Handling and Installation
Handling and Installation - Informational
RECEIVING, INSPECTION AND STORAGE
For all wire rope, the best time to begin taking appropriate care and handling measures is immediately
upon receiving it. On arrival, the rope should be carefully checked to make certain that the delivered product
matches the description on tags, requisition forms, packing slips, purchase order and invoice.
After these necessary preliminary checks, the next concern is that of providing weather-proof storage space.
If wire rope is to be kept unused for a considerable amount of time, it must be protected from the elements.
The idea storage area is a dry, well-ventilated building or shed. Avoid closed, unheated, tightly sealed
buildings or enclosures because condensation will form when warm, moist outside (ambient) air envelopes
the colder rope. Although wire rope is protected by lubricant, this is not totally effective since condensation
can still occur within the small interstices between strands and wires, thereby causing corrosion problems.
On the other hand, if the delivery site conditions preclude storage in an inside space and the rope must be
kept outdoors, it should be covered with a waterproof material. This covering will also prevent the lubricant
from drying out. Store the reel on an elevated platform or pallet that will keep it from direct contact with the
ground. Never store wire rope in areas subject to elevated temperatures. Dust and grit, or chemically laden
atmospheres should also be avoided. Although lubricant applied during manufacturing offers initial protection,
extended storage may require additional field lubrication.
Whenever wire rope remains on an idle machine, coat the rope with an appropriate protective lubricant. This
will provide additional protection against environmental conditions. If the wire rope is inactive for an extended
period while wound on the drum of the idle equipment, it may be necessary to apply a coating of lubricant to
each layer as the rope is wound on the drum. Cleaning, inspection and re-lubrication should precede start-up
of the equipment.
CHECKING THE DIAMETER
It is important to check the diameter of the delivered rope before installation. This is to make certain that the
rope meets the specified nominal diameter for the given application. Imperial (inch) and metric (millimeter)
ropes are not always interchangeable. Consult Horizon Cable for details on any specific rope diameter.
The actual rope diameter is the diameter of the circumscribing circle, i.e., its largest cross-sectional
dimension. To insure accuracy this measurement should be made with a wire rope caliper using correct
method (b) shown in the figure below. Special techniques and equipment must be employed for measuring
ropes with an odd number of outer strands (e.g. Circumferential taps, calipers and plates). Tolerance for wire
rope diameter permit the diameter to be slightly larger than the nominal size, according to the limits shown.
OVERSIZE LIMITS OF WIRE ROPE DIAMETERS*
*These limits have been adopted by the Wire Rope Technical Board. In case of certain special purpose ropes, such as aircraft
cables and elevator ropes, each has specific requirements. If a question should arise regarding compliance with oversize
tolerances, the rope may be measured under tension not exceeding 20% of the minimum breaking force. If the actual diameter
determined by this measurement is within the specified tolerance the rope is considered to meet the required diameter.
How to measure (or caliper) a wire rope correctly. Since the “true” diameter (A) lies within the circumscribed circle, always measure the larger dimension (B).
UNREELING AND COILING
Wire rope is shipped in cut lengths, either on coils or on reels. Great care should be taken when the rope
is removed from the shipping package since it can be permanently damaged by improper reeling or uncoiling.
Looping the rope over the head of the reel or pulling the rope off a coil while it is lying on the ground, will
create loops in the line. Pulling the loop will, at the very least, produce imbalance in the rope and may result
in open or closed kinks. Once a rope is kinked, the damage is not repairable. The kink must be cut out or
the rope is unfit for service.
Improper handling can create open (a) or closed kinks (b). The open kink will open the rope lay; the closed kink will close it.
Starting loop (c): Do not allow the rope to form a loop. If, however, a loop does form and is removed at the stage shown, a kink can be avoided. Kink (d): In this case, the looped rope was put under tension, the kink was formed, the rope is permanently damaged.
Unwinding wire rope from its reel also requires careful and proper procedure.
There are three methods to perform this step correctly:
1) The reel is mounted on a shaft supported by two jacks or a roller payoff. Since the reel is free to rotate,
the rope is puled from the reel by a workman holding the rope end, and walking away from the reel as it
unwinds. A braking device should be employed so that the rope is kept taut and the reel is restrained from
over-running the rope. This is necessary particularly with powered de-reeling equipment.
2) Another method involves mounting the reel on an unreeling stand. It is then unwound in the same manner
as described above. In this case, however, great care must be exercised to keep the rope under tension
sufficient to prevent accumulation of slack. Slack can allow the rope to drop over the rope coming off the reel
and be damaged or loose wraps on the reel to fall over the rope coming off the reel and become tangled.
3) In another accepted method, the end of the rope is held while the reel itself is rolled along the ground.
With this procedure, the rope will pay off properly however, the end being held will travel in the direction the
reel is being rolled. As the difference between the diameter of the reel head and the diameter of the wound rope
increase, the speed of travel will increase.
The wire rope reel is mounted on a shaft supported by jacks. This permits the reel to rotate freely, and the rope can be unwound either manually or by a powered mechanism.
When re-reeling wire tope from a horizontally supported reel to a drum it is preferable for the rope to travel
from the rope of the reel to the drum; or, from the bottom of the reel to the bottom of the drum. Re-reeling
in this manner will avoid putting a reverse bend into the rope during installation. If a rope is installed so that
a reverse bend is induced, it may cause the rope to become ‘twisty’ and, consequently, harder to handle.
The correct (a) and the wrong (b) way to wind wire rope from reel to drum.
When unwinding wire rope from a coil, there are two suggested methods for carrying out this procedure in
a proper manner;
1) One method involves placing a coil on a vertical unreeling stand. The stand consists of a plate with a fixed
vertical shaft. On this shaft there is a “swift”, consisting of a plate with inclined pins positioned so that the coil
may be placed over them. The whole swift and coil then rotate as the rope is pulled off. This method is
particularly effective when the rope is to be wound on a drum.
2) The most common as well as easiest uncoiling method is merely to hold one end of the rope while rolling
the coil along the ground like a hoop. The first two figures below show unreeling methods that are most
likely to cause kinks. Such improper procedures must be avoided in order to prevent the occurrence of loops.
These loops, when pulled taut, will inevitably result in kinks. No matter how a kink develops, it will damage
strands and wires, and the kinked section must be cut out. Proper and careful handling will keep the wire
rope free from kinks.
Perhaps the most common and easiest uncoling method is to
Illustrating a wrong method of unreeling wire rope.
Illustrating a wrong method of uncoiling wire rope.