South African Class GCA 2-6-2+2-6-2
| South African Class GCA 2-6-2+2-6-2 | |
|---|---|
|
Class GCA no. 2615 at Greyville, November 1971 | |
| Type and origin | |
| Power type | Steam |
| Designer | Beyer, Peacock and Company |
| Builder | Friedrich Krupp AG |
| Serial number | 970-982, 1042-1068 [1][2] |
| Model | Class GCA |
| Build date | 1927-1928 |
| Total produced | 39 |
| Specifications | |
| Configuration | 2-6-2+2-6-2 "Double Prairie" Garratt |
| Gauge | 3 ft 6 in (1,067 mm) Cape gauge |
| Leading wheel diameter | 28.5 in (724 mm) |
| Driver diameter | 42.75 in (1,090 mm) |
| Trailing wheel diameter | 28.5 in (724 mm) |
| Wheelbase |
Total: 56 ft 8 in (17.272 m) Engines: 8 ft (2.438 m) coupled 17 ft 8.25 in (5.391 m) total |
| Length | 64 ft 9 in (19.736 m) |
| Height | 12 ft 7 in (3.835 m) |
| Frame | Bar frame, 29 ft 8 in (9.042 m) between pivot centres |
| Axle load |
1st order: 11.8 long tons (12.0 t) on 6th driver 2nd order: 11.7 long tons (11.9 t) on 5th driver |
| Weight on drivers |
1st order: 66.15 long tons (67.2 t) 2nd order: 66.85 long tons (67.9 t) |
| Locomotive weight |
1st order: 178,556 lb (81.0 t) empty 104.3 long tons (106.0 t) w/o 2nd order: 181,888 lb (82.5 t) empty 105.8 long tons (107.5 t) w/o |
| Fuel type | Coal |
| Fuel capacity | 7 long tons (7.1 t) |
| Water capacity |
2,000 imp gal (9,100 l) front 1,000 imp gal (4,500 l) rear |
| Boiler |
5 ft 2 in (1.575 m) inside diameter 11 ft 3.625 in (3.445 m) inside length 7 ft 4.375 in (2.245 m) pitch |
| Boiler pressure | 180 psi (1,240 kPa) |
| Firegrate area | 34 sq ft (3.159 m2) |
| Heating surface: – Tubes |
141 tubes 2 in (50.8 mm) diameter 24 tubes 5.5 in (140 mm) diameter 1,225 sq ft (113.806 m2) |
| – Flues | 21 sq ft (1.951 m2) |
| – Firebox | 142 sq ft (13.192 m2) |
| – Total | 1,388 sq ft (128.949 m2) |
| Superheater area | 331 sq ft (30.751 m2) |
| Cylinders | Four |
| Cylinder size |
14 in (356 mm) bore 23 in (584 mm) stroke [3] |
| Valve gear | Walschaerts [4] |
| Performance figures | |
| Tractive effort | 28,470 lbf (127 kN) at 75% pressure |
| Career | |
| Operator(s) | South African Railways |
| Class | Class GCA |
| Number in class | 39 |
| Number(s) | 2190-2202, 2600-2625 |
| Delivered | 1927-1928 |
| First run | 1927 |
| Withdrawn | 1975 |
The South African Class GCA 2-6-2+2-6-2 of 1927 is a South African steam locomotive from the South African Railways era.
In 1927 the South African Railways placed thirteen Class GCA Garratt articulated steam locomotives with a 2-6-2+2-6-2 Double Prairie type wheel arrangement in branchline service. Another twenty-six locomotives were acquired in 1928.[1][3][4]
Manufacturer
The Class GCA 2-6-2+2-6-2 Double Prairie type Garratt locomotive was based on the Class GC and built to the same specifications, with the same tractive effort and main dimensions but with bar frames instead of plate frames. They also differed in general appearance, having round top fireboxes instead of the Belpaire fireboxes of the Class GC and with water tanks and built-up coal bunkers of a different shape. They were ordered from Friedrich Krupp AG of Essen in Germany, who delivered thirteen locomotives in 1927, numbered in the range from 2190 to 2202.[1][3][4][5]
A second order for another twenty-six locomotives was placed with the same manufacturer in 1928. These were numbered in the range from 2600 to 2625 when they were delivered in that same year. The second order locomotives differed slightly from the first order, being slightly heavier. Like the Class GC, they were all superheated and had Walschaerts valve gear.[1][3][4]
Service
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The first order locomotives were placed in service on the Natal South Coast line, while the second order locomotives were distributed wherever their services were required. These could be found working around Pietermaritzburg on the Donnybrook to Underberg and Greytown to Mount Alida branchlines, while some ended up at Nelspruit in the Eastern Transvaal Lowveld for service on the Graskop branchline. They proved to be good locomotives, although some trouble was experienced with coupling rods breaking, attributed to driving them at excessive speed while maintaining schedules with their small driving wheel diameter of only 42.75 inches (1,090 millimetres).[1][4]
By 1973, the thirty-nine original members of the Class had dwindled to seven, all stationed at Mason’s Mill in Pietermaritzburg from where they still worked the light rail Underberg branch, often double-heading. By April of that year, however, the number had dropped to five. They were all withdrawn from service in October 1975. One of their last tasks was to work the track re-railing train that laid the heavier rails which enabled diesel-electric locomotives to finally replace them.[5]
Illustration
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No. 2621 plinthed at Nelspruit, April 1993
See also
- Articulated locomotive numbering and classification
- List of South African locomotive classes
- South African Class GB 2-6-2+2-6-2
- South African Class GC 2-6-2+2-6-2
- South African Class GD 2-6-2+2-6-2
- South African Class GDA 2-6-2+2-6-2
- South African Class GG 2-6-2+2-6-2
- South African Class GK 2-6-2+2-6-2
- South African locomotive history
- The 2-6-2+2-6-2 "Double Prairie"
References
|
- ↑ 1.0 1.1 1.2 1.3 1.4 Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 52–54. ISBN 978-0-7153-5427-8.
- ↑ Hamilton, Gavin N., The Garratt Locomotive - Garratt Locomotives from Other Builders, retrieved 10 November 2012
- ↑ 3.0 3.1 3.2 3.3 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
- ↑ 4.0 4.1 4.2 4.3 4.4 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. p. 90. ISBN 0869772112.
- ↑ 5.0 5.1 Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. p. 110. ISBN 0715386387.
