Caledonian 2-6-0 Locomotives in Great_Britain

Class Details by Steve Llanso of Sweat House Media

Class 34/3F (Locobase 20141)

Data from "Caledonian Railway", Locomotive Magazine, Volume 19 (15 August 1913), p. 181. See also Steamindex's disimissive description of the design at [], last accessed 9 January 2017 and Alex K Bowman, "The McIntosh Locomotives of the Caledonian Railway", Railway Magazine, Volume XXXIV, January-June 1914 , pp. 201-210.

It's not often mentioned that superheating an existing design added considerable weight. In the case of this quintet, fitting the 812 0-6-0 design described in Locobase 5538 with a superheater added 2 1/2 tons (5,600 lb or 2,540 kg). "The extra weight," noted the LM report," is largely in the neighbourhood of the smokebox and cylinders." So the Caley tacked on a truck to carry the weight and turned the six-coupled into Moguls; as such, they were often described as the "Converted 30 class" because some 652s had been superheated in 1912.

John McIntosh took the opportunity to increase cylinder diameters by an inch and feed them steam through 8" (203 mm) piston valves. Steamindex observed that the truck had lateral springing, but, although resembling a radial truck, didn't have the curved guides normally associated with them. Yet the LM report said that the leading truck's inclusion also stemmed from "the inducement of greater safety at high speeds in the provision of a leading truck" adding that in service "these engines have been noted for smooth and easy running."

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID20141
CountryGreat Britain
Number in Class5
Road Numbers34-38
Number Built5
BuilderSt. Rollox
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)16.75 / 5.11
Engine Wheelbase (ft / m)16.75 / 5.11
Ratio of driving wheelbase to overall engine wheelbase1
Overall Wheelbase (engine & tender) (ft / m)38.60 / 11.77
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)103,040 / 46,738
Engine Weight (lbs / kg)121,520 / 55,121
Tender Loaded Weight (lbs / kg)83,440 / 37,848
Total Engine and Tender Weight (lbs / kg)204,960 / 92,969
Tender Water Capacity (gals / ML)3600 / 13.64
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 4.68 / 4
Minimum weight of rail (calculated) (lb/yd / kg/m)57 / 28.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)60 / 1524
Boiler Pressure (psi / kPa)160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)19.5" x 26" / 495x660
Tractive Effort (lbs / kg)22,409 / 10164.56
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.60
Heating Ability
Tubes (number - dia) (in / mm)161 - 1.75" / 44
Flues (number - dia) (in / mm)21 - 5.125" / 130
Flue/Tube length (ft / m)10.50 / 3.20
Firebox Area (sq ft / m2)118.78 / 11.03
Grate Area (sq ft / m2)20.60 / 1.91
Evaporative Heating Surface (sq ft / m2)1190 / 110.55
Superheating Surface (sq ft / m2)270 / 25.08
Combined Heating Surface (sq ft / m2)1460 / 135.63
Evaporative Heating Surface/Cylinder Volume132.41
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation3296
Same as above plus superheater percentage3889
Same as above but substitute firebox area for grate area22,426
Power L17502
Power MT481.53

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