SIST EN 2645:2006

Overview

SIST EN 2645:2006 is a European standard developed by CEN and the European Association of Aerospace Manufacturers (AECMA-STAN) that specifies the dimensional characteristics of lockrings for threaded adaptors used in aerospace applications. The standard governs the precise measurements and configurations of lockrings designed to secure threaded adaptors, ensuring reliable and consistent performance in the aerospace industry. Approved in 2005, this standard is mandatory for member countries of CEN and underpins key aerospace manufacturing and maintenance practices across Europe.

Key Topics

• Scope and Purpose: SIST EN 2645:2006 focuses on the dimensional specifications for lockrings used with threaded adaptors in aerospace settings. This ensures proper fit, security, and functionality of locking mechanisms critical in aerospace fuel, hydraulic, and pneumatic systems.

• Dimensional Requirements: The standard details exact dimensions for lockrings including sizes for teeth, diameters (d1 to d7), lengths (l1 to l3), and angles (α1, α2). These dimensions are expressed in millimeters with strict tolerances to guarantee interchangeability and safety.

• Configuration Details: Includes specifications on the number of teeth (n1, n2), identification markings such as the removal of one tooth for metric items, and surface roughness criteria to meet aerospace performance standards.

• Designation System: A clear coding method is provided for identifying lockrings according to the dimensional characteristics outlined in the standard. For example, a lockring designated "LOCKRING EN 2645 - 10" indicates compliance and size per the specification table.

• Compliance and Standardization: The document outlines that the standard must be adopted as a national standard by CEN member countries, replacing conflicting national standards by mid-2006.

Applications

• Aerospace Manufacturing: SIST EN 2645:2006 standardizes components in the production of aerospace threaded adaptors, ensuring that lockrings provide secure connections critical to aircraft safety and integrity.

• Maintenance and Repair: Maintenance engineers and technicians rely on the dimensional criteria in EN 2645 for component replacement, ensuring that aftermarket or replacement lockrings precisely match original specifications.

• Quality Assurance: Aerospace quality control utilizes this standard to verify that manufactured lockrings conform to dimensional tolerances and design rules, helping prevent failures due to improper locking components.

• Supply Chain Consistency: By adhering to EN 2645, suppliers across Europe provide uniform lockrings, facilitating streamlined inventory management and interchangeability across aerospace programs.

Related Standards

• AECMA and Aerospace Component Standards: EN 2645 integrates within the broader framework of aerospace component standards established by AECMA, supporting harmonized designs for fittings, adaptors, and connectors.

• Threaded Connector Standards: Complements other EN and ISO standards covering threaded connectors used in aerospace fluid and gas systems.

• Surface Finish and Material Standards: While EN 2645 specifies dimensional and roughness characteristics, related standards govern material properties and coatings essential for aerospace durability.

Keywords: SIST EN 2645:2006, aerospace lockrings, threaded adaptors, lockring dimensions, aerospace standards, CEN aerospace standard, aerospace component specification, lockring for aerospace adaptors, aerospace manufacturing standards, aerospace maintenance standards