Brake van

Brake van and guard's van are terms used mainly in the UK, Australia and India for a equipped with a hand brake which can be applied by the guard. The equivalent North American term is caboose, but a British brake van and a caboose are very different in appearance, because the former usually has only four wheels, while the latter usually has bogies.

Many British freight trains formerly had no continuous brake so the only available brakes were those on the locomotive and the brake van. Because of this shortage of brake power, the speed was restricted to 25 mph (40 km/h). The brake van was marshalled at the rear of the train so both portions of the train could be brought to a stand in the event of a coupling breaking.

When freight trains were fitted with continuous braking, brake vans lost their importance, and were discontinued by many railways. However, they still continue on some important railways, such as the Indian Railways, besides the heritage railways.

Railways were a formalised development of industrial tramways, which had found need on occasions to add additional braking capacity by adding an empty truck to the rear of a group of tramcars. This allowed the "locomotive" — often a cableway powered by a steam engine at the surface — to operate both safely and, more importantly, at higher speed.

The first railways, such as the pioneering Liverpool and Manchester Railway of 1830, used a version of the tramways buffer and chain coupling, termed a screw-coupling. Vehicles are coupled by hand using a hook and links with a turnbuckle-like device that draws the vehicles together. Vehicles have buffers, one at each corner on the ends, which are pulled together and compressed by the coupling device. With no continuous brake across the entire train, the whole train was reliant on the braking capacity of the locomotive, and train lengths were restricted.

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