Etat 2-8-2 Locomotives in France

Class Details by Steve Llanso of Sweat House Media

Class 42-001 (Locobase 6070)

Data from I N Jevica's [] (visited 29 May 2004).

A burly Mikado tank used for all kinds of traffic. The design used the boiler originally supplied to a successful 2-8-0 design. But, says the French EncyclopTdie "Trains de lTgende" - Editions Atlas, reproduced on [] (accessed 15 November 2006) and translated loosely by Locobase, if the boiler was excellent, the rest was mundane and the cylinders were poorly supplied by steam passages that were too narrow (ca. 250 mm).

On the other hand, the choice of small, but not tiny drivers meant the locomotives could handle fast traffic while retaining considerable pulling power. The Nord tested this class in 1930 by hauling 500-ton passenger trains up the celebrated Survilliers grade at 72 km/h (45 mph). Trials of the class's freight-hauling ability resulted in 360 tons at 75 km/h, 740 tons at 50 km/h and 1,690 tons at 20 km/h.

In the 1930s, the Etat installed a system of bi-directional control of these locomotives, which virtually eliminated turn-around time. When the main lines were electrified, these Mikes were moved to Brittany.

Class 42-101 /141 TD (Locobase 6072)

Data from I N Jevica's [] (visited 29 May 2004).

A surprising design in some respects -- the boiler was smaller than the Etat's 42-001 while the grate stayed the same and the cylinder volume increased. Locobase wonders if Jevica's heating surface figures are close to being correct. A photograph shows a Belpaire firebox.

According to [] (accessed 9 December 2005), these Mikado tanks served trains operating between Paris and ChGteau Thierry, Gargan, Longueville, and Meaux among others. When those lines were electrified in 1955, most served out their duty in the original region until all had been retired by the end of 1960. Seven of the engines moved to the Ouest lines' depot at Batignolles

Principal Dimensions by Steve Llanso of Middle Run Media

Class42-00142-101 /141 TD
Locobase ID6070 6072
Number in Class2042
Road Numbers42-001 to 42-02042-101 to 42-140/141TD 101-140
Number Built2042
BuilderSFCM (Fives Lille), Denain
Valve GearWalschaertWalschaert
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)
Engine Weight (lbs / kg)211,864 / 96,100234,572 / 106,400
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)211,864 / 96,100234,572 / 106,400
Tender Water Capacity (gals / ML)2244 / 8.503432 / 13
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 4.40 / 4 4.40 / 4
Minimum weight of rail (calculated) (lb/yd / kg/m)
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)60.60 / 154055.90 / 1420
Boiler Pressure (psi / kPa)188.50 / 13232.10 / 16
High Pressure Cylinders (dia x stroke) (in / mm)23.62" x 25.59" / 600x65020.08" x 25.98" / 510x660 (3)
Tractive Effort (lbs / kg)37,747 / 17121.7755,455 / 25153.99
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)166.84 / 15.50186.22 / 17.30
Grate Area (sq ft / m2)30.14 / 2.8030.14 / 2.80
Evaporative Heating Surface (sq ft / m2)1829 / 169.901503 / 139.63
Superheating Surface (sq ft / m2)533 / 49.50374 / 34.76
Combined Heating Surface (sq ft / m2)2362 / 219.401877 / 174.39
Evaporative Heating Surface/Cylinder Volume140.93105.23
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation56816995
Same as above plus superheater percentage69888395
Same as above but substitute firebox area for grate area38,68351,866
Power L110,9448781
Power MT

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