Data from Gavin Hamilton, "A Complete list of Garratt Locomotive dimensions", (first accessed 2005, last accessed 15 August 2021 at []. See also Robert Hall, "A Garland of Islands, Part 6, Africa 1" on Rob Dickinson's International Website at [], last accessed 14 August 2021. Works numbers were 6381-6383 in 1927.
These were big locomotives to have on an Indian Ocean island, but Garratts operated in a wider variety of locations than almost any other locomotive type. Robert Hall conceded the unlikely location but explained the trio's presence by noting that traffic on the "Midland" line, from the capital Port Louis south-east through the mountainous centre of the island" had increased so much that it required "multiple-heading" (i.e., at least two but sometimes more) by tank locomotives.
The MGR's response was to buy this "relative 'super-power'" set in 1927. Taking full advantage of the track and loading gauges, the engines dwarfed any of the other locomotives on the island. Like virtually all Garratts built by Beyer, Peacock, this design featured outside constant-lead radial valve gear, four simple-expansion cylinders using piston valves, a square-shouldered Belpaire firebox, and superheater. They were rated at 350 tons trailing load up a 2 1/2% grade.
"As things turned out," continued Hall, "the Depression of the 1930s was shortly to begin, meaning less trade and less freight to haul: from then on, the Garratts had not so much work as originally anticipated, and toward the end of the system's life they were seldom used."
Principal Dimensions by Steve Llanso of Middle Run Media | |
---|---|
Class | 60 |
Locobase ID | 700 |
Railroad | Mauritius Railway |
Country | Mauritius |
Whyte | 2-8-0+0-8-2 |
Number in Class | 3 |
Road Numbers | 60-62 |
Gauge | Std |
Number Built | 3 |
Builder | Beyer, Peacock |
Year | 1927 |
Valve Gear | Walschaert |
Locomotive Length and Weight | |
Driver Wheelbase (ft / m) | 23.08 / 7.03 |
Engine Wheelbase (ft / m) | 71.67 / 21.85 |
Ratio of driving wheelbase to overall engine wheelbase | 0.32 |
Overall Wheelbase (engine & tender) (ft / m) | 80 / 24.38 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 36,176 / 16,409 |
Weight on Drivers (lbs / kg) | 285,488 / 129,495 |
Engine Weight (lbs / kg) | 346,640 / 157,233 |
Tender Loaded Weight (lbs / kg) | |
Total Engine and Tender Weight (lbs / kg) | |
Tender Water Capacity (gals / ML) | 6000 / 22.73 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 6.70 / 6.10 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 59 / 29.50 |
Geometry Relating to Tractive Effort | |
Driver Diameter (in / mm) | 46 / 1168 |
Boiler Pressure (psi / kPa) | 200 / 1380 |
High Pressure Cylinders (dia x stroke) (in / mm) | 19" x 24" / 483x610 (4) |
Tractive Effort (lbs / kg) | 64,038 / 29047.18 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.46 |
Heating Ability | |
Tubes (number - dia) (in / mm) | 227 - 2" / 51 |
Flues (number - dia) (in / mm) | 42 - 5.25" / 133 |
Flue/Tube length (ft / m) | 12.85 / 3.92 |
Firebox Area (sq ft / m2) | 213.50 / 19.83 |
Grate Area (sq ft / m2) | 53.90 / 5.01 |
Evaporative Heating Surface (sq ft / m2) | 2480 / 230.40 |
Superheating Surface (sq ft / m2) | 523 / 48.59 |
Combined Heating Surface (sq ft / m2) | 3003 / 278.99 |
Evaporative Heating Surface/Cylinder Volume | 157.44 |
Computations Relating to Power Output (More Information) | |
Robert LeMassena's Power Computation | 10,780 |
Same as above plus superheater percentage | 12,613 |
Same as above but substitute firebox area for grate area | 49,959 |
Power L1 | 8035 |
Power MT | 496.39 |