South African Class 6D 4-6-0

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

Ex CGR Eastern System 6th Class no. 665, SAR Class 6D no. 594, at Sydenham Loco, 29 December 1965
Type and origin
Power type Steam
Designer Cape Government Railways
Builder Neilson, Reid and Company
Serial number 5240-5272 [1]
Model CGR 6th Class
Build date 1898 [1][2]
Total produced 33
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: 42 ft 8.625 in (13.021 m)
Engine:
5 ft 5.5 in (1.664 m) bogie
11 ft 4 in (3.454 m) coupled
20 ft 7.75 in (6.293 m) total
Tender:
10 ft (3.048 m)
Length 51 ft 11.375 in (15.834 m)
Height 12 ft 10 in (3.912 m)
Frame Plate frame
Axle load 12.5 long tons (12.7 t) on 2nd & 3rd drivers
Weight on drivers 36.95 long tons (37.5 t)
Locomotive weight 48.15 long tons (48.9 t)
Tender weight 33,056 lb (15.0 t) empty
33.2 long tons (33.7 t) w/o
Locomotive and tender
combined weight		 99,680 lb (45.2 t) empty
81.35 long tons (82.7 t) w/o
Tender type YC - YB, YC, YE, YE1 permitted
* 3 axle tender
* 37 in (940 mm) wheels
* Length 21 ft 2.875 in (6.474 m)
Fuel type Coal
Fuel capacity 7.5 long tons (7.6 t)
Water capacity 2,600 imp gal (12,000 l)
Boiler 4 ft 4 in (1.321 m) inside diameter
11 ft 2.125 in (3.407 m) inside length
6 ft 8 in (2.032 m) pitch
Boiler pressure 170 psi (1,170 kPa) as built
180 psi (1,240 kPa) reboilered
Firegrate area 18 sq ft (1.672 m2)
Heating surface:
– Tubes		 185 tubes 1.875 in (47.6 mm) diameter
1,015 sq ft (94.297 m2)
– Firebox 107 sq ft (9.941 m2)
– Total 1,122 sq ft (104.237 m2)
Cylinders Two
Cylinder size 17 in (432 mm) bore
26 in (660 mm) stroke
Valve gear Stephenson
Performance figures
Tractive effort At 75% boiler pressure:
17,740 lbf (78.9 kN) at 170 psi (1,170 kPa)
18,780 lbf (83.5 kN) at 180 psi (1,240 kPa) [3]
Career
Operator(s) Cape Government Railways
South African Railways
Sudan Railways
Class CGR 6th Class, SAR Class 6D
Number in class 33
Number(s) CGR 234-259, 585, 586 & 594, 665-668
SAR 565-597 [2][4][5]
Sudan M714-M715
Delivered 1898
First run 1898
Withdrawn 1973 [6]

The South African Class 6D 4-6-0 of 1898 is a South African steam locomotive from the pre-Union era in the Cape Colony.

In 1898 a fourth batch of thirty-three 6th Class 4-6-0 steam locomotives were placed in service by the Cape Government Railways. In 1912, when these locomotives were assimilated into the South African Railways, they were renumbered and reclassified to Class 6D.[2][4][6]

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, at the time Chief Locomotive Superintendent of the CGR, and under the supervision of H.M. Beatty, at the time 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.[2]

The thirty-three locomotives in this fourth group of the 6th Class were built in 1898 by Neilson, Reid and Company. Of these locomotives, twenty-six went to the CGR’s Western System, numbered in the range from 234 to 259, three to the Midland System, numbered 585, 586 and 594, and four to the Eastern System, numbered in the range from 665 to 668.[2]

These locomotives represented a further advance on earlier 6th Class locomotives, with a greater heating surface and a larger grate area. They did, however, revert to the same Type YC six wheeled tenders that were earlier used with the second group of 6th Class locomotives.[2]

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.[4][7]

When these locomotives were assimilated into the SAR in 1912, they were renumbered in the range from 565 to 597 and reclassified to Class 6D. The rest of the CGR’s 6th Class locomotives, together with the Class 6-L1 to 6L3 locomotives inherited by the Central South African Railways (CSAR) from the Oranje-Vrijstaat Gouwerment-Spoorwegen (OVGS) via the Imperial Military Railways (IMR), were grouped into thirteen more sub-classes by the SAR. The 4-6-0 locomotives became SAR Classes 6, 6A to 6C, 6E to 6H and 6J to 6L, the 2-6-2 locomotives became Class 6Y and the 2-6-4 locomotives became Class 6Z.[3][4][5]

Service

South Africa

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.[2]

Sudan

During World War II sixteen locomotives of the Classes 6 to 6D were transferred to the Middle East to assist with the war effort during the North African Campaign. The two Class 6D locomotives in this group were numbers 572 and 587. They were sold to the Sudan Railways Corporation in 1942 and renumbered M714 and M715, in the same order as their former SAR engine numbers.[2][6][8]

Renumbering

The Class 6D works numbers, system allocation and renumberings are shown in the table.[2][4][5]

See also

References

  1. ↑ 1.0 1.1 Neilson, Reid works list, compiled by Austrian locomotive historian Bernhard Schmeiser
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 47, 56–57. ISBN 978-0-7153-5382-0.
  3. ↑ 3.0 3.1 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
  4. ↑ 4.0 4.1 4.2 4.3 4.4 Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 14, 31-32 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
  5. ↑ 5.0 5.1 5.2 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.
  6. ↑ 6.0 6.1 6.2 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 41–44. ISBN 0869772112.
  7. ↑ The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
  8. ↑ Class 6 to 6D sold to Sudan Railways during the WWII North African Campaign, list compiled by Austrian locomotive historian Reimar Holzinger