C
Dieses Dokument legt Eigenschaften von Sechskantschrauben mit mittlerer Gewindelänge aus hochwarmfester Nickelbasislegierung, Aluminium IVD-beschichtet, fest.
Klasse: 1 250 MPa /425 °C .
Série aérospatiale - Vis à tête hexagonale normale, tige normale à tolérance large, filetage moyen, en alliage résistant à chaud base nickel, revêtue d’aluminium IVD - Classification : 1 250 MPa (à température ambiante)/425 °C
Le présent document spécifie les caractéristiques des vis à tête hexagonale normale, tige à tolérance large, filetage moyen, en alliage résistant à chaud base nickel, revêtues d'aluminium IVD.
Classification : 1 250 MPa /425 °C.
Aeronavtika - Sorniki, normalna šestroba glava, široka toleranca, srednja navojna dolžina, iz toplotnoodporne zlitine na nikljevi osnovi, prevlečene z aluminijem IVD - Klasifikacija: 1 250 MPa (pri temperaturi okolice)/425 °C
General Information
- Status
- Not Published
- Publication Date
- 04-Oct-2026
- Technical Committee
- ASD-STAN - Aerospace
- Drafting Committee
- ASD-STAN/D 3/S 2 - Fasteners
- Current Stage
- 4599 - Dispatch of FV draft to CMC - Finalization for Vote
- Start Date
- 11-Mar-2026
- Completion Date
- 11-Mar-2026
Relations
- Effective Date
- 12-Feb-2025
- Effective Date
- 12-Feb-2025
Overview
FprEN 4131:2025 is a European draft standard developed by CEN for the aerospace sector, defining the characteristics and requirements of bolts with normal hexagonal heads, coarse tolerance normal shanks, and medium length threads. These bolts are manufactured from a heat-resisting nickel base alloy and are coated with aluminium using the Ion Vapour Deposition (IVD) method, providing both high strength and enhanced temperature resistance. The classification covers bolts rated at 1 250 MPa minimum tensile strength at ambient temperature and suitable for use up to 425°C.
This standard ensures consistency, safety, and quality for aerospace fasteners, supporting the demanding operational environments of aviation and aerospace engineering by specifying material properties, dimensional standards, surface treatments, and manufacturing quality requirements.
Key Topics
- Bolt Configuration and Dimensions: The standard provides detailed specifications for the configuration, including hexagonal head shape, shank tolerances, and thread lengths, ensuring interoperability and interchangeability in aerospace applications.
- Material Requirements: Specifies the use of heat resisting nickel base alloys compliant with EN 2952, EN 3219, or ASD-STAN TR 3775, chosen for their durability and high-temperature performance.
- Surface Treatment: Calls for an aluminium IVD coating in accordance with MIL-DTL-83488D, enhancing corrosion resistance and maintaining material properties at elevated temperatures.
- Tolerances and Masses: Ensures all dimensions and tolerances conform to ISO and EN aerospace standards for form, position, and fit after coating.
- Classifications and Markings: Sets out clear designations based on diameter, length, hole presence (for lockwire or pins), and lubrication codes, alongside robust marking guidelines for traceability (per EN 2424).
- Manufacturer Approval and Qualification: Requires production organizations to have quality management systems (e.g., EN 9100) and to qualify bolts using accepted aerospace procedures (e.g., EN 9133).
Applications
FprEN 4131 bolts are designed for critical fastening applications within the aerospace industry, particularly where high strength and resistance to both heat and corrosion are crucial. Key applications include:
- Aircraft Airframe and Engine Assemblies: Used in structural joints and areas exposed to high operating temperatures.
- Spacecraft Components: Essential for fastening parts subjected to fluctuating and extreme temperatures.
- Military and Commercial Aviation: Provides the necessary performance for demanding aerospace platforms, supporting safety and reliability.
- Maintenance, Repair, and Overhaul (MRO) Operations: Standardized dimensions and properties facilitate sourcing and replacement, supporting fleet maintenance and part interchangeability.
The aluminium IVD coating combined with the nickel base alloy construction makes these bolts especially suitable for environments where both oxidation at high temperatures and mechanical stresses are present.
Related Standards
FprEN 4131:2025 references several other international and European standards to ensure comprehensive compliance and harmonization within the aerospace sector:
- EN 2424 - Marking of aerospace products.
- EN 2952 and EN 3219 - Heat resisting nickel base alloy bar and wire specifications.
- ISO 3193, ISO 3353-1, ISO 5855-2, ISO 7913 - Aerospace bolt dimensions, thread limits, tolerances of form, and position.
- MIL-DTL-83488D - Aluminium IVD coating processes.
- EN 9100 - Quality management systems for aviation, space, and defence.
- EN 9133 - Qualification procedure for aerospace standard products.
These references ensure that bolts produced under FprEN 4131 meet international best practices for quality, safety, and performance, enabling their use in certified aerospace programs worldwide.
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Frequently Asked Questions
FprEN 4131 is a draft published by the European Committee for Standardization (CEN). Its full title is "Aerospace series - Bolt, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated - Classification: 1 250 MPa (at ambient temperature) / 425 °C". This standard covers: This document specifies the characteristics of bolts, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated. Classification: 1 250 MPa / 425 °C
This document specifies the characteristics of bolts, normal hexagonal head, coarse tolerance normal shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated. Classification: 1 250 MPa / 425 °C
FprEN 4131 is classified under the following ICS (International Classification for Standards) categories: 49.030.20 - Bolts, screws, studs. The ICS classification helps identify the subject area and facilitates finding related standards.
FprEN 4131 has the following relationships with other standards: It is inter standard links to EN 4131:2009, EN 4131:2009/AC:2010. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
FprEN 4131 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-oktober-2025
Aeronavtika - Sorniki, normalna šestroba glava, široka toleranca, srednja navojna
dolžina, iz toplotnoodporne zlitine na nikljevi osnovi, prevlečene z aluminijem IVD -
Klasifikacija: 1 250 MPa (pri temperaturi okolice)/425 °C
Aerospace series - Bolt, normal hexagonal head, coarse tolerance normal shank,
medium length thread, in heat resisting nickel base alloy, aluminium IVD coated -
Classification: 1 250 MPa (at ambient temperature) / 425 °C
Luft- und Raumfahrt - Sechskantschraube, mittlere Gewindelänge, aus hochwarmfester
Nickelbasislegierung, Aluminium‑IVD‑beschichtet - Klasse: 1 250 MPa (bei
Raumtemperatur)/425 °C
Série aérospatiale - Vis à tête hexagonale normale, tige normale à tolérance large,
filetage moyen, en alliage résistant à chaud à base de nickel, revêtues aluminium IVD -
Classification: 1 250 MPa (à température ambiante) / 425 °C
Ta slovenski standard je istoveten z: prEN 4131
ICS:
49.025.20 Aluminij Aluminium
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
EUROPEAN STANDARD
prEN 4131
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2025
ICS 49.030.20 Will supersede EN 4131:2009
English Version
Aerospace series - Bolt, normal hexagonal head, coarse
tolerance normal shank, medium length thread, in heat
resisting nickel base alloy, aluminium IVD coated -
Classification: 1 250 MPa (at ambient temperature) / 425
°C
Série aérospatiale - Vis à tête hexagonale normale, tige Luft- und Raumfahrt - Sechskantschraube, mittlere
normale à tolérance large, filetage moyen, en alliage Gewindelänge, aus hochwarmfester
résistant à chaud à base de nickel, revêtues aluminium Nickelbasislegierung, Aluminium-IVD-beschichtet -
IVD - Classification: 1 250 MPa (à température Klasse: 1 250 MPa (bei Raumtemperatur)/425 °C
ambiante) / 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 4131:2025 E
worldwide for CEN national Members.
prEN 4131:2025 (E)
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Required characteristics . 4
4.1 Configuration — Dimensions — Masses . 4
4.2 Tolerances of form and position . 5
4.3 Materials . 5
4.4 Surface treatment . 5
5 Designation . 8
6 Marking . 8
7 Technical specification . 9
7.1 General. 9
7.2 Approval of manufacturers . 9
7.3 Qualification of bolts. 9
Bibliography . 10
prEN 4131:2025 (E)
European foreword
This document (prEN 4131:2025) 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 4131:2009/AC:2010.
prEN 4131:2025 includes the following significant technical changes with respect to
EN 4131:2009/AC:2010:
— Clause 2, Normative references, has been updated;
— Clause 3, Terms and definitions, added;
— Table 3 has been updated with new drive code references;
— the technical specification has been changed to EN 2583;
— subclause 7.4, Other modified requirement, has been updated.
prEN 4131:2025 (E)
1 Scope
This document specifies the characteristics of bolts, normal hexagonal head, coarse tolerance normal
shank, medium length thread, in heat resisting nickel base alloy, aluminium IVD coated.
1 2
Classification: 1 250 MPa / 425 °C
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
...




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