Data from DeGolyer, Volume 79, pp. 458+. (Thanks to Teemu Koivumaki for his 4 Janaury 2025 email noting the Nasmyth Wilson locomotives that repeated the design tthree years later.) Works numbers were 60906-60915 in July 1929.
Ten superheated Mikados probably added a good deal of power to the T-P. They had generously sized fireboxes, whose direct heating surface area included 48 sq ft (4.45 sq m) in the combustion chamber and 23 sq ft (2.15 sq m) in the arch tubes. A comparably scaled superheater created hotter steam that was admitted to the cylinders through 11" (279 mm) piston valves.
These were left-hand drive engines with slightly flared copper-top stacks.
The Nasmyth Wilson locomotives that repeated the design appear in Locobase 20310.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 281/JF11 |
| Locobase ID | 15465 |
| Railroad | Tientsin-Pukow |
| Country | China |
| Whyte | 2-8-2 |
| Number in Class | 10 |
| Road Numbers | 281-290 |
| Gauge | Std |
| Number Built | 10 |
| Builder | Baldwin |
| Year | 1929 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 15 / 4.57 |
| Engine Wheelbase (ft / m) | 31.83 / 9.70 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.47 |
| Overall Wheelbase (engine & tender) (ft / m) | 46.25 / 14.10 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 140,000 / 63,503 |
| Engine Weight (lbs / kg) | 190,000 / 86,183 |
| Tender Loaded Weight (lbs / kg) | 124,150 / 56,314 |
| Total Engine and Tender Weight (lbs / kg) | 314,150 / 142,497 |
| Tender Water Capacity (gals / ML) | 6600 / 25 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 10.10 / 9 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 58 / 29 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 54 / 1372 |
| Boiler Pressure (psi / kPa) | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 20" x 28" / 508x711 |
| Tractive Effort (lbs / kg) | 35,259 / 15993.23 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.97 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 139 - 2" / 51 |
| Flues (number - dia) (in / mm) | 24 - 5.375" / 137 |
| Flue/Tube length (ft / m) | 16.25 / 4.95 |
| Firebox Area (sq ft / m2) | 225 / 20.90 |
| Grate Area (sq ft / m2) | 43.50 / 4.04 |
| Evaporative Heating Surface (sq ft / m2) | 1947 / 180.88 |
| Superheating Surface (sq ft / m2) | 443 / 41.16 |
| Combined Heating Surface (sq ft / m2) | 2390 / 222.04 |
| Evaporative Heating Surface/Cylinder Volume | 191.24 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 8700 |
| Same as above plus superheater percentage | 10,353 |
| Same as above but substitute firebox area for grate area | 53,550 |
| Power L1 | 12,480 |
| Power MT | 786.10 |