Denver & Rio Grande Western 2-6-6-2 Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class L-62 (Locobase 294)

Data from Wiener (1930); another source has the grate area as 63.4 sq ft, but a 3rd source (Bruce, 1952) agrees with Wiener and this is borne out by the D&RGW 1956 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

Eight Mallet compounds for helper service in Soldier Pass and Tennessee Pass. They were delivered as saturated-steam locomotives with a total of 395 2" tubes and a firebox whose heating surface included 40 sq ft of combustion chamber. Total EHS was 4,114 sq ft. As shown in the specs, however, they were later superheated. Unlike most such conversions, this class retained virtually all of the heating surface area of the saturated boiler.

Later renumbered 3300-3307. Retired in 1947-1952.

Class L-76 (Locobase 1466)

These two Mallet compounds were bought from the Norfolk & Western by the Denver & Rio Grande Western in 1947 to beef up helper service Retired in 1952 and 1950, respectively.

Data from 1952 D & RGW locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

Specifications by Steve Llanso of Sweat House Media
Locobase ID294 1466
RailroadDenver & Rio Grande Western (D&RGW)Denver & Rio Grande Western (D&RGW)
Number in Class82
Road Numbers3300-33073350-3351
Number Built8
Valve GearWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase30.33'10'
Engine Wheelbase46.33'48.83'
Ratio of driving wheelbase to overall engine wheebase 0.65 0.20
Overall Wheelbase (engine & tender)74.50'90.77'
Axle Loading (Maximum Weight per Axle)51600 lbs62600 lbs
Weight on Drivers295500 lbs364500 lbs
Engine Weight640000 lbs427000 lbs
Tender Light Weight159000 lbs286533 lbs
Total Engine and Tender Weight799000 lbs713533 lbs
Tender Water Capacity8000 gals16000 gals
Tender Fuel Capacity (oil/coal)12 tons23 tons
Minimum weight of rail (calculated)82 lb/yard101 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter57"57"
Boiler Pressure210 psi225 psi
High Pressure Cylinders (dia x stroke)20.5" x 32"22" x 32"
Low Pressure Cylinders (dia x stroke)33" x 32" (2)35" x 32" (2)
Tractive Effort60774 lbs74498 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.86 4.89
Heating Ability
Firebox Area250 sq. ft391 sq. ft
Grate Area54.40 sq. ft72.20 sq. ft
Evaporative Heating Surface3449 sq. ft4629 sq. ft
Superheating Surface657 sq. ft971 sq. ft
Combined Heating Surface4106 sq. ft5600 sq. ft
Evaporative Heating Surface/Cylinder Volume282.14328.79
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1142416245
Same as above plus superheater percentage1325219007
Same as above but substitute firebox area for grate area60900102931
Power L166839192
Power MT299.16333.58


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