Mogiana 4-6-2 Locomotives in Brazil


Class Details by Steve Llanso of Sweat House Media

Class 260 (Locobase 20500)

Data from "Locomotives for the Brazilian Centennial Exhibition", Railway Age, Volume 74, No 8 (24 February 1923), pp. 467-468. Works numbers were 59126-59128 in March 1917, 62555-62556 in January 1921, 63464 in November 1922, and 65532-65533 in April 1924.

Alco's Pittsburgh Works produced the first three wood-burning Pacifics, which went to what was then the longest narrow-gauge private railway in South America. The design, which featured a relatively small grate but rather large piston valves (10" or 254 mm), was produced by Alco's Paterson, NJ subsidiary Cooke Locomotive Works for the Sorocbana in 1918 (Locobase ). Cooke then produced more of the same design for the Mogyana in the early 1920s.

It's likely as well that two more engines--268-269--repeated the same design in June 1926, but by then Cooke had been closed and Alco's remaining works at Schenectady finished the class.

Principal Dimensions by Steve Llanso of Sweat House Media

Class260
Locobase ID20500
RailroadMogiana
CountryBrazil
Whyte4-6-2
Number in Class8
Road Numbers260-267
GaugeMetre
Number Built8
BuilderAlco - multiple works
Year1917
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m) 9.50 / 2.90
Engine Wheelbase (ft / m)25.83 / 7.87
Ratio of driving wheelbase to overall engine wheelbase 0.37
Overall Wheelbase (engine & tender) (ft / m)49 / 14.94
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)71,000 / 32,205
Engine Weight (lbs / kg)113,000 / 51,256
Tender Loaded Weight (lbs / kg)68,600 / 31,116
Total Engine and Tender Weight (lbs / kg)181,600 / 82,372
Tender Water Capacity (gals / ML)2600 / 9.85
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 5.50 / 5
Minimum weight of rail (calculated) (lb/yd / kg/m)39 / 19.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)45 / 1143
Boiler Pressure (psi / kPa)170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)17.5" x 20" / 445x508
Tractive Effort (lbs / kg)19,668 / 8921.27
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.61
Heating Ability
Tubes (number - dia) (in / mm)103 - 2.008" / 51
Flues (number - dia) (in / mm)16 - 5.394" / 137
Flue/Tube length (ft / m)16 / 4.88
Firebox Area (sq ft / m2)94 / 8.73
Grate Area (sq ft / m2)29.40 / 2.73
Evaporative Heating Surface (sq ft / m2)1309 / 121.61
Superheating Surface (sq ft / m2)308 / 28.61
Combined Heating Surface (sq ft / m2)1617 / 150.22
Evaporative Heating Surface/Cylinder Volume235.10
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4998
Same as above plus superheater percentage5948
Same as above but substitute firebox area for grate area19,016
Power L110,422
Power MT970.84

All material Copyright © SteamLocomotive.com
Wes Barris