Data from VGN 8 - 1951 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Mallet Articulated Compound Locomotives, 2-6-6-0 ...", American Engineering and Railroad Journal, Volume 83, No 6, (June 1909), p. 261 and No. 9 (September 1909), pp. 357-359. (Thanks to Chris Hohl for his 30 May 2013 email asking me to clarify this class's tender capacities.) Works numbers were 48976-48977 in August 1909, 45978 in October, and 45979 in November.
Four-cylinder Mallet compounds that were not well loved by its firemen because they were hand-bombed and not superheated. They were delivered with tenders holding 14 tons (12.7 tonnes) of coal.
All but 503 received both mechanical stokers and superheaters later on. See Locobase 7487
Data from VGN 8 - 1951 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 30 May 2013 email asking me to clarify this class's tender capacities.)
As noted in Locobase 291, the Richmond engines were delivered with saturated boilers and their hand-bombed fireboxes required a lot of effort on part of the firemen. All but the 503 later received both mechanical stokers and superheaters later on. At some point, possibly when they were upgraded, these Mallets' tender capacities were increased to 15 tons.
Like the earlier compounds, these upgraded Mallets were retired on 31 December 1933.
Data from Wiener (1930) gives mixed data, including superheater heating surface but not including the flue tube count or size and Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 35, pp. 113-120 for highly detailed specs. (Thanks to Chris Hohl for his 30 June 2021 email correcting the engine wheel base and driver diameter.) Works numbers were 35302-35309 in October 1910.
Locobase 291 shows the first four 2-6-6-0 Mallets delivered by Richmond as saturated-boiler compounds. Baldwin's contribution featured its low-temperature smokebox superheater that provided some additional drying. 30 sq ft (2.8 sq m) of firebox heating surface came in the form of six arch tubes.
Drury (1993) notes that these locomotives were more powerful than many other 2-6-6-2s. On slow coal drags, their small drivers, lack of a trailing axle, and large LP cylinders weren't disabilities. They served the VGN for not quite 25 years before being retired in December 1933.
Principal Dimensions by Steve Llanso of Middle Run Media | |||
---|---|---|---|
Class | AA | AA - superheated | AC |
Locobase ID | 291 | 7487 | 3564 |
Railroad | Virginian (VGN) | Virginian (VGN) | Virginian (VGN) |
Country | USA | USA | USA |
Whyte | 2-6-6-0 | 2-6-6-0 | 2-6-6-0 |
Number in Class | 4 | 3 | 8 |
Road Numbers | 500-503 | 500-502 | 510-517 |
Gauge | Std | Std | Std |
Number Built | 4 | 3 | 8 |
Builder | Alco-Richmond | VGN | Baldwin |
Year | 1909 | 1922 | 1910 |
Valve Gear | Walschaert | Walschaert | Walschaert |
Locomotive Length and Weight | |||
Driver Wheelbase (ft / m) | 22 / 6.71 | 22 / 6.71 | 21.34 / 6.50 |
Engine Wheelbase (ft / m) | 39.92 / 12.17 | 39.92 / 12.17 | 40.33 / 12.29 |
Ratio of driving wheelbase to overall engine wheelbase | 0.55 | 0.55 | 0.53 |
Overall Wheelbase (engine & tender) (ft / m) | 73.23 / 22.32 | 72.06 / 21.96 | 74.70 / 22.77 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | |||
Weight on Drivers (lbs / kg) | 312,000 / 141,521 | 295,600 / 134,082 | 356,800 / 161,842 |
Engine Weight (lbs / kg) | 330,000 / 149,686 | 311,300 / 141,203 | 385,300 / 174,769 |
Tender Loaded Weight (lbs / kg) | 172,000 / 78,018 | 172,000 / 78,018 | 181,700 / 82,418 |
Total Engine and Tender Weight (lbs / kg) | 502,000 / 227,704 | 483,300 / 219,221 | 567,000 / 257,187 |
Tender Water Capacity (gals / ML) | 9500 / 35.98 | 9500 / 35.98 | 9500 / 35.98 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 14 / 13 | 15 / 14 | 15 / 14 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 87 / 43.50 | 82 / 41 | 99 / 49.50 |
Geometry Relating to Tractive Effort | |||
Driver Diameter (in / mm) | 54 / 1372 | 54 / 1372 | 56 / 1422 |
Boiler Pressure (psi / kPa) | 200 / 1380 | 200 / 1380 | 210 / 1450 |
High Pressure Cylinders (dia x stroke) (in / mm) | 22" x 30" / 559x762 | 22" x 30" / 559x762 | 24" x 32" / 610x813 |
Low Pressure Cylinders (dia x stroke) (in / mm) | 35" x 30" / 889x762 | 35" x 30" / 889x762 | 36" x 32" / 914x813 |
Tractive Effort (lbs / kg) | 65,531 / 29724.40 | 65,531 / 29724.40 | 81,349 / 36899.33 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.76 | 4.51 | 4.39 |
Heating Ability | |||
Tubes (number - dia) (in / mm) | 390 - 2.25" / 57 | 207 - 2.25" / 57 | 437 - 2.25" / 57 |
Flues (number - dia) (in / mm) | 36 - 5.5" / 140 | ||
Flue/Tube length (ft / m) | 21 / 6.40 | 21 / 6.40 | 21 / 6.40 |
Firebox Area (sq ft / m2) | 223.90 / 20.80 | 223 / 20.72 | 264 / 24.53 |
Grate Area (sq ft / m2) | 57 / 5.30 | 57 / 5.30 | 78 / 7.25 |
Evaporative Heating Surface (sq ft / m2) | 5066 / 470.82 | 3855 / 358.27 | 5641 / 524.06 |
Superheating Surface (sq ft / m2) | 878 / 81.60 | 742 / 68.93 | |
Combined Heating Surface (sq ft / m2) | 5066 / 470.82 | 4733 / 439.87 | 6383 / 592.99 |
Evaporative Heating Surface/Cylinder Volume | 383.69 | 291.97 | 336.76 |
Computations Relating to Power Output (More Information) | |||
Robert LeMassena's Power Computation | 11,400 | 11,400 | 16,380 |
Same as above plus superheater percentage | 11,400 | 13,566 | 18,346 |
Same as above but substitute firebox area for grate area | 44,780 | 53,074 | 62,093 |
Power L1 | 3333 | 6936 | 7091 |
Power MT | 141.31 | 310.38 | 262.89 |