Natal Navigation Colliery Beyer-Garratt Locomotives in South_Africa
Class Details by Steve Llanso of Sweat House Media
Class unknown (Locobase 20932)
Data from "'Garratt' Patent Locomotives for the New Cape Central Railway", Volume XXIX [29] (15 September 1923), p. 256-257; and "Natal Navigation Colliery, Design No.1125", Beyer-Garrrat Patent Articulated Locomotives (Manchester, England: Beyer-Peacock & Company Limited, 1931), archived on flickr's Historical Railway Images at [
], et seq, p. 47.. Virtually identical to the Trans-Zambezi locomotives. Works number was 6206 in 1924.
Natal Navigation Collieries and Estate Co purchased an engine that was identical to the New Cape Railway G-class Garratts (Locobase 747) and the Trans-Zambezi Garratts described in Locobase 718 . All had Walschaert gear, piston valves for all four simple-expansion cylinders, a superheater, and a Belpaire firebox.
The NNC locomotive hauled coal trains from the pits to the main line which branched off from Hatting Spruit on the SAR.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | unknown |
| Locobase ID | 20932 |
| Railroad | Natal Navigation Colliery |
| Country | South Africa |
| Whyte | 2-6-2+2-6-2 |
| Number in Class | 1 |
| Road Numbers | |
| Gauge | 3'6" |
| Number Built | 1 |
| Builder | Beyer, Peacock |
| Year | 1924 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 16 / 4.88 |
| Engine Wheelbase (ft / m) | 35.33 / 10.77 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.45 |
| Overall Wheelbase (engine & tender) (ft / m) | 65.25 / 19.89 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 23,520 / 10,669 |
| Weight on Drivers (lbs / kg) | 141,120 / 64,011 |
| Engine Weight (lbs / kg) | 212,404 / 96,345 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 3600 / 13.64 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4.50 / 4.10 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 39 / 19.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 42 / 1067 |
| Boiler Pressure (psi / kPa) | 180 / 1240 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 15" x 22" / 381x559 (4) |
| Tractive Effort (lbs / kg) | 36,064 / 16358.37 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.91 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 225 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | 24 - 5.5" / 140 |
| Flue/Tube length (ft / m) | 11.12 / 3.39 |
| Firebox Area (sq ft / m2) | 157 / 14.59 |
| Grate Area (sq ft / m2) | 33.90 / 3.15 |
| Evaporative Heating Surface (sq ft / m2) | 1687 / 156.73 |
| Superheating Surface (sq ft / m2) | 293 / 27.22 |
| Combined Heating Surface (sq ft / m2) | 1980 / 183.95 |
| Evaporative Heating Surface/Cylinder Volume | 187.46 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 6102 |
| Same as above plus superheater percentage | 7017 |
| Same as above but substitute firebox area for grate area | 32,499 |
| Power L1 | 7153 |
| Power MT | 670.48 |