Peninsular 2-6-2 "Prairie" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 6 (Locobase 12914)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 28, p. 229 and Vol 29, p. 288. Works numbers were 27312 in January 1906 and 30606 in April 1907.

Simpson Logging operated the Peninsular Railway, which eventually ran over 50 miles (80 km) of track up into Chehalis County (now Grays Harbor County).

In February 1936, broker Kern & Kibbee sold the 6 to Guy F Atkinson, a California contractor. The 7, which bore the name "Sol Simpson" when it was delivered was sold in April 1917 to the Alaska Railroad as their 21.

Specifications by Steve Llanso of Sweat House Media
Locobase ID12914
Number in Class2
Road Numbers6-7
Number Built2
BuilderBurnham, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase8'
Engine Wheelbase24.42'
Ratio of driving wheelbase to overall engine wheebase 0.33
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)
Weight on Drivers73000 lbs
Engine Weight98000 lbs
Tender Light Weight55000 lbs
Total Engine and Tender Weight153000 lbs
Tender Water Capacity2500 gals
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated)41 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter46"
Boiler Pressure160 psi
Cylinders (dia x stroke)16" x 24"
Tractive Effort18165 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.02
Heating Ability
Firebox Area107 sq. ft
Grate Area16 sq. ft
Evaporative Heating Surface1410 sq. ft
Superheating Surface
Combined Heating Surface1410 sq. ft
Evaporative Heating Surface/Cylinder Volume252.46
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2560
Same as above plus superheater percentage2560
Same as above but substitute firebox area for grate area17120
Power L14272
Power MT387.05


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