2-6-0+0-6-2

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WheelArrangement 2-6-6-2.svg
Puffing Billy Railway Garratt G42, originally built for the Victorian Government Railways in 1926.

In the Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-6-0+0-6-2 is a Garratt articulated locomotive using a pair of 2-6-0 power units back to back, with the boiler and cab suspended between them. The 2-6-0 arrangement has a single pair of leading wheels in a leading truck, followed by six driving wheels (three pairs) rigidly mounted in the locomotive's frame, with no trailing wheels. Since the 2-6-0 type was often called the Mogul type, the corresponding Garratt type was usually known as a Double Mogul. A Mallet type locomotive with the same wheel arrangement is classified as 2-6-6-2.

Other equivalent classifications are:

Overview[edit]

The 2-6-0+0-6-2 was the second Garratt type to appear after the 0-4-0+0-4-0 and was first used on the fourth through ninth Garratts to be constructed.

Usage[edit]

Australia[edit]

Western Australian Government Railways MSA class Garratt locomotive no MSA468, circa 1930

A group of six locomotives of 3 ft 6 in (1,067 mm) gauge were constructed for the Western Australian Government Railways in 1911 as their Class M.[1] Further locomotives for this railway included seven more Class Ms in 1912.

The Australian Portland Cement Company took delivery of two 3 ft 6 in (1,067 mm) gauge locomotives in 1936 and 1939 as their no. 1 and no. 2 engines for the Quarry line at Fyansford, Victoria. These engines replaced two Vulcan Iron Works 0-6-0 saddle-tanks, numbers 4 and 5, on the mainline haul and were then later displaced by Australian Standard Garratt no. G33.

Fyansford no. 2, by then a combination of no. 2's centre unit and no. 1's engine units, was in service until 1966 when the quarry line was replaced by a conveyor belt. Fyansford no. 2 will be evaluated in 2015 for return to service on the Bellarine Railway, after having been moved there from the Menzies Creek Museum of the Puffing Billy Railway in 2010.

South Africa[edit]

Narrow gauge[edit]

Between 1919 and 1925 the South African Railways (SAR) placed five Class NG G11 Garratt locomotives with a 2-6-0+0-6-2 wheel arrangement in service on the Avontuur 2 ft (610 mm) narrow gauge line through the Langkloof and also in Natal. They were the first Garratt locomotives to enter service in South Africa.[3][4][5]

Three locomotives were ordered from Beyer, Peacock and Company (BP) in 1914, together with an order for a single Cape gauge Class GA Garratt. Production was disrupted by World War I, however, and BP was only able to deliver the locomotives in 1919, after cessation of hostilities. All three, numbered 51 to 53, were erected at Uitenhage and put on trials on the Avontuur line in May 1920. These first three locomotives were not superheated. They had outside plate frames, Walschaerts valve gear, Belpaire fireboxes and used saturated steam and slide valves.[3]

Restored SAR Class NG G11 no. 54 "Solly" at Chelsea, 3 April 1990

Having been proven successful during trials, another two locomotives were ordered from BP. Numbers 54 and 55 were delivered in 1925 and placed in service in Natal. Since these two were superheated, they had longer smokeboxes and were 9.5 inches (241 millimetres) longer in overall length, while the incorporation of piston valves required alteration of the valve gear. The cabs of the second order locomotives were also improved to offer better protection to the crew.[3][4]

The first three locomotives were soon transferred from the Avontuur line to Natal, where all but one remained for the rest of their service lives, until withdrawal by 1962. Number 51 was later returned to the Avontuur line as yard shunter at Humewood Road. The two locomotives of the second order remained in Natal until 1966, when they were both transferred to the Avontuur line where they remained until they were withdrawn from service in October 1974.[3][4]

Cape gauge[edit]

SAR Class GA, circa 1921

In February 1921 the SAR placed a single experimental Class GA Garratt locomotive with a 2-6-0+0-6-2 wheel arrangement in service. It was ordered from BP in 1914, together with the order for the narrow gauge Class NG G11 Garratts, but wartime hostilities also delayed its delivery until 1920. It was the first Cape gauge Garratt to enter service in South Africa.[3][6]

The locomotive was superheated, with a Belpaire firebox, a plate frame and Walschaerts valve gear. It was erected in the Durban shops and placed in trial service on the Natal main line. During the trials it was found that the absence of trailing carrying wheels on the engine units was a disadvantage, since it led to excessive flange wear on the driving wheels. As a result the locomotive remained the only representative of its Class and all subsequent Garratt models of the SAR were equipped with trailing Bissel trucks on their engine units. It was withdrawn from service in 1938 because of a cracked frame and scrapped.[3][4][6][7]

United Kingdom[edit]

2-6-0+0-6-2 'Norfolk Hero'

One twenty-first century example of this wheel arrangement has been built for the Wells and Walsingham Light Railway, a 10 14 in (260 mm) gauge heritage railway in Norfolk, England. An earlier 2-6-0+0-6-2 Garratt, number 3, the 'Norfolk Hero', was built by Neil Simkins in 1986. In 2010 the fleet was augmented by a new Garratt, Number 6, the 'Norfolk Heroine'.

References[edit]

 
Search Wikimedia Commons
  Wikimedia Commons has media related to:
  1. ^ a b Hamilton, Gavin N., The Garratt Locomotive - Garratt Locomotives produced by Beyer, Peacock, retrieved 10 November 2012 
  2. ^ Hamilton, Gavin N., The Garratt Locomotive - Garratt Locomotives from Other Builders, retrieved 10 November 2012 
  3. ^ a b c d e f Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 88–89, 105–106. ISBN 0869772112. 
  4. ^ a b c d Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. pp. 25, 123. ISBN 0715386387. 
  5. ^ Sandstone Steam Railroad
  6. ^ a b Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. p. 41. ISBN 978-0-7153-5427-8. 
  7. ^ Hendrie (10 December 1921). "Engine Power on the S.A.R.". South African Mining and Engineering Journal. XXXII (1576): 529.