SIST EN 3566:2004

Overview

SIST EN 3566:2004 is a European Standard published by CEN that defines the specifications for adaptors with lockring used in aerospace pipe couplings. These adaptors are made from titanium alloy and designed for pipe couplings at an angle of 8°30'. The standard ensures the compatibility, reliability, and safety of these components when installed in a boss for aerospace fluid systems.

Key operating parameters include a nominal pressure rating of up to 28,000 kPa and a wide temperature range from -55 °C to +135 °C, addressing the demanding environmental conditions found in aerospace applications. This standard supports manufacturers and engineers by providing crucial technical requirements for material, dimensions, surface treatment, and performance of these adaptors.

Key Topics

• Material Requirements
  Adaptors must be manufactured using titanium alloy compliant with EN 3311 or EN 3314, ensuring high strength-to-weight ratio and corrosion resistance suitable for aerospace environments.

• Dimensional Specifications
  Detailed configuration and dimensional criteria are specified, including thread sizes, port ends, and lockring interfaces to ensure interchangeability and system integrity. Dimensions are provided before surface treatments, maintaining precision in design.

• Surface Treatment and Lubrication
  Surfaces are lubricated per EN 2491 standards, except the flow hole. Lubrication is applied after abrasive blasting to promote adhesion, with a film thickness between 0.005 mm and 0.013 mm. Alternatively, anodizing per AMS 2488D (Type 2) may be applied to enhance surface durability and corrosion resistance.

• Performance Ratings
  The standard specifies that adaptors must withstand nominal pressures up to 28,000 kPa and operate reliably across temperature extremes from -55 °C to +135 °C, aligning with aerospace system demands.

• Marking and Identification
  Marking is required following EN 2424, style G6, which provides traceability and compliance validation across supply chains.

Applications

SIST EN 3566:2004 adaptors with lockring in titanium alloy are primarily used in aerospace fluid systems, including:

• Fuel Systems
  Providing secure, leak-free connections in aircraft fuel lines that require high strength, corrosion resistance, and lightweight components.

• Hydraulic Systems
  Ensuring consistent performance under high pressure and temperature variations in aircraft hydraulic circuits.

• Environmental Control Systems
  Facilitating fluid transport where temperature changes are significant, requiring materials and components that maintain integrity over a wide temperature range.

• General Aerospace Pipe Installations
  Adaptors complying with SIST EN 3566:2004 help achieve standardization in installation methods, reducing risks in pipe coupling failures and enhancing system maintenance efficiency.

Related Standards

SIST EN 3566:2004 references and aligns with several other standards critical for aerospace fluid system components:

• ISO 5855-3 – Aerospace MJ threads, limits, and dimensions for fittings
• EN 2424 – Aerospace product marking requirements
• EN 2491 – Molybdenum disulphide dry lubricants for aerospace coatings
• EN 2602 to EN 2604 – Dimensions and interface requirements for metric-size unions with locking rings
• EN 3079 – Technical specifications for pipe coupling adaptors up to 28,000 kPa
• EN 3311 / EN 3314 – Specifications for titanium alloy bars used in aerospace machining
• AMS 2488D – Anodic treatment of titanium and titanium alloys

Integrating these standards ensures a comprehensive approach to design, manufacturing, installation, and maintenance for aerospace pipe coupling systems.

Keywords: SIST EN 3566:2004, aerospace pipe coupling, titanium alloy adaptors, lockring, high-pressure adaptors, aerospace fluid systems, aerospace connectors, pipe coupling dimensions, aerospace material standards, aerospace temperature range, aerospace hydraulic fittings, titanium aerospace components.