Engineering Wonders of the World
Volume III
Forfatter: Archibald Williams
År: 1945
Serie: Engineering Wonders of the World
Forlag: Thomas Nelson and Sons
Sted: London, Edinburgh, Dublin and New York
Sider: 407
UDK: 600 eng- gl
With 424 Illustrations, Maps, and Diagrams
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258 ENGINEERING WONDERS OF THE WORLD.
TWO HULETT AUTOMATIC ORE UNLOADERS AT WORK.
The walking beam of the nearer one has been run back from the ship, and the mast has been raised. The unloader
in the background is seen in the act of clipping its mast into the ship’s hold.
number of voyages while the Lakes are open
to navigation.. A consequence of quick un-
loading is naturally cheaper freight rates,
owing to the great saving of labour as well as
of time effected by the marvellous unloading
and stacking machines employed. One of
the most remarkable devices used for the rapid
disembarkation of iron ore is the Hulett un-
loader. This machine consists primarily of
two parallel girders mounted upon a structure
wide enough to span four lines of railway.
The girders are at right angles to the quay.
The whole structure is supported by wheels,
and can be moved along the quay into the
position required for unloading the boat.
Travelling upon the parallel girders is a
trolley carrying a long rocking beam pivoted
at the centre. From the end of this beam
hangs a two-jawed automatic bucket, which
is arranged to be lowered on to the ore with
its two halves apart or open. As soon as the
closing mechanism is put into operation, the
jaws move together, biting into the pile of
ore. Not a small bite, however, as it is noth-
ing extraordinary for one of these buckets to
bring up ten tons of ore. The action of the
machine when unloading a boat is briefly as
follows : The trolley with the walking-beam
travels forward along the girders out over
the boat, until the mast carrying the bucket
at its lower end is above one of the hatches.
The mast then descends until the bucket
rests upon the iron ore, when the bucket is
closed and the mast raised. The trolley then
moves back ; the bucket comes over a large
bin built into the superstructure, opens its
jaws, and discharges the ore. This cycle of
operations is repeated until the boat has been
emptied.
From the bin the ore is dumped through