Canadian Pacific Other Articulated Locomotives

Class R1 (Locobase 3570)

Data from Railway Age Gazette, 12 July 1912, pp. 50-53.

The single simple-expansion Angus supplied to the CP as a helper engine over the 2.2% grade in the Canadian Rockies. A curious feature of this locomotive was the centered position of its 4 cylinders. All four cylinders were cast to the same design with inboard valves and outboard cylinders. The front driver set preceded its cylinders, the rear driving set trailed its pair.

Obviously the goal of 50-mph operation was never achieved with this all-adhesion articulated. Like its compound brothers (Locobase 3569), this engine became a 2-10-0 Decapod in 1917.

Class R1 - compound (Locobase 3569)

Data from Wiener (1930).

Designed for helper service over the passes of the Canadian Rockies, these were very unusual Mallets for a variety of reasons. They were the only articulateds ever operated by a Canadian railroad and they had the two cylinder sets centered under the boiler. As seen in profile, the front driver set led, then its pair of LP cylinder, then the HP cylinders and finally the driver set they drove. As Wiener (1930) points out, this reduced steam pipe length, a reasonable goal especially for compounds.

The boiler had a vertical superheater whose elements intercepted the flow of gas from the boiler to the feedwater heater forward. Externally, this showed as a box on the boiler over the front cylinder set.

Although these can't be seen as failures, the CP decided on rigid-wheelbase locomotives of greater power (culminating in the 2-10-4 Selkirks) and this 5-engine class (and one more simple-expansion variant, which see at Locobase 3570) were converted to 2-10-0 Decapods in 1917. (See Locobase 4529).

Specifications
ClassR1R1 - compound
Locobase ID35703569
RailroadCanadian PacificCanadian Pacific
Whyte0-6-6-00-6-6-0
Road Numbers57555750-5754
GaugeStdStd
BuilderAngus WorksAngus Works
Year19091909
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase10.33'10.33'
Engine Wheelbase35.17'35.17'
Ratio of driving wheelbase to overall engine wheebase 0.29 0.29
Overall Wheelbase (engine & tender)60.80'60.80'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers262000 lbs262000 lbs
Engine Weight262000 lbs262000 lbs
Tender Light Weight133000 lbs133000 lbs
Total Engine and Tender Weight395000 lbs395000 lbs
Tender Water Capacity5900 gals5900 gals
Tender Fuel Capacity (oil/coal)13.4 tons13.4 tons
Minimum weight per yard of rail on which locomotive could run72.78 lb rail72.78 lb rail
Geometry Relating to Tractive Effort
Driver Diameter58"58"
Boiler Pressure200 psi200 psi
Cylinders (dia x stroke)20" x 26" (4)23.25" x 26"
Low Pressure Cylinders (dia x stroke)" x "34" x 26"
Tractive Effort60966 lbs56138 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.30 4.67
Heating Ability
Firebox Area185 sq. ft185 sq. ft
Grate Area59 sq. ft59 sq. ft
Evaporative Heating Surface29502950
Superheating Surface548548
Combined Heating Surface34983498
Evaporative Heating Surface/Cylinder Volume156.02230.90
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1180011800
Same as above plus superheater percentage13648.6013648.60
Same as above but substitute firebox area for grate area42796.4642796.46
Power L19005.246232.00
Power MT454.65314.64

Reference

Credits

Introduction and specifications provided by Steve Llanso of Sweat House Media.