Indian Railways class WP
The WP was created after the Second World War as the standard express locomotive of Indian Railways. These Pacifics stood out because of their streamlining on the smokebox and were designed to be able to haul heavy trains at up to 120 km/h, even with low-calorie coal. Compared to the similarly powerful pre-war XC, they were a little heavier, but had a lower maximum axle load due to a different weight distribution.
They were initially faster than the existing diesel locomotives and hauled the most important express trains. Between 1947 and 1967, 755 locomotives were built, more than half of which came from North America. Others were made in Poland and Austria. It wasn't until 1963 that 259 were built in India, which were around five tons heavier. Most remained in service into the 1980s and some even survived into the 1990s.
Technical data
General
- Built
- 1947-1967
- Manufacturers
- Baldwin, Canadian Locomotive Co., Montreal Locomotive Works, Fablok, Floridsdorf, Chittaranjan
- Wheel arrangement
- 4-6-2 (Pacific)
- Gauge
- 1,676 mm (Indian broad gauge)
Dimensions and weights
- Length
- 23.61 m
- Wheelbase
- 11.05 m
- Total wheelbase
- 20.80 m
- Service mass
- 103.1 t
- Adhesion mass
- 55.1 t
- Total mass
- 176.2 t
- Rigid wheelbase
- 3.73 m
- Axle load
- 18.8 t
- Water capacity
- 25,003 l
- Fuel capacity
- 15.2 t (coal)
Boiler
- Grate area
- 4.278 m²
- Firebox surface
- 23.69 m²
- Tube heating surface
- 195.282 m²
- Evaporative heating surface
- 218.973 m²
- Superheater surface
- 67.355 m²
- Total heating surface
- 286.3 m²
Power plant
- Driver diameter
- 1,702 mm
- Boiler pressure
- 14.5 bar
- Expansion type
- simple expansion
- Cylinders
- two, 514 x 711 mm
Power
- Power source
- steam
- Indicated power
- 1,998 kW (2,717 PS)
- Top speed
- 121 km/h
- Starting effort
- 136.1 kN
Calculated values
- Factor of adhesion
- 1 : 3.97
- Optimal speed
- 90 km/h
- Power-to-weight ratio
- 19.4 kW/t
- Heating Surface Equivalent
- 472.1 m²
- Cylinder volume/HSE
- 1 : 625.99
- Adhesive weight/Total
- 1 : 1.87
- Tractive force/Heating surface
- 1 : 9.93
- Grate area/Heating surface
- 1 : 66.93
- Firebox/Tube surface
- 1 : 8.24
- Total/Superheater
- 1 : 3.25