Technical monographs Research and practice of compact spinning production process Liu Biying (Jiangsu Yueda Textile Group Co., Ltd.) conducted a process test study and compared the quality of multiple varieties of compact spinning with ordinary ring spinning yarns. : Compact spinning has obvious technical and quality advantages over ring spinning, through the correct selection of raw materials, control of the content of combed strips, reasonable selection of roving quantitative and enthalpy coefficient, preferred mesh circle number, bead feeding position and The process parameters such as the gauze roller gauge, the jaw size and the roving twist coefficient can stabilize and improve the compact spinning quality. According to the development needs of the market, our company is equipped with the German Suessen Ete compact spinning device on the DM129 spinning frame, which mainly produces combed compact spinning yarns below 145ex. Through the research and practice of technology in recent years, we have accumulated a certain experience in compact spinning production, the quality of our products has been steadily improved, and all kinds of varieties produced have been recognized by the market. Now we analyze some technical problems explored in the process of compact spinning production. Explore. 1 The effect of raw material properties on compact spinning quality is C11.7ex. For example, the comparison of the spinning quality of three different cotton blending schemes is shown in Table 1. Table 3 The spinning quality of the cotton blending scheme is compared with the upper half of the matching cotton spinning yarn. Average short cashmere rate dry kilometers detail kilometers thick section kilometers cotton knot hairiness ~ 3mm hairiness strong strong program coefficient coefficient length length / mm / root. Note: Raw cotton performance is HV1 test data. It can be seen from the test data that the cotton blending scheme 1 has a higher consistency coefficient of spinning, superior micronaire value, longer length, spun yarn), female, senior engineer, Yancheng, 224055: 2008-12-12 CV kilometer details, thick knots and neps are less, the strength is higher, but the yarn hairiness is poor. From the comparison of the three schemes, the H value of the yarn hairiness and the number of 3mm hairiness decreased with the decrease of the cotton linters. Therefore, it is advantageous to improve the quality of the compact yarn by selecting a cotton with a higher consistency coefficient of spinning, a better micronaire value, a longer length, and a lower lint rate. In actual production, we can focus on the selection of cotton indicators according to user quality requirements. 2The effect of the quality of semi-finished products on the quality of compacted yarns 21 The effect of the short-field content of the combed strips on the quality of the yarns The consistency of the short-staple content in the combed strips on the consistency of the fiber movement during the subsequent drawing, the compact spinning device The agglomeration effect of the strip has a certain influence. Table 2 shows the comparison of the quality of the cm.ea yarn in the case of different short velvet contents of the combed strip. It can be seen from Table 2 that with the addition of the linters in the combed strips, C11.7, the dry CV kilometers of the yarns have a tendency to increase; although the hairiness H value has no obvious difference, but the length The number of hairy roots in the segment, especially the number of 3 hairy feathers, has a tendency to increase with the length of the short pile in the combed strip; there is no significant difference between the average strength and the three conditions, but the minimum strength is increased with the rate of the short pile in the combed strip. And there is a significant decline. In the spinning process, in addition to the work of eliminating the short velvet in the combing process, it is necessary to strictly control the amount of short velvet in the process of cleaning and carding, and create better conditions for the combing to eliminate the linters, thereby reducing the production. The chance of a gauze point, reduced hairiness and weak ring. Table 2 The effect of the length of the combed strips on the quality of the finished yarns. The rate of the slivers of the combed strips/% of the dry squares. The details of the strips of kilometers per kilometer of cotton knots/3mm hairs/3mm hairs /N Note: The combet strip shorts ratio is the AFSS test index (less than 16mm). 22 Different roving quantification and twist coefficient For the production of C14.6e yarn for compact spinning quality, when different rovings are used to quantify and influence the roving twist coefficient, the yarn quality comparison is shown in Table 3 Table 3 Different roving quantitative and roving twist coefficient yarns Quality comparison test program roving quantitative / g (10m) 1 roving æ» coefficient strip dry kilometer detail / kilometer thick section / a kilometer cotton knot / hairiness 3mm hairiness strength can be seen from Table 3, when using larger When the roving is quantitative and the enthalpy coefficient, the dry CV value of the yarn is lower, but the yarn is thicker, the kilometer has more knots and the hairiness is more; when the lighter roving is used and the larger twist coefficient is used, the yarn is formed. The number of cotton knots and hairiness H are lower, and the number of 3mm hairiness is smaller. The addition of roving yarn has certain advantages for improving the level of the strip, and at the same time it can reduce the running cost of the enterprise. However, for compact spinning, the biggest advantage of yarn forming is that there is less hairiness, so it is better to use lighter roving and larger roving.æ» coefficient. 3The influence of the spinning process on the quality of the yarn 31 The influence of the mesh number on the yarn quality The Et compact spinning device is equipped with a closed lower apron (ie grid ring) with a curtain on the front roller output jaw. And a sizing roller having a diameter slightly larger than that of the front upper rubber roller to form an accumulation region of the fibers. The sizing roller is driven by the front squeezing roller through the gear. Since its diameter is slightly larger than that of the front upper rubber roller, there is a slight tension draft between the two, so that the stalks in between are always in tension. The grid loop is placed on a tubular straw (ie, a shaped tube), and the negative pressure in the shaped tube will be closely attached to the grid ring by the strip of the front roller jaw, due to the spinning Different numbers, the number of fibers in a single yarn is also different, and the required airflow adsorption force on the grid circle is also different. It is necessary to adjust the negative pressure and flow rate to achieve the best condensation effect. When the negative pressure of the system is constant, the mesh number of the grid circle is different, the flow rate is different, and the condensation effect must be different. C9.7, C14.6e different mesh circle number of yarn quality comparison see Table 4 from the comparison data can be seen, when the number of grid circles is larger, the yarn is dry, the kilometer thick section does not change much, but The kilometer detail, the hairiness H value and the 3mm hairiness number are all reduced. Therefore, the use of a larger number of mesh circles is beneficial to reduce yarn formation and improve hairiness. Table 4 Comparison of different grid circle mesh yarn quality Variety mesh density / mesh. M2 dry CV strip dry cv km detail / a kilometer thick section / a kilometer cotton knot / a hairy feather H 3mm hairy root. The effect of m 32 strip feeding on the suction groove position on the quality of the yarn. The shaped tube of the support grid ring has a narrow suction chute, the length of which is from the front roller jaw to the added grid circle and The clamping line of the rubberizing roller is stopped, so that the strips output from the front roller jaws are compressed, extending along the oblique path of the surface of the grid ring to reach the jaw line of the fiber gathering area, thereby realizing Table 5 The yarn quality is compared with the use of different strip feeding positions to eliminate the spinning and twisting triangle. The suction trough has a certain width, and the feeding position of the strip from the starting point of the suction trough is different, and the effect of the negative pressure airflow on the agglomeration of the whisker is different, and the yarn quality of the three varieties is different when the strip feeding position is used. For comparison, see Table 5. Variety of strips to be fed to the position of dry CV strips (V, kilometer detail / kilometer thick section / kilometer of cotton knot / hairiness H 3mm hairy root. m strip in the middle of the strip The edge strips are in the middle of the strips at the edge of the strips in the middle of the strips at the edges. It can be seen from the comparison of Table 5 that when different strip feeding positions are used, there are no significant differences in the conventional quality indicators, but the hairiness indicators are Larger difference. When the bead is fed at the edge, the hairiness H and the 3mm hairiness are reduced more. It can be seen that as the yarn number becomes thicker, the two feeding positions are compared, and the hairiness is reduced. A sharp drop, which should be related to the width of the feeding bar. Since the yarn number is coarse, the larger the roving is used, the width of the feeding bar is wider, and the width of the suction groove is limited, so the feeding is changed. In the position, the negative pressure in the suction groove is different from the set 6 of the whisker Output speed roller Comparative polyethylene yarn quality will not be great differences in effect. Roving actual production to combine quantitative, the number and quality cultivar, appropriate adjustment sliver feed position. 33 Different Roller Output Speeds on the Quality of Compact Spinning When changing the speed of the front roller, the time required for the strip to pass through the suction groove of the shaped tube is also changed. Theoretically, the negative pressure of the suction groove is concentrated on the whisker. The effect should also be different. When using different roller output speeds, the comparison of yarn quality of C9.7, C11.7 and C14.6 is shown in Table 6. Variety output speed strip dry CV km detail / kilometer thick section / One kilometer of cotton knots hairy hair H 3mm hairy roots. When the m 7ex yarn is used, as the output speed decreases, the yarn index is obviously improved regardless of the dry level, the number of kilometers, or the hairiness. When spinning 7ex yarn, the output speed is 13 quality. The indicators are worse than the quality indicators of the other two speeds. When the speed is 12, the yarns are close to each other. When the C14.6ex yarn is spun, when the output speed changes, the indicators do not change significantly. This shows that when the yarn number is fine, the yarn quality is sensitive to changes in output speed. Lower speeds should be used when spinning yarns below C11. 7e. Table 7C117ex〗 Factor 3 Horizontal Orthogonal Test Results 34 Effect of Different Process Combinations on Compact Spinning Quality To better select process parameters and achieve a superior process combination, we performed roving twist coefficient and spun yarn on C11.7tx varieties. 3 factors and 3 levels of orthogonal test of rear roller gauge and fine yarn jaw spacing. The test results are shown in Table 7. Test Roller Gauge Gauge Block Specifications roving sliver dry (V strip dry (V, km detail km thick section thousand M cotton knot hair feather H serial number coefficient / one pair of orthogonal test results using the range analysis method (calculated from abbreviated) with hairiness H as the main consideration index, the preferred process combination is: roller spacer 18nX35mm jaw spacing 30mm roving æ»When the coefficient 115 is based on the strip dry CV as the main consideration index, the preferred process combination is: roller spacer 18mmX33mm jaw spacing 275mm roving twist coefficient 123 due to the small difference between the hairiness index of each level of the roller gauge, the roving twist coefficient 115 The level and the difference between the level of 123 and the time is also small, so the hairiness H is the main, and the combination of the best dry CV process is: Roller gauge 18mm Table 8 compact spinning and ordinary ring spinning quality comparison 33mm jaw spacing 3 . 0mm roving twist factor 115 raw Should be based on actual demand, we have focused on the process design, to meet customer quality requirements. 4Comparative analysis of the quality of compact spinning and ordinary ring spinning For several years, our company has produced a variety of compact spinning yarn varieties, and the comparison of the quality of several representative varieties with ordinary ring spinning is shown in Table 8 Spinning strip dry [V strip dry CV km detail kilometers thick section km cotton knot hairiness 3mm hairiness strong strong CV type / a compact spinning ordinary ring spinning compact spinning ordinary ring spinning compact spinning ordinary ring spinning compact spinning ordinary Ring spinning can be clearly seen from Table 8. The advantages of compact spinning compared to ordinary ring spinning are mainly as follows: the reduction of 3mm hairiness in the 146蜉18.2ex4 varieties is 79. 18.2tx4 Among the varieties, the strong increase of compact spinning compared with ordinary ring spinning is 8. (3) The dry CV value is reduced, and the frequent defects are reduced. 7.3 Among the 18.2ex4 varieties, the stem CV decreased. 80.49, 0.4 and 0.4 percentage points; all kinds of frequent defects are also reduced to varying degrees. In addition, compact spinning can reduce the twist, which can improve the spinning speed and production efficiency, and the yarn forming style is softer. The negative pressure system in compact spinning can reduce the fly in the production workshop, which is conducive to clean production; compact spinning strength High and uniformity can reduce the break rate of the post-process and improve the labor production efficiency; the compact spinning hairiness is greatly reduced, the sizing rate can be reduced, the slurry consumption can be reduced; the singeing process in the printing and dyeing process can be eliminated, and energy is saved; In the printing and dyeing, the dye consumption can be reduced, the chromatic aberration can be reduced, and the color can be more uniform; the fabric woven with the compact spinning yarn is smooth, flat and the quality is improved. 5 Conclusion The compact spinning can greatly reduce the yarn hairiness, improve the stem and improve the strength, and has obvious technical and quality advantages compared with ordinary ring spinning. With the continuous improvement of compact spinning equipment and the maturity of technology, it will play an increasingly important role in the production of high-grade fine-grain high-density fabrics and occupy more market share. The production of high-quality compact spinning yarns not only requires the deployment of high-performance compact spinning units, but also relies on a solid equipment foundation, meticulous and standardized operation management, strict quality management and thoughtful scientific process management. In-depth and meticulous process test research should be carried out from raw material matching, semi-finished product quality and technology, compact spinning parts and spun yarn related process parameter configuration to find out the process optimization plan; at the same time, equipment maintenance and maintenance work must be strengthened to reduce the cost of key equipment. To solve the quality problems of intarsia, yarn-forming mechanical waves and quality differences between ingots in the grid circle, the performance of the compact spinning device can be fully utilized. Waffle Knitted Fabric,Dark Colour Fabric,Waffle Checks Fabric,Custom Waffle Knitted Fabric Shaoxing Weihui International Trade Co.,Ltd. , https://www.weihui-fabrics.com