Imperial Government Railways/CSAR 2-8-4 Locomotives in South_Africa

Class Details by Steve Llanso of Sweat House Media

Class Western Australians (Locobase 20903)

Data from Howell, Comparative Statistics of the Australasian Railways, Journal of the Royal Statistical Society, March 1899, pp. 96-97; "CSAR Class C 2-8-4T" in the Wikipedia encyclopedia at [], last accessed 12 June 2021; and Leon Oberg, Locomotives of Australia: 1850s - 2007 (Rosenberg Publishing, 2007), pp. 96-97. Works numbrs 5987-5902 in 1900.

24 of this design were delivered to the Western Australia Railways in 1893; see Locobase 9567). In 1900, the final six due to go to the WAGR were diverted by the British government for the IMR to use in South Africa during the Boer War.

Later, they served the Central South African as their C-class (road numbers 203-208) although they didn't last in that service. Wikipedia explains that the class "were not popular with the crews." Small drivers and short coupling rods combined to roughen the ride at speed. Moreover, the footplate was cramped by the side tanks, which extended into the cab.

All six soon entered shunting service. By 1904, three of the class had been sold to collieries (204 & 208 to Clydesdale Collieries, 205 to Oogies Colliery). These lasted for quite some time with 204 putting in nearly 70 more years. The other three were simply scrapped by 1910.

On the other hand, Clydesdale's 204 ran on for decades. A new boiler fitted in 1939 allowed an 20 psi increase in pressure to 180 psi (12.4 bar). Seeing no reason to retire the engine (it was, after all, long since paid for), CC ran the 204 until 1972.

Beginning in 1915, 2 were converted, gaining a superheated in the process and a total of 5 had been made over by 1929. But the superheater's advantages were more than outweighed by its maintenance demands and all 5 engines regained their saturated boilers. According to Oberg, the class was, not surprisingly, run into the ground by the demands of traffic induced by World War II and some were scrapped soon afterward. The departures of others of the class were considerably delayed by the need for heavy switchers and extra power for heavy passenger demands (like race day, e.g.). The last K-class engine was withdrawn in 1964.

Principal Dimensions by Steve Llanso of Sweat House Media

ClassWestern Australians
Locobase ID20903
RailroadImperial Government Railways/CSAR
CountrySouth Africa
Number in Class6
Road Numbers100-106/203-208
Number Built6
BuilderNeilson & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)11.25 / 3.43
Engine Wheelbase (ft / m)28 / 8.53
Ratio of driving wheelbase to overall engine wheelbase 0.40
Overall Wheelbase (engine & tender) (ft / m)28 / 8.53
Axle Loading (Maximum Weight per Axle) (lbs / kg)18,840 / 8546
Weight on Drivers (lbs / kg)73,920 / 33,530
Engine Weight (lbs / kg)118,720 / 53,851
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)118,720 / 53,851
Tender Water Capacity (gals / ML)2400 / 9.09
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 2.80 / 2.50
Minimum weight of rail (calculated) (lb/yd / kg/m)31 / 15.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)38 / 965
Boiler Pressure (psi / kPa)160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)17" x 21" / 432x533
Tractive Effort (lbs / kg)21,721 / 9852.49
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.40
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)12 / 3.66
Firebox Area (sq ft / m2)93.30 / 8.67
Grate Area (sq ft / m2)16.70 / 1.55
Evaporative Heating Surface (sq ft / m2)1013 / 94.11
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1013 / 94.11
Evaporative Heating Surface/Cylinder Volume183.62
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2672
Same as above plus superheater percentage2672
Same as above but substitute firebox area for grate area14,928
Power L12718
Power MT324.25

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