Imperfection Index Research Articles

Tuning drafting zone parameters for polyester yarn within a ring spinning system: modeling and optimization

Yarn is a fundamental element in most textile products. Among various yarn manufacturing methods, the ring spinning system is particularly important due to its benefits, such as high yarn quality, evenness, low hairiness, and ease of handling. The parameters of the drafting zone in this system greatly impact yarn quality. Typically, adjusting these parameters in the drafting zone is time-consuming and costly using trial-and-error method. This study introduces an algorithmic approach using response surface methodology (RSM), experimental modeling, and multi-objective optimization to decrease unevenness percentage (U%) and imperfection index (IPI). Input parameters optimized include cots hardness of front and back top rollers, spacer size, and break draft. Results showed that the artificial neural network (ANN) predicts response parameters superiorly with determination coefficient close to 1, compared to RSM, which has a determination coefficient of about 0.72. Therefore, ANN was chosen for optimization. Additionally, combining the genetic algorithm (GA) with two ANN-based models reduced IPI from 39 to 33.67 and a decreased from 9.73% to 9.67% occurred in terms of U%. The final Input settings were the cots hardness of the front roller of 70 shores and the cots hardness of the back roller of 76 shores, spacer size 2.8 mm, and break draft of 1.26. This method efficiently optimizes the drafting zone parameter, thus enhancing yarn quality.

Prioritising Yarn Quality Via Varying Top Roller Hardness: A Fuzzy Application

In recent years, the spinning or yarn manufacturing sector has seen remarkable technological advancements, emphasizing high-quality yarn production, especially for cotton combed ring spun yarns. In the case of better quality ring spun combed yarn, each part of the ring frame is significant. To fulfil this issue, this study focuses on understanding the impact of the drafting roller hardness on cotton-combed ring-spun yarn quality. It delves into how ten top and bottom roller hardness combinations influence yarn quality parameters. The cotton combed yarns underwent rigorous testing after spinning on ring frames with varying drafting roller hardness. Key quality parameters studied included yarn Imperfection Index (IPI), Unevenness (Ue%), Hairiness (Hi), Elongation at break (Eb%), and Count Strength Product (CSP), and Tenacity (Te). The primary insight was that extreme roller hardness adversely affects all parameters except Elongation at the break value obtained for the shore hardness value of 80/83. Yarns produced using medium-hardness rollers showcased fewer imperfections due to more consistent fibre flow and minimized drafting slippages, resulting in an even twist. These findings are pivotal for the yarn manufacturing industry, hinting at potential refinements in production methods. The usage of the Fuzzy DEMATEL (Decision-Making Trial and Evaluation Laboratory) methodology also determined that Te CSP) and IPI values significantly influence the combed yarn quality when adjusting roller hardness, whereas Hi is the least influential. Therefore, this study offers twofold insights: determining the optimal roller hardness and identifying the most affected quality parameters.

Optimizing yarn properties through response surface methodology: Finding the ideal flax and cotton fiber proportion in blended yarns by using design‐expert software

AbstractThe textile industries are looking forward to sustainable textile products. The bio‐based products are very important for protecting the environment, reducing carbon emissions, eliminating chemical pollution, and preserving the resources. These products provide economic advantages and strengthen communities with customer expectations for environmentally friendly items. In addition, sustainable practices encourage innovation and contribute to a healthier and adaptable environment, making them an essential textile product. Here the natural flax fiber plays a vital role due to its eco‐friendly behavior. Cotton‐flax blended yarns are manufacturing for perfect use of natural fibers and getting the better quality yarn than single product yarn. Here in this work it was trying to find out the perfect blending ratio by using Design‐Expert software. Because different blended ratio contain different characteristics. So it was trying to find out a perfect blending solution from the thirteen different ratios by using Design‐Expert software. This software analyses the blended ratios through statistical analysis. This study focuses on the unevenness (U%), imperfection index (IPI), hairiness (H%), tenacity (cN/tex) and elongation at break of the blended yarn. During the analysis the actual and predicted values were checked and it shows good significance, the correlation and regression analysis highlight the results of the samples summary. The findings of the study have great impact on the quality of cotton‐flax blended yarn, which impact on the quality of textile products. This work not only helps to understand cotton‐flax blending using Design‐Expert software, but it also highlights the possibility of using the perfect blended ratio by giving a solution.Highlights To identify the perfect blended ratio of flax and cotton fiber for producing blended yarn. Design‐Expert software has been used to find out the perfect response through yarn properties surface methodology. Thirteen experimental runs were trailed to find the perfect result.

Development of sustainable dual core-spun yarns using several filaments and recycled cotton sourced from pre-consumer fabric waste

Textile industries are now focusing on sustainable issues in manufacturing operations to save the environment. The study focuses on the use of cotton fibers (recycled) sourced from fabric (knitted) waste (pre-consumer) to manufacture elastic yarn (dual-core) for denim fabric. The study involves the production of yarns (dual-core) using a redesigned ring spinning method with different elastomeric components, including T400® (Polyethylene terephthalate)/Polytrimethylene terephthalate), Polybutylene terephthalate (PBT), Polyester (PES), Lycra® (elastane), virgin cotton and cotton (recycled) fiber. The study investigates various yarn (Ne 18/1) characteristics such as strength, IPI (imperfection index), elongation %, unevenness %, and hairiness. It is noticed that the elongation and strength of recycled yarn (double core) are lower and IPI (Imperfection index), unevenness %, and hairiness values are higher than 100 % cotton (virgin) yarn (double core). One-way ANOVA (statistical analysis) is employed to assess the significance of differences among yarns manufactured from various core materials and found significant variation for all characteristics. Additionally, the article introduces the MOORA (multi-objective optimization based on ratio analysis) technique as a decision-making tool to determine the best yarn among three alternatives (PES yarn, PBT yarn, and T400 yarn) based on their properties, considering attributes and finding T400 filament containing yarn as the best option. The study introduces a sustainable approach using recycled cotton in yarn (double core) production and employs decision-making tools to assess and rank the performance of different yarn alternatives.

Effect of core material draft ratio and denier on core spun yarn and denim fabric properties pre and post washing

Core-spun yarn (CSY) is utilized for better fabric characteristics like stretchability, durability, and comfortability. The study aims to investigate the influence of spandex drafts of core-spun yarn on denim fabric characteristics before and after washing treatment. Two types of denim fabrics were produced from two types of core-spun yarn, namely 16 + 40D, and 16 + 70D by applying 2.8, 3.0, 3.20 spandex drafts for 16 + 40D, and 3.40, 3.50, 3.60 spandex drafts for 16 + 70D. Prepared denim fabrics were desized, and acid-washed and the properties of denim fabric before and after washing were investigated as a function of spandex drafts and deniers. Accurate count, twist, and better elongation percentage were observed at 2.80 draft for 16 + 40D CSY and 3.4 draft for 16 + 70D CSY, but a higher imperfection index (IPI) value was obtained on those drafts. The strength of the denim fabric prepared with 16 + 40D CSY and 16 + 70D CSY were higher at 2.8 and 3.6 drafts, respectively. Higher shrinkage (%), ends per inch (EPI), and fabric weight of denim fabric was obtained after washing compared to before washing. The width of both fabrics decreased when the fabric was washed. Exploring various drafts of core material and their correlations with yarn and fabric properties provides valuable insights for textile manufacturers seeking to produce denim fabrics with optimum quality.

Prioritizing the quality parameters of cotton carded knit yarn by varying tensions of the bottom aprons of the ring frame

The forces exerted on fibres during drafting in the drafting zone with the upper and bottom aprons of the Ring Frame significantly impact the yarn quality. Aprons are crucial in manipulating fibres by facilitating movement and directing them toward the primary drafting area. From these two aprons, the bottom apron's tension is changed by changing tension spring bar groove hole positions. There is no scope for changing such settings in the case of top aprons. This research aims to achieve high-quality cotton carded knit yarn by selecting an appropriate bottom apron tension due to the significant role in proper drafting and twist insertion at the time of the manufacturing process directly affecting produced yarn's strength, evenness, imperfections, and hairiness properties. To fulfil this requirement, six yarn samples are produced each time by using 5 different tensions of the bottom drafting aprons. The samples underwent quality parameter testing, including Unevenness (U)%, Coefficient of Variation (CV)%, Imperfection Index (IPI), Hairiness (H), and Count Strength Product (CSP). The findings indicated that increasing the tension of the bottom apron while maintaining positions 1, 2, and 3 reduces the occurrence of neps, variations in thickness and thinness, and imperfections. In contrast, CSP is increased due to elevated stress on the fibres. In general, maintaining an appropriate tension enhanced the quality of the yarn, and the best quality was obtained for position 3, considering all the quality variables. Moreover, by using Interpretive Structural Modelling (ISM) methodology, the pairwise relationship between the quality variables is shown. Finally, after calculation, those quality variables are arranged in three levels. According to this level, the quality parameters are ranked where the top is the highest. It is observed that Count Strength Product is at the highest level, which indicates that CSP should be given more priority. Moreover, the end use of this yarn is to produce knit items, and for the knitting yarn, CSP is one of the most influential quality variables.

Effect of Cotton Yarn Imperfection Index on CSP

Effect of Cotton Yarn Imperfection Index on CSP

TRAVELLER CLEARER GAUGE CONSEQUENCE ON YARN QUALITY

Traveller clearer is an important part of the ring frame machine because, without it, fiber flying in the traveller cannot be cleaned. As a result, fiber congests travellers which may lead to a rise in end breakage rate as well as declination of quality of yarn. Six ring spun yarns of count 85’s tex were produced by using different traveller clearer settings and Burkina Faso cotton fiber was used as a raw material. Both High Volume Instrument (HVI) along with Advanced Fiber Information System (AFIS) was used for recognizing the fiber properties. The ring-spun yarn was produced from the roving count of 985 tex and spindle speed was kept at 7000 R.P.M. with Twist Per Meter (TPM) 492. Evenness properties, as well as strength of yarns, were measured with Uster Tester-6 and Titan Single Yarn Strength Tester respectively, and end breakage rate was studied. One-way ANOVA test was accomplished for all properties of yarn by using Microsoft Excel 2019. Traveller clearer gauge with 3.10 mm shows the best result among the other samples. Yarn properties such as imperfection index, hairiness, Sh (-), tenacity, and processing performance like end breakage rate express the best values. ANOVA result shows a significant difference for all properties except elongation.

Sustainable yarn production using leftover fabric from apparel industries

A huge amount of waste was generated from the apparel industries. This study aims to develop the process of producing recycled yarn from apparel waste. The apparel leftover fabric was converted to fiber, and the fiber was mixed with virgin cotton in different ratios to produce sustainable 6/1 Ne rotor yarn. The produced yarn qualities viz. count strength product (CSP), elongation percentage, total quality index (TQI) and tenacity were decreased linearly, and opposite scenario observed for thick and thin places, neps, imperfection index (IPI) and hairiness (H) attributes with increasing the amount of waste addition with virgin cotton. The leftover fabric (LOF) can be utilized to develop a sustainable yarn and to zero waste management.

Comparative Study of Cotton Yarn Properties Using Central-Fan and Multi-Fan for Vacuum Generation in Aerodynamic Compact Spinning Systems

Today, aerodynamic compact spinning is the most widely used compact spinning method in which the vacuum (negative pressure airflow) is generated to compact the fibre strands. Different manufacturers use different vacuum generation systems, which can be divided into the following – a central fan system with combined duct and independent duct and a multiple fan system. The information on each system and its impact on yarn properties would be quite attractive for research. This empirical study investigated the properties of yarns manufactured on the aerodynamic compact spinning systems with widely-used different vacuum systems. To preserve neutrality, these systems were referred to as CFS (CDS and IDS) and MFS instead of using their commercial names. It was found that CFS was the most remarkable concerning yarn irregularity (U% and CVm%), imperfection index (IPI), and bundle yarn strength (CSP) in comparison with the MFS. Though the yarn hairiness in MFS was better than in IDS, overall quality parameters were not as comparable to IDS or CDS.

Determination of suitable traveller for definite yarn count: A comparative study

The traveller imparts twist to the yarn and enables winding of the yarn on the cop. Yarn quality parameters can be improved by proper traveller weight selection which results in reducing yarn breakage, mass variation, twist variation and hairiness. High contact pressure (up to 35N/mm) is generated between the ring travellers during winding, mainly due to centrifugal force the pressure includes strong frictional forces which in turn lead to significant generation of heat. This is the kernel of the ring/ traveller problem. The low mass of the traveller does not permit dissipation of the generated heat in the short time available. Uster Evenness Tester 5 was used to determine the yarn properties such as unevenness, percentage, imperfection index, hairiness, standard variation of hairiness. Traveller number 5/0 was the best for card 30 Ne compare between traveller number 4/0 Most preeminence fact is that, the traveller speed remained same both for 5/0 and 4/0.

Analysis of Cotton Yarn Properties Spun on Aerodynamic Compact and Open-End Rotor Spinning

This article presents a comparative analysis of the properties of cotton yarn spun on aerodynamic compact spinning and open-end rotor spinning systems. Yarn samples with a linear density of 50 Tex, 37 Tex, 30 Tex, 25 Tex, and 20 Tex were spun both on the aerodynamic compact and rotor spinning systems using the same finisher drawn sliver of medium staple cotton which were produced by a specific mixing. The quality parameters such as mass variation, imperfection index, hairiness, and tensile behavior (strength in count strength product, elongation percentage) of the yarn samples were assessed and analyzed. The results revealed that aerodynamic compact spun yarn had a lower unevenness and mass variation, a higher imperfection in case of a finer count, less hairiness, higher tensile strength, and lower elongation% compared to the open-end rotor spun yarn samples. Finally, paired- samples t-test and regression analysis were carried out by using IBM SPSS 25 to check the significance of yarn quality parameters and correlation among them.

Investigating the effects of some process parameters on the quality of coarse compact yarn produced from carded roving

This project work aimed to investigate the interactive effects of carded roving parameters (i.e., roving hank and twist) and break draft of ring frame on the quality of compact yarn such as evenness, strength and hairiness. However, in this work, compact spun yarns produced from carded roving hanks of 0.70Ne and 0.90Ne while the roving twist per meter inserted at two levels (i.e., 40 and 45) for each of hank. Moreover, the break draft values of ring frame kept at three levels (i.e., 1.15, 1.25 and 1.35) for each type of roving. However, 100% cotton compact yarns of 24Ne and 32Ne produced for this experimental investigation. However, results showed that yarn unevenness (U%) and imperfection index (IPI) values of compact yarn decreased for the finer roving hank (0.90Ne) irrespective of yarn fineness. It was also noticed that low twisted roving improved yarn evenness during coarser yarn (i.e., 24Ne) production. Regarding the count strength product (CSP) value, increasing levels of roving twist deteriorated the CSP results in general. Trend of CSP results also revealed that finer roving produced higher levels of CSP results for comparatively finer yarn production. As far as yarn hairiness is concerned, it was observed that finer roving (0.90Ne) having higher levels of twist reduced yarn hairiness irrespective of yarn fineness without any exception. Finally, it can be said that this study will help the researchers for comprehending the influences of the process parameters during the production of compact yarn from carded roving.

Study on the Effect of Air Suction Pressure on the Quality of Compact Yarn by Changing the Frequency of Inverter

Compact spinning is the modification of existing ring spinning technology. The structure and quality of yarn are improved by using this spinning technique. This experimental work explores the effect of air suction pressure on the quality of compact yarn. Due to this reason, five samples of 52 Ne yarn were produced using different negative suction pressures such as 17 mbar, 19 mbar, 21 mbar, 23 mbar and 25 mbar (1 mbar = 100 Pa) in Suessen Elite@ system by changing the frequency of inverter. Samples were collected and then results were carried out. After that, the quality parameters of the produced yarn such as Mass variation (CVm%), Imperfection index, Hairiness and Count Strength Product (CSP) were analyzed along with calculating the power consumption against different suction pressures using the inverter frequency. Finally, the test results showed that yarn obtained from 23 mbar negative suction pressure was optimum considering the yarn quality and power consumption compared to others. This experimental work will provide an idea for spinners’ to choose optimum suction pressure for producing minimum imperfection and hairiness of compact yarn.

Understanding a Type of Forced Oscillation Caused by Steam-Turbine Governors

This letter studies the mechanism of a type of forced power system oscillation induced by imperfect nonlinearity compensation with a steam-turbine governing system. The nonlinear valve control characteristic of a steam turbine is usually compensated by its inverse characteristic performed by its governor for an overall linear characteristic of the governing system. In reality, a governing system may remain nonlinear due to imperfect compensation, which can result in a limit cycle forcing the generator and even an extensive neighboring area of the power grid to oscillate at a low frequency. A compensation imperfection index is proposed to evaluate the residual nonlinearity and discover how a limit cycle can occur and cause forced oscillation of a steam-turbine generator. Time-domain simulation on a real forced oscillation event caused by a steam-turbine governor validates the finding of the paper and supports the fact that opening the governor control loop of the oscillation-source generator can effectively eliminate this type of forced oscillation.

Modification of Adapter in Auto Cone Winding Machine for Better Performance

The economy of Bangladesh is largely depending on textile and garments industries at this moment. In this industry the overall demand of quality and cost reduction is increasing constantly along with steadily growing production capacities. For these reasons backward linkage industry like spinning plays a vital role for sustainable textile production in Bangladesh. Winding machine plays a significant role in quality of ring spun yarn in a spinning factory. Modification of adapter used in winding machine is accomplished in this work. Two diameter of adapter such as 58 mm and 68 mm was produced from nylon fibre and attached to the Muratec 21C winding machine. By using these two modified and one conventional metallic adapter three different fineness of yarn such as 30’s Ne cotton, 40’s Ne PC, and 50’s Ne cotton was produced by ring spinning machine in the same processing parameters. Those yarns were wound with 900, 1100, 1300, 1400 & 1500 m/min with original and modified adapters. After winding of yarn different quality parameters like unevenness (%), imperfection index (-), hairiness (-), Count Strength Product (CSP) were tested through Uster Evenness Tester 5 and Ele Stretch XT tester accordingly and compared them. Power consumption was measured by TRINITY (NF29) energy meter. It was found from the analysis of all test results that adapter of 58 mm performed the best; 68 mm made from nylon fibre the better among three along with cost savings is also possible in using nylon adapter.

Production and characterization of recycled polyester (r-PET) blend vortex and ring spun yarns

Nowadays, many major fashion brands are now producing recycled polyester (r-PET) textile products from PET bottles to contribute to sustainability. Of course, this means that textiles containing r-PET will now be produced at an increasing volume. R-PET fiber nowadays can be produced by optimizing machine settings only in the ring and rotor spinning systems. In this study, it is aimed to investigate the spinnability of r-PET fiber in the vortex spinning system. In this context, recycled r-PET fiber from PET bottle was blended with cotton (Co) and viscose (Cv) fibers in different blending ratios and yarns production were performed in ring and vortex spinning systems. Strength, elongation, unevenness (CVm%), imperfection index (IPI) and hairiness properties were determined and the results were statistically analyzed. In addition, it was determined that yarn production method, yarn composition and blend ratio had a significant effect on investigtated properties of the yarns.

Design and Optimization of Process in Spinning Mill to Improve Quality and Productivity of Yarn

Food, shelter and clothing are very basic needs of human beings. Cloths are used by the human beings to protect themselves from light, wind and rain and other environmental factors. Cloths are manufactured from the cotton. In spinning mill industry raw cotton is processed to produce yarn. At present condition quality and productivity of yarn is very important factor and lot of mills failing to achieve the quality as per standards due to this the spinning mills are in financial crisis. In India many spinning mills have stopped their production. So it has direct impact on economical condition of farmers, mill workers and the people who are connected directly or indirectly to spinning mill industry. As it’s affecting the life of many people it is very important to do research work in this field but still now this topic is not touched by researchers in large context. This is the reason why this research work initiated. Various continuous improvements processes are used in industries. Instead of applying single method at one time if we use two methods in integrated approach which compliments each other that will give benefits of both methods in single attempt. To achieve the fine quality of yarn the continuous improvement processes can be used like Six Sigma and Theory of Constraints. If we combine six sigma and theory of constraints and apply over a system as an integrated method that would give us benefits of both methodologies in single attempt with saving of time, money and man power and in results we can achieve fine quality of yarn with increased plant productivity and efficiency which will leads to profitability of mill. In this research by applying the integrated model bottleneck processes were found out and optimum solution is provided by doing improvements in processes. The process capability analysis was done before and after improvements done so we can measure the performance of system. Yarn properties such as unevenness, imperfection index, count variation, hairiness, strength, short fiber content are considered as parameters to measure effectiveness of system. In current system before improvements done there was lot of variation in values of this parameters and by reducing this variations integrated approach leads towards the profitability of spinning mill.

Effect of Blend Ratio on Cotton-Modal Fibre Blended Ring- Spun Yarn Quality with Varying Modal Fibre Percentage

Fibre blend ratio is an important factor that determines the properties of spun yarn. Modal is a regenerated man-made fibre and free from short fibres, neps, and impurities. In this paper, the influence of modal fibre in cotton-modal fibre blend ratio on the blended yarn properties has been studied. Cotton-modal blended yarn with blend ratio of 80:20, 70:30 and 50:50 and 100% cotton yarn of 30 Ne were produced in ring spinning frame. The properties of fibres, slivers, rovings and manufactured yarns were tested by using the Uster HVI, Wrap reel, Wrap block, Uster Evenness tester-5 and Lea strength tester. The experimental results show that the yarn quality parameters such as Um%, CVm%, thick places, thin places, neps, Imperfection Index and hairiness of 100% cotton are higher than cotton-modal blended yarns. With the increase of modal fibre percentage, the quality of blended yarns has been improved than 100% cotton yarn. In regards to the CSP value, the cotton-modal blended yarns show an increasing trend with increasing modal fibre percentage in the blend ratio. It can be attributed that the absence of short fibres in modal fibre which phenomena contributes to the yarn properties with increasing the modal fibre percentage.

Comparison of the Quality Parameter between Cotton and Melange process

The comparison of the quality parameter between Cotton and melange processes for different count and melange ratios have been studied. Here the yarns are produced from Indian cotton, Australia cotton, US cotton, China Black Viscose, and Indian Black Viscose (Melange). During the project work, different properties for the different machines in the same setting and ratios have been observed. All observations have completed by the latest model LMW (LR 9/AX) Auto Doffer Ring Machine. The quality parameters, for instance, mass irregularity (U%, CVm%,) Imperfection index (IPI), Count Strength Product (CSP), and hairiness were tested and then analyzed. For melange yarn, for different ratios, the best results have been given by 100% cotton yarn, because there is no blending between two different fibers. The quality parameter and characteristics have been presented for different types of fiber (100 % cotton, Black Viscose) and produced yarn (100 % Cotton, 5% Melange, 10% Melange, and 15 % Melange ratio) from the fiber. The productivity of melange yarn base on different condition is increased than 100% cotton yarn.