Hejaz Railway No. 21 to 23
Ottoman Empire 1951 3 produced
In 1951, Robert Stephenson & Hawthorns built three oil-fired Mikados for the Jordanian part of the Hejaz Railway. Their works numbers were 7431 to 7433 and the railway gave them the numbers 21 to 23. They were based on the Indian class YD, but were built for the gauge of 1,050 mm. The boiler had a Belpaire firebox and a Melesco superheater. Like the YD, they had cylinders of 17 by 24 inches, drivers of four feet and a boiler pressure of 180 psi, resulting in a starting tractive effort of 22,108 pounds. The line they operated on had inclines of two percent and curves with a radius of 100 metres. There they hauled trains between 200 and 350 tons at a maximum speed of 60 to 65 km/h (around 40 mph).
Technical data
General
- Built
- 1951
- Manufacturers
- Robert Stephenson & Hawthorns
- Wheel arrangement
- 2-8-2 (Mikado)
- Gauge
- 1,049 mm
Dimensions and weights
- Length
- 18.64 m
- Wheelbase
- 9.79 m
- Total wheelbase
- 15.82 m
- Service mass
- 56.5 t
- Adhesion mass
- 37.9 t
- Total mass
- 96.8 t
- Rigid wheelbase
- 4.09 m
- Axle load
- 11.6 t
- Water capacity
- 13,639 l
- Fuel capacity
- 7,503 l (oil)
Boiler
- Grate area
- 2.415 m²
- Firebox surface
- 12.356 m²
- Tube heating surface
- 115.943 m²
- Evaporative heating surface
- 128.299 m²
- Superheater surface
- 28.614 m²
- Total heating surface
- 156.9 m²
Power plant
- Driver diameter
- 1,219 mm
- Boiler pressure
- 12.4 bar
- Expansion type
- simple expansion
- Cylinders
- two, 432 x 610 mm
Power
- Power source
- steam
- Estimated power
- 820 kW (1,115 PS)
- Starting effort
- 98.3 kN
Calculated values
- Factor of adhesion
- 1 : 3.78
- Optimal speed
- 51 km/h
- Power-to-weight ratio
- 14.5 kW/t
- Heating Surface Equivalent
- 247.3 m²
- Cylinder volume/HSE
- 1 : 721.93
- Adhesive weight/Total
- 1 : 1.49
- Tractive force/Heating surface
- 1 : 13.09
- Grate area/Heating surface
- 1 : 64.97
- Firebox/Tube surface
- 1 : 9.38
- Total/Superheater
- 1 : 4.48
