M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
• Windlass
• Mooring winches
• Hatch cover openers (pull wire or hydraulic type)
• Winches and derricks or cranes
• Gangways and motors
• Cargo pumps for LPG/LNG or chemical carriers
• Whistle/Horn
• Life boat winch and safety equip. drives…
865
Deck Machinery

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
1. Mooring windlass. Normally either an electric or Hydraulic motor drives 2 cable lifter and 2
warp ends. There are many designs but due to slow speed of cable lifter(3-5rpm) a slow
speed worm gear and a single step spur gear between cable lifter and warp end is used
2. Anchor Capstans. Vertical capstans use a vertical shaft, with the motor and gearbox
situated below the winch unit (usually below decks. With larger cables the capstan barrels is
mounted separately on another shaft
3. Winch windlasses. This arrangement uses a mooring winch to drive the windlass. Both port
and starboard units are interconnected to facilitate standby and additional power should
the situation arise
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Conventional equipment

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
1. Storage part of the mooring drum
2. Pulling section of the drum (working part)
3. Brake band
4. Gear box
5. Electro-hydraulic motor
6. Warping head
7. Chain in the gypsy wheel
8. Dog clutch
9. Anchor
10. Hawse pipe
11. Spurling pipe
12. Chain locker
13. Chain stopper with security device
14. Guide roller
15. Bollard
16. Guide roller
17. Deck
18. Hatch to chain locker
867
Mooring equipment

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
Anchor Drop !
868

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
Basically they require that
 Cable lifter brake shall be capable of controlling
the cable and anchor when disconnected from the
gearing at letting go. The Av. Speed of cable shall be
5-7 m/s.
 The heaving capacity shall be 4-6 times the weight
of one anchor at speeds between 9 and 15
m/minute. The lifting wt shall be between 20-70
tonnes.
 The braking effort obtained at the lifter shall at
least 40% of the breaking strength of the cable.
Anchor Handling
Efficient working of the anchor windlass is essential to the safety of the ship. It’s design and
performance is subjected to strict classification society rules.
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M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
 The windlass must be capable of
pulling the anchor from a depth of
25% of the total cable carried, i.e.
50% of the length of chain on one
side.
 It should be capable of lifting the
anchor from 82.5m to 27.5m at
9m/min.
 Normal anchor handling equipment
incorporates warp ends for mooring
purposes with light line speed of up
to 1m/sec.
Anchor Handling
870

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
• The anchoring equipment fitted to the
majority of vessels consists of two matched
units, offering a degree of redundancy.
• These units consists of an anchor, chain (or
for smaller vessels wire), a gypsum or chain
lifter wheel, brake, lift motor and various
chain stopper arrangements.
• When not in he use the chain is stowed in a
chain locker.
• Systems fitted with wire are stowed on a
drum in the same way as winches.
1. The windlass must be capable of pulling the anchor
from a depth of 25% of the total cable carried, i.e.
50% of the length of chain on one side
2. It should be capable of lifting the anchor from 82.5m
to 27.5m at 9m/min.
871
Anchoring equipment

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
Electric drives
 Should be totally enclosed
 DC drives are still used because they got good
torque range over the full speed though they
need regular attention.
 Control of contactor operated armature
resistance is fully replaced with Ward Leonard
system for good regulation ; especially at
lowering loads ( The present day Ward
Leonard generator is driven by an AC motor)
 DC motors may also be controlled by
thyristors which converts AC to variable DC
voltage.
 AC Induction motors can be wound rotor or
cage type. Speed control being pole changing
or rotor resistance change type. Another form
of AC motor control being VFD drives which
controls the applied frequency and voltage.
Saturday, January 2, 2021 872
Drives

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021 873
Drives
Hydraulic Systems
 provide a good means of distribution of
power obtained from pump driven by a
constant direction/speed AC motor. This
oil can be made to drive thro’ hydraulic
motors to power the actuating devices.
Both constant delivery and variable
delivery type pumps and motors are
commonly use
 The fixed output pumps can be of the
Woodward hydraulic engine governor type
which maintain reserve oil at pressure to
cater to demand

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021 874
Drives
Hydraulic Systems
 Variable displacement pumps can be of
axial or radial piston types where
operational valves can be avoided.
 It is very essential for all hydraulic systems
be provided with interlocking
arrangements for pump and motors so that
control levers remain automatically in
neutral to avoid inadvertent start ups.

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021 875
Drives
Hydraulic Systems
 Overload protection thro’ relief valves to
safeguard system at 30-40% over pressure
Atmospheric contamination isolation, oil
compatibility, system cleanliness, regular
routine maintenance etc. can see thro’ long
periods of trouble free operation

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
• Cargo winch numbers and capacity are decided in
advance keeping in mind the no of hatches and the
size to work.
• The speed varies from 0.45 m/s at full load to
1.75m/s at light load with 40 kw at full load of 7 T
and 20 kw for 3 T
• Advantage of the derrick system is that only 2
winches are reqd. and has a faster cycle time. But
safe working load is less and takes quite some time to
rig up the system prior to cargo work.
• Slewing derrick system was an exception to the above
and which could be rigged up and change in set up
was faster.
876
Deck Cranes

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
Single-opening & Multi-opening. Can be operated by
the ship’s crane or external help. Sealing between
hatch covers and coaming is generally achieved by
sliding rubber packing
877
Lift-away hatch covers

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
The folding pair is operated by hydraulic cylinders acting directly on the end hinge arms which are connected at
stools on the deck. When the cylinders push the end panel up from the closed position, the cover is folded and
the second panel, fitted with wheels, rolls on the rails to the stowage position
878
Hydraulic Folding Types

M a r i n e E n g i n e e r i n g K n o w l e d g e U E 2 3 1 | Y A S S E R B . A . F A R A G2 January 2021
• Side-rolling hatch covers stow in a transverse
direction while end-rolling types stow
longitudinally. The traditional side-rolling cover
consists of two panels per hatch, each panel
rolling sideways on a pair of transverse ramps,
thus presenting a minimum obstacle when
loading. In some cases both panels can be stowed
together on one side to further enhance access
when loading and unloading. This alternative
reduces daylight opening by approximately 50%.
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Rolling types for combination/dry bulk carriers