After open-and-clear cotton machine processing, the fibers in cotton rolls or loose cotton are mostly loose cotton blocks and bundles, and contain 40%~50% impurities, most of which are fine and strong adhesiveness fibers (such as broken seeds with fibers, seed crumbs, soft seed epidermis, neps, etc.). Therefore, it is necessary to thoroughly decompose the fiber bundle into a single fiber, remove the minor impurities remaining in it, make the cotton blending component fibers fully mixed in the single fiber state, and make a uniform sliver to meet the requirements of the later process.
Carding is the use of flat or roller carding machine, with the help of needle surface movement, small cotton bundles combed into a single fiber state, further remove impurities and non-spinnable staple fibers, so that the fibers parallel stretch, and finally made into cotton sliver into the barrel.
Tasks of carding process:
- On the premise of minimizing damage to fibers, combing the feeding layer carefully and thoroughly, so that bundle fibers can be separated into single fibers.
- Removing impurities thoroughly removes residual impurity defects on the basis of full separation of fibers.
- Uniform blending makes the fibers fully blend and distribute evenly in the single fiber state.
- To make uniform slivers of certain specifications and quality requirements and place them regularly in sliver barrels.
The task of carding process is accomplished by carding machine. The degree of separation of cotton bundles into single fibers on carding machine is closely related to yarn strength and evenness. The effect of removing impurities determines neps and evenness of yarn to a great extent. The noil rate of carding machine is the most in the single machine of general carding system, and there is a certain amount of spinnable fibers in noil, so the quantity and quality of noil of carding machine are directly related to the amount of cotton used.