The first small letters z, s mean the direction of lays in the rope. The direction of wires in the strands – left, right – is respectively designated with characters Z and S following the character describing the direction of lays in the rope.

The co-related directions arrangement in the strands and the rope is designated as follows:

    1) Left lang (LL) – The direction of wires in the lay and lays in the rope is left, the arrangement is designated sS
    2) Right lang (RL) – The direction of wires in the lay and lays in the rope is right, the arrangement is designated zZ
    3) Left regular (LR) – The direction of wires in the lay is right and the lays in the rope is left, the arrangement is designated zS
    4) Right regular (RR) – The direction of wires in the lay is left and the lays in the rope is right, the arrangement is designated sZ



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A simple method of determining how a wire rope should be started on a drum is shown in the above diagram. The observer stands behind the drum, with the rope coming towards him. Using the right hand for right-lay wire rope, and the left hand for left lay wire rope, the clenched fist denotes the drum, the extended index finger the oncoming rope.




Unreeling & Uncoiling


The Right Way to Unreel. To unreel wire rope from a heavy reel, place a shaft through the center and jack up the reel far enough to clear the floor and revolve easily. One person holds the end of the rope and walks a straight line away from the reel, taking the wire rope off the top of the reel. A second person regulates the speed of the turning reel by holding a wood block against the flange as a brake, taking care to keep slack from developing on the reel, as this can easily cause a kink in the rope. Lightweight reels can be properly unreeled using a vertical shaft; the same care should be taken to keep the rope taut.

The Wrong Way to Unreel. If a reel of wire rope is laid on its flange with it's axis vertical to the floor and the rope unreeled by throwing off the turns, spirals will occur and kinks are likely to form in the rope. Wire rope always should be handled in a way that neither twists nor unlays it. If handled in a careless manner, reverse bends and kinks can easily occur.

The Right Way to Uncoil. There is only one way to uncoil wire rope. One person must hold the end of the rope while a second person rolls the coil along the floor, backing away. The rope is allowed to uncoil naturally with the lay, without spiraling or twisting. Always uncoil wire rope as shown.

The Wrong Way to Uncoil. If a coil of wire rope is laid flat on the floor and uncoiled by pulling it straight off, spirals will occur and kinking is likely. Torsions are put into the rope by every loop that is pulled off, and the rope becomes twisted and unmanageable. Also, wire rope cannot be uncoiled like hemp rope. Pulling one end through the middle of the coil will only result in kinking.

Kinks
Great stress has been placed on the care that should be taken to avoid kinks in wire rope. Kinks are places where the rope has been unintentionally bent to a permanent set. This happens where loops are pulled through by tension on the rope until the diameter of the loop is only a few inches. They are also caused by bending a rope around a sheave having too severe a radius. Wires in the strands at the kink are permanently damaged and will not give normal service, even after apparent "restraightening."

Drum Winding. When wire rope is wound onto a sheave or drum, it should bend in the manner in which it was originally wound. This will avoid causing a reverse bend in the rope. Always wind wire rope from the top of the one reel onto the top of the other. Also acceptable, but less so, is rereeling from the bottom of one reel to the bottom of another. Re-reeling may also be done with reels having their shafts vertical, but extreme care must be taken to ensure that the rope always remains taut. It should never be allowed to drop below the lower flange on the reel. A reel resting on the floor with its axis horizontal may also be rolled along the floor to unreel the rope.

Wire rope should be attached at the correct location on a flat or smooth-faced drum, so that the rope will spool evenly, with the turns lying snugly against each other in even layers. If wire rope is wound on a smooth-face drum in the wrong direction, the turns in the first layer of rope will tend to spread apart on the drum. This results in the second layer of rope wedging between the open coils, crushing and flattening the rope as successive layers are spooled.

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Regular lay denotes rope in which the wires are twisted in one direction, and the strands in the opposite direction to form the rope. The wires appear to run roughly parallel to the center line of the rope. Due to the difference in direction between the wires and strand, regular lay ropes are less likely to untwist or kink. Regular lay ropes are also less subject to failure from crushing and distortion because of the shorter length of exposed outer wires.

Lang lay is the opposite; the wires and strands spiral in the same direction and appear to run at a diagonal to the center line of the rope. Due to the longer length of exposed outer wires, lang lay ropes have greater flexibility and abrasion resistance than do regular lay ropes. Greater care, however, must be exercised in handling and spooling lang lay ropes. These ropes are more likely to twist, kink and crush than regular lay ropes.

Right or left lay refers to the direction in which the strands rotate around the wire rope. If the strands rotate around the rope in a clockwise direction (as the threads do in a right hand bolt), the rope is said to be right lay. When the strands rotate in a counterclockwise direction (as the threads do in a left hand bolt), the rope is left lay.

Right regular lay is furnished for all rope applications unless otherwise specified.

When a lay-length is used as a unit of measure, it refers to the linear distance a single strand extends in making one complete turn around the rope. Lay-length is measured in a straight line parallel to the center line of the rope, not by following the path of the strand. The appropriate time to replace a wire rope in service is frequently determined by counting the number of broken wires in the length of one rope lay.

    single-layer drums = ordinary lay ropes
    multi-layer drums = lang's lay ropes

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Generally the rope fleet angle causes the rope to not wind to its lowest point but
instead the sheave first touches an edge and then rolls into the bottom of the
groove. This so-called "forced torsion of the rope" increases with the fleet angle.
The authoritative ISO standard 16625 limits the fleet angle to 4° for non-rotation-
resistant ropes and 2° for rotation-resistant and low rotation ropes. This narrow
restriction for low rotation and rotation-resistant ropes results from the fact that
ropes with steel cores closed in the opposite direction respond more sensitively to
forced torsion than conventional ones.

Lateral deflection can of course arise during rope installation. Here, the specified
maximum fleet angle from ISO 16625 must also be complied with to prevent
twisting developing during rope installation. The fleet angle can be minimised by
establishing as large a distance as possible between the reel and drum or head
pulley sheave.

"A wire rope counts as non-rotating if the twist angle rests smaller than 360°, considering a length L of
1000 times d, during the tensile loading S/d² between 0 to 150 N/mm²."
Where: S: load
d: rope diameter
L=1000*d: considered length