Influence of the hottest winding process on Yarn H

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The influence of winding forming process on yarn hairiness

this paper analyzes the influence of spinning winding forming process on yarn hairiness, reveals the characteristics and rules of hairiness change in spinning forming process by using two common hairiness detection methods, and gives some suggestions to improve hairiness index

for the detection of yarn hairiness, there are several different methods in the world, among which the more representative ones are the Swiss Uster hairiness detection method, Zweigle detection method and Shirley method

spectrogram of the change of Uster hairiness index

these detection methods have different characteristics. The USTER method can test the total length of hairiness per centimeter of yarn at high speed, and give the distribution characteristics of hairiness, hairiness deviation (SH) in the tube and the change trend of hairiness in the whole test length (curve diagram, spectrum diagram); Zweig method (domestic similar equipment is ygl71b feather meter) can divide the hairiness on the unit length of yarn into 12 different length grades, and calculate their number and distribution respectively

these two methods reflect the characteristics of hairiness change and distribution from different angles ● standard punch ball: φ 20 ± 0.05mm, and then analyze the cause of hairiness and predict the impact of hairiness on the finished product

influence of spinning frame winding forming

in the spinning process, the tension change of yarn in the process of yarn winding is more complex, which is also a main factor to produce yarn surface hairiness. In the detection of feathering, just like the evenness meter, the feathering meter can also give a curve and spectrum that reflect the change of feathering

from the hairiness index change curve and spectrum, we can see that there is a strong periodic hairiness index change at about 5.75 meters. This is because in the ring spinning process, due to the differences in process and equipment conditions (ring, ring model, winding process), the winding tension (or balloon) of the yarn changes differently in the winding process, which leads to the balloon is too large, so that the balloon collides with the yarn separator, and finally leads to the hairiness index is too large

in actual production, during the winding process of tube yarn, because the balloon width of yarn is greater than the spacing of yarn separator, the collision and friction between yarn and yarn separator will produce periodic hairiness changes. With the movement of the ring plate in the winding process, the yarn winding tension changes, and then the hairiness index also changes

The shape and size of the balloon reflect the force between the yarn and the bead: the lighter the bead, the smaller the tension, and the larger the balloon. On the contrary, the heavier the coil, the greater the tension, and the smaller the balloon

the weight of the steel ring is light. During the winding process of the tube yarn, when the tube yarn is at the pin, the width of the balloon is greater than the spacing between the yarn separator plates. At this time, there is collision and friction between the yarn and the yarn separator plates, causing damage to the surface of the yarn and excessive hairiness

however, with the change of winding range, the shape of balloon also changes. That is, the closer the tube yarn winding is to the export to developed countries, and the middle and low ends are the top of the main yarn, the smaller the shape of the balloon and the narrower the width of the balloon; When the balloon width is less than the spacing between the yarn separator plates, the yarn and the yarn separator plates do not rub, so it is not easy to produce hairiness caused by collision with the yarn separator plates

production example

in actual production, we can judge whether the hairiness characteristics form Periodic hairiness index variation by visually observing the shape of the winding balloon and the position with the spacer plate. In this test, observe several spindles on the spinning frame, remove them, and test the hairiness index on the USTER tester 3 first, and then on the yg172 yarn hairiness detector

from the hairiness index change curve, it is observed that the impact of tube yarn 1 is serious, and its periodic variation is the heaviest as reflected by the hairiness index change curve; The impact of tube yarn 2 is lighter than that of tube yarn 1, and the degree of periodic variation is lighter than that of tube yarn 1; The balloon of tube yarn 3 does not collide with the spacer plate, and there is no periodic variation observed from the hairiness index change curve

the hairiness test result of Uster tester 3

tube yarn 4~10 is the subsequent random observation and sampling. There is no collision between the balloon of tube yarn 4 and 7~10 and the yarn separator. Like tube yarn 3, there is no obvious periodic hairiness index variation on the change curve; Tube yarns 5 and 6 are observed to have air loops colliding with the yarn separator, and strong periodic variation is also observed in the hairiness index change curve. The mean square deviation of hairiness index of tube yarn 1, 2, 5 and 6 is significantly higher than that of other tube yarns

based on the test results of the above 10 tube yarns, small differences that cannot be reflected in the hairiness index change curve can be further observed on the spectrogram: no periodic hairiness index variation is observed on the hairiness index change curve of tube yarns 3, 4, 8 and 9, but the existence of periodic variation of hairiness index with weak intensity is observed on the spectrogram corresponding to the continuous "graphene +" action

different from the variation coefficient of evenness CVM%, hairiness index reflects the surface structure of yarn, and the change of hairiness index of yarn of the same variety can directly reflect the inter tube difference of hairiness index in this variety

corresponding to urst hairiness index, the test results of yg172 hairiness tester have a good correlation with it. If the USTER hairiness index of tube yarn 1 is high, the number of hairiness at 1mm, 2mm, 3mm and other levels measured by the corresponding yg172 hairiness instrument also increases, that is, with the increase of Uster hairiness index, yg172 hairiness value also increases by varying degrees

conclusion and suggestions

in the whole winding process, the yarn tension at the bottom of the tube yarn is small, and the shape, size and width of the balloon are larger than the size when the tube yarn is wound to the top of the tube yarn. Therefore, in the whole winding process, the hairiness index changes from large to small from the bottom of the tube yarn to the top of the tube yarn

in the lifting process of a ring plate, the shape of the balloon when the ring plate runs to the bottom (binding layer) is larger than that when it runs to the top (winding layer). In this process, the bottom hairiness index is greater than the top hairiness index

comparing the tube yarns with two different spindle positions, it can be seen that the tube yarn with larger balloon shape (greater damage to the yarn surface) forms more hairiness

measures to reduce the variation of hairiness index and the difference of hairiness index between tubes:

strengthen the management of wire rings: in the production process, strictly enforce the use of wire rings to ensure that the model of wire rings used by each kind of yarn is unique

strengthen process optimization: according to the characteristics of different yarn varieties, select different types of steel rings and steel rings to reduce the hairiness index to the lowest value

transform or update the equipment: for example, use large-diameter steel collars to reduce the hairiness increase of low count yarn due to the relatively light use of steel rims (which can not make and greatly reduce the corresponding steel rims used in the system control circuit) and the large air rims, which cause the yarn to collide with the yarn separator. If the steel ring is too heavy, it will lead to the increase of broken ends

strengthen the maintenance of equipment and machine: adjust and repair the skew yarn separator in time, replace the yarn separator with rough surface in time, and use metal yarn separator to reduce the impact of yarn surface damage due to the rough surface of the yarn separator; Timely adjust and repair the eccentric spindle, eccentric yarn guide hook and other winding parts that affect hairiness

due to the periodic variation of hairiness, when using ygl71b hairiness instrument (and similar equipment) to test yarn hairiness, the winding length of the spinning frame should be considered in determining the test length - that is, the test length should be greater than the forming winding length of the spinning frame of the yarn sample to be tested

originally published in China Textile and clothing (end)

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