Maturity of raw cotton has an important influence on its linear density, strength, flexibility, cohesion and color characteristics. For fibers with different maturity, the degree of difficulty in separating fibers from fibers, fibers from impurities, the degree of formation of neps, strands and other defects, and the degree of breakage of fibers are different, that is, the processing performance is different, so the processing technology required is also different.
Under normal circumstances, raw cotton with normal maturity has good processability and can be processed by normal processing technology. The raw cotton fibers with poor maturity have thin wall, low strength, easy breakage, less natural curvature, small cohesion, low yarn strength, poor elasticity and rigidity, and easy kink into neps in work, which increase yarn neps and other defects. At the same time, it is difficult to separate fibers and impurities, and impurities are fragile, which increases the difficulty of elimination and the impurities of yarn formation.
These defects of raw cotton with poor maturity determine that it can not withstand severe blow and repeated rubbing in spinning process. Therefore, in order to reduce fiber breakage, prevent impurity fragmentation and reduce defects, appropriate processing technology should be determined. In the process of opening and cleaning cotton, we should adopt the process of loosening more, beating less, beating lightly, feeding slowly, feeding thinly, reducing roll, reducing back flower and reducing friction. Therefore, we should give full play to the role of cotton box machinery and free striking machinery, reduce grip strikes, properly reduce the speed of beaters, increase the distance between beaters, reduce quantities, properly increase noil, and eliminate impurity defects. In carding process, the speed of taker-in roll should be reduced appropriately, the distance between taker-in roll and feeding board should be increased, the clothing and mechanical condition should be kept in good condition, the main spacing should be correct, the carding should be guaranteed to be good, and the function of removing impurity defects should be strengthened. For raw cotton with poor maturity and other properties, separate slicing process should be adopted when necessary.