South Australian Railways 720 class

The South Australian Railways 720 class was a class of 2-8-4 steam locomotives operated by the South Australian Railways.

South Australian Railways 720 Class
724 at North Adelaide station in 1952
Type and origin
Power typeSteam
DesignerFred Shea
BuilderIslington Railway Workshops
Build date1930-1943
Total produced17
Specifications
Configuration:
​
 • Whyte2-8-4 1′D2′ 3′3′
Gauge1,600 mm (5 ft 3 in)
Leading dia.2 ft 9 in (838 mm)
Driver dia.4 ft 9 in (1,448 mm)
Trailing dia.3 ft 0 in (914 mm)
3 ft 6 in (1,067 mm)
Length83 ft 6 in (25.45 m)
Height13 ft 11+5⁄8 in (4,256.1 mm)
Axle load19.85 long tons 0 cwt (44,500 lb or 20.2 t)
Adhesive weight77.10 long tons 0 cwt (172,700 lb or 78.3 t)
Loco weight123.80 long tons 0 cwt (277,300 lb or 125.8 t)
Tender weight104.00 long tons 0 cwt (233,000 lb or 105.7 t)
Total weight227 long tons 4 cwt (508,900 lb or 230.8 t)
Fuel typeCoal
Oil
Fuel capacity17 long tons 0 cwt (38,100 lb or 17.3 t)
3,060 imp gal
(3,670 US gal; 13,900 L) oil (locos converted to oil burning only)
Water cap.9,000 imp gal
(11,000 US gal; 41,000 L)
9,400 imp gal
(11,300 US gal; 43,000 L) (when oil fired)
Firebox:
 • Firegrate area		59.5 sq ft (5.53 m2)
Boiler pressure215 psi (1,482 kPa)
Heating surface:
 • Tubes		2,615 sq ft (242.9 m2)
 • Firebox360 sq ft (33 m2)
Superheater:
​
 • Heating area751 sq ft (69.8 m2)
Cylinders2
Cylinder size22 in × 28 in (559 mm × 711 mm)
Valve gearWalschaerts valve gear
Valve typePiston
Performance figures
Tractive effort43,450 lbf (193.28 kN)
52,000 lbf (231.31 kN) with booster engine cut in
Factor of adh.4.0
Career
OperatorsSouth Australian Railways
Class720
Number in class17
Numbers720-736
First run26/11/1930
Withdrawn1958-1960
Scrapped1958-1963
DispositionAll scrapped

History

The 720 class were built by the South Australian Railways as an improved version of the 710 class locomotives. The initial order was for five locomotives. They were intended to operate on the lighter broad gauge lines, but after they began to spread rails, they were confined to the heavier lines. A further twelve were built between 1938 and 1943. The final twelve differed in having streamlined valances and boiler lagging tinwear. Coal shortages after World War II saw 14 converted to burn oil. All were later converted back to coal burners. The last were withdrawn in April 1960.[1][2]

Locomotive 720 at Islington Railway Workshops.

References
  1. 720 class Chris' Commonwealth Railways Information
  2. Oberg, Leon (1984). Locomotives of Australia 1850s-1980s. Frenchs Forest: Reed Books. p. 161. ISBN 0730100057.

Media related to South Australian Railways 720 class at Wikimedia Commons

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.