This document discusses mooring operations and safety. It addresses hazards like snap back zones, improper work processes, and crew competence. It describes the purpose of mooring lines in controlling forces from wind, current, tides and passing ships. Guidelines are provided for effective use of lines and mooring equipment like bollards, rope stoppers, and winches. The importance of communication, preparation, and following procedures is emphasized to promote safety culture during mooring operations.
9. WHAT DOES MOORING SYSTEM DO?WHAT DOES MOORING SYSTEM DO?
ASSIST IN HEAVING SHIP ALONGSIDE.
PREVENTS DRITING AWAY ALONGSIDE
WORKS AGAINST FORCES –
WIND
CURRENT,
TIDES,
SURGES DUE TO PASSING SHIP
CHANGE OF DRAFT
10. HOW BIG ARE FORCES???HOW BIG ARE FORCES???
FORCES ON SHIP (T) = SQUARE OF WIND
FORCES ON SHIP (T)= SQUARE OF
CURRENT
GREATER FREEBOARD * GREATER FORCE
DUE TO WIND
LESSER UKC GREATER EFFECT OF
CURRENT
11. EFFECT OF CURRENTEFFECT OF CURRENT
BEAM CURRENT FORCE INCREASES
AS THE DEPTH/DRAFT RATIO
REDUCES
EFFECT OF UKC ON CURRENT FORCE
50 T
90 T
150 T 200T
CURRENT IKT
5 Df 2 Df
0.2 Df0.5 Df
12. MOORING LINES- CONTROLS FORCESMOORING LINES- CONTROLS FORCES
1
2
1.HEAD LINE- BACKWARD FORCE (-Y)
2.BREAST LINE-TRANSVERSE FORCE (-X)
3. FWD SPRINGLINE – FWD FORCE (+Y)
4.AFT SPRING LINE – AFT FORCE (-Y)
5. AFT BREAST LINE – TRANSVERSE FORCE(-X)
6.STERN LINE – FWD FORCE (+Y)
3
4
5
6
13. EFFECTIVENESS OF LINESEFFECTIVENESS OF LINES
NO SHORT LINES
DIP TO BE LESS THAN 30 DEGREE
(EFFECTIVENESS COSINE OF ANGLE)
SAME DIRECTION
SAME LENGTH
SAME MATERIAL
CARE AND MAINTENANCE
14. SNAP BACKSNAP BACK
Line handlers must operate clear of the potential
snap – back path
Sudden release of stored static energy in the
stretched synthetic line when it breaks.
General rule,10 deg cone around line from point
of break to beyond point of secure to a distance
almost its own length.
16. Method Of Using - Bollards &Method Of Using - Bollards &
Rope stoppersRope stoppers
Two round turn (but not more) around leading
post of the bitts before figure of eighting -
(Distributes the load on bollard evenly )
Gypsy heads(mooring drums) should not be used
to belay the mooring line.
Rope stopper should be of low stretch material.
Material – Synthetic Fiber Rope
Double Stopper is better than Single Stopper.
17. MOORING WINCHMOORING WINCH
RENDER FORCE-Force required to turn winch in
opposite direction when set to heave with the driving
force applied . (EXTERNAL force causing drum to
turn to slack rope)
HEAVING FORCE < RENDER FORCE
BREAK HOLDING POWER REDUCES WITH NO.
OF LAYERS ON DRUM.
Support at lower part of the brake band to be adjusted.
(5mm – 8mm)
WRONG REELING DIRECTION REDUCES BHC
POWER BY 50%.
OIL, MOISTURE,RUST REDUCES BHC BY 75%
18. SPECIFICATIONSSPECIFICATIONS
BRAKE HOLDING CAPACITY-
1. Hawser Strength > BHC (Brake Slips
Before Hawser Brakes)
2. BHC = 60% MBL(Minimum Breaking
Load ) of hawser.
3. BHC > Heaving Capacity.(When brake
slips it is impossible to heave , till force
causing the slip is reduced)
4. RF>BHC>HC ( FOR SAFETY )
19. BHC & Layers on Winch Drum SpecsBHC & Layers on Winch Drum Specs
1. NO OF LAYERS BHC
1ST
100%
2ND
88%
3RD
80%
4TH
73%
5TH
67%
20. SPLIT DRUM WINCHESSPLIT DRUM WINCHES
SAFETY GUIDELINE:
SHIFTING LINE FROM TENSION DRUM TO
STORAGE DRUM
TO TENSION DRUM REQUIRES CARE AND
SUFFICIENT PERSONNEL
NO MORE THAN ONE TURN TO ME
MAINTAINED ON TENSION DRUM.