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78-451: The Indian locomotive class WDM-4 is a class of diesel–electric locomotive that was developed in 1962 by Electro-Motive Diesel for Indian Railways . The model name stands for broad gauge (W) , Diesel (D), Mixed traffic (M) engine, 4th generation (4). They entered service in 1962. A total of 72 WDM-4 locomotives were built between 1961 and 1962. Despite the introduction of more modern types of locomotives like WAP-1 and electrification,

156-471: A consist respond in the same way to throttle position. Binary encoding also helps to minimize the number of trainlines (electrical connections) that are required to pass signals from unit to unit. For example, only four trainlines are required to encode all possible throttle positions if there are up to 14 stages of throttling. North American locomotives, such as those built by EMD or General Electric , have eight throttle positions or "notches" as well as

234-429: A "reverser" to allow them to operate bi-directionally. Many UK-built locomotives have a ten-position throttle. The power positions are often referred to by locomotive crews depending upon the throttle setting, such as "run 3" or "notch 3". In older locomotives, the throttle mechanism was ratcheted so that it was not possible to advance more than one power position at a time. The engine driver could not, for example, pull

312-609: A Rational Heat Motor ). However, the large size and poor power-to-weight ratio of early diesel engines made them unsuitable for propelling land-based vehicles. Therefore, the engine's potential as a railroad prime mover was not initially recognized. This changed as research and development reduced the size and weight of the engine. In 1906, Rudolf Diesel, Adolf Klose and the steam and diesel engine manufacturer Gebrüder Sulzer founded Diesel-Sulzer-Klose GmbH to manufacture diesel-powered locomotives. Sulzer had been manufacturing diesel engines since 1898. The Prussian State Railways ordered

390-592: A diesel locomotive from the company in 1909, and after test runs between Winterthur and Romanshorn , Switzerland, the diesel–mechanical locomotive was delivered in Berlin in September 1912. The world's first diesel-powered locomotive was operated in the summer of 1912 on the same line from Winterthur but was not a commercial success. During test runs in 1913 several problems were found. The outbreak of World War I in 1914 prevented all further trials. The locomotive weight

468-504: A diesel-driven charging circuit. ALCO acquired the McIntosh & Seymour Engine Company in 1929 and entered series production of 300 hp (220 kW) and 600 hp (450 kW) single-cab switcher units in 1931. ALCO would be the pre-eminent builder of switch engines through the mid-1930s and would adapt the basic switcher design to produce versatile and highly successful, albeit relatively low powered, road locomotives. GM, seeing

546-465: A flashover (also known as an arc fault ), which could result in immediate generator failure and, in some cases, start an engine room fire. Current North American practice is for four axles for high-speed passenger or "time" freight, or for six axles for lower-speed or "manifest" freight. The most modern units on "time" freight service tend to have six axles underneath the frame. Unlike those in "manifest" service, "time" freight units will have only four of

624-494: A large number of Co-Co diesel locomotives producing at least 2,600 hp (1,900 kW) with road switcher cabs to achieve this aim. Thus Indian Railways began looking at various diesel-electric designs. Initially, the Indian railways invited tenders to build locomotives to the new specification. The following responses were received: Each company submitted their prototypes and Indian Railways designated these prototypes as

702-577: A major manufacturer of diesel engines for marine and stationary applications, in 1930. Supported by the General Motors Research Division, GM's Winton Engine Corporation sought to develop diesel engines suitable for high-speed mobile use. The first milestone in that effort was delivery in early 1934 of the Winton 201A, a two-stroke , mechanically aspirated , uniflow-scavenged , unit-injected diesel engine that could deliver

780-510: A modern, well designed and engineered fuel-injected , computer-controlled , multi-valve and optionally variable-valve timing -equipped gasoline engine using good fuel can achieve remarkable flexibility in automobile applications, with sufficient torque even at low engine speeds and a relatively flat power output from 1,500 to 6,500 RPM, allowing easy cruising and forgiving low-speed behaviour. However, achieving maximum power for strong acceleration or high road speed still requires high RPM. Though

858-410: A nearly imperceptible start. The positioning of the reverser and movement of the throttle together is conceptually like shifting an automobile's automatic transmission into gear while the engine is idling. Power band The power band of an internal combustion engine or electric motor is the range of operating speeds under which the engine or motor is able to output the most power , that is,

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936-421: A prototype diesel–electric locomotive for "special uses" (such as for runs where water for steam locomotives was scarce) using electrical equipment from Westinghouse Electric Company . Its twin-engine design was not successful, and the unit was scrapped after a short testing and demonstration period. Industry sources were beginning to suggest "the outstanding advantages of this new form of motive power". In 1929,

1014-486: A real prospect with existing diesel technology. Before diesel power could make inroads into mainline service, the limitations of diesel engines circa 1930 – low power-to-weight ratios and narrow output range – had to be overcome. A major effort to overcome those limitations was launched by General Motors after they moved into the diesel field with their acquisition of the Winton Engine Company ,

1092-484: Is because clutches would need to be very large at these power levels and would not fit in a standard 2.5 m (8 ft 2 in)-wide locomotive frame, or would wear too quickly to be useful. The first successful diesel engines used diesel–electric transmissions , and by 1925 a small number of diesel locomotives of 600 hp (450 kW) were in service in the United States. In 1930, Armstrong Whitworth of

1170-533: Is better able to cope with overload conditions that often destroyed the older types of motors. A diesel–electric locomotive's power output is independent of road speed, as long as the unit's generator current and voltage limits are not exceeded. Therefore, the unit's ability to develop tractive effort (also referred to as drawbar pull or tractive force , which is what actually propels the train) will tend to inversely vary with speed within these limits. (See power curve below). Maintaining acceptable operating parameters

1248-502: Is generally limited to low-powered, low-speed shunting (switching) locomotives, lightweight multiple units and self-propelled railcars . The mechanical transmissions used for railroad propulsion are generally more complex and much more robust than standard-road versions. There is usually a fluid coupling interposed between the engine and gearbox, and the gearbox is often of the epicyclic (planetary) type to permit shifting while under load. Various systems have been devised to minimise

1326-431: Is the product of torque multiplied by speed of rotation (analogous to force multiplied by speed in a linear system), so peak power is produced in the upper speed range where there's both high torque and high RPM. In turbocharged and supercharged engines with potential for abundant torque, an intake pressure regulation system often limits torque to a near-constant figure across the engine speed range to reduce stresses on

1404-405: Is the range of RPM around peak power output. The power band of an internal combustion gasoline automobile engine typically starts at midrange engine speeds (around 4,000 RPM) where maximum torque is produced, and ends below the redline after reaching maximum power (above 5,000 RPM but less than 7,000 RPM). Diesel engines in cars and small trucks may develop maximum torque below 2,000 RPM with

1482-414: Is the same as placing an automobile's transmission into neutral while the engine is running. To set the locomotive in motion, the reverser control handle is placed into the correct position (forward or reverse), the brake is released and the throttle is moved to the run 1 position (the first power notch). An experienced engine driver can accomplish these steps in a coordinated fashion that will result in

1560-656: The Burlington Route and Union Pacific used custom-built diesel " streamliners " to haul passengers, starting in late 1934. Burlington's Zephyr trainsets evolved from articulated three-car sets with 600 hp power cars in 1934 and early 1935, to the Denver Zephyr semi-articulated ten car trainsets pulled by cab-booster power sets introduced in late 1936. Union Pacific started diesel streamliner service between Chicago and Portland Oregon in June 1935, and in

1638-723: The Busch-Sulzer company in 1911. Only limited success was achieved in the early twentieth century with internal combustion engined railcars, due, in part, to difficulties with mechanical drive systems. General Electric (GE) entered the railcar market in the early twentieth century, as Thomas Edison possessed a patent on the electric locomotive, his design actually being a type of electrically propelled railcar. GE built its first electric locomotive prototype in 1895. However, high electrification costs caused GE to turn its attention to internal combustion power to provide electricity for electric railcars. Problems related to co-ordinating

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1716-611: The Canadian National Railways became the first North American railway to use diesels in mainline service with two units, 9000 and 9001, from Westinghouse. However, these early diesels proved expensive and unreliable, with their high cost of acquisition relative to steam unable to be realized in operating cost savings as they were frequently out of service. It would be another five years before diesel–electric propulsion would be successfully used in mainline service, and nearly ten years before fully replacing steam became

1794-494: The DFH1 , began in 1964 following the construction of a prototype in 1959. In Japan, starting in the 1920s, some petrol–electric railcars were produced. The first diesel–electric traction and the first air-streamed vehicles on Japanese rails were the two DMU3s of class Kiha 43000 (キハ43000系). Japan's first series of diesel locomotives was class DD50 (国鉄DD50形), twin locomotives, developed since 1950 and in service since 1953. In 1914,

1872-488: The Società per le Strade Ferrate del Mediterrano in southern Italy in 1926, following trials in 1924–25. The six-cylinder two-stroke motor produced 440 horsepower (330 kW) at 500   rpm, driving four DC motors, one for each axle. These 44 tonnes (43 long tons; 49 short tons) locomotives with 45 km/h (28 mph) top speed proved quite successful. In 1924, two diesel–electric locomotives were taken in service by

1950-1003: The Soviet railways , almost at the same time: In 1935, Krauss-Maffei , MAN and Voith built the first diesel–hydraulic locomotive, called V 140 , in Germany. Diesel–hydraulics became the mainstream in diesel locomotives in Germany since the German railways (DRG) were pleased with the performance of that engine. Serial production of diesel locomotives in Germany began after World War II. In many railway stations and industrial compounds, steam shunters had to be kept hot during many breaks between scattered short tasks. Therefore, diesel traction became economical for shunting before it became economical for hauling trains. The construction of diesel shunters began in 1920 in France, in 1925 in Denmark, in 1926 in

2028-406: The electrification of the line in 1944. Afterwards, the company kept them in service as boosters until 1965. Fiat claims to have built the first Italian diesel–electric locomotive in 1922, but little detail is available. Several Fiat- TIBB Bo'Bo' diesel–locomotives were built for service on the 950 mm ( 3 ft  1 + 3 ⁄ 8  in ) narrow gauge Ferrovie Calabro Lucane and

2106-432: The 1,500 kW (2,000 hp) British Rail 10100 locomotive), though only few have proven successful (such as the 1,342 kW (1,800 hp) DSB Class MF ). In a diesel–electric locomotive , the diesel engine drives either an electrical DC generator (generally, less than 3,000 hp (2,200 kW) net for traction), or an electrical AC alternator-rectifier (generally 3,000   hp net or more for traction),

2184-459: The 1960s, the DC generator was replaced by an alternator using a diode bridge to convert its output to DC. This advance greatly improved locomotive reliability and decreased generator maintenance costs by elimination of the commutator and brushes in the generator. Elimination of the brushes and commutator, in turn, eliminated the possibility of a particularly destructive type of event referred to as

2262-523: The 1990s, starting with the Electro-Motive SD70MAC in 1993 and followed by General Electric's AC4400CW in 1994 and AC6000CW in 1995. The Trans-Australian Railway built 1912 to 1917 by Commonwealth Railways (CR) passes through 2,000 km of waterless (or salt watered) desert terrain unsuitable for steam locomotives. The original engineer Henry Deane envisaged diesel operation to overcome such problems. Some have suggested that

2340-665: The 72 WDM-4 locomotives, only 2 are officially preserved. #18001, the first locomotive, is preserved at the National Rail Museum , while 18086 is plinthed at Lucknow Diesel Locomotive Shed. #18004, #18022, #18098 and #18107 were purchased by Ircon International and sent to Bangladesh for construction work, but were withdrawn due to age. Diesel%E2%80%93electric locomotive Early internal combustion locomotives and railcars used kerosene and gasoline as their fuel. Rudolf Diesel patented his first compression-ignition engine in 1898, and steady improvements to

2418-600: The CR worked with the South Australian Railways to trial diesel traction. However, the technology was not developed enough to be reliable. As in Europe, the usage of internal combustion engines advanced more readily in self-propelled railcars than in locomotives: A diesel–mechanical locomotive uses a mechanical transmission in a fashion similar to that employed in most road vehicles. This type of transmission

Indian locomotive class WDM-4 - Misplaced Pages Continue

2496-895: The Netherlands, and in 1927 in Germany. After a few years of testing, hundreds of units were produced within a decade. Diesel-powered or "oil-engined" railcars, generally diesel–mechanical, were developed by various European manufacturers in the 1930s, e.g. by William Beardmore and Company for the Canadian National Railways (the Beardmore Tornado engine was subsequently used in the R101 airship). Some of those series for regional traffic were begun with gasoline motors and then continued with diesel motors, such as Hungarian BC (The class code doesn't tell anything but "railmotor with 2nd and 3rd class seats".), 128 cars built 1926–1937, or German Wismar railbuses (57 cars 1932–1941). In France,

2574-566: The United Kingdom delivered two 1,200 hp (890 kW) locomotives using Sulzer -designed engines to Buenos Aires Great Southern Railway of Argentina. In 1933, diesel–electric technology developed by Maybach was used to propel the DRG Class SVT 877 , a high-speed intercity two-car set, and went into series production with other streamlined car sets in Germany starting in 1935. In the United States, diesel–electric propulsion

2652-596: The WDM-4 class and WDM-2 class respectively. It is not known as to why Indian Railways decided to classify it as WDM-4, as no WDM-3 class existed when they were ordered. Technologically the General Motors WDM-4 was superior to ALCO WDM-2, but Indian Railways required a transfer of technology agreement that would allow these locomotives to be indigenously manufactured in India. Since General Motors did not agree to

2730-571: The WDM-4 was one of the fastest locomotives of Indian Railways serving both passenger and freight trains for nearly 40 years. A few decommissioned WDM-4 units were exported to Bangladesh . As of January 2020, all 72 locomotives have been withdrawn form service with two preserved. The history of WDM-4 begins in the early 1960s with the stated aim of the Indian Railways to remove steam locomotives from Indian Rails after recommendation of Karnail Singh Fuel Committee. Therefore, required building

2808-499: The War Production Board put a halt to building new passenger equipment and gave naval uses priority for diesel engine production. During the petroleum crisis of 1942–43 , coal-fired steam had the advantage of not using fuel that was in critically short supply. EMD was later allowed to increase the production of its FT locomotives and ALCO-GE was allowed to produce a limited number of DL-109 road locomotives, but most in

2886-433: The axles connected to traction motors, with the other two as idler axles for weight distribution. In the late 1980s, the development of high-power variable-voltage/variable-frequency (VVVF) drives, or "traction inverters", allowed the use of polyphase AC traction motors, thereby also eliminating the motor commutator and brushes. The result is a more efficient and reliable drive that requires relatively little maintenance and

2964-722: The benefits of an electric locomotive without the railroad having to bear the sizeable expense of electrification. The unit successfully demonstrated, in switching and local freight and passenger service, on ten railroads and three industrial lines. Westinghouse Electric and Baldwin collaborated to build switching locomotives starting in 1929. However, the Great Depression curtailed demand for Westinghouse's electrical equipment, and they stopped building locomotives internally, opting to supply electrical parts instead. In June 1925, Baldwin Locomotive Works outshopped

3042-420: The break in transmission during gear changing, such as the S.S.S. (synchro-self-shifting) gearbox used by Hudswell Clarke . Diesel–mechanical propulsion is limited by the difficulty of building a reasonably sized transmission capable of coping with the power and torque required to move a heavy train. A number of attempts to use diesel–mechanical propulsion in high power applications have been made (for example,

3120-422: The design of diesel engines reduced their physical size and improved their power-to-weight ratios to a point where one could be mounted in a locomotive. Internal combustion engines only operate efficiently within a limited power band , and while low-power gasoline engines could be coupled to mechanical transmissions , the more powerful diesel engines required the development of new forms of transmission. This

3198-443: The engine governor and electrical or electronic components, including switchgear , rectifiers and other components, which control or modify the electrical supply to the traction motors. In the most elementary case, the generator may be directly connected to the motors with only very simple switchgear. Originally, the traction motors and generator were DC machines. Following the development of high-capacity silicon rectifiers in

Indian locomotive class WDM-4 - Misplaced Pages Continue

3276-527: The engine and provide consistent handling without decreasing peak power. Powerbands can surpass 14,000 RPM in motorcycles and some racing automobiles, such as Formula One cars . Such high speeds are reached by using lightweight pistons and connecting rods with short strokes to reduce inertia, and thus stresses on parts. Advances in valve technology similarly reduce valve float at such speeds. As an engine grows larger (its stroke in particular), its power band moves to lower speeds. In more common applications,

3354-419: The engine and traction motor with a single lever; subsequent improvements were also patented by Lemp. Lemp's design solved the problem of overloading and damaging the traction motors with excessive electrical power at low speeds, and was the prototype for all internal combustion–electric drive control systems. In 1917–1918, GE produced three experimental diesel–electric locomotives using Lemp's control design,

3432-423: The engine driver operates the controls. When the throttle is in the idle position, the prime mover receives minimal fuel, causing it to idle at low RPM. In addition, the traction motors are not connected to the main generator and the generator's field windings are not excited (energized) – the generator does not produce electricity without excitation. Therefore, the locomotive will be in "neutral". Conceptually, this

3510-436: The engine from labouring at low speeds, or exceeding recommended operating speeds. A narrow power band is often compensated for by a power-splitting device such as a clutch or torque converter to efficiently achieve a wide range of speeds. A continuously variable transmission can also avoid the issues of a narrow power band by keeping the engine running at an optimal speed. In typical combustion engines found in vehicles,

3588-456: The first diesel railcar was Renault VH , 115 units produced 1933/34. In Italy, after six Gasoline cars since 1931, Fiat and Breda built a lot of diesel railmotors, more than 110 from 1933 to 1938 and 390 from 1940 to 1953, Class 772 known as Littorina , and Class ALn 900. In the 1930s, streamlined highspeed diesel railcars were developed in several countries: In 1945, a batch of 30 Baldwin diesel–electric locomotives, Baldwin 0-6-6-0 1000 ,

3666-480: The first known to be built in the United States. Following this development, the 1923 Kaufman Act banned steam locomotives from New York City, because of severe pollution problems. The response to this law was to electrify high-traffic rail lines. However, electrification was uneconomical to apply to lower-traffic areas. The first regular use of diesel–electric locomotives was in switching (shunter) applications, which were more forgiving than mainline applications of

3744-569: The following year would add Los Angeles, CA , Oakland, CA , and Denver, CO to the destinations of diesel streamliners out of Chicago. The Burlington and Union Pacific streamliners were built by the Budd Company and the Pullman-Standard Company , respectively, using the new Winton engines and power train systems designed by GM's Electro-Motive Corporation . EMC's experimental 1800 hp B-B locomotives of 1935 demonstrated

3822-406: The freight market including their own F series locomotives. GE subsequently dissolved its partnership with ALCO and would emerge as EMD's main competitor in the early 1960s, eventually taking the top position in the locomotive market from EMD. Early diesel–electric locomotives in the United States used direct current (DC) traction motors but alternating current (AC) motors came into widespread use in

3900-570: The limitations of contemporary diesel technology and where the idling economy of diesel relative to steam would be most beneficial. GE entered a collaboration with the American Locomotive Company (ALCO) and Ingersoll-Rand (the "AGEIR" consortium) in 1924 to produce a prototype 300 hp (220 kW) "boxcab" locomotive delivered in July 1925. This locomotive demonstrated that the diesel–electric power unit could provide many of

3978-404: The literal power band covers most of the operating RPM range, particularly in first gear (as there is no lower gear to shift down to, and no "flat spot" in which the engine does not produce any power), the effective band changes in each gear, becoming the range limited at the upper end by either the limiter, or a point roughly located between peak power and the redline where power drops off, and at

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4056-431: The locomotive business were restricted to making switch engines and steam locomotives. In the early postwar era, EMD dominated the market for mainline locomotives with their E and F series locomotives. ALCO-GE in the late 1940s produced switchers and road-switchers that were successful in the short-haul market. However, EMD launched their GP series road-switcher locomotives in 1949, which displaced all other locomotives in

4134-487: The lower end the engine's idling speed. A typical road-going ("high-speed") diesel has a narrower band, generating peak torque at lower RPM (often 1,500–2,000 RPM) but also with a sharper fall-off below this, and reaching peak power around 3500-4500 RPM, again rapidly losing strength above this speed. Turbocharged diesel engines with turbo lag (narrowed, exaggerated power band intrinsic to most turbocharged engines) may display this characteristic even more markedly. Therefore,

4212-678: The manufacturer's (or purchaser's/modifier's) choice of gearing, and appropriate use of the available ratios, is even more crucial to make best use of the available power and avoid being "bogged down" in flat spots. Larger diesel engines in locomotives and some watercraft use diesel-electric drives. This eliminates the complexities of extremely low gearing, as described below. The largest ("low-speed") diesels—large generators on land and marine diesels at sea—may turn at only hundreds of RPM or even below, with idling speeds of 20-30 RPM. These engines are usually two-stroke diesel engines . Electric motors are unique in many ways, especially when it comes to

4290-439: The maximum energy per unit of time. This usually means that maximum acceleration can be achieved inside this band (often at the cost of lower efficiency). While engines and motors have a large range of operating speeds, the power band is usually a much smaller range of engine speed, only half or less of the total engine speed range (electric motors are an exception—see the section on electric motors below). Specifically, power band

4368-581: The mid-1950s. Generally, diesel traction in Italy was of less importance than in other countries, as it was amongst the most advanced countries in the electrification of the main lines and as Italian geography makes freight transport by sea cheaper than rail transportation even on many domestic connections. Adolphus Busch purchased the American manufacturing rights for the diesel engine in 1898 but never applied this new form of power to transportation. He founded

4446-546: The multiple-unit control systems used for the cab/booster sets and the twin-engine format used with the later Zephyr power units. Both of those features would be used in EMC's later production model locomotives. The lightweight diesel streamliners of the mid-1930s demonstrated the advantages of diesel for passenger service with breakthrough schedule times, but diesel locomotive power would not fully come of age until regular series production of mainline diesel locomotives commenced and it

4524-402: The output of which provides power to the traction motors that drive the locomotive. There is no mechanical connection between the diesel engine and the wheels. The important components of diesel–electric propulsion are the diesel engine (also known as the prime mover ), the main generator/alternator-rectifier, traction motors (usually with four or six axles), and a control system consisting of

4602-584: The performance and reliability of the new 567 model engine in passenger locomotives, EMC was eager to demonstrate diesel's viability in freight service. Following the successful 1939 tour of EMC's FT demonstrator freight locomotive set, the stage was set for dieselization of American railroads. In 1941, ALCO-GE introduced the RS-1 road-switcher that occupied its own market niche while EMD's F series locomotives were sought for mainline freight service. The US entry into World War II slowed conversion to diesel;

4680-510: The power band. The exact characteristics vary greatly with the type of electric motor. The maximum torque of a universal motor (vacuum cleaner, small machines, drills, starter motors) occurs at zero rotation rate (when stalled) and falls for higher RPM. For induction motors connected to a fixed frequency AC source (most common in large applications), the maximum torque is usually just below the synchronous RPM, sinks to zero for this RPM and becomes negative above it (induction generator); at low RPM

4758-480: The power peak below 5,000 RPM. A mechanical transmission with a selection of different gear ratios is designed to make satisfactory power available over the full range of vehicle speeds. The goal of the selection of gear ratios is to keep the engine operating in its power band. The narrower the band, the more gears are needed, closer together in ratio. By careful gear selection, an engine can be operated in its power band, throughout all vehicle speeds. Such use prevents

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4836-484: The prime mover and electric motor were immediately encountered, primarily due to limitations of the Ward Leonard current control system that had been chosen. GE Rail was formed in 1907 and 112 years later, in 2019, was purchased by and merged with Wabtec . A significant breakthrough occurred in 1914, when Hermann Lemp , a GE electrical engineer, developed and patented a reliable control system that controlled

4914-450: The required performance for a fast, lightweight passenger train. The second milestone, and the one that got American railroads moving towards diesel, was the 1938 delivery of GM's Model 567 engine that was designed specifically for locomotive use, bringing a fivefold increase in life of some mechanical parts and showing its potential for meeting the rigors of freight service. Diesel–electric railroad locomotion entered mainline service when

4992-405: The success of the custom streamliners, sought to expand the market for diesel power by producing standardized locomotives under their Electro-Motive Corporation . In 1936, EMC's new factory started production of switch engines. In 1937, the factory started producing their new E series streamlined passenger locomotives, which would be upgraded with more reliable purpose-built engines in 1938. Seeing

5070-432: The throttle from notch 2 to notch 4 without stopping at notch 3. This feature was intended to prevent rough train handling due to abrupt power increases caused by rapid throttle motion ("throttle stripping", an operating rules violation on many railroads). Modern locomotives no longer have this restriction, as their control systems are able to smoothly modulate power and avoid sudden changes in train loading regardless of how

5148-479: The throttle setting, as determined by the engine driver and the speed at which the prime mover is running (see Control theory ). Locomotive power output, and therefore speed, is typically controlled by the engine driver using a stepped or "notched" throttle that produces binary -like electrical signals corresponding to throttle position. This basic design lends itself well to multiple unit (MU) operation by producing discrete conditions that assure that all units in

5226-562: The torque is low at idling speed, reaches a maximal value between 1,500 and 6,500 RPM, and then falls more or less sharply toward the redline. Below the RPM of maximal torque, the intake air velocity and thus mixing of air and fuel is not ideal. Above this speed several factors start to limit the torque, such as growing friction, the required time for closing the valves and combustion, and insufficient intake flow. Due to increasing vibration and heat, an external RPM limitation may also be installed. Power

5304-706: The torque is usually slightly lower. Synchronous motors can be used only at the AC source synchronous velocity. In modern applications, synchronous and induction motors with electronic control of the frequency are used, e.g., brushless DC electric motors . In this case, unless external limitations are applied, the maximum torque is achieved at low RPM. For example, the AC motor found in the Tesla Roadster (2008) produces near constant maximum torque from 0 to about 6000 RPM, while maximum power occurs at about 10000 RPM, long after torque begins to drop off. The Roadster's redline

5382-599: The transfer of technology agreement, the ALCO prototype was selected for production. However, even before the arrival of WDM-4 another type of diesel locomotive was imported from ALCO in 1957. This locomotive was classified as WDM-1 . However, WDM-1s were not selected for mass production because of having only one forward cab at one end, necessitating turntables for the driver's field of view. The WDM-4 locomotives were capable of hauling both freight and passenger trains, however they were primarily used on passenger service. The WDM-4

5460-451: The use of an internal combustion engine in a railway locomotive is the prototype designed by William Dent Priestman , which was examined by William Thomson, 1st Baron Kelvin in 1888 who described it as a " Priestman oil engine mounted upon a truck which is worked on a temporary line of rails to show the adaptation of a petroleum engine for locomotive purposes." In 1894, a 20 hp (15 kW) two-axle machine built by Priestman Brothers

5538-672: The world's first functional diesel–electric railcars were produced for the Königlich-Sächsische Staatseisenbahnen ( Royal Saxon State Railways ) by Waggonfabrik Rastatt with electric equipment from Brown, Boveri & Cie and diesel engines from Swiss Sulzer AG . They were classified as DET 1 and DET 2 ( de.wiki ). Because of a shortage of petrol products during World War I, they remained unused for regular service in Germany. In 1922, they were sold to Swiss Compagnie du Chemin de fer Régional du Val-de-Travers , where they were used in regular service up to

5616-473: Was 95 tonnes and the power was 883 kW (1,184 hp) with a maximum speed of 100 km/h (62 mph). Small numbers of prototype diesel locomotives were produced in a number of countries through the mid-1920s. One of the first domestically developed Diesel vehicles of China was the Dongfeng DMU (东风), produced in 1958 by CSR Sifang . Series production of China's first Diesel locomotive class,

5694-659: Was India's first EMD locomotive, and a model of GT16. These were the fastest locomotives in India until the arrival of WAP-3 engines. For some trains, WDM-4 engines had to double-head, as they normally could only pull 9 coaches. For the 18 car Rajdhani Express trains, this was common practice. WDM-4s hauled several high-profile express trains, including the Himgiri Express and Doon Express. WDM-4s also rarely hauled goods trains, and were primarily assigned to Mughalsarai (MGS). By late 1990s significant number were still in use, both in mainline and departmental duties. Of

5772-527: Was brought to high-speed mainline passenger service in late 1934, largely through the research and development efforts of General Motors dating back to the late 1920s and advances in lightweight car body design by the Budd Company . The economic recovery from World War II hastened the widespread adoption of diesel locomotives in many countries. They offered greater flexibility and performance than steam locomotives , as well as substantially lower operating and maintenance costs. The earliest recorded example of

5850-688: Was delivered from the United States to the railways of the Soviet Union. In 1947, the London, Midland and Scottish Railway (LMS) introduced the first of a pair of 1,600 hp (1,200 kW) Co-Co diesel–electric locomotives (later British Rail Class D16/1 ) for regular use in the United Kingdom, although British manufacturers such as Armstrong Whitworth had been exporting diesel locomotives since 1930. Fleet deliveries to British Railways, of other designs such as Class 20 and Class 31, began in 1957. Series production of diesel locomotives in Italy began in

5928-400: Was one of the principal design considerations that had to be solved in early diesel–electric locomotive development and, ultimately, led to the complex control systems in place on modern units. The prime mover's power output is primarily determined by its rotational speed ( RPM ) and fuel rate, which are regulated by a governor or similar mechanism. The governor is designed to react to both

6006-494: Was shown suitable for full-size passenger and freight service. Following their 1925 prototype, the AGEIR consortium produced 25 more units of 300 hp (220 kW) "60 ton" AGEIR boxcab switching locomotives between 1925 and 1928 for several New York City railroads, making them the first series-produced diesel locomotives. The consortium also produced seven twin-engine "100 ton" boxcabs and one hybrid trolley/battery unit with

6084-737: Was used on the Hull Docks . In 1896, an oil-engined railway locomotive was built for the Royal Arsenal in Woolwich , England, using an engine designed by Herbert Akroyd Stuart . It was not a diesel, because it used a hot-bulb engine (also known as a semi-diesel), but it was the precursor of the diesel. Rudolf Diesel considered using his engine for powering locomotives in his 1893 book Theorie und Konstruktion eines rationellen Wärmemotors zum Ersatz der Dampfmaschine und der heute bekannten Verbrennungsmotoren ( Theory and Construction of

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