SIST EN 4851:2022

Aerospace series - Screw, 100° countersunk normal head, Spiral Drive Recess, coarse tolerance normal shank, long thread, in alloy steel, cadmium plated - Classification: 1 100 MPa (at ambient temperature)/235 °C

This document specifies the characteristics of externally threaded fasteners, 100° countersunk normal head, Spiral Drive Recess, coarse tolerance normal shank, long thread, in alloy steel, cadmium plated, for aerospace applications.
Classification: 1 100 MPa /235 °C .

Luft- und Raumfahrt - 100° Senkschraube, Spiral-Antrieb, grobe Schafttoleranz, langes Gewinde, aus legiertem Stahl, kadmiert - Klasse: 1 100 MPa (bei Raumtemperatur)/235 °C

Dieses Dokument legt die Eigenschaften von Verbindungselementen mit Außengewinde, 100°-Senkkopfschraube, Spiral-Antrieb, grobe Schafttoleranz, langes Gewinde, aus legiertem Stahl, kadmiert, für Luft- und Raumfahrtanwendungen fest.
Klasse: 1 100 MPa /235 °C .

Série aérospatiale - Vis à tête fraisée normale 100°, empreinte en spirale, tige normale à tolérance large, filetage long, en acier allié, cadmiée - Classification : 1 100 MPa (à température ambiante)/235 °C

Le présent document spécifie les caractéristiques des éléments de fixation à filetage extérieur, à tête fraisée normale 100°, empreinte en spirale, tige normale à tolérance large, filetage long, en acier allié, cadmiés, pour les applications aérospatiales.
Classification : 1 100 MPa/235 °C.

Aeronavtika - Vijak, 100° ugrezna glava, spiralna vdolbina, široka toleranca, dolg navoj, iz legiranega jekla, kadmiran - Klasifikacija: 1100 MPa (pri temperaturi okolice)/235 °C

Ta dokument določa značilnosti zunanjih navojnih veznih elementov – 100° ugrezna glava, spiralna vdolbina, široka toleranca, dolg navoj, iz legiranega jekla, kadmiranih – za uporabo v aeronavtiki.
Klasifikacija: 1100 MPa/235 °C.

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 4851:2022 - Aerospace series - Screw, 100° countersunk normal head, Spiral Drive Recess, coarse tolerance normal shank, long thread, in alloy steel, cadmium plated - Classification: 1 100 MPa (at ambient temperature)/235 °C

Overview

SIST EN 4851:2022 is a European standard published by CEN that specifies the characteristics of aerospace-grade externally threaded fasteners. These screws feature a 100° countersunk normal head and a Spiral Drive Recess, designed for high-performance aerospace applications. Manufactured from alloy steel and cadmium plated for corrosion resistance, the screws conform to a coarse tolerance normal shank with a long thread profile. This standard covers screws classified for strength up to 1100 MPa at ambient temperature and capable of withstanding temperatures up to 235 °C without degradation of mechanical properties.

Key Features

• Thread Type: External, coarse pitch with long thread length in accordance with ISO 3353-1
• Head Style: 100° countersunk normal head ensuring flush mounting and aerodynamic surfaces
• Drive System: Spiral Drive Recess (MORTORQ® system), providing enhanced torque transfer and reduced cam-out risk
• Material: Alloy steel selected for strength classes between 1100-1250 MPa, meeting EN 2137 and EN 3514 requirements
• Surface Treatment: Cadmium plating compliant with EN 2133, offering robust corrosion protection; includes options for hexavalent chromium and non-chromium (VI) passivation coatings
• Dimensional Tolerances: Coarse tolerance normal shank and defined tolerances of form and position according to ISO 7913
• Marking: Indented marking per EN 2424 standard ensures traceability and compliance verification

Practical Applications

This standard is specifically tailored to meet the rigorous demands of aerospace manufacturing and maintenance, where fastener reliability is critical. Applications include:

• Aircraft Assembly: Fastening structural components requiring flush surface integration for aerodynamic performance
• Spacecraft Construction: Providing reliable fastening solutions that withstand extreme temperature fluctuations
• Defense Equipment Manufacturing: Ensuring high-strength fasteners for military-grade aerospace hardware
• Maintenance and Repair Operations: Standardized screw specifications enable efficient replacement with guaranteed performance
• Aerospace Component Suppliers: Assisting manufacturers in producing interchangeable parts compliant with uniform quality standards

Adherence to EN 4851 enables manufacturers and maintenance providers to maintain industry safety standards and compatibility across international aerospace sectors.

Related Standards

SIST EN 4851:2022 references and aligns with several key aerospace and fastener standards, including:

• EN 2133: Guidelines on cadmium plating processes for steels with tensile strength ≤ 1450 MPa
• EN 2137 & EN 3514: Specifications for alloy steel bars used in fastener production meeting strength requirements
• EN 4609: Definition and technical requirements for Spiral Drive Recess in aerospace threaded fasteners
• ISO 3353-1: Standards for rolled external threads, critical for thread consistency and strength
• ISO 7913: Tolerances of form and position for bolts and screws ensuring precise mechanical fit
• EN 2424: Marking requirements for aerospace products facilitating product traceability and quality control
• ISO 7689: Procurement specifications covering bolts with MJ threads in high-strength alloy steel
• EN 9100 & EN 9133: Aerospace quality management and qualification procedures ensuring manufacturer reliability and product certification

By integrating EN 4851 into the procurement and manufacturing process, aerospace organizations benefit from improved fastener performance, uniformity, and regulatory compliance essential to the aviation and space industries.

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Keywords: EN 4851, aerospace fasteners, 100° countersunk screw, Spiral Drive Recess, alloy steel screws, cadmium plated screws, aerospace threaded fasteners, aviation fasteners, aerospace fastener standards, high-strength screws, aerospace manufacturing, aerospace quality standards, aerospace bolt specification

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2022
Aeronavtika - Vijak, 100° ugrezna glava, spiralna vdolbina, široka toleranca, dolg
navoj, iz legiranega jekla, kadmiran - Klasifikacija: 1100 MPa (pri temperaturi
okolice)/235 °C
Aerospace series - Screw, 100° countersunk normal head, Spiral Drive Recess, coarse
tolerance normal shank, long thread, in alloy steel, cadmium plated - Classification: 1
100 MPa (at ambient temperature)/235 °C
Luft- und Raumfahrt - 100° Senkschraube, Spiral-Antrieb, grobe Schafttoleranz, langes
Gewinde, aus legiertem Stahl, kadmiert - Klasse: 1 100 MPa (bei Raumtemperatur)/235
°C
Série aérospatiale - Vis à tête fraisée normale 100°, empreinte en spirale, tige normale à
tolérance large, filetage long, en acier allié, cadmiée - Classification : 1 100 MPa (à
température ambiante)/235 °C
Ta slovenski standard je istoveten z: EN 4851:2022
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 4851
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2022
EUROPÄISCHE NORM
ICS 49.030.20
English Version
Aerospace series - Screw, 100° countersunk normal head,
Spiral Drive Recess, coarse tolerance normal shank, long
thread, in alloy steel, cadmium plated - Classification: 1
100 MPa (at ambient temperature)/235 °C
Série aérospatiale - Vis à tête fraisée normale 100°, Luft- und Raumfahrt - 100° Senkschraube, Spiral-
empreinte en spirale, tige normale à tolérance large, Antrieb, grobe Schafttoleranz, langes Gewinde, aus
filetage long, en acier allié, cadmiée - Classification : 1 legiertem Stahl, kadmiert - Klasse: 1 100 MPa (bei
100 MPa (à température ambiante)/235 °C Raumtemperatur)/235 °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 4851:2022 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 . 9
6 Marking . 9
7 Technical specification . 9
Bibliography. 10

European foreword
This document (EN 4851:2022) 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 patent „Spiral Drive System for Threaded
Fasteners“ EP1025370B1.
ASD-STAN takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured ASD-STAN that he/she is willing to negotiate licences under
reasonable and non-discriminatory terms and conditions with applicants throughout the world. In this
respect, the statement of the holder of this patent right is registered with ASD-STAN. Information may be
obtained from:
Phillips Screw Company
301 Edgewater Drive, Suite 320
Wakefield, Massachusetts 01880
USA
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights other than those identified above. ASD-STAN shall not be held responsible for identifying
any
...