THE PROPELLING, REFRIGERATING AND LIGHT MACHINERY.

The West Australian (Perth) Tuesday, 24 November, 1903.

The propelling machinery for the vessel

consists of a set of triple-expansion engines, 

built by the Wallsend Slipway and

Engineering Company. Ltd. the cylinders are 

of 32, 51 1/2 and 84 inch diameter

respectively with a stroke of 54 in. Both

the high and intermediate slide valves are

of the piston type, whilst the low-pressure

engine is fitted with a double ported flat

faced valve. The condenser forms no

part of the framing of the engines, but

is entirely independent, being built in of

steel plates. It is supported on suitable

brackets cast on the back columns and

is placed at such a height above the floor

as to give easy access to all the main 

bearings from either front or back of the engine. 

Most sources suggest that Yongala was fitted with a single triple expansion engine driving a single screw - not two engines, which is confirmed by the three cylinder capacities. The low pressure engine referred to, I assume, was for auxiliary power.

The whole of the shafting throughout has 

been made of a strength considerably above 

Lloyd's requirements, and is of ingot steel 

with the exception of the propellor shaft, 

which is of the best selected scrap iron, 

covered with continuous brass liner. 

The propellor is loose bladed with four 

manganese bronze blades.

The air-pump is of the Edward's type,

while the circulating pump, independent

of the main engines, and of the centrifugal

type. There are five large single-ended 

boilers, built in accordance with Lloyds'

and Board of Trade requirements for a

passenger certificate. which can supply 

steam at a pressure of 180 lb. per square 

inch and have a total heating surface of over 

12,600 square feet. The boilers have been

provided with an exceptionally high chimney, 

which has been made double, with an

air space all round to three inches above

the boat deck. 

Yongala consumed 67 tons of coal per day and even the period press referred to her funnel as exceptionally high. I shall return to this interesting feature.

There is pair of feed pumps of Messrs. Weir's make, 

and also a feed heater of the same make. 

The vessel is very completely equipped with 

auxiliary machinery, which comprises, in

addition to that already mentioned, large

evaporator feed filter, auxiliary condensor, 

auxiliary Weir's pumps, fire engine and 

fresh-water pumps, one ash ejector,

and a Crompton ash hoist.

'A direct acting steam windlass and capstan was fitted on the forecastle head.^[2] Cargo handling was done with two steam cranes, along with seven winches with derricks and derrick-posts.' (wikipedia)

'A specially, arranged steam and hand steering 

gear, is fitted in a suitable house at the after end 

of the poop, and controlled from the bridge in the usual

way.'

The refrigerating machinery is by the

Haslam Foundry and Engineering 

Company of Derby, and is on their carbonic

anhydride system, with brine pipes capable 

of dealing with 10,000 cubic foot,

3,000 of which consist of vegetable and

provision rooms, and 7,000 are available

for storage of frozen meat should this be

required at a future time. The vegetable

room is maintained at a temperature of

35 to 40 degrees Fah., and the provision

room at a temperature of 23 degrees Fah.

There is also an ice tank capable of producing 

6cwt. of ice in 12 hours. The vegetable room, 

provision room, and ice tank are for the use 

of the passengers.

courtesy Grace's Guide.

The electric light machinery is comprised of 

two sets of compound engines, driving direct 

separate dynamos at a speed of 240 revolutions 

per minute. As each set is capable of driving 

the whole of the permanent installations on 

board the ship, the chances of a breakdown 

are very remote. The engine and dynamos have been

supplied and fitted by W. H. Allan, of Bedford.

So far I have an impression of a sophisticated steamer built to a high standard for 102 000 pounds. Theoretically she could load between 2000 and 3 000 tons of cargo and provided an exceptional level of comfort for passengers, 5 years before Koombana and Waratah entered the trade. 

SS Yongala (Wreck Site)