Virginian class AE
The Virginian Class AE was a greater success than the Santa Fe class 3000 that was also built ten times a few years later. It was about 70,000 pounds heavier and was built as a Mallet locomotive from the start. To avoid the problems of an overly long boiler, the boiler was designed with the largest possible diameter and moderate length to get better proportions. With a diameter of almost ten feet, it is considered the widest locomotive boiler of all time. The low-pressure cylinders also set new standards with a diameter of 48 inches and a volume of nearly 58.000 cubic inches or 950 liters each.
At just over 135.000 pounds, the normal starting tractive effort in compound mode already reached a very impressive value. Like many Mallet locomotives, the AE also had a special starting valve that made it possible to direct the live steam into the low-pressure cylinders for starting. This resulted in a starting tractive effort of 162.000 pounds using the usual calculation method used in Anglo-American countries.
Due to the dimensions of the locomotives, it was necessary to deliver them without a cab and low-pressure cylinders and only to assemble them at their destination, where operation of the locomotives without colliding with obstacles on the track was guaranteed. A relatively short tender was selected so that existing turntables could also be used. Although these locomotives also had to struggle with steam production as the speed increased, they are considered to be more successful than the ATSF 3000. They were mostly used as pusher locomotives for heavy coal trains, which often only moved at around 8 mph on the ramps and did not overload the boiler of the AE. There are also reports of locomotives hauling trains weighing over 17,000 tons without assistance. They remained in service for almost 30 years and were eventually replaced on the steepest inclines by electric locomotives.
Technical data
General
- Built
- 1918
- Manufacturers
- ALCO
- Wheel arrangement
- 2-10-10-2
- Gauge
- 1,435 mm (Standard gauge)
Dimensions and weights
- Wheelbase
- 19.58 m
- Total wheelbase
- 29.57 m
- Service mass
- 310.3 t
- Adhesion mass
- 279.9 t
- Total mass
- 407.5 t
- Rigid wheelbase
- 6.05 m
- Axle load
- 28 t
- Water capacity
- 49,210 l
- Fuel capacity
- 10.9 t (coal)
Boiler
- Grate area
- 10.108 m²
- Firebox surface
- 47.938 m²
- Tube heating surface
- 751.493 m²
- Evaporative heating surface
- 799.431 m²
- Superheater surface
- 196.955 m²
- Total heating surface
- 996.4 m²
Power plant
- Driver diameter
- 1,422 mm
- Boiler pressure
- 14.8 bar
- Expansion type
- compound
- Cylinders
- four, HP: 762 x 813 mm and LP: 1,219 x 813 mm
Power
- Power source
- steam
- Estimated power
- 2,610 kW (3,549 PS)
- Starting effort
- 601.3 kN
- Starting effort simple
- 721.5 kN
Calculated values
- Factor of adhesion
- 1 : 4.57
- Optimal speed
- 27 km/h
- Power-to-weight ratio
- 8.4 kW/t
- Heating Surface Equivalent
- 1,433.0 m²
- Cylinder volume/HSE
- 1 : 1,179.49
- Adhesive weight/Total
- 1 : 1.11
- Tractive force/Heating surface
- 1 : 12.60
- Grate area/Heating surface
- 1 : 98.57
- Firebox/Tube surface
- 1 : 15.68
- Total/Superheater
- 1 : 4.06