Belfast & County Down 4-6-4 Locomotives in Ireland
Class Details by Steve Llanso of Sweat House Media
Class 22 (Locobase 2760)
Data from 1946 Beyer, Peacock catalogue hosted on Martyn Bane's website at [
] (accessed 21 May 2006). See also "4-6-4 Tank Locomotive, Belfast and County Down Ry", Locomotive Magazine, Volume XXVI [26] (15 September 1920), p. 191; and "Belfast & County Down Railway" on J
John Speller's Web Pages - Irish Railways at [], last accessed 21 July 2020. Works numbers were 5999-6002 in 1919.
These entered service in suburban commuter service around Belfast. OS Nock (RWC IV, pl 177) notes that the designer -- JL Crosthwait of the B&CD -- felt a superheater was superfluous for such short-range engines. LM's 1920 report waxed eloquent about the running gear. "Inside admission piston valves driven by Walschaert's gear effect the steam distribution, and it will be noticed that all the motion is external, and of light and elegant design, especially in regard to moving parts."
John Speller's caption under a BCDR 4-6-4T asserts that they "proved to be ridiculously large for the moderate traffic of the line."
An article on Irish Baltic tanks (W.T. Scott. 98-100) in Backtrack's Vol 2, Number 8 and summarized in steamindex ([]) says this quartet was produced when the Board of Directors grew enamored of similar locomotives on the London, Brighton & South Coast Railway. The summary reports: "These arrived in 1920, but were heavy of fuel due to a poor front-end. The UTA attempted to improve the design."
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 22 |
| Locobase ID | 2760 |
| Railroad | Belfast & County Down |
| Country | Ireland |
| Whyte | 4-6-4T |
| Number in Class | 4 |
| Road Numbers | 22-25/222-225 |
| Gauge | 5'3" |
| Number Built | 4 |
| Builder | Beyer, Peacock |
| Year | 1920 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 12.67 / 3.86 |
| Engine Wheelbase (ft / m) | 35.25 / 10.74 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.36 |
| Overall Wheelbase (engine & tender) (ft / m) | 35.25 / 10.74 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 34,496 / 15,647 |
| Weight on Drivers (lbs / kg) | 104,560 / 47,428 |
| Engine Weight (lbs / kg) | 137,984 / 62,589 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 2400 / 9.09 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4.50 / 4 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 58 / 29 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 66 / 1676 |
| Boiler Pressure (psi / kPa) | 170 / 1170 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 19" x 26" / 483x660 |
| Tractive Effort (lbs / kg) | 20,550 / 9321.33 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.09 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 243 - 1.875" / 48 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 12.56 / 3.83 |
| Firebox Area (sq ft / m2) | 124.50 / 11.57 |
| Grate Area (sq ft / m2) | 24.70 / 2.29 |
| Evaporative Heating Surface (sq ft / m2) | 1622 / 150.69 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1622 / 150.69 |
| Evaporative Heating Surface/Cylinder Volume | 190.11 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 4199 |
| Same as above plus superheater percentage | 4199 |
| Same as above but substitute firebox area for grate area | 21,165 |
| Power L1 | 4919 |
| Power MT | 311.15 |