Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 30, p 185. Works numbers 30078, 30125 in February 1907 and 32270-32271 in November.
Martin Coombs noted that at least the 10 arrived with slide valves and inside link motion. When the C de P fitted the class with piston valves, they also replaced the Stephenson gear with outside Walschaert's constant-lead gear.
Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 44, p 217. See Locobase 13083 for a brief description of this high-altitude line. Works numbers were 39122-39123 in January 1913.
More frankly drag-freight engines than the four Mikados shown in Locobase 12084, this pair served the coal mine branch that ended at Quishuarcancha. A note in the specs says that "Hereafter apply Walschaert valve gear". It's not clear if these two were retrofitted.
| Principal Dimensions by Steve Llanso of Middle Run Media | ||
|---|---|---|
| Class | 10 | 40 |
| Locobase ID | 13084 | 13085 |
| Railroad | Cerro de Pasco | Cerro de Pasco |
| Country | Peru | Peru |
| Whyte | 2-8-2 | 2-8-2 |
| Number in Class | 4 | 2 |
| Road Numbers | 10-12, 14 | 40-41 |
| Gauge | Std | Std |
| Number Built | 4 | 2 |
| Builder | Burnham, Williams & Co | Baldwin |
| Year | 1907 | 1913 |
| Valve Gear | Stephenson | Stephenson |
| Locomotive Length and Weight | ||
| Driver Wheelbase (ft / m) | 14 / 4.27 | 12 / 3.66 |
| Engine Wheelbase (ft / m) | 28.83 / 8.79 | 25.83 / 7.87 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.49 | 0.46 |
| Overall Wheelbase (engine & tender) (ft / m) | 55.67 / 16.97 | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | ||
| Weight on Drivers (lbs / kg) | 122,000 / 55,338 | 125,000 / 56,699 |
| Engine Weight (lbs / kg) | 156,000 / 70,760 | 158,000 / 71,668 |
| Tender Loaded Weight (lbs / kg) | 100,000 / 45,359 | 100,000 / 45,359 |
| Total Engine and Tender Weight (lbs / kg) | 256,000 / 116,119 | 258,000 / 117,027 |
| Tender Water Capacity (gals / ML) | 5000 / 18.94 | 5000 / 18.94 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 10 | 10 / 9 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 51 / 25.50 | 52 / 26 |
| Geometry Relating to Tractive Effort | ||
| Driver Diameter (in / mm) | 52 / 1321 | 42 / 1067 |
| Boiler Pressure (psi / kPa) | 180 / 1240 | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 20" x 26" / 508x660 | 21" x 22" / 533x559 |
| Tractive Effort (lbs / kg) | 30,600 / 13879.94 | 39,270 / 17812.59 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.99 | 3.18 |
| Heating Ability | ||
| Tubes (number - dia) (in / mm) | 192 - 2.25" / 57 | 300 - 2" / 51 |
| Flues (number - dia) (in / mm) | ||
| Flue/Tube length (ft / m) | 17.67 / 5.39 | 14.50 / 4.42 |
| Firebox Area (sq ft / m2) | 139 / 12.92 | |
| Grate Area (sq ft / m2) | 36.80 / 3.42 | 38.50 / 3.58 |
| Evaporative Heating Surface (sq ft / m2) | 2403 / 223.33 | |
| Superheating Surface (sq ft / m2) | ||
| Combined Heating Surface (sq ft / m2) | 2403 / 223.33 | |
| Evaporative Heating Surface/Cylinder Volume | 272.47 | |
| Computations Relating to Power Output (More Information) | ||
| Robert LeMassena's Power Computation | 6624 | 7700 |
| Same as above plus superheater percentage | 6624 | 7700 |
| Same as above but substitute firebox area for grate area | 27,800 | |
| Power L1 | 4918 | |
| Power MT | 346.95 | |