EN 2568:2019

Overview

EN 2568:2019 is a European standard developed by CEN that specifies the properties and technical requirements for fluorocarbon rubber (FKM) with a hardness of 90 IRHD, aimed primarily at aerospace applications. This standard ensures that FKM materials meet stringent aerospace industry demands for performance, reliability, and safety at elevated temperatures. The document is essential for manufacturers, suppliers, and engineers involved in aerospace component design and production where high-performance elastomers are required.

Key Topics

• Material Specification: Defines fluorocarbon rubber (FKM) with a standardized hardness level of 90 IRHD, indicating a medium to high hardness suitable for durable aerospace seals and components.
• Temperature Resistance: Suitable for continuous service temperatures ranging from -20 °C to 225 °C, and intermittent exposure up to 250 °C.
• Chemical Resistance: FKM is specified for applications requiring resistance to air, hydrocarbons, synthetic oils, and fuels under elevated temperature conditions.
• Mechanical Properties:
  • Minimum tensile strength of 11 MPa
  • Minimum elongation at break of 100%
  • Maximum compression set of 40% after 24 hours at 200 °C to meet long-term sealing performance
• Testing and Qualification:
  • Includes tests for hardness, density, tensile strength, elongation, resistance to low temperatures, ozone resistance, and corrosion/adhesion on metals.
  • Specifies batch acceptance and qualification requirements in alignment with aerospace industry standards.
• Designations and Compliance: The standard includes detailed guidance on designation format and references other relevant aerospace rubber standards such as EN 3207 for technical specifications.

Applications

EN 2568:2019 is targeted at aerospace industry applications demanding high-performance elastomeric materials with excellent durability under harsh environmental conditions. Typical uses include:

• Seals and gaskets in aircraft hydraulic and fuel systems requiring fuel and oil resistance.
• Components exposed to elevated temperatures and fluctuating thermal cycles without compromising mechanical integrity.
• Aerospace hardware where ozone and weather resistance are critical.
• Other applications in aerospace vehicles that require strong adhesion to metal surfaces without corrosion risks.

The specification helps aerospace manufacturers ensure that FKM materials used in critical sealing and insulating parts comply with rigorous European regulatory and industry requirements.

Related Standards

EN 2568:2019 integrates with and references several key rubber and aerospace material standards to provide a comprehensive framework:

• EN 3207: Aerospace series - Rubber compounds - Technical specification. This standard provides additional specifications for aerospace rubber compounds complementing EN 2568.
• ISO 1629: Rubber and latices - Nomenclature. Defines terminology used in the rubber industry, including the chemical symbol for FKM.
• ISO 1817: Rubber, vulcanized - Determination of the effect of liquids. Specifies test methods for evaluating resistance to liquids, which is a critical property tested under EN 2568.
• ASD-STAN: Aerospace and Defence Industries Standardization body responsible for preparing this and other aerospace-related standards.

Summary

EN 2568:2019 sets a precise standard for fluorocarbon rubber (FKM) hardness 90 IRHD tailored to aerospace needs. Its detailed requirements for mechanical properties, thermal and chemical resistance alongside rigorous testing procedures ensure material reliability in demanding aerospace environments. By adhering to EN 2568, aerospace manufacturers and suppliers can guarantee high-quality FKM elastomer components, enhancing performance, safety, and regulatory compliance.

Keywords: EN 2568:2019, fluorocarbon rubber, FKM, hardness 90 IRHD, aerospace elastomer, aerospace seals, rubber standards, aerospace materials, high temperature rubber, chemical resistant rubber, aerospace rubber specification, CEN standards for aerospace.