Torin T32052, Руководство пользователя

Страница: 12 / 58

12
REMOVING CABLE
Removing old cable involves the same principles as installing new cable. However, there are some important
differences.
Pulling Force
It is difficult to predict the amount of pulling force necessary to remove an old cable. The cable may be
damaged, and it may break with an unexpectedly low pulling force.
The required pulling forces may be very high:
• The cable has probably “taken a set.” Unlike the new cable on a reel, cable in conduit has probably been in
the conduit for years, or perhaps decades. The cable will resist bending and straightening as it is pulled
through the conduit.
• The pulling lubricant has probably hardened, increasing pulling resistance.
• The insulation may be damaged and the cable may be corroded.
• Dirt or other foreign matter may have entered the conduit and may have cemented the cable in place.
Using a Force Gauge
When pulling old cable out of a conduit, the pulling force will be highest when starting the pull. Select a cable
puller and pulling components to meet or exceed the estimated amount of pulling force necessary to remove
the old cable. Because breaking the cable free will require the largest amount of pulling force,do not exceed
overloading the system components.
Carefully monitor the pulling force; if the puller is not able to begin the pull, start over with a puller and
components of a higher force rating.
Puller Placement
Pulling out old cable is generally accomplished with the puller located some distance away from the end of
the conduit. This allows the you to pull out a long section of cable before, cutting off the cable, and reattaching
the grip(s). Mounting the cable puller a distance away from the end of the conduit increases the amount of
exposed rope, which greatly increases the amount of violent whipping action which would occur if the rope
were to break.
To isolate the operator from the rope path:
• Locate the puller so that you will stand behind an obstruction, such as a wall. Set up the puller so that you
will be able to maintain control of the pull. You need a clear view of the rope as it feeds onto the capstan,
including several feet of the rope in front of the capstan.
You must be able to turn off the puller before the pulling grip, connector, or swivel contacts the capstan.
• Use an additional pulling sheave (if necessary) to change the direction of the tailing rope. Anchor the sheave
so that you are close enough to maintain control of the pull. You need a clear view of the rope as it feeds
onto the capstan, including several feet of the rope in front of the capstan. You must be able to stop the
puller before the pulling grip, connector, or swivel contacts the capstan.
Note: Use an additional pulling sheave to change the direction of the tailing rope (after the rope leaves the
capstan). Do not change the direction of the pulling rope.
• Locate the puller so that you will stand behind an obstruction, such as a wall. Set up the puller so that you
will be able to maintain control of the pull. You need a clear view of the rope as it feeds onto the capstan,
including several feet of the rope in front of the capstan. You must be able to turn off the puller before the
pulling grip, connector, or swivel contacts the capstan.
• Use an additional pulling sheave (if necessary) to change the direction of the tailing rope. Anchor the sheave
so that you are close enough to maintain control of the pull. You need a clear view of the rope as it feeds
onto the capstan, including several feet of the rope in front of the capstan. You must be able to turn off the
puller before the pulling grip, connector, or swivel contacts the capstan.
Note: Use the additional pulling sheave to change the direction of the tailing rope (after the rope leaves the
capstan). Do not change the direction of the pulling rope.
• Use a longer tailing rope than usual and stand away from the puller. Stand as far from the puller as
possible, while maintaining control of the pull. You need a clear view of the rope as it feeds onto the capstan,
including several feet of the rope in front of the capstan. You must be able to turn off the puller before the
pulling grip, connector, or swivel contacts the capstan.