South African Class 10 4-6-2
|South African Class 10 4-6-2
ex CSAR Class 10 4-6-2
SAR no. 738 (ex CSAR no. 656) at Sydenham Loco depot, 4 September 1966
|Type and origin|
|Designer||Central South African Railways|
|Builder||North British Locomotive Company|
|Serial number||16194-16203, 16226-16230 |
|Model||CSAR Class 10|
|Gauge||3 ft 6 in (1,067 mm) Cape gauge|
|28.5 in (724 mm)|
|Driver diameter||62 in (1,570 mm) as built
63 in (1,600 mm) no. 745
|33 in (838 mm)|
|Wheelbase||Total: 56 ft 4 in (17.170 m)
6 ft (1.829 m) bogie
10 ft 10 in (3.302 m) coupled
30 ft 2 in (9.195 m) total
4 ft 7 in (1.397 m) bogie
16 ft 9 in (5.105 m) total
|Length||64 ft 6.75 in (19.679 m)|
|Height||12 ft 10 in (3.912 m) as built
12 ft 11 in (3.937 m) no. 745
|Axle load||15.5 long tons (15.7 t) on 2nd & 3rd drivers|
|Weight on drivers||46 long tons (46.7 t)|
|Locomotive weight||72.75 long tons (73.9 t)|
|Tender weight||48,144 lb (21.8 t) empty
49.35 long tons (50.1 t) w/o
|Locomotive and tender
|122.1 long tons (124.1 t)|
|Tender type||XM2 - XC, XC1, XD, XE, XE1, XF, XF1, XF2, XJ, XM, XM1, XM2, XM3, XM4, XP1, XS permitted, MP1 on no. 746 only
* 2 axle bogies
* 34 in (864 mm) wheels
* Length 25 ft 11.625 in (7.915 m)
|Fuel capacity||10 long tons (10.2 t)|
|Water capacity||4,000 imp gal (18,000 l)|
|Boiler||4 ft 6.75 in (1.391 m) inside diameter
18 ft 6.5 in (5.652 m) inside length
7 ft 4 in (2.235 m) pitch
|Boiler pressure||190 psi (1,310 kPa)|
|Firegrate area||35 sq ft (3.252 m2)|
|92 tubes 2.25 in (57.1 mm) diameter
18 tubes 5.25 in (133 mm) diameter
1,463 sq ft (135.917 m2)
|– Firebox||125 sq ft (11.613 m2)|
|– Total||1,588 sq ft (147.530 m2)|
|Superheater area||384 sq ft (35.675 m2)|
|Cylinder size||19.5 in (495 mm) bore
28 in (711 mm) stroke
|Tractive effort||24,470 lbf (109 kN) at 75% pressure|
|Operator(s)||Central South African Railways
South African Railways
|Class||CSAR & SAR Class 10 |
|Number in class||15|
|Number(s)||CSAR 650-664, SAR 732-746 |
In 1904 the Central South African Railways placed fifteen Class 10 steam locomotives with a 4-6-2 Pacific type wheel arrangement in service. In 1912, when they were assimilated into the South African Railways, they were renumbered but retained their Class 10 classification.
Fifteen 4-6-2 Pacific type passenger locomotives, designed by Central South African Railways (CSAR) Chief Locomotive Superintendent P.A. Hyde, were ordered from the North British Locomotive Company (NBL) and delivered in 1904, numbered in the range from 650 to 664. They had plate frames, wide Belpaire fireboxes, outside admission piston valves and Walschaerts valve gear, and were superheated. They were classified as Class 10 by the CSAR.
At the time, the Class 10 was of an extremely advanced design. At 7 feet 4 inches (2.235 metres) above rail level, its boiler centre line was higher than that of any other locomotive in service in South Africa at the time.
They were to form the basis for further development of the Pacific type that was to become the standard express passenger steam locomotive type in South Africa. They were handsome locomotives and their appearance was enhanced by the use of planished steel plates to cover the boiler and cylinder lagging, and they were equipped with two whistles of different tones and a steam turbine generator to power the "Edwards" headlight.
South African Railways
The Union of South Africa was established on 31 May 1910, in terms of the South Africa Act, enacted by the Parliament of the United Kingdom. One of the clauses in the Act required that the three Colonial Government railways, the Cape Government Railways, the Natal Government Railways and the CSAR, 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.
Two of the locomotives were later modified by the SAR. Number 745 was equipped with 1 inch (25.4 millimetres) larger diameter tyres on its coupled wheels, while number 746 was altered to suit a Type MP1 tender as well as the other listed permissible tender types. While the Type MP1 tender had the same coal capacity as the Type XM2 that the locomotives were delivered with, it had a 250 imperial gallons (1,100 litres) larger water capacity.
The Class 10 was designed for use on the newly laid 80 pounds per yard (40 kilograms per metre) track of the CSAR, and it was placed in service hauling the fast passenger trains out of Johannesburg to Volksrust on the Natal line and to Klerksdorp on the Cape line. In later years some were relocated to work in the Noupoort area, while the rest were relegated to suburban work on the lines from Germiston to Kliprivier and the Springs-Nigel-Heidelberg branch, or for pick-up work on the Braamfontein-Klerksdorp line.
The main picture and the following show both sides of the Class 10 locomotive.
- List of South African locomotive classes
- South African Class 10A 4-6-2
- South African Class 10B 4-6-2
- South African Class 10C 4-6-2
- South African Class 10D 4-6-2
- South African locomotive history
- Tender locomotive numbering and classification
- The 4-6-2 "Pacific"
- North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
- North British Locomotive Co. (from J. Lambert)
- South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, p12, as amended
- Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 9, 12, 14, 34 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
- Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 51–52. ISBN 0869772112.
- Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. p. 8. ISBN 0715386387.
- Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 129–130. ISBN 978-0-7153-5382-0.
- The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.