The causes and solutions for preventing hidden horizontal stripes in circular knitting machines

Obvious horizontal bars are easy to spot and fix, while hidden ones are more troublesome. Hidden horizontal stripes refer to the phenomenon where, during the operation of a circular knitting machine for one cycle, the size of the coils changes, resulting in sparse and uneven fabric surfaces. The causes of hidden horizontal stripes: Generally speaking, the possibility of hidden horizontal stripes occurring in raw materials used in circular knitting machines is relatively small. It is mostly due to mechanical wear and failure to adjust in time, resulting in periodic uneven tension and the appearance of hidden horizontal stripes on the fabric surface. (1) Due to the low installation accuracy of the circular machine or severe wear caused by its aging; The levelness, concentricity and roundness of the syringe (needle disc) of the circular knitting machine exceed the allowable tolerance range. (2) During the operation of the circular knitting machine, debris such as flying flowers gets embedded in the slider inside the yarn feeding disc, causing abnormalities in the synchronous belt (or perforated belt), resulting in unstable yarn feeding and the appearance of hidden horizontal stripes on the fabric surface. (3) Sometimes, in order to weave and produce special varieties, the yarn feeding needs to be done in a passive way. This results in a significant difference in the tension of the yarn during the feeding process, causing hidden horizontal stripes to appear on the fabric surface. (4) During the winding process of the drawing and winding device of the circular machine, due to significant wear, the tension fluctuates greatly, resulting in differences in the length of the coils. 2. Prevention and solution methods: (1) Electroplate the positioning surface of the gear disc and appropriately thicken it to control the wobble of the gear disc within 0.1mm to 0.2mm. (2) Polish and grind the bottom steel ball track, apply grease, level the bottom of the syringe with a soft and thin elastic pad, and control the radial shaking of the syringe at about 0.2mm. (3) The triangle of the settling plate (sinker plate) needs to be calibrated regularly to ensure that the distance between the triangle of the settling plate and the tail of the settling plate is controlled between 0.3mm and 0.5mm, and to ensure that the tension of the holding yarn is consistent when the settling plate is unwound. (4) Control the temperature and humidity in the workshop to prevent debris such as flying flowers and dust from adhering to the winding machine parts due to static electricity, which may cause unstable yarn feeding tension. The most important thing is to do a good job in the cleaning and hygiene of the circular machine. (5) Others: Inspect and maintain the traction and coiling device properly to ensure a constant traction tension. Use a tension meter to test the yarn feed tension to ensure that the yarn feed tension is approximately the same. In conclusion, during the weaving production process of the circular knitting machine, due to the different structures of the coils, the degree of hidden horizontal stripes also varies. Generally, the single-sided circular knitting machine is more obvious than the double-sided circular knitting machine. Therefore, we need to enhance the daily maintenance and repair work to keep the circular knitting machine in the best condition, so as to ensure the production of high-quality fabrics.