Firebox heating surface in the specifications included 78.5 sq ft (7.29 sq m) of arch tubes that were later removed.
These were far better proportioned engines than the Triplexes built for the Erie or the 2-8-8-8-4 that later entered service on the Virginian. Their boiler and grate demand factors were within reason, which meant the crew could keep steam up, especially since the class used a Duplex or Standard mechanical stoker. The HP cylinders were supplied steam through 16" (406 mm) piston valves, while the massive LP cylinders, which contained a volume of 33.51 cu ft (949 liters) each, used double-ported slide valves. Simple starting TE reached 176,000 lb (79,832 kg.or 782.8 kN).
Chris Hohl notes that the original tenders held 12,000 US gallons of water (45,420 litres). Each loaded tender weighed 214,300 lb (97,205 kg).
Estimating Engineer James Partington of Alco delivered a paper in December 1921 in which he described the pulling power of one of these double decapods. One pulled a 15,725-ton (14,295 tonne) train from Princeton, Va. to Roanoke burning 26.9 lb of coal per 1,000 ton-miles (18.37 kg per 1,000 km). Another 2-10-10-2 managed 110 cars or 17,250 tons (15,680 tonnes) over a ruling adverse grade of 0.2%.
They performed well for 30 years, first as pushers for the 2.11% grade at Elmore until replaced by electric engines, later as helpers on other grades. EW King, Jr (in Drury, 1993) notes that except for the addition of Worthington BL feedwater heaters, these engines were never modified.
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Number in Class||10|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||19.83 / 6.04|
|Engine Wheelbase (ft / m)||64.25 / 19.58|
|Ratio of driving wheelbase to overall engine wheebase||0.31|
|Overall Wheelbase (engine & tender) (ft / m)||97 / 29.57|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)||61,712 / 27,992|
|Weight on Drivers (lbs / kg)||617,000 / 279,867|
|Engine Weight (lbs / kg)||684,000 / 310,258|
|Tender Loaded Weight (lbs / kg)||231,000|
|Total Engine and Tender Weight (lbs / kg)||915,000|
|Tender Water Capacity (gals / ML)||13,000 / 49.24|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||20 / 18.20|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||103 / 51.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||56 / 1422|
|Boiler Pressure (psi / kPa)||215 / 14.80|
|High Pressure Cylinders (dia x stroke) (in / mm)||30" x 32" / 762x813|
|Low Pressure Cylinders (dia x stroke) (in / mm)||48" x 32" / x813|
|Tractive Effort (lbs / kg)||135,170 / 61312.15|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.56|
|Firebox Area (sq ft / m2)||516 / 47.96|
|Grate Area (sq ft / m2)||108.80 / 10.11|
|Evaporative Heating Surface (sq ft / m2)||8605 / 799.72|
|Superheating Surface (sq ft / m2)||2120 / 197.03|
|Combined Heating Surface (sq ft / m2)||10,725 / 996.75|
|Evaporative Heating Surface/Cylinder Volume||328.69|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||23,392|
|Same as above plus superheater percentage||28,070|
|Same as above but substitute firebox area for grate area||133,128|