South African Class 6G 4-6-0 Explained

CGR 6th Class 4-6-0 1901 Schenectady
South African Class 6G 4-6-0
Powertype:Steam
Designer:Cape Government Railways
Schenectady Locomotive Works
Builder:Schenectady Locomotive Works
Serialnumber:5646-5653
Buildmodel:CGR 6th Class
Builddate:1901
Totalproduction:8
Whytetype:4-6-0 (Tenwheeler)
Uicclass:2'Cn2
Driver:2nd coupled axle
Leadingdiameter:NaN0NaN0
Coupleddiameter:540NaN0
Tenderdiameter:NaN0NaN0 as built
340NaN0 retyred
Wheelbase:44feet
Engine Total:21feet
Leading:60NaN0
Coupled:11feet
Tender Total:14feet
Tenderbogie:50NaN0
Wheelspacing:1-2: 4feet
2-3: 6feet
Over Couplers:51feet
Height:12feet
Frametype:Bar
Axleload:12lt
Leadingbogie/Pony:12sigfig=4NaNsigfig=4
Coupled 1:11lt
Coupled 2:12lt
Coupled 3:12lt
Tenderbogieload:Bogie 1: 15lt
Bogie 2: 17lt
Tenderaxle:8lt
Weightondrivers:36lt
Locoweight:48lt
Tenderweight:33lt
Locotenderweight:81lt
Tendertype:WE (2-axle bogies)
WE, WG permitted
Fueltype:Coal
Fuelcap:51NaN1
Watercap:2800sigfig=3NaNsigfig=3
Fireboxtype:Round-top
Firearea:18.6square feet
Pitch:6feet
Diameterinside:4feet
Lengthinside:11feet
Smalltubediameter:195: 20NaN0
Boilerpressure:180psi
Safetyvalvetype:Ramsbottom 30NaN0
Totalsurface:1266.5square feet
Tubearea:1155square feet
Fireboxarea:111.5square feet
Cylindercount:Two
Cylindersize:NaN0NaN0 bore
260NaN0 stroke
Valvegear:Stephenson
Valvetype:Richardson balanced slide
Valvetravel:50NaN0
Valvelap:10NaN0
Locobrakes:Steam
Trainbrakes:Vacuum
Coupling:Johnston link-and-pin
AAR knuckle (1930s)
Tractiveeffort:19910lbf @ 75%
Operator:Cape Government Railways
South African Railways
Operatorclass:CGR 6th Class, SAR Class 6G
Numinclass:8
Fleetnumbers:CGR 262-269
SAR 606-613
Deliverydate:1901
Firstrundate:1901
Withdrawndate:1961
Notes:The 2nd coupled axle had flangeless wheels

The South African Railways Class 6G of 1901 was a steam locomotive from the pre-Union era in the Cape of Good Hope.

In 1901, eight redesigned 6th Class 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 designated .[1]

Manufacturer

The original Cape 6th Class locomotive was designed at the Salt River works of the Cape Government Railways (CGR) in 1893, at the same time as the 7th Class.

Three new versions of the 6th Class locomotive entered service on the CGR in 1901, two American-built and one British-built. Of the two American-built versions, one was designed and built by the Schenectady Locomotive Works to the specifications of the CGR locomotive department. They were consequently somewhat different in appearance from the earlier Cape 6th Class locomotives. Eight locomotives were built and delivered, numbered in the range from 262 to 269 and allocated to the Western System.

Characteristics

While these engines were also built on bar frames like the previous two 6th Class versions, they were slightly larger, with larger boilers and with NaN0NaN0 diameter cylinders compared to the 170NaN0 diameter cylinders of all earlier 6th Class locomotives. Like the two Class 6F locomotives, a visually obvious distinguishing feature was their higher mounted running boards without the need for coupled wheel fairings.[2]

The locomotive was equipped with Richardson balanced slide valves. The boiler barrel and the outside of the firebox were of Coatesville steel. The boiler feed was by two Cape pattern Gresham & Craven's no. 8 injectors, while the engine used Gresham & Craven's patent sanding gear and a Nathan no. 8 double sight feed cylinder lubricator. It had steam brakes on two pairs of coupled wheels, while the Type WE tender was equipped with a vacuum brake for itself and the train. The whistles were one 30NaN0 and one 40NaN0 Star Chime no. 3 types.[2]

The firebox was 950NaN0 long, NaN0NaN0 wide, NaN0NaN0 deep in front and NaN0NaN0 deep at the back. The firebox itself was of copper, with a rocking style firegrate and a hopper-type ash pan.[2]

The smokebox was equipped with openings on its sides near the front, with covers which each had a handle by which it could be opened with a half turn to give direct access to the inside of the smokebox. This was most likely to facilitate cleaning of the spark arrestor screens to overcome clogging without having to open the smokebox door.

Class 6 sub-classes

When the Union of South Africa was established on 31 May 1910, the three Colonial government railways (CGR, Natal Government Railways and Central South African Railways) were united under a single administration to control and administer the railways, ports and harbours of the Union. Although the South African Railways and Harbours came into existence in 1910, the actual classification and renumbering of all the rolling stock of the three constituent railways were only implemented with effect from 1 January 1912.[1] [3]

When these eight locomotives were assimilated into the South African Railways (SAR) in 1912, they were renumbered in the range from 606 to 613 and designated Class 6G.[1] [4]

The rest of the CGR’s 6th Class locomotives, together with 6th Class locomotives which had been 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 locomotives became SAR Classes 6, 6A to 6F, 6H and 6J to 6L, the locomotives became Class 6Y and the locomotives became Class 6Z.[4]

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. It went on to see service in all parts of the country, except in Natal, and was used on all types of traffic.

The Class 6G remained in service for sixty years, the last one being withdrawn from service at East London in 1961.

Notes and References

  1. 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)
  2. Schenectady Ten Wheel Locomotives for Cape Government Railways. Railway and Locomotive Engineering – A Practical Journal of Railway Motive Power and Rolling Stock. March 1901. 13. 3. 131–132. 23 December 2012.
  3. The South African Railways - Historical Survey. Editor George Hart, Publisher Bill Hart, Sponsored by Dorbyl Ltd., Published c. 1978, p. 25.
  4. South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended