Diesel Multiple Units at sunset
The DEMU Transwa Prospector capable of up to 200 km h 124 mph provides passenger service between Perth and Kalgoorlie mining town.
A diesel multiple unit or DMU is a multi-unit being powered by diesel engines on a DMU requires no separate locomotive engines are incorporated in one or more carriages They can also be termed as a wagon or according railmotor country diesel units can be classified by their type of transmission DEMU diesel-electric, diesel mechanics DMMU or diesel hydraulic DHMU.
The diesel engine may be located above the frame in an engine compartment or under the floor driving commands can be at both ends, at one end, or none.
DMU are usually classified by the method of transmission of motive power to their citation needed wheels.
In a diesel-mechanical multiple unit DMMU the rotational energy of the motor is transmitted via a gearbox and the drive shaft directly to the wheels of the train, such as a car transmissions can be moved manually by the driver, as in the vast majority of British First generation DMU rail, but most applications are automatically changed gears.
In a diesel-hydraulic multiple unit, a hydraulic torque converter of a type of fluid coupling, acts as a transmission medium of the driving force of the diesel engine to rotate the wheels Some units comprise a hybrid transmission hydraulic and mechanical, usually returning to it at higher operating speeds, as this reduces engine speed and noise.
In modern Demus, such as the Bombardier family Traveling each car is fully autonomous and has its own motor, generator and electric motors 1 In older models, such as the British class rail 207 cars in the consist may be entirely non-powered or only have electric motors, obtaining an electric current from other cars of the train, who have a generator and motor.
A train made up of DMU scales well cars, as it allows a capacity of additional passengers to add together the driving force It also allows the passenger capacity to be adapted to the demand, and for trains to divide and joined in progress drive should not be based on the available power of the size and weight of the train, as each unit is able to move as the units are added, the available power to move trains increases the required amount EAD can have better acceleration capabilities, with more power axles, which makes them more suitable for roads with frequent stops spaced in relation to conventional locomotive configurations and non-motorized carts.
Distribution of the propulsion from cars is also reflected in a system that is less vulnerable to outages single point of failure Many DMU classes are able to operate with defective units still in the compound Due to the independent nature of diesel engines there is no need to run overhead power lines or electrified track which can result in lower costs of building the system.
These benefits must be weighed against the noise and vibration from the ground can be a problem with this type of train.
DMU were first introduced to Australia in the late mid-20th century for use on the quiet side lines that could not justify a locomotive Today, the towed service DMU are widely used in all the southern states Australia.
In Queensland, the DMU heritage are used on tourist trains and Savannahlander Gulflander.
Chinese manufactured CNR TANGSHAN DEMU was introduced in Bangladesh since May 25, 2013 DEMU is the first country in the suburban train service started its trial trip on the Chittagong-Fouzdarhat road.
P T INKA company owned built several types of DMU, some of which are operating in urban and suburban areas.
The Southrail or the main line of the Southern National Railway Philippines which travels south of the island of Luzon is one of the oldest railway lines in Asia and the world citation needed The Southrail railway Philippine national DMU uses Hyundai Rotem with second hand DMU eastern Japan Railway Company or JR east are Kiha Kiha 52 and 59 which is also known as Kogane Trains such as Hyundai Rotem DMU 52 Kiha and are often used to online suburban metro services, while Kiha 59 is primarily used for interprovincial Bicol services and sometimes also for the Metro commuter services.
Korail operates much DMU DHC hydraulic car Diesel, who made his debut for the Seoul Olympics in 1988, can reach speeds up to 170 km h and 106 mph serves Saemaul-ho trains citation needed.
The first major use of DMU UK was the Great Western Railway, which introduced its small but successful series of railcars GWR diesel-mechanical in 1934 LNER 4 and London Midland Railway and Scotland have also experimented with DMU in 1930, LMS on both its own system and that of its Irish subsidiary of the North, but the development was reduced by the First World war.
After nationalization, British railways revived the concept in the early 1950s, at the time there was an urgent need to move away from expensive steam traction has led to many experimental models using diesel propulsion and the multiple units DMU beginning proven, and in BR 1955 modernization Plan the construction of a large fleet was authorized BR These first generation DMU were built between 1956 and 1963 and class 121 for Bubble is still in use from 2015.
BR owners, the British government demanded that the contracts for the design and manufacture of new locomotives and rolling stock are distributed among many private companies, as well as workshops BR, while various BR regions established different specifications the result was a multitude of different types, one of which was.
Intercity units, which were more solidly built and shared many features with contemporary coaching stock towed They were built for express services on major roads in the Scottish, Northern and Eastern parts of quote West need.
In 1960, British Rail introduced its high speed Blue Pullman Demus 5 These were few and relatively short duration, 5 but they paved the way for British Rail InterCity very successful 125 or high units TGV HST, that were built between 1975 and 1982 to take over the most important express services on non-electrified routes 6 7 These 125 mph 201 km trains am running with a simplified electric car at each end and generally 7 to 9 intermediate trailer cars August 9 of initially classified as Demus, the trailer cars are very similar to loco-hauled vehicles, and electric cars were then reclassified as locomotives in class 43 September 8th They are widely used September 8th.
The popular 170 class was the best selling DMU last 10 years in the UK.
In the early 1980s, most of the first generation of surviving units have reached the end of their lifespan, leading to escalating maintenance costs, poor reliability and bad image for the railroad Solution second best was to convert some services back to transport locomotives, locomotives as spare and coaching towed equipment were available, but this has increased the effect of operating costs in the mid-80s, British rail began his so-called Sprinterisation program to replace most of the first generation DMU and many trains hauled by a locomotive with three new families of DMU.
Class 140-144 Pacer railcars ultra-low mechanical diesel units cost using the 4 wheel chassis and lightweight bus body, designed to provincial branch line and stopping services The oldest examples were retired service; citation needed.
Sprinter diesel-hydraulic DMU family are divided into three groups; Class 150 Sprinters to the commuter service branch line, class 153 155 156 Sprinters great for cross-country services, and class 158 159 Express units for secondary express services.
Diesel hydraulic units Networker, 165 Turbo network standard class and suburban Class 166 Express Network for distance commuter services resumed These other non-electric commuter services into London the citation needed.
Following the impact of the privatization of British Rail in the late 1990s, several other families diesel hydraulic DMU were citation needed.
Class 168 Clubman and class 170 171 Turbostar units, a development of earlier Networkers These are manufactured by Bombardier Transportation and are the most numerous and widespread post-privatization models The same basic design has been adapted for a variety of different types of use, from suburban secondary express services.
Coradia Class 175 were designed by Alstom as a rival to the 170 Turbostar, but purchased by First North Western.
Class 180 Adelante Alstom had a design for express services built exclusively for First Great Western.
Class 185 Desiro Siemens design introduced in the UK in 2006 for First TransPennine Express services.
Costa Rica has purchased several series railcars DMU of the former narrow gauge operator Apolo 2400 in Spain, which are managed in the commuter service 12 See rail transport in Costa Rica.
In the US only DMU FRA compliant systems are allowed on the rail corridors This cargo is due to the Federal Railway Administration set higher coupling strength requirements that European regulators, effectively banning the use of international rail lighter weight city European style DMU on US main railway line without timeshare with cargo operations or special exceptions FRA This greatly limited the development of the MISP in the United States as no other country requires compliant vehicles FRA much heavier, and no export market for quotation is required.
The Authority South Florida Regional Transportation used a bilevel Colorado Railcar DMU and coach made since October 2006 as a technology demonstrator on the 87-mile-long commuter train line Tri-Rail from Miami to West Palm Beach Florida in early 2007, three other DMU on two levels and a bi-level additional non-powered coach were acquired citation needed.
Since February 2009, TriMet uses FRA compliant Colorado Railcar DMU for its WES commuter rail service hours tip, a suburb suburban line between Beaverton and Wilsonville, Oregon The opening of the line was delayed for autumn 2008 to early 2009 due to delays in obtaining vehicles TriMet also has two former Alaska RR CDR as backup refurbished trains for when one or more Colorado Railcar DMU is outside citation needed service.
Also in the former BC Rail Oregon RDCs were used in the explorer excursion train Lewis and Clark from Portland to Astoria 13.
Sonoma Marin Area Rail Transit-also called SMART, Nippon Sharyo DMU will operate the same as those of Toronto on its route between San Rafael and Santa Rosa, California
Capital Metro uses Stadler GTW cars to operate a Capital MetroRail commuter line serving the Greater Austin area in Texas.
In Denton County, Texas DCTA also uses Stadler GTW cars to operate its A-Train Service DCTA got FRA the first round of the technology replacement cars to use these cars on the transport corridors assets 14.
NJ Transit operates the LINE river in Camden, New Jersey in Trenton, NJ every 15 minutes during peak hours and every 30 minutes at other times it uses the modified trains Stadler GTW one or two cars The line is classified as light rail because it uses imported European made DMU that violate FRA crash directives cars can not operate with rail freight service that shares the line, so the evening operating hours are limited to Saturday night this line carries more than 7,500 passengers on a weekday, exceeding expectations.
NCTD operates the Sprinter line using Desiro Classic DMU built by Siemens AG Opened in March 2008, the line runs every day for half an hour, with the exception of limitations in the mornings and evenings, Saturdays, Sundays and, the line passes from Oceanside, CA where the transfer is possible with Coaster commuter train service to San Diego in Escondido, California as the NJT river line, it is classified as light rail because of the use made of European DMU but do not carry a light rail frequency to more typical rail.
BART The expansion plan calls Ebart for service trains to diesel multiple units to be implemented from the Pittsburg Bay Point existing station The first phase of the expansion will continue east along Highway 4 corridor to the city of Antioch the plan includes an option for a station railway Avenue in Pittsburg future expansion in this direction could connect Ebart Service Oakley, Brentwood, Byron, and beyond the Stockton and Tracy DMU system was chosen as a cheaper alternative to the existing BART third rail design financing of this expansion was approved in April 2009 15.
Massachusetts Bay Transportation Authority in Boston announced plans in 2014 to acquire 30 DMU for use on the Fairmount line a MBTA commuter active rail line, but rarely serviced located in the Boston neighborhoods of Mattapan, Roxbury and Dorchester The first DMU proposal pilot allocated 240 million to acquire 16 DMUs FRA compliant, which were used to improve the frequencies along the catchment installed densely Fairmount line the cockpit received updates part MBTA another project associated with the broader CA T Big Dig emissions legislation mitigation projects 17 the MBTA has issued a request for proposals in 2014, but the possibility of the supply was never exercised in 2016, the authority has eliminated the allocation of 240 million for the implementation of the MISP pilot program Bonding authority ca program Hospital 2016 investment still exists in theory DMU purchases, but the RFP has since lapsed without the ubstantive s share despite an extension of several months.
The Metropolitan Transportation Los Angeles County Authority has approved a grant of 250,000 for MISP feasibility study for future transportation options for the region, July 5, 2006 Ara Najarian, Metro board member 18.
The Chicago commuter rail line, Metra is investigating the use of DMU on its newly proposed lines line STAR ITS They claim these DMU will have better acceleration, more fuel efficient, and seat more customers than the current diesel locomotive and double-decker cars that are currently in use 19.
Seattle Area - The Transport Agency regional public its Central Puget Sound Transit with the Regional Council of Puget Sound assessed the feasibility of both DMU and diesel locomotive technology to operate in the BNSF Eastside Corridor in response to a legislative request the state corridor trails BNSF Eastside of the city of Snohomish in north Renton in the south of the metropolitan area of its Transit does not intend to operate passenger rail service in the corridor Eastside BNSF, but committed limited funds to make capital improvements in case of another public or private operator proposes to operate the service 20.
Mat-Su Anchorage Area- As part of a joint project US Forest Service and ARRC USFS Forest Chugach Whistle Stop, a self-propelled car was purchased and delivered in spring 2009. The diesel multiple unit DMU may be available for service flexible demonstration during the winter months 21.
The Long Island Rail Road the way of the busiest commuter railway in the United States, studying the possibility of operating DMU on some of its roads less traveled in non-electrified territory on branches Montauk Greenport Port Jefferson and Oyster Bay, where operation of its current fleet C3 bi-level coaches pulled by locomotives DE30AC DM30AC is wasteful and inefficient.
DMU were studied for various transportation projects jointly proposed in the region, including Southwest LRT Riverview corridor and the Rush Line corridor, but were abandoned in favor of light rail using overhead cables or BRT Dan Patch Corridor is reconsidered for the study using DMU rather than diesel locomotive hauled coaches because of the curvature of the road and nearby residential areas.
Diesel multiple unit, diesel, multiple, unit.