Baltimore & Ohio Other Articulated Locomotives

Class DD1 (Locobase 2794)

Data validated by table from July 1904 AERJ.

The first standard-gauge Mallet built in the United States, this helper engine was jointly designed by the B&O's James E Muhlfield and Alco's Carl J. Mellin. Old Maud, so called after a comic-strip mule, proved an immediate success on the B&O's western Pennsylvania grades. Her scrapping came only in 1938.

Specifications
ClassDD1
Locobase ID2794
RailroadBaltimore & Ohio (B&O)
Whyte0-6-6-0
Road Numbers2400
GaugeStd
BuilderAlco-Schenectady
Year1904
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase10'
Engine Wheelbase30.67'
Ratio of driving wheelbase to overall engine wheebase 0.33
Overall Wheelbase (engine & tender)64.58'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers334565 lbs
Engine Weight334565 lbs
Tender Light Weight206400 lbs
Total Engine and Tender Weight540965 lbs
Tender Water Capacity7000 gals
Tender Fuel Capacity (oil/coal)15 tons
Minimum weight per yard of rail on which locomotive could run92.93 lb rail
Geometry Relating to Tractive Effort
Driver Diameter56"
Boiler Pressure235 psi
Cylinders (dia x stroke)20" x 32"
Low Pressure Cylinders (dia x stroke)32" x 32"
Tractive Effort65664 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.10
Heating Ability
Firebox Area219 sq. ft
Grate Area72.20 sq. ft
Evaporative Heating Surface5585
Superheating Surface
Combined Heating Surface5585
Evaporative Heating Surface/Cylinder Volume480.00
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation16967
Same as above plus superheater percentage16967
Same as above but substitute firebox area for grate area51465
Power L14918.75
Power MT194.47

Reference

Credits

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