Information About4-8-4 |
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| 4-08-4 | |
| 1927 introductions | |
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Under the Whyte Notation for the classification of Steam Locomotives , a 4-8-4 Locomotive has four Leading Wheel s, eight coupled Driving Wheel s and four Trailing Wheel s. The equivalent UIC Classification is 2'D2'. The 4-8-4 was an obvious progression from the 4-8-2 "Mountain" and the 4-6-4 "Hudson" types, combining the 4-8-2's ability to have more weight on the driving wheels (leading to greater traction, and allowing a larger, more powerful locomotive) and the 4-6-4's larger Firebox supported by a 4-wheel trailing truck, allowing for freer steaming, particularly at speed. DEVELOPMENT IN THE UNITED STATES The first 4-8-4 was produced in 1927 by Alco for the Northern Pacific Railway , and the type was therefore named "Northern". Southern railroads in particular did not find this name very suitable, so they chose other names. The 4-8-4 proved to be the best choice of locomotive arrangement for both express passenger and fast freight service. It was not suited to heavy Drag Freight , but faster and lighter trains were well suited to the type. The 4-8-4 was a late development and was often 'name' passenger power at the time of steam's demise, and many were are now preserved in museums, with a few in running condition. Union Pacific Railroad 844 , the last Steam Locomotive built for the UP, has never been retired from service. It is used for charter service and for publicity for the railroad. It is the only steam locomotive never retired by a Class I Railroad . OTHER COUNTRIES France The lone 2006 but no further examples were built as SNCF focussed on electric traction for its future motive power development. 242A1 was scrapped in 1960. Germany The 2006 However due to World War II , no more units were produced and as trains in Germany are less heavy, no real need was seen for such a heavy express train locomotive. Many parts as the boiler were standardised and also used in BR 45 heavy freight train locomotives. Both BR 06 prototypes were scrapped in the 1950s. Australia Three classes of 4-8-4 tender locomotive have been built for use in Australia:
New Zealand The NZR 2006 South Africa In 1953, a time when 4-8-4s on many American railroads were being replaced by diesel-electric locomotives, 2006 A novel feature of many of these locomotives was the use of enormous condensing tenders, designed to save water in arid areas by converting exhaust steam back to water. SAR Class 25 4-8-4 - retrieved 3rd November 2006 In 1981, a Class 25 locomotive was rebuilt into the experimental Class 26NC "Red Devil". This relatively compact locomotive (the engine unit weighed just 123 tonnes) was capable of extraordinary power (in excess of 4,000 2006 However, like the French 242A1 4-8-4 built 35 years earlier, the 26NC remained a one-off. SAR had decided to modernise its fleet with diesel and electric traction rather than invest further development in steam traction. Soviet Union The 4-8-4 arrangement was represented in the Soviet Union by the P36 series locomotive. As the last Russian standard class steam locomotive, they shared some common components and design attributes with the earlier standard designs, the L class 2-10-0 and LV 2-10-2, plus common attributes with the P34 2-6-6-2 Mallet and P38 2-8-8-4 Mallet. They were the only semi-streamlined steam locomotives built in Russia, although a number of fully streamlined locomotives were built. 251 examples were produced from 1954 to 1956. Brazil French-built meter gauge 4-8-4 type designed by Frenchman André Chapelon after the left SNCF (where he had designed the only French 4-8-4). ALCO also built 4-8-4s for Brazil. China China's 4-8-4s were the 'KF' class. Chinese Government Railways Class KF1 designed by Colonel Kenneth Cantlie No 607 is preserved by the National Railway Museum, UK. Bolivia Bolivia had 4-8-4s. PRESERVATION Many 4-8-4 locomotives have been preserved in museums, and a few are in operational condition. Some of the more notable of this type are: operates in excursion service on the BNSF Railway . It is seen here passing through Streator, Illinois , in 1993 .]] H220, the largest non-articulated steam locomotive built in Australia, is believed to be the only surviving three-cylinder 4-8-4.(based on SNCF 242A1 and DR BR 06 locomotives being scrapped) steamtrainartist.com Victorian Railways H Class 4-8-4 - retrieved 1 November 2006 ]]
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