Montour 2-8-2 "Mikado" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 20 (Locobase 28)

Data from table in May 1916 issue of Railway Mechanical Engineer (RME). See also Bob Ciminel, "Paid by the Pound", Montour Trail-Letter, Volume 20, No 1 (January-February 2009), p.6. (Many thanks to Chris Hohl for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error .)

The Montour was a coal-and-steel shortline in western Pennsylvania, a hilly profile with tunnels and curves where this low-drivered Mike fit right in. Bob Ciminel says the Brooks order resulted from the opening of the Mifflin Extension, whose steeper grades demanded more power in the motive power. Ciminel explains his title by walking the reader throught the pay scales of the time, which were built through an agreement with the BLE upon the amount of adhesive weight under the engineer's throttle hand.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID28
Number in Class16
Road Numbers20-35
Number Built16
Valve GearBaker
Locomotive Length and Weight
Driver Wheelbase (ft / m)16.50 / 5.03
Engine Wheelbase (ft / m)35.33 / 10.77
Ratio of driving wheelbase to overall engine wheelbase 0.47
Overall Wheelbase (engine & tender) (ft / m)63.50 / 19.35
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)249,500 / 113,171
Engine Weight (lbs / kg)296,500 / 134,490
Tender Loaded Weight (lbs / kg)164,200 / 74,480
Total Engine and Tender Weight (lbs / kg)460,700 / 208,970
Tender Water Capacity (gals / ML)9000 / 34.09
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)12 / 11
Minimum weight of rail (calculated) (lb/yd / kg/m)104 / 52
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)57 / 1448
Boiler Pressure (psi / kPa)185 / 12.80
High Pressure Cylinders (dia x stroke) (in / mm)27" x 32" / 686x813
Tractive Effort (lbs / kg)64,357 / 29191.88
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.88
Heating Ability
Tubes (number - dia) (in / mm)312 - 2" / 51
Flues (number - dia) (in / mm)45 - 5.375" / 137
Flue/Tube length (ft / m)16 / 4.88
Firebox Area (sq ft / m2)286 / 26.57
Grate Area (sq ft / m2)66.70 / 6.20
Evaporative Heating Surface (sq ft / m2)3892 / 361.71
Superheating Surface (sq ft / m2)836 / 77.70
Combined Heating Surface (sq ft / m2)4728 / 439.41
Evaporative Heating Surface/Cylinder Volume183.50
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation12,340
Same as above plus superheater percentage14,561
Same as above but substitute firebox area for grate area62,434
Power L110,644
Power MT376.21

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Wes Barris