Data from Brian Hollingsworth and Arthur Cook, The Great Book of Trains (New York: Portland House, 1987), pp. 188-189; and "South African Class 19D 4-8-2" in Wikipedia at [], last accessed 9 March 2023.. Works numbers were 26959-26964 in 1951.
Intended to haul 500-ton trains up 1.25% grades and around curves of a 300-ft (91.4 m) radius, these engines accomplished that goal on a low axle loading while burning eucalyptus logs as fuel. Tender capacity came to 650 cu ft (18.5 cu m); see Locobase 2860 for Peter Ball's discussion of eucalyptys as a fuel..Wikipedia states that the tenders were Type MX tank wagon types with cylindrical water tanks designed by Dr M M Loubser. Their shape led to their "Torpedo tender" nikname.
The design was based on the South African Railways 19C/19D Mountain (Locobases 2958 and 12790); Locobase data comes from the o designation shown in the Wikipedia table.
The high-pitched boiler was headed by a front end that included a Kyala-Chapelon (Kylchap) blast-pipe as well as spark-arresting gear. Other "luxuries" included power reverse, steam-operated fire doors, compensated springing to balance the load on the drivers and trailing axle. The class worked express mail trains on Atlantic coast runs and on the Silva Porto - Luau section.
Only a civil war could stop these engines from serving out long lives.
Principal Dimensions by Steve Llanso of Middle Run Media | |
---|---|
Class | 11th class |
Locobase ID | 2604 |
Railroad | Benguela Railway |
Country | Angola |
Whyte | 4-8-2 |
Number in Class | 6 |
Road Numbers | 401-406 |
Gauge | 3'6" |
Number Built | 6 |
Builder | North British |
Year | 1951 |
Valve Gear | Walschaert |
Locomotive Length and Weight | |
Driver Wheelbase (ft / m) | 14.42 / 4.40 |
Engine Wheelbase (ft / m) | 32.25 / 9.83 |
Ratio of driving wheelbase to overall engine wheelbase | 0.45 |
Overall Wheelbase (engine & tender) (ft / m) | 76.66 / 23.37 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 31,248 / 14,174 |
Weight on Drivers (lbs / kg) | 123,984 / 56,238 |
Engine Weight (lbs / kg) | 178,304 / 80,877 |
Tender Loaded Weight (lbs / kg) | 164,304 / 74,527 |
Total Engine and Tender Weight (lbs / kg) | 342,608 / 155,404 |
Tender Water Capacity (gals / ML) | 6000 / 22.73 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 650 / 2460.30 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 52 / 26 |
Geometry Relating to Tractive Effort | |
Driver Diameter (in / mm) | 54 / 1372 |
Boiler Pressure (psi / kPa) | 204.50 / 1410 |
High Pressure Cylinders (dia x stroke) (in / mm) | 21" x 26" / 533x660 |
Tractive Effort (lbs / kg) | 36,909 / 16741.66 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.36 |
Heating Ability | |
Tubes (number - dia) (in / mm) | 76 - 2.25" / 57 |
Flues (number - dia) (in / mm) | 24 - 5.5" / 140 |
Flue/Tube length (ft / m) | 20.17 / 6.15 |
Firebox Area (sq ft / m2) | 139 / 12.91 |
Grate Area (sq ft / m2) | 36 / 3.34 |
Evaporative Heating Surface (sq ft / m2) | 1839 / 170.85 |
Superheating Surface (sq ft / m2) | 390 / 36.23 |
Combined Heating Surface (sq ft / m2) | 2229 / 207.08 |
Evaporative Heating Surface/Cylinder Volume | 176.44 |
Computations Relating to Power Output (More Information) | |
Robert LeMassena's Power Computation | 7362 |
Same as above plus superheater percentage | 8614 |
Same as above but substitute firebox area for grate area | 33,258 |
Power L1 | 10,673 |
Power MT | 759.13 |