Ply Yarn Research Articles

Influence that Cyclic Variation of the Friction Characteristic of Double Ply Yarn Gives Surface Fault of the Plain Stitch Fabric

It is well known that the faults such as thin-thick, neps and unevenness in the staple yarn make bad the quality of the fabric that is knitted from the yarn. There is a double ply yarn that have neither thin-thick nor neps and no specific cycle in yarn evenness that cause problem in the plain stitch fabric made from flat knitting machine. For comparison, the yarn which has almost same properties on evenness test as the former yarn and makes no problem fabric is selected. In the case of former yarn, the range of the tension which passes through needles on friction test is wider than that of latter yarn and the tension has a certain cyclic variation. The yarn which has certain cyclic tension variation at passing through the needles is made experimentally and is knitted. These results were shown.

Copper, stainless steel, glass core yarn, and ply yarn woven fabric composite materials properties

A study on physical and mechanical properties of copper core yarn, stainless core yarn, glass core yarn, and copper ply yarn woven fabric composite materials through ANOVA has been reported. Copper, stainless steel, and glass filaments are selected as the core, and cotton is selected as the sheath. The various combinations of copper, stainless, and glass core yarns are produced by DREF II Friction spinning machine, and core yarns are converted into woven fabric composite materials by loom. The physical and mechanical properties of copper core yarn, stainless core yarn, glass core yarn, and copper ply yarn woven fabric composite materials have been measured using various instruments. It is observed that there is strong and significant difference between the tensile strength of warp direction and weft direction of core yarn woven fabric composite materials. The flexural rigidity and bending modulus of core yarn fabric increases with an increase in core content of copper, stainless steel, and glass filament.

Orientation Density Function of Ply yarn

Assuming that the individual fibers in a ply yarn have the form of a doubly wound helix, we simulate the paths of the individual fibers in the yarn. We show the fiber paths as a function of the fiber position in the single yarn, the number of twists of the single yarn and the ply yarn, and the direction of twist for the single yarn and the ply yarn. We also calculate the orientation angle, the orientation density function, and the mean of orientation angle in a ply yarn in order to predict the mechanical properties of ply yarn.

Manufacturing Technique and Physical Property of Metal Wires/ PP Nonwoven Selvedges Complex Ply Yarns and Knitted Fabrics

In this study, nonwoven selvedges served as core yarn which was wrapped with stainless steel wires. Core yarn was added with functional materials such as stainless steel wires or copper wires or both. Functional polypropylene nonwoven selvedges (PNS) complex ply yarns were made using a rotor twister machine. The wrapped density of stainless steel wires was changed as 0.5, 1.5, 2.5, 3.5 and 4.5 turns/cm and the speed of rotor twister was set at 8000 rpm. Shown in the mechanical property test of complex ply yarn, when speed of rotor twister was at 8000 rpm; wrapped density was 2.5 turns/ cm; and functional materials were copper wires and stainless steel wires, complex ply yarns made of polypropylene nonwoven selvedges (PNS) had the maximum breaking force as 47.76N and maximum breaking elongation as 47.93%.

Comparing between Estimating Visual Quality of Plain Stitch Fabric and Friction Test for Double Ply Staple Yarn

It is well known that the results of yarn evenness test informed the quality of the resulting fabric. The unevenness such as thin, thick, nep, and mass periodic change caused bad visual quality of fabric. Evener yarn makes better visual quality fabric. In our previous paper, it was, however, reported that the double ply yarn having little unevenness caused a peculiar manner of bad visual quality of the plain stitch fabric. But, in yarn friction test, this yarn had the wider range of the friction change working between needles and the running yarn than usual yarns. In addition, the friction change had a certain cyclic variation. In case of flat knitting machine, dyeing double ply yarns are generally knitted. After dyeing, evenness test and friction test are seldom applied to the yarn. In this paper, these tests were carried out for the several yarns which were generally knitted by flat knitting machine. Some yarns were added as tested yarns. Those yarns imitated the yarn that caused a peculiar manner of bad visual quality. The result of these examination and measurement was weighed. It was found that there was the correlation between the variety of friction and visual quality of the resulting fabric.

Mechanical Modeling of Tenacity: Application for the Ring and Open-End Plied Yarns

ABSTRACT This work presents an analysis of a mechanical model for cotton plied yarns' tenacity. Results show that the tenacity of a plied yarn depends on the parameters of twisting and the linear density. For verification of the theory, we have also applied this model for the ring and Open End plied yarns. Comparison between experimental data and theoretical predictions showed that the predicted yarn tenacity is in reasonable agreement with experiment results.

Application of topological conservation to model key features of zero-torque multi-ply yarns

During yarn formation by ring spinning, fibres are bent into approximately helical shapes and torque or twist-liveliness is created. The yarn torque causes yarn instability, manifested as snarling or entanglements, and this instability must be controlled during manufacturing processes. Generally, the torque depends on yarn geometric factors such as the yarn twist, linear density and the fibre properties. A practical solution to the problem of twist-liveliness is the formation of a two-fold yarn. This twisting or plying process produces a yarn structure where the energy of the system is determined by purely geometrical constraints of the plied structure and consequently when an energy minimum is reached the plied yarn obtained from the process is torsionally balanced and torque-free. In the present paper, the stability of plied textile yarns will be evaluated using the Topological Conservation law (Fuller, F. B., 1971, Proc. Nat. Acad. Sci. USA, 68, 815–819.) developed to study the post-buckling behaviour of twisted rods by Van der Heijden et al. (Int. J. Mech. Sci., 45, 161–196, 2003). The present work considers the equilibrium configuration of a series of multi-ply twisted yarns (2, 4, and 6 strands) of finite length. Several structural and mechanical properties are highlighted: (i) the influence of structural properties (the number of strands, the strand linear density and strand twist) and the ratio of the torsional and bending stiffnesses of the strands on the balance point in multi-ply yarns. The topological invariant of the twisted yarn (link) is used to calculate the ply and strand properties (writhe) and compared with experimental results obtained at CSIRO. The inter-strand pressure between strands of a multi-ply yarn, a feature of interest for fibre interactions in yarn structures, is also calculated at the balance situation across a range of structural and mechanical conditions.

Effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of ply yarns

AbstractThe amount of ply twist required to bring the surface fibers of the strand parallel to ply yarn axis is half the single yarn twist and, is experimentally verified by viewing the multifilament yarns longitudinally under Scanning Electron Microscope. The effect of single yarn twist and ply to single yarn twist ratio on strength and elongation of two‐ply cotton yarn have been studied. As the single yarn twist increases the tensile strength of the ply yarns with different levels of ply to single yarn twist ratio increases and at 130–140% of normal single yarn twist level, the ply yarns attain almost the same strength. Rate of improvement in tensile strength of cotton two‐ply yarn with respect to single yarn twist is more than that with respect to ply twist. The effect of ply to single yarn and cable to ply yarn twist ratio on strength and elongation of ply and cable multifilament yarns have been studied. Tensile strength of ply and cable multifilament yarns do not vary with the change in ratio of ply to single yarn twist and cable to ply twist respectively, particularly when the resultant yarn is finer. The cosine of average filament inclination to the ply yarn axis and that to the cable yarn axis do not vary much with different levels of ply to single yarn twist ratio and cable to ply yarn twist ratio respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2245–2252, 2005

The novel technology of the functional fabric composed of polypropylene non-woven selvages, polyester filaments and copper wire

Our process and products were innovative and creative. In order to produce multifunctional fibre products, we combined two or more different kinds of fibres, instead of one single fibre, to spin the ply yarn and weave them into fabrics in the hope that the final products would meet our requirements. The process in this research was innovative and high technical. The ply yarn and fabrics we made possessed high performance and diversity, and they were recyclable and practical. The ply yarn consisting of polypropylene non-woven selvages, copper wires and polyester filaments with a rotor twister possessed superior electrical and mechanical properties due to the natural characteristics of the filaments. The ply yarn was produced under different conditions of twister counts and rotor speeds, and then was woven with a rapier loom. By varying manufacturing parameters, the helix angle and tightness of the twist-wrapped yarn were also changed to enhance the mechanical properties and EMI shielding effectiveness. In this paper, the optimum condition for producing the ply yarn wrapped with metallic filaments was under the rotor speed of 8000 rpm and 2.5 turns/cm, and that with polyester filaments was 6000 rpm and 1.0 turn/cm. After the measurement of electromagnetic shielding effectiveness, we found the fabrics that fabricated with the ply yarn could take as the electromagnetic shielding materials. The weight percentage of the metallic fibre was only 3.40–4.45 wt% and the value of the shielding effectiveness was 10–20 dB.

Bending Mechanics of Ply Yarns

In this paper, a coercive couple due to the friction between strands during two-ply yarn bending deformation is derived in terms of the strand and two-ply yarn structural factors using an energy method. The experimental and theoretical results are compared for the multifilament yarn and for various structural parameters as well.

THE NOVEL TECHNOLOGY OF FUNCTIONAL FABRICS COMPOSED OF POLYPROPYLENE NONWOVEN SELVAGE/POLYESTER/STAINLESS STEEL

Nowadays, the Green Environment Protection is popular, and the synthetic fiber nonwoven is recyclable and reusable to fabricate functional products with high additional values. It is because that the synthetic fibers used in the nonwoven industry are almost thermoplastic polymer. In this study, we adopted stainless steel filament as functional metal fiber, polypropylene nonwoven waste as filled material and reinforced it with polyester filament. Our process and products were innovative and creative. In order to produce multifunctional fiber products, we combined two or more different kinds of fibers, instead of one single fiber, to spin the ply yarn and weave them into fabrics in the hope that the final products would meet our requirements. The process in this research was innovative and high technical. The ply yarn and fabrics we made possessed high performance and diversity, and they were recyclable and practical. The functional ply yarn and its fabric responded to the electrical functional demands. The products can be applied on the anti-electrostatic fabric or processed into artificial composites. In this research, the functional ply yarn was produced with an innovative rotor-wrappingtwister. The yarn consisted of polyester filaments, stainless steel filament and polypropylene nonwoven selvages. The speed of the rotor-wrapping-twister and the wrapping counts were the parameters in the manufacturing process. Then the ply yarn was woven into plain fabrics with a rapier loom. Finally, we investigated the tensile properties and maximum breaking strength utilization factors of the fabrics. The maximum breaking strength and elongation of the PS group (core materials were polyester filaments and polypropylene nonwoven selvages, and wrapping material was a stainless steel filament) were better at higher rotor speed (8000 rpm). The influence of the wrapping counts on the tensile properties was different while we used different wrapping materials. After the measurement of electromagnetic shielding effectiveness, we found the fabrics that fabricated with the ply yarn could take as the electromagnetic shielding materials. The weight percentage of the metallic fiber was only 3.52 ∼ 4.58 wt % and the value of the shielding effectiveness was 10 ∼ 25 dB.

Influence of Machine Variables on Two-Strand Yarn Spinning Geometry

Strand convergence angle and strand twist above the convergence point constitute the primary yarn formation condition in two-strand yarn spinning. In order to assess the strand convergence angle and strand twist during spinning, dual-coloured multi filament yarns were fed directly from the front rollers of a ring frame run in a wide range of conditions. A photographic procedure was used to investigate the two-strand yarn spinning geometry and the influences of main machine variables, the spinning tension, the ply yarn twist, and the strand space at the front roller nip.

Factors Affecting Dimensional Properties of Cotton Plain-Jersey Fabrics

The effect of fabric tightness (K) and relaxation treatment on the dimensional parameters (kc; , kw;, ks; =kc; ×kw; and kr; =kc; /kw; ) and the ratio t/l for plain-jersey fabrics is investigated experimentally, using plied yarn of nylon multiple filament, that of cotton yarn, and paralleled cotton yarn.For coarse nylon plain-jersey fabrics, the dimensional parameters are independent of the fabric tightness and the method of relaxation treatment used. The ratio t/l is dependent on the fabric tightness, and independent of the method of relaxation treatment used.For cotton plain-jersey fabrics knitted of plied yarns, the dimensional parameters and the ratio t/l are dependent on the fabric tightness and the method of relaxation treatment used. For these knitted of paralleled yarns, kr is dependent on the fabric tightness, and kc; , kw; , ks; and the ratio t/l are dependent on the fabric tightness and the method of relaxation treatment used.

Effects of Yarn Twist on the Mechanical Properties of Plied Yarn Fabrics

Twisting effect is an important factor determining the mechanical properties and structure of fabrics. An investigation was made of the relation between yarn and fabrics properties in terms of their tensile and bending properties when the resultant count of the plied yarn was varied.1) A high correlation was found between yarn and fabric properties such as tensile, bending, and physical properties (thickness, and weight).2) Surface roughness increases with increasing resultant count of piled yarn. Superficial crepe effect was obtained in coarse yarn fabrics when the constituent single yarns differed greatly in count.3) The bending rigidity of gray and finished fabrics of coarse yarns were greater than those of fine yarn fabrics. The constant (R) indicating the degree of correlation between yarn and fabric in their bending rigidities is expressed as: R=Xf; /N•Xy; where, Xf; : bending rigidity of fabrics, Xy; : bending rigidity of yarns, and bending rigidity of fabrics, N: number of yarns per unit width of fabric.The value of R for cotton/cotton plied yarn fabrics is larger than those for cotton/polyester multi-filament plied yarn fabrics irrespective of the resultant yarn count.

The Torque Generated in Single and Multi-Ply Yarns as a Function of Changes in Yarn Tension

This paper presents a theoretical and experimental investigation of the torque generated in a yarn as a result of a change in applied tensile stress. Single and plied yarn structures are analyzed, and it is shown that for small elastic extensions of a yarn, the change in yarn torque is linearly related to the applied tensile force P and also to the yarn twist. For plied yarns, a ratio of ply twist to single-yarn twist exists, for which the structure is torsionally insensitive to changes in applied tension. An expression is derived, relating this twist ratio to the yarn geometry, and values of 0.33, 0.20, and 0.11 are experimentally verified for 2-, 4-, and 7-ply yarns, respectively.

クレープ織物の設計に関する研究 ＩＩＩ 強ねん諸より糸の形態学的，力学的特性について

An attempt has been made to evaluate quantitatively the twisting shrinkage and the degree of .twisting (i.e., twist contraction force and untwisting moment) of hard plied yarns. Following fundamental equations have been obtained by experiments.1) The twist shrinkage of the plied yarn, Rm, is given by : Rm= (√1+ (2πNR) 2-1) - (k (√D·n/105) 2-k (√D· (n-N) /105) 2) 2) The degree of twisting of the plied yarn, M.T.C., is given by : M.T.C.=√2D (N2+ (n-N) 2) 1/2-√D·nwhere, D : finess of a first twist yarn, n : twist of a first twist yarn in turns per unit length, N : twist of a final twist yarn in turns per unit lengthR : radius of the cylinder on which the center line of a single yarn may exist, andk : experimental constant determined by the twist method and twisting tension.3) The relation between M.T.C. of the dry and wet twisting yarn is given by : M.T.C. of wet twisting yarn=β·(M.T.C. of dry twisting yarn)where, β is an experimental constant determined by k of the dry and wet twisting yarn.

Studies On Reverse Tension Mechanism Of Cheese Dyeing

In this paper reverse tension mechanism were observed. Soft winding is the main criteria of level yarn dyeing. One of the most vital difficulty of Dyeing a yarn package in cheese form is the density variation of the soft wounded packages themselves and also within a package. . In most cases this density variation results unlevelness of dyed package. This type of unlevel is very common for double ply yarn where the density varies significantly. A through investigation had made to suggest effective ways to achieve evenly dens package in soft winding section in a well equipped modern yarn dyeing factory. A new method termed as ‘reverse tension mechanism’ has developed to maintain even density within a package and also at packages themselves .Co-efficient of variance found near 0.3% for the new technique whereas it is more than 1% for the current system. This paper shows that the density achieved by reverse tension mechanism is very uniform at different layers of a package and also at the packages themselves than the conventional machine settings for both carded and combed cotton double ply yarn of finer and coarser count. Keywords: Reverse tension mechanism; Portion density; Package to package & within package; Unlevelness. DOI: http://dx.doi.org/10.3329/diujst.v6i2.9344 DIUJST 2011; 6(2): 42-52

STUDIES ON THE SHRINKAGE OF HANDKNIT YARN

The shrinkage of handknit yarn was studied by using shaking type felting machine. Regarding the effect of yarn twist, it was observed that higher twist, singles as well as ply, resulted lower shrinkage value and contribution of ply yarn twist to shrinkage was nearly constant in spite of variation in single yarn twist.Tensile tests made with handknit yarns felted at various stages give the different typs of break.When it's shrinkage is felted to 20-30% in length, the handknit yarn breaks sharply at places, and stepwise series of higher breaking extensions occur at others. This may be due to the entanglement of the constituent fibres.In the course of felting, untwisting is observed up to 20-30% shrinkage, but not above that.From these observations, it is supposed that up 20-30% shrinkage, untwisting played, main part in the felting of handknit yarn, but above that the entanglement of the fibres could be the main cause.

Some Properties of 50/50 Nylon/Cotton and Nylon/Viscose Blends: Part I: The Strength and Air Permeability of Fabrics Varying in Construction

About thirty experimental nylon/cellulosic fiber blend fabrics were constructed to study the effects of the following variables: cotton vs ordinary and modified viscose; intimate vs plied yarn blends; weave, yarn number and spacing, and twist; untreated vs heavily resin-treated samples, with various add-ons of softener. The grab strength of the nylon/cotton intimate blend fabrics could be related to the weight of the stressed yarn system by the equation: Grab strength, lb = 0.0087 den/in. — 15 (corr. coeff. 0.95) There was no significant effect of the fabric construction or resin treatment on this relationship. The points representing nylon/viscose intimate blend fabrics were generally quite close to this line, but those for nylon/cotton plied yarn blend fabrics followed an equation with the same slope but with an intercept of +30; thus, at an average, they had 45 lb more grab strength than comparable intimate blend fabrics. The tear strength of the untreated, nylon/cotton intimate blend fabrics followed the relationship Tear strength, lb = 0.00036 den/in. — 0.3 (corr. coeff. 0.74) The points above this line were generally those representing satins and relatively coarse yarns; those below, 2/1 twills and plain weave fabrics and/or relatively fine yarns. The same slope with an intercept of −2.5 lb and a correlation coefficient of 0.91 were obtained after resin treatment, indicating an average strength loss of 2.2 lb, and a much smaller effect of fabric construction. The nylon/cotton plied yarn blend and the nylon/viscose intimate blend fabrics had higher tear strength than their nylon/cotton intimate blend counterparts. The air permeability of the blends which contained viscose was generally higher than that of their cotton-containing counterparts. In all blends, the air permeability was reduced by the resin treatment. Within each blend, the air permeability was essentially a function of the closeness with which a fabric construction approached the limit of weavability. Relatively low twist (twist multiplier 3.05) lowered the air permeability but did not affect the grab or tear strength in these fabrics.

Softness of Cotton Yarns as Affected by Fiber and Yarn Properties

Yarn softness is evaluated quantitatively as the percent increase in yarn width under a definite lateral force. Single-yarn softness decreases with twist and increases with yarn number and fiber maturity. With the above parameters constant, softness has no relation to fiber linear density. An equation is developed for estimating single-yarn softness from yarn diameter and twist and from fiber maturity. The softness of 2-ply yarns as related to the component single yarns is discussed. For modified cottons, in creased fiber friction apparently contributes to the decrease in yarn softness. An equation is developed to estimate the single-yarn diameter from yarn number and twist multiplier. The possibility that the diameter of the 2-ply yarn is related mathematically to the ply yarn twist multiplier and to the softness of the original unplied single yam is discussed.