South African Class 7C 4-8-0
| South African Class 7C 4-8-0 & South African Class 7CS 4-8-0 ex CGR 7th Class 4-8-0 | |
|---|---|
|
Ex CGR (Eastern System) 7th Class no. 765 SAR Class 7C no. 1065 | |
| Type and origin | |
| Power type | Steam |
| Designer | Cape Government Railways |
| Builder | Neilson, Reid and Company |
| Serial number | 6079-6088 [1][2] |
| Model | CGR 7th Class |
| Build date | 1901 [2] |
| Total produced | 10 |
| Specifications | |
| Configuration | 4-8-0 "Mastodon" |
| 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) |
| Wheelbase |
Total: 46 ft 2 in (14.072 m) Engine: 5 ft 3 in (1.600 m) bogie 12 ft (3.658 m) coupled 21 ft 3.5 in (6.490 m) total Tender: 4 ft 7 in (1.397 m) bogie 16 ft 1 in (4.902 m) total |
| Length | 53 ft 4.5 in (16.269 m) |
| Height | 12 ft 10 in (3.912 m) |
| Frame | Plate frame |
| Axle load | 9.7 long tons (9.9 t) on 2nd driver |
| Weight on drivers | 36 long tons (36.6 t) |
| Locomotive weight | 49.1 long tons (49.9 t) |
| Tender weight | 34.1 long tons (34.6 t) |
| Locomotive and tender combined weight | 83.2 long tons (84.5 t) |
| Tender type |
ZE - ZA, ZB, ZC, ZE permitted * 2 axle bogies * 34 in (864 mm) wheels * Length 23 ft 8.5 in (7.226 m) |
| Fuel type | Coal |
| Fuel capacity | 8 long tons (8.1 t) |
| Water capacity | 2,850 imp gal (13,000 l) |
| Boiler |
4 ft 6 in (1.372 m) inside diameter 10 ft 9 in (3.277 m) inside length 6 ft 10 in (2.083 m) pitch |
| Boiler pressure | 180 psi (1,240 kPa) |
| Firegrate area | 18 sq ft (1.672 m2) |
| Heating surface: – Tubes |
As built: 185 tubes 1.875 in (47.6 mm) dia 976 sq ft (90.673 m2) Superheated: 100 tubes 1.875 in (47.6 mm) dia 18 tubes 5.5 in (140 mm) dia 806 sq ft (74.880 m2) |
| – Firebox | 113 sq ft (10.498 m2) |
| – Total |
1,089 sq ft (101.171 m2) as built 919 sq ft (85.378 m2) superheated |
| Superheater type | Not equipped as built |
| Superheater area | 206 sq ft (19.138 m2) |
| Cylinders | Two |
| Cylinder size |
17.5 in (444 mm) bore 23 in (584 mm) stroke |
| Valve gear | Stephenson |
| Performance figures | |
| Tractive effort | 22,240 lbf (98.9 kN) at 75% pressure |
| Factor of adhesion | 3.83 [3] |
| Career | |
| Operator(s) |
Cape Government Railways South African Railways |
| Class |
CGR 7th Class SAR Class 7C, Class 7CS [4] |
| Number in class | 10 |
| Number(s) |
CGR 759-768 SAR 1059-1068 [1][5] |
| Delivered | 1902 |
| First run | 1902 |
| Withdrawn | 1972 [6] |
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The South African Class 7C 4-8-0 of 1902 is a South African steam locomotive from the pre-Union era in the Cape Colony.
In 1902 the Cape Government Railways placed its last ten 7th Class 4-8-0 Mastodon type steam locomotives in service on the Cape Eastern System. In 1912, when all these locomotives were assimilated into the South African Railways, they were renumbered and reclassified to Class 7C.[1][5][6]
Manufacturer
The last of the 7th Class locomotives to be ordered by the Cape Government Railways (CGR) were ten for the Cape Eastern System. They were built by Neilson, Reid and Company in 1901, and delivered and placed in service in 1902 with engine numbers in the range from 759 to 768.[1]
These locomotives differed from all previous 7th Class models in having a large commodious cab with double windows on each side, similar to those that were fitted to the ex Central South African Railways (CSAR) Class 7B locomotives. This afforded greater protection for the crew. They were more than 4 long tons (4.1 tonnes) heavier than the original 7th Class locomotives and they also had larger diameter boilers with a higher boiler pressure, while their power was further improved by their increased cylinder diameter.[1][6]
Class 7 sub-classes
The Union of South Africa was established on 31 May 1910, in terms of the South Africa Act. One of the clauses in the Act required that the three Colonial Government railways, the CGR, the Natal Government Railways and the Central South African Railways, also be united under one single administration to control and administer the railways, ports and harbours of the Union. While the South African Railways (SAR) came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways required careful planning and was only implemented with effect from 1 January 1912.[5][7]
When these locomotives were assimilated into the SAR in 1912, they were renumbered in the range from 1059 to 1068 and reclassified to Class 7C.[1][8][5]
Other Class 7 locomotives that came onto the SAR roster from the CGR and other Colonial railways in the region, namely the CSAR, the Natal Government Railways (NGR), some from the Rhodesia Railways (RR) and, in 1925, from the New Cape Central Railways (NCCR), were grouped into six different sub-classes by the SAR, becoming SAR Classes 7, 7A, 7B and 7D to 7F.[4]
Modifications
During the 1930s many of the Class 7 series locomotives were equipped with superheated boilers and piston valves. On the Classes 7B and 7C this conversion was sometimes indicated with an "S" suffix to the class number on the locomotive number plates, but on the rest of the Class 7 family this distinction was not applied consistently. The superheated versions could be identified by the position of the chimney on the smokebox, with the chimney displaced forward to provide space behind it in the smokebox for the superheater header.[4][6]
Service
In SAR service, the Class 7 series worked on every system in the country. During the South West African Campaign in World War I twenty-nine Class 7 series locomotives were sent to South West Africa (SWA) to assist the expeditionary forces. Three of these were Class 7C locomotives, numbers 1065 to 1067.[3][6]
They proved so successful in that territory that more were gradually transferred there in later years. By the time the Class 24 arrived in SWA in 1949, there were still fifty-three Class 7 series locomotives in use there. Most remained there and were only transferred back to South Africa when the Class 32-000 diesel-electric locomotives replaced them in 1961. In South Africa they remained in branchline service, particularly at Tarkastad and Ladysmith and also on the line from Touws River to Ladismith, until they were finally withdrawn in 1972.[6]
See also
- South African Class 7 4-8-0
- South African Class 7A 4-8-0
- South African Class 7B 4-8-0
- South African Class 7D 4-8-0
- South African Class 7E 4-8-0
- South African Class 7F 4-8-0
- The 4-8-0 "Mastodon"
- Tender locomotive numbering and classification
- South African locomotive history
- List of South African locomotive classes
References
|
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 43–44. ISBN 978-0-7153-5382-0.
- ↑ 2.0 2.1 Neilson, Reid works list, compiled by Austrian locomotive historian Bernhard Schmeiser
- ↑ 3.0 3.1 Pattison, R.G. (1997). The Cape Seventh Class Locomotives (1st ed.). Kenilworth, Cape Town: The Railway History Group. pp. 10, 23, 29–32. ISBN 0958400946.
- ↑ 4.0 4.1 4.2 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
- ↑ 5.0 5.1 5.2 5.3 Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 15, 39 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 46–48. ISBN 0869772112.
- ↑ The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
- ↑ Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. p. 139. ISBN 978-0-7153-5427-8.
