Data from M&PA 1956ca Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volumes 29, p. 209 and 35, pp. 296+. Works numbers were 29760 in December 1906 and 34945 in July 1910.
The Ma and Pa ordered these two Ten-wheelers almost four years apart. Specifications described a profile that included 2 1/2% grades and 25-degree curves. All of the specs for the 28 repeated those for the 27 to the last jot and tittle--even the details about how the tubes were to be swaged down to 2" diameter.
Both were retired in 1955, the 28 first in August and the 27 in December.
Principal Dimensions by Steve Llanso of Middle Run Media | |
---|---|
Class | 27 |
Locobase ID | 7052 |
Railroad | Maryland & Pennsylvania (Ma & Pa) |
Country | USA |
Whyte | 4-6-0 |
Number in Class | 2 |
Road Numbers | 27-28 |
Gauge | Std |
Number Built | 2 |
Builder | Burnham, Williams & Co |
Year | 1906 |
Valve Gear | Stephenson |
Locomotive Length and Weight | |
Driver Wheelbase (ft / m) | 12 / 3.66 |
Engine Wheelbase (ft / m) | 23.04 / 7.02 |
Ratio of driving wheelbase to overall engine wheelbase | 0.52 |
Overall Wheelbase (engine & tender) (ft / m) | 50.42 / 15.37 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
Weight on Drivers (lbs / kg) | 102,960 / 46,702 |
Engine Weight (lbs / kg) | 128,860 / 58,450 |
Tender Loaded Weight (lbs / kg) | 79,773 / 36,184 |
Total Engine and Tender Weight (lbs / kg) | 208,633 / 94,634 |
Tender Water Capacity (gals / ML) | 4000 / 15.15 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 6 / 6 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 57 / 28.50 |
Geometry Relating to Tractive Effort | |
Driver Diameter (in / mm) | 56 / 1422 |
Boiler Pressure (psi / kPa) | 180 / 1240 |
High Pressure Cylinders (dia x stroke) (in / mm) | 19" x 24" / 483x610 |
Tractive Effort (lbs / kg) | 23,671 / 10737.00 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.35 |
Heating Ability | |
Tubes (number - dia) (in / mm) | 228 - 2.25" / 57 |
Flues (number - dia) (in / mm) | |
Flue/Tube length (ft / m) | 13.25 / 4.04 |
Firebox Area (sq ft / m2) | 152 / 14.13 |
Grate Area (sq ft / m2) | 25 / 2.32 |
Evaporative Heating Surface (sq ft / m2) | 1920 / 178.44 |
Superheating Surface (sq ft / m2) | |
Combined Heating Surface (sq ft / m2) | 1920 / 178.44 |
Evaporative Heating Surface/Cylinder Volume | 243.65 |
Computations Relating to Power Output (More Information) | |
Robert LeMassena's Power Computation | 4500 |
Same as above plus superheater percentage | 4500 |
Same as above but substitute firebox area for grate area | 27,360 |
Power L1 | 5714 |
Power MT | 367.05 |