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SLINGS
WIRE ROPE
WIRE ROPE SLING INSPECTION AND REMOVAL CRITERIA
BASIC INSPECTION CRITERIA FOR WIRE ROPE
internal lubricant caused by exposure to heat.
SLINGS
The goal of a sling inspection is to evaluate remaining
5. Bad End Attachments: Cracked, bent or broken end fit
strength in a sling which has been used previously to
tings caused by abuse, wear or accident.
determine if it is suitable for continued use.
6. Bent hooks: No more than 15 percent over the normal
The specific inspection intervals and procedures are
throat openings, measured at the narrowest point, or twist
required by the Occupation Safety and Health Act (OSHA)
ing more than 10 degrees is permissible.
and by ANSI B30.9 Regulations, and the responsibility for
performance of inspections is placed squarely upon the
7. Metal Corrosion: Severe Corrosion of the rope or end
sling user by Federal Legislation.
attachments which has caused pitting or binding of wires
should be cause for replacing the sling. Light rusting usu
As a starting point, the same work practices which apply to
ally does not affect strength of a sling, however.
all working wire ropes apply to wire rope which has been
fabricated into a sling. Therefore, a good working knowl
In addition to these seven conditions specified by OSHA,
edge of wire rope design and construction will be not only
the following are also important:
useful but essential in conducting a wire rope sling inspec
tion.
8. Pulled Eye Splices: Any evidence that they eye splices
have slipped, tucked strands have moved, or pressed
Because wire rope is a rather complex machine, no pre
sleeves show serious damage may have sufficient cause
cise rules can be given to determine exactly when a wire
to reject a sling.
rope sling should be replaced. There are many variables,
and all must be considered.
9. Unbalance: A very common cause of damage is the
kink which results from pulling through a loop while using a
OSHA specifies that a wire rope sling shall be removed
sling, thus causing wires and strands to be deformed and
from service immediately if ANY of the following conditions
pushed out of their original position. This unbalances the
are present:
sling, reducing it's strength.
1. Broken Wires: For sing part slings, 10 randomly distrib
Disposition of Retired Slings: the best inspection program
uted broken wires in one rope lay, or five broken wires in
available is of no value if slings which are worn out an
one strand of one rope lay. For multi part slings these
have been retired are not disposed of properly. when it is
same criteria apply to each of the component ropes. For
determined by the inspector that a sling is worn out or
this inspection, a broken wire shall only be counted once;
damaged beyond use, it should be tagged immediately DO
that is, each break should have two ends.
NOT USE.
2. Metal Loss: Wear or scraping of one third the original
this sling should then be destroyed as soon as possible by
diameter of outside individual wires. This is quite difficult
cutting the eye an fittings from the rope with a torch. This
to determine on slings an experience should be gained by
will help assure that an employee will not mistakenly use a
the inspector by taking apart old slings and actually meas
sling which has been retired from service.
uring wire diameters.
It should also be obvious that a good inspection program
3. Distortion:Kinking, crushing, birdcaging or other dam
will not only provide safer lifting conditions, but will also
age which distorts the rope structure. The main thing to
extend the life of the slings and thereby reduce lifting
look for is wires or strands that are pushed out of their
costs.
original positions in the rope. Slight bends in a rope where
wires or strands are still relatively in their original positions
FEDERAL WORK RULES REQUIRE SPECIFIC
would not be considered serious damage. But good judg
INSPECTION INTERVALS
ment is indicated.
Government regulations are also specific on WHEN to
4. heat Damage: Any metallic discoloration or loss of
inspect.
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