Figure 5-18. - Swage gauge.
Figure 5-19. - Lap splice using a nicopress oval sleeve.
space should be maintained between the two sleeves, as shown. The lap splice should be tested before being used.
To render safe, dependable service over a maximum period of time, you should take good care and upkeep of the wire rope that is necessary to keep it in good condition. Various ways of caring for and handling wire rope are listed below.
Once anew reel has been opened, it may be coiled or faked down, like line. The proper direction of coiling is counterclockwise for left lay wire rope and clockwise for right lay wire rope. Because of the general toughness and resilience of wire, it often tends to resist being coiled down. When this occurs, it is useless to fight the wire by forcing down the turn because the wire will only spring up again. But if it is thrown in a back turn, as shown in figure 5-20, it will lie down proper] y. A wire rope, when faked down, will run right off like line; but when wound in a coil, it must always be unwound.
Wire rope tends to kink during uncoiling or unreeling, especially if it has been in service for a long time. A kink can cause a weak spot in the rope that wears out quicker than the rest of the rope.
A good method for unreeling wire rope is to run a pipe, or rod, through the center and mount the reel on drum jacks or other supports, so the reel is off the ground (fig. 5-21, view A). In this way, the reel will turn as the rope is unwound, and the rotation of the
Figure 5-20. - Throwing a back turn.
reel helps keep the rope straight. During unreeling, pull the rope straight forward and avoid hurrying the operation. As a safeguard against kinking, NEVER unreel wire rope from a reel that is stationary.
To uncoil a small coil of wire rope, simply stand the coil on edge and roll it along the ground like a wheel, or hoop (fig. 5-21, view B). NEVER lay the coil flat on the floor or ground and uncoil it by pulling on the end because such practice can kink or twist the rope.
One of the most common types of damage resulting from the improper handling of wire rope is the development of a kink. A kink starts with the formation of a loop (fig. 5-22).
A loop that has not been pulled tight enough to set the wires, or strands, of the rope into a kink can be removed by turning the rope at either end in the proper direction to restore the lay, as shown in figure 5-23. If this is not done and the loop is pulled tight enough to cause a kink (fig. 5-24), the kink will result in irreparable damage to the rope (fig. 5-25).
Kinking can be prevented by proper uncoiling and unreeling methods and by the correct handling of the rope throughout its installation.
Whenever possible, drums, sheaves, and blocks used with wire rope should be placed to avoid reverse or S-shaped bends. Reverse bends cause the individual wires or strands to shift too much and increase wear and fatigue. For a reverse bend, the drums and blocks affecting
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