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Most researchers have neglected the effect air-drag force on yarn tension during rotor spinning. This paper aims to study the effect of rotor air-vacuum pressure in conjunction with opening roller speed and yarn linear density on the yarn tension generated during the rotor spinning, which has established their significant influences on both the mean and the peak tension.This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition.

The dynamic measurements on yarn tension at the exit of the doffing tube were carried out by using an electronic capacitive yarn tension meter during rotor spinning. The derived experimental data were fitted into equations to construct the response equations and to work out the coefficients of multiple correlation between the data and the predicted equation for both the mean and the peak tension. Various surface plots were constructed by using those response surface equations, so as to study the effect of variables on yarn tension generated during the rotor spinning.

The study has established that the rotor vacuum is responsible in causing a change in yarn tension, it increases with the decrease in air-vacuum inside the rotor. The involvement of the opening roller speed in altering yarn tension during rotor spinning has been proved. As the opening roller speed changes, so does the air stream surrounding the opening roller speed with consequent alteration of the centrifugal force generated due to the rotation of the rotor. The centrifugal force and, hence, the yarn tension generated in the rotor will be simultaneously affected by both the rotor relative vacuum and the opening roller speed.

This is a structured experimental study to verify the influence of air-drag force generated during rotor spinning on yarn tension. Very limited theoretical work has been carried out in this direction as reported in the introductory part of the paper. The result of the present study will encourage future researchers to revisit the theory on generation of air-drag force during rotor spinning and work out a new formula.

Next only to the conventional ring spinning system, the rotor spinning holds the second place in the share of global yarn production. Because of its advantage of lower cost of production and amenability to automation, the rotor spinning has gained acceptance in spun yarn production, particularly for spinning coarse and medium counts of yarns. Currently, it has acquired about 25 per cent share in the world’s spun yarn production. As many of the rotor machine variables significantly affect fibre configurations and, subsequently, the yarn properties by influencing the airflow characteristics inside the rotor unit, the study of yarn tension during rotor spinning and its analysis assumes a significance.

Rotor spinning is a relatively new and faster method of conversion of discrete fibres into continuous staple yarn and, subsequently, various textiles and garments. Its yarn is distinct and a bit different compared to the conventional ring yarn. It has got wide acceptance in the market and fashion. As such, the spinning sector that converts fibres into yarns is an important industry world over, providing employment to many. Besides, being the basic operation in the fibre value chain, it supports many downstream activities, including human clothing and fashion. Thus, the research on rotor spinning, particularly the yarn engineering to produce better products will be helpful to strengthen and grow the textile value chain.

This is an original research study. The magnitude and the direction of the air drag on the yarn during rotor spinning is very difficult to assess. Thus, most researchers for the sake of simplicity in analysis have neglected its effect on yarn dynamics, but a few of them have taken note of it in their theoretical propositions. However, no experimental result has been reported so far in the literature, supporting the influence of such air-drag force on yarn tension in the rotor spinning. In fact, none of the above studies have considered the induced effect of centrifugal force caused because of the rotation of the opening roller on the airstream that flows from the transfer channel inlet into the rotor because of its partial vacuum, causing consequential effects on air-drag force and tension in the yarn inside the rotating rotor. This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition.

The tension variations across the width of the weaver's beam cause uneven tension in the fabric formation zone. As a result of the tension variation, the woven fabric tends to have fabric defects, such as non-uniform fabric density and differential dye take–up at various places on the fabric. As the warp ends are continuously subjected to varying tensions, warp breakage frequently occurs. As a result, the quality of the fabric produced suffers and there is reduced loom efficiency. However, uniformity in the fabric density is crucial, especially for technical and smart textiles. In this paper, the authors have attempted to model the varyingtensions across different segments of a warp sheet under a set of assumptions and derived a linear model. Furthermore, a prototype of an automatic tension control device is instrumentedwith two different positions which are located one meter apart and allows the tension variations across the warp-sheet to be practically observed. The measured average tension shows that variations in the internal tension on different segments of the warp-sheet can be minimized or even completely eliminated over time. With the implementation of a related experiment, the authors have shown the effectiveness of this automatic tension controller and its strong implications for the industry.

In order to help explain experimental findings related to the stabbing- and ballistic-penetration resistance of flexible body-armor, single-yarn pull-out tests, involving specially prepared fabric-type test coupons, are often carried out. The purpose of this paper is to develop a finite-element-based computational framework for the simulation of the single-yarn pull-out test, and applied to the case of Kevlar® KM2 fabric.

Three conditions of the fabric are considered: neat, i.e, as-woven; polyethylene glycol (PEG)-infiltrated; and shear-thickening fluid (STF)-infiltrated. Due to differences in the three conditions of the fabric, the computational framework had to utilize three different finite-element formulations: standard Lagrangian formulation for the neat fabric; combined Eulerian-Lagrangian formulation for the PEG-infiltrated fabric (an Eulerian subdomain had to be used to treat the PEG solvent/dispersant); and combined continuum Lagrangian/discrete-particle formulation for the STF-infiltrated fabric (to account for the interactions of the particles suspended in PEG, which give rise to the STF character of the suspension, with the yarns, the particles had to be treated explicitly).

The results obtained for the single-yarn pull-out virtual tests are compared with the authors’ experimental counterparts, and a reasonably good agreement is obtained, for all three conditions of the fabric.

To the authors’ knowledge, the present work represents the first attempt to simulate single-yarn pull-out tests of Kevlar® KM2 fabric.

This study aimed to determine the peak impact force and force attenuation capacity of weft-knitted spacer fabrics intended for padding that can be used for human body protection against impact.

A total of five weft-knitted spacer fabrics were fabricated with four different diameters of nylon monofilament yarns and one doubled monofilament yarns, respectively. The impact performances of the weft-knitted spacer fabrics were tested using a drop test method with a customized test rig to simulate falling. Impact tests were conducted on single- and multilayered experimental spacer fabrics to investigate the peak impact force and force attenuation capacity.

It was found that weft-knitted spacer fabric with a coarser or larger diameter of monofilament spacer yarn generated lower impact force and higher force attenuation capacity, thus resulting in better impact performance. Greater force attenuation can be achieved by utilizing a higher number of spacer fabric layers. However, the increase in thickness must be considered with the spacer fabric end use.

This study employed relatively coarse nylon monofilament yarn as spacer yarns to gain knowledge on the impact performance of weft-knitted spacer fabrics compared to warp-knitted spacer fabrics which are more common. The results showed that the diameter of spacer yarn significantly influenced the impact performance of the experimental weft-knitted spacer fabrics. These results could be useful for designing and engineering textile-based impact protectors.

The purpose of this review paper is to define the dominating factors (such as fiber, yarn, fabric structure, sewing thread, sewing needle and machine parameters) that affect the seam damages and causing defects. It also describes the various explanations of sewing defects in garment production and critically analyzes them for optimum selection of parameters and speeds for minimizing such faults. Hence, the knowledge of various factors which affect the sewing damages/defects will be helpful for garment manufacturers/researchers to know influence of the parameters and control the quality of producing seam.

This section is not applicable for a review paper.

Sewing damages such as needle cut and other sewing damages/defects are studied mostly in woven fabric. There are very few studies conducted on knitted fabric sewing damages/defects. The sewing damage problems do not have single solution that is capable of removing these damages in fabric. All the determined and affecting parameters related to fiber, yarn, fabric construction, sewing thread and sewing machine must be examined to design appropriate remedial measurement related to machine design, fabric parameters and sewing thread. This could help in minimizing or eliminating the needle cut and other sewing damage problems.

It is an original review work and is helpful for garment manufacturers/researchers to reduce the defects and be able to produce good quality seam.

This paper aims to extracted sericin from the cocoons of Bombyx mori silkworms, and sericin powder was applied onto drawn textured polyethylene terephthalate (PET) yarns as a spin finish. The reactivity on the surface of PET yarns was analyzed through Fourier transform infrared spectrophotometry–attenuated total reflectance (FTIR-ATR) and dyeing with methylene blue as a reactive dye. Also, investigations were conducted on the effects of sericin, citrc acid (CA) (as a crosslinking agent), and sodium hypophosphite (as a catalyst) concentrations on some properties of false-twist textured PET yarns.

A false-twist texturing machine (Scragg-Shirley minibulk, England) was used with the draw ratio of 1.05, heating temperature of 120°C, texturing speed of 100 m min⁻¹ and applied twist of 3,000 TPM. The aqueous extraction of sericin was carried out by the boiling of the raw silk in distilled water with L:R: 40:1 for 120 min. The aqueous solution was filtered with a filter paper to remove the impurities and insoluble fibroin. Finally, the sericin solution was freeze-dried to obtain the sericin powder. The sericin solution was applied on the drawn textured PET yarns using the “pad-dry-cure” method.

Sericin fixation onto the PET yarns was confirmed by FTIR-ATR. The results showed that there were no significant changes in the tensile strength, linear density, crimp contraction and crimp modulus, elongation at break and shrinkage. In contrast, a substantial increase was observed in moisture regain, vertical wicking, dye uptake and ultraviolet protection. There was also a reduction just in the electrical resistivity, in the presence of sericin.

Although sericin has been known to have numerous beneficial properties, its application in textile industry as a spin finish has not been reported yet.

Friction is considered to be one property of cloth that has considerable importance in the fields of both technological and subjective assessment for surface properties of textile fabrics. The purpose of this study is to investigate the affective aspects of yarn and fabric structural parameters on the behavior of surface friction of plain woven fabrics.

In this study, nine varieties of half-bleached cotton plain-woven fabrics with three weft yarn count (tex) and three weft thread density (ppc) are produced and will be examined for their frictional characteristics. The surface frictional properties of plain-woven fabrics were measured by using Kawabata (KES-Fb4) testing instrument. The ANOVA analysis is used to determine how yarn (count) and fabric (density) structural parameters does influence the surface friction properties of the fabrics. Also, the interaction effects between the factors (count and density) on the response variable (surface friction) of plain-woven fabrics.

The findings of this study revealed that the effects of weft yarn count and pick-density have statistically significant on the frictional behavior of the fabric surface properties at a 95% confidence interval. Thus, weft yarn count has a positive correlation with both coefficient of friction (MIU) and mean deviation of coefficient of friction (MMD) on frictional behavior of the fabric surface properties. On the other hand, pick density has a negative correlation with both MIU and MMD on frictional behavior of the fabric surface properties. The weft count, pick density and their interactions (Count X Density) have multicollinearity in the experiment term because the variance inflation factor values were greater than one.

The findings of this study can be routinely used across the textile industries and laboratories to provide a fundamental understanding regarding the surface frictional properties of the woven fabric for different end applications concerning the yarn structural parameters and fabric structural parameters. And the relationship of count and density with surface friction of plain woven fabrics.

The conversion of fabric into a garment involves many interactions such as the selection of suitable sewing thread, optimization of sewing parameters, ease of conversion of fabric into the garment and actual performance of the sewn fabric during wear of the garment. The adjustment of all sewing parameters is necessary to ensure quality. The purpose of this paper is to define the parameters that affect seam quality comprehensively.

This study primarily focuses on the studies dealing with the effect of various parameters on-seam quality in detail. A systematic literature review was conducted.

The interactions between parameters may lead to different results than the effect of a single parameter. In addition, changing some parameters may have a positive effect on one element of seam quality while having a negative effect on another. For this reason, it is very important to properly select the parameters according to the specific end use of the garment products and also to consider the interactions.

The knowledge of various factors that affect seam quality will be helpful for manufacturers to improve production performance and to be able to produce high-quality seam.

Presents the study of the relationship between the deformation of the sewing thread and built‐in fibres as a consequence of a thread loading in the sewing process. The influence of the stitching speed and different twist numbers of PES thread on the alteration of the mechanical properties of the fibres twisted in the thread was studied for that purpose. On the basis of the received results it was found that with an increase in the number of the thread twist, the breaking tenacity and initial elasticity modulus of the fibres decrease, while the resulting deformation of the sewing thread between the sewing process was reflected as a decrease in the fineness and breaking extension of the fibres and as an increase in the value of the initial elasticity modulus of the fibres.

This paper aims to predict fatigue life and fatigue limit of fiber-reinforced ceramic-matrix composites (CMCs) with different fiber preforms, i.e. unidirectional, cross-ply, 2D-, 2.5D- and 3D-woven, at room and elevated temperatures.

Under cyclic loading, matrix multicracking and interface debonding occur upon first loading to fatigue peak stress, and the interface wear appears with increasing cycle number, leading to degradation of the interface shear stress and fibers strength. The relationships between fibers fracture, cycle number, fatigue peak stress and interface wear damage mechanism have been established based on the global load sharing (GLS) criterion. The evolution of fibers broken fraction versus cycle number curves of fiber-reinforced CMCs at room and elevated temperatures have been obtained.

The predicted fatigue life S–N curve can be divided into two regions, i.e. the Region I controlled by the degradation of interface shear stress and fibers strength and the Region II controlled by the degradation of fibers strength.

The proposed approach can be used to predict the fatigue life and fatigue limit of unidirectional, cross-ply, 2D-, 2.5D- and 3D-woven CMCs under cyclic loading.

The fatigue damage mechanisms and fibers failure model were combined together to predict the fatigue life and fatigue limit of fiber-reinforced CMCs with different fiber preforms.