Like the Erie's Triplex 2-8-8-8-2s, this single locomotive showed all the limitations of trying to cram so much tractive power under one boiler.
Although this design had slightly smaller cylinders under a slightly larger boiler, the grate and evaporative heating surface were still too small. The small firebox gained some additional direct heating surface from the 72 sq ft (6.7 sq m) in five arch tubes supporting the brick arch. A Gaines type combustion chamber was located ahead of the half-height Gaines wall in the firebox (For a full description of the Gaines combustion chamber's intended effect on combustion, see Locobase 4228.) The firebox's high fuel demand was fed through a Street stoker.
Baldwin feed water heater contained 437 sq ft (40.6 sq m). All six cylinders admitted steam through 14-inch (356 mm) piston valves.
The specifications included the requirement that the engine drag 2,580 tons (2,345 metric tonnes) of cars and leading from Elmore to Clark's Gap over 14 miles (22.5 km) of track of which 12 miles (19.3 km) ascended at 2.07% and wound around ten 12-degree curves. Four-fifths of the load (2,064 tons or 1,876 metric tonnes) were to go up the grade at 10 mph (16 km/h).
Drury (1993) notes that compared to the Erie engines, the 700 "was slower and ran out of steam faster[!]..." He adds that one tunnel had only four inches of clearance, which must have made a passage hell on earth for the locomotive and its crew. "It never made a successful trip," according to Drury.
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Number in Class||1|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||15.25 / 4.65|
|Engine Wheelbase (ft / m)||67.58 / 20.60|
|Ratio of driving wheelbase to overall engine wheebase||0.23|
|Overall Wheelbase (engine & tender) (ft / m)||91.25 / 27.81|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)||62,000 / 28,123|
|Weight on Drivers (lbs / kg)||725,475 / 329,070|
|Engine Weight (lbs / kg)||842,310 / 382,066|
|Tender Loaded Weight (lbs / kg)|
|Total Engine and Tender Weight (lbs / kg)||842,310|
|Tender Water Capacity (gals / ML)||13,000 / 49.24|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||12 / 90.90|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||101 / 50.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||56 / 1422|
|Boiler Pressure (psi / kPa)||222 / 15.30|
|High Pressure Cylinders (dia x stroke) (in / mm)||34" x 32" / 864x813|
|Low Pressure Cylinders (dia x stroke) (in / mm)||34" x 32" / 864x813 (4)|
|Tractive Effort (lbs / kg)||186,975 / 84810.53|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.88|
|Firebox Area (sq ft / m2)||431 / 40.04|
|Grate Area (sq ft / m2)||107.60 / 10|
|Evaporative Heating Surface (sq ft / m2)||8120 / 754.37|
|Superheating Surface (sq ft / m2)||2059 / 191.29|
|Combined Heating Surface (sq ft / m2)||10,179 / 945.66|
|Evaporative Heating Surface/Cylinder Volume||241.47|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||23,887|
|Same as above plus superheater percentage||28,665|
|Same as above but substitute firebox area for grate area||114,818|