Tours-Nantes 0-6-0 Locomotives in France

Class Details by Steve Llanso of Sweat House Media

Class 6 (Locobase 20421)

Data from "An Old French Locomotive", Locomotive Magazine, Volume XXI [21] (14 August 1915), pp. 188-190.

Mon. F Achard supplied the information and illustrations on these Tours a Nantes railway-designed six-coupleds, which LM noted showed some outdated concepts such as the steeply raked cylinders. Such an angle, said LM," together with the considerable overhang at front and rear, must have rendered the running very unsteady at anything but the most moderate speed." An illustration shows a straight boiler, low firebox behind the last driven axle, and a tall steam dome over the gap between the first two axles.

Despite the LM's assurances, the accompanying diagram of the firebox does not easily convey the "peculiarity" of this furnace. A longitudinal water bridge connected the front and back plates. The outer firebox walls were buttressed by stay rods passing through it. The water bridge required no staying, permitted the "free escape of steam and a brisk circulation of water." It apparently also functioned like the later brick arch, possibly assisting "combustion by deflecting the flame before its passage through the tubes." Moreover, the water in the bridge "augmented the heating surface of the firebox considerably."

LM suggested that such an arrangment of stays and bridge "must have made firing difficult, especially in getting the fuel well on to the firebars immediately under the water-bridge".

22-23 soon were sold to the Nimes-Montpellier railway. The others remained on the Tours-Nantes through the railway's integration into the Paris-Orleans.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID20421
RailroadTours-Nantes (PO)
Number in Class16
Road Numbers6-12, 22-23/51-64
Number Built16
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)
Ratio of driving wheelbase to overall engine wheelbase
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)50,905 / 23,090
Engine Weight (lbs / kg)50,905 / 23,090
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)28 / 14
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)51.20 / 1300
Boiler Pressure (psi / kPa)101.50 / 7
High Pressure Cylinders (dia x stroke) (in / mm)14.96" x 23.62" / 380x600
Tractive Effort (lbs / kg)8908 / 4040.61
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.71
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)74.49 / 6.92
Grate Area (sq ft / m2) 9.80 / 0.91
Evaporative Heating Surface (sq ft / m2)738 / 68.58
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)738 / 68.58
Evaporative Heating Surface/Cylinder Volume153.58
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation995
Same as above plus superheater percentage995
Same as above but substitute firebox area for grate area7561
Power L12002
Power MT260.11

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