Data provided by Carlos Alberto Fern+ndez Priotti in Bryan Attewell ([] Steam Locomotive simulator program (April 2000). D S Purdom, British Team on the Pampas (London and New York: Mechanical Engineering Publications, Ltd:, 1977), pp. 42-43. Works numbers were 17124-17145, 17285-17296 in 1906.
Dennis Purdom stated that this relatively large tank engine order may been originally intended for India, but was diverted to Argentina, "but it has been impossible to trace any official record of this." Many years later, Locobase was able to combine an NBLC catalogue entry with a production list to determine some of the works numbers.
The engines presented a very British sight with cylinders outside and below the running board, inside valves, black smokebox and short stack, Belapaire firebox and roofed cab with large, windowless openings. The rear two axles of the coupled trio flanked the grate front and rear and leading and trailing trucks balanced the profile.
He contended that the class was "a remarkably good investment for the railway, being real maids of all work and able to perform efficiently every possible job within their rather limited fuel and water capacity."
They even proved able to take up the slack in the "intense" Buenos Aires suburban-service motive power shortage for several years from 1924.
Data from Carlos Alberto Fern+ndez Priotti in Bryan Attewell ([] Steam Locomotive simulator program (December 2000) and from "James Nasmyth's Centenary," The Locomotive Magazine, Vol XIV (15 December 1908), p. 209-211. See also D S Purdom, British Team on the Pampas (London and New York: Mechanical Engineering Publications, Ltd:, 1977), pp. 43-44.
Switchers.
Data from Carlos Alberto Fern+ndez Priotti in Bryan Attewell ([] Steam Locomotive simulator program (December 2000); and "Superheater Tank Locomotive, Buenos Ayres Great Southern Ry", Locomotive Magazine, Volume XXV [25] (14 June 1919), p. 86; D S Purdom, British Team on the Pampas (London and New York: Mechanical Engineering Publications, Ltd:, 1977), pp. 44-45. Robert Stephenson & Company produced the first ten in 1913 (works numbers were 3471-3480). North British Locomotive followed with 31 more (works numbers 20186-20216 in 1913-1914).
Oil-burning suburban passenger tanks. They had inside admission piston valves.
LM's report noted the virtues of the 2-6-2 arrangement as applied to tank engines. Setting three driven axles between a swivelling truck at each end "gives at once ample adhesion weight and full flexibility" while being "decidedly cheaper in first cost" than a 4-6-2 or a 4-6-4 locomotive as well as being "economical of weight that is useless for adhesion."
Purdom wrote that these were the tank version of the class 7D 2-6-0 tender engines. On their arrival, he continued, "They at once took over the bulk of the Buenos Aires suburban services including the longer runs unsuitable for the class 8A due to the restricted fuel capacity of the latter."
Most operated in the Buenos Aires suburbs, but a few were delivered to Bahia Blanca and the city of Tandil.
Data from Carlos Alberto Fern+ndez Priotti in Bryan Attewell ([] Steam Locomotive simulator program (December 2000). Beyer, Peacock works numbers 6246-6260 in 1925 and North British Locomotive Company works numbers werer 23156-23170 in 1925.
-Superheated repeats of the 8DVs a dozen years later. Also used for switching (shunting) duties.
Data from Carlos Alberto Fernandez Priotti in Bryan Attewell ([] Steam Locomotive simulator program (December 2000). See also Douglas S Purdom, British Steam on the Pampas (London: Mechanical Engineering Publications, Ltd, 1977), pp. 46-47
Essentially the same as the 8C suburban passenger tanks supplied by Stephenson in the same period, but used for switching and consequently having no superheater, smaller drivers, and less water and fuel.
The Spanish-language website members.es.tripod.de/rielsud/locoayer.html (Dec 2001| quotes the last Chief Mechanic of the Sud, Douglas Purdom, as noting that throughout their working lives, these engines would leave their home shed on Sunday for Kilo 5 -- their main working area -- and not return until the following Saturday. During that week they'd be in steam continuously and pause only to have water and oil refilled.
Principal Dimensions by Steve Llanso of Middle Run Media | |||||
---|---|---|---|---|---|
Class | 8A | 8B | 8C | 8DN | 8DV |
Locobase ID | 3733 | 4298 | 4299 | 4301 | 4300 |
Railroad | FC del Sud de Buenos Aires (FCS) | FC del Sud de Buenos Aires (FCS) | FC del Sud de Buenos Aires (FCS) | FC del Sud de Buenos Aires (FCS) | FC del Sud de Buenos Aires (FCS) |
Country | Argentina | Argentina | Argentina | Argentina | Argentina |
Whyte | 2-6-2T | 2-6-2T | 2-6-2T | 2-6-2T | 2-6-2T |
Number in Class | 34 | 10 | 41 | 30 | 40 |
Road Numbers | 394-415, 456-467/3321-3354 | 3401-3410 | 3451-3491 | 3150-3179 | 3501-3510, 3150-3179 |
Gauge | 5'6" | 5'6" | 5'6" | 5'6" | 5'6" |
Number Built | 34 | 10 | 41 | 30 | 40 |
Builder | North British | Nasmyth Wilson | several | several | Robert Stephenson & Co |
Year | 1906 | 1908 | 1913 | 1926 | 1914 |
Valve Gear | Stephenson | Walschaert | Walschaert | Walschaert | Walschaert |
Locomotive Length and Weight | |||||
Driver Wheelbase (ft / m) | 14 / 4.27 | 12.83 / 3.91 | 13 / 3.96 | ||
Engine Wheelbase (ft / m) | 30.17 / 9.20 | 27.75 / 8.46 | 30.42 / 9.27 | ||
Ratio of driving wheelbase to overall engine wheelbase | 0.46 | 0.46 | 0.43 | ||
Overall Wheelbase (engine & tender) (ft / m) | 30.17 / 9.20 | 27.75 / 8.46 | 30.42 / 9.27 | ||
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 36,960 | ||||
Weight on Drivers (lbs / kg) | 109,648 / 49,736 | 102,592 / 46,535 | 110,209 / 49,990 | 112,672 / 51,107 | 110,208 / 49,990 |
Engine Weight (lbs / kg) | 165,200 / 74,934 | 137,340 / 62,296 | 152,200 / 69,037 | ||
Tender Loaded Weight (lbs / kg) | |||||
Total Engine and Tender Weight (lbs / kg) | 165,200 / 74,934 | 137,340 / 62,296 | 152,200 / 69,037 | ||
Tender Water Capacity (gals / ML) | 1440 / 5.45 | 1200 / 4.55 | 2400 / 9.09 | 1800 / 6.82 | 1800 / 6.82 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3.10 / 2.80 | 6.90 / 6.30 | 3 / 3 | 3 / 2.70 | |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 61 / 30.50 | 57 / 28.50 | 61 / 30.50 | 63 / 31.50 | 61 / 30.50 |
Geometry Relating to Tractive Effort | |||||
Driver Diameter (in / mm) | 62 / 1575 | 52 / 1321 | 68 / 1727 | 55.50 / 1410 | 55.50 / 1410 |
Boiler Pressure (psi / kPa) | 180 / 1240 | 184.20 / 1270 | 160 / 1100 | 152.30 / 1050 | 152.30 / 1050 |
High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 26" / 457x660 | 17" x 24" / 432x610 (3) | 19" x 26" / 483x660 | 19" x 26" / 483x660 | 19" x 26" / 483x660 |
Tractive Effort (lbs / kg) | 20,788 / 9429.29 | 31,326 / 14209.25 | 18,772 / 8514.85 | 21,893 / 9930.51 | 21,893 / 9930.51 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.27 | 3.27 | 5.87 | 5.15 | 5.03 |
Heating Ability | |||||
Tubes (number - dia) (in / mm) | |||||
Flues (number - dia) (in / mm) | |||||
Flue/Tube length (ft / m) | 11 / 3.35 | 10.70 / 3.26 | 10.70 / 3.26 | 10.70 / 3.26 | 10.70 / 3.26 |
Firebox Area (sq ft / m2) | 148 / 13.75 | 99 / 9.20 | |||
Grate Area (sq ft / m2) | 27 / 2.51 | 20 / 1.86 | 21.96 / 2.04 | 22 / 2.04 | 22 / 2.04 |
Evaporative Heating Surface (sq ft / m2) | 1660 / 154.22 | 1245 / 115.66 | 1153 / 107.12 | 1153 / 107.16 | 1386 / 128.76 |
Superheating Surface (sq ft / m2) | 242 / 22.48 | 242 / 22.49 | |||
Combined Heating Surface (sq ft / m2) | 1660 / 154.22 | 1245 / 115.66 | 1395 / 129.60 | 1395 / 129.65 | 1386 / 128.76 |
Evaporative Heating Surface/Cylinder Volume | 216.78 | 131.64 | 135.14 | 135.14 | 162.45 |
Computations Relating to Power Output (More Information) | |||||
Robert LeMassena's Power Computation | 4860 | 3684 | 3514 | 3351 | 3351 |
Same as above plus superheater percentage | 4860 | 3684 | 4111 | 3920 | 3351 |
Same as above but substitute firebox area for grate area | 26,640 | 18,236 | |||
Power L1 | 5829 | 2937 | |||
Power MT | 351.60 | 189.34 |