Inspecting Web Slings
All of our synthetic web
products are designed for long life under punishing conditions, but they will
eventually wear out after extended use. The key is knowing when to replace them,
and that's why it's very important to inspect your slings on a regular basis.
We've developed an inspection
program based on the procedure outlined in ANSI B30.9 that will make the most
of your investment. It's based on four sound beliefs:
The
importance of following regular and uniform inspections.
A
respect for the capabilities and limitations of synthetic web slings.
The
need to keep complete, permanent records.
Perhaps
most importantly, a lot of common sense.
The frequency of inspection
depends on three important factors:
Sling
usage - the more you use a sling, the more you need to inspect it.
The
working environment - the harsher the conditions, the more often you need to
inspect.
Sling
service life - based on your experience in using slings.
It's a good idea for the
person handling the slings to visually inspect all slings before each lift.
Additional inspections should be performed at least annually by a qualified
designated person and permanent records kept.
OSHA specifies, "Each day
before being used, the sling and all fastenings and attachments shall be
inspected for damage or defects by a competent person designated by the
employer. Additional inspections shall be performed during sling use, where
service conditions warrant." In other words, you should visually inspect
your sling before each lift.
Remove all slings,
including Flexi-Grip® round slings, from service if you see damage such as
the following, and return to service only when approved by a designated
person.
These are removal criteria
established by ANSI B30.9:
Acid
or caustic burns.
Melting
or charring of any part of the sling.
Holes,
tears, cuts or snags.
Broken
or worn stitching in load-bean~ng splices.
Excessive
abrasive wear.
Knots
in any part of the sling.
Excessive
pitting or corrosion, or cracked, distorted or broken fittings.
Other
visible damage that causes doubt as to the strength of the sling.
In addition, we recommend four
other important reasons to remove slings from service:
Anytime
you see our Red-Guard" warning yarns.
Distortion
of the sling.
Identification
tag that renders any part of it unreadable.
Anytime
a sling is loaded beyond its rated capacity for whatever reason.
While most of these standards
are very specific regarding reasons for removal, others require your good
judgment. The critical areas to watch are wear to the sling body, the selvage
edge of webbing and the condition of the sling eyes.
Web Repair Guidelines
It's never enough to give
slings temporary repairs. Always follow these guidelines:
1. Damaged slings should be
repaired only by a sling manufacturer.If that isn't possible, the repairman
should certify in writing the sling's rated capacity.
2. Slings repaired by a
manufacturer must be proof-tested to twice the designated rated capacity on
the tag before returning it to service and back it up with a certificate of
the proof-testing.
3. Inspection records for
individual slings that have been repaired should be updated with all the
relevant information such as the circumstances involved and proof-testing.
Our synthetic web products
don't merely meet our own strict standards for workmanship and performance.
They also meet or exceed these military and federal specifications:
ANSI
Standard 21.8 specifications of general requirements for a quality program.
2.
MIL-Standard-105 - sampling procedures and tables for inspection by
attributes.
3.
MIL-W-4088F - military specification for textile webbing woven nylon.
4.
MIL-W-23223A - military specification for slotted nylon webbing.
5.
Fed. Spec. VT-285-E - federal specification for polyester thread.
6.
Fed. Spec. VT-295-E - federal specification for nylon thread.
In addition, all work conforms
to standards established by the following national safety institutions and
their respective regulations:
American
National Standards Institute (ANSI) 830.9 Safety Standards for Cranes,
Derricks, Hoists, Hooks, Jacks and Slings.
Occupational
Safety and Health Administration (OSHA) 1910.184 Standards for Slings.
Identifying Web Sling
Wear and Abuse
These are some of the most
common types of web sling damage caused by abuse and misuse. When you see any
of these problems during your regular inspection, stop. Replace the sling
immediately because the damage is done. Never attempt to mend the sling
yourself and, more so, never attempt to lift with these slings.
Whether a sling is damaged
from improper use or normal wear, the same rule applies in all cases: always
cut the sling eyes and discard the sling right away when you see damage. Only
with properly working slings can you take a load off your mind.
Tensile break. The distinguishing sign of a
tensile break is a frayed appearance close to the point of failure or damage.
This usually happens when a sling is loaded beyond its existing strength. The
photo shows an example of a sling pulled to destruction on a testing machine.
You can avoid tensile breaks by never overloading your sling.
Cut. You can easily see a cut in your
sling when you see a clean break in the webbing structure or fibers. This
usually results when a sling contacts a sharp object or unprotected edge of a
load. This can happen anywhere on the sling body or eyes. Many slings feature
Red Guard warning yarns to alert you of serious cuts. One way you can avoid
cuts from contacting sharp corners is to use wear pads on the sling to
protect the fabric.
Cut and tensile
damage. A
good example is the photo shown here. It shows what can happen when you use a
sling that's already been cut by a sharp object along one edge of the sling
body. The cut dramatically reduces lifting capacity, and continued use will
ultimately lead to sling failure, usually at a load far below the sling's
rated capacity. The solution, obviously, is to never use a sling after it's
been cut.
Abrasion damage . Anytime you see frayed fibers on the
surface exposing the "picks," or cross fibers, of the webbing that
hold the load-bearing (lengthwise) fibers in place, it's abrasion damage. The
most common abrasion damage occurs either when the sling slips while in
contact with a load during a lift or when the sling is pulled from under a
load. When you see the Red Guard warning yarns exposed, it's your signal that
serious damage -- and loss of lifting capacity -- has occurred. We recommend
that slings with any damage to load-bearing fibers be discarded. Wear pads
are one way to avoid this damage.
Acid damage. It's true that nylon and
polyester webbing are stable when exposed to many common chemicals, but they
should never be exposed to any strong acids or corrosive liquids whenever
possible. The same is true for metal fittings on slings.
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