TM5-3810-305-10
Table 8. Diagnostic Guide to Common Wire Rope Abuses
Abuse
Symptoms
Possible Causes
Fatigue
Wire break is transverse - either straight across
Check for rope bent around too small a radius;
or Z-shaped. Broken ends will appear grainy,
vibration or whipping; wobbly sheaves; rollers too
small; reverse bends; bent shafts; incorrect rope
construction; improper installation; poor end
attachments. All running rope if left in service long
enough will fail by fatigue.
Tension
Wire break reveals predominantly cup and cone
Check for overloads; sticky, grabby clutches;
fracture with some 45-degree shear breaks.
jerky conditions; loose bearing on drum; fast
starts, fast stops; broken sheave flange; wrong
rope size and grade; poor end attachments.
Check for too great a strain on rope after factors
of deterioration have weakened it.
Abrasion
Wire break mainly displays outer wires worn
Check for change in rope or sheave size; change
smooth to knife-edge thinness. Wire broken
in load; overburden change; frozen or stuck
by abrasion in combination with another factor
sheaves; soft rollers, sheaves, or drums;
will show a combination break.
excessive fleet angle; misalignment of sheaves;
kinks; improperly attached fittings; grit and sand;
objects imbedded in rope; improper grooving.
Cut or Gouged Wire ends are pinched down, mashed and/or
Check on all the above conditions for mechanical
or Rough Wire
cut in a rough diagonal shear-like manner.
abuse, or either abnormal or accidental forces
during installation.
Torsion or
Wire ends show evidence of twist and/or cork-
Check on all the above conditions for mechanical
Twisting
screw effect.
abuse, or either abnormal or accidental forces
during installation.
Mashing
Wires are flattened and spread at broken ends.
Check on all the above conditions for mechanical
abuse, or either abnormal or accidental forces
during installation.
Corrosion
Wire surfaces are pitted with break showing
Indicates improper lubrication or storage.
evidence either of fatigue tension or abrasion.
Abrasion plus
Reduced cross-section is broken off square
A long-term condition normal to the operating
Fatigue
thereby producing a chisel shape.
process.
Abrasion plus
Reduced cross-section is necked down as
A long-term condition normal to the operating
Tension
in a cup and cone configuration. Tensile break
process.
produces a chisel shape.
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