Central South African 4-6-4 Locomotives in South_Africa
Class Details by Steve Llanso of Sweat House Media
Class Class F (Locobase 2718)
Data from Holland (1972, I)l; and "South African Class F 4-6-4T" in Wikipedia at [
], last accessed 16 June 2024. Works numbers were 1908-1915 in 1903.
This tank engine used the same boiler, cylinders, and motion as the Pacific delivered to the CSAR at the same time (Locobase 2914). Differences in water and coal capacity underscore the short-haul role of this variation as this class served commuters south of Pretoria on the 85 km (53 miles) West-East line between Springs and Randfontein Their livery and polished brasswork earned them the nickname of "Chocolate Boxes."
Holland wrote that the designer, PA Hyde, told him in a letter that the F class and its 9th class tender-engine counterpart were two of his most successful designs. Yet both classes soon began to show frame cracks between the cylinders and the first coupled axle. One-half inch (13 mm) "flitch" plates sandwiching each frame relieved the problem.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Class F |
| Locobase ID | 2718 |
| Railroad | Central South African |
| Country | South Africa |
| Whyte | 4-6-4T |
| Number in Class | 8 |
| Road Numbers | 260-267/78-85 |
| Gauge | 3'6" |
| Number Built | 8 |
| Builder | Vulcan Foundry |
| Year | 1903 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 11 / 3.35 |
| Engine Wheelbase (ft / m) | 34.09 / 10.39 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.32 |
| Overall Wheelbase (engine & tender) (ft / m) | 34.09 / 10.39 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 29,120 / 13,209 |
| Weight on Drivers (lbs / kg) | 87,360 / 39,626 |
| Engine Weight (lbs / kg) | 176,960 / 80,268 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | 176,960 / 80,268 |
| Tender Water Capacity (gals / ML) | 2160 / 8.18 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3.30 / 3 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 49 / 24.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 54 / 1372 |
| Boiler Pressure (psi / kPa) | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 26" / 457x660 |
| Tractive Effort (lbs / kg) | 26,520 / 12029.28 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.29 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 205 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 12.59 / 3.84 |
| Firebox Area (sq ft / m2) | 131 |
| Grate Area (sq ft / m2) | 21.75 / 2.02 |
| Evaporative Heating Surface (sq ft / m2) | 1481 / 137.64 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1481 / 137.64 |
| Evaporative Heating Surface/Cylinder Volume | 193.40 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 4350 |
| Same as above plus superheater percentage | 4350 |
| Same as above but substitute firebox area for grate area | 26,200 |
| Power L1 | 5021 |
| Power MT | 380.13 |