Bogie

A bogie (/ˈboʊɡi/ BOH-ghee) (or truck in North American English) comprises two or more wheelsets (two wheels on an axle), in a frame, attached under a vehicle by a pivot.

It may be mounted on a swivel, as traditionally on a railway carriage or locomotive, additionally jointed and sprung (as in the landing gear of an airliner), or held in place by other means (centreless bogies).

The concept took decades before it was widely accepted but eventually became a component of the vast majority of mainline locomotive designs.

The retractable stadium roof on Toronto's Rogers Centre used modified off-the-shelf train bogies on a circular rail.

The unusually large flanges on the steel wheels guide the bogie through standard railroad switches, and in addition keep the train from derailing in case the tires deflate.

For non-radial bogies, the more axles in the assembly, the more difficulty it has negotiating curves, due to wheel flange to rail friction.

EMD subsequently introduced the HTSC truck, essentially the HTCR stripped of radial components.

However, it also met with limited acceptance because of its relatively high purchase and maintenance costs, and customers have generally chosen GE Hi-Ad standard trucks for newer and rebuilt locomotives.

[14] The configuration, invented by British engineer John James Davidge Cleminson, was first granted a patent in the UK in 1883.

[15] The system was widely used on British narrow-gauge rolling stock, such as on the Isle of Man and Manx Northern Railways.

An articulated bogie (aka Jakob-type) is any one of a number of bogie designs that reduce weight, increase passenger comfort, and allow railway equipment to safely turn sharp corners, while reducing or eliminating the "screeching" normally associated with metal wheels rounding a bend in the rails.

There are a number of such designs, and the term is also applied to train sets that incorporate articulation in the vehicle, as opposed to the bogies themselves.

Articulated bogies add a second pivot point between the two axles (wheelsets) to allow them to rotate to the correct angle even in these cases.

Bogie on a Czech Railways side-tipper car
Experiment , the first successful American locomotive with a bogie, built in 1831 to a design by civil engineer John B. Jervis
Bogies allow the wheelsets to more closely follow the direction of the rails when travelling around a curve in the railroad.
Displacements of a bogie
A diagram of an American-style truck showing the names of its parts and showing the journal boxes to be integral parts of the side frame . [ 7 ] [ 8 ] [ 9 ] The journal boxes house plain bearings .
Side view of a SEPTA K-Car bogie
Mockup of the pneumatic bogie system of an MP 89 carriage used on the Meteor metro , showing the two special wheelsets [ 12 ]
An American-built broad-gauge passenger car in South Australia , one of six fitted with Cleminson self-steering axles; pictured in 1890, ten years after their purchase
Articulated bogie on an NCTD Sprinter Siemens Desiro VT642