Mexican State Railway class NR-1
Mexico 1937 10 produced
The Nacional de Mexico received ten Hudsons from ALCO in Schenectady in 1937. With an adhesive weight of 170.000 pounds, they were among the lightest North American locomotives with this wheel arrangement. Thanks to their oil firing, they were able to stay in service well into the 1960s. Number 2708 survives today, retired in 1963 and on display in the Plaza de las Tres Centurias in Aguascalientes.
Technical data
General
- Built
- 1937
- Manufacturers
- ALCO
- Wheel arrangement
- 4-6-4 (Hudson)
- Gauge
- 1,435 mm (Standard gauge)
Dimensions and weights
- Wheelbase
- 11.51 m
- Total wheelbase
- 21.06 m
- Service mass
- 132.4 t
- Adhesion mass
- 77.1 t
- Total mass
- 211.2 t
- Rigid wheelbase
- 3.96 m
- Axle load
- 25.7 t
- Water capacity
- 32,176 l
- Fuel capacity
- 15,282 l (oil)
Boiler
- Grate area
- 6.206 m²
- Firebox surface
- 26.106 m²
- Tube heating surface
- 247.68 m²
- Evaporative heating surface
- 273.786 m²
- Superheater surface
- 78.968 m²
- Total heating surface
- 352.8 m²
Power plant
- Driver diameter
- 1,854 mm
- Boiler pressure
- 17.2 bar
- Expansion type
- simple expansion
- Cylinders
- two, 572 x 711 mm
Power
- Power source
- steam
- Estimated power
- 2,461 kW (3,346 PS)
- Starting effort
- 183.5 kN
Calculated values
- Factor of adhesion
- 1 : 4.12
- Optimal speed
- 82 km/h
- Power-to-weight ratio
- 18.6 kW/t
- Heating Surface Equivalent
- 562.3 m²
- Cylinder volume/HSE
- 1 : 648.95
- Adhesive weight/Total
- 1 : 1.72
- Tractive force/Heating surface
- 1 : 10.87
- Grate area/Heating surface
- 1 : 56.84
- Firebox/Tube surface
- 1 : 9.49
- Total/Superheater
- 1 : 3.47
