changes in the reception hole of the pin coupling relations of a long iron

摘要

An improved pinhole for a standard A.A.R. (Association of American Railroads) type "F" coupler having a top and bottom strap formed in a compound curve generated by multiradii. The straps formed thusly provide reduced stress levels in tension and compression through the coupler centerline as well as through the rear corner radii at the pinhole thereby minimizing coupler failures at these points.