Jump to content

Track gauge

From Wikipedia, the free encyclopedia
This is an old revision of this page, as edited by TheMightyOrb (talk | contribs) at 18:33, 4 August 2006 (→[[Iberian peninsula]]: Corrected metric conversion). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
Track gauge
By transport mode
By size (list)
Graphic list of track gauges
  Minimum
  Fifteen inch 381 mm (1 ft 3 in)
  Narrow
  600 mm 600 mm (1 ft 11+5⁄8 in)
Two foot 610 mm (2 ft)
Two foot three inch 686 mm (2 ft 3 in)
  750 mm 750 mm (2 ft 5+1⁄2 in)
Bosnian gauge 760 mm (2 ft 5+15⁄16 in)
Two foot six inch 762 mm (2 ft 6 in)
  Swedish three foot 891 mm (2 ft 11+3⁄32 in)
900 mm 900 mm (2 ft 11+7⁄16 in)
Three foot 914 mm (3 ft)
Italian metre 950 mm (3 ft 1+13⁄32 in)
  Metre 1,000 mm (3 ft 3+3⁄8 in)
  Three foot six inch 1,067 mm (3 ft 6 in)
  Four foot 1,219 mm (4 ft)
  Four foot six inch 1,372 mm (4 ft 6 in)
  1432 mm 1,432 mm (4 ft 8+3⁄8 in)
  Standard 1,435 mm (4 ft 8+1⁄2 in)
  Broad
  Italian broad gauge 1,445 mm (4 ft 8+7⁄8 in)
Dresden gauge 1,450 mm (4 ft 9+3⁄32 in)
  Leipzig gauge 1,458 mm (4 ft 9+13⁄32 in)
  Toronto gauge 1,495 mm (4 ft 10+7⁄8 in)
  1520 mm 1,520 mm (4 ft 11+27⁄32 in)
Five foot 1,524 mm (5 ft)
  Pennsylvania gauge 1,581 mm (5 ft 2+1⁄4 in)
Pennsylvania gauge 1,588 mm (5 ft 2+1⁄2 in)
Five foot three inch 1,600 mm (5 ft 3 in)
  Baltimore gauge 1,638 mm (5 ft 4+1⁄2 in)
  Iberian gauge 1,668 mm (5 ft 5+21⁄32 in)
Five foot six inch 1,676 mm (5 ft 6 in)
  Six foot 1,829 mm (6 ft)
  Brunel 2,140 mm (7 ft 1⁄4 in)
  Breitspurbahn 3,000 mm (9 ft 101⁄8 in)
Change of gauge
By location
World map, rail gauge by region

Rail gauge is the distance between the inner sides of the two parallel rails that make up a railway track. Sixty percent of the world's railways use a gauge of 1435 mm (4 ft 8½ in), which is known as the standard or international gauge. Gauges wider than standard gauge are called broad gauge, those smaller than standard narrow gauge. Some stretches of track are dual gauge, with three (or sometimes four) parallel rails in place of the usual two, to allow trains of two different gauges to share the same track. The term break-of-gauge refers to the situation at a place where different gauges meet.

History

Britain

Standard gauge was chosen for the first main-line railway, the LMR, by the British engineer George Stephenson, because it was already a de facto standard in the north of England where Stevenson had designed and built many tramlines and engines. Whatever the origin of the gauge it seemed to be a satisisfactory choice: not too narrow and not too wide.

Brunel on the Great Western Railway chose a broader gauge partly because it offered greater stability and capacity at high speed, but also because the Stephenson gauge was not scientifically selected. The Eastern Counties Railway chose five-foot gauge, but soon realised that the lack of compatibility was a mistake and changed to standard gauge.

In 1845 a British royal commission recommended adoption of standard gauge, and in the following year Parliament passed the Gauge Act, which required that new railways use standard gauge. Except for the Great Western Railway's broad gauge, few main-line British railways used a different gauge, and the Great Western was finally converted to standard gauge in 1892.

There were also a number of narrow gauge lines such as the following shown on the 1904 Railway Clearing House Railway Atlas:

United States

Originally a variety of gauges was used in the United States and Canada. Some, primarily in the northeast, used standard gauge; others did not, including gauges of up to 6 ft (1829 mm). Given the nation's recent independence from the United Kingdom, arguments based on British standards had little weight. Problems began as soon as railroads began to meet other railroads, and in much of the northeastern United States standard gauge was adopted. Most Southern states used 5 ft (1524 mm) gauge. Following the American Civil War, trade between the South and North grew and the break of gauge became a major economic nuisance. After considerable debate and planning, most of the southern rail network was converted from 5 ft (1524 mm) gauge to 4 ft 9 in (1448 mm) gauge, then the standard of the Pennsylvania Railroad, over two remarkable days beginning on May 31, 1886. The final conversion to standard gauge took place gradually as track was maintained. In modern uses certain isolated occurrences of non-standard gauges can still be found, such as the Bay Area Rapid Transit system in the San Francisco Bay Area, with 5 ft 6 in (1676 mm) gauge.

Russia

In the 19th century, Russia chose a broader gauge. It is widely believed that the choice was made for military reasons, to prevent potential invaders from using the Russian rail system. Others point out that no clear standard had emerged by 1842. Engineer Pavel Melnikov hired George Washington Whistler, a prominent American railroad engineer (and father of the artist James McNeill Whistler), to be a consultant on the building of Russia's first major railroad, the Moscow – St Petersburg line. The selection of 1.5 m gauge was recommended by German and Austrian engineers but not adopted: it was not the same as the 5 ft (1524 mm) gauge in common use in the southern United States at the time. Now Russia and most of the former Russian Empire, including the Baltic states, Ukraine, Belarus, the Caucasian and Central Asian republics, and Mongolia, have the Russian gauge of 1520 mm, 4 mm narrower than 5 ft (1524 mm), though rolling stock of both gauges is interchangeable in practice.

Finland

Finland, which was a Grand Duchy under Russia in the 19th century, uses 5 ft (1524 mm) gauge. Upon gaining independence in 1917, much thought was given to converting to standard gauge, but nothing came of it.

Iberian peninsula

The main railway networks of Spain and Portugal were constructed to gauges of six Castilian feet and five Portuguese feet. Later, following adoption of the metric system, these gauges were defined as 1674 mm (5 ft 5.59 in) and 1665 mm (5 ft 5.55 in) respectively. The gauges were sufficiently close to allow inter-operation of trains, and in recent years both have been adjusted to a common Iberic gauge (ancho ibérico in Spanish, bitola ibérica in Portuguese) of 1668 mm. Although it has been said that main reason for this non standard gauge would have been to bother any invasion attempts coming from France, in fact it was a technical decission, to increase stability in a mountainous country.[1]

Since the beginning of the 1990s new high-speed passenger lines in Spain have been built to the international standard gauge of 1435 mm, since it is intended that these lines will cross the French border and link to the European high-speed network. Although the 22 km from Tardienta to Huesca (part of a branch from the Madrid to Barcelona high-speed line) has been reconstructed as mixed Iberic and standard gauge, in general the interface between the two gauges in Spain is dealt with by means of gauge-changing installations, which can adjust the gauge of appropriately designed rolling stock on the move.

British Empire

Australia

In the 19th century, Australia's then three mainland states originally adopted standard gauge, but due to political differences a break of gauge 30 years in the future was created. After instigating a change to 5 ft 3 inch (1600 mm) agreed to by all, New South Wales reverted to standard gauge while Victoria and South Australia stayed with broad gauge. At least three different gauges are currently in use in Australia, and there is little prospect of full standardisation, though the main interstate routes are now standard gauge.

Canada

In Toronto the Toronto Transit Commission subways and streetcars use 1495 mm (4 ft 10 7/8 in) gauge, making their equipment incompatible with all other city transit systems. The two major transcontinental railways, Canadian National and Canadian Pacific both use the standard gauge. Until 1873 the Grand Trunk Railway [2] and the Champlain and St. Lawrence Railroad used 5ft 6in (1676 mm) gauge.

Hong Kong

In Hong Kong, the Mass Transit Railway uses 1432 mm gauge, 3 mm narrower than standard gauge. These trains can run on standard gauge only at low speeds. A new railway line across the Hong Kong-Zhuhai-Macau Bridge, an extension to the 1432 mm gauge Tung Chung Line, is a future option, but one which would require solving the problem of the 3 mm difference. This 3 mm difference should cause no more problems than the 4 mm difference causes between Russia and Finland, mentioned above.

Asia

Bangladesh, India, Pakistan and Sri Lanka inherited a diversity of rail gauges, of which 1676 mm was predominant. Indian Railways has adopted Project unigauge, which seeks to systematically convert most of its narrower gauge railways to the 1676 mm.

Afghanistan is in an interesting position, because it is at the crossroads of Asia and is virtually without railways. Should it decide to build any, the choice of gauge will be complicated by its being surrounded by three different gauges. Iran to the west uses standard gauge, as does China to the east; to the south, Pakistan uses 1676 mm gauge, while to the north, the central Asian republics of Turkmenia, Uzbekistan, and Tajikistan use 1520 mm gauge.

South America

Argentina and Chile use 1676 mm gauge, Brazil 1600 mm. Argentina and Peru use standard gauge.

Narrow gauge

In many areas a much narrower gauge was chosen. While narrow gauge generally cannot handle as much tonnage, it is less costly to construct, particularly in mountainous regions. Plantations such as for sugar cane and bananas are appropriately served by narrow gauges such as 2 ft (610 mm), as there is little through traffic to any other systems.

British Empire

Australia

Queensland, Tasmania, Western Australia and parts of South Australia adopted 3 ft 6 in (1067 mm) gauge to cover greater distances at lower costs. Most industrial Railways are built to 2ft gauge. At least three different rail gauges are currently in use throughout Australia, and there is little prospect of full standardisation.

Canada

Prince Edward Island used narrow gauge,then mixed or dual gauge until 1930, standard gauge until abandonment, and Newfoundland used narrow gauge. New Brunswick used narrow gauge until the 1880s, after which standard gauge prevailed. In all these cases the narrow gauge was 3ft 6in (1067 mm). The White Pass and Yukon Railroad uses 3ft 0in (914 mm) gauge.

New Zealand

New Zealand adopted narrow gauge 3 ft 6 in (1067 mm) due to the need to cross mountainous terrain in the country's interior. This terrain has necessitated a number of complicated engineering feats, notably the Raurimu Spiral. There are 1787 bridges and 150 tunnels in less than 4,000 km of track. Around 500 km of this track is electrified.

Asia

Southeast Asia

The railways of Southeast Asia, including Vietnam, Cambodia, Laos, Thailand, Myanmar and Malaysia are predominantly metre-gauge (1000 mm). The proposed ASEAN railway would be a standard-gauge or dual-gauge, using both metre and standard gauge regional railway networks, linking Singapore at the southern tip of the Malay Peninsula, through the Association of Southeast Asian Nations region Malaysia, Thailand, Laos and Vietnam to the standard-gauge railway network of the People's Republic of China. Indonesia's railways are predominantly 1067 mm.

Japan

Except for the high-speed Shinkansen lines, all of Japan Railway group's network is narrow-gauge, built at 3 ft 6 in (1067 mm). Some companies, such as Keisei Electric Railway, Keihin Electric Express Railway, Tokyo Metro's Ginza Line and Marunouchi line, use standard gauge. Keio Electric Railway, Toei Shinjuku Line and Tokyo and Hakodate tramways use 4 ft 6 in (1372 mm) gauge. There are some dual gauge lines which allow Shinkansen trains to travel on narrow-gauge branches.

Taiwan

Taiwan, which was ruled by Japan from 1895 to 1945, has 1067 mm lines of the systems under Taiwan Railway Administration. The new Taipei Rapid Transit System and the metro system under construction in Kaohsiung are standard gauge. The Taiwan High Speed Rail (HSR) sheduled to be completed in 2006 will also be standard gauge.

Africa

The railways of South Africa and many other African countries, including Angola, Botswana, Congo, Ghana, Mozambique, Namibia, Nigeria, Zambia and Zimbabwe, use 1067 mm gauge, sometimes referred to as Cape gauge. Kenya, Tanzania and Uganda have meter gauge (1000 mm) lines.

South America

Argentina, Bolivia, Brazil and Chile have meter gauge (1000 mm) lines. Colombia and Peru have 914 mm gauge lines.

Dual gauge and adjustable axles

Dual gauge allows trains of different gauges to share the same track. This can save considerable expense compared to using separate tracks for each gauge. There can, however, be many difficulties and speed restrictions. If the difference between the two gauges is large enough (say 1435 mm and 1067 mm), three-rail dual-gauge is possible, but if the difference is not large enough (say 1067 mm and 1000 mm), four-rail dual-gauge is necessary. Dual gauge helps the conversion from one gauge to another. Dual-gauge rail lines are used in the railway networks of Switzerland, Australia, Argentina, Brazil, North Korea, Tunisia and Vietnam.

Africa

  • 1000 mm and 1067 mm gauges are too close to allow three-rail dual gauge
    1000 mm and 1067 mm gauges are too close to allow three-rail dual gauge
  • 1000 mm and 1067 mm gauges can be used together, with four-rail dual gauge - note the third (useless) 1267mm gauge.
    1000 mm and 1067 mm gauges can be used together, with four-rail dual gauge - note the third (useless) 1267mm gauge.
  • 1000 mm and 1067 mm gauges can be used together with four-rail dual gauge, with bonus standard gauge
    1000 mm and 1067 mm gauges can be used together with four-rail dual gauge, with bonus standard gauge

Africa is particularly highly affected by gauge problems, where railways in adjacent countries meet.

Gauge rationalisation in Africa is facilitated since four-rail dual gauge of 1000mm and 1067mm contains a hidden gauge, which can be made to be standard gauge, 1435mm. The four-rail system reuses and doubles the effective strength of the old light rails, which might otherwise have only a low value reuse as fenceposts.

Variable gauge axles

Variable gauge axles, developed by the Talgo company and Construcciones y Auxiliar de Ferrocarriles company in Spain, enable trains to change gauge with only a few minutes spent in the gauge conversion process. The same system is also used between China and Central Asia, and Poland and Russia. Both China and Poland are standard gauge, while Central Asia and Russia are 1520 mm gauge.

Possible reasons why the VGA system is not more widely used could include:

  • Marketing and/or economics
  • Unfamiliarity.
  • Conservatism.
  • From standard to narrow gauge, not enough space between the wheels to accommodate the mechanism, especially to 3ft (914 mm) gauge.

Future

Further standardization of rail gauges seems likely, as individual countries seek to build inter-operable national networks, and international organizations seek to build macro-regional and continental networks. National projects include the Australian and Indian efforts mentioned above to create a uniform gauge in their national networks. The European Union has set out to develop inter-operable freight and passenger rail networks across the EU area, and is seeking to standardize not only track gauge, but also signaling and electrical power systems. EU funds have been dedicated to convert key railway lines in the Baltic states of Lithuania, Latvia, and Estonia from 1520 mm gauge to standard gauge, and to assist Spain and Portugal in the construction of high-speed rail lines to connect Iberian cities to one another and to the French high-speed lines. The EU has also developed plans for improved freight rail links between Spain, Portugal, and the rest of Europe.

All high-speed rail systems around the world have been built using or planning to use standard gauge, even in countries like Japan, Taiwan, Spain and Portugal where most of the country's existing rail lines use a different gauge. Once standard gauge high-speed networks exist, they may provide the impetus for gauge conversion of existing passenger lines to allow for interoperability. All high speed lines have adopted 25 kV AC as the standard electrification system.

The United Nations Economic and Social Commission for Asia and the Pacific (UNESCAP) is planning a Trans-Asian Railway that will link Europe and the Pacific, with a Northern Corridor from Europe to the Korean Peninsula, a Southern Corridor from Europe to Southeast Asia, and a North-South corridor from Northern Europe to the Persian Gulf. All the proposed corridors would encounter one or more breaks of gauge as they cross Asia. Current plans do not call for widespread gauge conversion; instead, mechanized facilities would be built to move shipping containers from train to train at the breaks of gauge.

Kenya-Uganda-Sudan proposal

A proposal was aired in October 2004 to build a high-speed electrified line to connect Kenya with southern Sudan. Kenya and Uganda use 1000 mm gauge, while Sudan uses 1067 mm gauge. By choosing standard gauge for the project, the gauge incompatibility is overcome. A bonus is that Egypt, further north, uses standard gauge. Since the existing narrow gauge track is quite likely of a "pioneer" standard, with sharp curves and low-capacity light rails, substantial reconstruction of the existing lines are needed, so gauge unification would be sensible.

Early origins of the standard gauge

There is a story that rail gauge was derived from the rutways created by war chariots used by Imperial Rome, which everyone else had to follow to preserve their wagon wheels, and because Julius Caesar set this width under Roman law so that vehicles could traverse Roman villages and towns without getting caught in stone ruts of differing widths. A problem with this story is that the Roman military did not use chariots in battle. However, an equal gauge is probably coincidence. Excavations at the buried cities of Pompeii and Herculaneum revealed ruts averaged 4 ft 9 in (1448 mm) center to center, with a gauge of 4 ft 6 in (1372 mm). The designers of both chariots and trams and trains were dealing with a similar issue, namely hauling wheeled vehicles behind draft animals.

A more likely theory why the 1,435 mm (4 ft 8+1⁄2 in) measurement was chosen is that it reflects vehicles with a 1524 mm (5 ft) outside gauge.

  • Ambrussum has some extant Roman chariot tracks.

List of rail gauges, by gauge

2150 mm (7ft 0¼in)

1945 mm (6ft 4⅝in)

1980 mm (6ft 2in)

1750 mm (5ft 8⅞in)

1676 mm (5ft 6in)

1668 mm (5ft 5½in)

1600 mm (5ft 3in)

5ft 2½in (1588 mm)

5ft 2¼in (1581 mm)

1575 mm (5ft 2in)

1524 mm (5ft)

1520 mm (4ft 11 27/32in)

1495 mm (4ft 10⅞in)

1470 mm (4ft 10in)

  • USA The Midwest - until after the Civil War

Standard gauge (4 ft 8½ in)(1435 mm)

1372mm

1100 mm (3ft 7⅓in)

1067 mm (3ft 6in)

1050 mm

1000 mm (3ft 3⅜in)

950 mm

914 mm (3ft)

900 mm (2ft 11 7/16in)

891 mm (3 swedish feet)

785 mm

762 mm (2ft 6in)

760 mm

750 mm

686mm (2ft 3in)

610 mm (2ft 0in)

600 mm (1ft 11.6in)

195.5 mm (7.5in), 381 mm (15in), 406.4 mm (16in), and 547.2 mm (18in)

These gauges were primarily used in mining operations and for park train rides. Since these track widths can, and do, support human passengers and tenable cargo, they are considered working narrow-gauge widths.

See also

Retrieved from "https://en.wikipedia.org/w/index.php?title=Track_gauge&oldid=67681131"