Diesel Locomotive

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diesel locomotive

[′dē·zəl ‚lō·kə′mōd·iv]
(mechanical engineering)

Diesel Locomotive


a locomotive in which the primary power plant is a diesel-type internal-combustion engine. The major components of a diesel locomotive are a diesel engine, power transmission, crew compartment, and auxiliary equipment. The diesel engine, located in the engine compartment, transforms the thermal energy of a combustible fuel into mechanical or electrical energy, which by means of a mechanical, hydraulic, or electric power transmission is realized as motion of the wheel pairs.

The idea of using a heat engine in a locomotive arose at the end of the 19th century. The precursors of diesel locomotives were railcars and motor trolleys, which were produced mainly for in-traplant transport. In the period 1908–12, the Russian engineer V. I. Grinevetskii produced an experimental internal-combustion engine suitable for operation under the variable loads arising from use in a locomotive; a diesel locomotive was designed with such an engine but was not constructed. In 1922 the Soviet engineer A. N. Shelest proposed an original design for a diesel engine with a mechanical gas generator; his idea was realized only in the 1950’s in Sweden. The first main-line diesel locomotive was produced in the USSR according to a design by Ia. M. Gakkel’. The majority of diesel locomotives are equipped with electric power transmissions. In such installations the crankshaft of the primary power plant turns the armature of the primary electric generator, which produces electric current for electric traction motors. The rotational motion of the armatures of the traction motors is transmitted to the wheel pairs through a gear drive.

The crew compartment includes the main frame, two-, three-, or four-axle trucks with wheel pairs, axle boxes, and a spring suspension. The car body is mounted on the main frame. Diesel locomotives are designed with one-, two, and three-section car bodies. The engineer’s cab, from which the locomotive is operated, is located inside the car body. The engineer uses a controller to set a given crankshaft rotation speed for the diesel engine. Changes in the operating regimes of the electric generator and electric traction motors are accomplished automatically according to track conditions. The cab is usually separated from the engine compartment by an equipment compartment that houses instruments and devices for switching in the power transmission. In addition to the engine, the engine compartment also contains the main generator, air compressor, storage battery, filters, and other equipment.

The diesel locomotive is an economical locomotive: energy is used with approximately six times higher efficiency than in a steam locomotive. Current diesel locomotives have a nominal efficiency between 28 and 32 percent and are capable of speeds of 120–160 km/hr and higher.


Iakobson, P. V. Istoriia teplovoza v SSSR. Moscow, 1960.
Teplovoz TE3, 5th ed. Moscow, 1973.
Teplovozy SSSR: Katalog-spravochnik. Moscow, 1974.