Dombes et du Sud-Est / PLM 2-4-0 Locomotives in France


Class Details by Steve Llanso of Sweat House Media

Class 2 / 3 638 / 5 638 (Locobase 13430)

Data from [], last accessed 13 November 2011.

This quartet was originally delivered by Koechlin into terminal switching service in 1865. In 1888, they entered a second career as locomotives of light, local trains. So reconditioned, the class remained in service until 1908 (5 640) and 1909 (5 638-5 6398, 5 641).


Class 6 / 671 (Locobase 13405)

Data from Wiki PLM [], last accessed on 10 November 2011.

Specifications for 1884 updated version. Both engines were retired in 1905.

Principal Dimensions by Steve Llanso of Sweat House Media

Class2 / 3 638 / 5 6386 / 671
Locobase ID13430 13405
RailroadDombes et du Sud-Est / PLMDombes et du Sud-Est / PLM
CountryFranceFrance
Whyte2-4-0T2-4-0
Number in Class42
Road Numbers2-5 / 3 638-3 641 / 5 638-5 6416-7 / 671-672
GaugeStdStd
Number Built42
BuilderPLMKoechlin
Year18881868
Valve GearStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 6.56 / 2 6.04 / 1.84
Engine Wheelbase (ft / m)13.45 / 4.1011.48 / 3.50
Ratio of driving wheelbase to overall engine wheelbase 0.49 0.53
Overall Wheelbase (engine & tender) (ft / m)13.45 / 4.10
Axle Loading (Maximum Weight per Axle) (lbs / kg)28,418 / 12,89025,684 / 11,650
Weight on Drivers (lbs / kg)56,835 / 25,78051,368 / 23,300
Engine Weight (lbs / kg)81,306 / 36,88070,041 / 31,770
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)81,306 / 36,880
Tender Water Capacity (gals / ML)1045 / 3.96
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 1.70 / 2
Minimum weight of rail (calculated) (lb/yd / kg/m)47 / 23.5043 / 21.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)57.10 / 145065 / 1650
Boiler Pressure (psi / kPa)120.40 / 8.30120.40 / 8.30
High Pressure Cylinders (dia x stroke) (in / mm)14.96" x 12.2" / 380x31016.54" x 22.05" / 420x560
Tractive Effort (lbs / kg)4894 / 2219.889498 / 4308.23
Factor of Adhesion (Weight on Drivers/Tractive Effort)11.61 5.41
Heating Ability
Tubes (number - dia) (in / mm)184 - 1.969" / 50
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)10.24 / 3.12
Firebox Area (sq ft / m2)64.80 / 6.0274.81 / 6.95
Grate Area (sq ft / m2)11.41 / 1.0613.89 / 1.29
Evaporative Heating Surface (sq ft / m2)898 / 83.411206 / 112.03
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)898 / 83.411206 / 112.03
Evaporative Heating Surface/Cylinder Volume361.81219.93
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation13741672
Same as above plus superheater percentage13741672
Same as above but substitute firebox area for grate area78029007
Power L156413758
Power MT437.63322.57

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