SIST EN 4844:2022

Aerospace series - Screws, 100° countersunk normal head, Spiral Drive Recess, threaded to head, in heat and corrosion resisting steel, passivated - Classification : 1 100 MPa (at ambient temperature) / 425 °C

This document specifies the characteristics of externally threaded fasteners, 100° countersunk normal
head, Spiral Drive Recess, threaded to head, in heat and corrosion resisting steel, passivated, for
aerospace applications.

Luft und Raumfahrt - 100° Senkschrauben mit Spiral Antrieb, Gewinde annähernd bis Kopf, aus korrosionsbeständigem und hochwarmfestem Stahl, passiviert - Klasse: 1 100 MPa (bei Raumtemperatur)/425 °C

Dieses Dokument legt die Eigenschaften von Verbindungselementen mit Außengewinde, 100° Senkkopfschraube, Spiral-Antrieb, Gewinde annähernd bis Kopf, aus korrosionsbeständigem und hochwarmfestem Stahl, passiviert, für Luft- und Raumfahrtanwendungen fest.

Série aérospatiale - Vis à tête fraisée normale 100°, empreinte en spirale, filetée jusqu'à proximité de la tête, en acier résistant à chaud et à la corrosion, passivée - Classification : 1 100 MPa (à température ambiante)/425 °C

Aeronavtika - Vijaki, 100° ugrezna glava, spiralna vdolbina, z navojem do glave, iz toplotno in korozijsko odpornega jekla, pasivirani - Klasifikacija: 1100 MPa (pri temperaturi okolice)/425 °C

Ta dokument določa značilnosti zunanjih navojnih veznih elementov – 100° ugrezna glava, spiralna vdolbina, z navojem do glave, iz toplotno in korozijsko odpornega jekla, pasiviranih – za uporabo v aeronavtiki.

General Information

• Status: Published
• Publication Date: 05-Apr-2022
• ICS: 49.025.10 - Steels
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 30-Mar-2022
• Due Date: 04-Jun-2022
• Completion Date: 06-Apr-2022
• Ref Project: EN 4844:2022 - Aerospace series - Screws, 100° countersunk normal head, Spiral Drive Recess, threaded to head, in heat and corrosion resisting steel, passivated - Classification : 1 100 MPa (at ambient temperature) / 425 °C

Overview

EN 4844:2022 defines requirements for aerospace externally threaded fasteners: 100° countersunk normal head screws with Spiral Drive Recess, threaded to the head, manufactured in heat- and corrosion-resisting steel and passivated. The standard is published by CEN/ASD-STAN and classifies these fasteners as 1 100 MPa (ambient) with a maximum use temperature of 425 °C. It covers configuration, tolerances, materials, surface treatment, designation and marking for aerospace applications.

Key Topics

• Configuration and dimensions: Head form, thread and recess geometry are specified; dimensions and tolerances are given in millimetres and apply after surface treatment.
• Surface finish: Specified roughness values include Ramax = 0.8 µm for bearing surfaces (underhead face, thread) and Ramax = 3.2 µm for other surfaces. Sharp edges shall be broken (0.1 to 0.4 mm).
• Material and strength: Materials are to conform to EN 3761, which addresses heat-resisting alloy bar for forged fasteners in the relevant strength range (1 100 MPa ≤ R ≤ 1 300 MPa). The minimum tensile strength at ambient temperature is 1 100 MPa.
• Surface treatment: Passivation and any decontamination requirements follow EN 2516.
• Drive system and intellectual property: Spiral Drive Recess geometry and technical requirements are referenced to EN 4609. The document notes a claimed patent (Spiral Drive System for Threaded Fasteners) and that licensing discussions are managed by the patent holder.
• Quality and qualification: Manufacturer approval and product qualification follow aerospace quality procedures (e.g., EN 9100 and EN 9133) and procurement specifications such as ISO 8168.

Applications

EN 4844:2022 fasteners are intended for aerospace and defence structures and components where:

• High strength and elevated temperature resistance are required (rated to 1 100 MPa and service to 425 °C).
• Corrosion resistance and passivated surfaces are essential for longevity and safety.
• Low-profile countersunk fastening is needed to provide flush surfaces in airframes, engine components and structural assemblies.

Practical benefits include consistent interchangeability, traceable marking, and harmonized procurement criteria for suppliers and manufacturers within the CEN member states.

Related Standards

• EN 4609 - Spiral drive recesses: geometrical definition and technical requirements
• EN 3761 - Heat resisting alloy for forged fasteners (materials)
• EN 2516 - Passivation of corrosion resisting steels
• ISO 3353-1, ISO 5855-2, ISO 7913, ISO 8168 - Thread, dimensional and procurement references
• EN 2424, EN 9100, EN 9133 - Marking and quality/qualification frameworks

For design, procurement and manufacturing, refer to EN 4844:2022 together with the cited normative documents to ensure compliance with configuration, marking and technical specification requirements.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2022
Aeronavtika - Vijaki, 100° ugrezna glava, spiralna vdolbina, z navojem do glave, iz
toplotno in korozijsko odpornega jekla, pasivirani - Klasifikacija: 1100 MPa (pri
temperaturi okolice)/425 °C
Aerospace series - Screws, 100° countersunk normal head, Spiral Drive Recess,
threaded to head, in heat and corrosion resisting steel, passivated - Classification : 1 100
MPa (at ambient temperature) / 425 °C
Luft und Raumfahrt - 100° Senkschrauben mit Spiral Antrieb, Gewinde annähernd bis
Kopf, aus korrosionsbeständigem und hochwarmfestem Stahl, passiviert - Klasse: 1 100
MPa (bei Raumtemperatur)/425 °C
Série aérospatiale - Vis à tête fraisée normale 100°, empreinte en spirale, filetée jusqu'à
proximité de la tête, en acier résistant à chaud et à la corrosion, passivée - Classification
: 1 100 MPa (à température ambiante)/425 °C
Ta slovenski standard je istoveten z: EN 4844:2022
ICS:
49.025.10 Jekla Steels
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 4844
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2022
EUROPÄISCHE NORM
ICS 49.030.20
English Version
Aerospace series - Screws, 100° countersunk normal head,
Spiral Drive Recess, threaded to head, in heat and
corrosion resisting steel, passivated - Classification : 1 100
MPa (at ambient temperature) / 425 °C
Série aérospatiale - Vis à tête fraisée normale 100°, Luft und Raumfahrt - 100° Senkschrauben mit Spiral
empreinte en spirale, filetée jusqu'à proximité de la Antrieb, Gewinde annähernd bis Kopf, aus
tête, en acier résistant à chaud et à la corrosion, korrosionsbeständigem und hochwarmfestem Stahl,
passivée - Classification : 1 100 MPa (à température passiviert - Klasse: 1 100 MPa (bei
ambiante)/425 °C Raumtemperatur)/425 °C
This European Standard was approved by CEN on 10 January 2022.

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, Turkey 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
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4844:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Requirements . 6
4.1 Configuration — Dimensions — Masses . 6
4.2 Tolerances of form and position . 8
4.3 Materials . 8
4.4 Surface treatment . 8
5 Designation . 8
6 Marking . 8
7 Technical specification . 9
Bibliography. 10

European foreword
This document (EN 4844:2022) 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 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 September 2022, and conflicting national standards shall
be withdrawn at the latest by September 2022.
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.
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.
Introduction
Aerospace and Defence Standardisation (ASD-STAN) draws attention to the fact that it is claimed that
compliance with this document may involve the use of a pa
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