project work -3

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Acknowledgement

At first I want to express that I am pleased to Almighty Allah for giving me a chance to study onTextile Sector and completing this industrial attachment successfully. Then there should be an issueof People's Republic of Bangladesh providing me a chance to study with a government host. Surely Iam happy enough to be a student of Pabna Textile Engineering College under educational curriculumof Rajshahi University where they made a rule to have completion of project work that is why I cameto M.M. Knitwear Ltd. Ambag Road, Konabari, Nilnagar, Gazipuir.

M.M. Knitwear Ltd. Ambag Road, Konabari, Nilnagar, Gazipuir with it's all staff with helpful mindgot a good place on my heart. Special thanks to Engineer Md. Nurul Islam (G.M Dyeing-M.M.Knitwear Ltd.) connecting me with M.M. Knitwear Ltd. and Engineer Md. Abdul Rashid (A.G.M.Knitting -M.M. Knitwear Ltd.) supervising me on the floor. Surely I got good response from machineoperators provided me best according to their ability. I remember my good time in Dyeing, Finishing

and Laboratory section. I thank to those other than Knitting , dyeing and finishing department helpingme as and when required. I can not stop myself without expressing a satisfactory mind blowingbehavior of Abdur Rashid sir (A.G.M Knitting-M.M. Knitwear Ltd.).

All of my teachers supported me well in my campus for this industrial attachment and withresponsibility A.K.M FARIDUL AZED of knitting department helped us best. Surely I am thankful tomy Principle for a nice co-ordination.

Finally thanks to all of my well wishers directly or indirectly related to this industrial attachment.


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TITLE OF THE PROJECT

Spirility and shrinkage problems in knitting industry andmeans to miminimige it .


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ABASTRACT

Spirality is a common problem in weft knitted fabric. It is the de-twisting tendency of yarn in

the fabric. It appears in mostly in single jersey fabrics but in double jersey fabrics this level in aboutzero. The causes of formation of spirality in twistness in the yarn and increase it by using morenumber of needles and multifeeders machine so on. It can reduce in different ways but not removefrom the fabrics.

So at first we collected some defected fabric samples from the knitting section, flat knitting section andwet processing section to commence our project work.then we targeted to find out the real cause ofspirility and shrinkage in the industrial arena these became possible during our industrial attachmentsprogram.

During our industrial attachment program we managed to see and collect different fabric

sampies and analyze them very effectively to find out and track to the source of those problems andhow to solve those problems.

We have tried out bet to give our complete effort on the spirility and shrinkage which wascaused by fabric manufacturing processes andwet processing processes.


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TABLE OF CONTENS

CHAPTER CONTENTS PAGE NO.

CHAPTER-I INTRODUCTION 6-10

CHAPTER-II RAW MATERIALS 11-13

CHAPTER-III MERKETING 14-16

CHAPTER-IV IMPORTANCE OF THE SURVEY 17-18

CHAPTER-V SPIRALITY & SHRINKAGE 19-21

CHAPTER-VI CAUSES OF SHRINKAGE & SPIRALITY 22-25

CHAPTER-VII METHOD TO MINIMISE THE SHRINKAGE & SPIRALITY 26-27

CHAPTER-VIII PROBLEM ASSOCIATED WITH SHRINKAGE & SPIRALITY 28-29

CHAPTER-IX CONTROL PARAMETER FOR SPIRALITY 30-32

CHAPTER-X CONCLUTION 33-34


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>> CHAPTER -1


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Introduction:

Evolution of Knitting Industries In Bangladesh:

Bangladesh had a historical reputation in production of textile products in addition tofamous Dhaka muslin. Fabrics from Bengal were found in ancient Egyptian tombs, and weretraded with the Roman and Chinese empires in the medieval age. In ancient Bengal a greatdeal of expertise existed with regards to weaving of textile products as well as greatreverence towards its trade. In rural communities both men and women were apprenticed inweaving. These skills and disciplines in sewing and weaving are passed down throughgenerations and are quickly transferred to production lines in modern knitwear factories.In the early 1980s, there were small-scale independent investments in the readymadegarments (RMG) sector. At that time, it was not considered viable and received very littlegovernment attention. Within a decade, the RMG industry in Bangladesh had flourished andby the early 1990s it had emerged as a major employer. Under the dynamic leadership of the

private sector together with policy support from the government, the export oriented RMGindustry has shown a spectacular growth during the last two and a half decades. The textilesector initially could not keep pace with the requirement of yarn and fabrics particularly bythe woven RMG sector as the textile and clothing industry was controlled by a fairly smallcommunity of local entrepreneurs. However, the sector grew with vengeance and the countrycurrently exports over US$11 billion in textiles and garments, with a projected target ofUS$24 billion dollars by 2020.Three independent associations are responsible for the textile sector: the BangladeshTextile Manufacturers Association (BTMA), which represents spinners, woven fabricmanufacturers and dyeing units; the Bangladesh Garment Manufacturers and ExportersAssociation (BGMEA), which represents the RMG sector, primarily the cutting and sewingunits; and the Bangladesh Knitwear Manufacturers and Exporters Association (BKMEA),which represents the knitwear fabric manufacturers, the fabric dyeing units and the knit

garment cutting and sewing units. These three associations work either in collaboration, orindependently from each other, subject to the agenda they may be forwarding. However, itshould be borne in mind that the bulk of yarn manufactured by BTMA members is consumedby members of the BKMEA, which at times leave the two associations at loggerheadopposing sides of an industry issue. The three main government departments that work forapparel sector are the Ministry of Textile and Jute, the Ministry of Finance and the Ministryof Commerce.Knitwear firms in Bangladesh are mainly located in Narayanganj district. Besides, a

few firms are also located in Chittagong, Dhaka, and Gazipur districts. The knitwearindustryin Narayanganj emerged at the early stage of the 19th century. Initially clothes wereknitted

from thread processed by wooden spindle wheels. Later handlooms were brought infromIndia. This transformed the local cloth industry into a specialized sector of hosiery items.Thehosiery sector expanded and accelerated in the 1980s and 1990s into knitting industrywhenthe expansion of RMG industry created demand for fabrics. The industry expanded bothvertically and horizontally to meet growing demand for fabrics within a few years.Besides,production of sweaters and socks, the major output of the knitwear industry involves twoprocesses; namely, knitting of fabric and making of knitwear using the fabric thus knitted.The present case study attempts to explore the following issues by focusing on a

selective number of knitwear firms in Narayanganj. How has the knitwear industryevolved?


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How has it sustained the successful performance? What are the sources of theindustryscompetitive strength? How are the structures of the constituting firms placed to productivitydifferentials within the dynamic performance of the industry? Are all firms growing at thesame pace or the composition is changing over time with some firms falling and some goingahead? What are the proximate factors that are causing the differential changes?

After this Introduction, section 2 highlights some features along the path ofdevelopment of the knitwear sector in Bangladesh. Section three sheds light on themomentum of the exports mainly to the EU and the US markets. Section four gives an idea ofthe production capacity and actual production of the sector. Section five attempts a ratherqualitative presentation of the internal dynamics of small, medium and large firms based on apurposively selected sample. Section six sketches the rise and fall of f irms within the sector.Finally, section seven makes a few concluding remarks.

Evolution of Knitwear Exports

The RMG business was initiated with the export of knitwear consignment in 1973.Eventually the RMG sector accelerated exports dominated by woven garments. The knitwear

sectors significant contribution in countrys export share was 1.1% in FY 82. Since then itgradually increased its share in exports. While the contribution of woven garments to the4export basket was 42.8% in FY 91, the knitwear sectors contribution rose to 7.6%. Table 1 presents export performance and the extent of retention rate due to high contents of domesticinputs. In FY 04, knitwear sector for the first time exceeded woven sector and became theleader with an exported quantity of 91.6 million dozens. The sector continues to be the leaderin terms of quantity exported with an increasing gap with the woven garments over time.Export quantity of knitwear items increased to 241.59 million dozens. This is roughly equalto 163.7% growth between FY 04 and FY 08. At present knitwear is the largest exportearning sector of Bangladesh contributing 41.8% to national export earnings at the end of FY09 (July-April).

Total Knitwear Exports and Net Retention in Bangladesh:

Exports (US $million)

Share of NetRetention

Share of

Year TotalRMG

Knitwear Knitwear(%)

(US $million)

NetRetention(%)

1994-95 1850.3 393.3 21.3 157.3 401995-96 2006.6 598.3 29.8 253.7 42.4

1996-97 2316.9 763.3 33.0 335.9 44.0

1997-98 2775.4 940.3 33.9 443.8 47.2

1998-99 2700.0 1035.4 38.4 530.1 51.2

1999-00 3125.4 1269.8 40.6 695.9 54.8

2000-01 3755.6 1496.2 39.8 837.9 56.0


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2001-02 3355.4 1459.2 43.5 826.9 56.7

2002-03 3601.4 1653.8 45.9 965.8 58.4

2003-04 4443.3 2148.0 48.3 1271.6 59.22004-05 5429.7 2819.5 51.9 1691.7 60.0

2005-06 6041.9 3817.0 63.2 2290.2 60.0

2006-07 7517.2 4553.6 60.6 2732.2 60.0

2007-08 8322.2 5532.5 66.5 3319.5 60.0

Source: Bangladesh Bank and BKMEA Website

Bangladeshi RMG products are mainly destined to the US and the EU markets. Withtheir earnest efforts from late 1980s the RMG exporters were able to export US$ 393.26million in FY 95. Of this amount, the shares of the EU and the USA were US$ 274 millionand US$ 98 million respectively. During FY 97, Bangladesh was the 7th and the 5th largestapparel exporter to the US and EU markets respectively. The cumulative average growth rateof the sector is about 20%. In recent years the EU market was the main export market for5Bangladeshi knitwear constituting 76% (US$ 4.2 billion) of total knitwear export followed bythe USA (14.59%, i.e. US$ 807 million) in the year FY 08. The impressive growth of theknitwear in the EU market was partly due the market access opportunities provided under theGeneralized Systems of Preference (GSP) facility. Further, the two-stage transformationrequirement of the rules of origin (ROO) introduced in 1999 accelerated market penetration

and deepened it in the EU. Since Bangladeshs knitwear production has very high domesticcontent of inputs and value added (around 80%) it is estimated that 95% of knitwear exportsto the EU enter free of duty under the EBA initiative, thereby contributing to very rapidgrowth of Bangladeshs exports of knitwear.

Social Impact:

The major strength of the Bangladesh textile industry is the pool of motivatedworkers. The sector has created jobs for about 2.5 million people (Table 4) of which 70% arewomen originating mostly from rural areas. Due to a liberal cultural attitude towards womenin the workforce, the RMG sector has transformed a traditionally male dominated society toone where women have an equal status as earners in the household (see Zohir and Majumder,1996). The number of factories in the RMG sector increased in tandem from less than athousand in FY 91 to about five thousands in FY 08. Competitive wage rate together witheasily trainable workforce helps transform the comparative advantages into copetitiveadvantage in this sector. Directly employed labor force in the knitwear sector are 1 million

and another 0.5 millions are indirectly employed.

The major impetus behind the phenomenal growth of the knitwear sector is the laborintensity in the production process. As the BKMEA claims, there were more than 2000thousand establishments in FY 95 which increased to about 5000 thousand in FY 08 implying5.88% growth per annum. Employment of workers grew in tandem. There were 1.5 millionworkers in FY 95 which increased to 2.5 in FY 08 implying a growth of 5.62% per annum.Comparing the number of establishments and the number workers employed one can discern

that average size of the firm did not change during the period. So, entry and attrition weremore or less simultaneous during the period.


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Number of Establishments, Employment, and Firm Size in the Knitwear Sector

Year Number ofEstablishments

Employment (inmillion)

Employment perFirm

1994-95 2182 1.20 550

1995-96 2353 1.29 548

1996-97 2503 1.30 519

1997-98 2726 1.50 550

1998-99 2963 1.50 506

1999-00 3200 1.60 500

2000-01 3480 1.80 517

2001-02 3618 1.80 498

2002-03 3760 2.00 532

2003-04 3957 2.00 505

2004-05 4107 2.10 511

2005-06 4220 2.20 521

2006-07 4490 2.40 535

2007-08 4740 2.50 527

Source: BKMEA Website


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>>CHAPTER-II


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RAW MATERIALS OF M.M.KNITWEAR LTD.:

Knitting section

Raw material is a unique substance in any production oriented textile industry. It .plays a vital role in

continuous production and for high quality fabric.

Raw material Types

1. Yarn 2. Fabric 3. Dye stuff 4. Chemical and auxiliaries

Yarn:

Sudhan combed, SSM Combed, Precot Combed, Maral, Srimatha, Nahar CombSlave, Sohag, Faisal

Sluv, Maral Sluv, Delta Viscos etc are purchased from India and local market.

Lycra:

1.Roica from Taiwan 2. Texlon Korea.

In knitting section, for knitting fabrics only yarn is used as raw materials. There are differenttypes of yarns are used as raw materials in this factory. These are

1. Cotton yarn:

(A).Combed.

(B).Carded.

2. Polyester yarn:

(A). Normal.

(B).Micro.

3. CVC.

4. Grey mlange.

5. Anther mlange.

6. Spandex (Lycra).

7. Different types of colored yarns for Auto-striper.


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SOURCE OF RAW MATERIALS:

Yarn Types. Yarn Count ource of Yarn100% Cotton, Combed. 40/s Shinha Tex100% Cotton, Carded. 40/s Rahmat Tex100%Cotton, Combed. 34/s Akij Tex100%Cotton, Carded. 34/s Shamim Tex100% Cotton, Carded. 32/s Shamim Tex100% Cotton, Carded. 30/s Akij Tex100%Cotton, Combed. 30/s Akij Tex100%Cotton, Combed 30/s Keya Tex100%Cotton, Combed. 26/s Akij Tex100% Cotton, Carded. 26/s Keya Tex100% Cotton, Carded. 24/s Akij Tex100%Cotton, Combed. 24/s Akij Tex

100%Cotton, Combed 20/s Keya Tex

Grey mlange(85% Cotton+15% viscose)

34/s Shamim Tex

Grey mlange () 26/s Shamim TexSpandex ( Lycra) 20/d Korea,Chine&Taiwan

Another source of raw materials is as follows

1.Jamuna Spg. Mill Ltd, 2. Paradise Spg. Mill Ltd 3. Utha Spg. Mill Lt

4. Amber Spg. Mill Ltd 5. Cotton concern Spg. Mill Ltd 6. J.K Spg. Mill Ltd

7. Square Spg. Mill Ltd 8. Talha Spg. Mill Ltd

Yarn Count

The following count of yarn that are widely used for knitting process

are given:

a. Cotton: 20/1,24/1,26/1,28/1,30/1,34/1,40/1 Neb. Terylene cotton: : 20/1,24/1,26/1,28/1,30/1 Nec. CVC: 26/1,30/1,34/1 Ned. Melange: 20/1,22/1,26/1,30/1 Nee. Spandex: 40D,70Df. Polyester:75D,150Dg. Sewing thread: 40/2,150D etc


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>>CHAPTER

III


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Marketing:

Marketing activities are done in this mill, Beximco Knitting Ltd. by a skillful team of marketing

officers under the Executive Director. Here are the details of marketing activities.

Buyer of M.M.KNITWEAR LTD:

S.L NO. BUYER NAME COUNTRY1 P&C, Germany

2 Katag, Germany

3 Ulla Popken Germany4 Mister & Lady Germany5 Tki Germany6 NewYorker Germany7 WoolWorth Germany8 Mustang Germany9 Pierre Cardin UK.10 Dunnes Stores UK.11 Heatons UK.12 Next UK.13 George UK.14 Matalan UK.15 Bhs UK.16 Spring Field Spain

17 Women Secret Spain

18 Gor Factory Spain

19 Hema Netherlands20 B.Young Denmark

21 Terranova Italy

21 Secure Italy

23 YSL France

24 Delta Plus France

25 Giordano Korea

26 Seven Hill Turkey

27 Colins Turkey

28 Mudo Turkey

29 LPP Poland


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Classification of Label:

BEXTEX have a small Label industry. They produce various typesof decorative labels. Labels can be classified as follows-

1. According to end use:Main Label: it is used to describe various types of information's like fiber composition of the

garment/textile, logo of the company, name of the manufacturing country etc.

Size Label:it is used to describe the size of the garment/textile, e.g. small (S), medium (M),large (L), extra large (XL) etc,

Extra Label:This type of label is introduced recently they are attached at the placket or atthe bottom part of the shirt or any other part.

Care Labels: It is used to describe care instructions or symbols like i.e. washing,bleaching, drying, ironing and/or dry washing etc.

Sticker Label:This type of labels is fancy items and is attached to various types of articles

either to show the brand names and other details or enhance their customer acceptability.

2. According to Fabric Construction:Plain or taffeta, Twill and Sateen. This is in fact theground weave of the label. The ground weave of labels can be taffeta, twill or sateen. There are goodreasons for using particular type weave.

3. According to use of Colored Threads: Labels produced from only ground yarns(without inserting any additional colored yarns). Labels produced from ground as well as colored

threads.Package Size and Label:

Most common sizes are

1. S =Small.2. M =Medium.3. L =Large.4. XL =Extra Large.5. XLL =Very Very Large.

Duties and Responsibilities of Marketing Officer:

1. Executive director takes order from the buyer and gives order the marketing officers troops toproduce a cost sheet.2. Marketing officers are known the amount and design of product.3. They collect the sample from the buyers and send to knitting and dyeing section.4. Knitting section adjusts the amount of total yarn and knitting conditions and dyeing sections

adjust the amount of dyes and chemicals. They send a rough calculation to the marketingsection.

5. Marketing officers adjust the amount of garments accessories with the help of their ownexperiences and their knowledge. They also take help of garments in charge.

6. Finally, they adjust their cost sheet after consulting with the Executive Director and copyseveral pieces of the cost sheet.


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>>CHAPTER IV


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IMPORTTANCE OF THIS SURVEY:

To get idea about the knitted fabric faults named spirility and shrinkage in knitting

industry.

To get knowledge about the cause of spirility and shrinkage.

To get knowledge about the processes to minimize spirility and shrinkage problems.

To get idea about the problems create for spirility and shrinkage.


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>>CHAPTER-V


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Spirality

Spirality is a dimensional distortion in circular plain knitted fabrics. The Wales or needle lines,

should occupy a truly vertical line in the fabric and should always be right angles to the cross wise

courses of stitches.

This perpendicularity of Wales to the courses is frequently, not the case and many times the Wales

may skew to the right or left forming an angle, which appears in the form of a twilled surface.

This geometrical defect has been termed Spirality of circular knitted fabrics. The following Figure

shows the fabrics with normal loop position and with Spirality having wale skewness.

Spirality has definite influence on both the functional and aesthetic performance of knitted fabrics and

their garments.

Displacements or shifting of seams during the garment make-up, mismatched patterns due to wale

skewness, sewing difficulties etc are some important practical difficulties due to spirality. As thedimensional properties of the fabrics are affected by spirality, it is very difficult to minimize or eliminate

it altogether.

This spirality problem is often corrected in finishing treatments by imposing distortion to fabrics so that

the wales straighten out and subsequently set in new from. Though the setting by finishing treatments

are normally achieved byusing resins, heat, steam, mercerization etc, it is not permanent and afterrepeated washings, the wale skewness takes place.

WalesWales

CoursesCourses

Fig: Fabric with normal loop Fig: Fabric with spirality

= Angle of spirality


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Shrinkage

A dimensional change resulting in a decrease in the length or width of a specimen subjected to

specified conditions is known shrinkage. Shrinkage is mainly due to yarn swelling and the resulting

crimp increase during washing in case of cotton fabrics. Yarn swelling percentage is more in

polyester cotton blending yarn.

Reduction in length and width of fabric induced by conditioning, wetting, steaming, chemical

treatment, wet processing as in laundering, in chemical practice and in literature the following terms

have been used to describe the shrinkage which occurs in testing procedure:

a) Relaxation shrinkage b) Felting shrinkage,

c)Compressive shrinkage d)Residual shrinkage.

a) Relaxation shrinkage:

During manufactures fabrics and their component yarns are subjeceted to tension under

varying conditions of temperature and moisture content, after manufacturing when the fabric

is taken from the machine and keep on floor or store room, then the fabric tends to shrink, this

type shrinkage is called relaxation shrinkage.

b) Felting shrinkage:

In case of wool fibers dimensional changes can be magnified by felting shrinkage. When

untreated wool fibers are subjected to mechanical action in the presence of moisture.

c) Compressive shrinkage:

A process in which fabric is caused to shrink in length by compression. The process often

referred to as controlled compressive shrinkage.

d) Residual shrinkage: after washing the fabric is shrunk. This type of shrinkage is calledresidual shrinkage. Residual shrinkage is the main factor of garments industry


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>>CHAPTER VI


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Causes Of Shrinkage:

i) Twist factor; twist factor increases so that shrinkage will be increases.

ii) Stitch length; stitch length increases so that shrinkage will be increases.

iii) GSM; GSM increases so that shrinkage will be decreases.

iv) Elasticity of yarn.

Causes Of Spirality:

The residual torque in the component yarn caused due to bending & twisting is the most

important phenomenon contributing to spirality. The residual torque is shown by its twist liveness.

Hence the greater the twist liveness, the greater the spirality. Twist liveness of yarn is affected by the

twist factor or twist multiplier. Besides the torque, spirality is also governed by fiber parameters, x-section, yarn formation system, yarn geometry, knit structure & fabric finishing. M/C parameters (no.

of feeder, m/c gauge etc.) also contributes to spirality. For instance, with multifeeder circular knitting

m/cs, course inclination will be more, thus exhibit spirality.

Influencing factors:

1) Count:

When the yarn dia reduces its resistance to deformation also decreases. It indicates

that deformation of loop structure is influenced by yarn count. In other words the finer the

yarn the more will be the spirality due to more twisting.

2) Twist:

(a) Twist multiplier:

We know, TM=TPI/count

So when TM is increased, TPI also increased & the spirality of fabric also increased.

TM Twist liveness(cm) Spirality(degree)

3.2 19.69 4.2

3.5 25.99 6.5

3.8 28.96 7.3

(b) Twist factor:

We know, TF= TPcm texSo, when TF is increased, TPcm also increased & spirality of fabric

also increased.

(3) Conditioning:

Atmospheric temperature & humidity also greatly affects the spirality.


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(4) Spinning method:

If yarn is produced in ring spinning system, that causes greater spirality than produced in

Rotor spinning & air spinning system.

(5) Blending of fibre:

100% cotton yarn shows more spirality than 50% polyester-cotton blend yarn.

(6) Fabric stitch length:

This is the length of one loop in knitted fabric, spirality increases with the decreasing of stitch

length.

(7) Fabric structure:

More spirality in s/j due to non-arrest of loops. By adding moisture to such a structure , the

twist will try to revert as it swells, that distorts the shape of the loop. In double jersey, the multifeed

pique & honey comb also show spirality even if sometimes two beds are used. Spirality can benoticed in certain jacquard structures. In stripe pattern it increases with the size. No appreciable

problem of spirality is there in ribs & interlocks.

(8) Fabric tightness:

Slack fabric presents higher spirality angle compared to tightly knitted fabrics. At each level of

yarn twist factor, the degree of spirality decreases linearly with fabric tightness factor.

(9) Fabric relaxation:

Fabric relaxation (dry & wet) treatment remover the residual knitting process. The relaxation

treatment relieves the residual yarn torque as a result of charges in the molecular structure &

increasing yarn mobility.

(10) M/C gauge:

In knitting terminology, no of needles per inches is called gauge. Smaller the gauge lesser will

be the spirality keeping other parameter constant. A proper combination of linear density gauge is

required to reduce spirality eg. Torque can be controlled in 20 gauge & 40s count.

(11) Knitting tension:

The effects of various knitting tension including the whole process of loop formation on fabric

spirality had been investigated by the researchers. Experimental investigation could not establish

consistent tends with respect to variations in fabric quality with knitting tension.

The twist factor of ply &single yarn, loop length & fibre dia has significant effects on the angle

of spirality, while yarn linear density & fabric tightness factor have comparatively lesser effect.

(12) Direction of m/c rotation:

Z-twist yarn gives z skew, s-twist gives s-skew to the fabric. With multifeed m/cs , the fabric is

created in helix, which gives rise to course inclination & consequently wale spirality . Direction

depends on the rotational direction of the knitting m/c. Earlier research work revealed that, for a

clockwise rotating m/c, the wale would be inclined towards the left. Thus producing the spirality.


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(13) Effect of fibre staple length:

In case of short staple fibre, cotton yarn liveliness is greater than viscose. So the produced

fabric spirality decreased with viscose yarn. The yarn with long staple length has less spirality

because of having less twist. For long staple fibre wool has less liveliness than the acrylic fibre.

(14) Effect of Ring & Rotor Yarn:

Spirality change between Ring & Rotor Yarn:

Dryrelaxedstate

Wetrelaxedstate

Washing at600C

Washing at800C

Washing at900C

RingYarn

4550.224

4.68 4.1 4.4 7.9 7.9

5050.262

6.71 5.05 6.1 9.3 9.5

5540.282

8.07 10.25 10.4 10.45 11

RotorYarn

5000.225

4.78 4.3 5.0 5.5 5.65

5500.279

5.48 4.3 5.65 7.0 7.1

6000.303

5.7 4.5 5.05 9 9.05

(15) Effect of combed or carded yarn:

In same count & TPI the carded yarn has more spirality than the combed yarn. Because

carded yarn needs more twist than the co9mbeed yarn.

(16) Effect of dyeing:

In case of dyeing with dark colors the spirality decreases and for light colors the spirality will

be increased.

0

1

2

3

4

5

6

0.224 0.279 0.303

SpiralityAngle(Degree)

Loop Length (cm)

Rotor Yarn

Fig: Dry Relaxed State


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(17) Effect of finishing: Among the finishing machines, the stenter machine controls the form of

spirality and this control point is continued during compacting.

(18)Effect of clothing: Spirality creates a big problem at the clothing step. It affects the garments as

the displacements of the side seam and this causes an important quality problem.

>>CHAPTER

VII


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Remedies Of Shrinkage :

1) In order to maintain the weight at a lower shrinkage, a finer yarn is used.

2) In order to maintain the width, a larger dia knitting machine or a longer stitch length is

necessary.

3) In order to maintain the same knitted tightness factor, or cover factor ( square root of tex

divided by stitch length) with a finer yarn, a shorter average stitch length must be knitted.

4) Changes in yarn count and stitch length also change the stitch density which again changesthe weight and the width for a given level of shrinkage. Changes in the tightness factor will

change the extensibility of the fabric and will also affect the amount of spirality (fabric

twisting) which may be developed.

Ramedies Of Spirality:

Compacting:

If the length of the fabric based on its elongation during processing which, in turn,

reduces the width. It helps in controlling the shrinkage of the fabric. There are two types ofcompactors, open and tubular. In tubular compacting the squeezing line gets on the sides in

this process and is done on natural movement thus controlling spirality. If the wales are

straightened manually then it results in spirality.

Yarn twist direction and machine rotation direction:

If the machine rotates clockwise then the spirality can be reduced by suing yarn of S-

twist. Otherwise if the machine rotates anti-clockwise the spirality can be reduced by using the

yarn of Z-twist.

Use of special type of yarn:

One comparative way minimize the spirality is to use the vortex spun yarn which is

obtained from Murata vortex spinning system. And modified friction spun DREF III yarn

reduces yarn snarling and fabric spirality.

By using plating yarn:

In fabric production when used plating yarn it reduce the spirality.


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>>CHAPTER VIII


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PROBLEM ASSOCIATED WITH SHRINKAGE:

Shrinkage is rated as one of the leading quality problems in the garments industry.Fabric shrinkage

can cause problem into main areas , either during garments manufacture or during subsequent

laundering by the ultimate customer.

Fabric relaxtion shrinkage may cause sizing problem ,as the finished garments will be smaller than it

was planned .It also leads in formation of puckeredseams infinal pressing.

PROBLEM ASSOCIATED WITH SPIRALITY:

Spirality has definite influence on both the functional and aesthetic performance of knitted fabrics and

their garments.

Displacements or shifting of seams during the garment make-up

mismatched patterns due to wale skewness

sewing difficulties etc are some important practical difficulties due to spirality.


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>>CHAPTER IX


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Considering the following parameters can control spirality:

count

The yarn is finer, the spirality will be more due to more twisting

Fig: Effect of spirality on GSM (34Ne Combed yarn) Fig-: Effect of spirality on GSM

(26Ne Carded yarn)

TWIST

Twist multiplier:

TM=TPI/count

So when TM is increased,TPI also increased & the spirality of fabric also

increased.

TM Twist liveness (cm) Spirality (degree)

3.2 19.69 4.2

3.5 25.99 6.5

3.8 28.96 7.3

3.5

3.6

3.7

3.8

3.9

4

4.1

4.2

4.3

175

GSM

178

GSM

179

GSM

180

GMS

182

GSM

2.4

2.5

2.6

2.7

2.8

2.9

3

3.1

3.2

175

GSM

178

GSM

179

GSM

180

GSM

182

GSM

Spirality(%)


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Twist factor:

TF= TPcm tex

So, when TF is increased, TPcm also increased & spirality of fabric also increased

Blending of fibre:

100% cotton yarn shows more spirality than polyester-cotton blend yarn on different

procedure of dry.

FOR 100% COTTON OF SINGLE JERSEY(FG-1) | FOR BLENDED (COTTON + POLYESTER)

OF SINGLE JERSEY (FG-2)

0

1

2

3

4

5

6

120 GSM(Tumble Dry)120 GSM (Hang Dry)120 GSM (Flat Dry)

Sp

i

r

a

l

i

t

y(

%)

Sample 1

sample 2

Sample 3

Sample 4

Sample 5

0

0.5

1

1.5

2

2.5

3

3.5

120 GSM

(Tumble

Dry)

120 GSM

(Hang Dry)

120 GSM

(Flat Dry)

Spirality(%)


33/34

>>CHAPTER-X


34/34

CONCLUTION:

In general the angle of spirality values are decreasing, when the tightness factor values are

getting tight in the all knitted fabric samples. In slack knitted fabric structures, the loop can

easily find area to rotate so spirality is increasing.

The spirality angle of the fabrics knitted with ring yarns are very high comparing with the

fabrics knitted with open-end yarns. This shows the effect of the spiraled on twist liveliness.

Because the twist liveliness of the ring yarns used in producing single jersey fabric is higher

than the open-end yarns used in producing single jersey fabrics.

Fabrics shrinkage depends on different fabric structure i.e; single jersey, rib, interlock and

their derivatives. Yarn composition i.e; 100% cotton and polyester and synthetic yarn.More research and development is required to control the fabric specifications accurately. We

could not able to execute the project work perfectly for limitations of time and lack of

opportunity to examine the various tests in the factory.

project work -3

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