Wire rope inspection
A
ll wire ropes will wear out HOW OFTEN
eventually and gradually lose All wire ropes should be thoroughly
work capability throughout inspected at regular intervals. The longer
their service life. That’s why periodic it has been in service or the more severe
inspections are critical. Applicable the service, the more thoroughly and
industry standards such as ASME frequently it should be inspected.
B30.2 for overhead and gantry cranes Be sure to maintain records of each
or federal regulations such as OSHA inspection.
refer to specific inspection criteria
for varied applications. APPOINT A QUALIFIED PERSON
TO INSPECT
THREE PURPOSES FOR INSPECTION Inspections should be carried out by a
Regular inspection of wire rope and person who has learned through special
equipment should be performed for training or practical experience what
INSPECT YOUR to look for and who knows how to
three good reasons:
WIRE ROPE
REGULARLY
judge the importance of any abnormal
> It reveals the rope’s condition and conditions they may discover. It is the
> Inspection should
indicates the need for replacement. inspector’s responsibility to obtain and
be performed by a
follow the proper inspection criteria for
person with special
> It can indicate if you’re using the each application inspected.
training or practical
experience. most suitable type of rope.
For information on inspection methods and
> It makes possible the discovery and techniques, our Techreport 107: Wire Rope
correction of faults in equipment Inspection, is available on the unionrope.
or operation that can cause costly com website for download. If you need
accelerated rope wear. further assistance with our ropes, contact
our Product Engineering Department.
www.unionrope.com
Wire rope inspection
WHAT TO LOOK FOR
Here’s what happens when a wire
This is an example of fatigue failure of
breaks under tensile load exceeding
a wire rope subjected to heavy loads
its strength. It’s typically recognized by
over small sheaves. The breaks in
the “cup and cone” appearance at the
the valleys of the strands are caused
point of failure. The necking down of
by “strand nicking.” There may be
the wire at the point of failure to form
crown breaks, too.
the cup and cone indicates failure has
occurred while the wire retained its
ductility.
Here you see a single strand removed
This is a wire with a distinct fatigue from a wire rope subjected to strand
break. It’s recognized by the square nicking. This condition is a result
end perpendicular to the wire. This of adjacent strands rubbing against
break was produced by a torsion one another. While this is normal in a
machine that’s used to measure the rope’s operation, the nicking can be
ductility. This break is similar to wire accentuated by high loads, small
failures in the field caused by fatigue. sheaves or loss of core support. The
ultimate result will be individual wire
breaks in the valleys of the strands.
Shown here is a wire rope that has
been subjected to repeated bending
over sheaves under normal loads. This
results in fatigue breaks in individual
wires – these breaks are square and
usually in the crown of the strands.
Form No. 1179
ph: +1.816.270.4700 | info@wirecoworldgroup.com | www.unionrope.com
