Bogie exchange
Bogie exchange is a system for operating railway wagons on two or more gauges to overcome difference in the track gauge. To perform a bogie exchange, a car is converted from one gauge to another by removing the bogies or trucks (the chassis containing the wheels and axles of the car), and installing a new bogie with differently spaced wheels. It is generally limited to wagons and carriages, though diesel locomotives can be exchanged if enough time is available.
Bogie wagons can have their gauge changed by lifting them off one set of bogies and putting them back down again on another set of bogies. The pin that centres the bogies and the hoses and fittings for the brakes must be compatible. A generous supply of bogies of each gauge is needed to accommodate the ebb and flow of traffic. The bogies and wagons also need to have standardized hooks, etc., where they may be efficiently lifted. The two wheel sets on four-wheel wagons can be changed as well if the wagon has been designed accordingly.
Steam engines can be designed for more than one gauge, by having, for example, reversible wheel hubs that suit two alternative gauges. This was done in the 1930s and beyond in Victoria for possible gauge conversion, though no engines were ever converted in this manner other than one heritage engine (R766). Some 1,000 mm (3 ft 3 3⁄8 in) metre gauge Garratt locomotives of East Africa were designed for easy conversion to 3 ft 6 in (1,067 mm) gauge, though again none ever was.
In 1944, the LMS re-gauged a pair of "Jinty" 0-6-0 tank locomotives - originally built to UK 4 ft 8 1⁄2 in (1,435 mm) standard gauge - for use on its 5 ft 3 in (1,600 mm) gauge Northern Counties Committee (NCC) lines in Northern Ireland; re-designated as Class Y, they largely undertook shunting work on dockyard lines in Belfast. The re-gauging was performed by simply reversing the wheel centres so that the spokes dished outwards.
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