Compact Spinning in Cotton-based Core-spun Yarn: A Review

In today's world, textile outfits are chosen not only for their functional properties but also for their comfort. As cotton is synonymous with comfort in textile industries, cotton-based core-spun yarn is becoming increasingly popular day by day, where the core element satisfies the functional properties and the cotton sheath provides a good hand feel and comfort. At the beginning of the twenty-first century, researchers developed a new spinning modification known as the compact spinning system to improve yarn quality. In cotton-based compact core-spun yarn, reduced hairiness, unevenness (U%), thick place, thin place, neps, and increased strength are achieved. This will also lead to significant abrasion and piling resistance, higher air permeability, lower thermal resistance, and higher Relative Water Vapor Permeability (RWVP). This review paper illustrates the advantages of spinning cotton-based core-spun yarn in the compact spinning system.

Production of Fine Count Yarns from Some Extra-long Egyptian Cottons on Different Spinning Systems

The current research was carried out to produce fine count yarns from extra-long Egyptian cotton varieties using compact and ring spinning systems.in addition, to compare between compact yarns and ring yarns in terms of their physical and mechanical properties. Three commercial extra-long staple Egyptian cottons Giza92, Giza93 and Giza 96 were used to produce four linear densities of 80, 100, 120 and 140 at 3.6 twist multiplier. Results obtained showed that Giza 92 was surpassed significantly other extra -long staple varieties. It recorded the highest mean values of yarn strength and yarn evenness While, the same variety recorded the lowest mean values of yarn hairiness and imperfections. Compact yarns were much better than yarns spun on the ring spinning in yarn strength, yarn elongation, evenness, yarn imperfections and yarn hairiness. Yarn count 80,s gave higher single yarn strength (20.89cN/tex), yarn elongation (5.03%) and yarn evenness (17.49%) and lower yarn hairiness (2.04) and imperfections than yarn count 140s. Single yarn strength, yarn elongation and yarn evenness were decreased with increasing yarn count. While the number of neps, hairiness, the number of thin and thick places were increased with increasing yarn count. Concerning, the effect of interaction between cotton varieties × yarn counts × spinning systems on yarn quality properties. Yarn count 80s recorded the highest mean values of yarn strength (23.14, 21.1 and 20.2 cN/tex) and yarn evenness (17.72, 16.53 and 16.79%) for varieties Giza92, Giza93 and Giza96, respectively for compact spinning system. Yarn strength at count 80, 100, 120 and 140 correlated negatively and highly significant with micronaire value and maturity ratio.

Numerical and experimental approach towards an energy-efficient compact spinning system

Compact spinning with a lattice apron has recently become a very attractive approach for pneumatic compact yarn production spinning systems. One of the main challenges with use of this method is the high negative pressure that leads to high energy consumption. In response to this challenge, we present a numerical and experimental investigation of the effects of a three-dimensional (3D) printed guiding device on the airflow characteristics and yarn properties. Initially, the 3D numerical model of the compact spinning system was set up based on the real geometrical dimensions. Secondly, the 3D prototype was developed, simulated, and analyzed using Solidworks and Ansys. Ultimately, the design, which exhibited low negative pressure along the model domain, was adopted and then 3D printed to enable further experimental investigation. Airflow analysis results illustrated that when using the guiding device with low negative pressure, the active area of negative pressure was increased. This was due to the existence and the special design of the guiding device that prevented the decrease of the negative pressure with atmospheric pressure. This increased the transverse condensing force, which was beneficial for twisting the free-end fiber around the fiber bundle. Experimental results revealed that the three yarns spun with the guiding device achieved significant energy saving when the guiding device was used. Moreover, these yarns spun with the guiding device had better strength, hairiness, and evenness than those spun without a guiding device. The model developed can be further improved and utilized for commercial purposes, as it significantly reduces energy costs while improving yarn properties.

Investigation into four-roller compact spinning with air damper for improving yarn performance

Compact spinning, as a new kind of spinning technology, has gained wide attention because of its great reduction in spinning triangle and yarn hairiness. In order to meet the demand of high-grade clothing, research on further improving the performance of compact spun yarn is the emphasis. Of all the existing compact spinning systems, the four-roller compact spinning with lattice apron is most widely used at present because of its low cost. Therefore, this paper aims to put forward a new kind of device to improve yarn performance for four-roller compact spinning systems. Related experiments have been done to verify the efficiency of the device, and the mechanism is analyzed by computational fluid dynamics. The numerical simulation shows that the device can change the direction of airflow and increase the velocity in the directions of transverse condensing and thickness. It is shown that the air damper is convenient to use and has potential applications in spinning compact yarns with better performance.

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

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.

Numerical Simulation and Analysis of Airflow in the Condensing Zone of Compact Spinning with Lattice Apron

The airflow field pattern in the condensing zone plays a vital role in the pneumatic compact spinning, which significantly affects the yarn's qualities. This study aimed to analyze the effects of the different negative air pressures on fiber condensing in compact spinning with lattice apron using ANSYS. The results of airflow simulations reveal that by increasing the negative pressure, the flow velocity increases, leading to a more tremendous increase in the transverse condensing effects. Additionally, a better convergence led to reduced fiber width and eliminated the spinning triangle. Experimental results showed that the three yarns spun with the highest negative pressure had better strength, hairiness, and evenness than those spun with lower negative pressure.

Design of three-strand compact spinning system and numerical flow-field simulation for different structures of air-suction guides and suction inserts

This study aims to design a compact three-strand spinning approach as inspired by the twist and compact spinning. In the design process, auxiliary parts of twist and pneumatic compact spinning technologies were modified. First, a three-strand funnel and three-groove delivery cylinder were designed to feed three-strand into the drafting zone and control strand space. Then, air-suction guides and suction inserts with different structures of air-inlet slots were designed to create a separate condensing zone for each of the strands. Different structures of the air-suction guide and suction insert were used for modeling the compacting zone and four different systems were introduced. The effectiveness of compacting zones was discussed according to the numerical flow-field simulation studied with SolidWorks Flow Simulation software. Numerical simulation results showed that creating separate condensing zones for three-strand yarns was achieved with all of the new designs. However, the air-guide with longer air-inlet slot channels provided better flow-velocity components and static pressure values. It was also seen that using the same guide with narrowed slots suction insert results in greater flow-velocity components. In the experimental part, the guide with longer air-inlet slots and narrowed slots of suction insert was produced with a 3D printer and used for compact three-strand production. Properties of the compact three-strand yarns were compared with ring three-strand yarns to investigate compacting effects, and it was seen that better yarn properties were obtained with the compact three-strand spinning.