Data from:
Svein Sando's Railway Site [] (9 June 2004)--(Later link: The Semaphore, accessed for link update 10 July 2022.)-- and the Jernbane (Iron Road) site http://jernbane.net (June 2004).
The Dunderland Iron Ore Company took delivery of these 4 saddle-tankers from Thune (B1 & B2) and Hamar (B3 & B4). In the world of Norwegian 2-axle tanks, these were the largest.
At the other end of their career line, the last was retired from the NSB on 11 May 1955
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Class 56 |
| Locobase ID | 6200 |
| Railroad | DIOC / NSB |
| Country | Norway |
| Whyte | 0-4-0ST |
| Number in Class | 4 |
| Road Numbers | B1-B4 / 496-499 |
| Gauge | Std |
| Number Built | 4 |
| Builder | several |
| Year | 1905 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 6.51 / 1.98 |
| Engine Wheelbase (ft / m) | 6.51 / 1.98 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 6.51 / 1.98 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 55,116 / 25,000 |
| Engine Weight (lbs / kg) | 55,116 / 25,000 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 713 / 2.70 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 1.80 / 2 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 46 / 23 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 40.50 / 1028 |
| Boiler Pressure (psi / kPa) | 134.90 / 930 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 13" x 19" / 330x483 |
| Tractive Effort (lbs / kg) | 9091 / 4123.61 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 6.06 |
| 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) | 8.07 / 0.75 |
| Evaporative Heating Surface (sq ft / m2) | 455 / 42.25 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 455 / 42.25 |
| Evaporative Heating Surface/Cylinder Volume | 155.88 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 1089 |
| Same as above plus superheater percentage | 1089 |
| Same as above but substitute firebox area for grate area | |
| Power L1 | |
| Power MT | |