Co-Cos are most suited to freight work as the extra wheels give them good traction. They are also popular because the greater number of axles results in a lower axle load to the track.[1]
HistoryEdit
LMS 10000 of 1947
The first mainline diesel-electric locomotives were of Bo-Bo arrangement. As they grew in power and weight, from 1937 the EMD E-units used an A1A-A1A layout with six axles to reduce axle load, but only four of them were powered. After WWII, the British LMS ordered two prototype locomotives with some of the first Co-Co arrangements.
DRG E 93 class 3,355 hp heavy-freight electric loco of 1933
There were initially few electric locomotives with this wheel arrangement, as they are usually lighter than diesel-electrics of similar power and so could manage a similar axle loading with a simpler Bo-Bo arrangement. Some of the few early examples were the French CC 7100 of 1949 and the British Railways EM2 of 1953.
As high-speed electric locomotives in the 1980s began to achieve powers in the 6,000 hp range, new Co-Co designs appeared, as more axles were needed to distribute this high power. The BR class 92 was a predominantly freight locomotive of this arrangement for the Channel Tunnel, although the passenger Eurotunnel Class 9 instead use a Bo-Bo-Bo arrangement. This provides the same number of axles for traction, although with shorter bogie wheelbases and so gives a smoother ride.
In C-C (Commonwealth) or C′C′ (UIC) arrangements, the axles of each bogie are coupled together. This may be for either a diesel-hydraulic transmission with a mechanical drive shaft to the bogie and final drives to each axle. Otherwise a monomotor bogie with a single traction motor. These are used for both electrics and diesel-electrics.
Co+CoEdit
South African class 3E of 1947, showing the Co+Co arrangement of the bogies with the drawgear below the body frame
Co+Co is the code for a similar wheel arrangement but with an articulated connection between the bogies. The buffer and drawbar forces are taken between the bogies rather than through the frame. These were mostly popular in South Africa.
The 1Co-Co1 wheel arrangement is an alternative to the Co-Co arrangement which has been used where it was desired to reduce axle load. Each 'Co' bogie has an additional non-powered axle in an integral pony truck to spread the load. As the pony truck is articulated within the bogie,[3] the arrangement is (1′Co)(Co1′) in UIC notation.
This rare arrangement was used primarily in Britain with the development of the Bollen bogie; on the Southern Railways' first three prototype mainline diesel-electric designs, 10201–10203,[4] and then on production vehicles in British Rail's Class 40 and "Peaks" (BR classes 44, 45, and 46).[3][5]
1Co+Co1, like Co+Co, is an articulated variant where the drawbar forces are taken between the bogies rather than through the frame. These were used in South Africa, for lighter loadings on the lightly laid 3 ft 6 in (1,067 mm) Cape gauge. A number of Japanese electrics from the 1930s, also on Cape gauge, such as the EF10 also used this arrangement.
The New Zealand DF class were built in the mid-1950s by English Electric in Britain, as the first diesels for the 3 ft 6 in (1,067 mm) New Zealand railways. They were derived from the earlier English Electric 1Co-Co1 bogie design, but to provide increased flexibility for the long wheelbase bogie they used a four-wheeled bogie with more side play, rather than a pony truck.
^ abWebb, Brian (1978). "Class 44". Sulzer Diesel Locomotives of British Rail. David & Charles. p. 30. ISBN0715375148.
^Clough, David N. (2005). "Pre-Nationalisation Prototypes: Southern Railway prototypes Nos 10201–3". Diesel Pioneers. Ian Allan. p. 11. ISBN978-0-7110-3067-1.
^Clough, David N. (2009). "Class 40". British Rail Standard Diesels of the 1960s. Ian Allan. pp. 94–100. ISBN978-0-7110-3373-3.
October 15, 2023
locomotive, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, scholar, jstor, february, 2018,. This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Co Co locomotive news newspapers books scholar JSTOR February 2018 Learn how and when to remove this template message Co Co is the wheel arrangement for diesel and electric locomotives with two six wheeled bogies with all axles powered with a separate traction motor per axle The equivalent UIC classification Europe for this arrangement is Co Co or C C for AAR North America A New Zealand DFT class Co Co diesel electric locomotiveCo Co wheel arrangement Contents 1 Use 2 History 3 Variants 3 1 Electric locomotives 3 2 C C 3 3 Co Co 3 4 1Co Co1 3 5 1Co Co1 3 6 2Co Co2 4 See also 5 ReferencesUse EditCo Cos are most suited to freight work as the extra wheels give them good traction They are also popular because the greater number of axles results in a lower axle load to the track 1 History Edit nbsp LMS 10000 of 1947The first mainline diesel electric locomotives were of Bo Bo arrangement As they grew in power and weight from 1937 the EMD E units used an A1A A1A layout with six axles to reduce axle load but only four of them were powered After WWII the British LMS ordered two prototype locomotives with some of the first Co Co arrangements nbsp The 1903 Hornsby locomotiveThe first C C design recorded was a narrow gauge Hornsby opposed piston Hornsby Akroyd engined locomotive of 1903 for the Chattenden and Upnor Railway There was a two speed mechanical transmission with drive shafts to the bogies and the axles on each bogie were linked by coupling rods 2 Variants EditElectric locomotives Edit nbsp DRG E 93 class 3 355 hp heavy freight electric loco of 1933There were initially few electric locomotives with this wheel arrangement as they are usually lighter than diesel electrics of similar power and so could manage a similar axle loading with a simpler Bo Bo arrangement Some of the few early examples were the French CC 7100 of 1949 and the British Railways EM2 of 1953 nbsp British Rail Class 89 25 kV electricAs high speed electric locomotives in the 1980s began to achieve powers in the 6 000 hp range new Co Co designs appeared as more axles were needed to distribute this high power The BR class 92 was a predominantly freight locomotive of this arrangement for the Channel Tunnel although the passenger Eurotunnel Class 9 instead use a Bo Bo Bo arrangement This provides the same number of axles for traction although with shorter bogie wheelbases and so gives a smoother ride C C Edit nbsp British Railways class 52 WesternIn C C Commonwealth or C C UIC arrangements the axles of each bogie are coupled together This may be for either a diesel hydraulic transmission with a mechanical drive shaft to the bogie and final drives to each axle Otherwise a monomotor bogie with a single traction motor These are used for both electrics and diesel electrics Co Co Edit nbsp South African class 3E of 1947 showing the Co Co arrangement of the bogies with the drawgear below the body frameCo Co is the code for a similar wheel arrangement but with an articulated connection between the bogies The buffer and drawbar forces are taken between the bogies rather than through the frame These were mostly popular in South Africa 1Co Co1 Edit nbsp British Rail Class 40 1Co Co1The 1Co Co1 wheel arrangement is an alternative to the Co Co arrangement which has been used where it was desired to reduce axle load Each Co bogie has an additional non powered axle in an integral pony truck to spread the load As the pony truck is articulated within the bogie 3 the arrangement is 1 Co Co1 in UIC notation This rare arrangement was used primarily in Britain with the development of the Bollen bogie on the Southern Railways first three prototype mainline diesel electric designs 10201 10203 4 and then on production vehicles in British Rail s Class 40 and Peaks BR classes 44 45 and 46 3 5 1Co Co1 Edit Further information 1Co Co1 nbsp Japanese EF10 in 19381Co Co1 like Co Co is an articulated variant where the drawbar forces are taken between the bogies rather than through the frame These were used in South Africa for lighter loadings on the lightly laid 3 ft 6 in 1 067 mm Cape gauge A number of Japanese electrics from the 1930s also on Cape gauge such as the EF10 also used this arrangement 2Co Co2 Edit nbsp New Zealand DF classThe New Zealand DF class were built in the mid 1950s by English Electric in Britain as the first diesels for the 3 ft 6 in 1 067 mm New Zealand railways They were derived from the earlier English Electric 1Co Co1 bogie design but to provide increased flexibility for the long wheelbase bogie they used a four wheeled bogie with more side play rather than a pony truck See also EditCo Bo which has two uncoupled bogiesReferences Edit nbsp Wikimedia Commons has media related to Co Co locomotives Lee Robert 2007 The Railways of Victoria 1854 2004 Melbourne University Publishing p 212 ISBN 978 0 522 85134 2 Webb Brian 1973 The British Internal Combustion Locomotive 1894 1940 David amp Charles p 19 ISBN 0715361155 a b Webb Brian 1978 Class 44 Sulzer Diesel Locomotives of British Rail David amp Charles p 30 ISBN 0715375148 Clough David N 2005 Pre Nationalisation Prototypes Southern Railway prototypes Nos 10201 3 Diesel Pioneers Ian Allan p 11 ISBN 978 0 7110 3067 1 Clough David N 2009 Class 40 British Rail Standard Diesels of the 1960s Ian Allan pp 94 100 ISBN 978 0 7110 3373 3 Retrieved from https en wikipedia org w index php title Co Co locomotive amp oldid 1177691554, wikipedia, wiki, book, books, library,
