|
|
|
|
Switcher
|
| |
|
| |
A switcher or shunter (Great Britain: shunter; Australia: shunter or yard pilot; USA: switcher (or switch engine), except Pennsylvania Railroad: shifter) is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been brought in, and generally moving railroad cars around - a process usually known as switching (UK: shunting).
Discussion
Ask a question about 'Switcher' Start a new discussion about 'Switcher' Answer questions from other users |
Encyclopedia
A switcher or shunter (Great Britain: shunter; Australia: shunter or yard pilot; USA: switcher (or switch engine), except Pennsylvania Railroad: shifter) is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been brought in, and generally moving railroad cars around - a process usually known as switching (UK: shunting). They do this in classification yards. Switchers may also make short transfer runs and even be the only motive power on branch lines and switching and terminal railroads.
The typical switcher is optimised for its job, being relatively low-powered but with a high starting tractive effort for getting heavy cars rolling quickly. Switchers are geared to produce high torque but are restricted to low top speeds and have small diameter driving wheels .
Switching is hard work, and heavily used switch engines wear out quickly from the abuse of constant hard contacts with cars and frequent starting and stopping.
Power types
Diesel
Diesel switchers tend to have a high cab and often lower and/or narrower hoods (bonnets) containing the diesel engines, for all round visibility. Slugs are often used because they allow even greater tractive effort to be applied. Nearly all slugs used for switching are of the low hood, cabless variety. Good visibility in both directions is critical, because a switcher may be running in either direction; turning the locomotive is time-consuming. Some earlier diesel switchers used cow-calf configurations of two powered units in order to provide greater power.
Electric
Now, the vast majority of switchers are diesels, but countries with near-total electrification, like Switzerland, use electric switchers. Small industrial shunters are sometimes of the battery-electric type. An early battery-electric shunting locomotive is shown here . Flywheel energy storage was also used experimentally by Sentinel.
Three power
The "three power locomotive" was a type of switcher developed in the USA in the 1920s. It was a diesel-electric locomotive which could alternatively run on batteries (for use inside warehouses) or from a third rail or overhead supply . It was a type of electro-diesel locomotive.
Steam
Steam shunter/switchers are now mainly of historical interest. Steam switchers were either tank locomotives or had special (smaller) tenders, with narrow coal bunkers and/or sloped tender decks to increase rearward visibility. Headlights, where carried, were mounted on both ends.
Small industrial shunters have sometimes been fireless locomotives and a few of these are still at work in Germany.
Non-US shunters
British and European locomotives of this type tend to be much smaller than the common size in the United States. Current British shunters are 0-6-0 diesel-electrics, Class 08 and Class 09, of 350-400 horsepower. These were developed from similar locomotives supplied by the English Electric Company to the Big Four British railway companies in the 1930s and 1940s, e.g. the LNER Class J45/DES1 . Similar locomotives were exported to the Netherlands (e.g. NS Class 600) and Australia (e.g. Victorian Railways F class (diesel)).
In continental Europe 0-6-0 diesel-hydraulics, similar to the short-lived British Rail Class 14, are widely used. Two examples on the Turkish State Railways are TCDD DH33100 and TCDD DH7000.
Station pilot
A station pilot is a shunting engine based at a major passenger station, used for moving trains or carriages between platforms, assembling trains, and other passenger train shunting tasks. It is a predominantly British term.
Station pilots are no longer used in the UK as the majority of passenger trains are formed with multiple units; the few locomotive-hauled passenger trains are shunted by the train engine rather than a dedicated station pilot.
See also
|
| |
|
|
