Projects

Freight Car Coupler AAR Qualification Testing

Description

CTLGroup was contracted to conduct qualification tests on coupler body castings for freight car applications in the North American market.  Couplers were tested in accordance to the Association of American Railroads specifications (AAR) Manual of Standard and Recommended Standards (MSRP) M-211 “Foundry and Product Approval Requirements for the Manufacture of Couplers, Coupler Yokes, Knuckles, Follower Blocks, and Coupler Parts”.

The objectives of the tests were to evaluate the performance characteristics and structural strength of coupler bodies validating manufacturing quality and design.  Castings were subjected to static loads and ultimate load conditions in accordance to the AAR standards.

Static tests were performed by reacting one coupler to a high strength dummy knuckle.  A static tension load of 700,000 lbs was applied to the coupler assembly.  Reference measurements were performed pre- and post- static tension tests to determine the permanent set in the coupler bodies and its conformance to the AAR requirements.

Individual coupler bodies were tested to ultimate strength, as defined by the AAR, of 900,000 lbs.  These tests were performed using a high-strength knuckle in lieu of a standard knuckle to assess the performance of the coupler body under overload conditions.