Data from "Recent Belgian Locomotives," The Locomotive & Railway Carriage & Wagon Review, Vol III (May 1898), p. 70.
The author explains that this is a successor class to the Type 12s (Locobase 2568) that ran over most of the lines at the time. Road numbers included 911-912, 922, 943, 949, 1454, 2092-2100, 2220-2229. Among the changes were the adoption of Serve boiler tubes, a higher boiler pressure, and a conical stack with lip. The heavy outside frame remained.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Series 12bis |
| Locobase ID | 10088 |
| Railroad | Belgian State Railways |
| Country | Belgium |
| Whyte | 2-4-2 |
| Number in Class | 26 |
| Road Numbers | 911+ |
| Gauge | Std |
| Number Built | 26 |
| Builder | |
| Year | 1897 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 5.58 / 1.70 |
| Engine Wheelbase (ft / m) | 10.99 / 3.35 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.51 |
| Overall Wheelbase (engine & tender) (ft / m) | 10.99 / 3.35 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | |
| Engine Weight (lbs / kg) | 111,995 / 50,800 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 359 / 1.36 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 82.70 / 2100 |
| Boiler Pressure (psi / kPa) | 175.50 / 1210 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 19.69" x 23.62" / 500x600 |
| Tractive Effort (lbs / kg) | 16,518 / 7492.45 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | - 2.756" / 70 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | 126.97 / 11.80 |
| Grate Area (sq ft / m2) | 50.57 / 4.70 |
| Evaporative Heating Surface (sq ft / m2) | 1377 / 128 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1377 / 128 |
| Evaporative Heating Surface/Cylinder Volume | 165.42 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 8875 |
| Same as above plus superheater percentage | 8875 |
| Same as above but substitute firebox area for grate area | 22,283 |
| Power L1 | 5846 |
| Power MT | |