Otavi Mining 2-8-2 Locomotives in South_Africa
Class Details by Steve Llanso of Sweat House Media
Class NG15 (Locobase 999)
Data from Wikipedia--[
] accessed 12/12/12. See also David Payling, "Narrow gauge locos of South West Africa - Part 3 NG15 2-8-2", Continental Modeller (May 2009), pp. 278-280. Societe Franco-Belge, Raismes, France built 120-124 in 1949 and 132-136 in 1952 (works numbers were 2667-2671, 2682-2686). Henschel's post-World War II orders amounted to 144-148 in 1957 (29585-29589).
So small were the drivers on this engine that they disappeared from view behind the large counterweights and outside plate frames of thie dimunitive freight engine. Note the relatively short stroke.
Known as "Kalaharis", the class
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | NG15 |
| Locobase ID | 999 |
| Railroad | Otavi Mining |
| Country | South Africa |
| Whyte | 2-8-2 |
| Number in Class | 21 |
| Road Numbers | 120-124, 132-136, 144-148 |
| Gauge | 2' |
| Number Built | 21 |
| Builder | several |
| Year | 1949 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 9.58 / 2.92 |
| Engine Wheelbase (ft / m) | 20.11 / 6.13 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.48 |
| Overall Wheelbase (engine & tender) (ft / m) | 44.65 / 13.61 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 15,148 / 6871 |
| Weight on Drivers (lbs / kg) | 60,592 / 27,484 |
| Engine Weight (lbs / kg) | 82,208 / 37,289 |
| Tender Loaded Weight (lbs / kg) | 70,001 / 31,752 |
| Total Engine and Tender Weight (lbs / kg) | 152,209 / 69,041 |
| Tender Water Capacity (gals / ML) | 3403 / 12.89 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 6.20 / 6 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 25 / 12.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 33.90 / 860 |
| Boiler Pressure (psi / kPa) | 171.10 / 1180 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 15.75" x 17.76" / 400x451 |
| Tractive Effort (lbs / kg) | 18,901 / 8573.36 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.21 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 94 - 1.748" / 44.4 |
| Flues (number - dia) (in / mm) | 15 - 4.724" / 120 |
| Flue/Tube length (ft / m) | 11.81 / 3.60 |
| Firebox Area (sq ft / m2) | 68.03 / 6.32 |
| Grate Area (sq ft / m2) | 16.68 / 1.55 |
| Evaporative Heating Surface (sq ft / m2) | 796 / 73.95 |
| Superheating Surface (sq ft / m2) | 180 / 16.72 |
| Combined Heating Surface (sq ft / m2) | 976 / 90.67 |
| Evaporative Heating Surface/Cylinder Volume | 198.76 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2854 |
| Same as above plus superheater percentage | 3368 |
| Same as above but substitute firebox area for grate area | 13,735 |
| Power L1 | 6653 |
| Power MT | 968.27 |