Tanganjika Railways class MK
East African class 25
Tanzania 1925 11 produced
In 1925 and 1926, Vulcan Foundry built eleven metre-gauge Mikados for the Tanganyika Railways which were designated class MK. The boiler pressure was relatively low at 160 psi, what was compensated for by the superheater. They had drivers of 54 inches and three cylinders with a diameter of 18 inches, what ensured a high pulling power. Originally they carried the numbers 206 to 216 and were later renamed to 400 to 410. Under the East African Railways, they became class 25.
Technical data
General
- Built
- 1925-1926
- Manufacturers
- Vulcan Foundry
- Wheel arrangement
- 2-8-2 (Mikado)
- Gauge
- 1,000 mm (Meter gauge)
Dimensions and weights
- Wheelbase
- 8.15 m
- Total wheelbase
- 14.50 m
- Service mass
- 58.7 t
- Adhesion mass
- 40.6 t
- Total mass
- 87.9 t
- Rigid wheelbase
- 3.66 m
- Water capacity
- 11,364 l
- Fuel capacity
- 7.3 t (wood)
Boiler
- Grate area
- 2.508 m²
- Firebox surface
- 12.914 m²
- Tube heating surface
- 121.331 m²
- Evaporative heating surface
- 134.245 m²
- Superheater surface
- 27.592 m²
- Total heating surface
- 161.8 m²
Power plant
- Driver diameter
- 1,372 mm
- Boiler pressure
- 11 bar
- Expansion type
- simple expansion
- Cylinders
- three, 457 x 584 mm
Power
- Power source
- steam
- Estimated power
- 746 kW (1,014 PS)
- Starting effort
- 125.2 kN
Calculated values
- Factor of adhesion
- 1 : 3.18
- Optimal speed
- 37 km/h
- Power-to-weight ratio
- 12.7 kW/t
- Heating Surface Equivalent
- 254.0 m²
- Cylinder volume/HSE
- 1 : 1,132.80
- Adhesive weight/Total
- 1 : 1.44
- Tractive force/Heating surface
- 1 : 16.16
- Grate area/Heating surface
- 1 : 64.53
- Firebox/Tube surface
- 1 : 9.40
- Total/Superheater
- 1 : 4.87
