Mooring of ships - forces
Kapt. K. De Baere
Mooring of ship TVS 1ste kan
1
Purpose of mooring
configuration
To bring the ship alongside
 To keep the ship alongside
 To assist the ship when un-mooring

Mooring of ship TVS 1ste kan
2
Design criteria of mooring
configurations

Based on the forces acting upon the ship







Wind
Current
Waves
Swell
Other ships passing by (suction effect)
Location of the berth – Protected or sea berth
Types of ship – size, displacement, draught
etc.
Mooring of ship TVS 1ste kan
3
Protected berths


Design criteria – limiting values
 Cross wind up till 15m/sec (6-7
Beaufort)
 Tidal current of 3 knots in longitudinal
direction
 Cross current of 1 knot
Cargo- and container ship are normally
moored along well protected berths =>
Mooring winches are designed to pull the
ship alongside with 1 headline and 1 stern
line against a cross wind of 5 Beaufort
Mooring of ship TVS 1ste kan
4
Sea berths – designed for >wind


Design criteria – limiting values
 Cross winds up till 20m/sec or 8
Beaufort and gust of winds up till
10 Beaufort
 Tidal current of 3 knots in
longitudinal direction
 Cross current of 1 knot
 Waves and swell
Waves and swell with a short period
have a limited influence
Mooring of ship TVS 1ste kan
5
Fetch


The size of a wave depends on its
fetch. The fetch is the distance a
wave travels (see next slide). The
greater the fetch, the larger the
wave.
If the wind is blowing for a longer
period of time in the same direction
=> long fetch with a high wave
height and a longer period =>
important dynamic effect on the ship
Mooring of ship TVS 1ste kan
6
Fetch – Definition
Growth rate of wind generated waves

The distance that wind and seas
(waves) can travel toward land
without being blocked. In areas
without obstructions the wind
and seas can build to great
strength, but in areas such as
sheltered coves and harbours
the wind and seas will be
calmer.
Mooring of ship TVS 1ste kan
7
Mooring of VLCC’s





Often moored outside the harbours along
sea berths
Forces are so great that no winch is
capable of bringing the ship alongside
Tugs are always used when mooring and
leaving berth
The only criteria is the holding force of
the winches
The ship must be maintained in position
related to the shore manifold (chiksans)
Mooring of ship TVS 1ste kan
8
Relation maximum pulling
power – Displacement ()
Figures are used to design shore
facilities (bollards, bits ……….. Etc.)
 25% safety margin to be added

8000 ton – 100 kN
10.000 ton – 300 kN
20.000 ton – 600 kN
50.000 ton – 600 kN
100.000 ton – 1000 kN 200.000 ton – 1500 kN
1 kN = 1 ton pulling power (not scientific)
Mooring of ship TVS 1ste kan
9
Mooring winch with
undivided drum
Mooring of ship TVS 1ste kan
10
Mooring winches – Divided
drum-polyprop octopus
Mooring of ship TVS 1ste kan
11
Chicksan
Mooring of ship TVS 1ste kan
12
Chicksan


Mooring of ship TVS 1ste kan
One of the biggest
problems with the
fixed
loading/discharging
systems is the
restricted liberty of
movement of the
ship
If one of the limits is
breached => ESDsystem activated
13
Assessing the forces
1.
2.
Forces due to wind and current are proportional
to the square of their speeds. f.i. the force caused
by a wind of 40 knots is 4 times the influence of
a wind of 20 knots
The wind speed increases with the height above
the ground. A wind of 10 knots at 2 meters
increases till 60 knots at 40 meters =>
importance of the freeboard (height of the
structure). To obtain comparable figures all
winds are recalculated to a standard height of 10
meters
Mooring of ship TVS 1ste kan
14
Maximum wind limits (400.000 dwt ship)
in function of the breaking power of the
winches
Mooring of ship TVS 1ste kan
15
Wind limits

1.
2.
The previous pictures learns us
that;
The wind limit is determined by the
holding power (breaking power) of
the winches
The wind limit is determined by the
material of the mooring lines
Mooring of ship TVS 1ste kan
16
Assessing the forces
3.
Influence of a cross current is inverse
proportional with the keel clearance. In case of
a small keel clearance the current is obstructed
by the ships hull and searches way out via the
stem and the stern. A Suction effect is created
trying the move the ship away from the berth.
Mooring of ship TVS 1ste kan
17
Theoretical example of the influence
of the keel clearance



A ULCC with a draft of 15 meters is
moored alongside a berth with 16.5
meters of water => relation water
depth/draft = 1.1
Relative resistance factor in case of cross
current = 5.6
In case of unlimited water depth a cross
current of 1 knot produces a force of 60
tons
Mooring of ship TVS 1ste kan
18
Theoretical example of the influence
of the keel clearance


Mooring of ship TVS 1ste kan
In case of a limited
water depth
(example) this
force is increased
till 5.6 x 60 ton =
336 ton
This equals 9 steel
mooring ropes of
40mm diameter
19
Theoretical example of the influence
of the keel clearance
The relative proportion of the
different elements has to be
considered
 Ballasting decreases the keel
clearance but also reduces the
lateral wind surface. The wind effect
is of greater importance than the
the clearance effect (see next slide).

Mooring of ship TVS 1ste kan
20
Example of cross and
longitudinal forces


18.000 & 70.000 SDWT: Wind 60 knots (30m/s),
current 5 knots longitudinal and 1 knot cross
current
200.000 SDWT: Wind 60 knots, current 3 knots
longitudinal and 1 knot cross current
Mooring of ship TVS 1ste kan
21
Conclusions



In ballast condition the most important
forces are wind generated
In loaded condition the most important
forces are current generated
The total force on the ship (alongships +
athwartships) is greater in ballast
condition than in loaded condition =>
influence of the wind is of greater
importance
Mooring of ship TVS 1ste kan
22
Different materials

3 different configurations
All steel wire ropes (equipped or not
equipped with tails)
 All ropes are synthetic
 Mixed systems (synthetic + steel wire
rope)
 New materials

Mooring of ship TVS 1ste kan
23
Steel wire rope + tail
(ralonge de la touline)





Purpose of the tail is to add elasticity to
account for change in tidal heights
Always use 8 strands nylon with an MBL
25% > steel wire rope
To protect against chafing cover splice of
the tail with leather or plastic
The tail is connected to the steel wire
rope by means of a Tonsberg shackle or a
Mandal shackle
In case of frequent use tails are changed
every 18 months
Mooring of ship TVS 1ste kan
24
Steel wire rope + tail





Steel wire rope have a high MBL and are
not elastic.
Steel wire rope are stored on winch
drums with a manual brake
Steel wire rope are relatively easy to
handle up to 40mm  ????
Steel wire ropes last longer than synthetic
ropes
Price steel wire = synthetic
Mooring of ship TVS 1ste kan
25
Tonsberg shackles
Mooring of ship TVS 1ste kan
26
Mandal Shackle
Mooring of ship TVS 1ste kan
27
Full synthetic mooring
configuration



Biggest problem is elasticity
This elasticity can give an important
« sway » (balancer) to the ship (breaking
out)
3 mooring ropes – different materials –
same length (50 m), MBL and load



Steel wire
Polyprop
Nylon
Mooring of ship TVS 1ste kan
–
–
–
0.3m elongation
5m elongation
8 m elongation
28
Breaking out
Mooring of ship TVS 1ste kan
29
Effect of the hawser elasticity on the
restraint capacity
1.
2.
3.
Mooring of ship TVS 1ste kan
Materials with the
smallest elasticity
take the biggest
load
Short rope = big
load
Relation -  is not
linear
30
Full synthetic mooring
configuration


Mooring of ship TVS 1ste kan
Synthetic fibres loose
tensile strength (force
de traction) if
submitted to cyclic
tensions attaining 30 to
50% of their MBL.
Those cyclic tensions
are not constant, due to
resonance high
tensions occure during
short periods of time
31
Full synthetic mooring
configuration

Because of;





Cyclic tensions
Internal friction
Exposure to the marine environment
Tensile strength
diminish after 1
Tensile strength
diminish after 5
Mooring of ship TVS 1ste kan
of synthetic ropes will
year
of steel wire rope will
years => more durable
32
Full synthetic mooring
configuration


Another side effect
is sagging
(affaissement)
The « sag » is
function of;




Mooring of ship TVS 1ste kan
 m-n
Weight of the
mooring line
Tension in the line
Water depth (suction
effect)
33
Full synthetic mooring
configuration




Consequence of the sagging is that a
synthetic rope can never be pulled as stiff
as a wire rope.
A wire rope will « react » faster on a
breaking out of the ship.
A synthetic rope will compensate the the
sag before reacting
Max. allowed distance between berth and
ship is normally limited to 6% of the
water depth
Mooring of ship TVS 1ste kan
34
Mixed mooring systems
Mix of wire ropes and synthetic
ropes
 Certainly NOT the best configuration
but the most common one.
 If possible use steel wire rope as
springs and breasts and use
synthetic ropes as head- and
stern line

Mooring of ship TVS 1ste kan
35
New materials
Composite materials
 Expensive but excellent mooring
system
 Kevlar –Aramid ropes are very
strong, light and show little sagging.
They react fast in case of breaking
out of the ship.

Mooring of ship TVS 1ste kan
36
Efficient mooring

The efficiency of a mooring rope
depends on the following factors




Material (steel wire or synthetic –
elongation & MBL)
Length
Angles with longitudinal and transversal
axis in the horizontal plane
Angles with the horizontal in the vertical
plane
Mooring of ship TVS 1ste kan
37
Function of the different
ropes




Head- and stern lines & the springs are
stabilising the ship alongside
Breast line will prevent the ship to break
free from the berth
Breast lines must be as perpendicular as
possible to the ships longitudinal axis
Springs must be as parallel as possible to
the berth
Mooring of ship TVS 1ste kan
38
Recommendations


The function of springs and breast lines is
clear. Springs are preventing longitudinal
movement while breast are opposing
transversal movements.
The function of head and the stern lines
depends on their angle with the
longitudinal axis. Great angle => they
serve mainly as breast line while small
angle => stopping longitudinal movement
Mooring of ship TVS 1ste kan
39
Recommendations



The ideal configuration will rarely be
achieved.
To obtain a perfect mooring configuration
their must be a perfect harmony between
the ships equipment and disposition on
board and the configuration ashore
Berthing ships is always a matter of
compromises
Mooring of ship TVS 1ste kan
40
Recommendations
Following recommendations have
been published by the OCIMF = Oil
Company International Maritime
Forum
 The recommendations are valid for a
tanker moored alongside a T-berth

Mooring of ship TVS 1ste kan
41
Recommendations based on
OCIMF – Effective mooring
1.
The horizontal angles of head-,
stern- and breast lines < 15°
Mooring of ship TVS 1ste kan
42
Recommendations based on
OCIMF – Effective mooring
2.
The vertical angle with the horizontal
plane must be < 25°




The effective force is proportional to the
cosine of the angle
If the angle is 25° the line is effective for
91%
If the angle is 45° the efficiency is reduced
to 71%
=> Springs & breasts must be long
enough and not to steep
Mooring of ship TVS 1ste kan
43
Springs & Breasts
Mooring of ship TVS 1ste kan
44
Recommendations based on
OCIMF – Effective mooring
3.
Breast lines are most effective is 
on the longitudinal axis.
If  is 45° we have to increase the force in the
breast line till 141 ton to obtain an effective
transversal force of 100 ton
Mooring of ship TVS 1ste kan
45
Recommendations based on
OCIMF – Effective mooring
4.
Springs offer the greatest holding
power in the longitudinal direction.
Their length is  60 meters
Mooring of ship TVS 1ste kan
46
Recommendations based on
OCIMF – Effective mooring
5.


The impact of the head and the stern
lines on the total holding power of the
mooring configuration is less important
than the influence of springs and
breasts. This mainly because these lines
are too long.
Never the less they are important to
compensate the dynamical forces.
Length  110m = ½ coil
Mooring of ship TVS 1ste kan
47
Recommendations based on
OCIMF – Effective mooring
6.
Very short lines must be avoided.
They always take the most
important part of the load,
especially when the ship is moving
Short length = important vertical
angle
Mooring of ship TVS 1ste kan
48
Short breast lines


Long breast line: 52ton load is sufficient to
obtain an effective holding power of 50 ton
Short breast line: Load has to be increased till
88 ton to obtain same result
Mooring of ship TVS 1ste kan
49
Recommendations based on
OCIMF – Effective mooring
7.
All the mooring ropes in the same group
(working in the same direction)must
have a same tension. If not, the
weakest line will break first. Total load
will have to be received by the
remaining lines => increased risk of
breaking (chain reaction)

Groups are f.i. aft spring + head lines, Stern
lines + forward spring, breast lines
Mooring of ship TVS 1ste kan
50
Recommendations based on
OCIMF – Effective mooring
8.
Their must be an equilibrium
between the 4 groups (head- and
stern lines, springs and breasts.
Example: Optimal mooring
configuration is determined after
studying the static and dynamical
forces for a specific berth.
Mooring of ship TVS 1ste kan
51
Mooring example






Maximum breaking out from the berth =
1 meter
Direction of the wind: 110° -> 290°
Frequency 58%
25.2% 3 à 4 Beaufort
0.65% > 8 Beaufort
Proposed configuration all nylon  80mm
(MBL 110 ton):


4 breast lines (aft) + 1 stern line
3 headlines + 3 breast lines (fore)
Mooring of ship TVS 1ste kan
52


The fore ship will resist a wind pressure of
32 knots while the stern will resist a wind
pressure of 33 knots => The berth will be
operational till 7 Beaufort => not
operational 5.8% per year
The configuration of the berth is not ideal
since the horizontal angles > 15°
Recommendations based on
OCIMF – Effective mooring
9.
The number of lines is function of
the size of the ship and the
prevailing weather conditions
A – Panamax (75.000 dwt) - 12 lines (2
headlines – 4 breasts – 4 springs – 2
stern lines: 2 –2 – 2 fore and aft)
B – VLCC (150.000 dwt) 16 lines (4
headlines – 4 breasts – 4 springs – 4
stern lines: 4 –2 – 2 fore and aft)
Mooring of ship TVS 1ste kan
54
A – Panamax & B - VLCC
Mooring of ship TVS 1ste kan
55
Mooring configurations bulk
carriers
Cape Size: 4 –2 – 2 (fore and aft)
 Panamamax: 4 –1– 1 (fore and aft)
 Handy Size: 4 –1 (fore and aft)
 Mini Bulker: 3 –1 (fore and aft)
 Mini Bulker – moored so it can shift
forward and backwards during
loading/discharging

Mooring of ship TVS 1ste kan
56
Mooring
configurations
bulk carriers
Mooring of ship TVS 1ste kan
57
Recommendations based on
OCIMF – Effective mooring
10.
Mooring lines must be passed ashore
using the deck fittings (fairleads)
because of friction and the curvature
relation.
Curvature relation =  curvature deck
fitting/  mooring line
In case of a mooring wire relation has to
be > 20 to reduce loss in tensile
strength
Mooring of ship TVS 1ste kan
58
Mooring configuration –
concentrated on the fore ship
Mooring of ship TVS 1ste kan
59
Mooring of ship TVS 1ste kan
60
Deck fittings
(accessoires
de pont)
OCIMF
equipment:
Panama
hawse- hole
Pedestal
Fairleads
(Chaumard)
Info
Suez & Panama Canal
Mooring of ship TVS 1ste kan
63
Suez Canal
Total length is 190.25 km
 Water surface width is 280.345 m
 Width between the buoys is 195.215 m
 Canal depth is 22.5 m
 Maximum ship draught allowed is 62ft
 Speed allowed for loaded carriers is 13
km/h
 Speed allowed for unloaded carriers is 14
km/h.
 Mooring
Average
transit time is 14 hours
of ship 
TVS 1ste kan
64
Suez Canal
Panama Canal



The Panama Canal is approximately 80
kilometers.
The Canal uses a system of locks
The locks function as water lifts: they raise
ships from sea level (the Pacific or the Atlantic)
to the level of Gatun Lake (26 meters above
sea level)
Mooring of ship TVS 1ste kan
66
Panama Canal



Each set of locks bears the name of the
townsite where it was built: Gatun (on the
Atlantic side), and Pedro Miguel and Miraflores
(on the Pacific side).
The maximum dimensions of ships that can
transit the Canal are: 32.3 meters in beam; draft
12 meters in Tropical Fresh Water; and 294.1
meters long
The narrowest portion of the Canal is Culebra
Cut
Mooring of ship TVS 1ste kan
67
Panama Canal
Mooring of ship TVS 1ste kan
68
Gatun Lock
Mooring of ship TVS 1ste kan
69
Gaillard
Cut
Pedro Miguel Locks
Mooring of ship TVS 1ste kan
71
Mira Flores Locks
Mooring of ship TVS 1ste kan
72
4-roller fear
lead Towing
Bracket
Smit Towing Bracket
Mooring of ship TVS 1ste kan
74
Chocks and buttons
Mooring of ship TVS 1ste kan
75
Bits and Bollards
Mooring of ship TVS 1ste kan
76
Panama chocks
Mooring of ship TVS 1ste kan
77
Roller Chocks
Mooring of ship TVS 1ste kan
78
Roller Fairleads
Mooring of ship TVS 1ste kan
79
Towing pads (point d’attache pour le
câble de remorque)
Mooring of ship TVS 1ste kan
80
Emergency Towing Systems



SOLAS Requirement
Regulation Chapter II-1, A-1, 3-4
Since 1996, January 1, all tankers exceeding,
20,000 DWT are to have an emergency towing
arrangement fitted at the aft and forward. This
IMO resolution MSC35(63) which covers the
installation of emergency towing arrangements
on tankers was decreed after the unfortunate
disaster of the MV Braer in 1993.
Mooring of ship TVS 1ste kan
81
Emergency Towing Systems
- Aft beneath deck
Mooring of ship TVS 1ste kan
82
Emergency Towing Systems
Typical Arrangements Fwd
Mooring of ship TVS 1ste kan
83
Demo
Mooring of ship TVS 1ste kan
84
Mooring alongside a classic
berth (quay)
Mooring of ship TVS 1ste kan
85
Mooring alongside a classic
berth (quay)
Different methods – see lab ship’s
technique
 Practical techniques – see lab ship’s
technique

Mooring of ship TVS 1ste kan
86
Mooring
alongside a
classic
berth
(quay)
Mooring of ship TVS 1ste kan
87
Mooring alongside a T-berth
Mooring of ship TVS 1ste kan
88
Mooring with 2 anchors
Mooring of ship TVS 1ste kan
89
Ship to ship
Mooring of ship TVS 1ste kan
90
SPM – Single Point Mooring
Buoy
Mooring of ship TVS 1ste kan
91
SPM - buoy
Mooring of ship TVS 1ste kan
92
SPM - buoy
Mooring of ship TVS 1ste kan
93
FPSO – single point mooring
Mooring of ship TVS 1ste kan
94
FSO - operations
Mooring of ship TVS 1ste kan
95
STL – Submerged Turret
Loading
Mooring of ship TVS 1ste kan
96
STP – Submerged Turret
Production
Mooring of ship TVS 1ste kan
97
STP – Submerged Turret
Production
Mooring of ship TVS 1ste kan
98
Safe fibre ropes
1.
2.
3.
4.
Ropes should be covered when they are
not being handled, and stowed away when
not in use at sea, to prevent
contamination by oils and chemicals, and
degradation by sunlight.
Ropes must be kept away from heat, oil,
paint and chemicals.
Ropes should be stowed on gratings for
ventilation and drainage.
Ropes must be examined regularly for
wear, stranding, melting and powdering,
and replaced if serious defects are found.
Mooring of ship TVS 1ste kan
111
Safe Wire Rope
1.
2.
3.
Wires should be lubricated regularly with
an approved lubricant.
Everyone who handles wires should wear
leather -palmed gloves to protect their
hands from snags.
Wires must be examined regularly for
wear, stranding, dry core, kinks, and
excessively flattened areas. They must be
replaced if the number of broken strands
(snags) exceed 10% of the strands in any
length equal to eight diameters, or if any
other serious defects are found.
Mooring of ship TVS 1ste kan
112
Safe line handling – see lab
1.
2.
Flake out all mooring lines on the deck,
clear, and ready to send. This will ensure
that any fibre lines which have become
buried on reels can be freed in advance,
when there is less likelihood of accidents.
Do not use a wire direct from a reel
designed only for stowing.
Have all necessary heaving lines,
messengers, tails and stoppers available
at the mooring station, and rat guards
ready for use.
Mooring of ship TVS 1ste kan
113
Flaking out mooring lines
Lover les
aussières à la
française
De trossen zijn
klaar gelegd in
franse bochten
To avoid that someone puts his foot/feet in a
loop
Mooring of ship TVS 1ste kan
114
Safe position between
mooring ropes

Mooring of ship TVS 1ste kan
Position yourself
away from the
whip
115
Putting the mooring rope on the
warping head of the winch

Mooring of ship TVS 1ste kan
The anchor winch
has maximum
power when it runs
in the sense of
picking up the
anchor (anti-clock
wise)
116
Safe line handling – see lab
3.
4.
Have sufficient crew available.
All crew should wear safety helmets and
safety shoes, and have no loose clothing
which could become entangled in the
winches or trapped by the lines. Gloves
should be tight fitting, to reduce the risk
of becoming trapped by lines, and should
have a leather palm to protect the hand
against abrasion and prevent wounds
caused by snags of wires; they should
provide adequate insulation in cold
weather.
Mooring of ship TVS 1ste kan
117
Safe line handling – see lab
5.
6.
When one seaman is handling a line on a
drum end, he should not stand too close
to the drum to avoid being drawn in.
There should be an additional seamen
whose duty is to clear the loose line when
heaving, and supply the loose line when
slacking.
The person operating the winch controls
should have a clear view of the entire
area including any seaman handling lines
with that winch.
Mooring of ship TVS 1ste kan
118
Traditional stopper

Mooring of ship TVS 1ste kan
A traditional
stopper using a
single line may be
used only on a
mooring line made
of natural
materials, as shown
below, but such
mooring lines are
no longer common
on board ship
123
Safe line handling – see lab
Stand well clear of all lines under tension.
This means everybody, not just those
handling that line.
16. Synthetic fibre ropes may break without
warning, and the resultant whiplash may
cause severe injuries or even death.
17. Synthetic fibre mooring ropes should be
stoppered using two tails of fibre rope,
halfhitched under the mooring rope, with
the two free ends criss-crossed over and
under, as shown in the diagram below:
(This is sometimes known as a Chinese
stopper.)
Mooring of ship 15.
TVS 1ste kan
124
Safe line handling – see lab
18.
Mooring wires should be stoppered using
a chain stopper with a well-spaced cow
hitch (Lark’s head)(Deux demi clefs
renversées)(it is recommended that the
two hitches are at least 25 cm. apart) and
with the remainder of the chain and its
rope tail turned up several times against
the lay, as shown in the diagram below.
The cow hitch is used because it is easily
pulled loose when no longer required, a
clove hitch (mastworp -Deux demi clefs à
capeler (noeud de cabestan)) is likely to
jam.
Mooring of ship TVS 1ste kan
125
Chain stopper
Mooring of ship TVS 1ste kan
126
Safe mooring
1.
2.
All operations must be carried out ONLY
under the direct orders of the supervising
officer.
The supervising officer must ensure that
communications with the bridge are CONTINUOUSLY maintained. If using radios
all calls should start with the ship’s name
(to avoid confusion), and then the caller
should immediately identify himself and
who he is calling to avoid confusion on
one’s own ship A spare fully-charged
battery should be carried whenever portable
radios are used. A back up system must be
readily available at all times.
Safe mooring
3.
4.
5.
6.
Check with the bridge before sending the
first lines, and before making any lines
fast.
Keep the bridge informed of distances off
the quay, any obstructions and other
moored ships, lighters or other floating
objects.
Advise the bridge if there is any
possibility that a slack line may become
entangled in the propeller - or thrusters.
Warn the bridge if any lines become
excessively taut.
Mooring of ship TVS 1ste kan
133
Safe mooring
7.
8.
9.
Make fast and cast off tugs only on orders
from the bridge.
When heaving lines are being thrown,
ensure that all personnel ashore and on
board are alerted, and stand well clear.
The supervising officer must make sure he
can always see both the winch operators
and the particular line when giving orders
for adjusting the tension in a line.
Mooring of ship TVS 1ste kan
134
Safe mooring
10.
11.
12.
Secure the lines as per the Master’s
orders. i.e. which lines to leave on the
drums, which lines to make fast on bitts,
Which lines to leave in auto/self-tension,
if any, and what level to set the controls.
Ensure rat guards are properly fitted to all
lines.
The supervising officer must remain at the
mooring station, with his full crew, until
he is dismissed by the Master.
Mooring of ship TVS 1ste kan
135
Plague Control ?
Deratisation
 Rat guards

Mooring of ship TVS 1ste kan
136
Mooring of ship TVS 1ste kan
137
Mooring of ship TVS 1ste kan
138
Mooring of ship TVS 1ste kan
139
Self Tensioning Winches

Self tensioning winches can be set to a
certain holding force. If this value is
exceeded, then the winch automatically
adjusts the length of wire to the new force
(too much holding force: slacking; too little
holding force: heaving). This system is
frequently used by ships that load and
discharge quickly (container ships and RoRo-vessels) or if there is a large tidal range
in the port.
Mooring of ship TVS 1ste kan
140
Self Tensioning Winches
1.
2.
3.
Mooring of ship TVS 1ste kan
Control lever for the
winch
Cooling fan
Control for the selftension setting
141
Self Tensioning Winches


The heaving power of a winch is always lower than its
render force. This means that if a winch is left in selftension, and the external forces increase, the line will pay
out, and it may not be possible to heave it in again until
such external forces reduce. Also, the render force of the
winch is much less than the holding power of the brake
Self-tensioning winches at opposite ends of the ship can
work against each other, so that the ship can sometimes
‘walk’ along the berth, when an external force is applied
at one end.
Mooring of ship TVS 1ste kan
142
Self Tensioning Winches


Hence it is recommended that mooring lines are NOT left
in self-tension once the ship is secure alongside. With
short breast lines in fair weather, these controls may be
useful during rapid load/discharge operations. However,
those winches which are directly counteracting any
external forces must be left on the brake.
Self-tensioning winches are useful during berthing
operations with reduced manning, as once the line is
ashore and the controls set, they will reel in any slack,
maintain the tension in the line, and prevent the line being
damaged through excessive strain.
Mooring of ship TVS 1ste kan
143
Keeping moorings taut


The OOW must ensure that the mooring lines are kept
sufficiently taut at all times to keep the ship firmly
alongside. At rapid loading or discharging berths, the
Chief Officer may assign additional crew to assist the
OOW, as the operation of adjusting the lines may have to
be done frequently. The 00W must never attempt to adjust
a mooring line by himself, unless it is permanently wound
on its own drum.
If the lines are not in equal tension, they may part in
succession if the ship is subject to exceptional high forces,
such as very strong winds, large swells or water surges
from other ships passing too close and/or too fast.
Mooring of ship TVS 1ste kan
144
Keeping moorings taut
Brake linings can lose their grip when oil and rust are
present, and are susceptible to loss of holding power
during periods of rain or high humidity.
 The OOW should remember to adjust any fire wires as
the ship’s freeboard changes, to ensure that their ends
remain clear of the water.
 It is essential for the OOW to check the moorings when
other ships are arriving at or leaving from the berth
immediately ahead or astern of their ship.
 It is good practice for the OOW to be in attendance
forward or aft whenever the adjacent ship is arriving or
sailing to watch out for contact damage, or other
incidents,
Mooring
of ship in
- addition to monitoring the moorings.

TVS 1ste kan
145
Fire wire






Strong steel wire
1 end is put on a
bollard
Other end is hanging
overboard +/- 1 meter
above the water
The outer end is held in
position by means of a
weak line.
Middle part is flaked
out on deck
In case of fire a
tugboat can grab the
outer eye and pull the
tanker free of the berth
Excerpt from terminal rules and
regulations - Saoudi Arabia

TOWING-OFF WIRES OF ADEQUATE STRENGTH
AND CONDITION MUST BE MADE FAST TO
BOLLARDS ON THE TANKER. FORWARD AND AFT,
AND THEIR EYES RUN OUT AND MAINTAINED AT
OR ABOUT THE WATERLINE. THE WIRES MUST BE
OVER THE OFFSHORE SIDE.
IN ORDER THAT SUFFICIENT WIRE CAN BE PUT
OUT TO ENABLE THE TUGS TO TOW EFFECTIVELY,
ENOUGH SLACK MUST BE RETAINED BETWEEN
THE BOLLARD AND CHECK AND PREVENTED
FROM RUNNING OUT BY A ROPEYARN OR OTHER
EASILY BROKEN MEANS
Mooring of ship TVS 1ste kan
147
Chafing (Frotter – Raboter)

The OOW must check the moorings at least hourly during
his watch, not only to ensure they remain taut but also to
look out for chafing, where the rope rubs against an
obstruction, and may part. This may occur when the ship
is surging back and forth along the quay due to a large
swell, or when there is excessive movement of a mooring
buoy. Synthetic fibre ropes possess very low resistance to
chafing when under load; the friction generates heat
which causes them to melt and fuse, and the rope is then
permanently weakened, and may part quite quickly.
Mooring of ship TVS 1ste kan
148
Chafing (Frotter – Raboter)

Ropes may chafe by rubbing against each other, or
against the ropes of another ship. The officers on stand-by
fore and aft during mooring operations must be alert for
this when sending ropes to different bollards ashore
through different leads on board. If they notice any
chafing, they should have that line removed and sent from
a different lead. Short leads with substantial dips are
prone to chafing on the ship’s structure.
Mooring of ship TVS 1ste kan
149
Chafing

Sometimes a change in freeboard, or some external
factors such as a change in the sea state, may cause lines
to start chafing. If he notices any chafing, OOW must
clear the obstruction, change the lead of the mooring rope,
or wrap the rope in canvas or some other material to bear
the rubbing and wearing away action. The outside of the
canvas may be greased to reduce the friction, but this
grease must not be allowed to remain in contact with fibre
ropes as it will cause them to deteriorate. The OOW must
always advise the Chief Officer of his observations and
actions.
Mooring of ship TVS 1ste kan
150
Emergencies

Occasionally unexpected changes of load may cause the
brakes of the mooring line drums to slip, and the vessel
is at risk of moving off the berth. DO NOT RELEASE
THE BRAKES AND ATTEMPT TO HEAVE THE SHIP
BACK ALONGSIDE USING ONLY THE POWER OF
THE WINCH.
The recommended action is:
1.
2.
If the winches are in self-tension apply the brakes IN
ADDITION.
If the brakes are in use, tighten them, put the winch in
gear and heave on as many lines as possible.
Mooring of ship TVS 1ste kan
151
Emergencies
3.
4.
5.
6.
Inform the senior officers, and seek extra crew
assistance
Summon tug assistance if necessary.
Consider reducing the freeboard by ballasting.
The OOW should remember that brake holding power
is always greater than winch heaving power, but that
the two together increase the load.
For example:
Winch render force
= 35 tonnes.
Brake holding power
= 65 tonnes.
Total holding power
= 100 tonnes.
Mooring of ship TVS 1ste kan
152
Emergencies
He should be careful this does not exceed the breaking
strain of the rope, or the safe working load of the leads
and rollers. However, in an emergency it will usually be
preferable to endeavour to hold the ship in position and
risk breaking the lines.
Mooring of ship TVS 1ste kan
153
Mooring
equipment
ashore
Mooring of ship TVS 1ste kan
154
Equipment ashore
Bollards and bitts
 Winches - capstans
 Quick release hooks
 Laser docking systems
 Mooring line monitoring systems
 Fenders

Mooring of ship TVS 1ste kan
155
Bitts and bollards
Mooring of ship TVS 1ste kan
156
Capstans
Mooring of ship TVS 1ste kan
157
Quick Release Hooks
The basic starting point to any integrated
mooring system
 Can be released manually or (electric,
hydraulic or telemetry) and can
incorporate load pins for optional
multipoint computer-based remotely
mooring line tension monitoring systems

Mooring of ship TVS 1ste kan
158
Quick Release Hooks
Mooring of ship TVS 1ste kan
159
Quick release hooks
Explosion proof double
hook unit
Quad. hook with load
monitoring and
remoter release
system
Mooring of ship TVS 1ste kan
160
Mooring Line Monitoring
System


Mooring of ship TVS 1ste kan
The vessel Mooring
Line Monitoring system
(MLM), provides real
time monitoring of all
mooring lines and
warns of excessive or
out-of-range loads.
Changing weather
conditions or current
loading can cause
unequal load sharing
within the mooring
system. This can lead
to potential failure of
mooring lines and
damage to jetty
161
Mooring Line Monitoring
System



Mooring of ship TVS 1ste kan
Load on the hooks is
measured by load
pins
Data is transferred to
the jetty control room
Data is completed
with environmental
data and data
concerning the
movement of the ship
alongside
162
Environmental data

Mooring of ship TVS 1ste kan
Data is collected
by a buoy and
presented on
graphic display
163
Laser docking systems


The primary benefit of a Docking Aid System
or DAS is the provision of real time data of the
vessel’s position and progress relative to the
jetty by measuring distance from the jetty and
speed of approach in the critical 0 to 200
meters zone.
With this data the vessel’s master and pilot
can better direct tug and shipboard personnel
in the safe manoeuvring of the vessel towards
the
jetty and minimize any potential for
Mooring of ship TVS 1ste kanto the berth
damage
164
Laser docking systems



Mooring of ship TVS 1ste kan
Typically, two sensors are located
on the jetty measuring distance to
bow and stern sections of the
ship.
This together with average speed
are captured at the jetty control
unit and displayed to the ship and
mooring crew on wireless monitor,
computer screen or jetty mounted
display board, as required.
Earlier systems used radar
sensors, however today laser
sensors are the most reliable
technology employed for vessel165
Laser docking systems
Mooring of ship TVS 1ste kan
166
Docking systems – GPS
based f.i. e-fix system






Mooring of ship TVS 1ste kan
Ship trials (speed and
manoeuvring)
Oil and gas tanker
approaches and docking
operations
SPM/FSO Docking and
Drift Warning
Oil rig positioning
Navigation of ships into
locks & docks
Ferry operations
167
Docking systems – GPS
based f.i. e-fix system
It should be noted that the E-Sea Fix system can be
integrated into existing Laser Docking Systems.
 All data from an existing Laser Docking System
(such as environmental data, load arm monitoring,
mooring load monitoring and drift warning
information) can be relayed and displayed on the
pilot monitor.
 A receiver is capable of receiving signals from both
the US constellation as well as the Soviet based
GLONASS constellation. This dual constellation
ensures that the number of satellites visible to the
receivers
Mooring
of ship - is maximised.

TVS 1ste kan
168
Accuracy
Speed accuracy better than any ship’s
log, ± 1 cm per second i.e. ± 0.02 knots
 Heading accuracy better than any gyro
system, approximately ± 0.01 degree
 Rate of turn better than any rate gyro
system, approximately ± 0.02
degree/second and up
 Position accuracy to a few centimetres

Mooring of ship TVS 1ste kan
169
Docking systems – GPS
based f.i. e-fix system


Mooring of ship TVS 1ste kan
Signal is used as
input for an ECDIS
based on C-map or
S-57 maps.
Portable version
exists
171
Berth management systems

A « Berth Manager» monitors the vessel
approach, mooring load and environmental
situation in a single integrated system, with a
range of optional displays, readouts and
functions, and provides the port operator with
comprehensive reporting on the behaviour of
vessels while in the confines of the port. The
system assists the docking procedure and
monitors mooring performance.
Mooring of ship TVS 1ste kan
172
Berth management systems
Mooring of ship TVS 1ste kan
173
Fenders

Used to:
Divide the load
 Protect the berth
 Protect the ship


Fenders can be fixed or mobile
Mooring of ship TVS 1ste kan
174
Yokohama Fenders
Mooring of ship TVS 1ste kan
175
Yokohama Fenders
Mooring of ship TVS 1ste kan
176
Fixed fenders
Mooring of ship TVS 1ste kan
177
Mooring equipment on
board
Mooring of ship TVS 1ste kan
178
Mooring equipment on
board
Heaving line (ligne d’attrape)
 Messenger (grelin)
 Tails

Mooring of ship TVS 1ste kan
179
Heaving line (ligne
d’attrape)
Mooring of ship TVS 1ste kan
180
heaving line (Ligne
d’attrape)
Mooring of ship TVS 1ste kan
181
Messenger - grelin
Mooring of ship TVS 1ste kan
182
Tail (allongement de la
touline)
Mooring of ship TVS 1ste kan
183
Passing ropes ashore




Before arriving at the dock all crewmembers should
put on their Personal Protective Equipment and
move out onto the deck. All lines should be
prepared for docking making sure that they will feed
out freely.
There should always be someone on the dock to
receive the line.
Do not attempt to throw the line to the bitt.
If the boat is to be moored some distance from the
dock a messenger line (grelin) with a monkey’s fist
can be thrown and then hauled in to transfer the
mooring line safely to the dock.
Mooring of ship TVS 1ste kan
184
Passing ropes ashore


If you are sharing the bitt or bollard with another
vessel feed the eye of the mooring line through the
eye of the line already on the bitt and then place the
eye over the bitt.
This will allow you or the other vessel to quickly
remove a line without disturbing the remaining line.
Mooring of ship TVS 1ste kan
185
Passing ropes ashore
Mooring of ship TVS 1ste kan
186
Putting 2 ropes on the
same bitt
1.Wrong
2.Correct
The « other » ship
can leave without
disturbing our
mooring
configuration
Mooring of ship TVS 1ste kan
187
Passing ropes ashore

While handling lines you must be very conscious of
the placement of your hands and feet in proximity to
the line. Never put your hand in the bight of the line
at the bitt, and watch that you do not step into the
bight of the line on the deck with your foot. If the
boat surges you can be caught in an instant,
resulting in serious injury or death.
Mooring of ship TVS 1ste kan
188
Passing ropes ashore

Mooring of ship TVS 1ste kan
Never place yourself in
a position where the
line can pinch you up
against the bulwarks or
equipment on deck.
You will never be able
to move quick enough
to get out of the way or
have the strength to
keep the line off you!
189