From the perspective of textile processing technology, the longer the fiber length, the better the processing performance, and the relationship between fiber length and yarn quality is also very close.
Under the same conditions, the longer the fiber and the better the length uniformity, the higher the yarn strength. This is because in the process of stretching the yarn to breakage, the cohesion between the fibers in the yarn increases with the increase of the fiber length, and the slippage rate between the fibers decreases relatively. At this time, the yarn The main factor for thread breakage is fiber breakage, by slippage, which can increase the strength of the yarn and reduce the end-break rate correspondingly during spinning. 
Under the premise of guaranteeing a certain strength of the yarn, if the fiber length is long and the uniformity is good, the spinnability is higher, the spun yarn is more even, the surface of the yarn is smooth, and the hairiness is less; the fiber length is short, especially the length uniformity When it is very bad, the short fibers are not controlled in the drafting area, and they are easy to become floating fibers, which are easy to form defects such as thick details and belly yarns, resulting in deterioration of yarn dryness and deterioration of yarn quality. In addition to being related to spinning quality, fiber length is also one of the basis for adjusting or designing the process parameters of each spinning system. When determining the structural size of each spinning equipment and the process parameters of each processing procedure (such as gauge, twist coefficient ), it must be ensured that it matches the length of the raw material used. For example, on the machines in each spinning process, the roller gauge increases with the length of the processed fibers; as the requirements for yarn strength are the same, when spinning with long fibers, a lower twist coefficient can be used, so that It can increase the output of the spinning frame, and at the same time, it can make the yarn with less twist, less hairiness and smooth yarn surface. The short-lint rate of raw materials is an important factor affecting the yarn evenness and finished rate. The higher the short-lint content in the raw material, the more yarn hairiness and the higher the pilling probability of the product; fibers with high short-lint rate The evenness of the spun yarn is also poor, so in order to increase the strength of the spun yarn and improve the evenness of the spun yarn, a large amount of short fibers must be removed through the combing process to improve the length uniformity of the raw material.