Data from "Compound Tank Locomotive", Engineering, Volume 44 (23 December 1887), pp. 649-650 and for illustration, same publication, 1 July 1887, p 13 and p 652. See also Raymond, "LNW Compound Goods Tank", English Mechanic and World of Science, 29 July 1887, p. 513 and August 1887, p. 539; and See also F W Webb, "Development of the Crewe System of Compounding Locomotives," Engineering Review, Volume 2, (20 June 1895), pp. 391-393. (Thanks to Alexander Blessing for his 5 February 2023 email noting a different grate area and giving the best Whyte interpretation of Webb's divided drive.)
This was a typical Webb compound that used divided drive and the 2:1 cylinder arrangement. The two outside cylinders drove on the second axle and turned that and the third axle. The leading driven axle had its own cylinder, the 20" LP can located between the frames under the smokebox that turned a full-cranked axle.
Steamindex describes it as the fourth compound tank, noting that it operated on the Manchester and Buxton branches for a few years. It used the boiler and grate of the 0-6-2T Coal Tanks (Locobase 2172), but using a leading truck and the 3-cylinder compound drive train.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Webb compound goods |
| Locobase ID | 9543 |
| Railroad | London & North Western |
| Country | Great Britain |
| Whyte | 2-2-4-0T |
| Number in Class | 1 |
| Road Numbers | 2974 / 777 |
| Gauge | Std |
| Number Built | 1 |
| Builder | GWR - Wolverhampton |
| Year | 1887 |
| Valve Gear | Joy |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 14 / 4.27 |
| Engine Wheelbase (ft / m) | 21.50 / 6.55 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.65 |
| Overall Wheelbase (engine & tender) (ft / m) | 21.50 / 6.55 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 33,600 / 15,241 |
| Weight on Drivers (lbs / kg) | 94,640 / 42,928 |
| Engine Weight (lbs / kg) | 123,200 / 55,883 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | 123,200 / 55,883 |
| Tender Water Capacity (gals / ML) | 1680 / 6.36 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3.30 / 3 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 62.50 / 1588 |
| Boiler Pressure (psi / kPa) | 160 / 1100 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 14" x 24" / 356x610 |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 30" x 24" / 762x610 (1) |
| Tractive Effort (lbs / kg) | 12,608 / 5718.90 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 7.51 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 198 - 1.875" / 48 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 10.34 / 3.15 |
| Firebox Area (sq ft / m2) | 94.60 / 8.79 |
| Grate Area (sq ft / m2) | 17.33 / 1.61 |
| Evaporative Heating Surface (sq ft / m2) | 1099 / 102.10 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1099 / 102.10 |
| Evaporative Heating Surface/Cylinder Volume | 257.01 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2773 |
| Same as above plus superheater percentage | 2773 |
| Same as above but substitute firebox area for grate area | 15,136 |
| Power L1 | 2669 |
| Power MT | |