The South African Railways Class GB 2-6-2+2-6-2 of 1921 was an articulated steam locomotive. In June 1921, the South African Railways placed a single experimental Class GB Garratt articulated steam locomotive with a

2-6-2+2-6-2 Under the Whyte notation for the classification of steam locomotives by wheel arrangement, is an articulated locomotive using a pair of power units back to back, with the boiler and cab suspended between them. The 2-6-2 wheel arrangement has ...

Double Prairie type wheel arrangement in service. Six more of these locomotives entered service in 1924.Espitalier, T.J.; Day, W.A.J. (1945). ''The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued).'' South African Railways and Harbours Magazine, November 1945. p. 867.

Manufacturer

The first experimental model of eventually seven Class GB branch line Garratt articulated locomotives was one of altogether five Garratts which were ordered by the South African Railways (SAR) from

Beyer, Peacock and Company Beyer, Peacock and Company was an English railway locomotive manufacturer with a factory in Openshaw, Manchester. Founded by Charles Beyer, Richard Peacock and Henry Robertson, it traded from 1854 until 1966. The company exported locomotives, ...

(BP) in 1914. The rest of the order consisted of three narrow gauge Class NG G11 2-6-0+0-6-2 locomotives and a single experimental Class GA 2-6-0+0-6-2 mainline locomotive. Production was disrupted by the

First World War World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

, however, and BP was only able to deliver the narrow gauge locomotives in 1919 and the two Cape gauge locomotives in 1921, after cessation of hostilities.

Characteristics

The Class GB was numbered 1650, but the engine number was later changed to 2166. The locomotive was erected in the Durban shops and placed in service in June 1921. It was superheated, with a

Belpaire firebox The Belpaire firebox is a type of firebox used on steam locomotives. It was invented by Alfred Belpaire of Belgium in 1864. Today it generally refers to the shape of the outer shell of the firebox which is approximately flat at the top and squa ...

, plate frames and

Walschaerts valve gear The Walschaerts valve gear is a type of valve gear used to regulate the flow of steam to the pistons in steam locomotives, invented by Belgium, Belgian railway mechanical engineering, engineer Egide Walschaerts in 1844. The gear is sometimes name ...

. The boiler was provided with the Gresley type air valve and mechanical lubrication was provided for the coupled wheel axle boxes. In 1924, six more locomotives of this Class were placed in service, also built by BP and numbered in the range from 2160 to 2165. They embodied all the improvements which experience with the first engine had shown desirable. The main differences between these locomotives and the original were revised boiler proportions and a larger water bunker capacity. The most obvious difference was a more completely enclosed cab with side windows instead of the curved cut-outs in the cab sides of the first locomotive. They were also heavier, compared to the of the engine of 1921.

Service

The first locomotive was placed in service working passenger trains on the Natal South Coast line. It proved to be a successful locomotive, having good riding qualities and flexibility on light track with poor ballasting and many curves of radius. A couple of the second batch of locomotives joined the first one on the South Coast line for a brief period, but most went directly to the Eastern Cape where they were used on the

Port Alfred A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Ha ...

branch and the

Aliwal North Aliwal North (officially Maletswai) is a town in central South Africa on the banks of the Orange River, Eastern Cape Province. It is a medium-sized commercial centre in the northernmost part of the Eastern Cape. History Sir Harry Smith, then ...

Barkly East Barkly East is a town in Eastern Cape Province, South Africa, seat of the Joe Gqabi District Municipality, and 117 km by road E.S.E. of Aliwal North, lying in the mountainous area just south of Lesotho. The town lies at the southern tip of t ...

line, famous for its reverses and its 1 in 30 (3⅓%) compensated ruling gradients. The Natal locomotives were soon also relocated to work there when the Class GC Garratts replaced them on the South Coast line later in 1924. They remained working on the Barkly East branch until they were withdrawn from service in 1967.

Illustration

The main picture shows the retired first Class GB, no. 2166, originally no. 1650, at Voorbaai near Mosselbaai on 4 September 1997. Since the top of the front bunker is only about above the railhead, these locomotives were later equipped with a pedestal between the headlight and the water inlet to enable crew members to reach the overhead equipment when taking water. File:SAR Class GB 2160 (2-6-2+2-6-2).jpg, No. 2160, c. 1930, with Johnston link-and-pin couplers and cab side windows File:48 GB 2-6-2+2-6-2 no 2166 at Voorbaai 1997-SEP-04.jpg, No. 2166 with curved cut-out cab sides, Voorbaai, 4 September 1997 File:Garratt GB - Constructed by Davey McFarlane. - 1 1-2 inch scale live steam model.jpg, Garratt GB - Live Steam Model, Built by Davey McFarlane File:Garratt GB - Constructed by Davey McFarlane..jpg, Garratt GB (left hand side) - Modenso - Bloemfontein Society of Model Engineers

References

{{Locomotives of South Africa

2360 In contemporary history, the third millennium of the anno Domini or Common Era in the Gregorian calendar is the current millennium spanning the years 2001 to 3000 ( 21st to 30th centuries). Ongoing futures studies seek to understand what is ...

Beyer, Peacock locomotives 2-6-2+2-6-2 locomotives Garratt locomotives Cape gauge railway locomotives Railway locomotives introduced in 1921 1921 in South Africa