EN 2591-423:2005

Overview

EN 2591-423:2005 is a European Standard developed within the aerospace series that outlines a test method for assessing the rear accessories thread strength of electrical and optical connectors. This standard, issued by CEN and approved in 2005, specifies a rigorous procedure to verify the mechanical robustness of connector accessory threads under torque stress conditions. It is intended for use in conjunction with EN 2591-100, which covers general test methods for aerospace electrical and optical connection elements.

Ensuring the strength and reliability of accessory threads in aerospace connectors is critical for maintaining secure and durable electrical or optical connections in demanding operational environments. This standard provides a consistent, repeatable method for manufacturers, testers, and certification bodies to assess thread durability, helping to improve safety and performance across aerospace applications.

Key Topics

• Scope and Purpose
  EN 2591-423 focuses specifically on the ability of accessory threads-the threaded parts at the rear of connectors-to withstand mechanical stresses such as torque. This testing ensures threads do not deform or fail under operational loads.

• Test Setup and Specimen Preparation
  Specimens are mounted in a rigid panel simulating actual service conditions, preventing deformation of the test fixture. Connectors are mated properly as they would be in operational environments, reflecting realistic mechanical constraints.

• Test Apparatus
  The main tool used is a calibrated torque wrench, applied as per the standard’s instructions. The wrench lever arm and torque application point are precisely arranged to ensure consistent force distribution on the accessory thread.

• Testing Procedure
  A torque load is steadily applied to the accessory end of the plug at approximately 1 Newton-meter per second until the specified torque is reached. This load is maintained for one minute before removal.

• Assessment Criteria
  After torque application, specimens undergo a visual examination in accordance with EN 2591-101-looking for any deformation or damage to components. The absence of deformation confirms thread strength compliance.

Applications

This standard is essential for quality assurance during manufacturing, as well as for incoming inspection and certification of aerospace electrical and optical connectors. Applications include:

• Aerospace Industry
  Verifying connector durability against mechanical stresses that occur during installation, operation, and maintenance in aircraft and spacecraft systems.

• Connector Design and Development
  Engineers use the standard to validate and improve connector designs, ensuring accessory threads can withstand expected torque loads without failure.

• Maintenance and Safety Compliance
  Establishing acceptance criteria for used or repaired connectors in aerospace systems, ensuring continued operational safety and reliability.

• Supplier and Certification Audits
  Serving as a benchmark method for aerospace manufacturers and suppliers to demonstrate compliance with international aerospace standards.

Related Standards

• EN 2591-100: Aerospace series - Elements of electrical and optical connection - Test methods - Part 100: General
  Provides the foundational test methods and general requirements applicable alongside this standard.

• EN 2591-101: Aerospace series - Elements of electrical and optical connection - Test methods - Part 101: Visual examination
  Defines the visual inspection procedures for detecting physical damage or deformation post-testing.

• Additional parts of EN 2591 series cover various other connector tests and properties relevant to aerospace electrical and optical connectivity, facilitating comprehensive assessment protocols.

Keywords: EN 2591-423, aerospace connector testing, thread strength test, electrical connector standards, optical connection elements, torque testing aerospace connectors, connector accessory thread durability, aerospace electrical connection quality assurance