Manitowoc Published 10-01-2012, Control # 045-08 5-19
777 SERVICE MANUAL HOISTS
5
WIRE ROPE LUBRICATION
Refer to the Lubrication Guide supplied with your crane for
recommendations.
WIRE ROPE INSPECTION AND
REPLACEMENT
The inspection and replacement guidelines which follow
comply with United States regulations.
It is impossible to predict when a wire rope will fail; however,
frequent and periodic careful inspection by a qualified
inspector will indicate when the potential for failure exists.
Keeping Records
A signed and dated report of the wire rope’s condition at
each periodic inspection must be kept on file at all times. The
report must cover all inspection points listed in this section.
The information in the records can then be used to establish
data which can be used to determine when a wire rope
should be replaced.
It is recommended that the wire rope inspection program
include reports on the examination of wire rope removed
from service. This information can be used to establish a
relationship between visual inspection and the rope’s actual
internal condition at the time of removal from service.
Inspecting Wire Rope
Frequent Inspection
Visually inspect all running ropes in service once each work
shift and observe the rope during operation. Pay particular
attention to areas of the rope where wear and other damage
is likely to occur:
• Pick-Up Points — sections of wire rope that are
repeatedly stressed during each lift, such as those
sections in contact with sheaves.
• End attachments — the point where a fitting is attached
to the wire rope or the point where the wire rope is
attached to the drum.
• Abuse points — the point where the wire rope is
subjected to abnormal scuffing and scraping.
Inspect all rope which can be reasonably expected to be in
use during operation for obvious damage which poses an
immediate hazard, such as the following:
1. Rope distortion such as kinking, crushing, un-stranding,
bird caging, main strand displacement, and core
protrusion.
Loss of rope diameter and unevenness of the outer
strands indicate that the rope should be replaced.
2. Corrosion (clean and lubricate).
3. Broken or cut strands.
4. Broken wires (see Periodic Inspection for additional
information).
5. Core failure in rotation resistant rope (indicated by lay
lengthening and reduction in diameter).
Periodic Inspection
The periodic inspection interval must be determined by a
qualified inspector and be based on the following factors:
• Expected rope life as indicated by the rope manufacturer
or past experience as determined by the qualified
inspector.
• Severity of the environment the rope is operated in.
• Size, nature, and frequency of lifts.
• The rope’s exposure to shock loading and other abuse.
• Rope maintenance practices.
The periodic inspection must be performed at least annually.
During the periodic inspection, the entire length of wire rope
must be inspected for the following types of damage. Any
damage found must be recorded and a determination made
as to whether continued use of the rope is safe.
1. All points listed under frequent inspection.
2. Reduction in rope diameter below the nominal diameter
caused by loss of core support, internal or external
corrosion, or wear of the outside wires.
3. Severely corroded or broken wires at end attachments.
4. Severely corroded, cracked, bent, worn, or improperly
applied end attachments.
Rope Not In Regular Use
Wire rope must be given a complete inspection if it has been
idle for a month or more due to shutdown or storage of the
crane on which the rope is installed. The inspection must be
performed by a qualified inspector looking for the damage
identified under both Frequent and Periodic Inspection.
Replacing Wire Rope
The final decision as to when a wire rope should be replaced
is the responsibility of the qualified inspector. Discovery of
any of the following conditions is sufficient reason for
questioning a wire rope’s safety and for replacing it.
Wire Rope Diameter
Measure and record the diameter of a new wire rope after
initial loading for comparison with future inspections. A
reduction in rope diameter is often the first outward sign that
the wire rope core is damaged. When reduction in diameter
is noted, the rope must be removed from service.
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