Commonwealth Railways NM class

The Commonwealth Railways NM class locomotive is a class of 4-8-0 locomotives of the Commonwealth Railways, Australia. The class operated on 1,067 mm (3 ft 6 in) narrow gauge lines in South Australia and the Northern Territory.

Commonwealth Railways NM class
Preserved NM34 at the National Railway Museum in October 2010
Type and origin Power type Steam Builder Thompson & Co, Castlemaine Build date 1925-1927 Total produced 22
Specifications Configuration: ​  • Whyte 4-8-0 Gauge 1,067 mm (3 ft 6 in) Fuel type Coal Firebox: ​  • Grate area 18.5 sq ft (1.72 m2) Boiler pressure 160 psi (11 bar; 1,100 kPa) Cylinder size 17 in × 22 in (432 mm × 559 mm)
Performance figures Tractive effort 18,085 lbf (80.45 kN)
Career Operators Commonwealth Railways Numbers NM15-NM28 NM31-NM38 First run June 1925 Preserved NM25, NM34 Current owner National Railway Museum Pichi Richi Railway Disposition 2 preserved, 20 scrapped

History

Between June 1925 and December 1927, the Commonwealth Railways took delivery of 22 locomotives built to the same design as the Queensland Railways C17 class for use on the Central Australia Railway, but with larger tenders and vacuum rather than air brakes. All were built by Thompson & Co, Castlemaine.^[1][2]

The final locomotive was despatched to the North Australia Railway, returning south in September 1941.^[2]

Eighteen were converted to burn oil during the 1949 coal strike, being converted back to coal burning after the strike ended. All were withdrawn between 1954 and 1956 as the NSU diesel locomotives entered service.^[1]

Two have been preserved, NM25 in operational condition at the Pichi Richi Railway^[3] and NM34 at the National Railway Museum, Port Adelaide.^[4]