Data from "Une locomotive compound de 99 tonnes," Le Genie Civil , Tome XXXII, Nr 23 (9 Avril 1898), (reporting an item from Fortschritte des Eisenbahnwesens of January 1898), p. 386. See also Maurice Demoulin, TraitT pratique de la machine locomotive (Baudry, 1898), pp.404-405.
The report stated that at the time of its introduction, the Mallet was the largest of its type in service and was equipped with the largest grate. The boiler was fitted with internally finned, large-diameter Serve tubes. All four cylinders took steam from piston valves.
Data from "Heavy Banking Locomotives, Belgian State Railways", The Engineer, Volume 41, No. 5 (2 February 1906), pp. 109, 113.
The builder who put delivered the first six-axle mallet tank to the Belgian State Railways in 1897 (Locobase 15529) enlarged the design to increase the pushing power on the 1 in 33 (3%) grades between Liege and Ans on the Brussels-Antwerp line from Aix.
The engine used long-stroke piston valves to supply steam to both the HP and LP cylinders. Its enormous Belpaire firebox measured 3.70 m (12 ft 13/8") long, a Wootten-like 2.90 m (9 ft 4 1/2") wide, and a maximum height of 1.22 m (4 ft). This expanse of grate burned dust-like "slack" coal. Engineer's report claimed that the growing use of briquettes (compressed bricks of low-calorie fuel) would eliminate the need for such a big grate.
| Principal Dimensions by Steve Llanso of Middle Run Media | ||
|---|---|---|
| Class | unknown | unknown |
| Locobase ID | 15529 | 20977 |
| Railroad | Belgian State | Belgian State |
| Country | Belgium | Belgium |
| Whyte | 0-6-6-0T | 0-6-6-0T |
| Number in Class | 1 | |
| Road Numbers | ||
| Gauge | Std | Std |
| Number Built | 1 | |
| Builder | SA Saint Leonard | SA Saint Leonard |
| Year | 1897 | 1905 |
| Valve Gear | Walschaert | Walschaert |
| Locomotive Length and Weight | ||
| Driver Wheelbase (ft / m) | 30.68 / 9.35 | 19.69 / 6 |
| Engine Wheelbase (ft / m) | 30.68 / 9.35 | 19.69 / 6 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 30.68 / 9.35 | 30.76 / 9.38 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | ||
| Weight on Drivers (lbs / kg) | 218,257 / 99,000 | 245,484 / 111,350 |
| Engine Weight (lbs / kg) | 218,257 / 99,000 | 25,022 / 11,350 |
| Tender Loaded Weight (lbs / kg) | ||
| Total Engine and Tender Weight (lbs / kg) | ||
| Tender Water Capacity (gals / ML) | 2376 / 9 | 2376 / 9 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3.30 / 3 | 3.30 / 3 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 61 / 30.50 | 68 / 34 |
| Geometry Relating to Tractive Effort | ||
| Driver Diameter (in / mm) | 49.90 / 1268 | 53.50 / 1360 |
| Boiler Pressure (psi / kPa) | 213.20 / 1470 | 213.20 / 1470 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 21.65" x 25.59" / 550x650 | 19.69" x 25.59" / 500x650 |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 31.85" x 25.59" / 809x650 | 31.5" x 25.59" / 800x650 |
| Tractive Effort (lbs / kg) | 59,588 / 27028.69 | 48,328 / 21921.24 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.66 | 5.08 |
| Heating Ability | ||
| Tubes (number - dia) (in / mm) | 164 - 2.756" / 70 | |
| Flues (number - dia) (in / mm) | ||
| Flue/Tube length (ft / m) | 13.12 / 4 | |
| Firebox Area (sq ft / m2) | 161.46 / 15 | |
| Grate Area (sq ft / m2) | 75.35 / 7 | 84.50 / 7.85 |
| Evaporative Heating Surface (sq ft / m2) | 2799 / 260 | 2959 / 274.90 |
| Superheating Surface (sq ft / m2) | ||
| Combined Heating Surface (sq ft / m2) | 2799 / 260 | 2959 / 274.90 |
| Evaporative Heating Surface/Cylinder Volume | 256.71 | 328.10 |
| Computations Relating to Power Output (More Information) | ||
| Robert LeMassena's Power Computation | 16,065 | 18,015 |
| Same as above plus superheater percentage | 16,065 | 18,015 |
| Same as above but substitute firebox area for grate area | 34,423 | |
| Power L1 | 3102 | |
| Power MT | 167.15 | |