Australian Standard Garratt
| Australian Standard Garratt | |
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 Australian Standard Garratt No. 33 in the Museum of the Australian Railway Historical Society in North Williamstown, Victoria.
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| Numbering: | 1-33, 37, 38, 44-65 |
| Number: | 57 (+8 not completed) |
| Manufacturer: | see text |
| Year of construction (s): | 1943-1945 |
| Retirement: | 1945–1966 |
| Type : | (2'D1 ') (1'D2') h4 (Garratt) |
| Gauge : | 1067 mm ( cape track ) |
| Length over coupling: | 26,160 mm |
| Service mass: | 117.7 t |
| Friction mass: | 69 dd |
| Wheel set mass : | 8.6 t |
| Driving wheel diameter: | 1,219 mm |
| Cylinder diameter: | 368 mm |
| Piston stroke: | 610 mm |
| Boiler overpressure: | 137 N / cm² |
| Grate area: | 3.25 m² |
| Radiant heating surface: | 15.1 m² |
| Tubular heating surface: | 142.6 m² |
| Superheater area : | 29.2 m² |
| Water supply: | 19 m³ |
| Fuel supply: | 6 tons of coal |
| Train brake: | Compressed air or suction air brake |
The Australian Standard Garratts (ASG) were war locomotives of the Garratt design that were built during the Second World War for the Cape-gauge Australian railroad companies in Queensland , Western Australia and Tasmania . The hastily designed locomotives were considered a faulty design and some of them were taken out of service immediately after the war.
history
Especially the railways in Queensland were exposed to a heavy additional load because of the Pacific War ; compared to 1939, traffic had risen by 51% by 1942. Garratt locomotives were supposed to help cope with traffic, a type that had not been used by the Queensland Government Railways (QGR) until then. Beyer-Peacock was busy building other war Garratts, so the decision was made to build the necessary machines in Australia, especially since the Midland Junction workshops of West Australian Government Railways (WAGR) already had experience building Garratts collected ( class Msa ).
However, instead of starting from one of the existing Garratt designs, the chief engineer at WAGR constructed a completely new locomotive in just three months. Parts were supplied by more than 100 companies across Australia, and assembly was carried out in rail workshops in Midland, Newport, Victoria and Islington, South Australia, as well as at the private company Clyde Engineering .
The design flaws identified during construction were so serious that the Victorian Government Railways workshop in Newport refused to affix their nameplates to the locomotives built there. Only the forced situation of the war could induce the railway companies and the staff to use the locomotives.
After the war, many train drivers refused to use the ASG, partly because they were prone to derailments. Another problem was the fire door , the construction of which led to strong heat radiation in the driver's cab. A royal commission of inquiry was formed and as a result 36 major changes were made to the locomotives. Nevertheless, the QGR decided not to continue operating the series and instead ordered new Garratts from Beyer-Peacock.
Numbers and operators
A total of 65 Australian Standard Garratts were ordered, 57 of which were completed and 55 were put into service. Initially, 26 came to the WAGR, 23 to the QGR and 6 to the Tasmanian Government Railways (TGR).
The TGR took over six QGR locomotives after the war. The QGR gave another 3 machines to the private Emu Bay Railway . 6 locomotives were sold by WAGR to South Australian Railways (SAR) in 1951 , where they formed class 300 . They were a quick "emergency solution" for heavy coal and ore trains, because at the same time the SAR ordered 10 new Garratts of class 400 , which replaced the ASG in 1953/54.
Many ASG were scrapped as early as the 1950s. They were longest in service with the TGR (until 1957) and the Emu Bay Railway (until 1966), which is also located in Tasmania. In Victoria , a former WAGR machine was used at a cement works and was also in operation until 1966. This machine with the number 33 is the only Australian Standard Garratt to survive; it is now in the museum of the Australian Railway Historical Society in Williamstown North, a suburb of Melbourne .
technology
The Australian Standard Garratts had the wheel arrangement common to Garratts (2'D1 ') (1'D2'). In order to be able to drive through tight curves, the first and third coupling axles each had no wheel flanges , which led to frequent derailments, the greatest flaw in the design. The drive frames were built on sheet metal frames, the girders of the boiler bridge were provided with triangular cutouts to save weight.
The Belpaire boiler had no steam dome , only a manhole cover . Unusual for a war locomotive, which requires a simple design, were the continuous cladding of the boiler superstructures between the chimney and driver's cab, as well as the “streamlined” water tanks at both ends of the locomotive.
Depending on the area of application, there were differences in the clutches and in the braking system: In Tasmania and Western Australia, suction air brakes were used, Queensland and South Australia air brakes . The locomotives for Queensland and Tasmania received buffers and screw couplings, those for Western and South Australia central buffer couplings.
literature
- AE Durrant: Garratt locomotives of the world . Birkhäuser Verlag ISBN 3-7643-1481-8