The reference for locomotives and railcars
Mexican State Railway class NR-1
Mexico | 1937 | 10 produced
No. 2708 in January 1960 in Puebla
No. 2708 in January 1960 in Puebla
Stan Kistler / collection Taylor Rush

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.

Axle config4-6-4 (Hudson) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase37 ft 9 in
Fixed wheelbase13 ft
Total wheelbase69 ft 1 in
Service weight292,000 lbs
Adhesive weight170,000 lbs
Total weight465,660 lbs
Axle load56,670 lbs
Water capacity8,500 us gal
Fuel capacity4,037 us gal (oil)
Power sourcesteam
Estimated power3,300 hp (2,461 kW)
Optimal speed51 mph
Starting effort41,263 lbf
Power Plant
Driver diameter73 in
Boiler pressure250 psi
Expansion typesimple
Cylinderstwo, 22 1/2 x 28 in
Grate area66.8 sq ft
Firebox area281 sq ft
Tube heating area2,666 sq ft
Evaporative heating area2,947 sq ft
Superheater area850 sq ft
Total heating area3,797 sq ft
Calculated Values
steam locomotive
last changed: 03/2023

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