WAGR D Class

WAGR D class
D class with a set of suburban coaches, Perth Yard, 1926
Type and origin Power type Steam Builder North British Locomotive Company Serial number 19709-19728 Build date 1912 Total produced 20
Specifications Configuration: ​  • Whyte 4-6-4T Gauge 3 ft 6 in (1,067 mm) Driver dia. 4 ft 6 in (1,372 mm) Length 42 ft 6 in (12.95 m) Loco weight As built: 68 long tons 5 cwt (152,900 lb or 69.3 t) Superheated: 70 long tons 0 cwt (156,800 lb or 71.1 t) Fuel type Coal Fuel capacity 4 long tons 0 cwt (9,000 lb or 4.1 t) Water cap 1,600 imp gal (7,300 l; 1,900 US gal) Firebox:  • Firegrate area 18.63 sq ft (1.731 m2) Boiler pressure As built: 175 lbf/in2 (1.21 MPa) Superheated: 160 lbf/in2 (1.10 MPa) Cylinder size As built: 17 in × 23 in (432 mm × 584 mm) Superheated: 18 in × 23 in (457 mm × 584 mm)
Performance figures Tractive effort As built: 17,233 lbf (76.66 kN) Superheated: 18,768 lbf (83.48 kN) Factor of adh. As built: 4.7 Superheated: 4.6
Career Operators Western Australian Government Railways Numbers D368-D387 Disposition all scrapped

The WAGR D class was a class of 4-6-4T tank locomotive operated by the Western Australian Government Railways (WAGR) between 1912 and 1964.

In 1911 the WAGR placed an order with the North British Locomotive Company for twenty 4-6-4T locomotives to haul suburban passenger services in Perth. All entered service between June and September 1912. Commencing in 1932, all bar D386 were rebuilt as the Ds class with superheated boilers. In 1935, D377 was fitted with larger side tanks increasing its water capacity by 210 gallons, these were removed in May 1959. With the arrival of the ADH class diesel multiple units in 1953, withdrawals commenced with the last withdrawn in November 1965.

The D class was also the basis for the later Dm and Dd classes of tank engine, which continued this role until the end of steam.

The numbers and periods in service of each member of the D class were as follows:

The D class designation was previously used for the D class locomotive that was withdrawn in 1903. It was reused in the 1970s when the D class diesel locomotives entered service.