EN 3381:2025
(Main)Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315 °C
Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315 °C
This document specifies the characteristics of screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated.
Classification: 1 100 MPa /315 °C .
Luft- und Raumfahrt - 100°-Senk-Passschraube mit Flügelkreuzschlitz, kurzes Gewinde, aus Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1 100 MPa (bei Raumtemperatur)/315 °C
Série aérospatiale - Vis à tête fraisée 100° normale, à empreinte cruciforme déportée, tige normale à tolérance serrée, filetage court, en alliage de titane, anodisées, lubrifiées au MoS2 - Classification : 1 100 MPa (à température ambiante)/315 °C
Le présent document spécifie les caractéristiques des vis à tête fraisée 100° normale, à empreinte cruciforme déportée, tige normale à tolérance serrée, filetage court, en titane, anodisées, lubrifiées au MoS2.
Classification : 1 100 MPa /315 °C.
Aeronavtika - Vijaki, 100° ugreznjena glava, križna zareza, polno steblo, ozka toleranca, kratek navoj, iz titanove zlitine, anodizirane, mazane z MoS2 - Klasifikacija: 1 100 MPa (pri temperaturi okolice)/315 °C
General Information
Relations
Overview
EN 3381:2025 is a European standard developed by CEN that defines the specifications for aerospace-grade screws featuring a 100° countersunk normal head with an offset cruciform recess. These screws are manufactured from titanium alloy, anodized for corrosion resistance, and lubricated with molybdenum disulphide (MoS2) to enhance performance. Designed with a close tolerance normal shank and short thread, these screws meet stringent mechanical and thermal requirements, classified at 1100 MPa tensile strength at ambient temperature and capable of withstanding temperatures up to 315 °C.
This standard supersedes the 1996 edition (EN 3381:1996) and includes updates in terminology, quality management system requirements, and screw qualification protocols, aligning with modern aerospace manufacturing practices.
Key Features
- Material: Titanium alloy anodized for enhanced durability and resistance to corrosion.
- Head Design: 100° countersunk normal head for flush installation in aerospace assemblies.
- Drive Type: Offset cruciform recess, supporting secure tightening with ribbed or unribbed internal drives.
- Shank: Close tolerance normal shank ensuring precision fit and structural integrity.
- Thread: Short thread specification to suit aerospace component assembly.
- Lubrication: Coated with molybdenum disulphide (MoS2) dry lubricant as per aerospace industry standards.
- Mechanical Performance: Rated at 1100 MPa tensile strength under ambient conditions and thermal stability up to 315 °C.
Applications
The EN 3381:2025 screws are tailored specifically for aerospace applications that demand reliable, high-strength fastening solutions with precise dimensions and consistent performance under thermal stress. Key application areas include:
- Aircraft structural assembly where alloy weight reduction and high tensile strength are vital.
- Aerospace mechanical systems requiring corrosion protection and lubrication to prevent galling and wear.
- Components subjected to elevated temperatures during operation or maintenance cycles.
- High-precision fastener use in engines, airframes, and avionics enclosures.
- Replacement and maintenance parts conforming to stringent aerospace manufacturing standards.
By adhering to EN 3381:2025, manufacturers and maintenance organizations ensure compliance with industry best practices and component interchangeability in aerospace engineering.
Related Standards
EN 3381:2025 references and aligns with multiple aerospace and international standards to maintain quality and performance:
- EN 2424: Marking conventions for aerospace products, ensuring traceability.
- EN 2491: Regulations covering MoS2 dry lubricant coatings and application methods.
- EN 4016: Standards for oversized bolts used in aerospace assemblies.
- ISO 3353-1 & ISO 5855-2: Defining thread profiles, dimensions, and tolerances for aerospace screws and bolts.
- ISO 7913: Tolerances of form and position specific to aerospace fasteners.
- ISO 9152: Procurement specifications for titanium alloy MJ threads with class 1100 MPa strength.
- ISO 14275 & ISO 14276: Metric series standards for internal offset cruciform drives.
- EN 9100: Quality management systems for aviation, space, and defense organizations.
- EN 9133: Qualification procedures for aerospace standard products ensuring reliability and consistency.
Practical Value
Implementing EN 3381:2025 ensures aerospace screws used in critical applications have:
- Verified mechanical strength and resistance to environmental and thermal factors.
- Precise geometric tolerances for safe and effective assembly.
- Compatibility with aerospace-grade materials and lubricants to extend service life.
- Standardized marking and designation facilitating maintenance and replacement.
- Compliance with aerospace quality and manufacturing management systems, reducing risk of failure.
This standard benefits aerospace manufacturers, suppliers, and maintenance personnel by providing a clear, rigorous framework to select and verify titanium alloy screws meeting demanding aerospace operational environments.
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2026
Nadomešča:
SIST EN 3381:2001
Aeronavtika - Vijaki, 100° ugreznjena glava, križna zareza, polno steblo, ozka
toleranca, kratek navoj, iz titanove zlitine, anodizirane, mazane z MoS2 -
Klasifikacija: 1 100 MPa (pri temperaturi okolice)/315 °C
Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess,
close tolerance normal shank, short thread, in titanium alloy, anodized, MOS2 lubricated
- Classification: 1 100 MPa (at ambient temperature) / 315 °C
Luft- und Raumfahrt - 100° Senk-Paβschraube mit Flügelkreuzschlitz, kurzes Gewinde,
aus Titan, anodisiert, MOS2-geschmiert - Klasse: 1 100 MPa (bei Raumtemperatur) /
315 °C
Série aérospatiale - Vis à tête fraisée 100° normale, à empreinte cruciforme déportée,
tige normale à tolérance serrée, filetage court, en alliage de titane, anodisée, lubrifiée au
MoS2 - Classification : 1 100 MPa (à température ambiante)/315 °C
Ta slovenski standard je istoveten z: EN 3381:2025
ICS:
49.025.30 Titan Titanium
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN 3381
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2025
EUROPÄISCHE NORM
ICS 49.030.20 Supersedes EN 3381:1996
English Version
Aerospace series - Screws, 100° countersunk normal head,
offset cruciform recess, close tolerance normal shank,
short thread, in titanium alloy, anodized, MoS2 lubricated -
Classification: 1 100 MPa (at ambient temperature)/315
°C
Série aérospatiale - Vis à tête fraisée 100° normale, à Luft- und Raumfahrt - 100°-Senk-Passschraube mit
empreinte cruciforme déportée, tige normale à Flügelkreuzschlitz, kurzes Gewinde, aus
tolérance serrée, filetage court, en alliage de titane, Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1
anodisées, lubrifiées au MoS2 - Classification : 1 100 100 MPa (bei Raumtemperatur)/315 °C
MPa (à température ambiante)/315 °C
This European Standard was approved by CEN on 25 August 2025.
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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 3381:2025 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 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 Quality management system . 9
7.3 Qualification of screws . 9
8 Oversized bolts . 9
Bibliography . 10
European foreword
This document (EN 3381:2025) 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 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 April 2026, and conflicting national standards shall be
withdrawn at the latest by April 2026.
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.
This document supersedes EN 3381:1996.
This document includes the following significant technical changes with respect to EN 3381:1996:
— editorially updated;
— Clause 3 “Terms and definitions” added;
— SAE AMS4967 added;
— Table 3 “Drive Codes” updated;
— 7.2 “Quality management system” updated;
— 7.3 “Qualification of screws” updated.
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.
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, 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, S
...
Frequently Asked Questions
EN 3381:2025 is a standard published by the European Committee for Standardization (CEN). Its full title is "Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315 °C". This standard covers: This document specifies the characteristics of screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated. Classification: 1 100 MPa /315 °C .
This document specifies the characteristics of screws, 100° countersunk normal head, offset cruciform recess, close tolerance normal shank, short thread, in titanium alloy, anodized, MoS2 lubricated. Classification: 1 100 MPa /315 °C .
EN 3381:2025 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.
EN 3381:2025 has the following relationships with other standards: It is inter standard links to EN 3381:1996. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase EN 3381:2025 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of CEN standards.
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