South Manchurian 4-6-0 Locomotives in Japan

Class Details by Steve Llanso of Sweat House Media

Class 602 (Locobase 20193)

Data from Catalogue 10036--Locomotives for Export (New York City, April 1910), pp. 47-48. Works numbers were 44682-44699 in March 1908.

This class of Ten-wheelers immediately preceded the seven Pacifics on Richmond's production line (Locobase 20190). Locobase notes in both entries that their common destination, identical boiler pressure and passenger-scaled driver diameter allow a direct comparison between a 4-6-0 and a 4-6-2 by the same builder in the same period of design transtion.

Here are some numbers: the Pacific weighed 19 tons more than the 4-6-0 but put a little less weight on the drivers; driving wheelbase was actually shorter, but the extra axle contributed to the 8 foot (2.44 m) longer engine wheelbase .Cylinder volume in the 4-6-2 increased by 20%, which was matched by the 25% increase in evaporative heating surface area and grate area by 56%, but the latter lay at the bottom of a wider firebox that was shorter and much shallower. As a result, the Pacific had slightly less total direct heating surface area.

Principal Dimensions by Steve Llanso of Middle Run Media

Locobase ID20193
RailroadSouth Manchurian
Number in Class18
Road Numbers602-619
Number Built18
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)14.50 / 4.42
Engine Wheelbase (ft / m)24.67 / 7.52
Ratio of driving wheelbase to overall engine wheelbase 0.59
Overall Wheelbase (engine & tender) (ft / m)52.75 / 16.08
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)121,500 / 55,112
Engine Weight (lbs / kg)158,500 / 71,894
Tender Loaded Weight (lbs / kg)107,100 / 48,580
Total Engine and Tender Weight (lbs / kg)265,600 / 120,474
Tender Water Capacity (gals / ML)5000 / 18.94
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)10 / 9
Minimum weight of rail (calculated) (lb/yd / kg/m)68 / 34
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)69 / 1753
Boiler Pressure (psi / kPa)200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)19" x 24" / 483x610
Tractive Effort (lbs / kg)21,346 / 9682.39
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.69
Heating Ability
Tubes (number - dia) (in / mm)268 - 2" / 51
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)14.25 / 4.34
Firebox Area (sq ft / m2)162 / 15.05
Grate Area (sq ft / m2)32.40 / 3.01
Evaporative Heating Surface (sq ft / m2)2150 / 199.74
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2150 / 199.74
Evaporative Heating Surface/Cylinder Volume272.99
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation6480
Same as above plus superheater percentage6480
Same as above but substitute firebox area for grate area32,400
Power L18644
Power MT470.54

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