| Tasmanian Government Railways Y Class | |
|---|---|
| Power type | Diesel Electric |
| Builder | Tasmanian Government Railways Launceston Workshops |
| Serial number | Not Numbered |
| UIC classification | Bo-Bo |
| Gauge | 1067mm |
| Engine type | English Electric 6SRKT |
| Cylinders | in-line 6 |
| Cylinder size | 254×305 mm (10×12 in) |
| Top speed | 80 kilometres per hour (50 mph) |
| Power output | 597 kilowatts (800 hp) |
| Train brakes | Vacuum |
| Number in class | 8 |
| Number | Y1-Y8 |
| First run | 1961 |
| Preserved | 5 |
The Tasmanian Government Railways (TGR) built and ran 8 "Y" class diesel electric locomotives.
Contents |
Following the success of the 1952-vintage TGR X class main-line diesel-electric locomotives, the TGR were keen to add additional diesel locomotives to their fleet.
A repeat order of 'X' class engines may have been considered but was quickly discarded. After trying several manufacturers, the TGR settled on technology of the English Electric (EE) company, which had built the 'X' class engines. As a result, the plans EE submitted were quite similar to, and essentially a development of, the 'X' class, but slightly larger and more powerful.
When built, these engines were designated Y Class. Design-wise they are similar to the 'X' class - a long, hood unit with the cab at one end.
Construction started in the TGR Inveresk workshops in 1961, and three of the planned eight were completed relatively quickly. However, construction of the other five was slow, with the last not being delivered until 1972, by which time the design was obsolete.
They are fitted with an EE 6SRKT in-line six turbocharged diesel engine (which was also fitted in the 'X' class locomotives), but producing 825 horsepower (615 kW) at 850 rpm as compared to the 'X' class 660 hp (490 kW) at 750 rpm. They have a Bo-Bo wheel arrangement and end-platforms, making them visually similar to the older 'X' class engines. It is easy to confuse the two classes from a distance.
Like all TGR rolling stock of the time, they were fitted with hook couplers and vacuum brakes. With a light tractive weight of only 58 tonnes (one tonne heavier than the 'X' class), and a reasonably powerful engine of 825 horsepower (615 kW), gaining traction on long uphill grades was found to be difficult. They have a tendency to wheel-slip badly. Nevertheless they were considered successful.
When the TGR was taken over by Australian National (AN) in 1978, the decision was made to import a batch of second-hand Goodwin Alco '830' class Co- Co diesel-electric locomotives from South Australia, and some 2,000 hp (1,500 kW) GEC diesels from Queensland, rapidly making the 'X' and 'Y' class engines obsolete. Nevertheless, throughout the late 1970s and early 1980s all members of the 'Y' class were retrofitted with stronger automatic couplers, which had by then become standard equipment. Some also received air-brakes, but those which retained their vacuum brakes were decommissioned in the late 1980s, coinciding with the eradication of their older 'X' class cousins. Some of these engines made their way into preservation societies.