Messrs Cadbury Bros, Ltd 0-4-0 Locomotives in Great_Britain

Class Details by Steve Llanso of Sweat House Media

Class Bournville No 4 (Locobase 20142)

Data from "Tank Locomotive for Messrs. Cadbury Brothers, Ltd", Locomotive Magazine, Volume 19 (15 February 1913), p. 29. See also "Railways of Worcestershire"at [], last accessed 10 January 2017. Works numbers were 1589 in 1910, 1669 in 1913, 1921 in 1923, and 1977 in 1925.

The LM report on this typical industrial switcher noted an untypical installation of outside constant-lead radial valve gear instead of the usual inside Stephenson link Louis Barrow, Cadbury's engineer, noted that a tight minimum curve radius of 120 feet required a short wheelbase and good balance overall, conditions for which the Walschaert gear was well suited "as with this type of valve gear and outside cylinders, the front of the firebox can be close up to the driving axle." Moreover, leading axle bearings measured 8" (203 mm) in diameter and 7 1/2" (191 mm) long while the driving axle bearings were even bigger at 8 1/2" () diameter and 10" long. These were unusually large in such an engine.

The Bournville cocoa and chocolate works at Bournville near Birmingham had a railway with a ruling gradient reaching 1 in 42 (1.25%). Trains of up to 20 ten-ton wagons were to be expected. "We understand this engine ...has proved most satisfactory, said the report. "In particular the Walschaert gear has shown itself both reliable and economical, the wear being extremely small."

Locobase has used the very clear and helpful photographs from the Railways of Worcestershire site to conclude that all four Avonsides were built to the same design, even though production spanned 15 years.

4 was scrapped in February 1954, 5 followed in June 1959. 6 was sold in January 1964. 1 was preserved in January 1963 for preservation.

Principal Dimensions by Steve Llanso of Sweat House Media

ClassBournville No 4
Locobase ID20142
RailroadMessrs Cadbury Bros, Ltd
CountryGreat Britain
Number in Class4
Road Numbers4-6, 1
Number Built4
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.50 / 2.29
Engine Wheelbase (ft / m) 7.50 / 2.29
Ratio of driving wheelbase to overall engine wheelbase1
Overall Wheelbase (engine & tender) (ft / m) 7.50 / 2.29
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)76,160 / 34,546
Engine Weight (lbs / kg)76,160 / 34,546
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)76,160 / 34,546
Tender Water Capacity (gals / ML)1200 / 4.55
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 0.55 / 1
Minimum weight of rail (calculated) (lb/yd / kg/m)63 / 31.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)40.50 / 1029
Boiler Pressure (psi / kPa)175 / 12.10
High Pressure Cylinders (dia x stroke) (in / mm)16" x 22" / 406x559
Tractive Effort (lbs / kg)20,685 / 9382.57
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.68
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)
Grate Area (sq ft / m2)12.50 / 1.16
Evaporative Heating Surface (sq ft / m2)836 / 77.67
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)836 / 77.67
Evaporative Heating Surface/Cylinder Volume163.29
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2188
Same as above plus superheater percentage2188
Same as above but substitute firebox area for grate area
Power L1
Power MT

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