1. Impurity removal
Yarn is generally made of many short fibers of different lengths by splicing, and also by twisting long continuous monofilaments. In the spinning process, it is first necessary to remove miscellaneous defects, that is, preliminary processing of raw materials. The types of raw materials are different. The preliminary processing methods of raw materials mainly include physical methods, chemical methods and the combination of physical and chemical methods.
2. Release
To process the disordered and closely connected fibers into smooth yarns with certain requirements, it is necessary to change the block fibers into a single fiber state, remove the horizontal connection of fiber raw materials, and establish a solid vertical connection between the head and tail. The loosening of fiber is to completely remove the transverse connection between fiber and fiber, but the damage of fiber must be reduced as much as possible.
3. Open loose
Loosening is tearing a large piece of fiber into small pieces and small fiber bundles. In a broad sense, degumming of hemp is also a kind of loosening. With the opening action, the contact force between the fiber and the impurities is weakened, so that the impurities are removed and the fibers are mixed.
4. Comb
The carding function is that a large number of dense carding needles on the carding machine further loosen the small pieces and bundles of fibers into a single state, so as to further improve the loosening of fibers. After carding, the transverse connection between fibers is basically relieved, and the impurity removal and mixing function is more sufficient. However, a large number of fibers are curved and have hooks, and there is still a certain horizontal connection between each fiber.
5. Combing
The combing function of the comber is to use the comb to conduct more detailed combing under the condition of holding the two ends of the fiber respectively. Combing machine processing can eliminate short fibers and small miscellaneous defects below a certain length, and promote fibers to be more parallel and straight. Chemical fiber is generally not processed by combing machine because of its neat length, less impurities and good straightening and parallel state.
6. Draft
The carding strip is elongated and thinned to gradually reach the predetermined thickness. This process is called drafting. It lays a foundation for firmly establishing a regular head to tail connection between fibers.
7. Twisting
Twisting is to twist the whisker around its own axis to make the fibers parallel to the axial direction of the whisker spiral, so as to generate radial pressure to fix the longitudinal connection between the fibers.
8. Winding
Winding semi-finished products or finished products into a certain form to facilitate storage, transportation and processing of the next process.
