Tasmanian Government Railways Z class

The Z class are a class of diesel locomotives built by English Electric Rocklea for the Tasmanian Government Railways in 1973. They were a development of the WAGR RA class and were the last of a line of very successful locomotives fitted with the English Electric 12CSVT Mk II engine.

Tasmanian Government Railways Z class
Type and origin Power type Diesel-electric Builder English Electric Rocklea Build date 1973 Total produced 4
Specifications Configuration: ​  • UIC Co-Co Gauge 1,067 mm (3 ft 6 in) Wheel diameter 3 ft 1 ^1⁄2 in (0.953 m) Wheelbase 42 ft 5 in (12.929 m) total, 11 ft 3 in (3.429 m) bogie Length 55 ft (16.764 m) over headstocks Width 9 ft 4 in (2.845 m) Height 12 ft 4 ^1⁄2 in (3.772 m) Axle load 16 long tons (16.3 t; 17.9 short tons) Loco weight 96 long tons (97.5 t; 107.5 short tons) Fuel type Diesel Fuel capacity 1,200 imp gal (5,500 L) Prime mover English Electric 12CSVT Mk II RPM range 450 - 850 rpm Engine type four stroke, four valves per cylinder Aspiration turbocharged, intercooled Generator EE822/16J Traction motors Six EE558 Cylinders 12 Vee Cylinder size 10 in × 12 in (254 mm × 305 mm) MU working 110V, stepless electro-pneumatic throttle Loco brake Air - straight and proportional control, dynamic Train brakes Vacuum, converted to air (1984-1985)
Performance figures Maximum speed 60 miles per hour (97 km/h) Power output 2,025 hp (1,510 kW) gross, 1,850 hp (1,380 kW) net Tractive effort: ​  • Continuous 54,000 lbf (240.2 kN) at 10.5 mph (20 km/h)
Career Operators Tasmanian Government Railways Number in class 4 Numbers Z1-Z4 First run June 1973 Current owner TasRail Disposition 4 stored

History

With the construction of a new line from Launceston to Bell Bay, Tasmanian Government Railways placed an order for four 1752 kW locomotives with English Electric. However, with the locomotive still under development, it was decided to purchase four 1380 kW locomotives that were an evolution of the Western Australian R class locomotives with a low nose profile and vacuum brakes. At 96 tons, they were considerably heavier than the previous heaviest locomotives on the network, the Y class at 58 tons, requiring significant upgrades to infrastructure.[1][2]

In March 1978 the Z class were included in the transfer of the Tasmanian Government Railways to Australian National. In 1984-1985 all had their vacuum brakes replaced with air brakes.[3]

In June 1998 all were renumbered as the 2110 class.[4]

All remained in service with TasRail until stored in May 2014 with the entry into service of the new TR class, new drivers having ceased training on these locos 8 months prior. Listed for disposal, they are as yet unsold.

Status table

Name	Original no	Current no	Owner	Status
Northern Progress	Z1	2110	TasRail	Stored
Bell Bay Pioneer	Z2	2111	TasRail	Stored
	Z3	2112	TasRail	Stored
	Z4	2113	TasRail	Stored

See also

• Former Tasmanian Government Railways locomotives
• Locomotives of the Tasmanian Government Railways/1950

References

1. Oberg, Leon (1984). Locomotives of Australia 1850s-1980s. Frenchs Forest: Reed Books. pp. 284–285. ISBN 0 730100 05 7.
2. Z Class Railpage
3. Z Class Rail Tasmania
4. "Tasrail Loco Renumbering" Railway Digest October 1998 page 36