Change of fabric gsm vary with yarn count

• Our target is to find out the easy process to get decision about yarn count selection, loop length selection, machine Diameter selection & machine gauge selection.. • We strongly think

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GENERAL INTRODUCTION

• Fabric is a manufactured assembly of fibres and yarns that has substantial surface area in relation to its thickness and sufficient cohesion to give the assembly useful mechanical strength Fabrics are most commonly woven or knitted but the term includes assemblies produced by felting, lace making, net making, non woven processes and tufting Our project basically is on knitted fabric specification and machines which are related to knitted fabric production

• The title of our project work is Analysis of knitted fabric specification and other related machine specification There are problem in our industries to produce knitted fabrics of required G.S.M Other specification like fabric width, fabric thickness is generally maintained in industries by previous data sheet For this reason there are problem if any order comes which didn’t produced in previous

• Our target is to find out the easy process to get decision about yarn count selection, loop length selection, machine Diameter selection & machine gauge selection

• We strongly think that by this process we can get decision about yarn count, loop length, machine gauge, and machine diameter for the single jersey, Rib and interlock fabric

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Aim of the project work

 Find out relation between yarn count and

GSM

 Find out the logic of selection of stitch length selection

LITERATURE REVIEW

• What is yarn

Yarn is a long continuous length of interlocked fibers, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery and rope making.

• What is Fabric

Fabric or cloth is a flexible artificial material that is made

by a network of natural or artificial fibers The example is

thread or yarn which is formed by weaving or knitting as

in textiles Cloth is mostly used in the manufacturing of clothing and household furnishings etc

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Weaving is a method of

fabric production in which

two distinct sets of yarns or

threads are interlaced at right

angles to form a fabric or

cloth The longitudinal

threads are called the warp

and the lateral threads are

the weft or filling The

method in which these

threads are inter woven

affects the characteristics of

the cloth.

Fig Interlacement of warp & weft

Knit ting

Knitting is a method by which thread or yarn may

be turned into cloth or other fine crafts Knitted

consecutive rows of loops, called stitches As each row progresses, a new loop is pulled through an existing loop The active stitches are held on a needle until another loop can be passed through

eventually results in a final product.

Fig Looping diagram

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Course: A course is predominantly

horizontal row of needle loops

produced y adjacent needles during

the same knitting cycle

Wales: A wale is a predominantly

vertical column of intermeshed needle

loops produced by the same needle

knitting at successive knitting cycle

A wale commences as soon as an

empty needle starts to knit

Stitch length: Is theoretically a single

length of yarn which includes one

needle loop and

adjacent needle loops on either side of

it

GSM = Grams per Square Meter A measurement system more

commonly seen in paper, but also seen in t-shirts, it measures the weight of the sheet (of fabric, paper, etc.), which will give you some indication of its thickness There are two formulas for calculating the GSM of knitted fabric:-

SOME MEASUREMENT NEED FOR

GSM CALCULATION

CALCULATION OF WALES PER INCH:

We calculated the number of wales in 10 inch fabric unraveling the yarn Then we divide the no of total wales by 10 inch to getting the wales per inch

CALCULATION OF COURSE PER INCH:

We calculated the number of course in five inch with the help of

counting glass and needle Then we divide the total no of course by five inch to getting the course per inch.

MEASUREMENT OF STITCH LENGTH:

In order to determine the stitch length, we count 100 no wales or

stitch and count its length by hanging the yarn on the stitch counter The reading is found in mm unit

MEASUREMENT OF YARN COUNT :

We have fallowed a different way to find out the count of the yarn At first we unravel a considerable no yarn from the fabric Then we measured the total length of the yarn and measured the weight of that no of yarn From these weights,

we find out the count of the yarn The equation we followed

is as

n-1 x 453.6 Count =

Yarn count is calculated in two systems :

Indirect system :

In this system the count of yarn express the no of unit length per unit

weight In this system higher the yarn count finer the yarn It is generally used for cotton, worsted, woolen, linen etc and the yarn count calculation formula is the following:

L x w Count=

W x l

Here, W = weight of sample.

L = length of sample

w = unit weight in system

l = unit length in system

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YARN COUNT

The following counts of yarn that are widely used for knitting

process are given:

RELATIONSHIP BETWEEN

KNITTING PARAMETERS

1 Stitch length increase with the decrease of GSM.

2 If stitch length increase then fabric width increase and WPI decrease.

3 If machine gauge increase then fabric width

decrease.

4 If yarn count increase then fabric width increase.

5 If shrinkage increases then fabric width decrease but GSM and WPI increase.

6 For finer gauge, finer count yarn should use.

7 Grey GSM should be less than finish GSM.

The following equations for

the selection of yarn count to

get required G.S.M

equations vary for fabric

types, fabric construction

List of equations are

• Lycra Single jerseyGSM = -4.9716 yarn count + 354.56

• Lycra 2 x 2 RibGSM = -8.2839 yarn count + 494.08

• InterlockGSM = -4.778 yarn count + 388

EQUATIONS FOR GETTING REQUIRED GSM FROM THE SPECIFIC YARN COUNT:

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Relation among GSM, stitch length and yarn count can be

derived from the following equation

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GSM α (When Yarn count and Stitch length both

Yarn count x Stitch length are variable)

• Different properties were found in Different knit structures according to stitch length, stitch density that means wales per inch, course per inch Loose structure that means higher loop length gives less GSM on fabric & compact structure that means shorter loop length gives high GSM on fabric

• In our project analysis, we observed that single jersey plain structure & 1×1 plain rib structure variation of calculated GSM with respect to actual GSM is too small But in single lacoste & polo-pique structure variation of calculated GSM with respect to actual GSM is high Because single lacoste & polo-pique structure are made by combination of knit & tuck loops They also analyzed that one knit loop consumes 30% more yarn than tuck loop So calculated GSM

is higher in single lacoste & polo-pique structure than single jersey plain structure & 1×1 plain rib structure

SOME FABRIC’S GSM IS SHOWED WITH

CHANGING YARN COUNT

RESULT & DISCUSSIONFrom our project work we manage to find the following equations for the selection of yarn count to get required G.S.M equations vary for fabric types, fabric construction The equations are tabulated below:

Relation between the fabric GSM and the yarn count:

If the GSM of the fabric is “x” and the count of yarn is “y”, then the

equation for determining GSM and the Yarn count is as follows:

GSM, x = 332 - 5.88y &

Yarn count (Ne), y = 56 - 0.17x

About this project learning thing is that fabric GSM change during production Different type of yarn and Yarn count has vary the fabric GSM It is also vary with stitch length, dyeing and VDQ pulley These parameters are responsible for GSM change From this project try to input some information for

how GSM depends on any other parameters.

So these things are should learn well to avoiding upcoming problem and increase productivity.

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