Wenxiang Ye

Embeddable and locatable spinning

A novel spinning method: embeddable and locatable spinning, is reported for the first time in this paper. Analysis of the key restrictions of the conventional and some novel ring-spinning were studied; evolvement and principles of embeddable and locatable spinning were then introduced. Analysis indicated that embeddable and locatable spinning could overcome the existing restrictions of ring spinning and improve the spinning performance of fiber strands as well as the quality of the resulting yarn. Super-fine and colorful figured yarns could be produced successfully, and most fibers shorter than can be spun in traditional spinning could be well embedded into a yarn by embeddable and locatable spinning method; even staple fibers of low qualities could be used to produce a fine yarn of high qualities in the novel spinning system. This novel spinning method shows huge application potentials in textile industry by improving the yarn quality, developing super-fine yarn, and increasing fiber utilization rate.A novel spinning method: embeddable and locatable spinning, is reported for the first time in this paper. Analysis of the key restrictions of the conventional and some novel ring-spinning were studied; evolvement and principles of embeddable and locatable spinning were then introduced. Analysis indicated that embeddable and locatable spinning could overcome the existing restrictions of ring spinning and improve the spinning performance of fiber strands as well as the quality of the resulting yarn. Super-fine and colorful figured yarns could be produced successfully, and most fibers shorter than can be spun in traditional spinning could be well embedded into a yarn by embeddable and locatable spinning method; even staple fibers of low qualities could be used to produce a fine yarn of high qualities in the novel spinning system. This novel spinning method shows huge application potentials in textile industry by improving the yarn quality, developing super-fine yarn, and increasing fiber utilization rate.

Experimental Investigation on the Effect of Singeing on Cotton Yarn Properties

In this study, combed ring spun and compact spun cotton yarns with different counts were selected from different textile mills to conduct singeing treatment. Yarn properties including hairiness, fineness, unevenness and tensile properties were tested after the treatment and the results were compared with those before treatment. Hairiness was greatly removed after singeing, especially for short hairs with length less than 3 mm. Compact ring spun cotton yarns showed higher tex values and lower weight loss than combed ring spun cotton yarns under the same counts. Coefficient of variation of yarns increased slightly after singeing treatment. The unevenness of yarn was divided into two parts: basic unevenness of yarn body and hairiness unevenness, to explain the worse yarn evenness after singeing treatment. In this way, the effect of singeing on yarn properties was investigated thoroughly so as to improve yarn quality with less hairiness and good evenness.

A study on the relationship between irregularity and hairiness of spun yarns

In this study, Photoshop software was used to do image analysis on the photos of spun yarns. The result showed that yarn could be divided into two parts: the surface hairs and the stem. Based on this finding, a mathematical model of yarn unevenness was built to analyze the relationship between yarn unevenness and surface hairiness. The relationships among the coefficients of mass variance of the yarn, the stem and the surface hairs, expressed as CVt, CVs and CVh, respectively, were investigated in detail. Results indicate that the CVs of an uneven yarn always coincides with the irregularity of the yarn hairiness. More specifically, the CVt of a yarn cannot be better than those of both yarn hairiness and stem (CVh and CVs), even if one of them is excessive. It is rare for CV t to be higher than CVs after removal of yarn hairs. In particular, it is irrational for the CVt value to be higher than both CV s and CVh, which prompts a rethinking of the exact distribution of yarn hairs on the yarn body.In this study, Photoshop software was used to do image analysis on the photos of spun yarns. The result showed that yarn could be divided into two parts: the surface hairs and the stem. Based on this finding, a mathematical model of yarn unevenness was built to analyze the relationship between yarn unevenness and surface hairiness. The relationships among the coefficients of mass variance of the yarn, the stem and the surface hairs, expressed as CVt, CVs and CVh, respectively, were investigated in detail. Results indicate that the CVs of an uneven yarn always coincides with the irregularity of the yarn hairiness. More specifically, the CVt of a yarn cannot be better than those of both yarn hairiness and stem (CVh and CVs), even if one of them is excessive. It is rare for CVt to be higher than CVs after removal of yarn hairs. In particular, it is irrational for the CVt value to be higher than both CVs and CVh, which prompts a rethinking of the exact distribution of yarn hairs on the yarn body.

Fiber trapping comparison of embeddable and locatable spinning with sirofil and siro core-spinning with flute pipe air suction

In this study, we compared fiber trapping of embeddable and locatable spinning (ELS) with that of sirofil and siro core-spinning with flute pipe air suction. Online pictorial analysis showed that the 3rd ELS was free of the visual fiber loss during the 1st ELS, 2nd ELS, sirofil, and siro core-spinning. This indicated the 3rd ELS possessed high ability of trapping staple fibers. Weight loss of different yarns proved that the 3rd ELS had a statistically higher fiber trapping capacity than 1st ELS, sirofil and siro core-spinning. Yarn visual appearance results showed that filaments failed to be entirely buried in the siro core-spun yarn body due to the staple fiber loss and imperfect filament tension adjustment. Poor trapping and filament fasting of staple fibers might be the reasons for more hairy siro core-spun yarn than other composite yarns. Sirofil and siro core-spun yarn had higher value of coefficient of mass variation per unit yarn length and yarn imperfections than the 3rd ELS yarn which might be probably due to their irregular fiber loss during the sirofil and siro core-spinning. The fiber loss would result in a decrease in yarn cross-section fiber utilization; therefore, sirofil, siro core-spun and the 1st ELS yarn had a statistically lower tensile tenacity than the 3rd ELS composite yarn.

A study of influence of the delivery rubber roller on yarn properties

In this study, a mechanical model was introduced to analyze the hair wrapping via a contact surface in the yarn formation zone. Worsted and ramie/cotton rovings were then used to produce yarns on an experimental ring frame with and without a delivery rubber roller to validate the theoretical analysis. Yarn properties, including hairiness, unevenness, and tensile properties were tested and the results indicated that the delivery roller could stop fibers from escaping from the twisting process in the spinning triangle and wrap most of them onto the stem of the yarn. In particular for worsted spinning, yarn unevenness CV, as well as tensile properties, was improved significantly due to an improved arrangement of the worsted strand when using the front delivery rubber roller. However, yarn evenness and tensile properties deteriorated for ramie/cotton yarn spun with a delivery rubber roller. This was mainly because of the high modulus of the ramie/cotton blend strand, as upstream twists were blocked and a weak spinning zone was formed to incur an unexpected drawing.In this study, a mechanical model was introduced to analyze the hair wrapping via a contact surface in the yarn formation zone. Worsted and ramie/cotton rovings were then used to produce yarns on an experimental ring frame with and without a delivery rubber roller to validate the theoretical analysis. Yarn properties, including hairiness, unevenness, and tensile properties were tested and the results indicated that the delivery roller could stop fibers from escaping from the twisting process in the spinning triangle and wrap most of them onto the stem of the yarn. In particular for worsted spinning, yarn unevenness CV, as well as tensile properties, was improved significantly due to an improved arrangement of the worsted strand when using the front delivery rubber roller. However, yarn evenness and tensile properties deteriorated for ramie/cotton yarn spun with a delivery rubber roller. This was mainly because of the high modulus of the ramie/cotton blend strand, as upstream twists were blocked and a weak spinning zone was formed to incur an unexpected drawing.

Comparative study of cotton, ramie and wool fiber bundles’ thermal and dynamic mechanical thermal properties

Wool, cotton and ramie thermal properties are qualitatively studied by temperature-dependent Fourier transform infrared (TD-FTIR) spectroscopy, and quantitatively investigated by thermogravimetry coupled with a differential thermal analyzer (TG-DSC). TD-FTIR results indicate that although cotton, ramie and wool exhibit significant water loss, they have no detected degradation within the temperature range from 25℃ to 210℃. These data are confirmed by TG-DSC analysis. Dynamic mechanical thermal analysis provides comparative study of cotton, ramie and wool bundles’ dynamic mechanical thermal properties. The four-fiber-bundle has a much lower storage modulus due to its larger fiber contact surface and twisting deformation; heating reduces the storage modulus significantly for cotton and ramie instead of wool fiber bundles in the temperature range from 25℃ to 100℃. Key E′-T and tan δ-T curve information reveals that ramie fiber bundles have the strongest temperature sensitivity, while wool fiber bundles express the weakest temperature sensitivity.

Comparative study of fiber trapping by filaments in conventional and diagonal sirofil systems

In this study, geometrical and theoretical analyses were conducted comparatively for fiber trappings by filaments in the left diagonal, conventional and right diagonal sirofil with right strand and left filament arrangement (denoted as LDS-RS-LF, CS-RS-LF and RDS-RS-LF, respectively)and left diagonal, conventional and right diagonal sirofil with right filament and left strand arrangement (LDS-RF-LS, CS-RF-LS and RDS-RF-LS, respectively). White filaments and blue rovings were used to produce conventional and diagonal sirofil yarns to validate the analysis. Online and offline fiber trapping capacity comparisons indicated that CS-RS-LF and CS-RF-LS had higher capacities of trapping fibers than LDS-RS-LF and RDS-RF-LS, respectively, and lower capacities than RDS-RS-LF and LDS-RF-LS, respectively. Yarn appearance and tensile properties results revealed that diagonal sirofils with improved fiber trappings increased yarn hairiness and tensile properties, while the ones with deteriorated fiber trappings decreased yarn hairiness and tensile properties. Sirofil yarn unevenness CVm decreased as the fiber trapping enhanced by RDS-RS-LF and LDS-RF-LS and increased as the fiber trapping weakened by LDS-RS -LF and RDS-RF-LS. This corresponded well to our theoretical hypotheses on fiber trappings by filaments in conventional and diagonal sirofil systems.

A comparative study of hair trapping by a short grooved surface during conventional and siro-spinning

In this study, theoretical analysis was conducted for hair trapping by a short grooved surface contacting in different distances during conventional and siro-spinning, respectively. Then, blended cotton/ramie conventional and siro yarns were produced without and with the short grooved surface at different position distances. Hairs longer than 3 mm decreased as the surface position distance increased for both conventional and siro spun yarns, reducing short hairs by binding them onto the yarn stem. Conventional yarn hairiness H values decreased gradually as the surface position distance increased; however, siro spun yarn hairiness H values were similar without a gradual decrease as the surface position distance increased. The hair wrapping caused reduction of thin places, and occasional increase of thick places and neps for both conventional and siro yarns spun with the surface, respectively. Unevenness CVm results showed no serious deterioration after applying the surface during conventional and siro-spinning, and even some improved. The experimental results corresponded well to our theoretical analysis.

A study on the impact of hair wrappings on yarn properties – Part I: Theoretical analysis and manual experimental validations

Hair-wrapping distribution, hair-wrapping direction and yarn moving direction models have been developed to analyze and predict the impact of hair wrappings on yarn properties in theory. Then, Nm 48 ring-spun ramie yarns were respectively treated by various manual hair wrappings, such as the forward diagonal, the forward vertical, the forward random, the backward diagonal, the backward vertical and the backward random. The results showed that the various hair-wrapped yarns had a similar smoothened static surface appearance. Although vertical hair wrappings caused the highest deterioration in yarn unevenness and imperfections, they kept the smallest change of hairiness among all types of hair wrappings during yarn moving. Hair wrapping contributed to large fiber utilization, improving yarn tensile properties, regardless of the worsened yarn unevenness and imperfections. The manual experimental results corresponded well to our modeling suppositions and theoretical analysis.