Lay of Wire Rope
ordinary lay (LHOL) wire rope
(close-up). Right-hand lay strands are
laid into a left-hand lay rope.
Lang's lay (RHLL) wire rope (close-up).
Right-hand lay strands are laid into a
right-hand lay rope.
The lay of a wire rope describes the manner
in which either the wires in a strand, or the
strands in the rope, are laid in a helix.
Left and right hand
Left hand lay or right hand lay describe the
manner in which the strands are laid to form the
rope. To determine the lay of strands in the
rope, a viewer looks at the rope as it points
away from them. If the strands appear to turn in
a clockwise direction, or like a right-hand
thread, as the strands progress away from the
viewer, the rope has a right hand lay. The
picture of steel wire rope on this page shows a
rope with right hand lay. If the strands appear
to turn in an anti-clockwise direction, or like
a left-hand thread, as the strands progress away
from the viewer, the rope has a left hand lay.
Ordinary, Lang's and
Ordinary and Lang's lay describe the manner
in which the wires are laid to form a strand of
the wire rope. To determine which has been used
first identify if left or right hand lay has
been used to make the rope. Then identify if a
right or left hand lay has been used to twist
the wires in each strand.
The lay of wires in each strand is
in the opposite direction to the lay
of the strands that form the wire.
The lay of wires in each strand is
in the same direction as the lay of
the strands that form the wire.
The lay of wires in the strands
alternate around the rope between
being in the opposite and same
direction to the lay of the strands
that form the wire rope.
Alternate term for ordinary lay.
Archaic term for Lang's lay.
Alternate term for alternate lay.
This is not a term used to classify
a lay as defined in this section. It
refers to a specific construction
type of wire rope.
the above example, each individual
wire is arranges around a central
wire to form a 7-wire strand. Six of
these strands are formed around a
central core to make a wire rope.
The rope is specified as 6x7 (6/1) –
i.e. six strands each of seven
The specification of a wire rope type –
including the number of wires per strand, the
number of strands, and the lay of the rope – is
documented using a commonly accepted coding
system, consisting of a number of abbreviations.
This is easily demonstrated with a simple
example. The rope shown in the figure "Wire rope
construction" is designated thus: 6x19 FC RH
||Number of strands that
make up the rope
||Number of wires that
make up each strand
||Right hand lay
||Flexible steel wire rope
Each of the sections of the wire rope
designation described above is variable. There
are therefore a large number of combinations of
wire rope that can be specified in this manner.
The following abbreviations are commonly used to
specify a wire rope.
Flexible steel wire rope
||Left hand lay
||Right hand lay
||Seale filler wire
||Safe working load
||Working load limit
RHOL wire rope terminated in a loop
with a thimble and talurit splice
The end of a wire rope tends to fray readily,
and cannot be easily connected to plant and
equipment. A number of different mechanisms
exist to secure the ends of wire ropes to make
them more useful. The most common and useful
type of end fitting for a wire rope is when the
end is turned back to form a loop. The loose end
is then fixed by any number of methods back to
the wire rope.
When the wire rope is terminated with a loop,
there is a risk that the wire rope can bend too
tightly, especially when the loop is connected
to a device that spreads the load over a
relatively small area. A thimble can be
installed inside the loop to preserve the
natural shape of the loop, and protect the cable
from pinching and abrasion on the inside of the
loop. The use of thimbles in loops is industry
best practice. The thimble prevents the load
from coming into direct contact with the wires.
Wire Rope Clamps (DOG
A wire rope clamp, also called a clip, is
used to fix the loose end of the loop back to
the wire rope. It usually consists of a u-shaped
bolt, a forged saddle and two nuts. The two
layers of wire rope are placed in the u-bolt.
The saddle is then fitted over the ropes on to
the bolt (the saddle includes two holes to fit
to the u-bolt). The nuts secure the arrangement
in place. Three or more clamps are usually used
to terminate a wire rope.
Swaging is a method of wire rope termination
that refers to the installation technique. The
purpose of swaging wire rope fittings is to
connect two wire rope ends together, or to
otherwise terminate one end of wire rope to
something else. A mechanical or hydraulic swager
is used to compress and deform the fitting,
creating a permanent connection. There are many
types of swaged fittings. Threaded Studs,
Ferrules, Sockets, and Sleeves a few examples.
A socket termination is useful when the
fitting needs to be replaced frequently. For
example, if the end of a wire rope is in a
high-wear region, the rope may be periodically
trimmed, requiring the termination hardware to
be removed and reapplied. An example of this is
on the ends of the drag ropes on a dragline. The
end loop of the wire rope enters a tapered
opening in the socket, wrapped around a separate
component called the wedge. The arrangement is
knocked in place, and load gradually eased onto
the rope. As the load increases on the wire
rope, the wedge become more secure, gripping the
|The ends of individual strands of
this eye splice used aboard a cargo ship
are seized with natural fiber cord after
the splicing is complete. This helps
protect seaman's hands when handling.
An eye splice may be used to terminate
the loose end of a wire rope when
forming a loop. The strands of the end
of a wire rope are unwound a certain
distance, and plaited back into the wire
rope, forming the loop, or an eye,
called an eye splice.