The post-processing procedures of cotton spinning by twister include winding, doubling, twisting, singeing, spinning and baling, etc. The spinning yarn made of raw cotton and various chemical fibers through multiple processes is also required to go through post-processing procedures to meet the requirements of different varieties of yarns.
1. Improve the appearance and quality of products
There are still certain defects, impurities and coarse details in different types of tube yarns spun by spinning frame, which can be removed in the post-processing procedure. In order to make the strand smooth and round, some twisters equipped with a sink can also be wet twisting processing. Some of the high - grade strand also passes through the singeing to remove the surface hairiness, improves the yarn luster. The products requiring smooth yarn can be waxed.
2. Improve the internal performance of the product
Strand machining can change the yarn structure and thus its intrinsic properties. Different single yarns can be twisted once or twice, and different production processes can be used to improve the physical properties of the yarn, such as strength, wear resistance, dry, gloss, feel, etc. Fancy twisting can also change the structure and form of the yarn to form rings, rings, knots, points, joints and special yarns of different colors and thicknesses.
3. Stabilize the product structure
After different processing procedures, the stable yarn can be turned back and the single yarn tension in the uniform strand can be achieved. If the yarn twist back unstable, easy to cause "kink", "pigtail", "weft shrinkage" defects. Yarns with high or high twist stability are sometimes subjected to hot and humid setting. For example, the unevenness of the tension of each single yarn in the strand will lead to the "core-wrapped" structure of the strand, resulting in the decline of the strength, elasticity and elongation of the strand.
4. Make it into an appropriate roll
In order to meet the needs of the later process, the yarn should be made into different winding forms. The form of winding must meet the requirements of large volume, easy to unwind at high speed, and suitable for subsequent processing, easy to store and transport.