Baltimore & Ohio Other Articulated Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class KL-1 (Locobase 13790)

Data from DeGolyer, Volume 38, p. 161. (Thanks to Chris Hohl for supplying the road number.)

In 1911, the B & O ordered a special 2-6-8-0 by mating one of its E-24 Consolidations (Locobase 4786) to a new front boiler and engine set that contained a feedwater heater with 369 2" tubes of much shorter length (8 feet 3 inches) and a total heating service area of 1,594 sq ft. The LP cylinders under this boiler section had 34" diameters.

The same problems with slipping and uneven traction encountered by other users of the 2-6-8-0 arrangement led to no other such engines and the KL-1 was converted back to a 2-8-0 in 1917.

Class LL-1 (Locobase 9617)

Data from B & O to 1954 Asstd Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. Works numbers were 49212-49216, 49699-49703 in March 1911; 50442-50451 in January 1912; 53748-53757 in August 1913.

A two-batch class of pushers that varied primarily in their weights. The first batch -- 7020-7039 -- put 461,000 lb on the rail while the last 10 weighed 5 tons more. Delivered with slide valves actuated by Walschaert gear feeding the low-pressure cylinders, the engines later received piston valves on those big cans; these were actuated by Baker gear.

According to Drury (1993), these big engines proved "slow and complicated". Still many served throughout World War Two before being scrapped in 1949-1950. Several were rebuilt as EL-4 class 2-8-8-0s.

Class O/DD1 (Locobase 2794)

Data validated by table from July 1904 AERJ. Works number was 27478 in May 1904.

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 by Steve Llanso of Sweat House Media
Locobase ID13790 9617 2794
RailroadBaltimore & Ohio (B&O)Baltimore & Ohio (B&O)Baltimore & Ohio (B&O)
Number in Class1301
Road Numbers24212401-2420, 2422-2431/7020-70492400/7000
Number Built1301
Valve GearWalschaertWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase18.96'15'10'
Engine Wheelbase45.37'40.67'30.67'
Ratio of driving wheelbase to overall engine wheebase 0.42 0.37 0.33
Overall Wheelbase (engine & tender)77.23'64.58'
Axle Loading (Maximum Weight per Axle)50800 lbs63400 lbs
Weight on Drivers309800 lbs471900 lbs334565 lbs
Engine Weight326850 lbs471900 lbs334565 lbs
Tender Light Weight143370 lbs196000 lbs206400 lbs
Total Engine and Tender Weight470220 lbs667900 lbs540965 lbs
Tender Water Capacity7000 gals12000 gals7000 gals
Tender Fuel Capacity (oil/coal)15 tons12.5 tons15 tons
Minimum weight of rail (calculated)74 lb/yard98 lb/yard93 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter56"56"56"
Boiler Pressure205 psi210 psi235 psi
High Pressure Cylinders (dia x stroke)22" x 28"26" x 32"20" x 32"
Low Pressure Cylinders (dia x stroke)34" x 28" (2)41" x 32" (2)32" x 32" (2)
Tractive Effort59447 lbs98352 lbs65664 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.21 4.80 5.10
Heating Ability
Firebox Area184.35 sq. ft321.50 sq. ft219 sq. ft
Grate Area49 sq. ft100 sq. ft72.20 sq. ft
Evaporative Heating Surface2847 sq. ft5641 sq. ft5585 sq. ft
Superheating Surface1002 sq. ft
Combined Heating Surface2847 sq. ft6643 sq. ft5585 sq. ft
Evaporative Heating Surface/Cylinder Volume231.10286.87480.00
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation100452100016967
Same as above plus superheater percentage100452415016967
Same as above but substitute firebox area for grate area377927764251465
Power L1245165204919
Power MT122.09243.68194.48


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