Locomotives of India

Indian Railways operates India's railway system and comes under the purview of the Ministry of Railways of Government of India. As of 2023, it maintains over 108,706 km (67,547 mi) of tracks and operates over 13,000 trains daily with a fleet of 14,800 locomotives. The railways primarily operates a fleet of electric and diesel locomotives along with a few compressed natural gas (CNG) locomotives. Steam locomotives are operated on mountain railways and on heritage trains.
The history of the Indian Railway began in 1832 with the proposal to construct the first railway line in India at Madras. In 1837, the first train ran on Red Hill railway line between Red Hills and Chintadripet in Madras and was hauled by a rotary steam engine imported from England. In 1852, a steam locomotive imported from England was tried at Byculla. In 1853, the first passenger train ran between Bombay and Thane which had 14-carriages hauled by three steam locomotives: the Sahib, Sindh and Sultan. In 1877, an Ajmer built F-1/734 Steam Locomotive became the first indigenously built locomotive in India. In 1925, the first electric train ran between Bombay and Kurla, hauled by a Swiss Locomotive and Machine Works (SLM) 2,400 hp (1,800 kW) electric locomotive on 1500 V DC traction. The first diesel locomotive used in India was fabricated by North British Locomotive Company in 1954.
Chittaranjan Locomotive Works, commissioned in 1950, was the first locomotive manufacturing unit in India. Banaras Locomotive Works, commissioned in 1961, is the second locomotive manufacturing unit operated by Indian Railways. In the 1960s, Integral Coach Factory-Chennai (ICF) started developing self-propelled Electric multiple units for short-haul and local routes. BHEL and Patiala Locomotive Works, established in 1981, also manufacture locomotives in India. In 2015, the first compressed natural gas (CNG) powered trains were rolled out by ICF. In 2018, a semi-high speed self-propelled train-set capable of reaching speeds of over 160 km/h (99 mph) was rolled out from ICF. As of 2023, Indian Railways maintains over 108,706 km (67,547 mi) of tracks and operates over 13,000 trains daily with a fleet of over 14,800 locomotives. 37% of the trains are operated by diesel locomotives and rest mostly by electric locomotives. As of December 2023, Indian Railways had 10,238 electric and 4,543 diesel locomotives amongst others.
Locomotives are classified by track gauge, motive power, function, power rating and model in a four- or five-letter code. The locomotives may be Longer Hood Front (LHF), where the driver cabin is behind the hood of the engine or Short Hood Front (SHF), where the cabin is located towards the front.
In 1925, the first electric train ran between Bombay and Kurla, hauled by a imported SLM locomotive on a DC traction. In 1927, the first electric locomotive hauled passenger train was pulled by an imported WCP-1. In 1957, Indian Railways adopted 25 kV 50 Hz AC traction with the first runs beginning in December 1959 with the WAM-1 locomotives.
In 1925, the Electric Multiple Units (EMU) introduced in Bombay were 1.5KV DC units imported were from Cammell Laird and Uerdingenwagonfabrik. In the 1960s, EMUs were developed by Integral Coach Factory (ICF) in Chennai. Indian Railways uses multiple DC units in operation in several suburban sections which are classified from WCU-1 through WCU-15. BHEL developed AC-DC dual use EMUs which can run on 25kV AC and 1.5kV DC traction lines. In the late 1990s, MEMUs were developed which ran on 25KV AC power. AC Electric multiple units are designated WAU-1 to WAU-4. In 2019, ICF rolled out three-phase AC units to replace conventional DC units.
In 1954, the first diesel locomotive was used in India, which was manufactured by North British Locomotive Company. In 1958, WDM-1, the first locomotive used for mainline traffic was imported from ALCO. In 1964, the first broad-gauge WDM-2 diesel locomotive was rolled out by Banaras Locomotive Works.
In 2009, a YDM-4 locomotive was converted to a broad gauge shunter by Golden Rock Railway Workshop, codenamed WCDS-6, with C for "Converted" and delivered to RITES.
In 1958, the Commonwealth Engineering of Australia supplied an unknown number of 400 hp (300 kW), 83-seat broad-gauge diesel-mechanical railcars to Indian Railways, classified as WRD-1. Powered by a pair of 200 hp Leyland engines, it had an axle arrangement of 1A-1A1, and a top speed of 110 km/h (68 mph).
In 1993-94, diesel multiple units (DMU) were introduced into service. Depending on their transmission system, they are classified as DEMU (diesel-electric transmission) or DHMU (diesel-hydraulic transmission). With increase in electrifiction, DEMUS have been replaced by MEMUs in stages.
In the 19th century, the railway companies ordered custom-built steam locomotives, usually from British manufacturers. With non-standardized and multiple designs, manufacturing cost was high and production was slow. During the 1890s, Indian railway companies imported locomotives from Germany and the United States when British manufacturers were suffering from work outages. List of locomotives used below:
In the early 1900s, the British Engineering Standards Committee (later the British Engineering Standards Association) began designing a series of locomotives for use by Indian railways. The first two designs emerged in 1903: a 4-4-0 passenger and 0-6-0 goods. They were revised in 1905 and 1906 with additional heavier, more-powerful locomotives:
These advisory BESA designs were customized by the railway companies, which used different classification systems; only the state-operated railways used the class designations SP, SG, PT, HP, AP, HG and HT. When superheating was accepted, superheated versions were classified SPS, SGS and so on (if built with superheaters) and SPC, SGC and so on (if converted from saturated to superheated).
After World War I, larger and more-powerful locomotives were designed by British consulting engineers for the Indian government. They began to operate from 1927:
During World War II, large numbers of 2-8-2 locomotives were acquired from the United States and Canada and classified AWD and CWD. The Baldwin Locomotive Works adapted the USATC S160 Class locomotive design for India, and it became class AWC. Sixty broad-gauge locomotives were built in 1944 as part of an order of 180 S160 engines. In addition to modified frame spreaders, axles, cylinders, and cab, the Indian locomotives had a turbo generator and electric lighting (not included in the standard European design). Many parts (including boilers) were identical to those in standard-gauge locomotives.
Although new classes were designed shortly before the war, many did not enter service until the post-war period. The new classes were indicated by the change of broad-gauge prefix from X to W, and plans were implemented to begin manufacturing locomotives in India. The new classes were:
All broad-gauge steam locomotives in India have been withdrawn from normal service, with only occasional steam specials continuing to operate.
In 2015, the first compressed natural gas (CNG) powered Multiple unites were rolled out by ICF. In 2020, Southern Railway zone introduced the first battery/AC dual shunter termed as WAG5HA with "H" for hybrid.