Technical Information

Lays of Wire Rope

   

Right Hand Regular Lay

Left Hand Regular Lay

 

Right Hand Lang's Lay

Left Hand Lang's Lay

Right hand regular lay rope

A standard wire rope is a right hand regular lay rope composed of six strands laid around a core. This is the type of rope that is most commonly furnished unless otherwise specified or indicated. In this rope, the individual wires of the strand have been laid in a left hand direction and the strands themselves have been laid in a right hand direction around the core of the rope. This rope is easily identified through the individual wires, as they appear on the surface of the rope, and are parallel to the axis of the rope. The strands appear as a right hand thread.

Left hand regular lay wire rope

If the individual wires of the component strands have been laid in a right hand direction and the strands have been laid in a left hand direction around the core of the rope,the rope is a left hand regular lay wire rope. Here again, the individual wires on the surface of the rope are parallel to the axis of the rope, but the strands appear as a left hand thread.

Right hand Lang lay

Right hand Lang lay wire rope is one in which the individual wires of the strand have been laid in a right hand direction and the strands themselves have been laid in a right hand direction around the core of the rope. The individual wires, as they appear on the surface of the rope, create an angle with the axis in the same general direction as the strands themselves, appearing as a right hand thread. Lang lay rope is composed of six strands around a core and has many uses, particularly in construction and mining applications. It is more flexible and has a greater abrasion resistance, due to the greater length of wire exposed to wear than an ordinary lay rope of the same strength, grade, and construction.

Left lay Lang lay rope can be manufactured,  but has a very limited application and is rarely used.

Length of lay:

Each strands in a wire rope is helical in shape. The distance measured parallel to the axis or the centre line of a rope in which the strand makes one complete spiral around the rope, is the length of rope lay.



The length of the helix of the individual wires in the strands may also vary. This length is measured in the same manner as rope lay and is referred to as strand lay.

Preforming :

Preforming is the process in which each individual strand permanently formed in the helical shape, will assume in the finished wire rope. This process causes the strands to lay in place and removes the tendency of wires and strands to fly apart when cut.

There are many advantages of Preformed wire rope, some of which are as follows:

  • Preformed wire rope will not unravel when seizing is removed.
  • Preformed wire rope is better able to resist severe bending conditions.
  • Preformed wire rope tends to hold onto small drums better than non-preformed ropes and winds more uniformly.
  • Preformed rope is more inert than non-preformed rope, which makes it easier to install and less susceptible to the formation of kinks.

 

The Structure of wire rope may be analyzed as follows.

SIZE :

Generally denoted by its diameter, it is equal to the diameter of the circle which will completely enclose the rope. Denoted by inch(‘) or millimeter (mm).

 

 

 

Strand formation : It is the number of strands in a rope, as well as the numbers and arrangement of wires in a strand.

Example – 6 (=No. of strands) X 19 (12/6/1) (=No. and arrangement of wires in the strand)


The majority of wire ropes are composed of strands with symmetrical cross sections that fit smoothly into a circumscribed circle, which are made of round wires.

The following basic designs are used:

Single layer formation : In this design, the outer wires are wound around a centre wire.

 

 

 

Seale formation: In this design, the outer layer has a predetermined number of large wires. They are laid around an equal number of small inner wires in such a manner that the outer wires lie in the valley of the under-lying wires. The advantage of this is in its more abrasive surface.

 

 

Multiple layer formation: In this design, there is more than one operation. The layers are formed one over the other in succession. It is a straight formation and equal sizes of wires are used.

 

 

Filler formation: In this design, an even number of wires are laid around an inner layer of half that number. In each valley between two layers, a small wire is filled. The advantage of this construction is in its greater strength and shock absorption capacity as a result of compact design.

 

 

Warrington formation : In this design, a layer of pairs of wires (one large and one small) is laid over an inner layer of wires. The number of wires in the inner layer is half of those in the outer layer. By its formation the strand is more circular (round). It provides a more wearing surface without losing its flexibility.

 

Combination formation : In many compound constructions, when there are more than two layers of wire over the centre wire, a combination of any two from among Filler, Seale and Warrington is designed.

Example : In the Warrington Seale construction, the intermediate layer has a Warrington relationship with the inner layer and a Seal relationship with the outer.