EN 4421:2007
(Main)Aerospace series - Studs, in titanium alloy TI-P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel - Strength class: 1 100 MPa (at ambient temperature)
Aerospace series - Studs, in titanium alloy TI-P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel - Strength class: 1 100 MPa (at ambient temperature)
This standard specifies the characteristics of studs in TI P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel for aerospace applications.
Strength class: 1 100 MPa )
Luft- und Raumfahrt - Stiftschrauben, aus Titanlegierung TI-P64001, MoS2 beschichtet, mit Ringsicherung aus korrosionsbeständigem Stahl - Festigkeitsklasse: 1 100 MPa (bei Raumtemperatur)
Diese Norm legt die Merkmale von Stiftschrauben aus TI-P64001, MoS2-beschichtet, mit Ringsiche¬rung aus korrosionsbeständigem Stahl, für Anwendungen in der Luft- und Raumfahrt fest.
Festigkeitsklasse: 1 100 MPa )
Série aérospatiale - Goujons, en alliage de titane TI-P64001, revêtus MoS2, avec bague de verrouillage dentelée, en acier résistant à la corrosion - Classe de résistance: 1 100 MPa (à température ambiante)
Aeronavtika - Stebelni vijaki iz titanove zlitine TI-P64001, namazani z MoS2, z nazobčanim zaklepnim obročem iz korozijsko odpornega jekla - Trdnostni razred: 1100 MPa (pri temperaturi okolice)
General Information
- Status
- Published
- Publication Date
- 19-Jun-2007
- Withdrawal Date
- 30-Dec-2007
- Technical Committee
- ASD-STAN - Aerospace
- Drafting Committee
- ASD-STAN/D 3 - Mechanical
- Current Stage
- 9093 - Decision to confirm - Review Enquiry
- Start Date
- 30-Jun-2017
- Completion Date
- 28-Jan-2026
Relations
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
Overview
EN 4421:2007 is a European standard issued by CEN, specifying the technical requirements for aerospace-grade studs made from titanium alloy TI-P64001. These studs are MoS2 (molybdenum disulfide) coated and feature a serrated locking ring made of corrosion-resistant steel. Designed for critical aerospace applications, the studs meet a strength class of 1,100 MPa at ambient temperature, ensuring reliability and high-performance under demanding conditions.
This standard provides comprehensive guidelines for material properties, dimensions, surface treatment, and marking to guarantee consistent quality and interchangeability in aerospace manufacturing and maintenance.
Key Topics
Material Specifications
The studs are manufactured using titanium alloy TI-P64001, known for its excellent strength-to-weight ratio and corrosion resistance. The locking rings are made from corrosion-resistant steel per AMS 5604R standards to ensure durability in harsh environments.Strength Class
EN 4421 defines a minimum tensile strength of 1,100 MPa at ambient temperature, ensuring that these studs can withstand the mechanical stresses of aerospace structures.Surface Treatment
The studs receive an MoS2 (molybdenum disulfide) coating to reduce friction during installation and to facilitate better locking performance. This coating also enhances wear resistance and lubrication.Design and Dimensions
The standard includes precise dimensions, tolerances, and thread profiles for the studs and locking rings to guarantee fit and function. Threads comply with aerospace threading standards such as ISO 3353 and ISO 5855-2 to support interoperability.Marking and Traceability
Markings conform to EN 2424 standards, allowing clear identification of part numbers, material, and manufacturing details, facilitating traceability throughout the aerospace supply chain.Technical Testing Requirements
The studs must undergo ring rotational integrity tests as outlined in EN 4458 to ensure the locking ring maintains proper engagement and security during operation.
Applications
Aerospace Fastening
EN 4421:2007 studs are specifically designed for fastening critical aerospace components where strength, corrosion resistance, and weight reduction are essential. Common applications include:- Aircraft structural assemblies
- Engine mountings and components
- Aerospace mechanical systems requiring high-strength fasteners
- Components exposed to corrosive atmospheres or elevated mechanical stress
Maintenance and Repair
The standardized dimensions and coatings ensure these studs can be reliably used for repairs and retrofitting within aerospace systems, maintaining structural integrity and safety.Aerospace Manufacturing
Manufacturers of aerospace components use these studs for assembly lines requiring consistent, repeatable fastening solutions that meet rigorous quality and performance standards.
Related Standards
- EN 3311 – Titanium alloy TI-P64001 bars for machining, providing the raw material specification for stud manufacturing.
- EN 2424 – Marking of aerospace products, prescribing identification methods for traceability.
- EN 4458 – Technical specifications for studs with MJ threads made of the same titanium alloy and coating but detailing additional testing requirements.
- ISO 3353 & ISO 5855-2 – Aerospace standards governing threaded components, ensuring compatibility of threads used in EN 4421 studs.
- AMS 5604R – Specifications for corrosion-resistant steel used in the locking rings for enhanced durability.
Keywords: EN 4421:2007, aerospace studs, titanium alloy TI-P64001, MoS2 coating, serrated locking ring, aerospace fasteners, strength class 1100 MPa, corrosion-resistant steel, aerospace standard, aerospace components, high-strength studs, aerospace threading standards, aerospace manufacturing.
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Frequently Asked Questions
EN 4421:2007 is a standard published by the European Committee for Standardization (CEN). Its full title is "Aerospace series - Studs, in titanium alloy TI-P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel - Strength class: 1 100 MPa (at ambient temperature)". This standard covers: This standard specifies the characteristics of studs in TI P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel for aerospace applications. Strength class: 1 100 MPa )
This standard specifies the characteristics of studs in TI P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel for aerospace applications. Strength class: 1 100 MPa )
EN 4421:2007 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 4421:2007 has the following relationships with other standards: It is inter standard links to EN 3311:2023, EN 12513:2000, EN 2424:2008, EN 4458:2005, EN 840-6:2004+A1:2008, EN 4459:2005, EN 4460:2005. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN 4421:2007 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)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Luft- und Raumfahrt - Stiftschrauben, aus Titanlegierung TI-P64001, MoS2 beschichtet, mit Ringsicherung aus korrosionsbeständigem Stahl - Festigkeitsklasse: 1 100 MPa (bei Raumtemperatur)Série aérospatiale - Goujons, en alliage de titane TI-P64001, revêtus MoS2, avec bague de verrouillage dentelée, en acier résistant à la corrosion - Classe de résistance: 1 100 MPa (à température ambiante)Aerospace series - Studs, in titanium alloy TI-P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel - Strength class: 1 100 MPa (at ambient temperature)49.030.20Sorniki, vijaki, stebelni vijakiBolts, screws, studsICS:Ta slovenski standard je istoveten z:EN 4421:2007SIST EN 4421:2009en,de01-junij-2009SIST EN 4421:2009SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 4421
June 2007 ICS 49.030.20 English Version
Aerospace series - Studs, in titanium alloy TI-P64001, MoS2 coated, with serrated locking ring in corrosion resisting steel - Strength class: 1 100 MPa (at ambient temperature)
Série aérospatiale - Goujons, en alliage de titane TI-P64001, revêtus MoS2, avec bague de verrouillage dentelée, en acier résistant à la corrosion - Classe de résistance: 1 100 MPa (à température ambiante)
Luft- und Raumfahrt - Stiftschrauben, aus Titanlegierung TI-P64001, MoS2 beschichtet, mit Ringsicherung aus korrosionsbeständigem Stahl - Festigkeitsklasse: 1 100 MPa (bei Raumtemperatur) This European Standard was approved by CEN on 26 October 2005.
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 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 Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36
B-1050 Brussels © 2007 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 4421:2007: ESIST EN 4421:2009
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