reason why the steel wire rope has an extremely important position in the hoisting operation, in addition to the excellent characteristics of its own material, is also inseparable from the entire rigorous manufacturing process and quality inspection. We popularize the twisting process of steel wire rope, through the twisting of multiple steel wires, a large strand of strong steel wire rope is formed, but some people are puzzled about this, why the steel wire rope will not loosen after twisting?

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　　Steel wires usually have elastic recovery properties. According to most people's thinking, two steel wires will loosen under the elastic recovery effect after they are twisted together. However, the steel wire rope will not, not only It will not loosen, and it is still immobile and very compact. In response to this phenomenon, Chenghua Manufacturing will show you about the non-loose processing of steel wire ropes.

　　Due to the presence of twisting stress and unilateral counter-moment in the wire rope, the strands or ropes are loosened in the opposite direction of the twisting direction, which affects the performance of the wire rope. To this end, various manufacturers have taken some effective technological measures. For example, pre-deformation and post-deformation of strands, post-deformation and sizing of ropes, pre-stretching of wire ropes before leaving the factory, etc.

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　　①Pre-deformation: Before closing the rope, the strands (such as triangular strands) are repeatedly bent and deformed by the pressure roller in the pre-deformation device. So as to eliminate the twisting stress of the steel wire and obtain a technological measure that is not loose.

　　②Post-deformation: The twisted strands or wire ropes will be taken out from the pressing shoe, and further bent and deformed by the pressing roller of the post-deformer to relieve stress. In this way, better non-loose properties can be obtained, and the tightness and surface quality of the wire rope are also increased.

　　③ Pre-stretching: Before the wire rope is put into use, it is a stretching process in which the load is repeatedly applied by the pre-stretching device, so that the structure of the wire rope tends to be stable. This can reduce the residual elongation of the wire rope due to structural elongation during use.

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　　Pre-stretching implementation method: first apply a load equal to 50% of the breaking force of the rope, maintain 5m, unload to 5% of the breaking force, repeat twice and then relax. After the non-loose process measures, the structure of the wire rope is made more compact, and the wire or strand will not be loose after the rope head is cut off, which greatly improves the bending fatigue strength of the wire rope.

　　It is through this process that the wire rope becomes less loose and more compact. This treatment also makes the wire rope extremely powerful in lifting operations.