Reducing Yarn Hairiness Research Articles

An eco-friendly droplet-wet spinning technology for producing high-quality hemp/cotton blend yarn

In recent years, hemp textiles have gained attention as a sustainable alternative to cotton. However, the uneven fineness and length of hemp fibers, along with their stiffness, adversely affect spinnability and exacerbate yarn evenness and hairiness, particularly due to short fibers. This study introduces a modified sustainable droplet-wet spinning technology aimed at enhancing hemp yarn quality, with a primary focus on reducing yarn hairiness. Implemented on a ring spinning machine, the technology utilizes a syringe connected to an adjustable-speed pump, delivering water onto the front top roller. This innovative approach enhances hemp yarn in two ways: firstly, the cohesive force of water promotes the consolidation of short fibers on both sides of the fiber bundle towards the center, thereby condensing the spinning triangle. Consequently, the fibers on both sides of the fiber bundle are more readily drawn into the spinning triangle and twisted to form yarn; secondly, wet hemp fibers possess a lower modulus, rendering them softer and more deformable, facilitating their embedding into the yarn, thereby enhancing yarn tenacity and reducing yarn hairiness. The study systematically investigates the relationship between droplet-wet spinning parameters (water droplet rate, hemp fiber content of the roving, and yarn twist multiplier) and hemp yarn quality. Experimental results reveals that optimal droplet-wet spinning lead to a 22% increase in yarn tenacity and about 50% reduction in hairiness. A higher hemp fiber content in the roving contributes to better performance of droplet-wet spinning technology in enhancing yarn quality. Moreover, droplet-wet spinning enables the production of high-quality hemp yarn at lower twist multipliers, thereby reducing electricity consumption during yarn production. Subsequently, the performance of knitted fabrics made from conventional ring-spun yarn and droplet-wet spun yarn was compared and analyzed. The results indicate that fabric made from droplet-wet spun yarn exhibits an approximately 8% increase in bursting strength and a one-level improvement in pilling resistance. This research highlights the potential of droplet-wet spinning technology to enhance hemp yarn quality and promote sustainable textile production.

A novel method for reducing yarn hairiness with dynamic and static friction rollers on the yarn guide

Fiber torsional control is critical for reducing the hairiness of high-quality yarns during the yarn formation process. However, the applied fiber torsion that facilitates fiber motion and transfer in conventional ring spinning is still under exploration. In this study, we designed a device with dynamic- and static-friction rollers for reducing harmful hairiness. The key mechanisms and mechanical model of the applied forces on fiber torsion and motion contacting dynamic- and static-friction rollers were theoretically analyzed. Exceptional fiber torsion was obtained by creating gradient friction resistance from the varied applied pressures while providing full internal and external transfer to forcibly capture and trap exposed fibers into the main yarn body. Compared to conventional ring-spun yarns, yarns spun by the dynamic-friction roller exhibited reduced harmful hairiness, improved tensile properties, a tighter yarn surface, and improved yarn irregularity. However, the excessive force applied by the static-friction roller deformed exposed fibers to cause fiber accumulation and fiber loss, resulting in reduced yarn performance. These results can be used to develop novel spinning methods for various fiber materials for high-quality yarn production.

Numerical Simulation of Fiber Motion in the Condensing Zone of Lateral Compact Spinning with Pneumatic Groove

Abstract Lateral compact spinning with pneumatic groove is a spinning process to gather fibers by common actions of airflow and mechanical forces. Compared with ring spinning, it can more effectively reduce yarn hairiness and enhance yarn strength. However, fiber motion in the agglomeration area is complex. And, it is important to establish a new fiber model to accurately describing the fiber motion. The objectives of this research were to create a new fiber model to simulate the agglomeration process, to analyze yarn properties of the lateral compact spinning with pneumatic groove, and to compare with other spinning yarns through a series of tests. The new fiber model was based on the finite element method implemented in MATLAB and was to show the fiber motion during the agglomeration area. The simulation generated results were close to the real motion of fibers in spinning. In the lateral compact spinning with pneumatic groove, fiber bundle through the agglomeration area can be gathered, and the output of the fiber bundle was nearly to cylinder before yarn twisted. The experiments demonstrated that the lateral compact spinning with pneumatic groove can improve the yarn properties: increase the yarn twist, enhance the yarn strength, and reduce the yarn hairiness.

Twist-dependent behavior of helical-shaped elastic composite yarns containing metal wire produced on a modified ring spinning system

Herein, the effect of twist on physical properties such as tensile, hairiness and wicking behavior of our reported tri-component elastic-conductive composite yarns (t-ECCYs) was systematically studied. Experimental results revealed that an optimum twist value provided the maximum yarn strength. A positive relation between extension at break and twist was observed. Significant differences in the tensile behavior is established. Two-parameter Weibull distribution and boxplots were used to quantify the variation in yarn strength. The role of spinning geometry and variation in twists on hair formation was highlighted, with an increase in twist reducing yarn hairiness. In addition, t-ECCYs with higher twist exhibited poorer wickability, and there was a gradual increase of the equilibrium height of yarn under extension. Importantly, the results demonstrated that the Laughlin-Davies wicking model was valid for t-ECCYs under tested conditions. It is promising that the as-fabricated t-ECCYs is prerequisite for the next wave of smart yarns and large-scale stretchable protective devices, such as superstretchable helical-structured yarn heaters and elastic electromagnetic shielding fabrics.

Performance improvement of charkha spun crossbred wool yarn using siro spinning

Indian decentralized wool sector commonly deploys new model charkha (NMC) to produce woollen yarn. It is difficult to obtain the maximum realization of native wool fibre properties into a single yarn spun on a ring spinning system. This is due to the shorter length and higher fibre diameter of indigenous and crossbred wool in comparison to that of Australian Merino wool. A study was made on siro-spinning attachment to NMC charkha to improve quality of yarn produced from crossbred wool. The yarn quality performance was measured in terms of tenacity, elongation, evenness and hairiness. It was observed that siro attachment improved the yarn quality of crossbred wool over the conventional NMC spun yarns. Tenacity and elongation were improved by >38% and 65%, respectively. The doubling effect in siro spinning masks the short length of cross-bred wool and thereby improves yarn strength. The doubling effect also contributes to reduce yarn hairiness and imperfections. Thus, yarn evenness was found better for siro attachment fitted charkha yarn than conventional charkha spun yarn. The attachment is easy to link with existing NMC and hence recommended for spinning of all native and crossbred wool.

An adhesive-aided ring spinning for improving cotton yarn quality with the aid of sodium carboxymethyl cellulose solution

An adhesive-aided ring spinning was developed to improve cotton yarn quality through the wetting and adhesion effect of an adhesive solution, namely, sodium carboxymethyl cellulose solution on fibrous strand in yarn formation zone during spinning process. The spinning mechanism of the adhesive-aided ring spinning with sodium carboxymethyl cellulose solution was analyzed, and the effects of two factors, that is, speed ratio (the ratio of the linear surface velocity to the output speed) and sodium carboxymethyl cellulose concentration, on the yarn performance are investigated. The experiment results reveal that the adhesive-aided ring spinning with sodium carboxymethyl cellulose concentration of 0.7% can significantly reduce yarn hairiness indicated by the hairiness S3 value reducing to 69% and still showing a prominent reduction (65%) after winding process. It has been found that a slightly faster linear surface velocity of the cylinder of the adhesive-aided ring spinning compared with the output speed of the yarn is more beneficial to the reduction of yarn hairiness S1+2 value. Meanwhile, the higher sodium carboxymethyl cellulose concentration also contributes to a higher breaking strength (increasing from 18.24 to 21.12 cN/tex) and lower breaking elongation (reducing from 4.98% to 4.08%). The abrasion resistance of adhesive-aided ring spun yarns also shows an obvious improvement of 12.8%. Therefore, the newly developed adhesive-aided ring spinning with the sodium carboxymethyl cellulose solution provides an effective method to enhance the quality of cotton yarns.

Reducing yarn hairiness in ring spinning by an agent-aided system

An agent-aided system (AAS) for improving comprehensive properties of ring spun yarns with the aid of viscosity and surface tension of the agent is reported in this paper. The mechanism of the humidification and friction process of the AAS was investigated, and related experiments were also carried out to verify the mechanism of analysis. The results confirm that the AAS can attach the fiber ends protruding out of a yarn body on the yarn surface and assist in twisting the fiber ends back into the interior of the yarn body, resulting in a significant reduction of the modified ring spun yarn hairiness. Moreover, the yarn hairiness is prominently reduced after the winding process. The experimental results also show that a speed ratio of 1.3 between the rotating speed of the cylinder and the output speed of the yarn leads to the greatest extent of harmful hairiness reduction (34%), which also corresponds to optimal modified yarn tenacity. Meanwhile, the modified ring spun yarns show a tight and smooth appearance, and the yarn evenness has no deterioration. In addition, the AAS is applicable to both cotton and viscose yarns with different yarn counts. Therefore, the AAS can potentially be used to reduce yarn hairiness for ring spun yarns and enhance the quality of ring spun yarns in the textile industry.

The mechanism of hairiness reduction in offset ring spinning with a diagonal yarn path

Reducing yarn hairiness on a ring spinning machine generally involves an investment and ongoing process cost. Although conceptually successful, the cost factor associated with existing technologies has led to exploration for new ways of reducing hairiness. Offset spinning is an outcome of one such novel initiative in which the spinning triangle geometry is altered by diagonally offsetting the yarn path during spinning. This technique has been reported to reduce hairiness but a consensus on a specific direction of offset (left or right) remains pending as its underlying mechanism is still not completely understood. In this study, we developed an experimental setup to image a spinning triangle geometry in detail and observed the effect of offsetting its shape on fiber path. It was found that the direction of offset (left or right) in combination with a specific twist direction (S or Z) can result in a complete change of yarn twist configuration (Archimedean or Fermat's spiral), which ultimately controls hair generation tendency during spinning. On the basis of agreement between imaging observations and hairiness parameter results obtained from yarns spun with different offset conditions, a mechanism of hairiness reduction and preferred direction of offset is proposed.

Research on the Performance of a Drafting Device for the Four-Line Compact Spinning System

2Key Laboratory of Eco-Textile, Ministry of Education, Jiangnan University, Wuxi 214122, P. R. China **E-mail:gaowd3@163.com Abstract Compact spinning is one of the most important improvements of traditional ring spinning, which is implemented by adding a fibre condensing device to condense the fibre bundle and decrease the spinning triangle, thereby improving the qualities of yarn. Pneumatic compact spinning is the most widely used compact spinning method at present. Four-line compact spinning is one of the most important kinds of pneumatic compact spinning, which is implemented by using a Lattice apron to achieve fibre condensing, decrease the spinning triangle and improve the yarn qualities, especially reducing yarn hairiness. In this paper, the performances of drafting devices for Four-line compact spinning were studied. First the structure and performance of an SDDA2122PH pneumatic cradle equipped with a new kind of block top roller retaining bar were discussed and the pressure distribution of the cradle presented firstly. Then 7.3 tex T65/JC35 was spun on an EJM128K spinning frame equipped with an SDDA2122PH pneumatic cradle, the pressure distributions measured, and the spun yarn qualities were measured and analysed accordingly. Then the acting mechanism of three kinds of top pin: a common top pin without a press bar, a top pin with a front pressure bar, a top pin with a back pressure bar, with respect to yarn qualities was analysed firstly, and then JC 18.2 tex, JC60/T40 18.4 tex and T 18.4 tex yarns were spun on an EJM128K spinning frame equipped with different top pins. Then the qualities of the spun yarns were analysed according to the acting mechanism of the top pin. The results show that by using the new block top roller retaining bar, the pressure of the pneumatic cradle is larger and more stable, thereby improving the spun yarn’s comprehensive qualities. For cotton yarn, we can reduce yarn hairiness by using a top pin with a pressure bar; for chemical fibre and cotton blended yarn, yarn strength can be improved by using a top pin with a pressure bar, and for chemical fibre pure yarn, the usage of a top pin with a pressure bar is beneficial for improving yarn strength and evenness, but not for yarn hairiness and yarn thin and thick places.

Partially gelatinized corn starch as a potential environmentally friendly warp-sizing agent

Partially gelatinized corn starch (PGCS) was used for sizing cotton yarn in the search for potential sustainable and environmentally friendly warp-sizing agents as substitutes for poly vinyl alcohol. PGCS was prepared by a constant temperature method (CTM). The viscosity stability of PGCS was investigated and characterized by wide-angle X-ray diffraction, differential scanning calorimetry, polarized light microscopy and laser diffraction particle size analyzer. The results indicated that the viscosity of CTM65 (starch milk held in a water bath shaker at 65 °C for 30 min) was stable. The cotton yarn was sized by PGCS (CTM65) on a cylinder slasher sizing machine. Scanning electron microscopy indicated that starch granules on the surface of the yarn had completely gelatinized and formed a film when the yarn was treated via the No. 2 drying cylinder (to reduce yarn hairiness). This research supports the idea that PGCS could improve the viscosity stability of native starch paste and have potential as an environmentally friendly warp-sizing agent.

Dynamics of the Ramie Yarn Hair in the Nozzle of the JetWind Process and Effects of Some Nozzle Parameters

The technique of reducing yarn hairiness using an air-jet nozzle on the winder (JetWind) is a combination of the ring and air-jet spinning technologies. The dynamics of the hair inside the nozzle plays an important role in the JetWind process. In this study, a dynamical model for the coupling between a protruding surface hair on the ramie yarn and the airflow in the JetWind process is developed. Based on the model, numerical simulation of the dynamics of the hair in the nozzle is performed and the principle of reducing yarn hairiness is theoretically shown. The simulation result is validated by the experimentally captured motional configurations of the hair in the nozzle using high-speed photography technique. The effects of two nozzle parameters—the injector angle and yarn passage diameter on the dynamics of the hair and in turn, yarn hairiness are investigated by both numerical simulation and experiments.

Research on shape of spinning triangles in the ring spinning system

Ring spinning is the most widely used yarn spinning method at present. Spinning triangle is a critical area in the ring spinning process of staple yarn, in which the geometry influences the distribution of fiber and fiber mechanical properties in the spinning triangle directly, and determines the qualities of spun yarn. Therefore, some new modified ring spinning methods have been appeared gradually by changing the spinning triangle actively. In this paper, the qualities of yarn spun by common ring spinning and two kinds of modified ring spinning were studied by analyzing the shapes of spinning triangle. First, 18.2tex cotton yarns were spun on FA507B ring spinning frame with three different spindle speeds and leading distances of top roller, and corresponding spinning triangles were captured using a high-speed camera system OLYMPUS i-speed3 and one kind of transparent front top roller. Then, the qualities of yarn produced by modified FA507B ring spinning system with four-line rollers compact spinning device and a kind of airflow twisting device were analyzed, respectively. 29.2tex, 14.6tex, 9.7tex yarns, and 18.2tex yarns with three negative pressures 1800, 2200, and 2600 Pa were spun, respectively, and corresponding spinning triangles were captured and analyzed comparatively. It is shown that using compact spinning device, the spinning triangle is reduced greatly, and with the increase in negative pressure, the spinning triangle is reduced gradually. Furthermore, 18.2tex yarns were spun on FA507B ring spinning frame and FA507B ring spinning system modified by a kind of airflow twisting device with airflow pressure 0.1Mpa and 0.05Mpa and two different swirling directions including anticlockwise and clockwise, and corresponding spinning triangles were captured and analyzed. It is shown that for the Z (S) twisting spun yarn, under the effects of the clockwise (anticlockwise) airflow, the spinning triangle can be reduced and benefit for reducing yarn hairiness, while under the effects of the anticlockwise (clockwise) airflow, spinning triangle is more symmetric and benefit for reducing the yarn torque possibly.

Improvement in yarn hairiness by the siro-jet spinning method

Hairiness affects the post-spinning processes and fabric appearance. In order to reduce the yarn hairiness, the present work attempted to design and develop an air nozzle that can be easily attached on to the sirospun spinning system. The system, based on a nozzle attachment to the sirospun spinning system, is named the siro-jet. In our previous studies, the nozzle was used in ring and compact spinning processes and the changes in yarn properties were analyzed. In this study, various nozzles having different injector angles, main hole diameters, injector diameters, number of injectors, nozzle shapes and injector positions were used and siro-jet yarns were produced at different air pressure levels. At the end of the experiments, it was determined that there is an optimum value for each nozzle parameter, and that the number of injectors and injector position play the most important roles in reducing yarn hairiness, whereas nozzle shape shows the weakest effect. On the other hand, the findings showed that it is possible to get lower hairiness values by different modifications on the same nozzle design. Considering the hairiness results, a constant was defined indicating the relationship between nozzle structural parameters and hairiness of the yarns to ease the nozzle design efforts. Depending on nozzle type, the siro-jet spinning system truly improves the yarn hairiness by 40–75%. In the literature, many researchers used an air nozzle in the spinning and also the winding processes. However, the combination of the air nozzle and sirospun spinning system in this manner is still not a common application.

Effect of Nozzle Structural Parameters on Hairiness of Compact-Jet Yarns

Hairiness significantly influences the appearance of yarns and fabrics. New methods and spinning systems have been offered to reduce it. Nevertheless, there is still the quest for easy, low-cost processes to produce good quality yarns with reduced hairiness. Therefore, due to its considerable importance for spun yarns, we worked on a new spinning method to decrease yarn hairiness. Many researchers have been studying the use of air nozzles in the spinning and also the winding processes, and they indicated that hairiness decreases by up to 40–50%. From this point, we investigated the use of an air nozzle on a compact spinning system and discussed the effect on yarn hairiness. The nozzle was positioned at the exit of the drafting system on a RoCoS compact spinning system and pressurized air was fed into the nozzle by the compressor during spinning. We called the combination of an air nozzle and a compact spinning system a Compact-Jet spinning system. In the literature, there are no such trials. At the end of the study, it was determined that a Compact-Jet spinning system truly improves hairiness by up to 40% in comparison to the compact spinning system and by up to 70% compared with the conventional ring spinning system. Regarding the nozzle structural parameters, the changes in hairiness indicate that the main hole diameter and nozzle outlet design make the most important contributions in reducing yarn hairiness; whereas the injector angle and nozzle head type show weaker effects. As a result, the Compact-Jet can be considered as an innovative spinning system providing the opportunity to produce less hairy yarn. Additionally, we believe that this study makes an important contribution to the research activities in the spinning field and its associated literature.

Affect of Application of Hairiness Reduction Equipment on Winding Quality

In order to reduce yarn hairiness of spooling procedure and improve the quality of knotless yarn, contrast experiments, under the given standard test conditions, is performed among several cheese with or without airflow hairiness reduction equipment (HRE); analyzing and discussing the application effect and affect of HRE on yarn quality indexs. It is found from the investigation that the application of airflow HRE can effectively reduce yarn hairiness and also reduce yarn’s CV value of tenacity and improve its minimum tenacity, which can decrease ends’ breakage and machine suspension during high speed warping and high speed weaving production and improve weaving efficiency and appearance quality of fabric. Through analytic comparison, the application of airflow HRE will slightly increase yarn neps, but it’s still an effective method for reducing yarn hairiness and improve fabric appearance quality and weaving production efficiency.

Reducing Yarn Hairiness in a Modified Ring Spinning Yarn Path by Various Offsets

Spinning triangle is a critical region in the spinning process of yarn. Its geometry influences the distribution of fiber tension in the spinning triangle and the properties of spun yarns, such as the yarn breakage and hairiness. In this paper, the relationships between the spinning angle and yarn properties especially the yarn hairiness were investigated under various horizontal offsets. The properties of spun yarns produced by the modified system were evaluated and analyzed. Both left diagonal and right diagonal yarn arrangements were examined. The results indicate that the right diagonal yarn path leads to reduce yarn hairiness but the left diagonal yarn path leads to increase yarn hairiness; the breaking force of yarn changes little; yarn evenness deteriorates slightly with the changes of offset.

Stochastic Simulation of Hairiness with Compact Spinning Yarn

Reducing yarn hairiness is the greatest ascendancy for compact spinning. Based on the test of fiber length distribution, the hairiness of compact yarn is simulated in order to study the rule of hairiness producing. The hairiness of different fineness yarn is simulated by changing the twist factory and the diameter of yarn and the hairiness of different kinds of yarns such as compact yarn and ring spinning yarn are simulated by changing the transition probability of fiber. The simulation data are in accordance with the experimental data. It can make prediction about yarn hairiness according to the fiber length distribution in order to guide production.

Trajectories of fibers and analysis of yarn quality for compact spinning with pneumatic groove

To study the motion trajectory of a fiber bundle in the flow field of compact spinning system with pneumatic groove, the computational fluid dynamics model was established and resolved by numerical computation using FLUENT software. The dynamics of the infinitesimal element of a fiber in the flow zone was also established. The dynamic model was solved by utilizing the self‐designed MATLAB procedure, and the motion trajectory of the fiber in the flow zone was derived. Results of this research confirmed that before the fiber bundle reaches the groove, it is condensed only by the effect of airflow, and when sliding into the groove, it is affected by both airflow and the shape of the groove. Edge fibers of the fiber bundle are condensed by airflow, and the condensing width of fibers is dependent upon the effect of air flow. The position of fibers of different widths change as a result of airflow, and the phenomenon of migration of fibers takes place in the section of the fiber bundle. Compared with the conventional ring‐spun yarn, both the tensile strength and the breaking strength of the compact‐spun yarn are enhanced, in particular by reducing yarn hairiness.

Some studies on hairiness reduction of polyester ring spun yarns by using air-nozzles during winding

This paper reports on the hairiness reduction of polyester yarns at winding using air-nozzles. Three yarns of the same count were spun each from fibres of 1.0, 1.2 and 1.4 deniers respectively. Using a CFD (computational fluid dynamics) model, airflow inside the nozzles is simulated to explain the role of nozzle parameters viz., axial angle of air inlets and yarn channel diameter on yarn hairiness reduction during winding. Air drag forces acting on hairs are calculated. Transverse drag forces acting on hairs play a major role in bending the hairs. Vortex nature of air and air velocity profile inside the nozzle are the important phenomena in reducing yarn hairiness. Box and Behnken factorial design of experiments is used to optimize nozzles parameters, fibre denier, and air pressure to maximize the hairiness reduction. Axial angle of 45° for air inlets, 2.2 mm yarn channel diameter, 1.4 denier fibre, and 0.9 bar (gauge) air pressure are the combinations to get maximum reduction in S3 hairiness values of nozzle wound yarns. Fibre denier is a major influencing factor in reducing yarn hairiness.

Studies on reduction of yarn hairiness by nozzles in ring spinning and winding by airflow simulation

Reduction of yarn hairiness by nozzles in ring spinning and winding is a new approach. Simulation of the airflow pattern inside the nozzles provides useful information about actual mechanism of hairiness reduction. The swirling air current inside the nozzles is capable of wrapping the protruding hairs around the yarn body, thereby reducing yarn hairiness. Since production rate of winding is very high and the process itself increases yarn hairiness any method to reduce the hairiness of yarns at this stage is a novel approach. A CFD (computational fluid dynamics) model has been developed to simulate the airflow pattern inside the nozzles using Fluent 6.1 software. In this study, both S- and Z-type nozzles having an axial angle of 50° and diameter of 2.2 mm were used for simulation studies. To create a swirling effect, four air holes of 0.4 mm diameter are made tangential to the inner walls of the nozzles. S- and Z-twisted yarns of 30 tex were spun with and without nozzles and were tested for hairiness, tensile and evenness properties. The total number of hairs equal to or exceeding 3 mm (i.e. the S3 values) for yarn spun with nozzle is nearly 49–51 % less than that of ring yarns in case of nozzle-ring spinning, and 15 % less in case of nozzle-winding, while both the yarn types show little difference in evenness and tensile properties. Upward airflow gives best results in terms of hairiness reduction for nozzle-ring and nozzle wound yarns compared to ring yarns. Yarn passing through the centre of the nozzle shows maximum reduction in S3 values.