- Due to the high stretch of synthetic ropes, large amounts of energy can be stored in a line
under load. Sudden failure of the rope can then resuh in a potentially dangerous snapping
back of the line. - Mooring ropes should never be knotted. KnOls weaken a rope considerably, even after they
are removed. - A left-hand rope should Dot be coupled to a right-hand rope.
C.2 INSPECTION OF FIBRE ROPES
Fibre ropes lose strength and deteriorate through normal use and must eventually be replaced. Weak
points aDd potential areas of failure can be detected and the line rcpaired or retired before it pans
in service.
For i nspection, the rope should be laid out and the inspector should rurt the rope between his hands,
examining about a fOOl length at a lime. As he proceeds, he sbould rOlate tbe rope and open the
strands or spread the yams to expose the strand interior surfaces and fibres.
C.3 REPLACEMENT OF FIBRE ROPES
The following guidelines will aid io determining when a fibre rope should be replaced:
- Fibre deterioration. The rope should be retired if the fibre is breaking up or if powdered fibre
is present. - Damage due /0 external wear. For this purpose, an unused rope sample may be helpful for
comparison. If strand crowns are worn down considerably, tbe rope should be retired. lf a
significant number of outer yarns are also severed, the rope should no longer be used as a
mooring Line.- /"ocal abrlllion. Heavy chafing or fusion of surface fibres are indications of severe abrasion. If
these seciions a re localised, they can be removed and tbe rope spliced ill accordance \Iith the
manufacturer's recommendations. - Hockles. Hockling of fibre rope indicates a severe reduction in rope breaking slrengtb. The
hackle should be cut out, if pos5ible, or the rope removed from mooring service. - Chemical attack. Tbis may be indicated by staining, or by the ease with which filamenlS or
fibres from the yarns can be plucked or rubbed off. If the rope has been chemically damaged,
it should be removed from service. - A Ilack by heat. TIlis may be manifested by glazing of the rope surface. In extreme cases,
local fused sections on synthetic rope indicatcs heat tbrough friction and considerable loss of
strength can be expected.
When inspecting mooring lines it is best to be conservative. CuI Oul damaged places if warranted
and .splice following manufacturer's recommendations. If damage is not localised, retjre the rope.