Tasmanian Government Railways M class (1952)

Tasmanian Government Railways M class

M5 at the Tasmanian Transport Museum

Type and origin Power type Steam Builder Robert Stephenson and Hawthorns Serial number 7421-7430 Build date 1952 Total produced 10 Rebuilder Tasmanian Government Railways, Inveresk Rebuild date 1957 Number rebuilt 4 (MA class)

Specifications Configuration 4-6-2 Gauge 1,067 mm (3 ft 6 in) Leading dia. 2 ft 2.5 in (0.673 m) Driver dia. M: 4 ft 7 in (1,397 mm) MA: M: 4 ft 0 in (1,219 mm) Trailing dia. 2 ft 4 ^1⁄2 in (0.724 m) Length 59 ft 2 ^3⁄4 in (18.053 m) Axle load Loco: 10.20 long tons (10.4 t) Tender: 10.60 long tons (10.8 t) Adhesive weight 37.25 long tons (37.8 t) Loco weight 54.20 long tons (55.1 t) Tender weight 42.40 long tons (43.1 t) Fuel type Coal Fuel capacity 6 long tons (6.1 t) Water cap 4,000 imp gal (18,184.4 L) Firebox:  • Firegrate area 23.1 sq ft (2.146 m^2) Boiler pressure 180 lbf/in^2 (1.24 MPa) Heating surface:  • Tubes 601 sq ft (55.8 m^2)  • Flues 371 sq ft (34.5 m^2)  • Firebox 371 sq ft (34.5 m^2) Superheater: ​  • Type 18 element  • Heating area 371 sq ft (34.5 m^2) Cylinders 2 outside Cylinder size 16 in × 24 in (406 mm × 610 mm)

Performance figures Tractive effort 27,090 lbf (120.50 kN) Factor of adh. 3.98

Career Operators Tasmanian Government Railways Numbers M1-M10 Disposition all preserved

The Tasmanian Government Railways M class was a class of 4-6-2 steam locomotives operated by the Tasmanian Government Railways.

History

On 12 March 1952, the Tasmanian Government Railways (TGR) took delivery of 10 M class branch line locomotives from Robert Stephenson and Hawthorns, Newcastle-upon-Tyne. The locomotives were similar to the Indian Railways YB class.^[1][2]

They were allocated to operate on the North-Eastern and Western lines. However with the TGR having already commenced dieselisation with the X class, some of the lines intended for M class operation had already been converted. Hence in 1957, four were fitted with smaller driving wheels recovered from withdrawn Australian Standard Garratts enabling them to operate heavier trains over the steeply graded North-Eastern line.^[1][3][4]

As they fell due for overhaul, they were withdrawn from 1960 with the last removed from traffic in 1972.^[1]

Preservation

All members of the class have been preserved to an extent, with four locomotives seeing further use on heritage trains.

Original number	Builder's number	Final number	Preservation
M1	7421	MA2	Don River Railway, Devonport[5]
M2	7422	MA4	Don River Railway, Devonport[6]
M3	7423	M3	Don River Railway, Devonport[7]
M4	7424	M4	Don River Railway, Devonport[8]
M5	7425	M5	Tasmanian Transport Museum, Glenorchy[9]
M6	7426	MA3	Public park, Margate[10][11]
M7	7427	M1	Derwent Valley Railway[12]
M8	7428	MA1	Derwent Valley Railway[13]
M9	7429	M6	Bellarine Railway, Queenscliff, Victoria[14]
M10	7430	M2	Tanfield Railway, England[15]

Namesake

The M class designation was previously used by the M class, the last of which was withdrawn in 1931.

References

1. Oberg, Leon (2010). Locomotives of Australia 1850s-2010. Dural: Rosenberg Publishing. p. 257/258. ISBN 9781921719011.
2. "Steam Locomotives of the Tasmanian Government Railways and its Constituents" Australian Railway History issue 917 March 2014 page 16
3. Turner, Jim (1997). Australian Steam Locomotives 1896-1958. Kenthurst: Kangaroo Press. p. 159. ISBN 086417778X.
4. M & MA Class Rail Tasmania
5. MA2 Australian Steam
6. MA4 Australian Steam
7. M3 Australian Steam
8. M4 Australian Steam
9. M5 Australian Steam
10. MA3 Australian Steam
11. The Margate Train About Australia
12. M1 Australian Steam
13. MA1 Australian Steam
14. M6 Australian Steam
15. M2 Australian Steam