E. de F. Itaqui-Sao Borja 4-6-2 Locomotives in Brazil


Class Details by Steve Llanso of Sweat House Media

Class Sao Borja (Locobase 4424)

Data from narrowmind.railfan.net, supplemented and amended by DeGolyer, Vol 79, pp. 244+. Works number was 60366 in January 1928.

Outside valves and cylinders used a Walschaerts valve gear, straight stack on this small Pacific. The impressive direct heating surface area included 8 sq ft (0.75 sq m) of arch tubes and 19 sq ft (1.75 sq m) in the combustion chamber. Even for this narrow a gauge, the 6" (152 mm) diameter of the piston valves seems small.

Itaqui is in the southeastern part of Brazil, near Paraguay and this railway offered relatively generous curve radii of 80 metres (262 feet) and maximum grades of 2%.

Principal Dimensions by Steve Llanso of Middle Run Media

ClassSao Borja
Locobase ID4424
RailroadE. de F. Itaqui-Sao Borja
CountryBrazil
Whyte4-6-2
Number in Class1
Road Numbers14
Gaugemetre
Number Built1
BuilderBaldwin
Year1928
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)8 / 2.44
Engine Wheelbase (ft / m)23.17 / 7.06
Ratio of driving wheelbase to overall engine wheelbase 0.35
Overall Wheelbase (engine & tender) (ft / m)46.52 / 14.18
Axle Loading (Maximum Weight per Axle) (lbs / kg)15,428
Weight on Drivers (lbs / kg)42,100 / 19,096
Engine Weight (lbs / kg)78,900 / 35,788
Tender Loaded Weight (lbs / kg)58,000 / 26,308
Total Engine and Tender Weight (lbs / kg)136,900 / 62,096
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)23 / 11.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)42 / 1067
Boiler Pressure (psi / kPa)170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)13" x 20" / 330x508
Tractive Effort (lbs / kg)11,629 / 5274.83
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.62
Heating Ability
Tubes (number - dia) (in / mm)62 - 2" / 51
Flues (number - dia) (in / mm)10 - 5.375" / 137
Flue/Tube length (ft / m)12 / 3.66
Firebox Area (sq ft / m2)103 / 9.57
Grate Area (sq ft / m2)20.20 / 1.88
Evaporative Heating Surface (sq ft / m2)658 / 61.13
Superheating Surface (sq ft / m2)136 / 12.63
Combined Heating Surface (sq ft / m2)794 / 73.76
Evaporative Heating Surface/Cylinder Volume214.16
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation3434
Same as above plus superheater percentage4018
Same as above but substitute firebox area for grate area20,487
Power L19284
Power MT1458.51

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