The wire rope is a rope more or less flexible, constituted by a set of metal wires, tightly wrapped in the shape of a helix.
The structure of steel ropes is variable according to the specific needs due to the end use.
For simplicity it is possible to divide the rope into two distinct families: core / fiber and textile and steel core.
The ropes are generally circular cross-section;
A steel rope is formed by a number of steel wires normally rolled into strands, in turn coiled around a central core in turn constituted in turn by a strand or by a real rope d ‘ steel with a smaller diameter, or a core textile, currently commonly polypropylene.
The metal core increases about 8% the breaking load of the rope to the core fiber textile, but reduces its flexibility. The fiber core textile also has the important function of reservoir for the lubricant.
The types of steel used vary according to the use, from carbon steel with a tensile strength of 1370 N/mm2, up to the harder steels for ropes intended for use with heavy lifting resistance of the wires up to 2160 N / mm2.
There are also cables of stainless steel, having strength 1470-1570 N/mm2, for particular applications (marine, chemical industry, food industry, and military applications where it is required a high resistance to chemical and atmospheric agents or magnetic permeability).