Pulling cable through conduit can be a high-anxiety job. “Large pulls of four or five cables can weigh up to 4,000 lbs. Even on these large pulls, there are several things contractors can do to make them quicker, safer and easier,” says Jim Eisele, product manager at Greenlee, a Textron company. Eisele outlines several ways you can simplify pulls:

USE QUALITY STANDS TO SUPPORT REELS.
Quality stands and spindles work together to help eliminate back strains, save set-up time, and minimize pulling problems from unruly reels. “Reels of cable can be extremely heavy,” says Eisele. “Contractors often build their own reel stands which require workers to lift the reel onto the stand. These reels can weigh 300 lbs. or
more. It makes sense to use stands that allow you roll the reel into position, then
jack up the reel with the stand so it can turn freely.” Contractors who use conduit as a spindle for home-built jack stands often have problems with the conduit sagging under the weight of the reel, which affects cable pulling. Also, as reels feed out and become lighter, the reel may jump off the stand during the pull. “When the reel
comes off the stand, pulling stops. It takes time to get the pull going again when this happens,” Eisele says.

SET STANDS CORRECTLY FOR EVEN FEEDING.
Reels feed best when they are set in line, but often, space constraints make that impossible. In these cases, stagger the reels in a double configuration or minimize the angle in which the cable must feed from the reels to the conduit.
Consider a cable feeder. Feeding cable is hard, heavy work, and exposes workers
to the dangers of back injuries or strains. “Besides, it’s a rather non-technical
task that usually involves journeymen electricians who could be putting their
training and talents to better use on the jobsite. That’s why cable feeding equipment
is growing in popularity,” he says. Relatively new to the market, these units help gather and bundle the wire as it feeds into the conduit. Result: you need
only two workers on the feeding side. “One worker applies lubricant and the
other controls the feeder. You don’t need a person on every cable pulling it off the
reel and one worker organizing it as it feeds into the conduit,” Eisele says.

SELECT THE RIGHT ROPE.
Using the wrong type of rope can greatly affect the safety and success of a wire pull. “Rope selection is critical,” says Eisele. “Know tensile strength, how friction affects it when used on a capstan and how much it will stretch. You don’t want a rope that stretches.” Ropes that stretch have stored energy that will be released if something breaks during the pull. That stored energy is like a stretched rubber band. If something snaps, the cable and rope can recoil and injure someone.
Eisele says double-braided composite rope is the best choice for pulling. It’s like
two ropes in one. “It’s a high-strength, low-stretch rope that has good characteristics on the capstan and in the conduit.” Polypropylene rope is often used for pulls, but its low melting point from friction and its high-stretch characteristic can
cause problems. “Polypropylene rope can get slipstick, which happens when the friction on the capstan actually melts the fibers of the rope and it sticks on the capstan. When there is enough tension to pull it free, it slips. It’s dangerous because it could pull your hand right into the capstan,” he says.
When you select a pulling rope, choose a type that has the capacity to handle four times the capacity of the puller you are using. “For example, if you are using a puller with a 6,500 lb. pulling capacity, you should use a rope with a 26,000 lb. capacity.”

WATCH THE ROPE.
During pulls, the worker on the front end of the system will
eventually have to contend with a pile of rope that’s already been pulled through the
conduit. “Always stand behind the pile of rope and never wrap the rope around your
wrist, waist, or feet. When operating the capstan, start with only two or three wraps
and increase wraps when the rope starts to slip. If you start with too many turns, you
don’t have good control,” he says.

MATCH COMPONENTS BASED ON PULLER CAPACITY, NOT WEIGHT OF WIRE PULL.

Like a chain, a pulling system is only as strong as its weakest link. But pullers often use components that are not rated to work together.“I have seen a lot of mixing and matching of component capacities during installations. The capacity of the puller
should drive all other component selection,” says Eisele. Sheaves, for example,
are often undersized for the forces they must exert. “If you are pulling a 2,000 lb.
pull 180 degrees over a 2,000 lb. capacity sheave, the actual load is 4,000 lbs.
You can eliminate figuring loads by making sure the equipment matches the
puller’s capacity,” he says. Similarly, make sure that mounting points for sheaves can withstand the heavy pulling forces. “Anchor to the solid structure, not to the tray or the ceiling grid,” he says.

SELECT THE RIGHT GRIP.
Wire grips are available in a basket type or a clamp type. Like sheaves, match the grip capacity to the puller capacity. “No matter what your pull weight is, components may get much more strain and the components must be able to take it,” Eisele says.

USE SHEAVES TO PROTECT CABLE.
This is very important when pulling wire through trays, says Eisele. “Any time the wire makes a turn, it should pass around a sheave. You use a sheave every 6 1/2’ for cable weighing greater than 2 lbs./ft. and every 10’ for cable weighing less than 2
lbs./ft.,” he says. Sheaves are also important in manhole pulls where the cable exits one conduit and enters another. “Use a sheave to help the cable easily enter the conduit on the other side of the manhole,” says Eisele. Puller Selection and Use Tips Eisele suggests you use the smallest puller capable for completing the job.
Smaller units pull faster than large capacity units, which can greatly affect how fast
you can get the job finished. Safety is another key component to puller selection. When looking at new equipment, look for safety features such as a right-angle sheave to get the operator out of the danger zone when pulling. Some models
have a capstan that has a rope ramp to prevent rope overlap. It’s also important to
have some sort of force-limiting device built into the puller. Consider how these
features make a pull more productive and help prevent accidents, he suggests.

MOUNT THE PULLER EFFECTIVELY.
If the puller must be mounted a distance from the conduit end to allow enough cable for wiring, use a floor mounting system that’s designed to take full advantage of the lead anchor you are using. “If you bolt only through the puller, the anchor bolts suffer tremendous bending forces. It’s best to use a mounting bracket that allows the anchors to be tightened completely into the concrete, then attach the puller to this bracket,” he says. Make sure the anchor is designed to withstand the forces
the puller will exert during the operation.

ESTABLISH EFFECTIVE COMMUNICATION.
Rarely can the puller operator see the workers feeding cable into the conduit.
“You must have effective communications at each end. Use walkie-talkies or radios to stay in contact,” he concludes.


_______________________________________________________________

Cable Pulling Rope Safety Tips from Greenlee
Rope is a very critical link in the cable pulling system. The following steps
should be observed in the selection and use of cable pulling rope.
1. Select a rope with an average breaking strength at least four times the rated capacity of your puller (rope safety factor). A safety factor of 4:1 minimum or greater than 4:1 is REQUIRED for pulling inside of raceways and conduit with a minimum of rope length exposed. Higher safety factors are recommended if the pulling rope is exposed! Required safety factors are for new rope in good condition without kinks or splices. When pulling, avoid sharp corners, edges, wedging or dragging over
rough ground. Dirt and grit picked up by the rope can work into the strands reducing
its pulling capacity. If there is any question, discard the used rope.
2. Use only low stretch double-braided polyester for high force cable pulling.
High stretch ropes store energy much like a stretched rubber band. If, for any reason, there is a failure of the rope, pulling grip, conductors, or any other component in the pulling system, this “stored-up” energy will suddenly be unleashed. The whipping action of a rope can cause considerable damage, serious injury or death.
3. Inspect rope thoroughly before using. Make sure there are no cuts or frays in
the rope. Remember the rope is only as strong as its weakest point. INSPECT
THOROUGHLY BEFORE USING!
4. When designing the pull, keep rope confined in conduit wherever possible.
Should the rope break, or any other part of the pulling system fail, releasing the
stored energy in the rope, the confinement in the conduit will work against the
whipping action of the rope by playing out much of this energy within the conduit.
5. Do not stand in direct line with the pulling rope. ❑