South African Class 6F 4-6-0

South African Class 6F 4-6-0
ex CGR 6th Class 4-6-0

Ex CGR 6th Class, SAR Class 6F
Type and origin
Power type Steam
Designer Cape Government Railways
Builder Sharp, Stewart and Company
Serial number 4631–4632
Model CGR 6th Class
Build date 1900 [1]
Total produced 2
Specifications
Configuration 4-6-0 "Tenwheeler"
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading wheel
diameter		 28.5 in (724 mm)
Driver diameter 54 in (1,370 mm)
Wheelbase Total: 47 ft 2.5 in (14.389 m)
Engine:
5 ft 6 in (1.676 m) bogie
11 ft 4 in (3.454 m) coupled
20 ft 8 in (6.299 m) total
Tender:
4 ft 7 in (1.397 m) bogie
16 ft 1 in (4.902 m) total
Length 54 ft 6.625 in (16.627 m)
Height 12 ft 10 in (3.912 m)
Frame Bar frame
Axle load 12.35 long tons (12.5 t) on 1st & 3rd drivers
Weight on drivers 37 long tons (37.6 t)
Locomotive weight 47.55 long tons (48.3 t)
Tender weight 36.4 long tons (37.0 t)
Locomotive and tender
combined weight		 83.95 long tons (85.3 t)
Tender type 2 axle bogies
33.5 in (851 mm) wheels
Fuel type Coal
Fuel capacity 6 long tons (6.1 t)
Water capacity 2,780 imp gal (12,600 l)
Boiler 4 ft 7 in (1.397 m) inside diameter
11 ft 2.125 in (3.407 m) inside length
6 ft 9 in (2.057 m) pitch
Boiler pressure 180 psi (1,240 kPa)
Firegrate area 18.75 sq ft (1.742 m2)
Heating surface:
– Tubes		 182 tubes 2 in (50.8 mm) diameter
1,065 sq ft (98.942 m2)
– Firebox 105 sq ft (9.755 m2)
– Total 1,170 sq ft (108.697 m2)
Cylinders Two
Cylinder size 17 in (432 mm) bore
26 in (660 mm) stroke
Valve gear Stephenson
Performance figures
Tractive effort 18,780 lbf (84 kN) at 75% pressure
Career
Operator(s) Cape Government Railways
South African Railways
Class CGR 6th Class, SAR Class 6F
Number in class 2
Number(s) CGR 260-261
SAR 604-605 [1][2][3]
Delivered 1900
First run 1900
Withdrawn 1929 [4]

The South African Class 6F 4-6-0 of 1900 is a South African steam locomotive from the pre-Union era in the Cape Colony.

In 1900 two redesigned 6th Class 4-6-0 steam locomotives were placed in service by the Cape Government Railways. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 6F.[1][2][4]

Manufacturer

The 6th Class 4-6-0 passenger steam locomotive was designed at the Salt River works of the Cape Government Railways (CGR) at the same time as the 7th Class, both according to the specifications of Michael Stephens, then Chief Locomotive Superintendent of the CGR, and under the supervision of H.M. Beatty, then Locomotive Superintendent of the Cape Western System. Whereas the 7th Class was conceived primarily as a goods locomotive, the 6th Class was intended to be its fast passenger service counterpart.[1]

The two 6th Class locomotives that were placed in service by the CGR in 1900 were built by Sharp, Stewart and Company, numbered 260 and 261 and allocated to the Western System. They reflected the decision of H.M. Beatty, who had succeeded Michael Stephens as Chief Locomotive Superintendent in 1895, to adopt bar frames for future CGR locomotives.[1]

They were also equipped with the large commodious cabs which were to become standard in all subsequent designs. They had larger heating surfaces and grate areas than any of the previous 6th Class locomotives, with the boiler pressure increased to 180 pounds per square inch (1,240 kilopascals) and with larger tenders riding on bogies. In visual appearance they differed from all previous 6th Class locomotives by having higher mounted running boards without driving wheel fairings.[1]

Class 6 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.[2][5]

When these two locomotives were assimilated into the SAR in 1912, they were renumbered 604 and 605 and reclassified to Class 6F.[2][3][6]

The rest of the CGR’s 6th Class locomotives, together with 6th Class locomotives that were inherited from the Oranje-Vrijstaat Gouwerment-Spoorwegen (OVGS) via the Imperial Military Railways (IMR) and the Central South African Railways (CSAR), were grouped into thirteen more sub-classes by the SAR. The 4-6-0 locomotives became SAR Classes 6, 6A to 6E, 6G, 6H and 6J to 6L, the 2-6-2 locomotives became Class 6Y and the 2-6-4 locomotives became Class 6Z.[2][3][6]

Service

The Class 6 series of locomotives were introduced primarily as passenger locomotives, but when the class became displaced by larger and more powerful locomotive classes, it literally became a "Jack-of-all-trades" that proved itself as one of the most useful and successful locomotive classes ever to be designed at the Salt River shops. It went on to see service in all parts of the country except Natal and was used on all types of traffic.[1]

These two Class 6F locomotives were placed in service on the Cape mainline. Compared to most of the rest of the Class 6 family, they had a relatively short lifespan of less than thirty years and were withdrawn from service by 1929.[4]

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 47–48, 56. ISBN 978-0-7153-5382-0.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 14, 32 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
  3. ↑ 3.0 3.1 3.2 Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 137–138. ISBN 978-0-7153-5427-8.
  4. ↑ 4.0 4.1 4.2 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. p. 43. ISBN 0869772112.
  5. ↑ The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
  6. ↑ 6.0 6.1 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended