US Railroad Administration 0-6-0
The lightest of the USRA standard locomotives was a light switcher by US standards with three coupled axles and no carrying axles. With an axle load of 55.000 pounds, it still reached a weight that was to be found at the same time on ten-coupled freight locomotives in Central Europe. Like all USRA types, it was operated with superheated steam and, thanks to a driving wheel diameter of 51 inches and correspondingly large cylinders, achieved a starting tractive effort of almost 40,000 pounds or 175 kN.
A total of 255 of the actual USRA design were manufactured by ALCO in 1918 and 1919. Most customers procured between five and ten locomotives. The three largest operators were the Baltimore & Ohio with 40 class D-30, the Chicago & North Western with 35 class M-3 and the Pennsylvania Railroad with 30 class B28. Later, some railroads ordered more copies of the original USRA design. The Wheeling & Lake Erie only procured vehicles, of which two still exist today. While number 3984 is already being restored, number 3960 is still awaiting the start of its restoration.
Technical data
General
- Built
- 1918-1919
- Manufacturers
- ALCO
- Wheel arrangement
- 0-6-0 (Six-coupled)
- Gauge
- 1,435 mm (Standard gauge)
Dimensions and weights
- Length
- 19.15 m
- Wheelbase
- 3.35 m
- Total wheelbase
- 14.90 m
- Service mass
- 74.8 t
- Adhesion mass
- 74.8 t
- Total mass
- 140.2 t
- Rigid wheelbase
- 3.35 m
- Axle load
- 24.9 t
- Water capacity
- 30,283 l
- Fuel capacity
- 14.5 t (coal)
Boiler
- Grate area
- 3.066 m²
- Firebox surface
- 12.821 m²
- Tube heating surface
- 162.395 m²
- Evaporative heating surface
- 175.215 m²
- Superheater surface
- 47.845 m²
- Total heating surface
- 223.1 m²
Power plant
- Driver diameter
- 1,295 mm
- Boiler pressure
- 13.1 bar
- Expansion type
- simple expansion
- Cylinders
- two, 533 x 711 mm
Power
- Power source
- steam
- Estimated power
- 895 kW (1,217 PS)
- Starting effort
- 173.9 kN
Calculated values
- Factor of adhesion
- 1 : 4.22
- Optimal speed
- 32 km/h
- Power-to-weight ratio
- 12.0 kW/t
- Heating Surface Equivalent
- 335.0 m²
- Cylinder volume/HSE
- 1 : 948.76
- Adhesive weight/Total
- 1 : 1.00
- Tractive force/Heating surface
- 1 : 16.29
- Grate area/Heating surface
- 1 : 72.75
- Firebox/Tube surface
- 1 : 12.67
- Total/Superheater
- 1 : 3.66