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The strand is the simplest construction: It consists of one or more layers of superimposed wires laid spirally around one or more central wires or around a fibre core. The construction of the strand is identified by the number of wires in the individual layers, starting from the outer one (e.g. 12+6+1 or 15+9+FC). FC indicates a fibre core. Distinction is made between strands with cross laid and equal laid wires.

Strands With Cross Laid Wires

All the wires in this type of strand are of equal diameter and for geometrical reasons the number of wires decreases in each layer, starting from the outermost one, according to an arithmetical progression basedonnumber(18 + 12 + 6 + 1 or 12 + 6). In cross laid constructions each layer of wire is laid up a separate operation with a different length of lay. the result being the crossing of the various layers of wires. Consequently strong pressure occurs between the wires which may break, especially with variable loads.

Wire ropes are lubricated as a protection against oxidization and to reduce friction between wires and strands. Fiber cores are impregnated for preservation purposes. During the stranding and roping operations, all wires forming the strand and all strands forming the rope are lubricated. The type of lubrication varies according to the application for the rope and the type of plant for which it is intended. During the working life of the rope, lubrication should be carried out periodically with good quality products compatible with those used during manufacture and which we shall be pleased to indicate upon request.

Lubricants used during manufacture shall be free from solvents, moisture, aromatic compounds, alkaline soaps and acidity both organic and inorganic. For protection of wire ropes against corrosion and frictional wear, elephant wire ropes have various kinds of lubrications.

• Ordinary Lay ropes are less likely to kink and untwist, and their ordinary lay ropes are less subject to failure from crushing and distortion. Because the longer length of exposed outer wires presents greater wearing surface.

• Long's Lay ropes have increased resistance to abrasion.

• Greater care must be exercised when handling Lang's Lay ropes, as they are more likely to kink and untwist than Ordinary Lay ropes.

• Ordinary Lay ropes are generally used because of their greater stability; however Lang's Lay ropes are preferred for guided loads such as passenger and freight elevators because the wires have a longer contact with the sheave grooves and consequently less wear. Given equal construction and diameter, Lang's Lay ropes are more flexible than the Ordinary Lay type.

• The wire ropes we manufacture are performed according to special methods which give them stability and eliminate internal stresses.

The IWRC is a metallic rope having for example a construction designated by 7 x (6 +1) or 7 x 7. Should the strands also contain a fibre core then the rope will be known for example as 6x (12 + FC)+FC or 6x 12 + 7FC. Lastly if the rope is formed of two or more layers of strands superimposed around a FC, then it will be known as:
12 x (6 +1} + 6 x (6 +1) + FC or 18 x 7 + FC.

Type of Lay

As already stated, round stranded ropes have both the strands and the wires in the strands laid helically.

• The lay of the outer wires in the strands be in the same direction or in the opposite direction to that of the strands in the rope, the result will be respectively a Lang's Lay rope or an ordinary (regular) Lay rope, having a right hand lay or left hand lay according to the lay of the strands.

• Right hand and left hand lays are designated respectively Z and S.