OCIMF_Mooring_Equipment_Guidelines_(Second_Edition)

The following table gives guidance on minimum diameters and lenglhs for various ship sizes, however,
lengths may vary dependent on positioning of mooring bitts and vessel's freeboard.

kDWT DIameter (mm) Length Cm)

20-100 28 45

100-300 38 60

over 300 42 70

3.12 Combination of Various Requirements

The requirement for fittings set forth in Sectjons 3.2 (piers), 3.3 (SPMs), 3.5 (MBMs), 3.6 (tug
handl ing), 3.7 (barge moo ring), 3.8 (canal tran it), and 3.9 (STS transfer) do uot apply ..imnltaneously.
In the interest of reducing cost and complexjty, it is desirable during the ship design stage to adjuSI
the location of shipside fairleads slightly so tbat one fair1cad or boUard can serve several requirements.
At the same. time, all po 'sible line le.ads fo r the various requirements mus t be conside red. For
instance, when a shipside falrlead designed primarily for use at piers and sea islands i.n conjunclion
with mooring winches is utilized for require ments 3.5, 3.6, 3.7 or 3.8 or 3.9 measures may be
necessary at the inboard edge if roller fairleads are used. This is especially acute for universal roller
fairJeads since the inboard fore and aft leads are restricted by the end (rame.

3.13 Safety and Operational Considerations

for safety rea.ons, it is highly des irable to k ad mooring lines from winch drums directly to t.he

shipside fairlead. If the use of pedestal fairleads cannot be avoided, the winch controls should be

located to mi.Jlimise risk la the operator.

In the interest, of manpower s.aving. and speedy mooring and un mooring o perations, all mooring

lines should be stowed on drums and consideration given to the provision o f single drum winches

(individual drive for each drum) for aU mooring lines. T his will eliminate the often di fficult task of

clutching and declutching drums from a cOlllmon drive shaft in combination with swing and releasing

drum brakes.

3.14 EQUIPMENT AND FITTING LINE-UP

Mooring finings require adequate clearance for routine operations, and win ches have to be arranged

to pro vide an adequate fleet angle for the drum. This is the ma.ximum angle the line deviates frolll

a direction perpendicular to the drum a;Qs. The following are some 'rule-of-thumb' guidelines.

The minim um distance between a bo llard and fairlead should be 1,8 melres in order 10 provide

adequate space for the application of rope stoppers (see Figure 8.5 for stopper use).

The minimum distance bet weeD a winch drum and the nearest fairlea d shoul.d be such that the fleet

angle does not exceed 1.5^0 • This means tbat Ihe minimum distance 10 the nearest fairlead should

be approximat.ely 19 times the drum width if the line res ts in one pOsition in the fairlead (such as a

pedeSlal fairlead). If the line position within a fairlead is va.riable, lhe distance must be increased to

mect the 1.5° requirement in any po~ition.

[n the case of split drum Winches, only the tension part of the drum should be considered in establish-

ing ma..ximum fleet angles. Figure 3.16 shows thc recommended Line-up for sp!iI drum winches. I1

must be noted that an unloaded line may be paid out or heaved in directly from any part of either

tension or storage drum during lhe beginning and conclusion of mooring operations. J n consequence,

the shaded area shown in Figure 3. 16 mu.st be kept clear of any obstructions.