This document describes a study that used the Taguchi design of experiments method to optimize the spirality angle of single jersey fabrics. Three factors were selected as control factors affecting spirality angle: relaxation treatment, yarn type, and loop length. Nine fabric configurations were produced based on an L9 orthogonal array. The average spirality angle and signal-to-noise ratio were calculated for each configuration. Analysis of variance and the average signal-to-noise ratios for each factor level were used to determine the optimum factor levels for minimizing spirality angle: dry relaxation treatment, open-end yarn type, and 0.25 cm loop length. The Taguchi method allowed determining the best combination of factors for low spirality angle using
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Process parameter optimization of SLM process and application of Taguchi appr...ijsrd.com
Selective Laser Melting (SLM) is an emerging powder based additive layer manufacturing technology that used to fabricate three-dimensional fully functional parts from metal powders by fusing the material in a layer by layer manner as per a CAD model. The quality of SLM produced parts is significantly affected by various manufacturing parameters of SLM machine. Hence optimization of SLM process parameters is necessary in order to improve the quality of parts. The purpose of this paper is to explore the reviews for various optimization methods used for process parameter optimization of SLM process and application of Taguchi approach. This review of work can be helpful to the other researchers to carry out further work in the same era.
Evaluation of physico mechanical properties of 1×1 interlock cotton knitted f...Elias Khalil (ইলিয়াস খলিল)
The Physico-Mechanical properties of knitted fabric can be changed due to use of various count of yarn, type of yarn (ring, rotor, and compact), quality of yarn, Loop length / Stitch length, structural geometry, fibre composition of yarn etc. This study focused on the various Loop length effect of grey interlock knit structure. With an increase in Loop length, the dimensional properties like CPI, WPI, GSM, thickness & tightness factor will be decreased; while comfort properties like air permeability & water absorbency will be increased. Again shrinkage & spirality will be decreased with increased Loop length at grey stage. Other properties such as bursting strength, abrasion resistance & pilling resistance improved with increased Loop length. Though all the tests for fabric properties were carried out for grey stage, there properties can considerably vary after further finishing of the fabrics. As finishing is mandatory for fabric production, so now-a-days, these kinds of tests are carried out after finishing stage & proper controlling is done according desired quality. Sometimes, controlling of some properties of finished fabrics are beyond our trial. In that case, analysis of fabric properties at grey stage can help us to take various control & corrective actions when necessary.
The Flexural rigidity of fabric’s bending stiffness is important for both consumer and industrial applications of fabrics. While fabric stiffness may not be wanted too high for a good drape in apparel and garment fabrics, it may be an important requirement especially for industrial fabrics to be used widely in heavy duty applications such as geotextiles and forming fabrics. For example, a forming fabric that easily bends under load and its own weight between the drive rolls may cause poor sheet formation during process.
An Investigation on Different Physical Properties of Cotton Woven Fabrics IJERA Editor
In this study, “An Investigation on Different Physical Properties of Cotton Woven Fabrics”, some sample fabrics were produced with plain, 2/2 twill, 3/1 twill and 4-end satin weave structure using four different weft counts. By means of regression, the correlation coefficient and correlation between different properties of fabrics were investigated. The findings of this study revealed that the crease recovery angle and the bending length are inversely proportional to each other. It was also found that with the increasing of weft yarn counts lead to a decreasing in stiffness, abrasion resistance and increasing in crease recovery angle. The pilling and wrinkle recovery affected very low by the increase of weft yarn count and for the variation of weave structure. Plain weave was superior to other structures in stiffness where as twill weave showed higher crease recovery.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Investigation on Optimization of Machining Parameters in Wire EDM using Taguc...ijsrd.com
In this paper, the parameters used in the cutting of Cemented Tungsten Carbide using wire electrical discharge machining (WEDM) with a Brass electrode was optimized using Taguchi method. Taguchi method is used to formulate the experimental layout and to analyze the effect of each parameter on the machining characteristics. Also it is used to predict the optimal choice for each parameter such as peak current, voltage, and pulse duration and interval time. It was found that these parameters have significant influence on machining characteristics such as Metal Removal Rate (MRR) and Surface Roughness (SR). The result of the work reveals that, the peak current significantly affects the Surface Roughness (SR) and the pulse duration mainly affects the Metal Removal Rate (MRR).
EFFECT OF NOSE RADIUS ON SURFACE ROUGHNESS DURING CNC TURNING USING RESPONSE ...ijmech
The work and study presented in this paper aims to investigate the effect of nose radius on surface
roughness, in CNC turning of Aluminium (6061) in dry condition. The effect of cutting conditions (speed,
feed and depth of cut) and tool geometry (nose radius) on surface roughness were studied and analysed.
Design of Experiments (DOE) were conducted for the analysis of the influence of the turning parameter on
the surface roughness by using Response Surface Methodology (RSM) and then followed by optimization of
the results using Analysis of Variance (ANOVA) to minimize surface roughness. The nose radius was
identified as the most significant parameter. Surface roughness value decreased with increase in nose
radius.
Fancy yarns are special products of spinning, twisting, wrapping, texturing and knitting, etc. The demand for yarns with structural and/or optical effects is due to the special aesthetic and high decorative appeal to the woven, knitted materials, and other textiles as well. Textile materials that are produced using yarns with effects find applications in normal and high fashion clothing.
Process parameter optimization of SLM process and application of Taguchi appr...ijsrd.com
Selective Laser Melting (SLM) is an emerging powder based additive layer manufacturing technology that used to fabricate three-dimensional fully functional parts from metal powders by fusing the material in a layer by layer manner as per a CAD model. The quality of SLM produced parts is significantly affected by various manufacturing parameters of SLM machine. Hence optimization of SLM process parameters is necessary in order to improve the quality of parts. The purpose of this paper is to explore the reviews for various optimization methods used for process parameter optimization of SLM process and application of Taguchi approach. This review of work can be helpful to the other researchers to carry out further work in the same era.
Evaluation of physico mechanical properties of 1×1 interlock cotton knitted f...Elias Khalil (ইলিয়াস খলিল)
The Physico-Mechanical properties of knitted fabric can be changed due to use of various count of yarn, type of yarn (ring, rotor, and compact), quality of yarn, Loop length / Stitch length, structural geometry, fibre composition of yarn etc. This study focused on the various Loop length effect of grey interlock knit structure. With an increase in Loop length, the dimensional properties like CPI, WPI, GSM, thickness & tightness factor will be decreased; while comfort properties like air permeability & water absorbency will be increased. Again shrinkage & spirality will be decreased with increased Loop length at grey stage. Other properties such as bursting strength, abrasion resistance & pilling resistance improved with increased Loop length. Though all the tests for fabric properties were carried out for grey stage, there properties can considerably vary after further finishing of the fabrics. As finishing is mandatory for fabric production, so now-a-days, these kinds of tests are carried out after finishing stage & proper controlling is done according desired quality. Sometimes, controlling of some properties of finished fabrics are beyond our trial. In that case, analysis of fabric properties at grey stage can help us to take various control & corrective actions when necessary.
The Flexural rigidity of fabric’s bending stiffness is important for both consumer and industrial applications of fabrics. While fabric stiffness may not be wanted too high for a good drape in apparel and garment fabrics, it may be an important requirement especially for industrial fabrics to be used widely in heavy duty applications such as geotextiles and forming fabrics. For example, a forming fabric that easily bends under load and its own weight between the drive rolls may cause poor sheet formation during process.
An Investigation on Different Physical Properties of Cotton Woven Fabrics IJERA Editor
In this study, “An Investigation on Different Physical Properties of Cotton Woven Fabrics”, some sample fabrics were produced with plain, 2/2 twill, 3/1 twill and 4-end satin weave structure using four different weft counts. By means of regression, the correlation coefficient and correlation between different properties of fabrics were investigated. The findings of this study revealed that the crease recovery angle and the bending length are inversely proportional to each other. It was also found that with the increasing of weft yarn counts lead to a decreasing in stiffness, abrasion resistance and increasing in crease recovery angle. The pilling and wrinkle recovery affected very low by the increase of weft yarn count and for the variation of weave structure. Plain weave was superior to other structures in stiffness where as twill weave showed higher crease recovery.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Investigation on Optimization of Machining Parameters in Wire EDM using Taguc...ijsrd.com
In this paper, the parameters used in the cutting of Cemented Tungsten Carbide using wire electrical discharge machining (WEDM) with a Brass electrode was optimized using Taguchi method. Taguchi method is used to formulate the experimental layout and to analyze the effect of each parameter on the machining characteristics. Also it is used to predict the optimal choice for each parameter such as peak current, voltage, and pulse duration and interval time. It was found that these parameters have significant influence on machining characteristics such as Metal Removal Rate (MRR) and Surface Roughness (SR). The result of the work reveals that, the peak current significantly affects the Surface Roughness (SR) and the pulse duration mainly affects the Metal Removal Rate (MRR).
EFFECT OF NOSE RADIUS ON SURFACE ROUGHNESS DURING CNC TURNING USING RESPONSE ...ijmech
The work and study presented in this paper aims to investigate the effect of nose radius on surface
roughness, in CNC turning of Aluminium (6061) in dry condition. The effect of cutting conditions (speed,
feed and depth of cut) and tool geometry (nose radius) on surface roughness were studied and analysed.
Design of Experiments (DOE) were conducted for the analysis of the influence of the turning parameter on
the surface roughness by using Response Surface Methodology (RSM) and then followed by optimization of
the results using Analysis of Variance (ANOVA) to minimize surface roughness. The nose radius was
identified as the most significant parameter. Surface roughness value decreased with increase in nose
radius.
Fancy yarns are special products of spinning, twisting, wrapping, texturing and knitting, etc. The demand for yarns with structural and/or optical effects is due to the special aesthetic and high decorative appeal to the woven, knitted materials, and other textiles as well. Textile materials that are produced using yarns with effects find applications in normal and high fashion clothing.
Fashion Marketing & Management Portfolio Erin Pearl
The Fashion Marketing & Management Portfolio is detailed coursework during my Bachelor's Degree Program. These courses have given me; beginner to mid level career knowledge and prepaired me for life experience within my field of study. Courses included are as follows; Product Development, Catalog Development, Stock & Inventory Control, Retail Buying, Retail Math Concepts, Business Writing & Special Topics, Public Relations, Fashion Show & Event Production, Apparel Evaluation, Visual Trends & Concepts, Portfolio 1 & 2, Professional Development, Art History & Costume History, and Textiles & Fabrications.
The compact spinning is a process where fiber strand drawn by drafting system is condensed before twisting it.Following methods are used by machine manufacturers to condense the fiber strand.
1. Aerodynamic condensing.
2. Mechanical condensing.
3. Magnetic condensing.
Compact spinning has a promising future because of the higher production and improved quality of compact yarns
Actually, I wanted to share my knowledge and experience with my younger brothers who are also in this same trade. And I wanted to give them the important hints for their easy understanding and reference. But while I was writing, I decided to write this also for others who are in this trade and who is interested to know about this trade. Then I decided to write this elaborately covering all the stages of this trade in detail. Also I have explained the details in very simple and easy language so that every one who reads this book can understand easily.
In this book, I have given the costs and costing in Indian Rupees, as it is easy for me. The readers, other than Indians, will have to convert the costs and costing in their desired currencies. I believe that the readers will bear with me for this inconvenience.
I am very happy to bring out my knowledge about this trade through this book and I have real happiness as I am sharing the details with you. Hope all the information in this book will be useful to you all and hope you will be satisfied. I wish you all success in your business or career!
The following terms & definitions are used to describe and explain cotton fiber maturity.
Circularity :
The degree of thickening which is calculated by the cross sectional area of the fiber wall divided by the area of a circle of the same perimeter.
Theta :
Average circularity of the matured fibers also described as the degree of thickening.
Fineness (mtex) : Average fiber fineness (weight per unit length) in millitex. 1000 meters of fibers with a mass of 1 milligram equals 1 millitex.
IFC (%) :
Immature fiber content in percent. Percentage of fibers with less than 0.25 circularity. The lower the IFC% the better the fiber is for dyeing.
Maturity Ratio :
Maturity Ratio is the ratio of fibers with a 0.5 (or more) circularity ratio devided by the amount of fibers with a 0.25 (or less) circularity. The higher the maturity ratio, the more mature the fibers are and the better the fibers are for dyeing.
Effect of count and stitch length on spirality of single jersey knit fabriceSAT Journals
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The following paper focuses on change in spirality due to stitch length and count variation .This work was carried out with 12 samples of single jersey knit fabrics which were scoured and bleached with NaOH and H2O2 (35% strength), dyed with reactive dye (Remazol Yellow RR reactive class) and were finished as standard procedure . After finishing the samples were tested for spirality and compared between different stitch length and count. The result obtained in this research indicated that spirality increases strongly due to increase of stitch length when count of yarn is fixed and on fixed stitch length spirality increases with the increment of count.
Keywords: Spirality, Count, Stitch length.
An Experimental Investigation of the Effects of Some Process Conditions on Ri...iosrjce
End breakage has a great effect on ring spinning productivity and also on yarn quality. In this
study, it was aimed to analyze the statistically significant processing parameters of ring spinning that have an
effect on the end breakage during the formation of ring spun yarn using the plackett burman experimental
design. In addition, the effects of the significant parameters on the end breakage of ring frame were
investigated. Our eight selected independent processing conditions were mixing ratio (CIS cotton/ Shankar-6);
Waste extraction% at blow room and carding; roving twist; break draft; spacer size; top roller pressure;
spindle speed and yarn count .Two levels for each independent variable were selected to conduct the study. For
this study, 100% cotton carded yarn samples were produced by Marzoli ring spinning frame and the results of
end breakage /100 spindles/hour were calculated and analyzed for all samples produced according to the
design of experiment. As a result, the parameters that have most significant effect on the end breakage during
the formation of ring spun yarn were obtained as waste extraction percentage at fiber preparatory stages viz.
blow room and carding, amount of roving twist, front top roller pressure and spindle speed of ring frame.
Finally, all the results of the statistical analysis were discussed and evaluated.
EFFECT OF TM AND LOOP LENGTH ON DRAPE CO-EFFICIENT OF SINGLE JERSEY KNITTED F...IAEME Publication
These are the days twist plays vital role in the hosiery yarn. The end applications of the knitted fabric are mainly depend upon the TM of Yarn. In this Research work cotton yarn and polyester cotton Blended (65%+35+) yarn used spun with same count of 30 Ne produced on Ring and compact spinning machines. Three TM levees are selected 3.32, 3.66, 3.94, to produce yarn on both spinning system. Three different loop lengths like, 0.27, 0.30 and 0.33 are selected produce single jersey plain knitted fabrics. Gamut of properties are studied with respect to geometrical and drape co-efficient of fabrics. The samples are washed for five cycles.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Study on the effects of ceramic particulates (sic, al2 o3 and cenosphere) on ...eSAT Journals
Abstract This paper investigates the sliding wear behaviour of three different composites. Three different reinforcements are under taken for this study namely SiC, Al2O3 and Cenosphere. Along with it percentage reinforcement is also varied from 8wt% to 16wt.%. Other factors applied normal load and sliding speed are also considered. Taguchi design of experimental technique is employed for the study of sliding wear. It is observed that SiC reinforced composites show better wear resistance than Al2O3 and Cenosphere reinforced composites. Regression and artificial neural network (ANN) is used to develop a model to predict the wear loss. It is observed that artificial neural network is more efficient than regression. Keywords: A. Metal-matrix composites (MMCs); B.Wear; C.Taguchi D. Nueral Network
This paper deals with the result of an investigation by using different count yarn but same
parameters of knitting machine to produce cotton-elastane single jersey fabric. Here,the all parameters of
knitting machine including gauge, dia ,Stitch length, rpm, machine tension etcare same. Dyeing process also
carried out at same parameter for all fabrics. Finishing process like Heat setting, Stentering, compacting are
done in same condition But we use different count cotton yarn. In this paper, we mainly deal with the physical
properties of single jersey cotton fabric. we try to identify how the properties of single jersey knitted fabric like
fabric diameter(gray& finished condition) ,WPI&CPI(gray& finished condition),Fabric GSM(gray& finished
condition),Shrinkage (%) length &width wise, spiralityare changing with Count .Finally the findings are as
expected with some variation with the result that are thought theoretically.
1. (REFEREED RESEARCH)
THE USE OF THE TAGUCHI DESIGN OF EXPERIMENT
METHOD IN OPTIMIZING SPIRALITY ANGLE OF
SINGLE JERSEY FABRICS
TAGUCHİ DENEYSEL TASARIMININ SÜPREM KUMAŞLARIN MAY
DÖNMESİ AÇISININ OPTİMİZASYONUNDA KULLANIMI
Serin MAVRUZ MEZARCIÖZ*, R. Tuğrul OĞULATA
Çukurova University, Department of Textile Engineering, Adana, Turkey
Received: 17.12.2010 Accepted: 05.09.2011
ABSTRACT
In this paper, spirality angle of single jersey fabrics was optimized using the Taguchi experiment design technique, which is a recently
famous approach. In the evaluations, analysis of variance (ANOVA) and signal to noise ratio (S/N) were used. Nine fabric configurations
with respect to L9 orthogonal design for Taguchi approach were knitted and tested. Relaxation treatment, yarn type and loop length,
effecting on spirality angle were selected as control factors. Based on the S/N ratio and ANOVA analyses, the optimum levels of these
parameters obtained in this paper, relaxation type of dry relaxation, yarn type of open end yarn, loop length of 0,25 cm. By using the Taguchi
experimental design approach, low number of experiments can be performed to achieve the combination providing the best performance.
Thus, before starting manufacturing in factory, it can be easily predict the spirality angle of single jersey fabrics using the defined factors.
Key Words: Experimental design, Taguchi design, Knitted fabrics, Spirality, Optimization.
ÖZET
Bu çalışmada, son yıllarda kullanımı yaygınlaşmaya başlayan Taguchi deneysel tasarımına göre süprem kumaşların may dönmesi
açısının optimizasyonu gerçekleştirilmiştir. Değerlendirmelerde varyans analizi (ANOVA) ve sinyal gürültü oranı (S/N) kullanılmış olup, L9
ortogonal dizaynına göre üretilen 9 farklı örme kumaş ile denemeler yapılmıştır. Relaksasyon türü, iplik üretim tipi ve ilmek iplik uzunluğu
may dönmesini etkileyen kontrol faktörleri olarak seçilmiştir. S/N oranı ve varyans analizine göre; relaksasyon türü olarak kuru relaksasyon,
iplik üretim tipi olarak open end iplik ve ilmek iplik uzunluğu olarak 0.25 cm bu parametrelerin optimum düzeyleri olarak elde edilmiştir.
Taguchi tasarımının kullanılması az sayıda deneme ile en iyi performansın elde edilmesini ve üretimden önce, belirli faktörler yardımıyla
may dönmesi açısının tahminlenmesini sağlamıştır.
Anahtar Kelimeler: Deneysel tasarım, Taguchi tasarım, Örme kumaşlar, May dönmesi, Optimizasyon.
* Corresponding Author: Serin Mavruz Mezarcıöz, smavruz@cu.edu.tr, Tel: +90 322 3386084 Fax: +90 322 3386126
1. INTRODUCTION
Fabric spirality is a major problem,
Wales direction
especially in plain knitted fabrics, and
comes mainly from two sources: from
the yarn and from the machine. The
spirality problem is that when we knit a
rectangular piece of fabric, it leans
towards one side and becomes a
parallelogram. The wales are no
Courses direction
longer at right angles with the courses.
The spirality is measured with an angle
θsp which is the angle between the
direction at right angles with the
courses and the distorted wale
(a)
direction as seen in Figure 1. If the
spirality angle θsp exceeds 5° it is
considered an important problem (1).
Wales direction
Courses direction
(b)
Figure 1. Schematic representation of spirality problem: (a) normal fabric; (b) spiral fabric
374 TEKSTİL ve KONFEKSİYON 4/2011
2. The Taguchi method, pioneered by Dr.
Genichi Taguchi and also called the
“robust design method”, greatly
improves engineering productivity (2).
Taguchi focused on minimizing the
effect of causes of variation. The
product or process performs
consistently on target and is relatively
insensitive to uncontrollable factors. In
comparison with a traditional full
factorial design of experiments,
Taguchi’s methods in general provide
a significant reduction in the size of
experiments, thereby speeding up the
experimental process (3). In Taguchi
design approach, there are three
design stages, which are system,
parameter and tolerance designs (2, 4,
5). The parameter design approach
has been adopted for studying the
effect of parameters on the spirality of
single jersey knitted fabrics.
Taguchi methodology for optimization
can be divided into four phases. viz.
planning, conducting, analysis and
validation. Each phase has a separate
objective and contributes towards the
overall optimization process (6-8). The
primary goal is to keep the variance in
the output very low even in the
presence of noise inputs. Thus, the
processes/products are made robust
against all variations (7).
Two major tools used in Taguchi
method are the orthogonal array (OA)
and the signal to noise ratio (SNR or
S/N ratio). OA is a matrix of numbers
arranged in rows and columns. A
typical OA is shown in Figure 2.
Factors
A B C D
1 1 1 1 1
2 1 2 2 2
3 1 3 3 3
4 2 1 2 3
5 2 2 3 1
6 2 3 1 2
7 3 1 3 2
8 3 2 1 3
9 3 3 2 1
L9(34)
Figure 2. L9(34) orthogonal array
Experiments
In this array, the columns are mutually
orthogonal. That is, for any pair of
columns, all combinations of factor
levels occur; and they repeat an equal
number of times. Here there are four
parameters A, B, C, and D, each at
three levels. This is called an "L9"
design, with the 9 indicating the nine
rows, configurations or prototypes
which are to be tested (9).
Taguchi suggests that the response
values at each inner array design point
be summarized by a performance
criterion called a signal to noise ratio.
S/N ratio is expressed in decibels (dB).
Conceptually, the S/N ratio (η) is the
ratio of signal to noise in terms of
power. Another way to look at it is that
it represents the ratio of sensitivity to
variability (4, 10). The higher the SNR,
the better quality of product is. The
idea is to maximize the SNR and
thereby minimizing the effect of
random noise factors has significant
impact on the process performance (5,
11).
Therefore, the method of calculating
the S/N ratio depends on whether the
quality characteristic is smaller-the-better,
larger-the-better, or nominal-the-
best (4, 8, 11, 12).
In our study, we adopt the “smaller is
better” approach. The S/N ratio for this
type of response was used and given
below:
S/N=
10 log 1 2 ⎤
(1)
⎥⎦
⎡
n
− Σ=
⎢⎣
n i
1
i y
Where; n is the number of experiments
in the orthogonal array and yi is the ith
measured value.
Taguchi design has been applied
many different areas, even in service
systems (5). However, studies about
application of Taguchi design in textile
industry are very new. Some
researchers used this design for
different textile process (2, 5, 13-22).
The effects of different characteristics
of the structure of knitted fabrics on
their spirality angle and prediction of
spirality angle have been investigated
by some researchers (23-27). In these
studies, correlations between spirality
angle and the structural parameters of
fabrics like stitch length, tightness
factor, yarn twist value, yarn linear
density, number of courses and wales
were investigated. In some of these
studies, the regression equations were
formed. In general, it was determined
that yarn twist value, loop length and
yarn linear density were the most
important factors on fabric spirality in
these studies. Also, any research has
been conducted on the spirality angle
of knitted fabrics from yarn and fabric
parameters using Taguchi design. In
the present study, it was focused on
optimizing the yarn and fabric
parameters affecting the spirality angle
of single jersey fabrics. For this
purpose, Taguchi experimental design
technique was employed. Firstly,
factors were chosen from cause-effect
diagram, which has an effect on the
spirality angle of the knitted fabrics.
Taguchi’s parameter design approach
has been used to plan, analyze and
confirm the experiments.
Determination of design parameters
Due to the difficulty and cost of
controlling certain parameters in
practical scenarios, this study
specifically emphasizes on factors
associated with materials, which can
be accepted as the major input.
During the relaxation treatment, knitted
fabrics tend to go back to the original
forms by getting away the stress.
Since relaxation treatment has
changed shape of the loop, it would be
affect the spirality angle of fabrics.
Also; the type of yarn production (ring,
compact and open-end) impressed the
physical features of yarns and fabrics
produced from these yarns would be
demonstrated different performance
properties. If amount of yarn that is
essential for one stitch are increased,
the fabrics are looser and its weight
decreases. Hence, some fabric
performances are affected.
So, relaxation treatment, yarn type and
loop length, effecting on spirality angle
are selected as control factors. Here,
yarn type is assumed as yarn
parameter, relaxation treatment and
loop length are assummed as fabric
parameter effecting on spirality angle.
After determining the control factors,
the levels of each factor have to be
determined. The most commonly used
yarn types were considered to
determine the levels of the factors.
Here, ring, compact and open-end
yarns were selected as the yarn type.
0.25, 0.28, and 0.32 cm were selected
as loop length (fabric tightness). Dry
relaxation, wash relaxation and full
relaxation were selected as relaxation
type. Used yarns were produced at
nearly closed machine settings each
other. As a result, each of the control
factors was evaluated with three
levels.
2. MATERIAL AND METHOD
100% cotton Ne 30/1 yarns were
knitted into single jersey structures on
Orizio circular knitting machine (28-
gauge 32-inch diameter, 2760 needle
count, with a positive yarn feeding
system). Yarn testing results are given
in Table 1. Table 2 gives the levels of
various parameters and their
designation.
TEKSTİL ve KONFEKSİYON 4/2011 375
3. Table 1. Yarn properties
Conventional ring yarn Compact yarn Open end yarn
Parameter
Ne 30 Ne 30 Ne 30
Actual count 29,36 29,36 28,80
Evenness U% 9,20 9,05 12,11
CVm % 11,60 11,40 15,23
Thin places (-50%)/km 0,3 0,0 59,2
Thick places (+50%)/km 7,1 6,6 75,3
Neps (+200%)/km 63,1 10,7 16,1
Hairiness 6,62 4,34 5,17
Breaking strength (gf) 354,1 381,9 226,2
Breaking elongation (%) 5,04 5,31 4,39
Rkm (kgf*Nm) 17,51 18,88 11,03
Breaking work (gf.cm) 482,7 535,6 283,2
Table 2. Parameters and their levels
Levels
Parameter Designation 1 2 3
Relaxation treatment
A
Dry
Washing
Yarn type
B
Ring
Compact
Loop length (cm)
C
0,25
0,28
Full
Open end
0,32
The following relaxation treatments
were applied to fabrics after knitting.
Dry relaxation: Fabrics were conditioned
for at least 24 hours in the standard
atmosphere (temperature: 20±2 ºC and
relative humidity: 65±2%). Washing
relaxation: After dry relaxation, fabrics
were washed in a domestic washer at
30ºC min 45 using 0.05% wetting
agent. After wetting, fabrics were
briefly hydro extracted. Then they were
conditioned in the same way as the dry
relaxation method. Full relaxation:
Washing relaxation procedure was
repeated for five times. Before tests
were taken, the fabrics were
conditioned for 48 h in a standard
atmosphere.
Measuring the angle of spirality, firstly
by using colored yarn on the knit
courses, the measuring areas are
determined. It is taken into consider
that for every fabric the measuring
areas should be in the same limits.
Spirality is measured from 5 points.
The angle of spirality is measured by
using a protractor between the specific
course direction, signed by using a
colored yarn and the wale direction,
which is followed from this course
direction. This test is applied according
to the IWS 276 test method (28). The
angle of spirality (θsp) method is
shown in Figure 3. All tests were
performed under standard atmospheric
conditions (temperature: 20±2 ºC and
relative humidity: 65±2%).
Figure 3. Measurement of the angle of
spirality
An L9 (33) orthogonal array table was
used. With three factors, each having
three levels, a total of 27 (33) full
factorial experiments to explore all
possible factor level combinations
would be required, and the cost and
effort of such experiments would be
quite large. However, the experimental
design of an orthogonal array required
only nine experiments. The L9(33)
orthogonal array table was shown in
Table 3.
Table 3. Orthogonal matrix for sample
production
Parameters
Order A B C
1 1 1 1
2 1 2 2
3 1 3 3
4 2 1 2
5 2 2 3
6 2 3 1
7 3 1 3
8 3 2 1
9 3 3 2
3. RESULTS AND DISCUSSION
Briefly, the Taguchi optimization
method consists of the following steps:
Each S/N ratio can be obtained from
observations according to the formula
of lower the better. For each significant
factor, the level corresponding to the
highest S/N ratio is chosen as its
optimum level. A search for the factors
that have a significant effect on the
S/N ratio is then performed through an
analysis of variance (ANOVA) of the
S/N ratios (2, 4). Table 4 shows the
average value of the spirality angle of
fabrics for each experimental point and
the S/N ratios calculated by formula 1.
It was seen that especially washing
treatments and increasing the loop
length rise the spirality angle in the
previous studies to be used the similar
materials. Closer results were also
found in this study.
For all levels, it was obtained average
SNR as shown in Table 5. Main effects
plotted for SNR is shown in Figure 4.
The largest S/N ratio (these were
indicated by rounding in the graph) for
each factor would be preferred. It
implied that the largest impact in
process consist of A1B3C1 respectively.
Minimum spirality degree levels
configuration for SNR are A1B3C1
which means that A (dry relaxation), B
(open end yarn), C (0.25 cm loop
length).
376 TEKSTİL ve KONFEKSİYON 4/2011
4. Table 4. Experimental layout using an L9 orthogonal array table and S/N ratio of experimental results
Factors and levels
Exp.
no
A B C Average spirality angle (º) S/N ratio (dB)
1 DR RY 0,25 8,2 -18,28
2 DR CY 0,28 12,0 -21,64
3 DR OEY 0,32 8,0 -18,09
4 WR RY 0,28 13,2 -22,42
5 WR CY 0,32 21,4 -26,61
6 WR OEY 0,25 4,0 -12,15
7 FR RY 0,32 22,4 -27,01
8 FR CY 0,25 10,0 -20,02
9 FR OEY 0,28 7,2 -17,19
DR: Dry relaxation, WR: Washing relaxation, FR: Full relaxation, RY: Ring yarn, CY: Compact yarn, OEY: Open end yarn
Table 5. Response table for S/N ratio
Average S/N (dB)
Factors
Level 1 Level 2 Level 3 Delta
A- Relaxation type -19.34* -20.39 -21.41 2.07
B- Yarn type -22.57 -22.75 -15.81* 6.94
C- Loop length -16.82* -20.42 -23.90 7.08
*: Optimum parameter level
A1 A2 A3
0
-5
-10
-15
-20
-25
-30
B1 B2 B3
S/N Ratio
0
-5
-10
-15
-20
-25
-30
C1 C2 C3
S/N Ratio
(a) (b) (c)
0
-5
-10
-15
-20
-25
-30
Figure 4. The effect of process parameters on S/N data-Factor A (relaxation type), factor B (yarn type), factor C (loop length)
Table 6. ANOVA table for the S/N
Factors Sum of
squares
Degree of
freedom
Mean
square
F
value
Prop Percentage
contribution (%)
Model 175,75 6 29,29 128,17 0,0078 -
A 6,43 2 3,21 14,06 0,0664 3,65
B 93,99 2 46,99 205,62 0,0048 53,34
C 75,34 2 37,67 164,82 0,0060 42,75
Residual 0,46 2 0,23 0,26
Total 176,21 8
R-squared: 0,997
S/N Ratio
3.1. ANOVA analysis
Statistical methods are powerful tools
for extracting useful information
contained in data and ANOVA is one
of the most frequently used tools (6).
ANOVA is the quantitative measure of
the influence of individual factors/
parameters. It is important for
determining the relative importance of
the various factors/parameters (29).
The end of results of S/N analysis was
used for realization of ANOVA. That
allows defining which factor and in
which level influences the final results
of experiments. ANOVA was
performed for S/N ratios with Design
TEKSTİL ve KONFEKSİYON 4/2011 377
5. Expert 6.0.1 statistical program
(α=0.05). An ANOVA table for S/N
ratio was given in Table 6.
The sum of squares, mean square, F
value, residual and also percentage
contribution of each factor were shown
in above ANOVA table. The degrees of
freedom (df) for each factor is
calculated as:
df = number of level – 1
With respect to Table 6, prob values
lower than 0.05 shows that the
established model is meaningful. Since
the value of R2 is 0.997,
expressiveness of the model is high.
This indicated that yarn type (B) and
loop length (C) the most significant
effect on fabric spirality values. The
contribution of different factors in
decreasing order as: Yarn type (53.34
%), loop length (42.75 %), relaxation
type (3.65 %) and undefined
parameters (0.26 %).
3.2. Confirmation experiment
Based on the S/N ratios and ANOVA
analyses, the optimal levels of all the
control factors’ combination were
identified. As mentioned before the
optimum setting of parameters is
A1B3C1. A confirmation experiment is
the final step of a design of
experiment. Its purpose is to verify that
the optimum conditions suggested by
the matrix experiment do indeed give
the projected improvement. The
confirmation experiment is performed
by conducting a test with optimal
settings of the factors and levels
previously evaluated. The predicted
value of multiple S/N ratio at optimum
level (η0) is calculated by formula 2.
j
( ) Σ=
η = η + η −
η 0 m i m
(2)
i
1
Where, j is the number of factors and
ηm is the mean value of multiple S/N
ratios in all experimental runs, ηi are
the multiple S/N ratios corresponding
to optimum factor levels (12, 30).
S/N ratio calculated for optimum level
as follow:
ηo=ηm+( ηA1-ηm) + (ηB3-ηm)+( ηC1-ηm)
(3)
ηo is optimum S/N ratio, ηm is the
overall mean of S/N values, ηA1 is the
average value of S/N at first level of
relaxation type, ηB3 is the average
value of S/N at the third level of yarn
type and ηC1 is the average value of
S/N at first level of loop length.
According to the formula 3, ηo was
found as -11.21 dB.
If the S/N is known and we want to
learn about the expected result that
will make the S/N. The procedure is to
back-transform S/N to find expected
performance value (8, 31).
When -11.21 dB value could be set
formula 1, obtained value is 3.63º.
Values of spirality angle of other
combinations will be expected with
same formula.
Also, knitted fabric was produced
according to the optimum design and
initial design. Spirality angle of these
fabrics was measured from five
different places of fabric. Average of
the results was determined as 4,20º for
optimum design (Table 7). This result
is very close to the result estimated by
Taguchi design (3,63º).
Initial design is accepted as A1B1C1
then S/N ratio is obtained according to
the initial and optimum design how
much profit is provided to find with
Taguchi design (Table 7).
Table 7 show that the improvement in
S/N ratio at the optimum level was
found to be 5,46 dB. The value of
spirality angle (º) at this optimum level
is 4,20 against the initial parameter
setting of 8,0. As a result, the
decrease in the value of spirality angle
can be obviously seen.
3.3. Prediction of spirality angle of
other conditions using Taguchi
design
According to the Taguchi design, it
was predicted the values of spirality
angle of knitted fabrics for seven
conditions (order) using formula 1 and
2. Predicted values were given with
their experimental results in Table 8.
Also, the values of percentage relative
error are evaluated, since software to
be used, shortening the numbers by
computer, personal mistakes are
considered.
As seen from Table 8, experimental
results and the predicted values are
much closed.
Table 7. Results of optimum and initial design
Optimum levels
Initial
Prediction Experimental
Design A1B1C1 A1B3C1 A1B3C1
Performance values (º) 8,0 3,63 4,20
S/N (dB) -18,07 -11,21 -12,61
Table 8. Comparison of experimental results with the predicted values from Taguchi design
Order A B C Experimental
(measured)
Predicted with Taguchi design
(calculated)
% Relative
error
1 2 2 1 8,22 9,12 10,90
2 1 2 3 19,62 18,26 6,93
3 2 3 2 6,00 6,21 3,50
4 2 1 3 18,11 20,18 11,4
5 2 2 2 13,00 13,80 6,15
6 3 3 1 5,10 4,61 9,61
7 3 1 2 14,67 15,20 3,60
378 TEKSTİL ve KONFEKSİYON 4/2011
6. 4. CONCLUSIONS
In this research, we intended to a
process for optimizing single jersey
fabric conditions using Taguchi design
to minimize the spirality angle of single
jersey fabrics. Firstly, important
affecting parameters for the spirality
angle of single jersey fabrics were
determined as relaxation type, yarn
type and loop length and an L9
orthogonal array was used in planning
the Taguchi experiments.
Based on the S/N ratio and ANOVA
analyses, yarn type and loop length
the most significant effect on fabric
spirality angles. Also, the optimum
levels of these parameters obtained in
this paper, which was A1B3C1; this
corresponds to relaxation type of dry
relaxation, yarn type of open end yarn,
loop length of 0,25 cm. In addition to
this, S/N ratio has been considerably
improved as compared to initial
parameter settings of the experiment.
Closeness of the results of the
predictions based on the calculated
S/N ratios and experimental values
show that Taguchi experimental
design technique can be used
successfully both optimization and
prediction.
As the loop length increases, spirality
angle increases. The reason for this
behavior can be explained by
concerning the chance of loops to turn
freely in loose fabric structure. Spirality
angle can also be increased by the
activity of fabric tending to reach
relaxation with washing process and
exchanges created by the wet
process. As already known, twist
direction in open end spinning is from
inward to outward, opposite of the ring
and compact spinning. So the amount
of twist is lower at the outer region with
respect to the inner region in open end
yarns. This means, the amount of
torque created in open end spinning is
lower with respect to ring and compact
spinning during the knitting process.
Because of these reasons, it is
predicted that the spirality angle of a
fabric knitted by open end yarns is
lower. Also lower values of twist
tendency created by yarn twist in open
end yarns support these results.
The main advantage of the Taguchi
parameter design, as opposed to the
classic factorial design methods, lies in
the introduction of noise factors in the
experimentation which provoke an
uncontrolled variation leading to a
noise insensitive response, therefore
to higher reproducibility. Taguchi
approach provides systematic, simple
and efficient methodology for the
optimization of the near optimum
design parameters with only a few
well-defined experimental sets and
determine the main factors to affect
the process. Taguchi design is an
important tool for robust design. It
offers a simple and systematic
approach to optimize design for
performance, quality and cost.
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