Data from C&O 9-1936 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.See alos "Heavy Switchers Built for the C&O", Railway Mechanical Engineer, Volume 94, No 1 (January 1920), pp. 11-14. (Thanks to Chris Hohl for his 4 December 2017 supplying the link to the RME article and noting the original tender capacity, superheater and firebox heating surface areas.) Works numbers were 59980-59989 in January 1919 and 62197-62201 in February 1921.
These enormous switchers came to the C&O in two batches: 130-139 in 1919, 140-144 in 1921. Later tenders in some of the class would be fitted with coal boards that increased fuel capacity to 20 tons (18.14 metric tons). The RME reported the engine's firebox heating surface as 232 sq ft (21.55 sq m) including arch tubes, but the C&O's diagrams show a firebox are of 229 sq ft (21.27 sq m) with an additional 27 sq ft (2.51 sq m) of arch tubes.
The RME noted that the small drivers and 28" stroke in the cylinders combined with "large crank pins necessary for a engine of this high power made the question of clearance of main rod straps and eccentric cranks a rather difficult problem." To achieve the required height of the eccentric crank above the rails, the builder made the main crank pin eccentric. (In other words, viewed in cross-section, the hole in the crank boss was off-center.)
They were well-suited to the job of assembling the long coal trains that would be hauled by the big articulateds in which the railroad specialized. The last wasn't retired until 1956.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | C-12 |
| Locobase ID | 12634 |
| Railroad | Chesapeake & Ohio (C&O) |
| Country | USA |
| Whyte | 0-10-0 |
| Number in Class | 15 |
| Road Numbers | 50-64/130-144 |
| Gauge | Std |
| Number Built | 15 |
| Builder | Alco-Richmond |
| Year | 1919 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 19 / 5.79 |
| Engine Wheelbase (ft / m) | 19 / 5.79 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 60.27 / 18.37 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 59,400 / 26,943 |
| Weight on Drivers (lbs / kg) | 295,000 / 133,810 |
| Engine Weight (lbs / kg) | 295,000 / 133,810 |
| Tender Loaded Weight (lbs / kg) | 193,000 / 87,543 |
| Total Engine and Tender Weight (lbs / kg) | 488,000 / 221,353 |
| Tender Water Capacity (gals / ML) | 10,000 / 37.88 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 15 / 14 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 98 / 49 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 51 / 1295 |
| Boiler Pressure (psi / kPa) | 185 / 1280 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 27" x 28" / 686x711 |
| Tractive Effort (lbs / kg) | 62,937 / 28547.78 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.69 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 217 - 2.25" / 57 |
| Flues (number - dia) (in / mm) | 45 - 5.5" / 140 |
| Flue/Tube length (ft / m) | 18.08 / 5.51 |
| Firebox Area (sq ft / m2) | 256 / 23.78 |
| Grate Area (sq ft / m2) | 72.80 / 6.76 |
| Evaporative Heating Surface (sq ft / m2) | 3715 / 345.13 |
| Superheating Surface (sq ft / m2) | 945 / 87.79 |
| Combined Heating Surface (sq ft / m2) | 4660 / 432.92 |
| Evaporative Heating Surface/Cylinder Volume | 200.16 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 13,468 |
| Same as above plus superheater percentage | 16,162 |
| Same as above but substitute firebox area for grate area | 56,832 |
| Power L1 | 11,438 |
| Power MT | 427.40 |