Some data from OS Nock (RWC II, Pl 126); see also Minutes of proceedings of the Institution of Civil Engineers, Vol 120 (London: Institution of Civil Engineers, 1895), esp. 72-74. See also John Forsythe (Archive Officer, Transport House), Steam Locomotive Data, Public Transport Commission of NSW [New South Wales], July 1974, p. 74, archived at [], last accessed 12 March 2015. (Many thanks to Brett Fitzpatrick for his 11March 2015 email supplying the link to the CoalsToNewcastle website.)
Nock comments on their "typically British " appearance -- "very neat and handsomely proportioned" -- and adds: "They made a deep impression in England, where engineers of wide experience considered them to be in advance of contemporary practice on the 'home' railways." Presumably, this refers to the relative size and power of the locomotives rather than any obvious difference in construction or basic design.
Mr Burnett of the NSWGR, commenting on a series of papers on mountain railroading noted with pride the quality of the B-P product: "They had been designed to take heavy loads up the 1 in 30 and 1 in 33 inclines, laid with 8-chain reverse curves, over the Blue mountains, which rose 3,300 feet in 30 miles. They possessed all the special features claimed for the American engine by its advocates, in having abundant vertical and lateral flexibility, balance beams being provided to all the coupled axles, in conjunction with a short rigid wheel-base, not exceeding 11 feet, while they had all the good characteristics of the English locomotive in respect of simplicity of design and substantiality and finish of detail. And yet, while they were powerful and substantial, they were amongst the lightest engines for their power that were ever constructed."
Indeed, and so positive was the reception for the first 20 that "...fifty more had been added by his successors to the same drawings, while more recently a considerable number had been added to the stock by other makers, only very slightly altered from his [Burnett's] design, the main alteration being a slight increase in the ratio of heating-surface to grate-area."
Warming to his task of placing laurels on the Mother Country's locomotive-manufacture prowess, Burnett cite the challenge presented to his successor by the advocates of American engines wherein the Z25s were tested against engines made in the United States of the same type, but with somewhat larger driving-wheels. The outcome, he asserts, was not in doubt:
"The result of the challenge was that a set trial under Government auspices was made, which brought out the capacities of the two engines in question, and the American engine was badly beaten."
Locobase elides some of the particulars to present the masterstroke:
"That performance gave a load of 3 to 1 on an incline of 1 in 30 at 9 miles an hour, which was a performance that had never, he thought, been beaten, if equalled, by any tender engine at home or abroad."
Wow! Indeed, by his measurement, the engines produced 25 hp per sq ft of grate and 8 hp per ton at 9 mph; 12 mph produced even better rsults. "...and those engines were capable, as an every-day duty, of taking 150 tons up the 1 in 30 inclines at a speed of 10 to 12 miles an hour."
Other observers and operators shared Burnett's high regard for this design, although no design can fail to be improved on. In the case of the B (205), it was the introduction of Belpaire-firebox boilers beginning in 1902. This vessel contained 241 1 3/4" tubes, which increased tube heating surface area to 1,192 sq ft (109.66 sq m) and overall EHS to 1,200 sq ft (119.5 sq m). Although the firebox's length increased by 6" and its width grew by 7 1/4", the grate area was said to have remained the same (these may be outside dimensions).. Weight increased by about 2 short tons.
In 1923, two of the class were superheated; see Locobase 15980.
Much of the class was scrapped in the 1930s, while a few hung on, the last being retired in 1962.
John Forsythe (Archive Officer, Transport House), Steam Locomotive Data, Public Transport Commission of NSW [New South Wales], July 1974, p. 73, archived at [], last accessed 12 March 2015. (Many thanks to Brett Fitzpatrick for his 11 March 2015 email supplying the link to the CoalsToNewcastle website.)
The NSWGR rebuilt these engines in the early 20th Century with the ever-more-popular Belpaire boiler. It had more tubes of a smaller diameter and slightly more firebox area that increased evaporative heating surface area by 163 sq ft (15.15 sq m).
John Forsythe (Archive Officer, Transport House), Steam Locomotive Data, Public Transport Commission of NSW [New South Wales], July 1974, p. 73, archived at [], last accessed 12 March 2015. (Many thanks to Brett Fitzpatrick for his 11 March 2015 email supplying the link to the CoalsToNewcastle website.)
These repeated the principal dimensions of the Beyer, Peacock engines of 10 years earlier, but weighed more.
Data from [] . Baldwin Locomotive Works Specification for Engines, as digitized by the DeGolyer Library of Southern Methodist University Volume 12, p. 89. John Forsythe (Archive Officer, Transport House), Steam Locomotive Data, Public Transport Commission of NSW [New South Wales], July 1974, p. 57, archived at [], last accessed 12 March 2015. (Many thanks to Brett Fitzpatrick for his 11March 2015 email supplying the link to the CoalsToNewcastle website.) Works numbers were 7387-7398 in July 1884.
Chris Drymalik notes that one engine of the class (Baldwin works #7388 - F 55) was transferred to the Commonwealth Railways. It was found to be in such poor condition, however, that it was retired after one year.
Data from "Mogul Engine, New South Wales Government Railways", Locomotive Magazine, Volume XXIII [23] (15 March 1917), p. 42; and "Rebuilt 2-6-0 Locomotive, New South Wales Government Railways", Locomotive Magazine, Volume XXV [25] (15 March 1919), p. 34. Dubs works numbers were 2629-2653 in 1890.
Locobase 15981 shows a class of Dubs-built 2-6-0s from 1890 that offer the closest match to the locomotive that LM coyly described as having been "designed some years back" and built by the NSWGR's own shops. In fact, says the 1919 LM report, the locomotive had RE-built in the Eveleigh Works. Its round-topped boiler was replaced by a one fitted with a Belpaire firebox. Inside the boiler, the original 234 tube layout, which had arranged in vertical rows, was replaced by 254 tubes in horizontal rows, thus gaining an additional 54 sq ft in heating surface area. Other changes included raising the cab was raised and extendng its roof to the rear, and a straight capped stack.
The 1917 LM report said that that one of these Moguls could pull a 230 ton train up a 1 in 40 (2 1/2%) grade at 10 mph (16 kph), 350 tons up a 1 in 60 (1.67%), 395 tons up 1 in 75(1.33%) at 12 mph (19 kph) , and 430 tons up 1 in 100 (1%) at 15 mph (26 kph).
When the NSWGR renumbered the class, the result, in order of the original block of numbers, was 60-65, 75-78, 388-390, 392-393, 66 407-410, and 55-58.
Some data from OS Nock (RWC II, Pl 126). See also John Forsythe (Archive Officer, Transport House), Steam Locomotive Data, Public Transport Commission of NSW [New South Wales], July 1974, p. 74, archived at [], last accessed 12 March 2015. (Many thanks to Brett Fitzpatrick for his 11March 2015 email supplying the link to the CoalsToNewcastle website.)
Having fitted a Belpaire boiler to the original B-205 design (Locobase 2406), the NSWGR installed a superheater to two of the engines several years later. That these were the only two suggests that the railway didn't find much improvement on the very good basic design.
Much of the class was scrapped in the 1930s, while a few hung on, the last being retired in 1962.
Principal Dimensions by Steve Llanso of Middle Run Media | |||||
---|---|---|---|---|---|
Class | B(205)/Z25 | B/Z24 | B/Z24 | K-294 | Z22 |
Locobase ID | 2406 | 2405 | 15981 | 3326 | 20577 |
Railroad | New South Wales | New South Wales | New South Wales | New South Wales | New South Wales |
Country | Australia | Australia | Australia | Australia | Australia |
Whyte | 2-6-0 | 2-6-0 | 2-6-0 | 2-6-0 | 2-6-0 |
Number in Class | 70 | 25 | 25 | 10 | 25 |
Road Numbers | 2501-2570 | 2401-2425 | 2401-2425 | 35-42, 44-45 / 294-303 / 1011-1019 | 458-482/see comments |
Gauge | Std | Std | Std | Std | Std |
Number Built | 70 | 25 | 25 | 10 | 25 |
Builder | Beyer, Peacock | NSWGR | Dubs & Co | Burnham, Parry, Williams & Co | Dnbs & Co |
Year | 1881 | 1917 | 1891 | 1884 | 1890 |
Valve Gear | Stephenson | Stephenson | Stephenson | Stephenson | Stephenson |
Locomotive Length and Weight | |||||
Driver Wheelbase (ft / m) | 11 / 3.35 | 11 | 11 / 3.35 | 14.75 | 11 / 3.35 |
Engine Wheelbase (ft / m) | 19 / 5.79 | 19 | 19 / 5.79 | 22.75 | 19 / 5.79 |
Ratio of driving wheelbase to overall engine wheelbase | 0.58 | 0.58 | 0.58 | 0.65 | 0.58 |
Overall Wheelbase (engine & tender) (ft / m) | 39.33 / 11.99 | 41.77 | 41.77 / 12.73 | 53.54 / 16.32 | |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 29,666 / 13,456 | 31,584 | 30,688 / 13,920 | 28,392 / 12,878 | 30,352 / 13,767 |
Weight on Drivers (lbs / kg) | 81,396 / 36,921 | 88,256 | 85,932 / 38,978 | 70,000 | 84,448 / 38,305 |
Engine Weight (lbs / kg) | 96,264 / 43,665 | 103,488 | 102,816 / 46,637 | 84,000 | 104,160 / 47,246 |
Tender Loaded Weight (lbs / kg) | 58,576 / 26,570 | 67,200 | 67,200 / 30,481 | 67,200 / 30,481 | |
Total Engine and Tender Weight (lbs / kg) | 154,840 / 70,235 | 170,688 | 170,016 / 77,118 | 171,360 / 77,727 | |
Tender Water Capacity (gals / ML) | 2400 / 9.09 | 3000 | 3000 / 11.36 | 2300 / 8.71 | 3000 / 11.36 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4.95 / 5 | 4.95 | 4.95 / 5 | 6 / 6 | 5.23 / 5 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 45 / 22.50 | 49 / 24.50 | 48 / 24 | 39 / 19.50 | 47 / 23.50 |
Geometry Relating to Tractive Effort | |||||
Driver Diameter (in / mm) | 48 / 1219 | 48 / 1219 | 48 / 1219 | 60.50 / 1219 | 48 / 1219 |
Boiler Pressure (psi / kPa) | 140 / 970 | 140 / 970 | 140 / 970 | 140 / 970 | 160 / 1100 |
High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 26" / 457x660 | 18" x 26" / 457x660 | 18" x 26" / 457x660 | 18" x 26" / 483x610 | 18" x 26" / 457x660 |
Tractive Effort (lbs / kg) | 20,885 / 9473.29 | 20,885 / 9473.29 | 20,885 / 9473.29 | 16,570 / 7516.03 | 23,868 / 10826.36 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.90 | 4.23 | 4.11 | 4.22 | 3.54 |
Heating Ability | |||||
Tubes (number - dia) (in / mm) | 241 - 1.875" / 0 | 189 - 2" / 51 | 207 - 2" / 0 | ||
Flues (number - dia) (in / mm) | |||||
Flue/Tube length (ft / m) | 10.58 / 3.22 | 11.50 | 10.50 / 3.20 | 11.33 | |
Firebox Area (sq ft / m2) | 94 / 8.73 | 104 | 100 / 9.29 | 105 / 9.76 | 105 / 9.75 |
Grate Area (sq ft / m2) | 21 / 1.95 | 21 / 1.95 | 21 / 1.95 | 17 / 1.58 | 21 / 1.95 |
Evaporative Heating Surface (sq ft / m2) | 1144 / 106.28 | 1408 / 130.86 | 1345 / 124.95 | 1299 / 120.72 | 1350 / 125.42 |
Superheating Surface (sq ft / m2) | |||||
Combined Heating Surface (sq ft / m2) | 1144 / 106.28 | 1408 / 130.86 | 1345 / 124.95 | 1299 / 120.72 | 1350 / 125.42 |
Evaporative Heating Surface/Cylinder Volume | 149.39 | 183.87 | 175.64 | 169.63 | 176.29 |
Computations Relating to Power Output (More Information) | |||||
Robert LeMassena's Power Computation | 2940 | 2940 | 2940 | 2380 | 3360 |
Same as above plus superheater percentage | 2940 | 2940 | 2940 | 2380 | 3360 |
Same as above but substitute firebox area for grate area | 13,160 | 14,560 | 14,000 | 14,700 | 16,800 |
Power L1 | 2361 | 2820 | 2698 | 3363 | 3134 |
Power MT | 191.84 | 211.33 | 207.65 | 317.75 | 245.45 |
Principal Dimensions by Steve Llanso of Middle Run Media | |
---|---|
Class | Z25 - superheated |
Locobase ID | 15980 |
Railroad | New South Wales |
Country | Australia |
Whyte | 2-6-0 |
Number in Class | 2 |
Road Numbers | |
Gauge | Std |
Number Built | |
Builder | NSWGR |
Year | 1923 |
Valve Gear | Stephenson |
Locomotive Length and Weight | |
Driver Wheelbase (ft / m) | 11 / 3.35 |
Engine Wheelbase (ft / m) | 19 / 5.79 |
Ratio of driving wheelbase to overall engine wheelbase | 0.58 |
Overall Wheelbase (engine & tender) (ft / m) | 39.33 / 11.99 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 31,584 / 14,326 |
Weight on Drivers (lbs / kg) | 88,456 / 40,123 |
Engine Weight (lbs / kg) | 106,288 / 48,211 |
Tender Loaded Weight (lbs / kg) | 58,576 / 26,570 |
Total Engine and Tender Weight (lbs / kg) | 164,864 / 74,781 |
Tender Water Capacity (gals / ML) | 2400 / 9.09 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 5 / 5 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 49 / 24.50 |
Geometry Relating to Tractive Effort | |
Driver Diameter (in / mm) | 48.50 / 1232 |
Boiler Pressure (psi / kPa) | 140 / 970 |
High Pressure Cylinders (dia x stroke) (in / mm) | 18.6" x 26" / 472x660 |
Tractive Effort (lbs / kg) | 22,070 / 10010.80 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.01 |
Heating Ability | |
Tubes (number - dia) (in / mm) | 100 - 1.875" / 48 |
Flues (number - dia) (in / mm) | 21 - 5" / 127 |
Flue/Tube length (ft / m) | 10.58 / 3.22 |
Firebox Area (sq ft / m2) | 107 / 9.94 |
Grate Area (sq ft / m2) | 21 / 1.95 |
Evaporative Heating Surface (sq ft / m2) | 941 / 87.42 |
Superheating Surface (sq ft / m2) | 227 / 21.09 |
Combined Heating Surface (sq ft / m2) | 1168 / 108.51 |
Evaporative Heating Surface/Cylinder Volume | 115.08 |
Computations Relating to Power Output (More Information) | |
Robert LeMassena's Power Computation | 2940 |
Same as above plus superheater percentage | 3499 |
Same as above but substitute firebox area for grate area | 17,826 |
Power L1 | 4870 |
Power MT | 364.13 |