SA3 coupler
Encyclopedia
Coupling (railway)
A coupling is a mechanism for connecting rolling stock in a train. The design of the coupler is standard, and is almost as important as the railway gauge, since flexibility and convenience are maximised if all rolling stock can be coupled together.The equipment that connects the couplings to the...
used mainly, but not exclusively, in Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
and other states of the former Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
.
Railways in Russia used European (British) buffers and couplings from their inception. These couplings had three main limitations. Firstly the load was limited. Secondly, the couplings were not automatic like the North American AAR. Thirdly, the buffers could get buffer-locked and cause accidents. Advantages and disadvantages of these couplings are intermediate between AAR couplers and Scharfenberg couplers.
It took a while to find a replacement. One option was to copy the AAR coupling, as Japan (1922), Australia (1915) and other countries were starting to do, or to devise something else. The Soviets were not afraid to copy, as they had imported many engines and engineers during the various five year plans. In the end they chose the SA3, although implementation was delayed by World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Experimentation
In the late 1920s, the UIC had established a working group for the replacement of the chain link coupler, which restricts the efficiency of freight railroads in a major way. Many railroads ran prototypes. In Germany, coal trains with Scharfenberg couplers yielded unfavourable results in winter weather, other railroads did similar tests. But the UIC was not able to agree on one replacement. This failure of the UIC, which hampers freight operation in Europe even today, led to the decision by the Soviet Union to move forward without a standard being achieved in the talks.The coupler was named SA-3. This type of coupler was standardized for the railways in the Soviet Union after World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
.
Further tests were carried out in the 1950s.
Operation of this coupler
The benefit of this coupler: About 5000–6000 t (11,023,113.1–13,227,735.7 lb) could be hauled. This was a good impulse for the Soviet industries, because the transport capacities were doubled.Helper locomotives at the end of the train are rarely used in the countries of the former Soviet Union. The load of the freight per train is not as heavy as on American railways. This is due to the 3 kV DC electrification system
Railway electrification system
A railway electrification system supplies electrical energy to railway locomotives and multiple units as well as trams so that they can operate without having an on-board prime mover. There are several different electrification systems in use throughout the world...
. Most of the catenary in the former Soviet Union is fed with 3 kV DC and its construction (except some lines around Moscow) does not allow more than 6000 kW per electric section (one locomotive has power effort from 3000 kW).
Although the SA-3 coupler is primarily used in the countries of the former Soviet Union, they are visible every day at the transshipping stations, at the eastern borders of the European Union (Poland, Slovakia and Hungary). Since bogie-changing
Bogie exchange
Bogie exchange is a system for operating railway wagons on two or more gauges to overcome difference in the track gauge. To perform a bogie exchange, a car is converted from one gauge to another by removing the chassis containing the wheels and axles of the car, and installing a new chassis with...
technology has progressed, this allows for cars with SA-3 coupler to regularly operate on the standard gauge tracks. A special converter car is inserted between standard and broad gauge cars for this operation, with different couplers (SA-3 and standard) on either end. Although these coupling freight cars (light blue coloured at the Slovak Cargo Railways) have room for cargo, they are always operated empty.
If the vehicle fitted with the SA3 retains its buffers, then a special adapter allows that vehicle to couple to another vehicle fitted with buffers and chains, provided that the buffers have the same spacing or gauge. This appears to be done in Iran.
On the Uzhhorod - Košice broad gauge track
Uzhhorod - Košice broad gauge track
The Uzhhorod – Košice broad gauge track is a single track railway mostly in eastern Slovakia, which is used especially for iron ore transportation from Ukraine to the steel factory near Košice....
between Košice
Košice
Košice is a city in eastern Slovakia. It is situated on the river Hornád at the eastern reaches of the Slovak Ore Mountains, near the border with Hungary...
and Uzhhorod
Uzhhorod
Uzhhorod or Uzhgorod is a city located in western Ukraine, at the border with Slovakia and near the border with Hungary. It is the administrative center of the Zakarpattia Oblast , as well as the administrative center of the surrounding Uzhhorodskyi Raion within the oblast...
, Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
, of which the major part is on Slovakian territory, SA3 couplings are used exclusively. The railway is used for ore and coal transports from Kryvyi Rih
Kryvyi Rih
Kryvyi Rih or Krivoy Rog is a city in central Ukraine. It is situated in Dnipropetrovsk Oblast, to the southwest of the oblast's administrative center, Dnipropetrovsk, at the confluence of the Inhulets and Saksahan rivers...
, Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
to the US Steel mill in Košice
U. S. Steel Košice, s.r.o.
U. S. Steel Košice, s.r.o. is a steel company located in Košice, Slovakia.In November 2000, the ownership of the complete metallurgical operation of former Východoslovenské železiarne Košice was transferred to the United States Steel Corporation....
and coal to the power plant of Vojany
Vojany
Vojany is a village and municipality in Michalovce District in the Kosice Region of eastern Slovakia.-Geography:The village lies at an altitude of 102 metres and covers an area of 10.923 km². The municipality has a population of about 830 people....
. In 2008, this line is to be extended into Austria.
In addition, the heavy iron ore trains on the Swedish Malmbanan
Malmbanan
The Iron Ore Line is a long railway line between Riksgränsen and Boden in Norrbotten County, Sweden. The line contains two branches, from Kiruna to Svappavaara and from Gällivare to Koskullskulle. The term is often colloquially used to also include the Ofoten Line, from Riksgränsen to Narvik in...
began to use SA3 couplings in 1969 after problems with snapping chain couplers and a need for ever increasing capacity with higher train weights. Today, IORE
IORE
Iore, often stylized IORE, is a class of 26 electric locomotives built by Adtranz and its successor Bombardier Transportation for the Swedish mining company LKAB's railway division Malmtrafik. The class is a variation of Adtranz's Octeon modular product platform, thus related to Bombardier's later...
locomotives haul 68 120 tonnes (264,554.7 lb) gondolas
Gondola (rail)
In railroad terminology, a gondola is an open-top type of rolling stock that is used for carrying loose bulk materials. Because of its low side walls, gondolas are used to carry either very dense material, such as steel plates or coils, or bulky items such as prefabricated pieces of rail...
with a total weight of over 8000 tonnes (17,636,981 lb) over gradients of 10 per-mille (1%) in harsh weather conditions, from the LKAB
LKAB
LKAB is a Swedish mining company. The company mines iron ore at Kiruna and at Malmberget in northern Sweden. The company was established in 1890, and has been 100% state-owned since the 1950s...
mine in Kiruna
Kiruna
Kiruna is the northernmost city in Sweden, situated in Lapland province, with 18,154 inhabitants in 2005. It is the seat of Kiruna Municipality Kiruna (Northern Sami: Giron, Finnish: Kiiruna) is the northernmost city in Sweden, situated in Lapland province, with 18,154 inhabitants in 2005. It is...
to the ice-free harbour of Narvik
Narvik
is the third largest city and municipality in Nordland county, Norway by population. Narvik is located on the shores of the Narvik Fjord . The municipality is part of the Ofoten traditional region of North Norway, inside the arctic circle...
, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
using couplings of the SA3 type without any problem. The earlier SJ Dm3
SJ Dm3
Dm and Dm3 is a series of locomotives used by Statens Järnvägar and later Malmtafik i Kiruna for pulling iron ore trains on Malmbanan in Sweden and Ofotbanen in Norway. A total of 39 double-locomotives were delivered between 1953 and 1971, built by ASEA. A further 19 center locomotives were...
locomotives have buffers fitted, therefore they can couple with cars
Railroad car
A railroad car or railway vehicle , also known as a bogie in Indian English, is a vehicle on a rail transport system that is used for the carrying of cargo or passengers. Cars can be coupled together into a train and hauled by one or more locomotives...
(or locomotive
Locomotive
A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
s for transportation purposes) with chainlink coupler.
Worldwide, the heaviest trains
Heaviest trains
The heaviest trains in the world are freight trains hauling bulk commodities such as coal and iron ore. One might distinguish between regular operations, and occasional record breaking runs...
, of around 30000 tonnes (66,138,678.7 lb), operate with AAR coupling. The SA3 is not used for such loads—the European single locomotive haulage record stands at 12000 tonnes (26,455,471.5 lb), by a British Rail Class 59
British Rail Class 59
The Class 59 Co-Co diesel locomotives were built and introduced between 1985 and 1995 by Electro-Motive Division of General Motors for private British companies, initially Foster Yeoman...
. New railways are mostly electrified at 25 kV AC
25 kV AC
The 25 kV Alternating current railway electrification system is commonly used in railways worldwide, especially for high-speed rail.-Overview:This electrification system is ideal for railways that cover long distances and/or carry heavy traffic...
, which allows higher power than 3 kV DC, so records may yet be challenged. New international links may also see the SA3 and AAR coupling meet and it is unknown how this break-of-gauge
Break-of-gauge
With railways, a break-of-gauge occurs where a line of one gauge meets a line of a different gauge. Trains and rolling stock cannot run through without some form of conversion between gauges, and freight and passengers must otherwise be transloaded...
will be resolved.
Future
The new European Automatic Center Coupler (C-AKvC-AKv
The C-AKv coupler is a fully automatic center coupler for railway cars, which is designed as a replacement for the European buffers-and-chain coupler. Its profile is based on the Willison profile of the Russian SA3 coupler...
) has been based on this coupler, with the extended features of automatic brake and electric couplings. It also has vertical stability added, so that the coupling cannot fall down and damage the tracks or cause a derailment. It is compatible with the standard SA3 coupler and will have buffers needed for use with the standard chain couplings under the long transition period. The electric plugs would be most useful with electronically controlled pneumatic brakes
Electronically controlled pneumatic brakes
Electronically controlled pneumatic brakes are a type of modern railway braking system which offer improved performance compared to traditional pneumatic brakes.- Overview :...
.
Usage
The former Soviet Union:Armenia
Armenia
Armenia , officially the Republic of Armenia , is a landlocked mountainous country in the Caucasus region of Eurasia...
, Armenian Railway
Armenian Railway
The Armenian Railways are the national rail operator in Armenia. The , gauge network is electrified at 3 kV DC.The operating environment has deteriorated since the collapse of the Soviet Union...
Azerbaijan
Azerbaijan
Azerbaijan , officially the Republic of Azerbaijan is the largest country in the Caucasus region of Eurasia. Located at the crossroads of Western Asia and Eastern Europe, it is bounded by the Caspian Sea to the east, Russia to the north, Georgia to the northwest, Armenia to the west, and Iran to...
, Rail transport in Azerbaijan Belarus
Belarus
Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,...
, Rail transport in Belarus
Rail transport in Belarus
Rail transport in Belarus is owned by the national rail company BŽD / BČ . The railway network consists of 5,512 km, its gauge is 1,520 mm and 874 km are electrified.-History:...
Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...
, Rail transport in Estonia
Rail transport in Estonia
The rail transport system in Estonia consists of circa of railway lines, of which are currently in public use. The infrastructure of the railway network is mostly owned by the state and is regulated and surveyed by the Estonian Railway Inspectorate ....
Georgia
Georgia (country)
Georgia is a sovereign state in the Caucasus region of Eurasia. Located at the crossroads of Western Asia and Eastern Europe, it is bounded to the west by the Black Sea, to the north by Russia, to the southwest by Turkey, to the south by Armenia, and to the southeast by Azerbaijan. The capital of...
, Georgian Railway
Georgian Railway
Georgian Railway LLC is the national rail company of the country of Georgia.A vital artery linking the Black Sea and the Caspian Sea, it sits on the shortest route between Europe and Central Asia...
Kazakhstan
Kazakhstan
Kazakhstan , officially the Republic of Kazakhstan, is a transcontinental country in Central Asia and Eastern Europe. Ranked as the ninth largest country in the world, it is also the world's largest landlocked country; its territory of is greater than Western Europe...
, Qazaqstan Temir Zholy
Qazaqstan Temir Zholy
Kazakhstan Temir Zholy , also National Company Kazakhstan Temir Zholy, is the national railway company of Kazakhstan.-Organization:...
Kyrgyzstan
Kyrgyzstan
Kyrgyzstan , officially the Kyrgyz Republic is one of the world's six independent Turkic states . Located in Central Asia, landlocked and mountainous, Kyrgyzstan is bordered by Kazakhstan to the north, Uzbekistan to the west, Tajikistan to the southwest and China to the east...
, Kyrgyz Railway
Kyrgyz Railway
The Kyrgyz Railway , presided by Nariman Tuleyev, is the national railway developer of Kyrgyzstan.Kyrgyz Railway operates about 320 km of single track lines . After the Soviet Union broke up, Kyrgyz Railways obtained 2,500 freight cars, 450 passenger cars and 50 locomotives from the Soviet...
Latvia
Latvia
Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...
, Rail transport in Latvia
Rail transport in Latvia
Rail transport in Latvia is done on Russian gauge. The main railway company is Latvijas dzelzceļš.Historically Latvia had lot of different rail gauges, most notably standard gauge and narrow gauge.- Rail links with adjacent countries :...
Lithuania
Lithuania
Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...
, Lithuanian Railways
Lithuanian Railways
Lithuanian Railways is the national, state-owned railway company of Lithuania. It operates all the railway lines in the country.Lithuanian Railways' main network consists of 1749 km of broad gauge railway of which 122 km are electrified. They also operate 22 km of standard gauge...
Moldova
Moldova
Moldova , officially the Republic of Moldova is a landlocked state in Eastern Europe, located between Romania to the West and Ukraine to the North, East and South. It declared itself an independent state with the same boundaries as the preceding Moldavian Soviet Socialist Republic in 1991, as part...
, Calea Ferată din Moldova
Calea Ferată din Moldova
CFM is the only railway operator in the Republic of Moldova, that is responsible for passenger and cargo transportation, as well as the railway infrastructure maintenance, within the country. It is the successor of MZhD, a subdivision of the USSR railway...
Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, Russian Railways
Russian Railways
The Russian Railways , is the government owned national rail carrier of the Russian Federation, headquartered in Moscow. The Russian Railways operate over of common carrier routes as well as a few hundred kilometers of industrial routes, making it the second largest network in the world exceeded...
Turkmenistan
Turkmenistan
Turkmenistan , formerly also known as Turkmenia is one of the Turkic states in Central Asia. Until 1991, it was a constituent republic of the Soviet Union, the Turkmen Soviet Socialist Republic . Turkmenistan is one of the six independent Turkic states...
, Rail transport in Turkmenistan Tajikistan
Tajikistan
Tajikistan , officially the Republic of Tajikistan , is a mountainous landlocked country in Central Asia. Afghanistan borders it to the south, Uzbekistan to the west, Kyrgyzstan to the north, and China to the east....
, Rail transport in Tajikistan
Rail transport in Tajikistan
Rail transport in Tajikistan is limited, as the railroad system totals only of track, all of it broad gauge. The system connects the main urban centers of western Tajikistan with points in neighboring Uzbekistan and Turkmenistan...
Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
, Ukrainian Railways Uzbekistan
Uzbekistan
Uzbekistan , officially the Republic of Uzbekistan is a doubly landlocked country in Central Asia and one of the six independent Turkic states. It shares borders with Kazakhstan to the west and to the north, Kyrgyzstan and Tajikistan to the east, and Afghanistan and Turkmenistan to the south....
, Rail transport in Uzbekistan
Other countries with extensive usage
FinlandFinland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
, Rail transport in Finland
Rail transport in Finland
The Finnish railway network consists of a total of 5,919 km of railways built with Russian gauge track. Passenger trains are operated by the private state-owned VR Group. They serve all the major cities and many rural areas, though railway connections are available to fewer places than bus...
Iraq
Iraq
Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....
, Iraqi Republic Railways
Iraqi Republic Railways
Iraqi Republic Railways Company ' is the national railway operator in Iraq.-Network:...
Turkey
Turkey
Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...
, Rail transport in Turkey
Rail transport in Turkey
Turkey has a well-developed, state-owned railway system built to standard gauge which falls under the remit of the Ministry of Transport and Communication. The primary rail carrier is the Türkiye Cumhuriyeti Devlet Demiryolları which is responsible for all long-distance and cross-border freight...
Gabon
Gabon
Gabon , officially the Gabonese Republic is a state in west central Africa sharing borders with Equatorial Guinea to the northwest, Cameroon to the north, and with the Republic of the Congo curving around the east and south. The Gulf of Guinea, an arm of the Atlantic Ocean is to the west...
, Trans-Gabon Railway
Trans-Gabon Railway
The Trans-Gabon Railway is the only railway in Gabon. It runs 670 km east from Owendo port station in Libreville to Franceville via numerous stations, the main ones being Ndjolé, Lopé, Booué, Lastoursville and Moanda.- Construction :...
(called Willison)
Some usage
SwedenSweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
&
NorwayNorway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
(Malmbanan
Malmbanan
The Iron Ore Line is a long railway line between Riksgränsen and Boden in Norrbotten County, Sweden. The line contains two branches, from Kiruna to Svappavaara and from Gällivare to Koskullskulle. The term is often colloquially used to also include the Ofoten Line, from Riksgränsen to Narvik in...
/Ofotbanen
Ofotbanen
The Ofoten Line is a railway line in Narvik, Norway. It runs from the Port of Narvik to Riksgränsen on the Norway–Sweden border, where the line continues as the Ore Line via Kiruna and Gällivare to Luleå. The Ofoten Line is single track, electrified at and has seven stations. The line only...
); Used exclusively by heavy iron-ore trains. Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
; Miniature SA3 used on some sugarcane tramways and underground colliery railways. Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
(Uzhhorod – Košice broad gauge track); Heavy iron-ore transports from Ukraine
Ukraine
Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...
. Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
(Broad Gauge Metallurgy Line); The longest broad gauge railway line in Poland. It is used only for freight traffic, mainly iron ore and coal.
See also
- C-AKv couplerC-AKvThe C-AKv coupler is a fully automatic center coupler for railway cars, which is designed as a replacement for the European buffers-and-chain coupler. Its profile is based on the Willison profile of the Russian SA3 coupler...
- Coupling (railway) by countryCoupling (railway) by countryCoupling by country generally list the main national system and exclude minor narrow gauge or industrial lines of short length. Modern EMU or DMU passenger vehicles are also excluded...
- Heaviest trainsHeaviest trainsThe heaviest trains in the world are freight trains hauling bulk commodities such as coal and iron ore. One might distinguish between regular operations, and occasional record breaking runs...
of 30000 ST (27,216 t; 26,786 LT) use AAR couplers. - Longest trainsLongest trainsConventional freight trains can average nearly 2,000 metres. Freight trains with a total length of three or four times that average are possible with the advent of DPUs , or additional locomotive engines between or behind long chains of freight cars...
of 2.5 km (1.6 mi) - Unicoupler/Intermat