Number Of Yarns Research Articles

PERBAIKAN INSTRUKSI KERJA PATROLI MESIN TENUN SHUTTLE UNTUK PENINGKATAN EFISIENSI PRODUKSI

In general, the weaving manufacturing process at PT XYZ still has low productivity (79%), low efficiency (75%), and low product quality (grade C-). In fact, the company has implemented comprehensive quality control (on materials, processes and products) in the form of patrol inspection work instructions for shuttle loom machines. This research aims to improve or update existing work instructions so that they meet the rules of work instructions that are clear, detailed, easily accessible and comprehensive. Improvements to work instructions are chosen among a variety of other causes because the variables of work instructions and the people who carry them out are relatively easier to do and do not take long time. The selected sample includes 6 types of weaving machines in the production period from January to July 2024. The construction of woven fabrics that are the object of research is the manufacture of woven fabrics from cotton warp yarn and weft yarn with yarn number 40, end per inch 94, pick per inch 70, 50 inch fabric width, plain woven type and 100000 meter fabric length.This production batch needs 36 weaving machine shuttle-type for 49 days. After the work instructions were corrected and the operator was given training to be consistent and correct in carrying out work instructions, there was a change in the quality of weaving production at PT XYZ. The productivity value increased to 81%, the efficiency value increased to 76% and the product grade became C+ grade.

Mechanical Behaviour of Green Epoxy Composites Reinforced with Sheep and Dog Wool from Serra Da Estrela.

Environmental awareness has led industries and consumers to replace products derived from oil resources with products derived from natural sources. In the case of the composite materials industry, the replacement of synthetic fibres with natural fibres has increased in recent years. To study the influence that different types of natural fibres and different textile manufacturing techniques have on the mechanical properties of composites, bio-based epoxy matrix composites reinforced with different natural animal fibres were produced, some reinforced with sheep's wool and others with dog wool, which were later subjected to bending and tensile tests. From the authors' knowledge, there are few studies of composites produced with animal fibres, and even fewer with dog hair. The textile structures used as reinforcement were created using crochet, knitting, and weaving techniques. Prior to the composites production, the fibres were characterized by X-ray Diffraction (X-RD), and the yarns produced from these fibres were subjected to tensile tests. The results obtained suggest that the number of yarns and the diameter of the needles used during the production of the reinforcement have a significant impact on the mechanical properties of the composites. The green epoxy resin composites reinforced with sheep's wool exhibit higher values of flexural strength, tensile strength, and Young's modulus than those reinforced with dog wool, with average increases of 36.97%, 45.16%, and 72.99%, respectively. It was also possible to verify that the composites reinforced with woven fabrics and crocheted fabrics exhibit the highest values of tensile strength, flexural strength, and Young's modulus. Additionally, the composites reinforced with woven fabrics exhibit the highest values of deformation at first failure/break and toughness.

Viscoelastic behavior of warp-knitted spacer fabrics in iterative compression and decompression

In this study the viscoelastic behavior of warp-knitted spacer fabrics was investigated for compressional deformation. The fabric specimens were tested via loading and unloading time intervals under predetermined conditions. Following the upside tests, specimens were relaxed for 24 h to examine the recovery prior to completing the downside tests. The data obtained from the compression and decompression cycles were examined for stress relaxation and creep through stress–time plots. From the results it was observed that, despite the non-homogeneous structure of the spacer fabric, the specimens demonstrated exponentially changing behavior within the given time intervals. Since the response of fabrics to compression and decompression cycles can be expressed as a function of time, a mathematical approach was expressed in accordance with the time-dependent behavior of the fabrics regarding the monofilaments as bent beams. The responses of the fabrics to the experimental set up conditions were evaluated to determine the potential usage performances of the fabrics. Fabric thickness, number of monofilament yarns in the structure, and thickness of the monofilaments had the major effects on the performance of the fabrics. Future research could consider modeling studies to predict usage performance, and tailoring the fabrics before production.

A polyester- stainless steel based smart wristband sensor for skin temperature monitoring

This study presents the development and characterization of a novel textile-based wristband sensor for continuous temperature monitoring. The sensor, woven with a blend of polyester-stainless steel and polyester-cotton yarns, exhibited high sensitivity (0.0315/°C) and a rapid response time (∼35 sec). Stainless steel was selected for its excellent electrical conductivity and biocompatibility, crucial for accurate and safe skin contact applications, while polyester and cotton contribute its lightweight, breathable, and durable properties, ensuring prolonged comfort and wearability. Through systematic testing and optimization, the sensor’s sensitivity was fine-tuned by adjusting the number and length of conductive yarns. The study also introduced a theoretical resistance equivalent model, comparing its theoretical sensitivity with experimental findings. The sensor, lightweight and cost-effective, proved comfortable during 8–10 h of continuous wear. This study addresses challenges faced by existing textile temperature sensors and offers a reliable alternative with high linearity, repeatability, and suitability for individuals with sensitive skin.

Тарау жылдамдығының иірім жіптің сапалық көрсеткіштеріне әсері

In spinning production, the carding process has a great influence on the sliver’s quality, as well as the resulting yarn’s quality properties. This research work was carried out to substantiate the spinning yarn’s quality by changing the carding release speed. Changes in the yarn’s quality properties obtained at different carding speeds were analyzed using laboratory equipment Uster® system. The study’s main aim is to determine the optimal carding speed required to obtain low linear density yarn. Yarn number Ne 40/1 (14.5 tex) was obtained on a Zinser® ring spinning machine As a result of the study, it was found that when measuring the effect of spreading release speed on yarn inhomogeneity with increasing release speed from 180 m/min to 210 m/min with lower value of yarn inhomogeneity, with increasing spreading release speed from 180 to 210 m/min there is a continuous increase in yarn defects in spinning yarn. In the study, with the increase in release drum speed, the spinning yarn strength decreased from 16.8 cN/tex to 16.0 cN/tex. There was an increase in discharge speed from 180 to 210 m/min from 4.2% to 4.8% with low yarn pile. It was found that yarn elongation decreased from 5.42% to 5.25% due to increase in distributed release speed.

Optimising fundamental knitting parameters for wearable triboelectric nanogenerators

During the past decade, Triboelectric Nanogenerators (TENG) have demonstrated their potential as an energy harvesting and self-powered sensing technology for future wearable applications. Among various TENG architectures, knitted textile TENGs have become increasingly popular in recent times, as they provide advantages such as high electrical outputs, very good mechanical properties and excellent wearability. However, there is still a lack of understanding on how to engineer the knitting parameters to maximize the electrical output generation of knitted textile TENGs. Herein, for the first time, we bridge this gap by mapping the relationship between basic knit parameters and the fundamental TENG parameters which govern their electrical outputs. In this work, the loop length, yarn count, number of yarns per loop and the loop structure of a knitted textile TENG are empirically varied and its impact on the charge, current and voltage outputs is studied. The observed output trends are then analysed in-depth using the distance-dependent electric field theory, thus, explaining the root causes of the observed output trends. Consequently, several new strategies on the design and optimisation of more efficient knitted textile TENGs are uncovered. Further, the impact of these optimisation strategies on the wearable properties of the knitted textile TENGs is studied, paving the way for practically applicable textile TENG designs with balanced electrical output generation and long-term wearability.

Mechanical strength changes of combustible municipal solid waste components during their early pyrolysis stage and mechanism analysis.

Implementation of municipal solid waste (MSW) source segregation leads to a more convenient recycle of combustible MSW components. Textiles, plastics and papers are commonly available combustible components in MSW. Their shredding is conducive to resources recovery. But these components usually have high tensile strengths and are difficult to shred. To understand their mechanical strength changes in their early pyrolysis stage will help to address this problem. In this study, a universal electronic testing machine was used to determine the breaking strengths of the materials including cotton towel, polyethylene glycol terephthalate (PET), ivory board (IB), kraft paper (KP) and wool scarf in the temperature range of 30-250°C under N2 atmosphere, and the mechanisms of their strength changes were explored. The reaction force field molecular dynamics (ReaxFF-MD) simulation was used to explain the decomposition behaviours of different sugar groups of hemicellulose in cotton and paper and the change of van der Waals energy of wool during their early pyrolysis stages. The results showed that breaking strengths of all the combustible MSW components reduced as the temperature increased. The breaking strength of PET was found to have the highest descent rate with increasing temperature, then the descent rates of wool and cotton came as the second and third, respectively. Compared with cotton, the breaking strengths of KP and IB decreased more slowly. As the temperature increased, the breaking strength of cotton reduced mainly due to the decomposition of the glucuronic acid in hemicellulose, and the reduction was characterized by CO2 release. The breaking strength reduction of PET was caused by its molecular chain being relaxed. The breaking strength reduction of wool was firstly caused by the decrease in the van der Waals energy between its molecules, and then caused by molecular chain breaking. In addition, in order to understand the influence of material size on the breaking strength change during thermal treatment, the breaking strengths of cotton yarn bundles were correlated with their yarn number and temperature. This study lays the foundation for understanding changes in mechanical strengths of combustible MSW components during their early pyrolysis stage.

Call your Mothers! Sámi Culture-Based Curriculum Development Based on Mathematics Teachers, Students and Mothers in Joint Research Actions

This paper describes the collaboration between home and school during the planning of a mathematics teaching experiment involving ruvden, a Sámi braiding procedure. The experiment was conducted in a Sámi lower secondary school. In Sámi schools, Sámi language and culture shall constitute the basis for the teaching, but no cultural implementation usually takes place in the mathematics teaching. The teachers’ investigations of ruvden took place in collaboration with researchers and students during workshops, meetings and math days. The participants investigated the braiding procedure with different numbers of yarns; during one workshop, two girls’ mothers were invited to participate. The contributions of these new participants opened up for research questions with a focus on home-and-school cooperation. The first research question is: How did the mothers experience their involvement in the development of the Sámi culture-based teaching experiment? Analyses of that question prepared for another research question: How may home-and-school collaboration contribute to culture-based curriculum development? The mothers experienced their involvement positive, and the home-and-school cooperation had even implications for the content of the teaching experiment. The home-and-school collaboration took part on the basis of the perspective of shared responsibilities.

Flexible Puncture-Resistant Composites for Antistabbing Applications: Silica and Silicon Carbide Nanoparticle-/TPU-Coated Aramid Fabrics.

In harsh environments, it is crucial to design personal protective materials that possess both puncture/cut resistance and chemical resistance. In order to fulfill these requirements, this study introduces an innovative approach that combines hydrophobically modified rigid nanoparticles with thermoplastic polyurethane elastomers. These materials are then laminated with high-performance aramid fabrics through a scraping process, resulting in a multifunctional composite with puncture/cut resistance, superhydrophobicity, self-cleaning properties, and acid/alkali resistance. The quasi-static puncture tests conducted reveal the remarkable performance of the composite. The maximum spike puncture resistance reaches 267.62 N, which is 17.14 times higher than that of the pure fabric (15.61 N). Similarly, the maximum knife puncture resistance reaches 115.02 N, exhibiting a 5.01 times increase compared to that of the pure aramid fabric (22.97 N). Furthermore, the results obtained from the yarn pull-out, fabric burst strength, and tearing experiments demonstrate that the incorporation of rigid nanoparticles significantly enhances the friction between the yarns, enabling a greater number of yarns to participate in the dissipation of impact energy. As a result, the puncture resistance of the fabric is greatly improved. Significantly, the composite exhibits sustained superhydrophobicity even after exposure to harsh chemicals such as concentrated sulfuric acid and sodium hydroxide as well as undergoing cyclic mechanical wear. These findings highlight the composite's exceptional durability and resistance to corrosion. Overall, this study offers insights and methods for the development of multifunctional flexible puncture-resistant equipment for individuals.

Yarn level finite element method simulation for bending over sheaves of braided ropes

The complex problem of ropes (cyclic) bending over sheaves (CBOS) is considered in this article. Ropes that are used to manoeuvre and regulate sails undergo a variety of dynamic stresses which are crucial yet difficult to determine, due to the complexity of the multi-scaled braiding structure of ropes. A full dynamic Finite Element Method (FEM) simulation of a braided rope bending over a sheave is conducted with the commercial software Abaqus/Explicit, as it can capture the complex processes occurring inside the rope to high accuracy. A theoretical deduction is performed to determine the yarn paths in a 3D braided structure. Relative movement between braided yarns (including the interlacing point) are better assessed at yarn level through 3D element types instead of the traditional beam elements, as they allow to obtain an estimation of yarn-yarn displacement. Parametric studies are conducted to better understand the factors that affect the yarn sliding. The ratio between the diameter of the sheave and the rope, and the braiding angle, are found to be crucial for the relative movement, while the number of yarns and their diameters have little influence. The successful simulation process demonstrates the feasibility of modelling and analysing the complex interaction occurring in braided structures under specific boundary conditions. The calculated estimated displacement can contribute to further investigations such as the friction and heat generation problem in braided ropes. Simulation with this method can provide alternatives in predicting lifespan of braided products that cannot be easily inspected.

Physical and Mechanical Properties of Cotton/Polyester Based Fibers for Shoe Uppers and Lining Products

Abstract The purpose of the study was to evaluate the physical and mechanical properties of various textile materials based on polyester and cotton for shoe uppers and lining. For that purpose, the influence of the ratio of a mixture of cotton and polyester fibers on the quality of the fabric was investigated. As a result, fabrics with the same composition but different yarn numbers differed from each other in specified properties. With an increase in the content of polyester, all specified properties increase except for vapor permeability, which makes it possible to correctly select the composition of fabrics for shoes.

A novel model for predicting tenacity and unevenness of ring-spun yarn: a special case in textile engineering

This study aimed to model the unevenness and tenacity of ring-spun yarn in a special case in textile engineering using response surface methodology. Yarn number and front roll speed were input variables, while yarn tenacity and unevenness were response/output variables. This study showed that the response surface methodology (RSM) could predict the yarn’s tenacity and unevenness with the yarn coefficient of determination (R2) values of 0.99 and 0.98 and with the error sum of square (SS residual) values 0.00187 and 0.003215, respectively. We also found that an artificial neural network (ANN) could predict the yarn's tenacity and unevenness with the yarn coefficient of determination (R2) values of 0.51 and 0.63 and with the error sum of square (SS residual) values 1.48 and 0.856, respectively. It was concluded that the response surface methodology (RSM) and artificial neural network (ANN) could predict the yarn's tenacity and unevenness. Response surface methodology (RSM) predicts yarn characteristics better than ANN with MIMO (multiple inputs, multiple outputs) modeling. The novelty of this study is that we used RSM and ANN for the first time to obtain the tenacity and unevenness of ring-spun yarn accurately. A simpler approach was employed in this study for predicting tenacity and unevenness using RSM and ANN; however, future research holds the potential for incorporating advanced mathematical models to enhance the prediction. This research suggests that RSM and ANN can be applied to predicting the tenacity and unevenness of ring-spun yarn. The scientific application of this research is that the investigation will benefit practitioners in the textile industry to optimize yarn parameters by ring spinning machines.

Comparative Geometrical Analysis of In Situ Mechanical Performance of 2-D Woven In-Plane Auxetic Structures

Abstract Recently, the production of auxetic textiles using conventional yarns and equipment has captured the attention of researchers. Yet only uni-stretch 2-D woven auxetic structures and auxetic knitted textiles have been produced using conventional yarns. This paper reports a comparative analysis of auxetic and mechanical performance (tensile strength, tear strength, and stretch and growth %) performance of auxetic foldable and auxetic honeycomb (AHC) structures using common elastic and nonelastic yarns and conventional weaving technologies. For this purpose, five different auxetic weave designs including α-vertical pointed twill (S1), β-vertical pointed twill (S2), α-horizontal pointed twill (S3), β-horizontal pointed twill (S4), and honeycomb structure (S5) were selected, and their corresponding woven fabrics were developed with equal thread density at the weaving stage. Auxeticity of woven structures was measured in both the warp and weft directions. The results showed that when the developed fabrics were stretched along the warp and weft directions, the foldable geometry showed −1 and −0.07 maximum negative Poisson’s ratio (NPR), respectively. Although the AHC structure showed maximum NPR −0.94 and −0.21 along warp and weft directions, respectively. AHC showed better mechanical performance as compared with foldable geometry and has higher dimensional stability. AHC structure showed the highest tensile strength as compared with the others. S3, S4, and S5 remained untorn along the warp direction because these have longer float lengths that produce a bunch having a greater number of yarns, whereas S1 and S2 showed tear strength of 47 and 43.2 N, respectively. In the weft direction, only S1 remained untorn, whereas the other four samples showed the tear strength value.

X-ray microtomography analysis of the damage mechanisms in 3D circular braided carbon fiber/epoxy resin composite tubes under axial impact compression

The dynamic behavior of three-dimensional (3D) circular braided composite tubes with different braided parameters was experimentally investigated subjected to axial impact compression using a Split Hopkinson Pressure Bar (SHPB). The damage characterization of the post-impacted tubes was examined using scanning electron microscope (SEM) and X-ray micro-computed tomography (micro-CT). The influence of braided parameters and strain rate, including braided angle, the number of braided layer and axial yarn, on the dynamic mechanical properties, progressive crush characteristics and failure mechanism of 3D braided composite tubes was analyzed in detail. It was found that the smaller braided angle and the larger numbers of braided layers contributed to better axial dynamic properties. The compressive strength, stiffness and specific energy absorption (SEA) of 3D five direction (3D5D) tubes with axial yarn were larger than those of 3D four direction (3D4D) tubes without axial yarn. Meanwhile, the dynamic mechanical response and damage patterns of braided tubes exhibited significant strain rate effects. The impact compression failure mechanisms of braided tubes were mainly fiber tows crushing, fiber breakage, fiber buckling, shear fracture, resin cracking, interfacial cracks, fiber-matrix debonding, etc.

An experimental study for chemical characterization of artificial anterior cruciate ligament with coated chitosan as biomaterial

Abstract The importance and aim of this experimental study is that raw artificial anterior cruciate ligament samples were produced with various 3-D braiding constructions with various technical yarns using the 3-D braiding method. Later, it is aimed to determine the chemical bond changes between raw samples with ethylene oxide (EtO) sterilization and bio-chemical finishing samples by applying padding process and EtO sterilization processes for all samples with 3-D braiding structures, due to the cross-linking of biocompatible chitosan (CHI) with biological cross-linker glutaraldehyde (GA). The importance of this experimental study is that it is the first experimental chemical analysis in this field in the world scientific study. Padding and EtO sterilization processes were applied on all samples and compared to various technical yarns with 3-D braiding structures thanks to biocompatible CHI. Chemical analysis was interpreted for all samples. It was determined that the applied temperature, concentration, pH, yarn types, characteristic bonds in the chemical structure of the technical yarns, applied bio-chemical finishing process and EtO sterilization had effect on the formation, shifting and breaking of chemical bonds. It was determined that the yarn number, braiding geometry, braiding angle (°) and braid construction had no effect on the formation or shifting of chemical bonds. New bonds were formed thanks to CHI and GA due to their extremely reactive between 5 and 5.5 pH. They reacted quickly with Schiff base bond in all samples. CHI was ionized in all samples. It was determined that new bonds were formed in UHMWPE, PPD-T and HT PET structures. The most common bond formations were HT PET > PPD-T > UHMWPE. The reasons for these chemical structure changes in all samples depended on their chemical structures, bond types, molecular weights, reactivities, ease and speed of diffusions, crystallinities of technical yarns and all chemicals used. In order to increase the formation of new chemical bonds the pH should be between 5 and 5.5. GA concentration should be a minimum of 25% or higher. The dissolution time of CHI should be minimum 3 h or more. The dissolution process temperature of CHI should be minimum of 70°C or higher. The absorption, adsorption and chelation properties of CHI on all samples will also be evident successfully as in this experimental chemical study.

The design of experiments in the field of technical textiles as an educational module

Mastering software knowledge for the design of textile fabrics is especially important for students of higher education and offers substantial competitive advantages within the world of work. The Erasmus+ project OptimTex has prepared up-to-date educational materials as a response to the digitization requirements of Industry 4.0 in the textile field. This paper presents the content of an e-learning module conceived by the coordinator of the Erasmus+ OptimTex project. The module addresses the design of experiments in the field of technical textiles for electromagnetic shielding, with the following technical aspects: two input parameters, the weft fabric density (number of yarns per 10 cm) and the thickness of the plasma-coated metallic (copper) layer on both sides of the fabric (nanometre) and one result variable, the electromagnetic shielding effectiveness of the fabrics (dB) at 100 MHz. A Box-Wilson central composite design was applied to optimize shielding effectiveness related to both input parameters. Software such as Excel, MATLAB and MODDE was applied to compute and cross-check the response surface modelling.

Weaving with a new warp yarn break detection system using contact linear image sensors instead of drop wires

A thin metal plate called a drop wire is placed on warp yarns during a weaving process in order to stop the loom in case of a broken warp yarn and to fix it. Drop wires are placed on each warp yarn to ensure the flow of warp yarns at a certain tension level and to stop the loom when a warp yarn is broken. In some cases, the drop wire may not fall due to dirtiness or abrasion of the drop wire and the weaving process continues with a broken warp yarn which is an unwanted situation. In this study, an alternative method to detect broken warp yarn is proposed based on contact image sensor. Therefore the need for drop wires is eliminated. The contact image sensor is not at full scale of the weaving machine, it can only acquire a linear image only a small portion of the total warp yarns, therefore a carrier module is implemented on the machine to carry the sensor and cover all the warp yarns. A complete image is then formed at the end of each cycle, and the total number of warp yarns is evaluated. If this value is less than the expected number of warp yarns, a broken warp yarn is detected, and the system generates an alarm. The system is implemented on an industrial scale weaving machine and the warp yarns are detected with 99% performance.

Effect of Yarn Physical Properties on Fiber Migration and Packing Density of Cotton/Acrylic Blended Yarns

In the scope of the study, the effect of fiber blending ratio, yarn count and twist coefficient on fiber migration, packing density and diameter of the cotton/acrylic blended yarns were investigated. The yarn samples with 75-25%, %50-50%, 40-60% cotton-acrylic blending ratios were produced with three different yarn numbers; 20/1 Ne, 24/1 Ne, 30/1 Ne and three twist coefficients; 3.5 α, 4 α, 4.5 α. Thus, totally 27 yarn samples were obtained. The yarn cross-sectional samples were sliced with microtome. The image frames of yarn cross-sections were acquired via digital microscope. The yarn packing density was calculated by using image processing algorithm and the fiber migration was determined via cross-section images. The results were evaluated statistically.

Effects of volume fraction and surface coating of textile yarns on the tensile performance of AR-glass textile reinforced concrete

This study investigates the effects of volume fraction and epoxy coating of textile yarns on the failure morphologies and tensile properties of alkali-resistant glass textile reinforced concrete (ARG-TRC). The quasi-static tensile tests were first carried out on the single yarn and fiber strips with different numbers of warp and weft yarns to evaluate the effect of the epoxy coating on their tensile performance. The ARG-TRC specimens with various volume fractions of warp yarn (0.24, 0.49, 0.73, and 1.09 vol%) and weft yarn (0, 0.20, 0.48, and 0.96 vol%) were subsequently tested, and their crack evolution and strain distribution were monitored and captured by the digital image correlation (DIC) method. It was found that the failure morphologies and tensile properties of ARG-TRC mainly depend on the volume fraction of warp yarn and the epoxy coating, while the effect of weft yarn is minimal. Furthermore, the effect of epoxy coating on the tensile properties of ARG-TRC is discussed with variations in the volume fraction of textile yarn. A simplified experimental fitting model is obtained by trilinear fitting and compared with the ACK theoretical model. The findings from this study can serve as a valuable reference for optimizing fabric configurations and designing TRC components.

Mitigation of Insert Separator Damage in Open-End Machines

Insert separators are part of the Open-end spinning machine that plays an important role in the process of feeding the fiber to the rotor. The function of the insert separators is as a conductor of drawing sliver which has been combed into individual fibers by adjusting the angle point of the insert separators. Damage to insert separators affects the number of slub yarns in the process of making Open-end spinning yarn. Consumption of using the separator insert continuously can make damage (eroded). The damage occurred during 20 days (four weeks) of 35.25 times of observation. The number of damaged separator inserts requires a repair whether the repair is done by patching, but in fact repair by patching is not an effective way, because the age of the patch only lasts approximately 1 week. Therefore, patch repair is not carried out, the best effort is to replace the separator insert.