8. Broken Wires
Some sections of rope can break up without any prior warning. Already discussed in some
detail as to cause and effect, sections where this occurs are ordinarily found at the end
fittings, and at the point where the rope enters or leaves the sheave groove of boom hoist,
suspension systems, or other semi-operational systems. Because of the “working” that
takes place at these sections, no appreciable wear or crown breaks will appear. Under
such an operation, the core fails thereby allowing the strands to notch adjacent strands.
However, when this happens, valley breaks will appear. As soon as the first valley break is
detected, the rope should be removed immediately.
If preventative maintenance, previously described, is diligently performed, the rope life will
be prolonged and the operation will be safer. Cutting off a given length of rope at the end
attachment before the core deteriorates and valley breaks appear, effectively eliminates
these sections as a source of danger.
EQUIPMENT INSPECTION
Any undetected fault on a sheave, roller, or drum-be it of relatively major or minor significance-
can cause a rope to wear out many times faster than the wear resulting from normal
operations. As a positive means of minimizing abuses and other-than-normal wear, the
procedures here set forth should be adhered to. Every observation and measurement
should be carefully recorded and kept in some suitable and accessible file.
1. Give close examination to the method by which the rope is attached both to the drum
and to the load. Make certain that the proper means of attachment is applied
correctly, and that any safety devices in use are in satisfactory working order.
2. Carefully check the groove and working surface of every sheave, roller, and drum, to
determine whether each (groove and surface) is as near to the correct diameter and
contour as circumstances will permit, and whether all surfaces that are in contact with
the rope are smooth and free of corrugations or other abrasive defects.
3. Check sheaves and rollers to determine whether each turns freely, and whether they
are properly aligned with the travel of the rope. All bearings must be in good operating
condition and furnish adequate support to the sheaves and rollers. Sheaves that are
permitted to wobble will create additional forces that accelerate the deterioration rate
of the rope.
4. If starter, filler, and riser strips on drums are used, check their condition and location.
Should these be worn, improperly located or badly designed, they will cause poor
winding, dog legs, and other line damage.
5. Wherever possible, follow the path that the rope will follow through a complete
operating cycle. Be on the lookout for spots on the equipment that have been worn
bright or cut into by the rope as it moves through the system. Ordinarily, excessive
abrasive wear on the rope can be eliminated at these points by means of some type of
protector or roller.
FIELD LUBRICATION
During fabrication, ropes receive lubrication; the kind and amount depending on the rope’s
size, type, and anticipated use. This in-process treatment will provide the finished rope with
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