Uster Evenness Tester Research Articles

An analogical method for evaluating ring performance based on quality and production parameters

This study was carried out to determine the best ring size for a certain yarn count. In a ring frame with three separate rings of varying sizes, 20s/1 kW yarn was created. The spinning method used the same ring speed, twist, ring traveller, and spacer but three distinct rings with diameters of 38 mm (Ring- A), 40 mm (Ring- B), and 42 mm (Ring- C). Then, under the same testing conditions, ten samples of each yarn were examined by Uster Evenness Tester (UT-6) and compared to determine the best one. The “Ring- C″ production yield was 0.22% and 1.34% greater than the “Ring- B″ and “Ring- A″ yields, respectively. Yarn breakage for “Ring- C″ was 47.78% and 200% greater than for “Ring- B″ and “Ring- A,” respectively. Yarn unevenness for “Ring- C″ was found to be 4.15% and 4.14% higher than “Ring- B″ and “Ring- A,” imperfection of yarn produced by “Ring- B″ was 18.54% and 3.47% lower than “Ring- C″ and “Ring- A,” and tenacity of yarn produced by “Ring- B″ was 3.35% and 0.64% higher than “Ring- C″ and “Ring- A.” “Ring- C″ yarn hairiness was 10.63% and 12.31% higher than “Ring- B″ and “Ring- A″ yarn hairiness, respectively. According to the study of the tested report, yarn generated from “Ring- B″ delivered optimized results in terms of both quality and output. Ring “Ring- B″ had a lower production loss than Ring “A" but a higher loss than Ring “C.” Also, the hairiness of yarn made from “Ring- B″ was remarkably similar to yarn made from “Ring- A."

Qualitative and statistical analysis of cotton-flax blend yarn

Purely cotton fabric lacks different functional and physical properties than cotton-flax blends fabric. The experimental part of the present study is to investigate the influence of flax fibres content in cotton-flax blended yarn quality. Five ring yarn samples of the same count, 16/1Ne but from different blend ratios (100C, 80C:20F, 70C:30F, 45C:55F, and 100F) were produced from the same spinning preparatory conditions. The primary outcome was measured by analyzing test results obtained from different testing instruments (Uster Evenness tester, Mesdan Tensile Tester, and Instron Lea strength tester). The secondary outcome was measured by statistical analysis. Evenness properties were better for 80:20 blends in CVm% (17.13), IPI (1346), and H (6.89). 100% cotton yarn possessed the richest evenness quality CVm% (13.23), IPI (168.4), and H (7.97) in contrast to the poorest result of 100% flax yarn. On the other hand, the highest strength (CSP 4631, RKM 30.22) and the lowest elongation, 2.29%, were both achieved for 100% flax yarn. Evenness properties and elongation deteriorated with the gradual increase in flax content. In terms of strength, tenacity and CSP both decreased with an increase in flax content, but 100% flax yarn exhibited the highest performance.

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.

Investigate the Effect of Blending Technique on the Characteristics of Polyester Cotton Blended Yarn

Properties of blended yarns are mainly affected by fiber properties, blending techniques and stages. Recent development in spinning technologies such as blending techniques and machineries have significantly improved the yarn structure. The work presented here aims to investigate the effect of blending technique on the properties polyester cotton blended yarn. Tuft blending and roving blending techniques are used to produce 30Ne polyester cotton blended yarn maintaining 50:50 ratio. The properties of these yarns are tested on uster evenness tester (UT5), TENSORAPID and lea yarn strength tester. The results demonstrate that the roving blending yarns exhibit the higher yarn strength and yarn manufactured from tuft blending exhibit lower unevenness and imperfections.

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.

Analysis of Ring Yarn Properties Produced from Different Traveller Brands

A traveller is the tiny but significant part in ring frame in a short staple spinning mill. It is a small portion among all the parts of ring machine. It performs two most significant tasks like twisting without which spun yarn production cannot be imagined, and it aids in the winding of yarn on the cop. The traveller is one of the mechanical reasons for the hairiness properties of yarn. Two yarn of 30’s Ne KH (Card hosiery) was produced by using two same number of the traveller of different brands called Lakshmi Ring Travellers (LRT) and X-AXIS. All the processing parameters remained the same during the production of yarn. After that, Uster Evenness Tester 5 machine was used to determine the yarn properties such as unevenness percentage, imperfection index, hairiness, standard deviation of hairiness, standard deviation of hairiness in reference length 1 meter, and standard deviation of hairiness in reference length 3 meters. The end breakage rate was recorded through whole doff for the duration of the production of yarn in ring section. Statistical analysis used t-test to pair two samples to obtain the means for unevenness percentage, imperfection index, and hairiness. This was accomplished with Microsoft Excel 2013. Lakshmi Ring Travellers indicate better results than X-AXIS traveller. It can be decided from the t- test that there is no significant difference in unevenness and hairiness except imperfection index of two brands.

Statistical Analysis of Properties of Compact Yarn Produced from Different Process

Compact spinning system is a great modification of ring spinning system. It brings a revolution over ring spinning system in case of hairiness and strength of yarn. In this paper, three yarn of “34’s Ne” count was produced in three different spinning systems termed as conventional Ring, Suessen Elite compact, and RoCoS (Rotorcraft) compact spinning system. During processing, all the processing parameters and the environment were kept the same in the case of the compact spinning system. Yarn properties are then tested with Uster Evenness Tester 6 and Mesdan strength tester. Statistical analysis like t-test paired two samples for means for all the properties of two compact yarns such as unevenness percentage, imperfection index, hairiness, tenacity, elongation, and count strength product were performed using Microsoft Excel 2013. Suessen Elite compact spinning system shows good results than another compact spinning system. It was found from the statistical analysis that there is no significant difference in the maximum properties of two compact spinning systems, especially in hairiness and tenacity, as these two properties are crucial in the compact spinning system.

The Inspection of Raw- Silk Defects Using Image Vision

The inspection of defects is one of the most important aspects in the quality inspection of raw silk. We introduce a raw-silk defect detection system based on image vision and image analysis that is accurate and objective. In the experimental phase, we develop an image-acquisition section—which includes a charge-coupled device (CCD) image sensor, a telecentric lens, a light source, and a raw-silk winding device to capture the raw silk images steadily. After the image capture stage, an image-processing section tasked with threshold segmentation and morphology operations is carried out to obtain the defects of raw silk. To classify the raw-silk defects accurately and quickly, we propose an area method for the classification of raw-silk defects into five categories: larger defects, large defects, common defects, small defects, and smaller defects. Meanwhile, in order to recognize the common raw-silk defects—e.g., Bavella silk, nodes, and loose ends—that cannot be detected by the Uster evenness tester, the moment invariants of each segmented region of the images are extracted and used as the input of support vector machine(SVM).A SVM is designed as a classifier to recognize the samples. The experimental results show that the proposed method can recognize these common raw-silk defects effectively. According to the new classification and accurate recognition of raw-silk defects using the proposed method, we can improve the inspection standards for raw silk and advise raw-silk reeling enterprises seeking to optimize the technological parameters.

System Design for Evenness Measurement of Raw Silk

The evenness of raw silk is one of its most valuable qualities. Seriplane inspection is a common test for raw silk evenness but is prone to human error and lacks accurate repeatability; the Uster evenness tester is another common approach but is costly and vulnerable to environmental factors. An image-based raw silk evenness detection system is proposed in this paper. The system is comprised of an image acquisition segment with a CCD image sensor, telecentric lens, light source, over feeding device, and raw silk winding device, plus an image processing segment tasked with threshold segmentation and morphology operations. Images of the raw silk are first captured with the image acquisition segment, then the images are processed by threshold segmentation and morphology processing; the diameters obtained in this segment are then used to calculate the variation coefficient (CV), which characterises the evenness of the raw silk. We conducted three experiments to test the stability, repeatability, and accuracy of the system. The results showed that the system proposed is stable, repeatable, and accurate.

Measuring the unevenness of yarn apparent diameter from yarn sequence images

This article presents a novel method for measuring the unevenness of yarn apparent diameter based on yarn sequence images captured from a moving yarn. A dynamic threshold module was designed to gain the global threshold for segmenting yarns in the sequence images. In the module, a K-means clustering algorithm was employed to classify the pixels of each frame in the sequence into two clusters—yarn and background. The cluster center of the current frame was used as the initial value of the cluster center for the next frame in the sequence to expedite the segmentation process. From the segmented yarn image, the yarn core was further extracted utilizing the characteristics of yarn hairiness, and two judgment templates were adopted to remove burrs, isolated points and unrelated small areas in the images. The yarn apparent diameter was measured on the yarn core at a given interval. The same kind of yarns were tested by using this method and Uster Evenness Tester 5. The experimental results show that the proposed method can accurately detect the unevenness of yarn apparent diameter and provide new useful information about yarn unevenness, such as the short-term, the long-term, and the periodic variations of yarn apparent diameters.

Optimization of Opening Roller Speed on Properties of Open End Yarn

An experiment conducted to spun 6’s, 12’s count on well-maintained open end machine by changing opening roller speed i.e.,7000 and 8000 rpm. Present investigation reveals that, as increases opening roller speed yarn properties Like Rkm, Unevenness, total IPI improved, but there is marginal improvement in U% and RKM, and drastic reduction in total IPI, of the both yarn count. Investigation also summarized that as increases opening roller speed the cleaning intensity increases, deposition of trash in rotor groove increases leads to increase end breakages for both count. For reducing the end breakages frequency of cleaning rotors were suggested. This study also gives the difference between the properties of yarns which are produced from two different opening roller speeds. The quality parameters of the yarns produced were evaluated on an Uster Evenness Tester, the Uster Tensorapid with a testing speed of 250 mm/m and the UT4 with a testing speed of 400 m/m.

A New Measurement System of Yarn Appearance Based on Machine Vision

In this paper, a new yarn appearance measurement system based on machine vision is introduced. The yarn images are continuously captured by image acquisition system. To extract the main body of the yarn accurately, the yarn images are processed sequentially with threshold segmentation and morphological opening operation. Then the coefficient of variation (CV value) of diameter is calculated to characterize the yarn evenness. The measurement process achieves result (CV value) which can be compared with USTER evenness tester by image processing techniques. By comparing different methods which use different algorithms, a suitable method is chosen to be used in this new measurement system. Then a more accurate, more efficient and faster measurement system will meet requirements in the future.

A dynamic and robust image processing based method for measuring the yarn diameter and its variation

The yarn diameter is an effective property in determining fabric structure and processing settings. There are different systems of measuring the yarn diameter; among them is the image analysis of the yarn’s microscopic images. This method is considered to be more precise than other methods, but it is “static” in nature as it measures the property at scattered intervals and does not reflect the continuous variation of the yarn diameter. The goal of the current work is to measure the yarn diameter and its variation over a long length of yarn at fixed intervals to consider the “dynamic” change in the property. To achieve this goal, a high-speed camera (HSC) with a proper magnification was used to capture the images of the yarn and a new robust algorithm was developed to analyze the massive amount of yarn pictures in a reasonable time. The collected data for the yarn diameter were analyzed and compared to the results of the commercial Uster Evenness Tester IV. The results of the HSC were very comparable to the results of Uster and they were able to detect the short-term, the long-term, and the periodic variation of the yarn diameter.

A Computer-Based System for Evaluation of Slub Yarn Characteristics

This research aims to build a computer-based system for measuring slub yarn characteristics and evaluating the results using statistical methods. The measuring system was based on the electrical condenser of the Uster evenness tester as a measuring sensor. A digital storage oscilloscope was used to convert the analogue output signals into digital data to be recorded on a computer. A designed computer program was constructed using MatLab language for signal analysis based on a proposed method. Final results from this system contained graphical plots for the three measured slub yarn geometrical parameters slub length, slub distance, and slub thickness and a final report for all the measured slub yarn characteristics. The results of tested slub yarn samples showed that actual slub geometrical parameters differ from nominal values and the difference had two level: prevailing difference and outlier values. Outliers which are considered slub yarn defects were detected and counted in a final report using the box plot statistical method which could be an effective industrial tool for evaluation of both yarn quality and machine performance. The prevailing difference was assessed using histogram comparison which could help in adjusting the setting of slub yarn device to obtain the required appearance.

Properties Evaluation of Cotton Ring and Compact Spun Yarns after Scouring and Bleaching Process

Yarn prepared from two technologies i.e. Ring frame and compact spinning system analyzed on Uster Tensorapid, Uster Evenness Tester. It was observed that yarn prepared with compact spinning system gives less variation in end products. Study also reveals that there was significant difference between tensile properties of yarn which was produced from compact spinning and ring spinning. Yarn produced from two technologies pretreated with scouring and bleaching process and structural changes occurred in yarn were analyzed on Uster Tensorapid, Uster Evenness Tester. In the present investigation it was observed that yarn produces from both spinning technique shows, strength reduced and elongation improved in compact spun yarn and count C.V. also found reduced for both systems after scouring and bleaching process. It was noticed that, yarn produced from compact spinning gives less yarn hairiness because of reduction in spinning triangle and protruding fibers were goes into yarn body which gives very good impact on subsequent processes.

Evaluation of yarn evenness in fabric based on image processing

The traditional approach to unevenness characterization of yarn is based on the CV (i.e. coefficient of variation) of mass between defined portions of yarn measured with the USTER evenness tester. In fact, yarn with the same parameters has different evenness in fabric, and the evenness of yarn in fabric is different from the source yarn, which is caused by the producing process and parameters of the fabric. However, there is no good method to describe the appearance of yarn in fabric. The paper focuses mainly on a novel method known as yarn evenness in fabric (YEF). The method processes the image of the fabric and is divided into four steps. The first step is the acquisition of the relative image from the sample of woven fabric. The second step is the pretreatment of the image and segmentation of the warp and weft from the fabric based on fast Fourier transform and inverse fast Fourier transform. The third step is to separate the single yarn from the warp or weft sets by the gray unidirectional mean method. In the fourth step, the average relative thickness was selected for characterizing yarn. SD data of thickness that we will analyze in future is also a method. Experimental results on virtual and physical woven fabric showed that the method mentioned can obtain the fine information of yarn from fabric in details. The method of YEF was programmed by Matlab software. Computational burdens are about 11.4 seconds on average, for one meter of warp and weft yarn samples. The program could be valuable when applied to the practical industry.

Development of a new infrared device for monitoring the coefficient of variation in yarns

AbstractThe coefficient of variation (CV) in yarns is the most important evenness characteristic in textile processing and quality control. This article develops a new infrared device for monitoring the coefficient of variation in yarns, based on on‐line measurement of the yarn diameter, during the yarn manufacturing process. The device is composed of a 555 astable oscillator, four pairs of infrared emitters and receivers, a summing amplifier, an inverting amplifier, an alternating current (AC) to direct current (DC) converter, a unity‐gain second‐order Sallen–Key low‐pass filter, and a data acquisition system. The optimum values of some factors with the circuit, including the oscillator frequency, amplified gain, cutoff frequency of the low‐pass filter, sampling time, and number of sampling data to be averaged in the moving average method, are systematically chosen by the Taguchi method to reduce the variance in the output voltage of the device. The CV based on measured yarn diameter data is transformed to that based on mass profiles. The experimental results reveal that the CVs evaluated by the infrared device are close to those by the Uster Evenness Tester, which is verified by the statistical analysis of variance. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

A Comparison Between the Quality Attributes of Silk Yarn Using the Uster and Seriplane Test Systems

Six varieties of tussah and two varieties of mulberry yarn were assessed by using the Seriplane test method for various appearance grades and also on the Uster evenness tester. The correlation coefficients between evenness, cleanness, and neatness as determined by the Seriplane method and the mass irregularity (CV%), thick and thin place test and the neps as evaluated on the Uster machine, were determined in order to evaluate the strength association between them. Cleanness and neatness show a strong association between the thick places of the yarns and the Uster CV%.

A New Photoelectric Device for the Measurement of Yarn Diameter and Yarn Evenness Part III: Computer-aided On-line Measurement of Yarn Evenness on the Ring-spinning Frame

A new on-line measurement system, Onlineven, based on photoelectric principles, is evaluated for measuring yarn evenness. Descriptions of the sensor device used have been presented in Parts I and II of this series. Yarn specifications (linear density, twist) and measurement positions are the main topics discussed. Comparisons between Onlineven and the Uster Evenness Tester are also discussed. The results show that it is possible to use the Onlineven on-line-measurement system with yarn-guide wheels for the measurement of the yarn evenness at various linear densities (12.9–29 tex) and twists (590–1396 turns/m) at position 2. The differences in yarn evenness between Onlineven and Uster Tester III are all less than 5%. The mean deviation of yarn evenness of this system is small and limited to ±%.

A New Photoelectric Device for the Measurement of Yarn Diameter and Yarn Evenness. Part I: Improvement of the Variance of Radiant Intensity by Using the Area-compensation Method (ACM)

The diameter measurement of a moving and vibrating yarn with a photoelectric sensor device is difficult. Two main restrictions are concerned with the photoelectric measurement of yarn diameter and yarn evenness. One is the inhomogeneous radiant intensity of the emitted light on the sensor device, and the other is the irregular shape of the yarn cross-section. The improvement of the variation of radiant intensity in the horizontal light slot so as to obtain a homogeneous radiant flux in the test section by using the area-compensation method (ACM) is discussed in this study. The radiant-intensity distribution of an infra-red-emitting radiation was investigated by using the cubic-spline interpolation after the light had penetrated through a convex lens and a rectangular light slot. The ACM was then applied for obtaining a modified light slot, which was added to the convex lens. The ACM was developed according to the concept that the radiant flux is equal to the product of the radiant intensity and solid angle. Provided that the yarn diameter is constant, it is easy to determine the variance of an inhomogeneous radiant intensity. A steel bar of diameter 1 mm was applied for simulating the yarn diameter in this study. If the radiant intensity in this case is homogeneous, the projectile irradiance on the sensor would remain constant when the simulating yarn moved in the test section. The yarn diameter could be measured exactly in the homogeneous test section no matter how the yarn moved and vibrated. The coefficient of variation (CV%) of the radiant intensity decreased from 8.3% to 0.4% when the ACM was used. This sensor device was applied to measure the yarn-evenness variation of a 13.9-tex ring-spun yarn. The CV% decreased from 17.8% to 15.4%. Under the same testing conditions, the CV% was 14.3% with the Uster Evenness Tester. The variance of radiant intensity has accordingly been improved with the ACM.