Twist Multiplier Research Articles

Study on Fiber and Yarn Quality of Some Varieties and Egyptian Cotton Promising Crosses

This investigation was carried out during 2020 season on the laboratory at Cotton Technology Research Division, Cotton Research Institute, Agricultural Research Center, Giza, Egypt, to investigate the effect of two Egyptian cotton varieties (Giza 80 and Giza 94), and two promising cotton hybrids, i.e. hybrid cotton No. 1 [(G83xG80)xG89]Austrian and hybrid cotton No. 2 [(G89xK)xG86]xG94 on fiber and yarn technological properties under using the new technique of the ring spinning system at yarn count of 40's with 4.0 twist multiplier. The obvious results of this investigation can be summarized as follows: The differences between the studied Egyptian cotton genotypes in all fiber and yarn technological properties were significant, except micronaire value and fiber maturity were not significantly affected by cotton varieties under study during 2020 season. The promising hybrid 2 significantly recorded the highest upper half mean length (mm), fiber mean length (mm), fiber uniformity index (%), fiber bundle strength (g/tex) and lea count strength product vice versa, it gave lowest short fiber index (%), yarn evenness and No. of neps/100 m. Giza 94 cotton variety recorded maximum fiber stiffness (g/tex) and fiber brightness degree (Rd %), however it gave lowest fiber elongation percentage and fiber yellowness degree (+b). Maximum short fiber index (%), fiber yellowness degree (+b), yarn evenness and No. of neps/100 m as well as, the minimum upper half mean length (mm), fiber mean length (mm), fiber uniformity index (%), fiber bundle strength (g/tex), fiber stiffness (g/tex), fiber toughness (g/tex), fiber brightness degree (%) and lea count strength product which obtained from Giza 80 cotton variety. The fiber which obtained from promising hybrid 1 recorded greatest fiber elongation percentage and fiber toughness (g/tex).

Effects of Structural Modification and Some Parameters on Inverse Relaxation Behaviour of Polyvinyl Alcohol-Blended Polyester Yarn

Inverse relaxation is an undesirable phenomenon occurring with textile fibres or yarns which leads to certain fabric faults such as weft bars when fabric formation process gets interrupted due to unavoidable stoppages for indefinite times. In the present article, polyvinyl alcohol (PVA) fibre-blended polyester ring-spun yarns are prepared having different blend percentage and twist multiplier and their structure is modified by dissolution of PVA fibres. The inverse relaxation behaviour of polyvinyl alcohol fibre-blended polyester ring-spun yarns and modified yarns is assessed. Effects of various parameters such as level of extension, retraction, fineness of polyester fibre, proportion of PVA fibre and twist multiplier on inverse relaxation behaviour of the both parent and modified yarns are investigated by employing Box–Behnken design of experiments and response surface methodology.

Effect of yarn structure variables on comfort properties for cotton towels

The main purpose of this research is to study the effects of yarn structure variables as key factors influencing the comfort characteristics of cotton towel fabrics. Results of this work can help the producers or manufacturer to create desired quality towel fabric using optimum yarn parameters. The heaviest Grams per Square Meter (GSM) and the highest water vapor permeability were recorded by the Egyptian variety (Giza 90) while the maximum water absorption and air permeability were recorded by the Sudan variety (Acala). It is shown that the mean values of all comfort properties except air permeability decreased when the yarn count and twist multiplier increased. It is obvious that most interaction effects among the yarn parameters (cotton materials, yarn count and twist multiplier) were no significant for all towel comfort properties. It is found negatively and highly significant correlation coefficient between air permeability and each one of the other towel comfort properties. On the other hand, it is indicated that the heavier and thicker towel had more ability to water absorption and water vapor permeability. Also, there was positive and highly significant relation between water absorption and water vapor permeability. Results indicated that there were positively and highly significant associations between yarn hairiness and all towel comfort properties except air permeability. On the contrary, negatively and highly significant associations were obtained between yarn properties being number of neps, thin and thick places and evenness CV % from one side and all towel comfort properties except air permeability from the other side. It is clear that the yarn elongation and yarn tenacity had weak and ineffective effects on the towel comfort properties.

Effect of spinning factors on stress-strain curves in egyptian cotton

This investigation aimed to determine the effect of spinning system, yarn count and twist multiplier and their interactions on single yarn mechanical properties. Also, the Stress-Strain curves were plotted with the yield points and breaking points and their corresponding yarn properties (toughness, stiffness and Initial Young Modulus) were derived and calculated. As well as, the relative importance % of three spinning factors toward the single yarn mechanical properties was measured.Resultsrevealed that the main effects of spinning factors i.e. spinning system, yarn count and twist multiplier were generally significant or highly significant on all single yarn mechanical properties except stiffness and initial Young's modulus. Regarded the first and second order interaction effects, they were no significant for all single yarn mechanical properties indicating that each one of the three spinning factors reflected similar behavior under the other two factors. It is obtained that the compact and ring spinning systems produced yarns are markedly stronger, good elasticity and more durable than the yarns spun by open-end system. Result indicates that finer yarns are weaker and have lower extension at break than coarser yarns. It is obvious that yield strain, breaking extension, breaking tenacity and toughness significantly increased as a result of increasing the twist multiplier from 3.5 up to 4.5. Results exhibited that the spinning factors explained the most single yarn mechanical properties variation expressed as coefficient of determination (R2). The maximum relative importance % was obtained by yarn count followed by twist multiplier for yield strain, yield stress and breaking extension while the spinning system was the second important factor for breaking tenacity and toughness. On the other hand, it is appeared that the studied spinning variables accounted for least and ineffective part of the variation of stiffness and Initial Young's Modulus.

Predicting the fabric width of single jersey cotton knitted fabric using appropriate software

Prediction of any property of the material has attracted the attention of many scientists all over the world in order to produce better products. Information Technology (IT) field has many applications and plays dominant role in the production of various products in the industry. Knitted fabric should satisfy a number of requirements of consumer. Fabric width is a very important property which affects knitted fabric comfort properties. The deviation from the fabric width will either lead to more consumption of raw material or affect profit of the company. Hence, controlling the width of the fabric has an adverse effect on company’s profit and usage of raw materials. An investigation of the prediction of the width of the single jersey cotton knitted fabric in a fully relaxed state using Data mining technique in Rough set Computational based Priority Prediction Model (RCPPM) is reported. The inputs were yarn count, machine diameter, required GSM, machine gauge, actual yarn count, lea weight, lea strength, twist multiplier, loop length, course per cm, wales per cm, length shrinkage, width shrinkage, and fabric width. The real-time textile dataset consisted of 7,505 single jersey cotton knitted fabric samples. The results showed that the fabric width obtained by using aforesaid model was found to yield very accurate values and compared favourably with the measured ones. This study will lead to the production of the knitted fabric with better comfort and dimensional stability.

Determination of the optimum technological criteria under different spinning systems affecting the yarn hairiness

Yarn hairiness is reflected the amount of free fibers protruding from the spun yarn body towards the outer yarn surface. From a spinning point of view, studying this phenomenon is considered essential step because it influences the post spinning operation and the characteristics of the end textile structure. Many spinning factors are affecting the yarn hairiness.The main objective of this search is to examine the effect of yarn count and twist multiplier on yarn hairiness under six different spinning systems. Accordingly, three yarn counts (40's, 50's and 60's Ne) and three twist multipliers (4, 4.4 and 4.8) were applied. The used spun systems were carded, combed, carded compact, combed compact, jetring carded and jetring combed systems. Three-dimensional response surface graphs were used to easy and faster understand the results. Results indicated that the lowest hairy yarn was spun by jetring combed spinning system with significant differences compared to the other spinning systems. Jetring carded and combed compact ring spinning systems occupied the second order regarding the production of the least hairy yarns with significant differences than the others. Overall the used spun systems, it is indicated that the hairy yarns may be dramatically decreased with increasing yarn count to a certain extent and then slightly decreased while the hairiness was gradually decreased with increasing twist multiplier. However, the percentage of decrease % of hairy yarn with increasing yarn count was greater than that observed by increasing twist multiplier under all spun systems. Multiple regression analysis exhibited that yarn count and twist multiplier explained the most variation of hairiness expressed as high values of coefficient of determination (R2 %). Also, it is presented that the relative importance % of yarn count toward yarn hairiness was greater than that observed by twist multiplier overall applied spun systems.

Effect of low-quality and inexpensive cotton materials on yarn properties using rotor spinning system

The current search aimed to produce medium and coarse yarns using low-quality and inexpensive cotton materials under the rotor spinning at four yarn counts being 10.s, 16.s, 20.s and 24.s with 4.4 twist multiplier. The used cotton materials were the waste from spinning extra long-staple cotton such as combed wastes, Giza 80 lint grade fully good fair, Giza 90 lint grade fully good fair, Giza 80 lint grade good fair, Giza 90 lint grade good fair, imported china variety and carded wastes. The used cotton materials were prepared from the commercial cotton samples of season 2017. The studied yarn mechanical properties were yarn strength, yarn evenness C.V.%, number of neps, number of thin places and number of thick places. However, the average values of five fiber properties being fiber length 2.5 %, short fiber content %, coefficient of variation fiber C.V. %, fiber strength and micronaire reading were measured for all used cotton materials. Results showed significant differences among cotton materials and among yarn counts for all studied yarn properties. The effect of interaction between cotton materials and yarn counts was only significant for yarn strength and yarn evenness C.V. %.Generally, it is obvious that the mean values of yarn strength were in descending order considering cotton materials of combed wastes, Giza 95 lint grade fully good fair, Giza 90 lint grade fully good fair, Giza 95 lint grade good fair, Giza 90 lint grade good fair, china variety and carded wastes, respectively. On the contrary, the mean values of yarn evenness C.V. %, number of neps, number of thin places and number of thin places were in ascending order for the same aforementioned cotton materials. The mean values of yarn strength were gradually decreased when the yarn count was increased while the mean values of yarn evenness C.V. %, number of neps, number of thin places and number of thin places were gradually increased when the yarn count was increased.

Systematic investigation of twist generation and propagation in a modified ring spinning system

Twisting is an important process used to form a continuous yarn from short staple fibers and to determine the structure and properties of the resultant yarn. This paper systematically examines the yarn twisting process in a modified ring spinning process based on a theoretical model proposed recently. To reduce the number of experiments, response surface methodology (RSM) involving a central composite design (CCD) in three factors—twist multiplier, speed ratio and wrap angle—was successfully employed for the study and analysis. The significant terms of the models were studied, and it was discovered that the speed ratio and wrap angle are statistically significant for the responses of twist efficiency, propagation coefficients of twist trapping, and congestion. More importantly, linear relationships were found among the three responses.

Theoretical study of the effects on yarn strength in a modified ring spinning system

A modified ring spinning system using a dynamic twist-resistant device has been employed to produce yarn. The modified device blocks twist to propagate to the spinning triangle, which changes the distribution of twist in the spinning area and increases the height of the spinning triangle. In this paper, two kinds of yarn counts (30 and 40 Ne) are spun in the conventional and modified ring spinning with twist multipliers of 3.2, 3.6, and 4.0. The results show that the yarn spun by the modified ring spinning system possesses a higher strength compared with the conventional yarn except in the higher twist multiplier. The increase in yarn strength was theoretically analyzed according to the model of yarn strength. The yarn strength was calculated by considering the original fiber strain in the yarn and the fiber strain due to yarn strain. In the model, the fiber migration was considered and the fiber entanglement caused by fiber migration was ignored to simplify the calculation. Four potentially important parameters of the spinning triangle, the height of the spinning triangle, the migration coefficient, the inclination angle, and the spinning tension, were proposed and their individual and interaction effects on yarn strength were analyzed. The results demonstrate that yarn strength increased with the increase of height of the spinning triangle and the migration coefficient. The inclination angle and the spinning tension have a relatively small influence on yarn strength when the height of the spinning triangle is higher.

Processing of metallic fiber hybrid spun yarns for better electrical conductivity

ABSTRACTThis research was aimed at processing of metallic fiber hybrid spun yarns consisting of polyester/stainless steel and viscose/stainless steel staple fibers to achieve better electrical conductivity. Conventional ring spinning machine and ring twister machine were used to produce the single and plied yarns respectively. The linear electrical resistance of yarns was analyzed with reference to the three levels of twist multiplier (TM) for same yarn count, three levels of yarn fineness (Ne) at the same TM level, and number of plies for the same final yarn count. These results showed that by increasing twist, the electrical conductivity of yarn was increased. However, yarn fineness was in inverse relation with the electrical conductivity of yarns. The effect of yarn plying and twisting to produce the Ne 10s yarn was also found critical in governing the electrical properties. The electrical conductivity of viscose and stainless steel hybrid yarn was found more sensitive to increase with an increase in relative humidity contrary to that of polyester and stainless steel hybrid yarns. The findings of the study are significant to produce the hybrid spun conductive yarns for their potential applications in a variety of tailor-made functional, protective and smart textiles.

Effects of Process Parameters on Tensile and Recovery Behavior of Ring-Spun Cotton/Lycra Denim Yarn

Effects of yarn count, twist multiplier, stretch percentage and extension percentage on tensile and recovery behavior of cotton/lycra core-spun yarn had been investigated. Core-spun yarns were prepared in a modified ring frame. A 70 dtex lycra filament was inserted in core and sheath consisted of cotton fibers. It had been observed that yarn count, lycra stretch ratio, extension and twist multiplier had significant effect on tensile and recovery properties of the yarn. A 33 Box–Behnken response surface design was employed to investigate their influence on recovery behavior of the yarn. The immediate elastic recovery and delayed elastic recovery of the yarn were found to be increased with a decrease in stretch percentage. The immediate elastic recovery was observed to be increased with an increase in both yarn count and extension, whereas delayed elastic recovery was found to be increased with a decrease in extension. Total elastic recovery was found to be up to 67% and up to 45% in case of finer yarn (12 Ne) and coarser yarn (8 Ne), respectively.

Structure–property of DREF-3 friction spun yarn made using twisted staple fibrous core

ABSTRACTThis article discusses the structure–property relationship of DREF-3 friction spun cotton yarn in which the core is a single twisted cotton ring yarn and the sheath is made of the same cotton fibers. The structural changes in the single staple fiber yarn when subjected to DREF spinning have been studied by using tracer fibers. The single yarn physical properties, namely its count, twist multiplier and twist direction, and the proportion of the sheath fibers used during the spinning trials, were found to correlate with the final Dref yarn mechanical properties. It was observed that the direction of single yarn twist has the most significant effect; besides, the amount of twist multiplier in the single yarn and the proportion of sheath wrapping fibers largely determine the tensile properties of such core yarns. Since breaking tenacity and elongation of the DREF yarn are inversely related, it will be appropriate to compare them in terms of specific work of rupture.

Analyzing the effect of spinning process variables on blow room blended cotton melange yarn quality

PurposeThe use and importance of mélange yarn in apparel sector is increasing day by day. With the gradual increase in market share, achieving the desired quality level of mélange yarn remains a challenge for yarn manufacturing industry. The purpose of this paper is to investigate the effect of raw material (dyed fiber percentage in the mixing), important spinning process variable (yarn twist multiplier) and productivity (spindle rpm of ring frame) on properties of cotton mélange spun yarn.Design/methodology/approachBox and Behnken Design of experiment has been used to investigate the important yarn quality parameters like evenness, imperfection, hairiness, breaking strength and breaking elongation of blow room blended cotton mélange yarn. The quadratic regression model is used to derive the statistical inferences about sensitivity of the yarn quality parameters to the different process variables. The response surfaces are constructed for depicting the geometric representation of yarn quality parameters plotted as a function of process variables.FindingsThe study shows that shade depth and spindle speed have significant effects on the mélange yarn unevenness and imperfections. Mélange yarn strength and hairiness are significantly affected by shade depth and yarn twist multiplier (TM). Yarn elongation at break is only influenced by the spindle speed. A darker shade is responsible for higher yarn unevenness, imperfection, hairiness and lower yarn strength. A higher spindle speed is also liable for deterioration of yarn quality.Practical implicationsMany spinning industries are planning to convert their existing spindles from normal gray yarn production to mélange yarn manufacturing. The outcome of this study will lead to achieve better mélange yarn quality and productivity by the industry.Originality/valueResearch on mélange yarn is itself scant. This study is exclusively conducted to analyze the individual and interactive effect of various process parameters on the mélange yarn quality.

The Effect of Twist Multiplier, Elastane Percentage and Pick Density on Denim Quality

The Effect of Twist Multiplier, Elastane Percentage and Pick Density on Denim Quality

Analyzing the Effect of Spinning Process Variables on Draw Frame Blended Cotton Mélange Yarn Quality

An investigation has been made to study the effect of important spinning process variables namely shade depth, ring frame spindle speed and yarn twist multiplier (TM) on various yarn quality parameters like unevenness, strength, imperfection, elongation at break and hairiness index of draw frame blended cotton melange yarn. Three factors Box and Behnken design of experiment has been used to conduct the study. The quadratic regression model is used to device the statistical inferences about sensitivity of the yarn quality parameters to the different process variables. The response surfaces are constructed for depicting the geometric representation of yarn quality parameters plotted as a function of process variables. Analysis of the results show that yarn strength of draw frame blended cotton melange yarn is significantly affected by shade depth and TM. Yarn unevenness is affected by shade depth and ring frame spindle speed. Yarn imperfection level is mainly influenced by the shade depth and spindle speed. The shade depth and yarn TM have shown significant impact on yarn hairiness index.

Estimation of yarn strength based on critical slipping length and fiber length distribution

Yarn strength is composed of the total contributions made by all breaking and slipping fibers which are determined by critical slipping length lc. Though the definition of lc has been the focus of many research projects, it still remains unsolved. In this study, idealized assumptions were made on yarn structure, and lc was then estimated. At the same time, the actual contributions that breaking fibers and slipping fibers make to yarn strength were recalculated based on an idealized yarn structure, which was analyzed with the conditional probability method according to fiber length distribution. Then, yarn strength was computed by simulating random fiber arrangement in the yarn. It could be seen from calculated results that the critical slipping length declines as yarn twist multiplier increases. Meanwhile, as the twist multiplier increases, the calculated yarn strength rises to the highest point and then declines, which is in agreement with traditional spinning theory. Thus, the calculation of yarn strength based on critical slipping length could reflect the yarn breaking mechanism with a change in the yarn twist multiplier, and could be applied for further prediction of yarn strength.

Tensile and Elastic Performance of Cotton/Lycra Core Spun Denim Yarn

Various cotton/lycra core spun yarns are prepared in modified ring frame. The core of the yarn consists of a 70 dtex lycra filament and sheath consists of staple cotton fibers. The cotton/lycra core spun yarns are explored for the suitable application of stretch denim fabric. The tensile and elastic performance properties of the prepared stretch yarns are evaluated. The influence of various parameters viz. pre-load, linear density, stretch percentage, twist multiplier and applied load during tensile testing, on the properties of the stretch yarns are investigated by employing a full factorial design and statistical analysis.

Environmental Performance Evaluation of Polycarbonates Production Processes

The bursting strength, abrasion and pilling resistances of the single jersey and 1x1rib knitted fabrics are studied. The study was done as per American Society for Testing and Materials (ASTM D3786-01, D4966-98 and D4970) under controlled condition as per ASTM D1776- Practice for Conditioning Textiles for Testing. Three different twist levels such as 900turns/m, 1050turns/m and 1200turns/m with respective twist multipliers for each level such as 3.6, 4.2 and 4.8 are used in this study. 100% cotton fiber imported from India is used to produce carded ring spun yarn. In this study except twist multipliers (TM) the other yarn properties and knitting variables are controlled constantly as shown in the methodology of this research. The knitted fabrics such as single jersey produced from 900turns/m, 1050/m and 1200turns/m are named Sj1, Sj2 and Sj3 and rib1x1 produced from 900turns/m, 1050turns/m and 1200turns/m are named R1, R2 and R3 respectively.

Prediction of Blended Yarn Evenness and Tensile Properties by Using Artificial Neural Network and Multiple Linear Regression

Abstract The present research work was carried out to develop the prediction models for blended ring spun yarn evenness and tensile parameters using artificial neural networks (ANNs) and multiple linear regression (MLR). Polyester/cotton blend ratio, twist multiplier, back roller hardness and break draft ratio were used as input parameters to predict yarn evenness in terms of CVm% and yarn tensile properties in terms of tenacity and elongation. Feed forward neural networks with Bayesian regularisation support were successfully trained and tested using the available experimental data. The coefficients of determination of ANN and regression models indicate that there is a strong correlation between the measured and predicted yarn characteristics with an acceptable mean absolute error values. The comparative analysis of two modelling techniques shows that the ANNs perform better than the MLR models. The relative importance of input variables was determined using rank analysis through input saliency test on optimised ANN models and standardised coefficients of regression models. These models are suitable for yarn manufacturers and can be used within the investigated knowledge domain.

A novel method of yarn cross-sectional area calculation

Purpose This paper aims to study the yarn cross-section shape which is a very important yarn physical parameter and has a dominant effect on the physical structure of the yarn. Four factors affecting the yarn cross section, i.e. twist multiplier, Roving hank, spinning system and doubling technique, were investigated. Design/methodology/approach In past researches, the yarn cross-sectional area was calculated by considering any one yarn radius giving the approximate yarn cross-sectional area by assuming the yarn as a circular one. Findings In this study, a testing instrument is fabricated as shown in Plates 1 and 2 for yarn cross-section measurement and a novel method for calculating the correct yarn cross-sectional area of the yarn was developed. Originality/value In the past, no such studies have been conducted on the yarn cross-section studies because of the various limitations of the yarn cross-section measuring or testing instruments.