Data from Krupp im Dienst der Dampflokomotive (Essen, Germany: 1940), p 102. See also "Datong-Puzhou railway explained" on the Everything Explained at [], last accessed 30 November 2025. Works numbers were 1395-1397, 1433-1442 in 1934.
Krupp's builder's photograph of the lead engine in this metric Mogul class shows an upright, stubby profile rolling on small drivers. It made up much of the motive power stud for the Tongpu railway in Shanxi Province that opened the year before.
Although it ultimately amassed 865 km (537 miles), but building it took years from 1933 to 1940 before the Northern Tongpu and Southern Tongpu met at Shanxi's centrally located capital of Taiyuan. Its later name reflects its final diagonal route from Datong in the northeast to Puzhou in the southwest (Read the Everything Explained to see the history of 1930s China in a single railway.)
NB: The calculated superheater to combined heating surface ratio almost certainly derives from calculating the tube heating surface from the fire side. To compare with most North American and British Empire locomotives would increase CHS by 8-10% and lower the superheat ratio commensurately.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 104 |
| Locobase ID | 21286 |
| Railroad | TongPu |
| Country | China |
| Whyte | 2-6-0 |
| Number in Class | 13 |
| Road Numbers | 104-116 |
| Gauge | Metre |
| Number Built | 13 |
| Builder | Krupp |
| Year | 1934 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | |
| Engine Wheelbase (ft / m) | |
| Ratio of driving wheelbase to overall engine wheelbase | |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 48,943 / 22,200 |
| Engine Weight (lbs / kg) | 62,170 / 28,200 |
| Tender Loaded Weight (lbs / kg) | 49,604 / 22,500 |
| Total Engine and Tender Weight (lbs / kg) | 111,774 / 50,700 |
| Tender Water Capacity (gals / ML) | 10 / 12.12 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2.50 / 5 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 27 / 13.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 43.30 / 1100 |
| Boiler Pressure (psi / kPa) | 191 / 1300 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 15.75" x 19.69" / 400x500 |
| Tractive Effort (lbs / kg) | 18,313 / 8306.65 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 2.67 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | |
| Grate Area (sq ft / m2) | 16.15 / 1.50 |
| Evaporative Heating Surface (sq ft / m2) | 649 / 60.30 |
| Superheating Surface (sq ft / m2) | 282 / 26.20 |
| Combined Heating Surface (sq ft / m2) | 931 / 86.50 |
| Evaporative Heating Surface/Cylinder Volume | 146.17 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 3085 |
| Same as above plus superheater percentage | 4010 |
| Same as above but substitute firebox area for grate area | |
| Power L1 | |
| Power MT | |