kSIST FprEN 4128:2025
(Main)Aerospace series - Bolt, normal hexagonal head, coarse tolerance shank, short 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 shank, short 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 shank, short thread, in heat resisting nickel base alloy, aluminium IVD coated.
Classification: 1 250 MPa/425 °C.
Luft- und Raumfahrt - Sechskantschrauben, kurzes Gewinde, aus hochwarmfester Nickelbasislegierung, Aluminium-IVD-beschichtet - Klasse: 1 250 MPa (bei Raumtemperatur) / 425 °C
Série aérospatiale - Vis à tête hexagonale normale, fût à tolérance large, filetage court, en alliage résistant à chaud à base de nickel, revêtues aluminium IVD - Classification: 1 250 MPa (à température ambiante) / 425 °C
Le présent document spécifie les caractéristiques des vis à tête hexagonale normale, fût à tolérance large, filetage court, en alliage résistant à chaud base nickel, revêtues d'aluminium IVD.
Classification : 1 250 MPa/425 °C.
Aeronavtika - Sornik, normalna šestroba glava, široka toleranca, kratek navoj, iz toplotnoodporne zlitine na nikljevi osnovi, prevlečeni z aluminijem IVD - Klasifikacija: 1250 MPa (pri temperaturi okolice) / 425 °C
General Information
- Status
- Not Published
- Public Enquiry End Date
- 05-May-2024
- Technical Committee
- I13 - Imaginarni 13
- Current Stage
- 5020 - Formal vote (FV) (Adopted Project)
- Start Date
- 10-Mar-2025
- Due Date
- 28-Apr-2025
- Completion Date
- 10-Mar-2025
Relations
- Effective Date
- 19-Jan-2023
Overview
FprEN 4128 is a draft CEN/AeroSpace standard that specifies the characteristics of aerospace series bolts with a normal hexagonal head, coarse-tolerance shank and short thread, manufactured from a heat‑resisting nickel‑base alloy and aluminium IVD coated. The bolts are classified for a minimum tensile strength of 1 250 MPa (ambient) and rated to 425 °C (maximum temperature determined by the surface treatment). This standard defines geometry, materials, surface treatment, marking, and qualification requirements for fasteners used in high‑temperature aerospace applications.
Key topics and technical requirements
- Configuration & dimensions: Dimensions, tolerances and masses conform to ISO 3193 and ISO 5855‑2; sizes use MJ thread codes and are expressed in millimetres (values apply after surface treatment but before lubrication).
- Material: Heat‑resisting nickel‑base alloy per TR 3775, strength class 1 250 MPa.
- Surface treatment: Aluminium IVD coating requirements are referenced to prEN 6118; optional lubrication with cetyl alcohol per prEN 6117 (code E).
- Mechanical properties: Minimum hardness 36 HRC; detailed tensile, shear and fatigue performance by diameter are specified (see Table 5 in the standard).
- Roughness limits: Threads Ramax = 0.8 µm; bearing surfaces Ramax = 1.6 µm; other surfaces Ramax = 3.2 µm (values before surface treatment).
- Marking & holes: Marking follows EN 2424; hole codes for lockwire/split pin options are defined.
- Manufacturer & qualification: Producers must be an approved aerospace production organization with a quality management system (e.g. EN 9100) and follow qualification/testing protocols (ISO 9154 / EN 9133 guidance).
Applications and who uses this standard
- Primary use: High‑temperature aerospace structures and propulsion systems where fasteners must retain strength and corrosion resistance up to 425 °C.
- Typical users: Aerospace design engineers, procurement/specification specialists, fastener manufacturers, quality and certification teams, MRO organisations and OEM supply chain managers.
- Benefits: Ensures interchangeability, consistent mechanical performance, traceability and compatibility with aerospace quality systems for critical high‑temperature bolting applications.
Related standards
- ISO 3193, ISO 5855‑2 (dimensions/threads)
- TR 3775 (materials)
- prEN 6118, prEN 6117 (surface protection and lubrication)
- ISO 9154 (procurement of nickel‑alloy bolts)
- EN 2424 (marking)
- EN 9100, EN 9133 (quality and qualification procedures)
- ISO 3353‑1, ISO 7913, MIL‑DTL‑83488 (coatings/threads/quality references)
Keywords: FprEN 4128, aerospace bolts, hexagonal head bolt, nickel base alloy, aluminium IVD coating, 1250 MPa, 425 °C, aerospace standard, short thread bolt.
Frequently Asked Questions
kSIST FprEN 4128:2025 is a draft published by the Slovenian Institute for Standardization (SIST). Its full title is "Aerospace series - Bolt, normal hexagonal head, coarse tolerance shank, short 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 shank, short 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 shank, short thread, in heat resisting nickel base alloy, aluminium IVD coated. Classification: 1 250 MPa/425 °C.
kSIST FprEN 4128:2025 is classified under the following ICS (International Classification for Standards) categories: 49.025.20 - Aluminium; 49.030.20 - Bolts, screws, studs. The ICS classification helps identify the subject area and facilitates finding related standards.
kSIST FprEN 4128:2025 has the following relationships with other standards: It is inter standard links to SIST EN 4128:2016. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
kSIST FprEN 4128:2025 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
oSIST prEN 4128:2024
01-maj-2024
Aeronavtika - Sornik, normalna šestroba glava, široka toleranca, kratek navoj, iz
toplotnoodporne zlitine na nikljevi osnovi, prevlečeni z aluminijem IVD -
Klasifikacija: 1250 MPa (pri temperaturi okolice) / 425 °C
Aerospace series - Bolt, normal hexagonal head, coarse tolerance shank, short thread,
in heat resisting nickel base alloy, aluminium IVD coated - Classification: 1 250 MPa (at
ambient temperature)/425 °C
Luft- und Raumfahrt - Sechskantschrauben, kurzes Gewinde, aus hochwarmfester
Nickelbasislegierung, Aluminium-IVD-beschichtet - Klasse: 1 250 MPa (bei
Raumtemperatur) / 425 °C
Série aérospatiale - Vis à tête hexagonale normale, fût à tolérance large, filetage court,
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 4128
ICS:
49.025.20 Aluminij Aluminium
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
oSIST prEN 4128:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
oSIST prEN 4128:2024
oSIST prEN 4128:2024
DRAFT
EUROPEAN STANDARD
prEN 4128
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2023
ICS 49.030.20 Will supersede EN 4128:2016
English Version
Aerospace series - Bolt, normal hexagonal head, coarse
tolerance shank, short 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, fût à Luft- und Raumfahrt - Sechskantschrauben, kurzes
tolérance large, filetage court, en alliage résistant à Gewinde, aus hochwarmfester Nickelbasislegierung,
chaud à base de nickel, revêtues aluminium IVD - Aluminium-IVD-beschichtet - Klasse: 1 250 MPa (bei
Classification: 1 250 MPa (à température ambiante) / Raumtemperatur) / 425 °C
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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 4128:2023 E
worldwide for CEN national Members.
oSIST prEN 4128:2024
prEN 4128:2023 (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 Materials . 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 . 8
7.3 Qualification of bolts. 8
Bibliography . 9
oSIST prEN 4128:2024
prEN 4128:2023 (E)
European foreword
This document (prEN 4128:2023) 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 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 4128:2016.
prEN 4128:2023 includes the following significant technical changes with respect to EN 4128:2016:
— normative references updated;
— Clause 3 “Terms and definitions” added;
— Figure 1 updated;
— 7.2 and 7.3 revised;
— Bibliography updated;
— document editorially revised.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
oSIST prEN 4128:2024
prEN 4128:2023 (E)
1 Scope
This document specifies the characteristics of bolts, normal hexagonal head, coarse tolerance shank,
short 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
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 2424, Aerospace series — Marking of aerospace products
prEN 6118, Aerospace serie
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