SIST EN 4509:2026

• Abstract:

  This document specifies the characteristics of screws, 100° countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, with aluminium pigmented coating, metric series.; Classification: 1 100 MPa /315 °C .

• Status: Published
• Public Enquiry End Date: 24-Dec-2024
• Publication Date: 29-Sep-2026
• ICS: 49.025.20 - Aluminium
• ICS: 49.025.30 - Titanium
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 29-Sep-2026
• Due Date: 04-Dec-2026
• Completion Date: 30-Sep-2026
• Ref Project: EN 4509:2026 - Aerospace series - Screw, 100° countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, with aluminium pigmented coating, metric series - Classification: 1 100 MPa (at ambient temperature)/315 °C

• Refers: SIST EN 2424:2008 - Aerospace series - Marking of aerospace products
• Effective Date: 30-Sep-2026
• Refers: SIST EN 4473:2025 - Aerospace series - Aluminium pigmented organic coatings for fasteners - Technical specification
• Effective Date: 30-Sep-2026
• Revises: SIST EN 4509:2009 - Aerospace series - Screws, 100 countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, with aluminium pigmented coating, metric series - Classification: 1 100 MPa (at ambient temperature) / 315 °C
• Effective Date: 23-Apr-2024

SIST EN 4509:2026 is the Slovenian adoption of EN 4509:2026 for aerospace screws. It specifies a 100° countersunk normal head screw with an offset cruciform recess, threaded to the head, made in titanium alloy, anodized, and finished with an aluminium pigmented coating, in metric series. The document is used to specify the product, check its characteristics, and control designation, marking, manufacturer approval, and qualification.

What does SIST EN 4509:2026 specify?

SIST EN 4509:2026 specifies the characteristics of one defined aerospace screw type and the rules needed to identify and qualify it. In practice, it gives the product description, the required dimensions and materials, the surface treatment, the designation system, the marking, and the technical specification for procurement and qualification.

The document is organized as follows:

• Clause 1 - Scope
• Clause 2 - Normative references
• Clause 3 - Terms and definitions
• Clause 4 - Required characteristics
• Clause 5 - Designation
• Clause 6 - Marking
• Clause 7 - Technical specification
• Bibliography

For a buyer or engineer, this structure matters because it separates what the screw is, how it is described, how it is marked, and what must be done to approve and qualify it.

What are the key requirements of SIST EN 4509:2026?

SIST EN 4509:2026 sets out the product definition in Clause 4 and then ties it to designation, marking, and qualification in Clauses 5 to 7. The main requirements are practical: select the right size and drive code, use the right titanium material, apply the required surface treatment, and document manufacturer approval and qualification.

Configuration, dimensions, and mass

Clause 4.1 states that the configuration, dimensions, and mass shall follow Figure 1 and Table 1. Dimensions and tolerances are given in millimetres and apply after coating. That matters because the finished screw must still meet the specified geometry after surface treatment, so inspection has to be based on the coated part.

Clause 4.1 also leaves details of form that are not stated to the manufacturer’s discretion. In practice, that means the standard fixes the critical features while allowing some freedom where the document is silent.

Tolerances and thread-related features

Clause 4.2 requires tolerances of form and position to follow ISO 7913. Clause 4 and the figure also link the thread and thread-runout features to ISO 3353-1 and the MJ thread system in ISO 5855-2. For users, this means the screw is not just a shape description - it is tied to aerospace thread geometry and positional accuracy rules.

Materials and surface treatment

Clause 4.3 requires materials in accordance with TR 3775 for titanium alloy, strength class 1 100 MPa. Clause 4.4 requires surface treatments in accordance with EN 4473. Lubrication with cetyl alcohol is permitted under EN 6117 or SAE AS87132, and anodizing may be omitted if the parts are blasted before surface treatment. That combination matters because the screw’s mechanical performance, corrosion protection, and assembly behavior all depend on the specified material and finish.

Designation and marking

Clause 5 says the designation shall follow Table 1 and Table 2. The designation combines the diameter code, length code, and drive code, which makes ordering and traceability consistent across suppliers.

Clause 6 requires marking in accordance with EN 2424 and Figure 1, with the marking shown as indented. Table 3 gives the marking format by diameter code and style. In practice, this is what manufacturers and inspectors use to confirm that the part identification matches the specified screw type.

Technical specification, manufacturer approval, and qualification

Clause 7 requires the technical specification to follow ISO 9152. It also requires the manufacturer to be an approved production organization for aerospace products and to have a quality management system, for example EN 9100 or an equivalent aerospace-accepted and established system. Qualification of screws shall follow an aerospace standard product qualification procedure, for example EN 9133 or an equivalent procedure, and be documented according to the specified tests unless the customer and supplier agree otherwise. This is the part that matters for sourcing and quality control.

What terms does SIST EN 4509:2026 define?

SIST EN 4509:2026 uses a few key terms and codes that are important for selection and ordering.

• Classification 1 100 MPa /315 °C - the document’s strength and temperature classification for this screw type.
• Minimum tensile strength - the strength level of the material at ambient temperature.
• Maximum temperature - the highest temperature the screw can withstand without continuous change in its original characteristics after return to ambient temperature; the coating determines this limit.
• Offset cruciform recess - the internal drive recess used in the screw head.
• Diameter code - the code used in Table 1 to identify the nominal thread diameter.
• Length code - the code used in Table 1 to identify the screw length.
• Drive code - the code used in Table 2 to identify the drive variant.

Who uses SIST EN 4509:2026?

SIST EN 4509:2026 is used by aerospace design engineers, procurement teams, fastener manufacturers, and quality or inspection personnel. Designers use it to choose a screw with the correct head, drive, thread, material, and finish. Buyers and suppliers use it to write purchase descriptions and confirm that the delivered part matches the required designation, marking, and qualification path.

Which standards are used with SIST EN 4509:2026?

SIST EN 4509:2026 relies on several other standards to define the supporting requirements:

Standard	What it contributes
EN 2424	Marking of aerospace products
EN 4473	Aluminium pigmented organic coatings for fasteners
EN 6117	Lubrication of fasteners with cetyl alcohol
ISO 3353-1	Lead and runout threads for rolled external threads
ISO 5855-2	Limit dimensions for MJ threads on bolts and nuts
ISO 7913	Tolerances of form and position for bolts and screws
ISO 9152	Procurement specification for titanium alloy MJ-thread bolts and screws, strength class 1 100 MPa
ISO 14275	Offset cruciform internal drive, ribbed, metric series
ISO 14276	Offset cruciform internal drive, metric series
TR 3775	Materials for bolts and pins
SAE AS87132	Cetyl alcohol lubricant for fasteners

Clause 7 also points to EN 9100 as an example of a suitable quality management system and EN 9133 as an example of a qualification procedure for aerospace standard products.

What does the SIST EN 4509:2026 document contain?

SIST EN 4509:2026 contains Figure 1, which shows the screw configuration, and Tables 1 to 3, which cover dimensions and mass, drive codes, and marking. Table 1 is the main ordering and inspection table because it links diameter and length codes to the permitted sizes and approximate mass. Table 2 supports the designation by linking the drive variant to its code. Table 3 supports traceability by defining how the screw is marked. Clause 7 adds the approval and qualification steps needed for aerospace production and supply.

SLOVENSKI STANDARD
01-november-2026
Aeronavtika - Vijak, s 100° ugrezno glavo, križno zarezo, z navojem do glave, iz
titanove zlitine, anodiziran, z aluminijevim pigmentiranim premazom, metrična
serija - Klasifikacija: 1100 MPa (pri temperaturi okolice)/315 °C
Aerospace series - Screw, 100° countersunk normal head, offset cruciform recess,
threaded to head, in titanium alloy, anodized, with aluminium pigmented coating, metric
series - Classification: 1 100 MPa (at ambient temperature)/315 °C
Luft- und Raumfahrt - 100° Senkschraube, mit Flügelkreuzschlitz, Gewinde annähernd
bis Kopf, aus Titanlegierung, anodisiert, mit Aluminium pigmentierter Beschichtung,
metrische Reihe - Klasse: 1 100 MPa (bei Raumtemperatur)/315 °C
Série aérospatiale - Vis à tête fraisée 100° normale, à empreinte cruciforme déportée,
filetées jusqu'à proximité de la tête, en alliage de titane, anodisées, avec revêtement
alumino-organique, série métrique - Classification : 1 100 MPa (à température
ambiante)/315 °C
Ta slovenski standard je istoveten z: EN 4509:2026
ICS:
49.025.20 Aluminij Aluminium
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 4509
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2026
EUROPÄISCHE NORM
ICS 49.030.20
English Version
Aerospace series - Screw, 100° countersunk normal head,
offset cruciform recess, threaded to head, in titanium alloy,
anodized, with aluminium pigmented coating, metric
series - Classification: 1 100 MPa (at ambient
temperature)/315 °C
Série aérospatiale - Vis à tête fraisée 100° normale, à Luft- und Raumfahrt - 100° Senkschraube, mit
empreinte cruciforme déportée, filetée jusqu'à Flügelkreuzschlitz, Gewinde annähernd bis Kopf, aus
proximité de la tête, en alliage de titane, anodisée, avec Titanlegierung, anodisiert, mit Aluminium
revêtement alumino-organique, série métrique - pigmentierter Beschichtung, metrische Reihe - Klasse:
Classification : 1 100 MPa (à température 1 100 MPa (bei Raumtemperatur)/315 °C
ambiante)/315 °C
This European Standard was approved by CEN on 3 August 2026.

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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4509:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Required characteristics . 5
4.1 Configuration — Dimensions Mass . 5
4.2 Tolerances of form and position . 5
4.3 Materials . 5
4.4 Surface treatments . 5
5 Designation . 8
6 Marking . 8
7 Technical specification . 8
7.1 General. 8
7.2 Approval of manufacturers . 8
7.3 Qualification of screws . 9
Bibliography . 10

European foreword
This document (EN 4509:2026) 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 March 2027, and conflicting national standards shall
be withdrawn at the latest by March 2027.
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.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can
...