Whilst you wait for the Scenic Railway ride to download,
you may be
wondering how safe it is...
By the time you read this, the ride will
probably have finished downloading.
The Scenic Railway's winch or winder has four main parts:
- The main drum on winch are wound the twin ropes that are
attached to the Scenic Railway train.
- The counterweight drum which winds the rope that is attached to
the six-tonne aerial counterweight.
- The David Brown gearbox.
- Reliance Electric DC 15Okw motor.
There is also a 150 kw standby slip ring electric motor connected
to a common input shaft on the gearbox.
Drums
The main drum is 2.5m in diameter and is grooved to guide the rope
to wind on to the drum perfectly. The ropes are 28mm in diameter and
when tested broke at 57 tonnes. The ropes are 480m long. One rope is
right hand lay and the other left hand lay. This means that the strands
of the rope are laid in a clockwise direction for the other. This
system is used because the ropes are wound on to the drum from the
outside into the centre in order to keep the stresses on the shaft
symmetrical, and the natural twist of the ropes helps the ropes to
wrap on to the drum correctly.
The counterweight drum is 2.4m in diameter and also is grooved. Its
rope is 24mm in diameter and when tested broke at 43.6 tonnes. This
rope is 597m long.
Brakes
Both drums are equipped with 3m diameter discs which are braked by
Hagglund disc callipers. Each of these callipers is capable of
stopping the winch fully loaded on the steepest grade all by itself,
and there are four of them on two different brake circuits.
The brakes are controlled by a separate Toshiba computerised
processor. This unit is battery powered so that in the event of a
power failure it can still control the emergency stopping of the winch
by providing different rates of deceleration depending on whether the
train is going up or down, and where it is on the incline.
This system is again backed up by a mechanically tripped braking
circuit controlled by the Logan Lily controller which will trip under
certain conditions of overspeed or overwind. If the winder approaches
or leaves either end too quickly, overspeeds anywhere in between, or
travels too far at either end, the first circuit of brakes are
applied. If these brakes don't work then the second "back
up" braking circuit is used. These may be a bit more savage in
their application but it will absolutely stop the winder.
The drums, shafts and brake discs were made in Sydney by Australian
Winch and Haulage P/L and the assembly, which weighs 19 tonnes, was
lowered into place on the foundations by a 90 tonne capacity crane.
The foundations contain 50 cubic metres of concrete.
Controls
The DC drive motor is driven from a motor generator set via an
"Automax" computerised processor. The winder is fully
automatic and is controlled from the train by radio codes.
The winder can also be controlled from the control desk behind the
winder. From here the three TV cameras that monitor the platforms and
the incline can be operated.
The auxiliary emergency drive equipment is also controlled from
this desk. It can recover the train from anywhere on the incline in
the event of a failure in the main drive.
The winch was commissioned on Saturday, 24th July, 1993, at a final
cost of $2,000,000.
The winder operates the train at a speed of 4 metres per second
which is slightly faster than the winch it replaced at 3.8 metres per
second. However, because of the longer loading times involved with the
three carriages, the return trip time has actually become longer, from
six minutes to seven minutes. The Scenic Railway's theoretical
passenger capacity is now 720 per hour.
Ropes
The ropes are expected to have a working life of 50,000 trips which
should take approximately three years. They are tested every year with
a special non-destructive magnetic testing machine which can detect
any broken or corroded wires. The entire drive system for the Scenic
Railway can he driven by our 500KVA Caterpillar 3412 diesel generating
plant.
Source: Blue Mountains Tourist Newspaper |
