SIST EN 3306:2001

Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315°C

This standard specifies the characteristics of screws, 100° coutersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, MoS2 lubricated. Classification: 1 100 MPa / 315 °C

Luft- und Raumfahrt - 100° Senkschrauben mit Flügelkreuzschlitz, Gewinde annähernd bis Kopf, aus Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1 100 MPa (bei Raumtemperatur)/315 °C

Diese Norm legt die Eigenschaften von 100 °C Senkschrauben mit Flügelkreuzschlitz, mit Gewinde annähernd bis Kopf, aus Titanlegierung, anodisiert, MoS2-geschmiert, fest. Klasse: 1 100 MPa / 315 °C

Série aérospatiale - Vis a tete fraisée 100° normale, a empreinte cruciforme déportée, filetées jusqu'a proximité de la tete, en alliage de titane, anodisées, lubrifiées MoS2 - Classification: 1 100 MPa (a température ambiante)/315 °C

La présente norme spécifie les caractéristiques des vis à tête fraisée 100° normale, à empreinte cruciforme déportée, filetées jusqu'à proximité de la tête, en alliage de titane, anodisées, lubrifiées MoS2. Classification: 1 100 MPa / 315 °C

Aerospace series - Screws, 100- countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315°C

General Information

• Status: Published
• Publication Date: 31-Dec-2000
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: SS SPL - Technical Board for the general field
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Jan-2001
• Due Date: 01-Jan-2001
• Completion Date: 01-Jan-2001
• Ref Project: EN 3306:1996 - Aerospace series - Screws, 100° countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315°C

Overview

EN 3306:1996 defines a specific aerospace fastener: 100° countersunk screws with a normal head, offset cruciform recess, threaded to the head, manufactured from titanium alloy, anodized, and MoS2 (molybdenum disulfide) lubricated. The published classification is "1 100 MPa (at ambient temperature)/315°C", indicating the documented performance class across ambient and elevated temperature conditions. This standard is part of the CEN aerospace series and is intended to ensure consistent characteristics for critical lightweight fasteners used in aircraft structures and systems.

Key topics and requirements

• Head geometry: 100° countersunk, normal head form for flush mounting in aerodynamic/structural surfaces.
• Recess type: Offset cruciform (cross) recess designed for specific driver engagement and torque control.
• Threading: Threads extend to the head ("threaded to head"), affecting engagement length and assembly design.
• Material: Titanium alloy - chosen for high strength-to-weight ratio and corrosion resistance in aerospace environments.
• Surface treatment: Anodized finish to improve corrosion resistance and surface durability.
• Lubrication: MoS2 (molybdenum disulfide) application for controlled friction during assembly and consistent torque-tension behavior.
• Classification/performance: Stated as 1 100 MPa (at ambient temperature)/315°C - the standard’s classification that guides allowable use temperatures and mechanical performance expectations.

Note: EN 3306 specifies characteristics and classification rather than detailed dimensional tables or installation torque values; users should consult the full standard text for exact tolerances and inspections.

Applications

• Structural and non-structural fastenings in aerospace assemblies where:
  • Low weight and high strength are essential
  • Flush-mounted countersunk heads are required for aerodynamic surfaces
  • Corrosion resistance and controlled assembly friction are needed (e.g., airframes, panels, interior fittings)
• Environments with elevated-service temperatures up to the stated classification limit

Who uses this standard

• Aerospace design and structural engineers specifying fasteners
• Procurement and quality assurance teams verifying supplier conformity
• Fastener manufacturers producing titanium countersunk screws
• Maintenance, repair, and overhaul (MRO) organizations ensuring correct replacement parts
• Test laboratories performing fastener qualification and acceptance

Related standards

• Other EN and aerospace fastener standards covering head forms, thread classes, material specifications, and torque/assembly practices. For complete implementation, pair EN 3306 with applicable titanium alloy material standards and assembly/installation guidance from aircraft manufacturers.

Keywords: EN 3306:1996, aerospace screws, 100° countersunk screws, titanium screws, anodized fasteners, MoS2 lubricated, offset cruciform recess, threaded-to-head, aerospace fasteners.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aerospace series - Screws, 100- countersunk normal head, offset cruciform recess, threaded to head, in titanium alloy, anodized, MoS2 lubricated - Classification: 1 100 MPa (at ambient temperature)/315°CLuft- und Raumfahrt - 100° Senkschrauben mit Flügelkreuzschlitz, Gewinde annähernd bis Kopf, aus Titanlegierung, anodisiert, MoS2-geschmiert - Klasse: 1 100 MPa (bei Raumtemperatur)/315 °CSérie aérospatiale - Vis a tete fraisée 100° normale, a empreinte cruciforme déportée, filetées jusqu'a proximité de la tete, en alliage de tita
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