Tram
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This article is about public transport vehicles running on rails. For other uses of "tram", see Tram (disambiguation).
"Streetcar" redirects here. For other uses, see Streetcar (disambiguation).
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Trams are usually lighter and shorter than conventional trains and rapid transit trains. However, the differences between these modes of public transportation are confusing. Some trams (for instance Tram-Trains) may also run on ordinary railway tracks, a tramway may be upgraded to a light rail or a rapid transit line, two urban tramways may be united to an interurban, etc.
Most trams today use electrical power, usually fed by a pantograph; in some cases by a third rail or trolley pole. If necessary, they may have several power systems. Certain types of cable car are also known as trams. Another power source is diesel; a few trams use electricity in the streets and diesel in more rural environments. Also steam and petrol (gasoline) have been used. Horse and mule driven trams do still occur.
Tramways are now included in the wider term "light rail", which also includes segregated systems. Some systems have both segregated and street-running sections, but are usually then referred to as trams, because it is the equipment for street-running which tends to be the decisive factor. Vehicles on wholly segregated light rail systems are generally called trains, although cases have been known of "trains" built for a segregated system being sold to new owners and becoming "trams".
A tram used on Tramlink Route 3 of the Croydon Tramlink owned by TfL in London
[edit] Etymology and terminology
Main article: Passenger rail terminology
Old tram stop on-demand notifier
The terms tram and tramway were originally (ca. 1500) Scottish words for the type of truck used in coal mines and the tracks on which they ran, probably derived from Middle Flemish tram "beam, handle of a barrow, bar, rung", a North Sea Germanic word of unknown origin meaning the beam or shaft of a barrow or sledge, also the barrow itself. Tram-car is attested from 1873.[1]Although tram and tramway have been adopted by many languages, they are not used universally in English, North Americans preferring trolley, trolleycar or streetcar. The term streetcar is first recorded in 1840. When electrification came, Americans began to speak of trolleycars or later, trolleys, believed to derive from the troller, a four-wheeled device that was dragged along dual overhead wires by a cable that connected the troller to the top of the car and collected electrical power from the overhead wires, sometimes simply strung, sometimes on a catenary.[2] The trolley pole, which supplanted the troller early on, is fitted to the top of the car and is spring-loaded in order to keep the trolley wheel or skate, at the top of the pole, firmly in contact with the overhead wire. The terms trolley pole and trolley wheel both derive from the troller.[3] Trams using trolley-pole current collection are normally powered through a single pole, grounded through the wheels and rails. The motor circuit is designed to allow electrical current to flow through the underframe.
Although this use of "trolley" for tram was not adopted in Europe, the term did appear with "trolleybus": a rubber-tyred vehicle without tracks which draws its power from overhead wires.
Modern trolley cars often use a metal shoe with a carbon insert instead of a trolley wheel, or have a pantograph. In North America, trams are sometimes called trolleys, even though strictly this may be incorrect: for example, cable cars, or conduit cars that draw power from an underground supply.
Tourist buses made to look like streetcars are sometimes called trolleys in the U.S. (tourist trolley). Open, low-speed segmented vehicles on rubber tires, generally used to ferry tourists short distances, can be called trams, for example on the Universal Studios backlot tour.
Electric buses, which use twin trolley poles (one for live current, one for return) but have wheels with tyres rolling on a hard surface rather than tracks, are called trolleybuses, trackless trolleys (particularly in the Northeastern U.S.), or sometimes (in the UK, as well as in Seattle and Vancouver) simply trolleys.
[edit] History
Main article: History of trams
Trams in Alexandria, Egypt (since 1860)
In 1883, Magnus Volk constructed his 2 feet (610 mm) gauge Volk's Electric Railway along the eastern seafront at Brighton, England. This two kilometer line, re-gauged to 2 feet 9 inches (840 mm) in 1884, remains in service to this day, and is the oldest operating electric tramway in the world. The first tram for permanent service with overhead lines was the Mödling and Hinterbrühl Tram in Austria. It started operating in October 1883, but was closed down in 1932.
The first electric street tramway in Britain, the Blackpool Tramway, was opened on 29 September 1885 using conduit collection along Blackpool Promenade. Since the closure of the Glasgow Corporation Tramways in 1962, this has been the only first-generation operational tramway in the UK.
Electric trams have run in Budapest since 1887, and this first line has now grown to be the busiest tram line of Europe, with the tram cars following each other at an interval of 60 seconds at rush hour. Bucharest and Belgrade[7] ran a regular service from 1894 and Sarajevo from 1885.[8][9][10]
[edit] Types of propulsion
[edit] Horse-drawn
A horse tramway in Danzig (now Gdańsk) in the late 19th century
Horse-drawn trams in Calcutta (now Kolkata), India—Life size model at City Centre arcade
Main article: Horsecar
These early forms of public transport developed out of industrial haulage routes or from the omnibus that first ran on public streets in the 1820s, using the newly invented iron or steel rail or 'tramway'. These were local versions of the stagecoach lines and picked up and dropped off passengers on a regular route, without the need to be pre-hired. Horsecars on tramlines were an improvement over the omnibus as the low rolling resistance of metal wheels on iron or steel rails (usually grooved from 1852 on), allowed the animals to haul a greater load for a given effort than the omnibus and gave a smoother ride. The horse-drawn streetcar combined the low cost, flexibility, and safety of animal power with the efficiency, smoothness, and all-weather capability of a rail right-of-way.[edit] Steam
Main article: Tram engine
Steam trams in Rockhampton, Queensland—note the small boiler at the front of the leading tram
The first mechanical trams were powered by steam. Generally, there were two types of steam tram. The first and most common had a small steam locomotive (called a tram engine in the UK) at the head of a line of one or more carriages, similar to a small train. Systems with such steam trams included Christchurch, New Zealand; Sydney, Australia; other city systems in New South Wales; Munich, Germany (from august 1883 on).[11] Steam tramways also were used on the suburban tramway lines around Milan; the last Gamba de Legn tramway ("Peg-Leg" in Milanese) ran on the Milan-Magenta-Castano Primo route in late 1958.The other style of steam tram had the steam engine in the body of the tram, referred to as a tram engine or steam dummy. The most notable system to adopt such trams was in Paris. French-designed steam trams also operated in Rockhampton, in the Australian state of Queensland between 1909 and 1939. Stockholm, Sweden, had a steam tram line at the island of Södermalm between 1887 and 1901. A major drawback of this style of tram was the limited space for the engine, so that these trams were usually underpowered.
[edit] Cable-pulled
Main article: Cable car (railway)
The next type of tram was the cable car, which sought to reduce labour costs and the hardship on animals. Cable cars are pulled along the track by a continuously moving cable running at a constant speed that individual cars grip and release to stop and start. The power to move the cable is provided at a site away from the actual operation. The first cable car line in the United States was tested in San Francisco, California, in 1873. The second city to operate cable trams was Dunedin in New Zealand, from 1881 to 1957. In Dresden, Germany, in 1901 an elevated suspended cable car following the Eugen Langen one-railed floating tram system started operating.Cable Cars operated on Highgate Hill in North London and Kennington to Brixton Hill In South London.
They also worked around "Upper Douglas" in the Isle of Man, Cable Car 72/73 being the sole survivor of the fleet.
Cable cars suffered from high infrastructure costs, since an expensive system of cables, pulleys, stationary engines and vault structures between the rails had to be provided. They also require strength and skill to operate, to avoid obstructions and other cable cars. The cable had to be dropped at particular locations and the cars coast, for example when crossing another cable line. Breaks and frays in the cable, which occurred frequently, required the complete cessation of services over a cable route, while the cable was repaired. After the development of electrically powered trams, the more costly cable car systems declined rapidly.
Cable cars were especially effective in hilly cities, because the cable laid in the tracks physically pulled the car up the hill at a strong, steady pace, as opposed to the low-powered steam dummies trying to chug up a hill at almost a crawl, or worse a horse-drawn trolley trying to pull a load up a hill.
This concept partially explains their survival in San Francisco. However, the most extensive cable system in the U.S. was in Chicago, a much flatter city. The largest cable system in the world, in the city of Melbourne, Victoria, Australia, had at its peak 592 trams running on 74 kilometres of track.
The San Francisco cable cars, though significantly reduced in number, continue to perform a regular transportation function, in addition to being a tourist attraction. A single line also survives in Wellington, New Zealand (rebuilt in 1979 as a funicular but still called the "Wellington Cable Car").
[edit] Hybrid funicular
Former second generation cable tractor, used between 1978 and 2005, assisting a tramcar on the cable section of the Opicina Tramway.
The Opicina Tramway in Trieste operates a hybrid funicular system where the trams are pushed uphill by cable tractors.[edit] Electric (trolley cars)
Main article: Trolley Car
See also: Conduit current collection
Fully restored 1920 Toronto streetcar
Old tram in Kiev, Ukraine
Electric trams in Sydney, Australia, circa 1920s
Multiple functioning experimental electric trams were exhibited at the 1884 World Cotton Centennial World's Fair in New Orleans, Louisiana, but they were not deemed good enough to replace the Lamm fireless engines then propelling the St. Charles Avenue Streetcar in that city.Electric trams (trolley cars) were first successfully installed in Saint Petersburg, Russia, invented and tested by Fyodor Pirotsky as early as 1880, and in Berlin in 1881 by Werner von Siemens and the company that still bears his name. Another was by John Joseph Wright, brother of the famous mining entrepreneur Whitaker Wright, in Toronto in 1883. Earlier installations proved difficult or unreliable. Siemens' line, for example, provided power through a live rail and a return rail, like a model train, limiting the voltage that could be used, and providing electric shocks to people and animals crossing the tracks.[12] Siemens later designed his own method of current collection, from an overhead wire, called the bow collector, and Thorold, Ontario, opened in 1887, and was considered quite successful at the time. While this line proved quite versatile as one of the earliest fully functional electric streetcar installations, it required horse-drawn support while climbing the Niagara Escarpment and for two months of the winter when hydroelectricity was not available. It continued in service in its original form into the 1950s. Electric trams were first tested in service in the United States in Richmond, Virginia, in 1888, in the Richmond Union Passenger Railway built by Frank J. Sprague, though the first commercial installation of an electric streetcar in the United States was built in 1884 in Cleveland, Ohio and operated for a period of one year by the East Cleveland Street Railway Company.[13] In 1904 the first double-decker tram in the world was put into operation in Hong Kong, and the Hong Kong Tramway still remains the only tramway in the world that uses exclusively double-decker trams.
[edit] Other power sources
The only petrol-driven tram of Stockholms Spårvägar, on line 19 in the 1920s
In some places, other forms of power were used to power the tram. Hastings and some other tramways, for example Stockholms Spårvägar in Sweden and some lines in Karachi, used petrol trams and Lytham St Annes used gas trams. Paris operated trams that were powered by compressed air using the Mekarski system. In New York City some minor lines used storage batteries; a longer battery-operated tramway line ran from Milan to Bergamo (about 60 km) during the 1950s.Galveston Island Trolley in Texas operates diesel trams due to the city's hurricane-prone location, which would result in frequent damage to an electrical supply system.
[edit] Design
[edit] Low floor
For more details on this topic, see Low-floor tram.
Entirely low-floor Škoda ForCity in Prague
The latest generation of light rail vehicles is of partial or fully low-floor design, with the floor 300 to 360 mm (11.8 to 14.2 in) above top of rail, a capability not found in older vehicles. This allows them to load passengers, including those in wheelchairs, directly from low-rise platforms that are not much more than raised footpaths/sidewalks. This satisfies requirements to provide access to disabled passengers without using expensive wheelchair lifts, while at the same time making boarding faster and easier for other passengers.
Two Trams in Braunschweig, Germany. The left one is an 1981 high-floor tram, the right one a 2007 low-floor
Various companies have developed particular low-floor designs, varying from part-low-floor (with internal steps between the low-floor section and the high-floor sections over the bogies), e.g. Citytram[14] and Siemens S70, to 100% low-floor, where the floor passes through a corridor between the drive wheels, thus maintaining a relatively constant (stepless) level from end to end of the tram. However, prior to the introduction of the Škoda ForCity,[citation needed] this carried the mechanical penalty of requiring bogies to be fixed and unable to pivot (except for less than 5 degrees in some trams). This creates undue wear on the tracks and wheels. However, passengers appreciate the ease of boarding and alighting from low-floor trams and moving about inside 100% low-floor trams. Passenger satisfaction with low-floor trams is high.[15] Low-floor trams are now running in many cities around the world, including Milan, Dublin, Prague, Riga, Melbourne, Hiroshima, Houston, Vienna, Istanbul and Strasbourg.[edit] Articulated
Articulated tram in Barcelona
Articulated trams, invented and first used by the Boston Elevated Railway in 1912-13[16] at a total length of about twelve meters long (40 ft) for each pioneering example of twin-section articulated tram car, have two or more body sections, connected by flexible joints and a round platform at their pivoting midsection(s). Like articulated buses, they have increased passenger capacity. In practice, these trams can be up to 53 metres (174 ft) long[17] (such as in Budapest, Hungary),[18] while a regular tram has to be much shorter. With this type, the articulation is normally suspended between carbody sections. In the Škoda ForCity, which is the world's first 100% low floor tram with pivoting bogies, a Jacobs bogie supports the articulation between the two or more carbody sections. An articulated tram may be low-floor variety or high (regular) floor variety. Newer model trams may be up to 72 meters long and carry 510 passengers at a comfortable 4 passengers/m2. At crush loadings this would be even higher.[19][edit] Double decker
Double decker trams operate in Alexandria, Blackpool and Hong Kong.[edit] Tram-train
Main article: Tram-train
Tram-train operation uses vehicles such as the Flexity Link and Regio-Citadis, which are suited for use on urban tram lines and also meet the necessary indication, power, and strength requirements for operation on main-line railways. This allows passengers to travel from suburban areas into city-centre destinations without having to change from a train to a tram.It has been primarily developed in Germanic countries, in particular Germany and Switzerland. Karlsruhe is a notable pioneer of the tram-train.
[edit] Cargo trams
CarGoTram run by Volkswagen in Dresden, Germany on a section of grassed track. It delivers parts to the Transparent Factory.
Goods have been carried on rail vehicles through the streets, particularly near docks and steelworks, since the 19th century (most evident on the Weymouth Harbour Tramway in Weymouth, Dorset[20]), and some Belgian vicinal tramway routes were used to haul timber. Several of the US interurbans carried freight. At the turn of the 21st century, a new interest has arisen in using urban tramway systems to transport goods. The motivation now is to reduce air pollution, traffic congestion and damage to road surfaces in city centres. Dresden has a regular CarGoTram service, run by the world's longest tram trainsets (59.4 metres (195 ft)), carrying car parts across the city centre to its Volkswagen factory.[21] Vienna and Zürich use trams as mobile recycling depots. Kislovodsk had a freight-only tram system comprising one line which was used exclusively to deliver bottled Narzan mineral water to the railway station.[22]In the spring of 2007, Amsterdam piloted a cargo tram operation, aiming to reduce particulate pollution by 20% by halving the number of lorries—currently 5,000—unloading in the inner city during the permitted timeframe from 07:00 till 10:30. The pilot, operated by City Cargo Amsterdam, involved two cargo trams, operating from a distribution centre and delivering to a "hub" where electric trucks delivered to the final destination.
The trial was successful, releasing an intended investment of €100 million in a fleet of 52 cargo trams distributing from four peripheral "cross docks" to 15 inner-city hubs by 2012. These specially built vehicles would be 30 feet (9.1 m) long with 12 axles and a payload of 30 tons. On weekdays, trams are planned to make 4 deliveries per hour between 7 a.m. and 11 a.m. and two per hour between 11 a.m. and 11 p.m. With each unloading operation taking on average 10 minutes, this means that each site would be active for 40 minutes out of each hour during the morning rush hour. In early 2009 the scheme was suspended owing to the financial crisis impeding fund-raising.[23]
[edit] Hearse-tram
Specially appointed hearse trams were used for funerals in Milan, Italy, from the 1880s (initially horse-drawn) to the 1920s. The main cemeteries, Cimitero Monumentale and Cimitero Maggiore, included funeral tram stations. Additional funeral stations were located at Piazza Firenze and at Porta Romana.[24]In the mid-1940s at least one special hearse tram was used in Turin, Italy. It was introduced due to the wartime shortage of automotive fuel.[25]
[edit] Tramway operation
There are two main types of Tramways, the classic tramway build in the early 20th century with the tram system operating in mixed traffic and the latter type which is most often associated with the tram system having it own right of way. Tram systems that have their own right of way are often call Light Rail but this does not always hold true. Though these two systems have difference in their operation their equipment is much the same.Infrastructure and equipment
Tram stop
Main article: Tram stop
Controls
Main article: Tram controls
Track
Main article: Tramway track
Power supply
[edit] Tram and light-rail transit systems around the world
Double-decker trams continue to run in Hong Kong.
Main article: Tram and light-rail transit systems
Throughout the world there are many tram systems; some dating from the late 19th or early 20th centuries. However a large number of the old systems were closed during the mid-20th century because of such perceived drawbacks as route inflexibility and maintenance expense. This was especially the case in North American, British, French and other West European cities. Some traditional tram systems did however survive and remain operating much as when first built over a century ago. In the past twenty years their numbers have been augmented by modern tramway or light rail systems in cities that had discarded this form of transport.[edit] Popularity
Tramways with tramcars (British English) or street railways with streetcars (American English) were common throughout the industrialised world in the late 19th and early 20th centuries but they had disappeared from most British, Canadian, French and U.S. cities by the mid-20th century.[26]By contrast, trams in parts of continental Europe continued to be used by many cities, although there were contractions in some countries, including the Netherlands.[27]
Since 1980 trams have returned to favour in many places, partly because their tendency to dominate the highway, formerly seen as a disadvantage, is now considered to be a merit. New systems have been built in the United States, Great Britain, Ireland, France and many other countries.
[edit] Largest tram systems
The Silesian Interurbans in Poland and the Trams in Melbourne, Australia, are claimed to be the largest tram networks in the world. Before its decline the BVG in Berlin operated a very large network with 634 km of route. During a period in the 1980s the world's largest tram system was in Leningrad, USSR, being included in Guinness World Records.The largest single tram line in the world is the Belgian Coast tram, whichs runs almost the entire length of the Belgian coast. Other large systems include (but not limited to) Vienna, Leipzig, Prague, Kiev, Warsaw, Amsterdam, Brussels,Basel, Zurich, Bucharest and Toronto.
Until the system started to be converted to trolleybus (and later bus) in the 1930s, the first-generation London network was also one of the world's largest, with 526 km (327 mi) of route in 1934.[28] While the largest streetcar network in the world used to be located in Chicago, with over 850 kilometres (530 mi) of track,[29] all of it was converted to bus service by the late 1950s.
[edit] Asia
Main article: Trams in Asia
Tram running on Kolkata Road, India
Tramway systems were well established in the Asian region at the start of the 20th century, but started a steady decline during the mid to late 30s. The 1960s marked the end of its dominance in public transportation with most major systems closed and the equipment and rails sold for scrap; however, some extensive original lines still remain in service in Hong Kong and Japan. In recent years there has been renewed interest in the tram with modern systems being built in Japan, the Philippines, and South Korea.The first Japanese tram line was inaugurated in 1895 as the Kyoto Electric Railroad. The tram reached its zenith in 1932 when 82 rail companies operated 1,479 kilometers of track in 65 cities. The tram declined in popularity through the remaining years of the 30s, a trend that was accelerated by the damages of the War and continued through the Occupation and rebuilding years. During the 1960s many of the remaining operational tramways were shut down and dismantled in favor of auto, bus, and rapid rail service; however, when one compares the number of operational lines that survived this era to their American counterparts, they can be defined as quite extensive.
[edit] Europe
New Berlin MetroTram
Main article: Trams in Europe
In many European cities much tramway infrastructure was lost in the mid-20th century, though not always on the same scale as in other parts of the world such as North America. Most of Eastern Europe retained tramway systems until recent years but some cities are now reconsidering their transport priorities. In contrast, some Western European cities are rehabilitating, upgrading, expanding and reconstructing their old tramway lines. Many Western European towns and cities are also building new tramway lines.[edit] North America
Streetcars in Toronto operate the largest such system in North America.
Main article: Streetcars in North America
In North America trams are generally known as streetcars or trolleys; the term tram is more likely to be understood as a tourist trolley, an aerial tramway, or a people-mover.In some North American cities, streetcar lines were largely torn up in the mid-20th century for a variety of financial, technological and social reasons. (See also the Great American Streetcar Scandal.) Exceptions include New Orleans, Tampa, Newark, Seattle, Philadelphia (with a much smaller network than once had existed), and San Francisco. American cities, such as Memphis, Tacoma, Washington, D.C., Portland, Seattle, and Detroit are beginning to rebuild or add streetcar systems. Pittsburgh kept most of its streetcar system serving the city and many suburbs until January 27, 1967, making it the longest-lasting large-network U.S. streetcar system. In the late 20th century, several cities installed light rail systems, in part along the same corridor as the old streetcars.
Toronto currently has the largest streetcar system in the Americas in terms of track length and ridership, operated by the Toronto Transit Commission. It is the only streetcar system existing in Canada, not including the light rail systems that some Canadian cities currently operate. Toronto's system uses Canadian Light Rail Vehicles and Articulated Light Rail Vehicles, after a history of using PCCs, Peter Witt cars, and horse-drawn carriages. The system is currently proposing to replace its current fleet with Bombardier's Flexity Outlook models, which is also used in some European tram systems. Streetcars once existed in Edmonton and Calgary, but both cities have since converted their systems to support light rail vehicles instead. Streetcars also once existed in Ottawa, Montreal, Kitchener and Hamilton. Some cities have restored their old streetcars and run them as a heritage feature for tourists, like the Vancouver Downtown Historic Railway.
[edit] Australia and New Zealand
A heritage H-Class model (foreground) and modern Flexity tram (background) in Glenelg, Adelaide
Main articles: Trams in Australia and Trams in New Zealand
In Australasia, trams are used extensively only in Melbourne, and to a lesser extent, Adelaide, all other major cities having largely dismantled their networks by the 1970s. Sydney reintroduced its tram in 1997 as a modern system (Metro Light Rail), while Ballarat, Christchurch and Perth reintroduced their trams as heritage systems. Bendigo had a heritage system for a while which has recently been upgraded to a simple public transport system through an increase in frequency.A distinctive feature of many Australasian trams was the early use of a lowered central section between bogies (wheel-sets). This was intended to make passenger access easier, by reducing the number of steps required to reach the inside of the vehicle. It is believed that the design first originated in Christchurch in the first decade of the 20th century. Cars with this design feature were frequently referred to as "drop-centres". Trams built since the 1970s have had conventional high or low floors.
The trams made by Boon & Co. of Christchurch, New Zealand in 1906–07 for use in Christchurch may have been the first with this feature; they were referred to as drop-centres or Boon cars. Trams for Christchurch and Wellington built in the 1920s with an enclosed section at each end and an open-sided middle section were also known as Boon cars, but did not have the drop-centre.
[edit] South America
Puerto Madero Tramway in Buenos Aires
Buenos Aires in Argentina had once one of the most extensive tramway networks in the world with over 857 km (535 mi) of track, most of it dismantled during the 1960s in favor of bus transportation. Now slowly coming back, the 2 km Puerto Madero Tramway running in the Puerto Madero district is spearheading the move with extensions to Retiro station and La Boca in the planning stages. Another line, the PreMetro line E2 system feeding the Line E of the Buenos Aires Subway has been operating for the past few years on the outskirts of Buenos Aires, and a unique leisure "Tren de la Costa", an artery that stretches for 15 kilometres by the River Plate, from Olivos to the village of Tigre has also been running in Buenos Aires.Also in Argentina, in the city Mendoza, a new tramway line is in construction, the Metrotranvía of Mendoza, which will have a route of 12.5 km and will link five districts of the Greater Mendoza conurbation. The opening of the system is scheduled for 2011. Also in Medellín, Colombia, there is a tram line under construction and the opening schedule is for December 2011.[30]
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