Boston & Maine Other Articulated Locomotives

Class M-2-a (Locobase 6942)

Data from B&G - UCCO Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection, from the Utah Rails site http://utahrails.net/bingham/kcc-steam.php and http://utahrails.net/bingham/bingham-1900-1914.php, accessed 1 July 2005, and from Drury (1993).

The firebox heating surface includes 5 arch tubes of 60 sq ft. Builder's work numbers were 63455-63456. 801 had 5 fewer tubes, which resulted in a total evaporative heating surface of 5,147 sq ft.

In the east, about the only job for which these big all-adhesion Mallets were suited was yard switching and that's what the B & M wanted them to do. After 7 years of work at the Mechanicville hump yard, however, the B & M sold them to the Bingham & Garfield copper mining road in Utah.

Specifications
ClassM-2-a
Locobase ID6942
RailroadBoston & Maine (B & M)
Whyte0-8-8-0
Road Numbers800-801
GaugeStd
BuilderAlco-Schenectady
Year1922
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase14.75'
Engine Wheelbase40.29'
Ratio of driving wheelbase to overall engine wheebase 0.37
Overall Wheelbase (engine & tender)79'
Axle Loading (Maximum Weight per Axle)0
Weight on Drivers474100 lbs
Engine Weight474100 lbs
Tender Light Weight219100 lbs
Total Engine and Tender Weight693200 lbs
Tender Water Capacity12000 gals
Tender Fuel Capacity (oil/coal)19 tons
Minimum weight per yard of rail on which locomotive could run99 lb rail
Geometry Relating to Tractive Effort
Driver Diameter51"
Boiler Pressure250 psi
Cylinders (dia x stroke)26" x 28"
Low Pressure Cylinders (dia x stroke)40" x 28"
Tractive Effort110885 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.28
Heating Ability
Firebox Area375 sq. ft
Grate Area77 sq. ft
Evaporative Heating Surface5215
Superheating Surface1850
Combined Heating Surface7065
Evaporative Heating Surface/Cylinder Volume303.09
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation19250
Same as above plus superheater percentage24255
Same as above but substitute firebox area for grate area118125
Power L112388
Power MT460.85

Credits

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