Victorian Railways A2 class

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Victorian Railways A2 Class (Walschaerts)
A2 986.jpg
VR photograph of A2 986 in 1916, in original form
Type and origin
Power type steam
Builder VR Newport, Ballarat & Bendigo Workshops
Total produced 185
Specifications
Configuration 4-6-0
Gauge 5 ft 3 in (1,600 mm)
Driver diameter 73 in (1.854 m)
Length 63 ft 3 34 in (19.30 m)
Axle load 17 long tons 10 cwt (39,200 lb or 17.8 t)
Weight on drivers 52 long tons 2 cwt (116,700 lb or 52.9 t)
Locomotive and tender
combined weight
121 long tons 7 cwt (271,800 lb or 123.3 t)
Tender capacity (after conversion to oil firing)
1,500 imp gal (6,800 l; 1,800 US gal) oil, 4,700 imp gal (21,000 l; 5,600 US gal) water
Boiler pressure 185 psi (1,276 kPa)
Firegrate area 29 sq ft (2.7 m2)
Heating surface:
– Total
2,040 sq ft (190 m2)
Cylinders Two
Cylinder size 22 in × 26 in (559 mm × 660 mm)
Valve gear Stephenson (125)
Walschaerts (60)
Performance figures
Tractive effort 27,480 lbf (122.24 kN) at 85% boiler pressure
Career
First run 1907
Last run 1963

The A2 class was an express passenger locomotive that ran on Victorian Railways from 1907 to 1963. A highly successful design entirely the work of Victorian Railways' own design office, its long service life was repeatedly extended as economic depression and war delayed the introduction of more modern and powerful replacement locomotives.

History[edit]

The introduction of the A2 class marked a turning point in Victorian Railways locomotive design, as it was entirely designed by VR engineers of the newly established Locomotive Design Section and the entire class built in-house at Victorian Railways workshops.[1]

Production[edit]

Based on the success[2] of the prototype A2 572, a total of 125 Stephenson valve gear A2 locomotives were built between 1907 and 1915. The design was then altered to incorporate larger diameter cylinders, a higher pressure boiler and Walschaerts valve gear, and a further 60 locomotives of this design were produced between 1915 and 1922.[1]

Regular service[edit]

For over forty years, the A2 was the main express passenger locomotive on the VR, hauling intrastate and interstate services. With a maximum permitted speed of 70 miles per hour (112.7 km/h)[3] the A2 was instrumental in the acceleration of timetables on many lines in the years following its introduction. They famously ran the Geelong Flier service[4] (the first "named" train in Victoria)[5] slashing journey times between Melbourne and Geelong from 90 minutes[6] to 63[7] and finally 55 minutes,[8] a time not significantly improved upon until the introduction of 160 km/h Regional Fast Rail services in 2006.[9]

A2s were also used to haul a number of special services, such as the Royal Trains for the Prince of Wales' and the Duke of York's Australian tours in 1920[10] and 1927 respectively. Towards the end of their lives, A2 995 and 996 also had the distinction of hauling the last broad gauge Spirit of Progress service into Melbourne on 16 April 1962.[11]

With their comparatively high tractive effort (the Walschaerts A2 had a higher nominal tractive effort than any other VR locomotive, regardless of type, until the introduction of the C class 2-8-0 of 1918) they also saw widespread use as a fast goods locomotive, particularly in their later life.[1] It was reported as normal practice as early as the 1920s for A2 class locomotives requiring adjustment to axle boxes (axleboxes) and other moving parts to be swapped from passenger to lower-speed freight service to extract greater work from them between overhauls.[12]

In 1933, two A2 class locomotives set a haulage record for Victorian Railways when they took a 75 truck 1,598-long-ton (1,624 t) wheat train from Benalla to Seymour.[13]

Although initially limited to principle mainlines due to their comparatively heavy axle load, gradual upgrades to secondary lines saw the route availability of the class expand, together with the range of services they hauled.[14]

In 1928, the A2 was replaced on the principal North-eastern line Sydney Limited and Albury Express services by the considerably more powerful three-cylinder S class Pacifics. However, new locomotive development ground to a halt during the 1930s[15] as the Great Depression severely affected both VR traffic volumes and operating revenues, and the A2 continued as the main express passenger power on all other VR mainlines.

Design Improvements[edit]

The majority of A2 locomotives were originally built with saturated steam boilers. The class were gradually fitted with superheaters, and to differentiate between the two variants the saturated steam locomotives were renumbered as A1 class, each being reclassified as A2 class again when fitted with a superheater. The last of the A1 class, No. 808, was converted in October 1949.

Experiments were conducted in 1923-4 with A2 800 using Pulverised Brown Coal (PBC) burning equipment, however the experiment was discontinued and the locomotive returned to black coal operation.[16]

The A2 class, along with other post-1900 VR steam locomotive designs, was equipped with electric lighting from 1926 onwards. Automatic Staff Exchange equipment to allow non-stop high-speed running between track sections was also fitted from 1926 onwards.[17]

Modified front end[edit]

In 1933, C class heavy goods locomotive C 5 was equipped with a new front end, based on the Association of American Railroads (AAR) design of self-cleaning smokebox, to improve steaming qualities. The results were very promising, and in 1934 A2 998 was selected for a series of further tests aimed at further front end improvement, conducted under the direction of VR Rolling Stock branch engineer, Edgar Brownbill.[18]

Diagram of A2 locomotive boiler, firebox and smokebox following Modified Front End improvements

Experiments based on the work of Dr Wagner of the Deutsche Reichsbahn and E. C. Young of the University of Illinois were conducted, with final modifications to the A2 locomotive including:[18]

  • Revision of exhaust nozzle and chimney position and diameter using Wagner's recommended ratios, with a larger 23 in (584.2 mm) diameter funnel and 6 in (152.4 mm) diameter, low exhaust nozzle replacing the original 18 12 in (469.9 mm) diameter narrow flanged chimney and 5 12 in (139.7 mm) diameter, high exhaust nozzle
  • Revision to the firebox grate with fitting of a "rosebud" type grate with reduced air openings to improve fire stability under heavy load and give better firing qualities
  • Replacement of full length 1 38 in (34.92 mm) return bend superheater elements with 8 ft 6 in (2.591 m) long 1 12 in (38.10 mm) elements

The sum result of these changes was a significant improvement in power and available tractive effort. Maximum drawbar horsepower increased some 40% from 860 hp (640 kW) at 26 mph (42 km/h) to 1,230 hp (920 kW) at 32 mph (51 km/h).[18] The improvement was such that the VR was able to further accelerate services hauled by the A2, with the steeply graded 100 34 mi (162.1 km) Melbourne to Bendigo express running time being cut from 162 to 145 minutes, and literally hours being cut from the schedule of the Melbourne to Adelaide Overland express.[19]

Modified Front End was an extremely cost effective improvement given that it allowed the VR to defer new locomotive construction through improvements to existing locomotives that at the time cost just £140 ($280) per locomotive. It was so successful that not only was the entire A2 fleet converted during 1936–39, but also the C, K, N, S and X class locomotive fleets, and its principles were also incorporated into the design of all subsequent steam locomotives built for VR.[18][20]

Other changes[edit]

In 1935 an experimental A.C.F.I. (Accessoires pour les Chemins de Fer et l'Industrie) feedwater heater was fitted to A2 973. However, there was not sufficient improvement in efficiency for the equipment to be fitted to other locomotives and it was removed twelve years later.[14]

With the reduced exhaust blast resulting from the revised smokebox, smoke deflectors were fitted to prevent drifting smoke from obscuring visibility.[21]

In the years following World War II, problems with the quality and availability of coal supplies caused VR to order the conversion of all 60 Walschaerts A2s to oil firing.[1]

Late in their life, some of the A2s also received Boxpok driving wheels[14] as their conventional spoked wheels began to suffer fatigue cracks with age and mileage.[22]

Later Years[edit]

In 1939, by which time most of the class was already over twenty-five years old, World War II broke out. The massive increase in traffic on the VR the war effort brought saw these ageing locomotives subjected to a punishing regime of heavy utilisation and minimal maintenance.[15]

Stephenson A2 884 (right) dwarfed by H 220 (left), the locomotive intended to replace the A2 on Overland services

With VR's locomotive workshops switched to production of armaments and all available manpower given to the war effort, plans to eliminate the double-headed A2 operations on Melbourne-Adelaide passenger services with the introduction of more powerful H class 4-8-4 locomotives and additional S class locomotives did not come to fruition. The extra S class locomotives were never built and the line to Adelaide did not receive the necessary upgrades to take the weight of the H class.[23]

The A2's principal express passenger role continued into the postwar years as the VR, struggling with a backlog of repairs and limited capital expenditure, deferred new passenger locomotive construction. It was not until March 1946 when the first of the class, A2 878, was withdrawn from service.[14]

In 1951, when the first of 70 new R class 4-6-4 express passenger locomotives were introduced, the A2 was finally superseded. In 1953, no fewer than 53 A2s went to scrap, followed by 36 more in 1954.[14] However, many of the class (particularly the later Walschaerts variants) continued on in secondary roles such as branch-line passenger and goods services and a number lasted into the 1960s. Their last regular mainline duty was hauling services between Flinders Street Station and Leongatha, on the South Gippsland line. The last in service, A2 986, was withdrawn on 2 December 1963, exactly 56 years after the original A2 572 entered service.[14][24]

Accidents[edit]

Some A2 locomotives were unfortunate enough to be involved in major accidents:

  • At 2:58am on 7 September 1951, the westbound and eastbound Overland expresses, both hauled by double-heading A2s, collided head-on at Serviceton.[25][26] All four locomotives were written off; three were so badly damaged they were scrapped on site.
  • Australia's worst level crossing accident occurred on 8 May 1943, when A2 863 collided with a bus carrying troops at Wodonga.[5] 25 people were killed.[27]

Preservation[edit]

Preserved A2 995, circa 1990

Only one of the original batch of 125 Stephenson A2 locomotives survives; 1913-built A2 884 is today preserved at the ARHS North Williamstown Railway Museum, along with (Walschaerts) A2 995. The museum notes that A2 884 ran a total 1,002,624 miles (1,613,567 km) and A2 995 a total 1,270,404 miles (2,044,517 km) during their service lives.[28]

A2 996 is preserved in Victorian regional city of Echuca and A2 964 is preserved in the Melbourne suburb of Reservoir.

A2 986 is currently being restored to full working order by Steamrail Victoria.

References[edit]

  1. ^ a b c d Pearce et al., p. 12
  2. ^ "steamlocomotive.com Locobase #2385". Archived from the original on 2007-09-27. Retrieved 2006-10-02. 
  3. ^ Pearce et al., p. 21
  4. ^ "VPRS 12800/P1 H 1667 - PUBLIC RECORD OFFICE VICTORIA - A2 CLASS STEAM LOCOMOTIVE No.906 GEELONG FLIER FIRST TRIP". Public Record Office Victoria. Retrieved 2008-05-04. 
  5. ^ a b "VR History". victorianrailways.net. Retrieved 2008-05-04. 
  6. ^ "circa 1905 Bradshaw's guide, page 24". Retrieved 2008-04-25. 
  7. ^ "1928 Country Passenger timetables". Retrieved 2008-04-25. 
  8. ^ "The Pride of the Diesel Fleet". The Victorian Railways Newsletter. July 1950. Retrieved 2008-04-25. 
  9. ^ "GEELONG FAST RAIL CONSTRUCTION ON TRACK" (Press release). Department of Premier and Cabinet, Victoria. 2004-02-04. Retrieved 2008-05-04. The express travel time will be 45 minutes, a saving of at least six minutes over the existing express services. 
  10. ^ Public Record Office Victoria Series VPRS 12800/P1 Item H 1027 retrieved 2 October 2006
  11. ^ "Victorian Railways, Museum Victoria, Australia: Spirit of Progress A2-class steam locomotive No. 995, 16 April 1962". http://www.prov.vic.gov.au. Retrieved 2008-04-25. 
  12. ^ "NEWPORT WORKSHOPS.". The Argus (Melbourne, Vic. : 1848–1956) (Melbourne, Vic.: National Library of Australia). 4 January 1922. p. 14. Retrieved 3 January 2013. 
  13. ^ "HUGE WHEAT HAUL BY TRAIN.". The Horsham Times (Vic. : 1882–1954) (Vic.: National Library of Australia). 6 June 1933. p. 4. Retrieved 3 January 2013. 
  14. ^ a b c d e f Oberg, Leon (1984). Locomotives Of Australia 1850's - 1980's. NSW: Reed Books. p. 96. ISBN 0-7301-0005-7. 
  15. ^ a b "AHRS Railway Museum: History 1900–1950". Australian Railway Historical Society. Retrieved 2006-10-02. 
  16. ^ Pulverised Brown Coal Fuel for Steam Locomotives Buckland, John L. Australian Railway Historical Society Bulletin, July 1972 pp145-161
  17. ^ "A2 locos". victorianrailways.net. Retrieved 2009-06-14. 
  18. ^ a b c d Abbott, R.L. (November 1971). "Steam Locomotive Performance - the Modified Front End". ARHS "Bulletin" (Australian Railway Historical Society) (409). 
  19. ^ Lee, Robert. The Railways of Victoria 1854–2004. Melbourne University Publishing Ltd. p. 157. ISBN 978-0-522-85134-2. 
  20. ^ "100 defining aspects of Australian railways" (PDF). Australian Railway Historical Society. Retrieved 2008-05-10. (H220) had... benefit of Brownbill's modified front-end experience 
  21. ^ Stevens, Colin (December 2000). Stack Talk (Steamrail Victoria) 11 (3): p. 10. 
  22. ^ Carlisle, R M & Abbott, R L (1985). Hudson Power. ARHS. pp. 30–31. ISBN 0-85849-028-5. 
  23. ^ Pearce et al., p. 19
  24. ^ "steamtrainartist.com Victorian Railways 'A2' CLASS 4-6-0". Archived from the original on 2006-03-27. Retrieved 2006-10-02. 
  25. ^ "Auditor General's Department EMA Disasters Database". Archived from the original on 2007-09-26. Retrieved 2006-10-02. 
  26. ^ Railpage discussion retrieved 2 October 2006
  27. ^ "Australian Defence Department: On This Day - 8 May". Archived from the original on 2007-09-03. Retrieved 2006-10-02. 
  28. ^ Railway Museum (guide to exhibits). ARHS. (available as of) 2008. p. 30.  Check date values in: |date= (help)

External links[edit]