SIST EN 2591-420:2009

Overview

SIST EN 2591-420:2009 is a European standard developed by CEN that defines test methods for assessing the mechanical strength of rear accessories used in aerospace electrical and optical connection elements. This standard focuses on evaluating the durability and robustness of rear accessories when subjected to various mechanical forces such as bending, tensile, and torsional stresses. SIST EN 2591-420:2009 complements EN 2591-100 and is essential for ensuring that aerospace connectors meet stringent safety and performance requirements.

Key Topics

• Scope and Purpose
  Specifies a standardized method for testing mechanical strength of rear accessories on connectors used in aerospace applications.

• Test Phases
  The standard outlines a detailed test sequence including:

  • Phase A: Bending Test
    Applies bending moments to test specimen accessories at a defined rate and duration.
  • Phase B: Tensile Test
    Applies tensile forces to evaluate the accessory’s resistance to pulling forces.
  • Phase C: Torsion Test
    Applies torsional moments to assess rotational stress resistance.
  • Phase D: Torque Test on Mating Thread
    Applies torque to the coupling nut to check for proper tightening and mechanical integrity.

• Preparation and Apparatus
  Calls for specific specimen mounting, locking, and use of fixtures simulating connector rear sections for realistic testing conditions. Equipment must apply and measure all test forces accurately.

• Acceptance Criteria
  Post-test inspections mandate zero deformation and no looseness between accessory and fixture. Untightening torque must meet specified values, ensuring reliable mechanical strength.

• Normative References
  Primarily used alongside EN 2591-100 and EN 2591-101 for comprehensive electrical and optical connection test methodologies and visual examinations.

Applications

SIST EN 2591-420:2009 is critical for aerospace manufacturers and suppliers involved in the design, production, and quality assurance of electrical and optical connector accessories. It helps to:

• Ensure Safety and Reliability
  By guaranteeing mechanical durability under mechanical loads experienced in aerospace environments.

• Support Product Certification
  Compliance with this standard facilitates certification processes and regulatory approvals for aerospace components.

• Enhance Connector Performance
  Testing for mechanical strength minimizes failure risks caused by stress during operation, installation, and maintenance.

• Guide Design Improvements
  Data obtained from these tests aid engineers in optimizing accessory designs for greater mechanical resilience.

Related Standards

• EN 2591-100: Aerospace series - Elements of electrical and optical connection - Test methods - Part 100: General
  Provides general test guidelines applicable alongside EN 2591-420.

• EN 2591-101: Aerospace series - Elements of electrical and optical connection - Test methods - Part 101: Visual examination
  Covers requirements for visual inspection after mechanical testing to ensure accessory integrity.

• Additional Aerospace Electrical Standards
  Other parts of the EN 2591 series addressing various aspects of aerospace connector testing and qualification.

Keywords: EN 2591-420, aerospace standard, mechanical strength testing, electrical connectors, optical connectors, rear accessories, bending test, tensile test, torsion test, aerospace connection elements, CEN standards, aerospace component testing, connector durability, aerospace quality assurance.