Figure 6-55.Wire rope clips.
U-bolt on the bitter (dead) end, not on the standing part
of the wire rope. If clips are attached incorrectly, the
standing part (live end) of the wire rope will be
distorted or have mashed spots. A rule of thumb when
attaching a wire rope is to NEVER saddle a dead horse.
Two simple formulas for figuring the number of
wire rope clips needed are as follows:
3 x wire rope diameter + 1 = Number of clips
6 x wire rope diameter = Spacing between clips
Another type of wire rope clip is the twin-base
clip, often referred to as the universal or two clamp
(fig. 6-56). Both parts of this clip are shaped to fit the
wire rope, so the clip cannot be attached incorrectly.
The twin-base clip allows for a clear 360-degree swing
with the wrench when the nuts are being tightened.
THIMBLE.When an eye is made in a wire rope,
a metal fitting, called a thimble, is placed in the eye, as
shown in figure 6-55. The thimble protects the eye
against wear. Wire rope eyes with thimbles and wire
rope clips can hold approximately 80 percent of the
wire rope strength.
After the eye made with clips has been strained, the
nuts on the clips must be re-tightened. Checks should
be made now and then for tightness or the clips will
cause damage to the rope.
SWAGED CONNECTIONS.Swaging makes
an efficient and permanent attachment for wire rope, as
shown in figure 6-57. A swaged connection is made by
compressing a steel sleeve over the rope by using a
hydraulic press. When the connection is made
properly, it provides 100 percent capacity of the wire
Careful inspection of the wires leading into these
connections is important because of the pressure put
upon the wires in this section. If one broken wire is
found at the swaged connection or a crack in the swage,
replace the fitting.
HOOKS AND SHACKLES.Hooks
shackles are handy for hauling or lifting loads without
tying them directly to the object with line, wire rope, or
chain. They can be attached to wire rope, fiber line,
blocks, or chains. Shackles should be used for loads
too heavy for hooks to handle.
When hooks fail due to overloading, they usually
straighten out and lose or drop their load. When a hook
has been bent by overloading, it should NEVER be
straightened and put back into service. It should be cut
in half with a cutting torch and discarded.
Hooks should be inspected at the beginning of
each workday and before lifting a full-rated load. If
you are not sure a hook is strong enough to lift the load,
by all means use a shackle.
Hooks that close and lock should be used where
there is a danger of catching on an obstruction,
particularly in hoisting buckets, cages, or skips, and
especially in shaft work. Hooks and rings used with a
chain should have about the same strength as the chain.
Figure 6-57.Swaged connections.
Figure 6-56.Twin-base wire rope clip.