A modifiedring spinning system, wherein a kind of airflow twisting device is equipped for improving the twist propagation process of ring spinning system, has been used to spun three different yarns, namely 29.2tex (Ne20), 14.6tex (Ne40), and 9.7tex (Ne60). The properties of corresponding knittedfabric, including the thickness, weight per square meter, distorted angle, bursting strength, and permeability are determined. The results show that the residual torque of spunyarn is reduced with both appropriate anticlockwise and clockwise directions of airflow. It is found that compared to knittedfabricmadefrom conventional ring spinning system, the fabrics spun on modified spinning system show reduced thickness, weight per square meter and spirality angle; increased bursting strength; and improved permeability.
The present study is aimed at accessing the impact of elastane core liveliness on physical and mechanical properties of elastane-cotton core-spunyarnfabric. The yarn liveliness is altered by changing draw ratio on ring frame and thus the elastane core % in the yarn. The 4 samples of 30 s Ne elastane core-spun cotton yarn have been produced using 40 den elastane having 5, 7, 9 and 11% elastane core adjusted by using suitable draw ratio on ring frame. These elastane core-spun cotton yarns are used in weft direction to produce fabric sample. These fabric samples are tested for various physical and mechanical properties as per ASTM standards. The findings reveal that the yarn core liveliness has significant effect on various physical and mechanical properties of fabric.
The production of man-made fibre yarns on rotor machines has received increased attention. These yarns have not been well accepted as a substitute for ring-spun yarns. Rotor-spun yarns are inherently weaker 5than ring-spun yarns because of structural difference and the manufacturers are concerned about the weavability and fabric strength. Good results can obtained with plying of rotor yarn
confidence, that the difference between bending rigidity and bending modulus of these fabrics are meaningful in both warp and weft directions. Many factors that affect comfort in fabrics depend on the ability of the constituent yarns to withstand compressive deformation. Regardless of fiber type, spunyarn structure appears to provide superior resistance to compression in apparel fabrics. One of the most important features in the bending of woven fabrics is the bending resistance of the thread lying in the direction of bending. Another factor is the frictional resistance. In bending of fabrics, the fibers in a yarn pass through under pressure and intersection regions . Hence for bending, fibers must slip individually through each other. The relationship between fabric bending rigidity and yarn bending rigidity is highly complex. Yarn bending behavior is determined by the mechanical properties of constituent fibers and the structure of the yarn. The warp yarns used in 10 samples had the same characteristics and weave pattern. The same pattern was used in all fabrics, so the difference in bending parameters is due to weft yarn structure which affects the fabric structure and properties. In the sample fabricmadefrom hollow weft yarn, weft yarns have an empty space in the center. This empty space together with loose structure of the yarn could increase the fiber movement and slippage during bending. This leads to the freedom of movement of fibers in the internal structure of yarns. The diameter of hollow yarn is more than that of typical yarn but yarn contraction and deformation is higher under compressive stresses in a lateral direction due to the hollow structure. This means that, the collapse of fibers affects the bending behavior and has a dominant effect. Finally, in hollow yarn, the cross sectional shape is elliptical (Figure 1) and study on the distribution of fibers in the cross section of the yarn by microtomy shows that in hollow yarn the rate of ellipticity was 1.2-1.3. So, in hollow yarn the difference between minor and major axis of cross section is considerably higher. Ellipticity was calculated by measuring and dividing major axis of the hollow yarn cross section by its minor axis after taking a photo. This can explain why the bending rigidity of fabricmadefrom hollow weft yarn is less than that of fabricmadefrom typical
better abrasion resistance of yarns aids better running properties during knitting. While vortex spinning produces yarn of favorable properties at competitive cost, the selection of the fiber used to make the yarn is important. Being among the oldest regenerated cellulosic fibers, viscose fiber is more absorbent when compared to cotton. Therefore it can be used for the production of garments where absorption of perspiration from the human skin is paramount. Hydrophilic fibers like viscose can absorb liquids into the fiber structure thus preventing the spread of liquids, including sweat, along the fabrics. These liquids can be wicked away from the skin through the fabric to the outside where they evaporate, thereby keeping the body cool. Therefore a combination of viscose fiber, which is hydrophilic in nature, vortex spinning, which can be used to manufacture yarn of unique properties, and knitting, a fabric formation system which produces fabric with unique porosity and thickness properties, could produces fabrics with unique moisture transportation properties.
Results show that the fabric thermal comfort characteristics of fleece fabrics improve after raising process. However, fabric abrasion resistance deteriorates after raising process by 55%. Fabric thermal comfort characteristics are also influenced by backed yarn linear density, where they are improved when knittedfrom coarse counts. Furthermore, as backed yarn English count decreases, fabric weight per square meter increases, and the shrinkage, spirality, bursting strength and abrasion resistance improve. Finally, for fleece fabric, as backed yarn twist factor increases, spirality increases, and weight per square meter and abrasion resistance decrease. Also shrinkage rate improve. However, its influence on other fabricproperties is insignificant. Thus, the optimum settings for producing raised fleece knitted fabrics include the backed yarns with coarse diameter (approximately twice the ground English yarn count) and with a minimum twist factor. Therefore, it is suggested for the future work to compare between three-end fleece knitted fabrics propertiesmadefrom open-end and ringspun yarns as a backed yarns.
The blending of cotton fiber with polyester fiber is done to enhance drape properties, comfort ability, dye ability and many other properties of the fabric products [7,8]. In the cotton/polyester blends, polyester fiber plays an outstanding role in all areas of the life-saving medical textiles to the geo-textiles [9,10]. The advantages of polyester over other fibers are strength, luster and aesthetics properties [11,12]. The polyester fibers do not possess a high absorption of water and wick less water. In this research project, there is focus on the economic growth, quality of product and profitability range. It will focus on to set manufacturing process parameters so that yarn spinning industry earns more profit, changing market trends, customer requirement, product application and product properties on demand to maintain standard quality and productivity of yarn as per customer requirement. Due to high crisis, there are requirements to form recipes of different types of fibers in such ratios as final quality and profitable product can be made. This research was conducted to investigate the final qualitative and profitable product of the yarn via blending of PSL and Khalis polyesters, achieving the quality parameters and maximizing profitable range. Recipe of the KFL and PSL polyesters fibers in different ratios were made to achieve the required strength and quality characteristics of qualitative yarn. Due to improper control of recipe in blow room process by operator, we suggest the new model for the spinning process to run in an efficient way and mix fibers, which is required for a recipe that set for quality development and profitable product. By controlling manufacturing process with semi-automated devices this provides easiness to the operator to control manufacturing process in an efficient way, which produces the final quality product.
for yarn production by inducing some sort of modifications on ring spinning technology . The most accepted of them is the compact spinning system. Compact yarn is a revolution in spinning technology on that respect. Yarns produced by compact spinning have many advantages over traditional ringspun yarns. Over recent years, the system of compact spinning has constituted a rapidly developing technological trend in most countries. The present research was conducted to study the properties of compact spun and traditional ringspun yarns. The results show that almost all the properties of the compact yarns are better than that of traditional ringspun yarns.
ANN is a structure inspired from the human brain. ANN is very useful for modeling nonlinear problems and complex functions. ANN consists of three layers including input, hidden, and output layers. Neurons in each layer are connected by associated weights to other neurons in the next layer. The input data is received in input layer and the output is obtained in the output layer by a mathematical function through hidden layers . In ANN there are three operations including training, validation and testing sets. Training is used to train the ANN. Validation is useful when the network begins to overfit the data, and testing group is used to control the error during the training process . In this study for predicting mechanical and physical properties of compact-core yarns, a feed forward multilayer ANN model was used.
samples due to weathering is represented . Polypropylene composites were also studied by Shubhra et al. Degradation studies were carried out by accelerated and natural weathering. The mechanical properties were evaluated and it was found that glass fiber/PP composites degrade more rapidly compared to silk/PP composites . Yanagi et al. report an investigation of the deterioration mechanism of aged silk fabrics. The results indicate that silk decomposes first in the amorphous region with aging . The investigation carried out by Dierickx and Berghe  was focused on the change of tensile properties due to natural weathering. The results show that the effect of weathering is material dependent, and that ultraviolet stabilized materials show only a continuously slight decrease in tensile strength with exposure to time. The effects of simulated weathering on the tensile strength and tear strength of single-fiber and blended fabrics were the focus of investigation performed by Barnett and Slater . Their results show general similarity of behavior with individual variations, where molecular bonding explanations were suggested. Furthermore, four-modes of abrasion testing were used on fabrics and the results show that degradation of fabrics differ in each case . Efforts were also made to compare the degradative effects produced in cotton and other textile fibers by unfiltered light and natural weather exposure tests, where the sunlight is believed to be the chief degrading factor .
consequence, single-knit fabrics may experience permanent deformation. To improve the recovery performance of circular single-knit fabrics, it is now common practice to co-knit a small amount of spandex fiber or yarn with companion cotton yarn. As used herein, Lycra means a manufactured fiber in which the fiber forming substance is a long–chain synthetic polymer comprised of at least 85% of segmented polyurethane . The polyurethane is prepared from a polyether glycol and chain extender and then melt-spun, dry-spun or wet-spun to form the spandex fibers. There are many different counts and types of spandex on the market. The main ones are yarns that are used on circular knitting machines together with other yarns. For jersey knit constructions in circular knitting machines, the process of co-knitting spandex is called "plating." When the cotton yarn and the spandex yarn are knitted parallel or side-by-side in every course, with the spandex yarn always kept on one side of the cotton yarn, the method is classified as “full plating.” When the Lycra is placed in alternating courses, the method is classified as “half plating.” Feeding of the Lycra yarn to knitting machine with a rate less than the required stitch length of cotton yarn results in yarn extension which in turn generates tension, and as the knitted loops leave the needles the spacing of courses and wales decrease and the fabric shrinks in both directions thus affecting the properties of knittedfabric.. The aim of this research was to study the effect of Lycra extension percent on the properties of the plain jersey fabrics by quantitative assessment in order to predict the optimal lycra extension percent with respect to fabric required quality.
In this study effect of fabric softeners that are used during bleaching and dyeing process to improve fabric handle, high elastic resilience and sewing performance on burning behaviour of knittedfabric was investigated. After comprehensive literature survey it was seen that no published data exist with regard to the effect of softening finishes on the burning behavior of knitting fabrics. However, softening finishes will add a fuel source via the softening agent’s flammability characteristics. Fire hazards due to clothing depend on various factors such as fiber type, fabric construction, chemical finishes and oxygen concentration. For this aim, in this study, cationic, amphoteric and non-ionic based softeners were chosen and they were applied to cotton knitted fabrics at the five different concentrations. Burning behaviour of the all fabrics was evaluated by using BS 5438 vertical flammability test method due to its results are very similar to real fabric burning behaviour and it is more responsive than the other test methods. The relationship between flame propagation rate and concentration of the softeners were tried to define. Experimental results were evaluated according to Polynomial Regression Analysis by using SPSS statistical programme and how and at which level softener’s concentrations affect knitted fabric’s burning behaviour was defined. Generally using fabric softeners, at each concentration levels considerably caused the fabric’s flammability to increase.
The effect of compact yarn on downstream process such as knitting has been studied. Weft knitted fabrics such as single jersey, single lacoste, double lacoste, honeycomb, popcorn, rib and interlock fabrics have been produced from regular and compact cotton spun yarns. These fabrics after dyeing and starfish relaxation treatment are investigated by Kawabata evaluation system for their low-stress mechanical properties. The results show that in a few cases the differences between regular fabricproperties and the compact fabricproperties are quite significant, while marginal in other cases. However, the surface roughness values show some interesting features.
In conventional ring spinning, the zone between the nip line of the pair of delivery rollers and the twisted end of the yarn is called the “spinning triangle” which represents the critical weak spot of this process. The fibre assembly contains no twist in this zone. The edge fibers lead to the familiar problem of yarn hairiness [5-7]. But in compact spinning, the fibres which have left the drafting system are guided via the perforated drums over the openings of the suction slots. Following the air flow, the fibers move sideways and are consequently condensed. This condensing has such a favorable effect on the ratio of the width of the condensed fibre to yarn diameter that the spinning triangle is nearly eliminated (figure 1). Almost all the fibres are incorporated into the yarn structure under the same tension when spinning is done without spinning triangle. As the twist insertion takes place very close to the nip line, short fibers can take up tension. Therefore, the yarn strength is increased as more fibres contribute to the yarn structure. [5, 6, 8-10]. The fly and dust reduction is occurred as an effect of condensation. The cleaning requirement is reduced compare to conventional ring spinning frames.
This study facilitates an effective design and development of various high stretch com- pression products by analyzing fabric size, stretch properties, and clothing pressure for various knit structures. Four types of fabrics were knitted with polyester SCY (Single Covered Yarn). Then fabric size including weight and thickness, stretch properties (stretch, elastic recovery), and clothing pressure were then measured, to analyze their interrelation. A comparison of fabric size indicated that yarn floating caused reduc- tion in both course and wale-wise specimens; in addition, yarn overlapping caused a release in course-wise and shrinkage in wale–wise due to tuck. The high density caused by shrinkage in the course-wise due to yarn floating rather than overlapping influenced the weight and thickness of knitted fabrics. Yarn floating reduced course- wise elasticity and increased wale-wise elasticity in the fabric stretch test; however, yarn overlapping reduced elasticity in both directions. The elastic recovery analysis indicated that the recovery value gap among four specimens decreased over time. In compari- son clothing pressure, ‘plain-float’ fabric showed higher clothing pressure than ‘plain’, while the pressure value of ‘plain-tuck’ was similar to ‘plain’. Dimensional change in course-wise had a greater effect on clothing pressure than in wale-wise in the correla- tion among fabric size, stretch properties and clothing pressure. Weight and thickness change exerted a strong influence on clothing pressure which vertically presses down the body. The clothing pressure value of knitted specimen having a lower stretch ratio was higher in course-wise.
This research investigates the effect of fiber, yarn and fabric variables on the bagging behavior of single jersey weft knitted fabrics interpreted in terms of bagging fatigue percentage. In order to estimate the optimum process conditions and to examine the individual effects of each controllable factor on a particular response, Taguchi’s experimental design was used. The controllable factors considered in this research are blending ratio, yarn twist and count, fabric structure and fabric density. The findings show that fabric structure has the largest effect on the fabric bagging. Factor yarn twist is second and is followed by fabric density, blend ratio and yarn count. The optimum conditions to achieve the least bagging fatigue ratio were determined.
directions and uniaxial tensile load was applied to identify the shear angle (6- 9). On the other hand, it was reported that a fixture was developed in the bias-extension method, called the picture-frame (or trellis-frame) to conduct the shear test on a square fabric sample where the shear lock limit was reached (10). There were inconsistencies between the fabricproperties measured in simple shear and by bias-extension due to factors including the specimen geometry, thread properties and variation in normal stress during bias-extension (11). Fabric shear behavior was found to depend on applied tension, specimen size and fabric set. It was identified that buckling due to specimen size affected the fabric’s shear rigidity (12-14). For a wide range of conventional fabrics, the shear limit was defined by the side-by-side contact of one set of yarns. By using the picture-frame shear test method, a microstructural analysis was carried out in high modulus fiber based fabrics to investigate shear locking on the basis of a geometrical approach and the maximum packing fiber fraction (15). An edge-clamped fabric holding fixture was developed (16). However, transverse tension applied to the fabric through a spring-mounted sliding edge clamp prevented the measurement of the fabric’s simple shear. The aim of this study was to determine the in- plane shear properties of polyester ribs fabric by the pull-out method and to interpret the shear behavior of this fabric based on the generated data and develop analytical model.
Abstract - One way to improve the properties of staple yarns is to employ core–compact yarn spinning system. This type of yarn is used in a wide range of applications and up to now many researchers have studied its production process and properties. However, there is a lack of researches regarding the optimization of the properties of rotorcraft compact spinning (RoCos) core-spun yarns based on the spinning parameters. Therefore, in this paper, the influence of some spinning parameters including the pre-tension of filament, yarn count and type of sheath fiber on the properties of RoCos core-spun yarns was investigated. To achieve the goals of this research, the physical and mechanical properties of RoCos core-spun yarns including the tenacity, hairiness and abrasion resistance were measured, and then modeled by artificial neural network (ANN). Finally, to optimize all measured properties at the same time the ANN models and non-dominated sorting genetic algorithm (NSGAII) method were applied as a hybrid model. The results showed that the presented method could be successfully used to determine the spinning parameters to produce RoCos yarns with desired properties. The optimized values of hairiness, tenacity and abrasion resistance for an ideal yarn were observed at yarn count of 41.5 tex, filament pre-tension of 125 g and for sheath fiber of viscous/polyester.
In the Solospun rollers, the slots divide the drafted fibre strand into a number of sub-strands. In this spinning method, the width of the main twist triangle is the same as conventional ring spinning system. To prevent the end of fibres from escaping from the main strand body, a diagonally slotted roller (DSR) was designed with various slot angles to positively lead the end of fibres in two sides of the twist triangle to the yarn body and reduce the protrusion of the fibres from the body of the yarn. The key element of the newly developed spinning system is a pair of diagonally slotted rollers fixed on the conventional ring spinning frame. Unlike the Solo roller, the ‘slots’ in the DSR roller are not in parallel with the strand and runs with an angle to the strand which is called slot angle. The slots are symmetrically made up from two edges toward the roller centre to provide a convergent path for the fibres in the strand at the twist triangle. DSR rollers have multi-slot surface to lead fibres into the yarn end. This is a big difference from compact spinning with inspiratory groove which compacts fibres by airflow and single slot of the inspiratory groove 15 . In DSR roller, the slots
Although this thesis is about 2 spinning methods, we cannot draw conclusions based on yarn performance alone. It is necessary to convert these yarns in to fabrics and see how the end product performs with each type of spinning method used. After the yarns were tested, the remaining yarns were knitted on the FAK – Fiber Analysis Knitter. This is a circular single jersey knitting machine with a single feed and is used specially for laboratory purposes. The diameter of this circular fabric is approx. 3 inches, ideal for analyzing various aspects of the material. The needle density is 28 needles/inch and the machine was at a speed of 60 yd/min. Figure 3.4 shows the circular dial of the FAK and the fabric being knitted.