Improve the skewing phenomenon of the sweat wire coil in the large circular machine production

During the production of knitted sweat fabric (weft flat stitch structure) by the circular knitting machine, the distortion of the clothing is often caused by the skew of the coil, which seriously affects the appearance and quality of the product. How can the operating staff improve the distortion (skewing) of the sweat cloth? Cause analysis: 1. Twist of raw materials - The yarns currently used in knitting, especially cotton fibers, are twisted and combined into yarns. Once the loops in the fabric are formed, the yarns try to untwist, causing the loops to deform and become crooked (twisted). Additionally, in China, most cotton yarns are Z-twist, so the loops slope to the upper right in the longitudinal direction. 2: Unfilled coefficient of fabric - The larger the unfilled coefficient, the smaller the fabric density and the more obvious the twisting. The smaller the unfilled coefficient is, the more yarn contact points there are between the coils per unit area, which increases the frictional resistance and reduces the skew phenomenon. 3: The rotation direction of the circular knitting machine - When the circular knitting machine rotates counterclockwise, the degree of coil skew of the sweat fabric woven from Z-twist yarn will be reduced. Two: Improvement methods: 1. Steam the cotton yarn used - Through the moist heat effect of steaming, the twist activity of the cotton yarn is reduced and the twist force is decreased. After testing, it was found that if cotton yarn is steamed in a normal pressure steam yarn box for one hour before use, the skew of the loops in the sweat cloth can be improved by about 20%. 2: Use low-twist cotton yarn - Currently, most of the cotton yarn used in knitting is weft yarn for weaving, which has a relatively high twist. If special-spun yarn for knitting is used, the degree of coil skew in the sweat fabric can be improved. 3: Control the underfilling coefficient of the sweat cloth well - it is usually better to keep the underfilling coefficient within 16. 4: Using one Z-twist yarn and one S-twist yarn - This is a method currently adopted by many enterprises. By weaving with one Z-twist yarn and one S-twist yarn at intervals, the skew of the loops in the sweat fabric as a whole is basically non-existent. Weaving is carried out between Z-twist yarn and S-twist yarn. Due to the relatively low twist, the skew of the loops in the sweat fabric can be eliminated. 5: The twisting direction of the cotton yarn and the rotation direction of the single-sided circular knitting machine should be properly coordinated. In conclusion, by adopting the above several methods, the skew of the coils in the sweat cloth can basically be eliminated