What is the effect of twisting on the performance of textile yarn in the post-processing process

In the post-processing process of textile yarn, the twisting process plays a vital role and has a profound impact on the performance of yarn. Twisting is to combine multiple single yarns or strands by rotating and twisting, so as to generate friction and cohesion between fibers, significantly improving the key performance indicators of yarn strength, wear resistance, elasticity and glossiness.

Improvement of yarn strength by twisting
The twisting process can significantly enhance the tensile strength of yarn. When the yarn is stretched by external force, the friction and cohesion between fibers effectively resist the slippage and breakage of fibers, thereby improving the breaking strength of yarn. In addition, twisting also helps to uniformize the strength distribution of yarn in the length direction. With the increase of twist coefficient, the number of twists at weak loops increases, thereby improving the strength of these areas, and ultimately leading to an increase in the overall yarn strength. However, the increase in twist coefficient is not unlimited. Too high twist coefficient will cause the fiber to bear too much preload due to tilting and twisting, resulting in a decrease in axial force, which may cause a decrease in yarn strength. Therefore, a critical twist coefficient must be found to optimize the yarn strength.

Effect of twisting on yarn wear resistance
The wear resistance of yarn refers to its ability to resist fiber shedding, breakage and structural damage during repeated friction. By twisting, the friction between fibers can be enhanced, making them more closely arranged, thereby improving wear resistance. In addition, twisting causes the fibers on the surface of the yarn to tilt to a certain extent, forming a twist width, which increases the friction area when in contact with external objects, thereby further improving wear resistance. Therefore, in textiles with high requirements for wear resistance, such as denim and canvas, high-twist yarns are usually selected.

Effect of twisting on yarn elasticity
Elasticity is the ability of yarn to restore its original shape and size after being subjected to external forces. Twisting improves the elasticity of yarn by making the yarn structure more compact and reducing the slip between fibers. Within the general twist coefficient range, an increase in twist coefficient is usually accompanied by an increase in elasticity. However, an excessively high twist coefficient will cause excessive tilting of the fibers, reduce the compressibility of the yarn, and thus reduce the elasticity. Therefore, in textiles that pursue high elasticity, such as stretch fabrics and sportswear, the twist of the yarn needs to be reasonably controlled to achieve the best effect.

Effect of twisting on yarn gloss and feel
Gloss and feel are important indicators of the appearance and comfort of textiles. The twisting process causes the fibers on the surface of the yarn to tilt, forming a unique texture and gloss. At an appropriate twist, the fibers on the surface of the yarn are arranged neatly and show a good gloss; when the twist is too high, the fibers are tilted excessively, resulting in a rough surface and reduced gloss. At the same time, twisting also directly affects the feel of the yarn. At an appropriate twist, the yarn feels soft and smooth; while too high a twist will make the yarn feel hard and rough. Therefore, in the pursuit of textiles with high gloss and high-quality feel, such as silk and high-end knitwear, the twist of the yarn must be precisely controlled to ensure the overall quality of the product.