Function of the core

Function of the core

The core is the foundation of wire rope. Its primary function is to support the wire strands of which the rope is composed, keeping them in their correct relative position during the operating life of the rope. As the wire is loaded, the strands imbed themselves more firmly into the core. The resulting axial movement increases the interstrand pressure where the strands contact each other. It is necessary that the core be strong enough to restrict the magnitude of the interstrand pressure. In most wire rope applications, the rope is in motion over sheaves and winding drums.


In most instances, an independent wire rope core is the answer to the problem of interstrand pressure. This core is a small wire rope itself and acts as support for the strands of the wire rope. This combination of a wire rope within a wire rope greatly improves the ability of the rope to operate with success under conditions where a fibre rope would fail. Another advantage of independent wire rope core is that of reduced stretch.

Other advantages are:

1. Reduced tendency for the rope to rotate.
2. Longer rope life when operating at high temperatures.
3. Tensile strength increases over that of fiber core rope . The ability of an independent wire rope core to support the strands of a rope often makes the difference between satisfactory and unsatisfactory rope service.


There are two main types of fiber core, one being synthetic the other natural. Sisal and Jute is the most commonly used natural fiber, but polypropylene and other synthetics are becoming more widely used each year.