The wear resistance and fatigue resistance of a wire rope are a pair of characteristics that affect each other, and the main influencing factor is the outer wire of Steel wire rope. For steel wire ropes of the same diameter, same strength, and same number of strands, the more the number of outer wires, the smaller the diameter of the outer wires, which means that Steel wire rope has poor wear resistance and better fatigue resistance and vice versa . Therefore, in the selection of Steel wire rope, the wear resistance and fatigue resistance of Steel wire rope should be comprehensively considered to meet the use requirements of Steel wire rope as much as possible.

The elongation of Steel wire rope: When Steel wire rope is subjected to a tensile load, it will stretch in different stages. Before Steel wire rope is used, pre-tensioning Steel wire rope is the only way to eliminate its structural elongation.
There are many factors that can cause Steel wire rope to elongate during use, and some factors cause the elongation to be negligible. The main reasons that usually lead to the elongation of Steel wire rope are as follows, of which the first two are the most important factors.
Structural elongation The elongation caused by the adjustment of the position of the steel wire in each strand and the strands in Steel wire rope; the elongation caused by the free rotation of one end of Steel wire rope and the increase of the lay length; the metal area of ​​Steel wire rope is reduced due to the wear of the internal wire The further elongation caused by small, the above-mentioned elongation is collectively referred to as structural elongation.
Elastic elongation The elongation in the elastic range of the material due to tensile load.
Plastic elongation The permanent inelastic elongation caused by the load exceeding the yield point of the material.
The elongation or shortening of temperature due to temperature changes.
The role of wire rope pre-tensioning:
1. When Steel wire rope is pre-tensioned, it can basically eliminate the elongation caused by the position adjustment of the steel wire in the strand and the position of each strand in Steel wire rope. The method is to apply a certain load and repeatedly stretch until the structural elongation of Steel wire rope is eliminated;
2. Elimination of twisting stress: the steel wire rope strands and the steel wires in the strands will have a certain residual stress after twisting. Through pre-tensioning, the twisting stress can be eliminated to a large extent;
3. Make the strands and steel wires evenly stressed: Due to the unevenness of the twisting, the strands or steel wires of the steel wire rope receive uneven forces when they are loaded. Pre-tensioning can make the force uniform;
4. Improve fatigue life: Due to the elimination of twisting stress and uniform force, the fatigue life of steel wire rope can be improved to a certain extent.
The above is the extensibility of Steel wire rope, I hope it will be helpful to everyone.