STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

Hoisting System 615
Wire-Rope Trouble
Damage by hooking back slack too
tightly to girt.
Damage or failure on a fishing job.
Lengthening of lay and reduction
of diameter.
Premature breakage of wires.
Excessive wear in spots.
Spliced rope.
Abrasion and broken wires in a
straight line. Drawn or loosened
strands. Rapid fatigue breaks.
Reduction in tensile strength or
damage to rope.
Distortion of wire rope.
High strands.
Wear by abrasion.
Fatigue breaks in wires.
Possible Cause
Operation of walking beam causing a bending
action on wires at clamp and resulting in
fatigue and cracking of wires, frequently
before rope goes down into hole.
Rope improperly used on a fishing job,
resulting in damage or failure as a result of
the nature of the work.
Frequently produced by some type of overloading,
such as an overload resulting in a
collapse of the fiber core in swabbing lines.
This may also occur in cable-tool lines as a
result of concentrated pulsating or surging
forces that may contribute to fiber-core collapse.
Caused by frictional heat developed by pressure
and slippage, regardless of drilling depth.
Kinks or bends in rope due to improper
handling during installation or service. Divider
interference; also, wear against casing or hard
shells or abrasive formations in a crooked
hole. Too infrequent cutoffs on working end.
A splice is never as good as a continuous
piece of rope, and slack is liable to work back
and cause irregular wear.
Injury due to slipping rope through clamps.
Excessive heat due to careless exposure to
fire or torch.
Damage due to improperly attached clamps or
wire-rope clips.
Slipping through clamps, improper seizing,
improper socketing or splicing, kinks, dog
legs, and core popping.
Lack of lubrication. Slipping clamp unduly.
Sandy or gritty working conditions. Rubbing
against stationary object or abrasive surface.
Faulty alignment. Undersized grooves and
sheaves.
Excessive vibration due to poor drilling conditions,
i.e., high speed, rope, slipping, concentration
of vibration at dead sheave or dead-end
anchor, undersized grooves and sheaves,
and improper selection of rope construction.
Prolonged bending action over spudder
sheaves, such as that due to hard drilling.