WHEELSET
Wheelset
A wheelset is the wheel-axle assembly of a railroad car. The frame assembly beneath each end of a car, railcar or locomotive that holds the wheelsets is called the bogie . Most North American freight cars have two bogies with two or three wheelsets, depending on the type of car; short freight cars generally have no bogies but instead have two wheelsets.The above text is a snippet from Wikipedia: Wheelset (rail transport)
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