FIGURE 3.14(a): TURNING UP ON SHIP OF SYNTHETIC ROPE TAIL3.10.3 Advantage oj Pulley System
The principal advantage of this equipment: is ihat all moorings can be properly teLlsioned by the
vessel's mooring winches in the nonnal way and manual handling of heavy wires on board is
reduced. Also the problem arising from divided control which can occur with the use of shore wires
en winches is avoided.
While the use of such a system will reduce the load i.D a vessel's moorings in proportion to lhe
number of pulleys provided, its complete effectiveness depends on a vessel's mooring equipment being
in good conditjon initialiy, as with all mooring systems. The tcrmi.naI should evaluate the effect that
ship's tails would have on the loads induced in the mooring lines. Since now there is only one lail
for two lines, the elasticity of each is decreased.
3.10.4 Disadwlnluge of Pulley System
The principal disadvantage of this system i the difficulty of handling the length of wire involved
by using the bight particularly at marginal jelties where moorings may have long drifts. [n addition
care must be exercised to prevent abrasion of the tails when they come back aboard hip. Since the
1ail will usually be in the fairlead, rhe tail can abrade, especiaJly if the fairlead is not smooth or
free of burrs.
To avoid abra ions, some lenninaJs ta.ke th' tail end to a more distant hip's bilt and other.. shonen
the tail by be.laying around the bill (as in Figure 3.1 4 (a».
Both of these affect the elastic ity of the system and mus! be considered when calculating restraint
capacity.
Larger mooring boats may also be necessary to adequately handle heavy bights associated wir.h rhis
system.
3.11 Fire Wires
Terminals require the provl.lon of so-caJled 'fire·wires' or 'towing·off wires'. These are mooring
wires hung OVer the off-be rth side of the ship. They enable tugs 10 pull the. hip away from the pier