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the weather. The outside layers of the rope should be coated with a good lubricant that is as nearly moisture-proof as can be obtained.

Wire rope should be handled carefully while on a reel or coiled as it comes from the manufacturer. Reels containing wire rope should never be dropped from a car or truck in unloading or moved by prying against the coiled rope; the bearing always should be against the reel.

Avoiding kinks.-It is very important to uncoil a wire rope in such a manner as to avoid kinks. The reel should be mounted on a support that permits it to rotate as the rope is drawn off. Attempts to unwind the rope from stationary coils or reels will result in kinking the rope, and once a kink is formed, the rope at that point is very greatly weakened; in fact, it is very likely to be ruined beyond repair (fig. 16).

A rope received from the manufacturer in a coil in place of on a reel should be unwound by holding the loose end and rolling the coil on the ground like a hoop. Any other method of uncoiling is very likely to result in a kink (fig. 17).

Effects of kinks.-A kink in a wire rope distorts the relation of the strands and the wires making up the strands, causing unequal stresses in the strands at that point. The short life of ropes often can be

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FIGURE 18.-A, The loop-where the danger of a left kink begins; B, the result-a left kink.

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A

B

FIGURE 19.-A, Typical result of right kink in right-lay, regular-lay rope; B, typical wire rope. result of left kink in right-lay, regular-lay rope; C, enlarged view of result of kink in

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FIGURE 20.-A, Deep groove cut in sheave by wire rope (note strand corrugation in metal will not fit in groove. surface); B, a worn rope has made such a deep groove in this sheave that a new rope

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