Locomotives for Leasing and Sale at HEROS
Locomotives were one of the key inventions in the history of rail transport. By concentrating the power in a locomotive and being able to pull several relatively simple unpowered carriages, they achieved greater efficiency than, for example, road vehicles in terms of manpower and maintenance requirements. Locomotives are a subset of traction units. The most traditional solution is to divide the train into a locomotive, which is solely responsible for the drive, and a train of carriages, which carries and encloses the passengers or goods. The most important advantages of this solution are the flexibility of train formation (e.g. possibility of using different train lengths) and the independence between the locomotive and the carriage or train of carriages for maintenance and other tasks.
Over the course of history, many different types of locomotives have been developed. They can be grouped, for example, according to the primary energy source, such as steam, diesel or electrical energy (energy obtained from the overhead wire), or, less commonly, batteries or gas, used to power the locomotive. Terms such as steam locomotive, internal combustion locomotive, diesel locomotive, electric locomotive, battery locomotive or electro-diesel (dual-mode) locomotive are used for them.
In diesel locomotives, a distinction is also made between the different ways in which power is transmitted from the diesel engine to the wheelset. People in the industry talk, for example, about diesel-hydraulic or diesel-electric locomotives. The diesel-hydraulic main line locomotives are mostly equipped with hydrodynamic transmissions, while construction vehicles are often manufactured with hydrostatic transmissions. Sometimes the number of independent engine-and-power-transmission units also yields the name. For example, the term ‘multiple-engine locomotive’ is used when several diesel engines drive their own generators, all of which feed into a common drive system, and ‘genset locomotive’ is used when a diesel engine with its own generator is available for each wheelset.
Locomotives are also referred to differently according to their purposes. Examples are main line locomotives, freight locomotives, passenger locomotives, universal locomotives, shunting locomotives, shifting/switching locomotives, construction locomotives and factory locomotives.
Locomotives for passenger transport must have the additional equipment required for the respective carriage types to pull passenger trains and to supply them with the respective drive energy and the deployment-specific control or communication (e.g. through public address systems). This often includes head-end power, facilities for communication with a train conductor or passengers and door release, door closing and door locking, or possibly devices for specific pre-departure procedures. There are also different processes for side-selective door release. Custom solutions have been developed independently of one another in different countries. Each solution is only functional if the locomotive and the carriages can work according to the same system. For cross-border transport, train protection systems are particularly important for the respective countries of deployment. A higher maximum speed is often desired for passenger trains, but the trains are relatively light. Locomotives that provide both the high tractive forces for freight trains and the higher speeds for passenger trains and are also equipped with the appropriate facilities for passenger transport are often referred to as universal locomotives or general-purpose locomotives.
For goods transport, maximum operating speeds of only 100 km/h, amongst other things, are required. A higher tractive force is usually required to move heavier trains. This can lead to special requirements for the traction system, bogies or wheelsets.
Depending on the intended use, the arrangement of the driver’s cabs also varies. For example, we speak of ‘centre-cab locomotives’ or ‘mid-cab locomotives’ if there is a room for the locomotive driver approximately in the middle of the locomotive for both directions of travel together. In contrast, a bidirectional locomotive has two driver’s cabs, one at each end of the locomotive. As a special form, unidirectional locomotives or distributed power units are operated in pairs as a ‘double locomotive’ or distributed power unit train or are used in combination with a driving trailer in push–pull operation or as a reversing train and are remotely controlled in one direction from the driving trailer.
