kaiserlich-Koeniglichen Oesterreichischen StB 4-6-2 Locomotives in Austria


Class Details by Steve Llanso of Sweat House Media

Class 629 / 77 (Locobase 4709)

Data from [link], accessed 4 August 2006.

The wikipedia entry says this began as a 15-engine class for the Sudbahn to replace the 229 in light express passenger service. A demand for more power and the consequent increase in weight led to the adoption of the 4-6-2T arrangement. Such was the timing of world events and the development of locomotive types that this is the only such design of that wheel arrangement that Austrian railways would ever adopt.

Finding that the 629s ran smoothly, quietly, and could easily hit 85 km/h (57 mph), the kKStB ordered more. Ultimately, when the kkStB had been superseded by the BB+, the class was numbered as follows (in order of construction):

Earlier class Years built

77.66-80 629,01-15 1913-1915

77.01-10 629.01-25 1917-1918

77.11-40 629.26-55 1920-1922

77.242-264 629.57-80 1926-1927

77.281-285 formerly from BB+ row 629,500-504 (year of construction 1927/28)

Principal Dimensions by Steve Llanso of Middle Run Media
Class629 / 77
Locobase ID4709
Railroadkaiserlich-Koeniglichen Oesterreichischen StB (kKStB)
CountryAustria
Whyte4-6-2T
Number in Class85
Road Numbers629.01 - 629.80
GaugeStd
Number Built85
Builderseveral
Year1913
Valve GearHeusinger
Locomotive Length and Weight
Driver Wheelbase (ft / m)11.81 / 3.60
Engine Wheelbase (ft / m)31.46 / 9.59
Ratio of driving wheelbase to overall engine wheelbase 0.38
Overall Wheelbase (engine & tender) (ft / m)31.46 / 9.59
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)99,208 / 45,000
Engine Weight (lbs / kg)184,747 / 83,800
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)3168 / 12
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 3.50 / 3
Minimum weight of rail (calculated) (lb/yd / kg/m)55 / 27.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63.50 / 1614
Boiler Pressure (psi / kPa)188.50 / 1300
High Pressure Cylinders (dia x stroke) (in / mm)18.7" x 28.35" / 475x720
Tractive Effort (lbs / kg)25,015 / 11346.63
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.97
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)131.27 / 12.20
Grate Area (sq ft / m2)29.05 / 2.70
Evaporative Heating Surface (sq ft / m2)1526 / 141.85
Superheating Surface (sq ft / m2)363 / 33.75
Combined Heating Surface (sq ft / m2)1889 / 175.60
Evaporative Heating Surface/Cylinder Volume169.33
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation5476
Same as above plus superheater percentage6516
Same as above but substitute firebox area for grate area29,446
Power L112,063
Power MT804.20

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