The primary purposes of a railway joint, comprising two joint bars or commonly known as angle bars, are to secure the two ends of the steel rail in place and serve as a bridge or girder between these rail ends. Railway joint bars play a critical role in preventing lateral and vertical movement of the rail ends while allowing longitudinal movement for the steel rails to expand or contract. It's important to note that the AREMA railway joint is often considered the weakest part of the track structure and should be minimized whenever feasible.
Railway joint bars are specifically matched to the corresponding rail section. Each rail section has a designated drilling pattern, which includes the spacing of holes from the end of the rail and the dimension above the base. It is crucial to use joint bars that match this drilling pattern to ensure proper fishing angles and radii. Failure to do so can result in an inadequately supported railway joint, promoting rail defects such as head and web separations, as well as bolt hole breaks. Matching the right joint bars to the rail sections is essential for maintaining the structural integrity and safety of the railway track.
