SIST EN 2799:2018

Overview

SIST EN 2799:2018 is a European Standard published by the Committee for European Normalization (CEN) that specifies the requirements for fluorocarbon rubber (FKM) with a low compression set and hardness of 90 IRHD, specifically tailored for aerospace applications. This standard defines the physical and chemical properties that ensure the material’s suitability for demanding aerospace environments, including exposure to air, hydrocarbons, synthetic oils, and fuels at elevated temperatures.

Key Topics

• Material Specification
  SIST EN 2799:2018 covers fluorocarbon elastomers (FKM) with a low compression set designed to operate reliably in aerospace conditions. The hardness is standardized at 90 IRHD, a measure of indentation hardness that ensures the material maintains its shape and resilience under compression.

• Performance Requirements
  The standard mandates specific mechanical properties such as tensile strength, elongation at break, tear strength, hardness, and resistance to ozone and low temperatures. Notably, a maximum compression set of 30% after 70 hours at 200 °C underscores the material’s ability to retain elasticity over long operational periods.

• Temperature Range

  • Continuous service operation: −20 °C to 225 °C
  • Intermittent service operation: −20 °C to 250 °C

• Chemical Resistance
  FKM rubber classified under EN 2799 withstands exposure to air, hydrocarbon, and synthetic oils, as well as fuels, making it ideal for aerospace sealing and insulation components.

• Testing and Qualification
  The standard references testing methods from ISO 1629, ISO 1817, and EN 3207 to verify properties such as hardness, density, tensile strength, elongation, compression set, resistance to fluids, and corrosion and adhesion on metals. The qualification tests are stringent, ensuring batch-to-batch consistency.

Applications

SIST EN 2799:2018 fluorocarbon rubber is used primarily in the aerospace industry for components that require high performance under harsh environmental conditions. Typical applications include:

• Sealing elements such as O-rings, gaskets, and seals in engines, fuel systems, and hydraulic units
• Protective coatings and insulation for aircraft systems exposed to oils and fuels
• Components in aerospace mechanisms where low compression set and high temperature resistance are critical for safety and longevity

The rubber’s resistance to chemical exposure and temperature fluctuations ensures reliable performance, reducing maintenance frequency and preventing leaks or mechanical failures.

Related Standards

• EN 3207 - Aerospace series: Rubber compounds - Technical specification
• ISO 1629 - Rubber and latices: Nomenclature standards defining rubber materials and classifications
• ISO 1817 - Rubber, vulcanized or thermoplastic: Determination of the effect of liquids
• Other ASD-STAN Standards - Aerospace material standards coordinated by the Aerospace and Defence Industries Association of Europe for harmonized quality and safety compliance

Summary

SIST EN 2799:2018 establishes a robust framework for specifying fluorocarbon rubber (FKM) elastomers with low compression set and specified hardness, optimized for aerospace applications involving exposure to aggressive chemicals and elevated temperatures. This standard ensures aerospace components meet stringent durability and safety requirements, supporting manufacturers and engineers in selecting consistent, high-performance FKM materials for critical applications.

Keywords: SIST EN 2799:2018, fluorocarbon rubber, FKM, aerospace sealing, low compression set, hardness 90 IRHD, aerospace standard, high temperature rubber, chemical resistance, rubber for aerospace, CEN standard, elastomer specifications.