EN 4178:2017

Aerospace series - Screws, pan head, six lobe recess, coarse tolerance normal shank, medium length thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature) / 315 °C

This European Standard specifies the characteristics of screws, pan head, six lobe recess, coarse tolerance normal shank, medium length thread, in titanium alloy, anodized, MoS2 lubricated.
Classification: 1 100 MPa  ) / 315 °C  ).

Luft- und Raumfahrt - Flachkopfschrauben mit Sechs-Bogenzahn, mit mittlerer Gewindelänge, aus Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1 100 MPa (bei Raumtemperatur) / 315 °C

Diese Europäische Norm legt die Eigenschaften von Flachkopfschrauben mit Sechs-Bogenzahn und mittlerer Gewindelänge aus Titanlegierung, anodisiert, MoS2-geschmiert, fest.

Série aérospatiale - Vis à tête cylindrique, à empreinte six lobes, tige normale à tolérance large, filetage moyen, en alliage de titane, anodisées, lubrifiées MoS2 - Classification: 1 100 MPa (à température ambiante) / 315 °C

Aeronavtika - Vijaki, valjasta glava, šestzoba vdolbina, široka toleranca, srednja navojna dolžina, iz titanove zlitine, anodizirani, mazani z MoS2 - Klasifikacija: 1100 MPa (pri temperaturi okolice)/315 °C

Ta standard določa lastnosti vijakov: valjasta glava, šestzoba vdolbina, široka toleranca, srednja navojna dolžina, iz titanove zlitine, anodizirani, mazani z MoS2.
Klasifikacija: 1100 MPa/315 °C.

General Information

• Status: Published
• Publication Date: 17-Jan-2017
• Withdrawal Date: 30-Jul-2017
• ICS: 49.030.10 - Screw threads
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 3 - Mechanical
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 18-Jan-2017
• Completion Date: 18-Jan-2017
• Ref Project: SIST EN 4178:2017 - Aerospace series - Screws, pan head, six lobe recess, coarse tolerance normal shank, medium length thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315 °C

Relations

• Replaces: EN 4178:2009 - Aerospace series - Screws, pan head, six lobe recess, coarse tolerance normal shank, medium length thread, in titanium alloy, anodized, MoS2 lubricated - 1 100 MPa (at ambient temperature) / 315 °C
• Effective Date: 06-Feb-2013

Overview

EN 4178:2017 is a European standard published by CEN that specifies the technical requirements for aerospace-grade screws. These screws feature pan heads with a six lobe recess, coarse tolerance normal shanks, and medium-length threads. Made from anodized titanium alloy and lubricated with molybdenum disulphide (MoS2), these screws are classified for high strength of 1100 MPa at ambient temperature and can withstand temperatures up to 315 °C without compromising their material properties.

The standard updates and replaces the EN 4178:2009 version, ensuring current aerospace industry practices and quality management guidelines are integrated. EN 4178:2017 aims to guarantee uniformity, reliability, and exceptional mechanical performance of titanium alloy screws used in demanding aerospace applications.

Key Topics

• Material Specifications: Titanium alloy with a strength classification of 1100 MPa, meeting TR 3775 material requirements, provides optimal strength-to-weight ratio essential for aerospace components.
• Design and Dimensions: Specifies detailed dimensional and tolerance requirements, including standard thread codes (MJ threads), head dimensions, and normal shank geometry, all post anodizing but prior to MoS2 lubrication.
• Surface Treatment and Lubrication: The screws are anodized for corrosion resistance and lubricant application with MoS2 coatings compliant with EN 2491, ensuring friction reduction and improved assembly performance.
• Mechanical Properties: Screws maintain integrity at ambient strength and elevated temperatures up to 315 °C, providing reliability in high-stress and high-temperature environments.
• Standardized Marking and Designation: Markings follow EN 2424, ensuring traceability and conformity. The designation system includes screw type, size codes, length, hole options (lockwire, split pin), and lubricant codes for standardized identification.
• Quality Management: Reference to EN 9100 and EN 9133 for manufacturer approval and product qualification reinforces compliance with aerospace quality management systems.

Applications

• Aerospace Fastening: EN 4178 screws are tailored for the aerospace industry, used in aircraft airframes, engines, and structural assemblies requiring high-performance fasteners that resist corrosion, thermal stress, and mechanical load.
• High-Temperature Environments: Suitable for aerospace components exposed to temperatures near 315 °C, such as engine compartments and thermal shields.
• Precision Engineering: Ideal for aerospace applications needing tight tolerances and consistent mechanical properties for safety-critical fastening solutions.
• Defense and Spacecraft: Their robust mechanical characteristics make these screws apt for use in defense systems and spacecraft where reliability is critical under harsh operating conditions.

Related Standards

• EN 2424: Aerospace marking requirements ensuring consistent product identification.
• EN 2491: Defines coating methods for molybdenum disulphide (MoS2) dry lubricants applied on aerospace fasteners.
• EN 3911: Geometrical definitions for six lobe recess drives used in these screws.
• EN 9100: Quality management system requirements specific to aviation, space, and defense sectors.
• EN 9133: Qualification procedures for aerospace standard parts assuring product consistency.
• ISO 3353-1 & ISO 5855-2: Specifications for aerospace thread profiles and dimensions.
• ISO 7913 & ISO 9152: Guidelines on tolerances of form, position, and procurement criteria for titanium alloy bolts and screws.
• TR 3775 & TR 4070: Technical reports covering materials and commercial MoS2 coatings relevant to aerospace fasteners.

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This comprehensive standard facilitates uniform production and quality assurance of titanium alloy pan head screws with six lobe recesses in aerospace applications, supporting critical safety and performance demands. Adherence to EN 4178:2017 ensures enhanced component reliability, ease of assembly, and durability in challenging environments.

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2017
1DGRPHãþD
SIST EN 4178:2010
Aeronavtika - Vijaki, valjasta glava, šestzoba vdolbina, široka toleranca, srednja
navojna dolžina, iz titanove zlitine, anodizirani, mazani z MoS2 - Klasifikacija: 1100
MPa (pri temperaturi okolice)/315 °C
Aerospace series - Screws, pan head, six lobe recess, coarse tolerance normal shank,
medium length thread, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100
MPa (at ambient temperature)/315 °C
Luft- und Raumfahrt - Flachkopfschrauben mit Sechs-Bogenzahn, mit mittlerer
Gewindelänge, aus Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1 100 MPa
(bei Raumtemperatur)/315 °C
Série aérospatiale - Vis à tête cylindrique, à empreinte six lobes, tige normale à
tolérance large, filetage moyen, en alliage de titane, anodisées, lubrifiées MoS2 -
Classification : 1 100 Mpa (à température ambiante)/315 °C
Ta slovenski standard je istoveten z: EN 4178:2017
ICS:
49.025.30 Titan Titanium
49.030.10 Navoji Screw threads
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 4178
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2017
EUROPÄISCHE NORM
ICS 49.030.10 Supersedes EN 4178:2009
English Version
Aerospace series - Screws, pan head, six lobe recess, coarse
tolerance normal shank, medium length thread, in
titanium alloy, anodized, MoS2 lubricated - Classification:
1 100 MPa (at ambient temperature) / 315 °C
Série aérospatiale - Vis à tête cylindrique, à empreinte Luft- und Raumfahrt - Flachkopfschrauben mit Sechs-
six lobes, tige normale à tolérance large, filetage Bogenzahn, mit mittlerer Gewindelänge, aus
moyen, en alliage de titane, anodisées, lubrifiées MoS2 Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1
- Classification: 1 100 MPa (à température ambiante) / 100 MPa (bei Raumtemperatur) / 315 °C
315 °C
This European Standard was approved by CEN on 4 March 2016.

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, 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 and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4178:2017 E
worldwide for CEN national Members.

Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Required characteristics . 5
4 Designation . 8
5 Marking . 8
6 Technical specification . 8
Annex A (informative) Standard evolution form . 9

European foreword
This document (EN 4178:2017) 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 European
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 July 2017, and conflicting national standards shall be
withdrawn at the latest by July 2017.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN 4178:2009.
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 and the United Kingdom.
1 Scope
This European Standard specifies the characteristics of screws, pan head, six lobe recess, coarse
tolerance normal shank, medium length thread, in titanium a
...