Under the Whyte notation for the classification of steam locomotives, 2-6-2 represents the wheel arrangement of two leading wheels, six coupled driving wheels and two trailing wheels.
Other equivalent classifications are: UIC classification
(also known as German classification and Italian classification): 1C1, French classification: 131, Turkish classification: 35, Swiss classification: 3/5.
The majority of American 2-6-2s were tender locomotives but, in Europe, tank locomotives (classified 2-6-2T) were more common.
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The first 2-6-2 or Prairie type locomotives in New Zealand were a fleet of 5 tank engines, built by Manning Wardle of Leeds, England; supplied in 1884-85. The private Wellington and Manawatu Railway used them for construction, maintenance and local service work, and three were taken over as the Wh class in 1908.
The second batch was built to an order for New Zealand Railways Department, with the initial order for 10 being let to Nasmyth, Wilson and Company of Manchester, England. This was the V class, which due to their being overweight and political interference did not go into traffic until 1890.
New Zealand's third batch of Prairie locomotives was ordered by the private Wellington and Manawatu Railway in 1884. Their design was almost identical to the NZR V class, though they were slightly heavier. They could burn any light fuel, coal or wood if available. They were built as designed and entered service in 1886 soon after the WMR started operating. In 1908, with the purchase of the company by the NZR, they also gained the V classification.
Baldwin Locomotive Works built New Zealand's fourth batch of Prairie locomotives, in 1885. These were an almost identical design, altered to utilise off-the-shelf components supplied by Baldwins. This was the New Zealand Railways N class, of which 6 were built in 1885. In 1891, two were built for the Wellington and Manawatu Railway to the same design, and in 1901, four more were built for the NZR. These last four were fitted with Piston Valves actuated by Walschaerts valve gear. By 1908, all of these engines were classified as N class, with the purchase of the WMR by NZR. Between 1894 and 1904, four similar engines were built by Baldwins for the WMR. In 1908, these became Na class and Nc class, with two units each.
The NZR Addington Workshops joined the list of Prairie suppliers in 1889, producing the first of two W class tank engines. These were followed between 1892 and 1901 with 11 similar Wa class tank engines.
Baldwins followed this up with 10 similar Wb class Prairie tank engines in 1898.
In 1930-31, New Zealand dusted off its Prairie plans, after nearly 30 years of Pacific and Baltic locomotive production, with the release into service of 24 C class locomotives designed primarily for shunting and branch line work.
The first 2-6-2 tender locomotives built for a North American customer were built by Brooks in 1900 for the Chicago, Burlington and Quincy Railroad for use on the Midwestern prairies. The type was thus nicknamed the Prairie in North American practice; this name was often used in British practice as well. The 2 foot gauge Sandy River and Rangeley Lakes Railroad in Franklin County, Maine, was a major narrow gauge user.
In the USA the type evolved from the 2-6-0 configuration. The ATSF became one of the largest fleet users of the type and initially had tandem compound cylinders. However, tandem compounds and fast running are by definition incompatible. In 1902 the ATSF had a 2-6-2 with a boiler pressure of a huge (for those days) 220 p.s.i mounted on a large 41 square feet (3.8 m2) fire grate.(Swengel, p. 78.)
Tha major problem with the 2-6-2 as with the 2-10-2 is that these engines have a symmetrical layout, wherein the 'centre of gravity' is almost over the center driving wheel. The reciprocation rods, when working near the center of gravity, induce severe 'side to side' nosing, which if can't be restrained either by a long wheelbase or by the leading and trailing trucks results in 'severe instability'. Though some engines had the connecting rod aligned onto the third driver (like the Chicago and Great Western of 1903) most examples were powered via the second driver, hence the nosing problems remained with the type.(Swengel, p. 79.) In the USA, over 1,000 examples existed of which 100 were high wheeled engines; larger than 69 inches (1.8 m). The Lake Shore & Michigan Southern operated 80-inch (2.0 m) drivers but this did not overcome their inherent instability. The class was not suited to passenger workings because of the nosing problems. (Swengel, p. 80.)
In Australia, no tender versions of the 2-6-2 operated on any system. However, three classes of 2-6-2T did. In New South Wales a class of 20 engines (Class 26) entered service in 1892 and operated until the end of steam. Two are preserved, 2606 at the Rail Transport Museum at Thirlmere and 2605 at the State Mine Museum in Lithgow. The Silverton Tramway operated two 2-6-2T from 1891 and both are preserved in South Australia.
The main 2-6-2T which were built for the Victoria's narrow gauge system are the now famous "Puffing Billy" engines. Two of little locomotives arrived in 1898 from Baldwin Locomotive works and a total of 17 saw service throughout the state on the various narrow gauge timber and gold lines, including Wangaratta and Walhalla. When the VR determined to close the Upper Ferntree Gully to Gembrook narrow gauge route in the mid-1950s the Victorian community refused to let the train die. Today, the Puffing Billy Railway has on active steam roster, a fleet of saved and modified 2-6-2T engines and is one of Victoria's main tourist attractions.
The most numerous steam locomotive type used in Hungary was the 324 class 2-6-2, built from 1909 onwards and which were still at work in the last days of steam. Hungarian State Railways (MAV) also ran three important classes of 2-6-2 tank engines: these were the large 342 class built from 1917, and the smaller 375s and 376s.
H. Cegielski Metal Works in Poznań produced 122 OKl27 class tank locomotives during the period of 1928 - 1933.
In 1951-54 Fablok built a series of 116 Ol49 class tender locomotives for PKP.
Romania designed the 131.000 Class in order to replace the older Hungarian MAV locomotives used on CFR secondary lines. A total of 67 locomotives were built at Reşiţa Works.[1]
Builder details:
In Russia the 2-6-2 was the standard passenger locomotive. They were represented by the pre revolutionary design, the S(С) (Sormovskij) and the Su (Су) series locomotives which appeared in 1928. The pre-revolutionary S-series locomotive has the characteristic pointed nose, absent on the Su locomotive. The suffix 'u' means 'usilenny' which translates as strengthened or uprated. Several are preserved- several Su-series locomotives are even preserved in working order! However, only one pre-revolutionary S-series locomotive is still around - S68. It is located in the Saint Petersburg railway museum.
The Su was the main standard passenger engine on most routes and it was only on the key trunk lines that the IS class 2-8-4 or later the P36 4-8-4 would be used. Therefore the majority of passenger miles were hauled by an Su (Су). Visually the Su was the last true ‘Russian’ looking design before the American influence of high running boards, bar frames and ‘boxpok’ wheels became the norm. The Su retains such features as a clerestory sky light in the cab roof and handrails on the outside of the running board. The handrails were a result of the harsh Russian winters. Ice would build up on running boards making them highly dangerous, enginemen had fallen to their death from moving trains and the fitting of ‘promenade deck’ style handrails was a safety measure ordered by the Tsar (pre revolutionary times). These features, combined with the high (17 ft) loading gauge combine to give the uniquely Russian look. (Russian Steam Locomotives, LeFleming/Price)(Locomotives of Russia 1845 - 1955, V.A.Rakov).
The first UK 2-6-2 tender locomotive was the unsuccessful prototype Midland Railway Paget locomotive of 1908.[2] Thereafter the wheel arrangement was rare on tender locomotives apart from two classes on the London and North Eastern Railway: the V2 and V4 mixed traffic classes, which between them totalled 186 locomotives.
In contrast, 2-6-2 tank locomotives were very widely used on suburban passenger services, particularly by the Great Western Railway which built four main classes between 1903 and 1947 (see GWR 2-6-2T). Sir Henry Fowler of the London Midland and Scottish Railway introduced a successful 2-6-2T class in 1930, which became the basis of further similar classes by Stanier (1935) and Ivatt 1946. Sir Nigel Gresley of the London and North Eastern Railway introduced his V1 and V3 classes in 1930.
The last 2-6-2T locomotives in Britain were the British Railways standard class 2 built between 1953 and 1957. The design derived from the earlier LMS Ivatt Class 2 2-6-2T.
The 2-6-2T layout was popular for large narrow gauge engines but the design was modified to allow the use of a firebox much wider than the track gauge. A standard gauge 2-6-2T normally has inside frames and the firebox is placed between the second and third coupled axles. A narrow gauge one has outside frames and the firebox is placed behind the third coupled axle and clear of the wheels. To minimise the rear overhang, the fuel is carried in side-bunkers (alongside the firebox) instead of a rear bunker. Preserved examples include the Welsh Highland Railway's Russell, the Vale of Rheidol Railway locomotives, numbers 4 and 5 of the Jokioinen Museum Railway, and the Victorian Railways class NA 2-6-2 tank locomotives on the Puffing Billy Railway.
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