Optimization Of Carding Equipment Performance To Improve Yarn Quality

With the development of cotton spinning industry and the progress of science and technology, various differential spinning fibers have been developed, and various new cotton yarn products have been developed one after another. It has been proved by practice that the carding process, as the heart of spinning, is particularly important in improving the quality of differential fiber yarns. Especially, the selection and matching use of special carding equipment for each part of the carding machine table are highly valued by the industry. Through several years of exploration and practice, our company has summarized a set of production experience from the selection of carding equipment, process configuration and impact on product quality in the development of products focusing on differential fibers.

Practice has proved that due to the great difference in the basic properties of various differential fiber materials, the first thing to consider on the carding machine is whether it can be produced normally, and there should be no winding cylinder, doffer transfer difficulties, cotton web falling, or poor web quality, or difficulties in slinging. Therefore, the selection of carding equipment should consider both the quality and the applicability of various fibers to ensure normal production. Through long-term tests, our company's carding equipment is mainly selected from the card clothing manufacturers such as Nantong Jinlun, Graff, Switzerland, and Kanai, Japan; There are also some mature experiences in the selection of equipment specifications.

　　 Cylinder card clothing It is the key to all the equipment of the entire carding machine and is responsible for the main function of carding. Therefore, special attention should be paid to the selection of cylinder card clothing, including the material, specification and model of cylinder card clothing, card clothing treatment process, etc., which should not only meet the development requirements of high-speed and high-yield carding machines, but also meet the production requirements of diversified varieties.

In terms of card clothing specifications, although we produce differentiated fibers, we insist on cotton card clothing technology The characteristics shall meet the basic requirements of "short, shallow, sharp, thin, dense and small", generally 20 series, the tooth density shall be controlled at no less than 800 teeth/square inch, the tooth base thickness shall be 0.4~0.5 mm, and the working angle shall be generally controlled at 60 degrees. At the same time, the transverse tooth density shall be adopted to fully comb and mix the fibers, minimize the bundle fibers, and improve the fibre The single fiber state of. In this case, the yarn indexes are relatively good, especially the neps and yarn defects. Table 1 shows the comparative test data when using different specifications of cylinder card clothing.

The selection of the flat card clothing should be matched with the cylinder card clothing. The hardness and wear resistance of the needle tip of the flat card clothing should be guaranteed, and the bending resistance of the comb needle should be guaranteed to avoid damage to the card clothing caused by the straightening of the card clothing during the carding process. The planting needles are arranged in a sparse and dense manner, and the density is generally the denser type, with the density of 340~420 needles/square inch. Table 2 is a comparative test of our company in selecting different specifications of flat card clothing. From the test results, it can be seen that properly increasing the density of the flat plate will improve the yarn quality to a certain extent.

Generally, the doffer clothing adopts a small process angle to facilitate the transfer and stripping of fibers. A relatively high circular tooth shape is selected in the height of the needle teeth to increase the capacity of fibers between teeth and the holding force of fibers, thus improving the transfer of fibers, and at the same time guiding the airflow generated by the high-speed rotation of the cylinder. For the differential fibers with poor relative cohesion between fibers, in order to effectively improve the transfer of fibers, the currently launched doffer card clothing with grooves on the side is being gradually used. For this card clothing, our company has also conducted relevant experiments (see Table 3). With grooved card clothing, its yarn forming index is obviously improved, especially+200% neps and a1 defects. The practice shows that this kind of card clothing has obvious effect on the cohesive fiber, and the original phenomenon of web dropping in the doffer triangle area can be well solved, thus reducing the generation of card sliver unevenness, thick and thin knots and other defects.