Baltimore & Ohio 0-8-0 "Switcher" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class Dragon (Locobase 1022)

Data from Zerah Colburn, The Locomotive Engine (1851) and Joseph Snowden Bell, The Early Motive Power of the Baltimore & Ohio (1912) . See also Snowden Bell's long article in the October 1922 Railway and Locomotive Engineering, pp. 277-280. Works number was 325.

First of six Baldwin-built freight locomotives with inclined cylinders and a "flexible-beam" truck that allowed the engine to negotiate tighter curves. This was a parallelogram arrangement that let one pair of drivers (usually the front axle) move right while the next pair (the second axle) simultaneously slid left (e.g.); the 3rd and 4th axles were fixed in the frame.

Two other locomotives (Memnon & Saturn) were built by Newcastle Mfg and 3 -- Hero, Giant, & Lion -- by the B&O itself. Bell's recollection of these engines as of 1857 was that they did not use flexible-beam trucks.


Class Eight-wheel freight (Locobase 8808)

Data from Zerah Colburn, The Locomotive Engine (1851) and Joseph Snowden Bell, The Early Motive Power of the Baltimore & Ohio (1912) .

Three of the class - 67, 72, & 83 - had 20" diameter cylinders, but were otherwise identical. These were the last large class of 0-8-0s supplied to the B & O.


Class Saturn (Locobase 8807)

Data from Zerah Colburn, The Locomotive Engine (1851) and Joseph Snowden Bell, The Early Motive Power of the Baltimore & Ohio (1912) .

This class followed Baldwin's flexible-beam "Dragon", but apparently did not have the parallelogram arrangement themselves. Two locomotives (Memnon & Saturn) were built by New Castle Manufacturing in New Castle, Del and 3 -- Hero, Giant, & Lion -- by the B&O itself.


Class Susquehanna (Locobase 2552)

See White (1968) for an extensive discussion of Ross Winans' Camel design. A constant thread is the novelty of many of his choices, all made to arrive at greater simplicity and ruggedness, according to Winans. But, White comments, "Against these claims of superiority came equally valid claims of clumsiness and inconvenience."

The camel design was among the oddest to be built in large (320) numbers. (An article in the December 1891 Railway Master Mechanic -- reprinted on http://www.railroadextra.com/abboc.html -- says 219 were produced from June 1848 to February 1857.)

A straight boiler of significant girth came ahead of a large, sloping firebox. The engineer's position was established on top of the boiler in a structure reminiscent of a howdah, the shooting blind often placed on elephants in India. The engineer shared the house with the tall steam dome which was positioned over the first driver set, just behind the odd stack, which had a pipe in front of the exhaust chimney to catch cinders.

The boiler was dangerously weakened by large holes for the steam dome and coal chutes, the firebox was large and encumbered by hoppers (to ensure coal got to the front of the grate), the drawbar connection was prone to failure, accessories like the feed-water pump were poorly placed, the cylinders weakly mounted, the valve motion complicated and difficult to keep aligned.

The camel's builder, says White, "is redeemed, in part, by the service performed by these unique machines." For their time, he notes, they could perform prodigies of slow-freight haulage. The 1891 article writer agreed, noting they could pull 160-ton freight trains up a grade of better than 2%.

Specifications by Steve Llanso of Sweat House Media
ClassDragonEight-wheel freightSaturnSusquehanna
Locobase ID1022 8808 8807 2552
RailroadBaltimore & Ohio (B&O)Baltimore & Ohio (B&O)Baltimore & Ohio (B&O)Baltimore & Ohio (B&O)
CountryUSAUSAUSAUSA
Whyte0-8-00-8-00-8-00-8-0
Number in Class1116
Road Numbers5133-4, 38, 40, 43, 49+54, 56-57, 63-64
GaugeStdStdStdStd
Number Built1116
BuilderM W BaldwinB& OseveralRoss Winans
Year1848185018481854
Valve Geardrop-hook
Locomotive Length and Weight
Driver Wheelbase (ft / m)11.25 / 3.4311.2511.25 / 3.43
Engine Wheelbase (ft / m)11.25 / 3.4311.25 / 9.4030.83 / 9.4011.25 / 9.40
Ratio of driving wheelbase to overall engine wheebase111
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)41,000 / 18,59757,400 / 26,03647,000 / 21,31954,000 / 24,494
Engine Weight (lbs / kg)41,000 / 18,59757,400 / 26,03647,000 / 21,31954,000 / 24,494
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)1900 / 7.20
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)5 / 4.50
Minimum weight of rail (calculated) (lb/yd / kg/m)17 / 8.5024 / 1220 / 1023 / 11.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)43 / 109243 / 109243 / 109243 / 1092
Boiler Pressure (psi / kPa)65 / 4.5065 / 4.5065 / 4.5090 / 6.20
High Pressure Cylinders (dia x stroke) (in / mm)14.5" x 18" / 368x45719" x 22" / 483x55917" x 22" / 432x55919" x 22" / 483x559
Tractive Effort (lbs / kg)4863 / 2205.8210,205 / 4628.928169 / 3705.4014,129 / 6408.81
Factor of Adhesion (Weight on Drivers/Tractive Effort) 8.43 5.62 5.75 3.82
Heating Ability
Firebox Area (sq ft / m2)87.50 / 8.1386
Grate Area (sq ft / m2)18 / 1.6710.80 / 123.50 / 2.18
Evaporative Heating Surface (sq ft / m2)1072 / 99.631000 / 92.941000 / 92.94
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1072 / 99.631000 / 92.941000 / 92.94
Evaporative Heating Surface/Cylinder Volume148.49173.02138.51
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation11707022115
Same as above plus superheater percentage11707022115
Same as above but substitute firebox area for grate area56887740
Power L19741278
Power MT149.64208.70

Reference