Data from "2-6-4 Tank Locomotive, Buenos Ayres [sic] Midland Ry.", Locomotive Magazine, Volume XXI [21] (15 January 1915), p. 4.
The BAM used 80-lb/yd (40 kg/metre) rail and added these tanks to spread the load of a larger boiler. Inside-admission piston valves supplied superheated steam to the cylinders and the Belpaire firebox gave it a typically squared-off look. Its firebox was one of the largest in a metre-gauge tank locomotive.
The class served suburban traffic until the system electrified in the late 1930s.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | G |
| Locobase ID | 20413 |
| Railroad | Buenos Aires Midland |
| Country | Argentina |
| Whyte | 2-6-4T |
| Number in Class | 5 |
| Road Numbers | 201 |
| Gauge | Metre |
| Number Built | 5 |
| Builder | Hunslet Engine Co |
| Year | 1914 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 11 / 3.35 |
| Engine Wheelbase (ft / m) | 30 / 9.14 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.37 |
| Overall Wheelbase (engine & tender) (ft / m) | 30 / 9.14 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | |
| Engine Weight (lbs / kg) | 128,800 / 58,423 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | 128,800 / 58,423 |
| Tender Water Capacity (gals / ML) | 3300 / 12.50 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 6.10 / 6 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 54 / 1372 |
| Boiler Pressure (psi / kPa) | 150 / 1030 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 17" x 24" / 432x610 |
| Tractive Effort (lbs / kg) | 16,377 / 7428.49 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 97 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 11.80 / 3.60 |
| Firebox Area (sq ft / m2) | 121 / 11.24 |
| Grate Area (sq ft / m2) | 16 / 1.49 |
| Evaporative Heating Surface (sq ft / m2) | 813 / 75.53 |
| Superheating Surface (sq ft / m2) | 206 / 19.14 |
| Combined Heating Surface (sq ft / m2) | 1019 / 94.67 |
| Evaporative Heating Surface/Cylinder Volume | 128.95 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2400 |
| Same as above plus superheater percentage | 2880 |
| Same as above but substitute firebox area for grate area | 21,780 |
| Power L1 | 7006 |
| Power MT | |