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The following photos are of dredgers used at Swansea & Port Talbot.
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Bucket dredger ‘Abertawe’
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One of the ‘Foremost’ hoppers
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Grab dredger ‘Kenfig’
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Grab dredger ‘Ogmore’
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Grab dredger ‘Rhymney’ on C Shed Wharf
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Grab dredger ‘Rhymney’ beached for inspection
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Bed-leveller tug ‘Flatholm’
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Suction dredger ‘Afan’ (see article from ‘Eagle’ comic below)
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John Allnutt standing alongside the former ABP dredger ‘Aberavon’
in Madeira
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Grab dredger ‘Aberavon’ in Port Talbot Tidal Harbour
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The following article is an extract from The Eagle comic dated
17th of November 1962
There is always work for dredgers. Shifting sands and mudbanks can
threaten the safe navigation of ships in river estuaries and in the
approaches to many ports and harbours. Channels have to be cleared at
regular intervals and the spoil – mud or sand – dumped out at sea where it
is out of harm’s way.
One of the latest suction dredgers is the twin–screw diesel electric
Afan, built in the early 60’s by Richard Dunston Ltd. She works out of
Cardiff, and her duties are to keep clear the approaches to the ports of
Swansea and Port Talbot.
She has two large electrically driven pumps, each of which sucks up
the spoil from the sea bed through two trailer suction pipes that are
lowered either side of the vessel. Most of the water brought up with the
spoil is then separated in a distribution box and returned overboard,
leaving the solid matter to be fed into the ship’s two large hoppers. This
is later dumped at sea through the doors at the bottom of the hoppers.
Two 920 h.p. diesel engines drive the generators which supply power
to the propulsion motors and the suction pump motors. All the generators and
the motors were built in the UK by Brush Electrical Engineering.
This drawing was produced by L. Ashwell
Wood. Several attempts have been made by ourselves and others to establish
copyright ownership, but without success. We therefore trust that the
copyright owner, should any exist, will not object to us showing the drawing
on our site.
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Key to Numbered Parts
(
1 ) Suction nozzle on sea bed. (2) Starboard trailer suction pipe;
another is on the port side (not shown). (3) Flexible joints. (4)
Pipe joint which is lowered over the ship's side to connect with
the suction valve and pump. (5) Stone separating box (6) and (7)
Centrifugal suction pumps. (8) 250 h.p. pump motors. (9) Davit for
lowering and raising the trailer suction pipe. These pipes are
stowed on deck when not in use. (10) Discharge pipes to
distribution box. (11) Forward hydraulic ram for operating hopper
door. (12) Port trailer suction pipe davit. (13) Sluice valves,
one either side, discharge spoil into forward hopper. (14) Forward
hopper being filled. (15) Separated water being discharged
overboard. (16) Davit for stowing trailer pipes on deck. (17) Port
sluice valves. (18) Spoil distribution box to all six valves. (19)
Starboard sluice valve to rear hopper (closed). (20) Trays for
distributing spoil into hopper. (21) Chain pulleys for hopper
doors. (22) Rear hopper; each hopper has a 500 cubic yard
capacity. (23) Side buoyancy space. (24) Hopper discharge doors —
six to each hopper. (25) Hydraulic ram for operating hopper doors.
(26) and (27) Pumps, sluice valves, hopper door controls. All
dredging operations are remote-controlled from the bridge, as is
the propulsion machinery. (28) Streamlined funnel, with exhausts
from engine-room. (29) Engine-room hatch and ventilator. (30)
16-ft. aluminium lifeboat. (31) Crew's accommodation. (32) Oil
fuel bunker. (33) 920 h.p. Ruston Hornsby Diesel engines (port and
starboard). (34) Propulsion generator. (35) Auxiliary lighting
Generator. (36) Suction pump generator. (37) Circulation pumps.
(38) Auxiliary Diesel generator. (39) and (40) 610 h.p. propulsion
motors, driving the twin propellers. (41) Reduction gearbox. (42)
starboard propeller. (43) Balanced rudder. (44) Stern anchor. (45)
Anchor winch. (46) 12-ft. work boat.
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Illustration showing the hopper’s bottom discharge doors
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Suction dredger ‘Swansea Bay’
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Suction dredger ‘Welsh Bay’ alongside Port Talbot Harbour Jetty
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Suction dredger ‘Bluefin’ in the River Afan
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Suction dredger ‘Baglan’ berthed at G Shed, Prince of Wales Dock |
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