5SSSSS35 (b) WRONG
Funjan SO.—Long spile«, be protected by a coating of lubricant Wire in use should be well lubricated.
d. Newly installed wire rope should be worked for a while without load to enable rope to adjust itself to working conditions.
e. To avoid sharp kinks, all loops in slack rope should be straightened before load is applied. To remove a kink, wire
). Loads must not be applied suddenly. This puts excessive strain on rope.
g. Avoid using wire rope on sheaves or drums which are too small, and avoid reverse bends or sudden changes in direction of pull. Either oi these conditions causes severe strain and broken wires in strands and weakens rope.
h. It is best to wind only a single layer of rope on drums; however, If necessary to wind more layers, second layer is wound on grooves formed by first, except that once in each turn rope crosses over two sections of first layer. Third layer is parallel to first layer and wound on grooves of second, except at crossovers. In all cases when it is expected to wind a second layer, the turns of first layer must be wound together tightly to prevent possible binding.
i. Ropes should not be pulled around small trees or flat surfaces. This causes strands to spread.
1. Distance between hoisting drum and first sheave should be not less than 15 feet per foot of drum width. Distances shorter than thl3 cause excessive rope abrasion.
k. When removing wire rope from reel or coil, reel or coll must rotate as the rope unwinds. Attempts to unwind rope from stationary coils will result In kinking.
(11 A correct method for unreeling wire rope is to mount reel on a shaft supported at each end. Rope is then pulled off, permitting reel to rotate. When spooling wire rope from reel to drum, rope should travel from top of reel to top of drum, or from bottom of reel to bottom of drum. This prevents reverse bends which make rope difficult to handle.
(2) To uncoil wire rope, end Is held stationary while coil Is rolled out on ground. This method prevents kinks.
I When coiling wire rope loose as it comes from drum, determine lay of rope; if left lay, coil to left (counterclockwise), or if right lay. coil to right (clockwise). When finished, ends of rope should be tied to coil, and top or end should be marked to aid in uncoiling.
m. To wind wire rope on reel or drum, the following rule
Is convenient to determine proper starting flange; the left
45 27-28 hand Is used for left-lay rope, and the right hand for right-lay rope; back of the hand is up for overwinding and down for unwinding. Standing behind and facing drum, the fist represents the drum, and the extended index finger, the rope leading away from drum; thumb Indicates at which flange rope should start. Thus, for a left-lay rope overwinding, back of left hand is up. index Anger points along rope leading away from drum, and thumb to right indicates that rope should be started on right-hand flange.
n. To avoid accidents, every reasonable effort should be made to stand clear of any wire rope under tension.
o. When rope used on drums and sheaves has had approximately half of its normal use, ends should be reversed to change points of wear.
■ 28. Lashings amu Spars.—a. Square lashing (two spars at right angles) (see fig. 52).—To lash two spars at right angles make a clove hitch around the upright a few inches above the transom. Bring the lashing under the transom, up in front of It, horizontally behind the upright, down in front of the transom, and back behind the upright at the level or the bottom of transom and above the clove hitch. Keep the following turns outside the previous ones on one spar and inside on the other, not riding over the turns already made. Make four more turns. Make two Trapping turns between the spars, around the lashing, and finish the lashing off either around one of the spars or any part of the lashing through which the rope can be passed. Do not make the final clove hitch around the spar on the side toward which the stress is to come, as it may Jam and be difficult to remove. While tightening, beat the lashing with a handspike or pick handle.
b. Three spars for tripod (see fig. 52).—<1) To lash three spars together as for a gin or tripod, mark on each spar the location of the center of the lashing. Lay two of the spars parallel to each other with an interval a little greater than the diameter. Rest their tips on a skid and lay the third spar between them with its butt in the opposite direction, bo that the marks on the three spars will be in line. Make a clove hitch on one of the outer spars about 4 inches above
46 28 the lashing mark, and take eight or nine loose t;;ris around the three spars. Take a couple of frapping turns between each pair of spars In succession and finish with a clove hitch on the central spar above the lashing. Pass a sling over the lashing and the tripod Is ready for raising.
t2) Figure 52 also illustrates an alternate method for lashing three poles together for a tripod c. Pair of shears (fig. 53).—To lash for a pair of shears, lay the two spars alongside each other with the butt ends near the place where they are to be erected; rest the points below which the lashing la to be made on a skid. Make a clove hitch around one spar and take the lashing loosely eight or nine turns about the two spars, above the clove hitch, without riding. Make two or more trapping turns between the spars, and finish the lashing off with a clove hitch below the turns on the other spar. Open the butts of the spars and pass a sling over the fork. Hook or lash a block to this sling. Make fast fore and back guys with clove hitches to each spar just above the fork, so that the rear guy pulls on the front leg and the front guy, the rear leg.
d. Gin pole,—A gin pole is used to handle heavy loads. The pole should be no longer than 60 times its smallest diameter; otherwise the pole may buckle under a load.
(1) Rigging a gin pole (fig. 54).—Lay the pole on the ground with the base (large end) at the spot where the pole is to be erected. Make a tight lashing of eight or nine turns about 1 foot from the top of the pole; with two or more of the central turns engage the hook of the upper hoisting block. Nail cleats to the pole to prevent the lashing from sliding down the pole. Attach the guy lines with a clove hitch Just above the tackle lashing, and nail cleats to the pole just above the guy lines to prevent their slipping off. Lash a block to the butt of the pole about 2 feet above the base in the same manner as at the top of the pole. Now reeve the hoisting tackle.
<2) Erection (fig. 54).—Dig a hole where the base of the pole is to rest and anchor the base to prevent its slipping when
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