Keystone Mills 2-6-0 "Mogul" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 15 (Locobase 13898)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University , Volume 41, p. 37. Works number was 38470 in October 1912.

Although based on a widely used plantation Mogul often operated on the metre gauge or larger, the 15 had to be adapted to the narrower spread of the 3-foot layout used by this Waukegon, Texas logger for its tram road. This meant a narrower, hence smaller grate, but deeper firebox that could burn either coal or wood; its heating surface area was slightly larger as a result.

The specs say emphatically that the "old" rail weight is 35 lb/yard (17.5 kg/metre) and that the "weight of engine must not overrun specification. Investigate weight and if specified weight is too great for 35 lb. rails, it must be reduced." Note that because it was a logging road and not a common carrier, the KMC could specify the dangerously antiquated link-and-pin couplers that had been banned from common carriers for decades.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID13898
RailroadKeystone Mills
Number in Class1
Road Numbers15
Number Built1
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 9.67 / 2.95
Engine Wheelbase (ft / m)15.92 / 4.85
Ratio of driving wheelbase to overall engine wheelbase 0.61
Overall Wheelbase (engine & tender) (ft / m)35.58 / 10.84
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)49,000 / 22,226
Engine Weight (lbs / kg)58,000 / 26,308
Tender Loaded Weight (lbs / kg)44,000 / 19,958
Total Engine and Tender Weight (lbs / kg)102,000 / 46,266
Tender Water Capacity (gals / ML)2200 / 8.33
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)27 / 13.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)42 / 1067
Boiler Pressure (psi / kPa)160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)14" x 18" / 356x457
Tractive Effort (lbs / kg)11,424 / 5181.85
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.29
Heating Ability
Tubes (number - dia) (in / mm)153 - 1.75" / 44
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m) 8.62 / 2.63
Firebox Area (sq ft / m2)71 / 6.60
Grate Area (sq ft / m2)12.50 / 1.16
Evaporative Heating Surface (sq ft / m2)669 / 62.15
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)669 / 62.15
Evaporative Heating Surface/Cylinder Volume208.41
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2000
Same as above plus superheater percentage2000
Same as above but substitute firebox area for grate area11,360
Power L13573
Power MT482.27

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Wes Barris