Ballymena & Larne 2-4-0 Locomotives in Ireland

Class Details by Steve Llanso of Sweat House Media

Class P (Locobase 10224)

Data from "Narrow-Gauge Locomotives of the Belfast and Northern Counties RY," The Locomotive Magazine, Vol VII (May 1902), p. 92. Boiler pressure is an estimate. Works numbers were 1687 and 1828.

The Ballymena & Larne ran 32 miles in County Antrim, serving the iron ore deposits as well as carrying passengers. These locomotives opened the line, or at least the Larne to Ballyclare section. It was only 12 years before declining revenues forced the line to be taken over by the Belfast & Northern Counties system.

BP's two engines were delivered 3 years apart and differed only in details. They were similar to the Isle of Man locomotives delivered in the same period.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID10224
RailroadBallymena & Larne
Number in Class1
Road Numbers1, 4 / 104-105
Number Built1
BuilderBeyer, Peacock
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)8 / 2.44
Engine Wheelbase (ft / m)14.25 / 4.34
Ratio of driving wheelbase to overall engine wheelbase 0.56
Overall Wheelbase (engine & tender) (ft / m)14.25 / 4.34
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)35,840 / 16,257
Engine Weight (lbs / kg)47,040 / 21,337
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)47,040 / 21,337
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)30 / 15
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)45 / 1143
Boiler Pressure (psi / kPa)140 / 9.70
High Pressure Cylinders (dia x stroke) (in / mm)11" x 18" / 279x457
Tractive Effort (lbs / kg)5760 / 2612.70
Factor of Adhesion (Weight on Drivers/Tractive Effort) 6.22
Heating Ability
Tubes (number - dia) (in / mm)88 - 1.625" / 41
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)45.37 / 4.22
Grate Area (sq ft / m2) 6.85 / 0.64
Evaporative Heating Surface (sq ft / m2)343 / 31.88
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)343 / 31.88
Evaporative Heating Surface/Cylinder Volume173.24
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation959
Same as above plus superheater percentage959
Same as above but substitute firebox area for grate area6352
Power L13022
Power MT371.78

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