A device placed beween the top of the rail and the rail vehicle wheel to prevent vehicle movement when brakes are not applied or are defective.
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WHEEL FLANGE
In rail systems, a projecting edge or rim on the circumference of a steel wheel that is designed to keep the wheel on a rail. (TRB)
WHEEL TREAD
In rail systems, the exterior cylindrical or conical surface of a steel wheel that comes in contact with the rail. (TRB)
WHEELCHAIR LIFT
A device used to raise and lower a platform in a transit vehicle for accessibility by people with disabilities.