How it works
These are the parts of a railroad car, freight first. The boxcar is drawn whole. Then the two things every car has are enlarged: the coupler at each end and the truck under each end.
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Four drawings
View 1 is a classic boxcar from the side: body, sliding side door, the running board on the roof, ladder, grab irons, sill step, and the hand brake wheel on its shaft. View 2 enlarges the coupler end, with the center sill cut away to show the draft gear. View 3 is one truck. View 4 is the end of a passenger car, from the side and end-on.
What carries the load
Of all the parts of a rail car, the center sill is the backbone: pulling and pushing pass along it from coupler to coupler. The body rests on the bolster of each truck, the bolster rests on springs, and the side frames carry that weight out to the axles and wheels.
- A truck swivels under the car body on a center pin, which lets a long car go round a curve.
- A running board is a walkway for trainmen along the roof.
Questions and answers
What are the parts of a train carriage called?
On a passenger car, or carriage: the vestibule at each end, where passengers get on; the end door; the diaphragm, a flexible passage to the next car; and the windows. Underneath are couplers and trucks like a freight car's.
What is the part that connects train cars called?
The coupler. In North America it is a knuckle coupler: the hooked knuckle of one car locks into the knuckle of the next. A worker pulls the uncoupling lever from the side to part them, without stepping between the cars.
What are the wheels under a train car called?
A truck, or a bogie outside North America: a small frame with two axles and four wheels. One sits under each end of the car and carries half its weight.
What is a journal box?
A metal box over the end of an axle. It holds the bearing the axle turns in and the oil that keeps it running. In Britain it is called an axle box.