New South Wales AD60 class locomotive

New South Wales AD60 class

6012 at the top of Cowan Bank

Type and origin Power type Steam Builder Beyer, Peacock and Company Manchester Serial number 7473–7497, 7528–7549 Build date 1952–1954, 1956 Total produced 42 (plus 5 as spares)

Specifications Configuration: ​  • Whyte 4-8-4+4-8-4 Gauge 4 ft 8 1⁄2 in (1,435 mm) Driver dia. 4 ft 7 in (1.397 m) Adhesive weight 282,000 lb (128,000 kg) later 317,000 lb (144,000 kg) Loco weight 562,000 lb (255,000 kg) later 582,000 lb (264,000 kg) Fuel type Coal Fuel capacity 14 long tons (14.2 t; 15.7 short tons) later 18 long tons (18.3 t; 20.2 short tons) Firebox:  • Firegrate area 65 sq ft (6.0 m2) Boiler pressure 200 psi (1.38 MPa) Heating surface 3,030 sq ft (281 m2) Superheater: ​  • Heating area 750 sq ft (70 m2) Cylinders Four Cylinder size 19.25 in × 26 in (489 mm × 660 mm) later 19.875 in × 26 in (505 mm × 660 mm) Valve gear Walschaerts

Performance figures Tractive effort 59,560 lbf (264.9 kN) later 63,490 lbf (282.4 kN) Factor of adh. 4.73 or 4.99

Career Operators New South Wales Government Railways Class AD60 Number in class 42 Numbers 6001–6042 First run July 1952 Last run March 1973 (in service) Preserved 6029, 6039, 6040, 6042 Disposition 4 preserved, 38 scrapped

The AD60 class were Beyer-Garratt patent articulated four-cylinder, simple, non-condensing, coal-fired superheated, 4-8-4+4-8-4 heavy goods steam locomotives built by Beyer, Peacock and Company for the New South Wales Government Railways in Australia.

The AD60 Class 4-8-4+4-8-4 Beyer-Garratt patent consists of a boiler carried on a separate frame in the centre of the locomotive and supported by the frames of the two engines, one at each end. The locomotive thus consists of three parts: a water tank, a fixed chassis supporting a boiler and a rear engine unit carrying a coal bunker and water tank. The standard gauge coupled axle loading of 16 long tons (16.3 t; 17.9 short tons) and able to negotiate 6-chain (120 m) curves.

The design incorporated the most modern technology to minimise maintenance and repairs, including:

This was the only type of Garratt locomotive to operate on the New South Wales Government Railways. Designed to a light axle load of only 16 long tons (16.3 t; 17.9 short tons), they were intended for hauling feeder branch-line services to the main lines where heavier main-line locomotives could continue with the load.

In 1949 twenty-five were initially ordered from Beyer, Peacock and Company, followed by a further twenty-five. Following a change of policy in favour of diesel traction, negotiations were entered into, in order to cancel the last part of the order. Forty-two complete locomotives were delivered, together with spare parts equating to approximately five further locomotives. The five sets of parts did not include engine unit frames. The cancellation contract stipulated that the NSWGR could not assemble the spare parts into complete locomotives without paying substantial royalties to Beyer- Peacock. The last three locomotives were cancelled completely and the assembly positions at the Gorton Works of Beyer - Peacock were sold to the South African Railways.

The locomotives were delivered in their five major component pieces: Front engine, rear engine, boiler-cab, rear bunker and front water tank. These five sub assemblies were built into a complete locomotive in NSW.