Soviet State 4-8-4 Locomotives in Russia

Class Details by Steve Llanso of Sweat House Media

Class P36 (Locobase 739)

Data from Ransome-Wallis (1959), Hollingsworth (1982, Reder (1974); and [] (a Ukrainian website organizing steam tours), using information from Anthony J. Heywood & Jan D.C. Button, Soviet Locomotive Types: The Union Legacy (1995). See also "Our P36 Locomotive" account found on the Golden Eagle Luxury Trains website at [], last accessed 29 October 2019; and "2-4-2 " in 1935 p 158

The only 4-8-4s Soviet railroaders ever built, but among the latest of this wheel arrangement to have been constructed and the most numerous single class. They became known for their distinctive casing, which included ribbed "elephant ear" smoke deflectors forward, a casing for the steam pipe that ran the length of the boiler on top, Boxpok-type drivers and greenish-tinged boiler. They ran well and saw out steam on Soviet railways, operating both as premier express engines and later as all-purpose mixed-traffic types.

(See the Golden Eagle account of the recovery of the P36.0032 from a stationary boiler end in Siberian Chita.)

Ransome-Wallis and Hollingsworth have nearly identical superheater surface areas at around 1,535 sq ft (142.6 sq m). But both Reder (1974) and the [] website reported 1,417 and 1,421 sq ft respectively. Locobase chooses the last because it's the most recent and comes from what has been described as a definitive source.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID739
RailroadSoviet State
CountrySoviet Union
Number in Class250
Road NumbersP36.0001-P36.0251
Number Built250
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)19.19 / 5.85
Engine Wheelbase (ft / m)44.13 / 13.45
Ratio of driving wheelbase to overall engine wheelbase 0.43
Overall Wheelbase (engine & tender) (ft / m)86.55 / 26.38
Axle Loading (Maximum Weight per Axle) (lbs / kg)40,124 / 18,200
Weight on Drivers (lbs / kg)159,614 / 72,400
Engine Weight (lbs / kg)293,655 / 133,200
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)12,038 / 45.60
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)26.40 / 24
Minimum weight of rail (calculated) (lb/yd / kg/m)67 / 33.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)72.80 / 1850
Boiler Pressure (psi / kPa)213.20 / 14.70
High Pressure Cylinders (dia x stroke) (in / mm)22.64" x 31.5" / 575x800
Tractive Effort (lbs / kg)40,192 / 18230.81
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)19.69 / 6
Firebox Area (sq ft / m2)212.05
Grate Area (sq ft / m2)72.66 / 6.75
Evaporative Heating Surface (sq ft / m2)2618 / 243.20
Superheating Surface (sq ft / m2)1421 / 132
Combined Heating Surface (sq ft / m2)4039 / 375.20
Evaporative Heating Surface/Cylinder Volume178.37
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation15,491
Same as above plus superheater percentage20,913
Same as above but substitute firebox area for grate area61,032
Power L129,023
Power MT1603.49

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