Elliott E190, Operation And Maintenance Manual

Page: 126 / 358

Synthetic Rope Usage EEC-0060 V1.2
Synthetic Rope Usage,
Inspection, and Retirement
inspecting for abrasion, glossy or glazed areas, inconsistent diameter, discoloration,
and inconsistencies in texture and stiffness.
Visual Inspection
The load-bearing capacity of double braid ropes is divided equally between the
inner core and the outer cover. If upon inspection, there are cut strands or significant
abrasion damage, the rope must be retired because the strength of the entire rope is
decreased and, as such, is compromised.
Core-dependent double braids have 100 percent of their load-bearing capacity
handled by the core alone. For these ropes, the jacket can sustain damage without
compromising the strength of the load-bearing core. Inspection of the core-dependent
double braids can be misleading because it is difficult to see the core. In the case of 12-
strand single braids, each of the stands carries approximately 8.33 percent, or one-
twelfth, of the load. Upon inspection, if it is discovered there are cut strands or
significant abrasion damage to the rope, the rope must be retired, or the areas of
damage removed and the rope repaired with the appropriate splice.
Abrasion
When a 12-strand, single-braid rope is first put into service, the outer filaments of
the rope will quickly become frizzy. This is the result of the filaments breaking, which
actually forms a protective cushion to shield the fibers underneath. This condition will
stabilize, and should not progress. If the surface roughness increases, excessive
abrasion is taking place and strength is subsequently being lost. When inspecting the
rope, look closely at both the inner and outer fibers. When either is worn, the rope is
obviously weakened.
Open the strands and look for powdered fiber, which is one sign of internal wear.
Estimate the internal wear to estimate total fiber abrasion. If total fiber loss is 20
percent, then it is safe to assume the rope has lost 20 percent of its strength as a result
of abrasion.