New Book-Compound Fabric Structure- Simplified

Compound Fabric Structure -Simplified !

A Step-by-Step Approach

A Book by 

Priyank Goyal

This book introduces the concepts of compound fabric structure in a very gentle way. A complement to the earlier book "Fabric Structure- Simplified", this takes the reader through the fabric structure variations in fabrics such as damasks, tapestries, brocades, terry pile, velvet, plushes, double cloth, and backed fabrics. A must for textile designers, this book is equally useful for textile technologists and textile chemists in understanding the complexity of these weaves in a simplified manner.

Order Here

What is Tapestry Weave

Tapestry is the name given to a weave in which two basic principles are found at play:

1. The hiding of the warp with a closely packed weft to secure solid planes of color.
2. Weaving of independent weft each confined to its own area within any given pick.

The places where the two colors junction intermingle, any one of the following methods may be employed:

If the two weft picks interlock each other, it is called interlock.

If the interlocking is on alternate rows it is called single interlock.

If it is practiced on each row it is called double interlock.

If the two weft picks interlock around a common warp without simultaneously interlocking with each other, it falls within the category of dovetail tapestry.

If there is no interlocking at color junction this is called slit tapestry or Kilim.

Now that you've finished reading this post, what are you going do? You should go join the Forum.

Twill Variations-1

This post is integrated into a book !! Order here

Introduction to Twill Weave

This post is integrated into a book !! Order here

Matt, Hopsack or Basket Weaves

This post is integrated into a book. Order here

Plain Weave Variations- Ribs and Chords

This post is integrated into a book !! order here

Plain Weave for beginners-1

This post has been integrated into a book !! Get it here

Fabric Parameters

Woven fabric parameters

There are four basic parameters that are essential for every woven fabric.

1. Ends per Inch and Picks per inch (EPI and PPI).
2. Yarn count
3. Crimp

4. Weave or Fabric Structure or Design

1. Ends per Inch or Picks per Inch

It is a measure of thread density. The normal method used to determine thread density is to use a pick glass.

2. Yarn count

EPI and PPI affects the compactness of the fabric. It is also known as thread count or cloth count. Thread counts range from as low as 20 threads per inch as used in tobacco cloth to as high as 350 threads per inch, found in type writer ribbon fabrics. Normally EPI and PPI of a fabric are described as EPI×PPI. Thus a fabric of 74×66 means 74 EPI×66 PPI.

Balanced constriction

A fabric is said to be well balanced if the number of warp yarns and weft yarns per inch are almost equal.

3.Crimp

Crimp refers to the amount of bending that is done by thread as it interlaces with the threads that are lying in the opposite direction of the fabric. Crimp is defined as the ratio of difference of length of yarn (Ly) taken from length of fabric (Lf) to the length of fabric (Lf).

Crimp = (Ly-Lf)/Lf

Often it is more convenient and preferable to use percentage values. Thus we can define crimp percentage as:

Crimp% = (Ly-Lf)/Lf

A crimp will normally give values ranging from 0.01 to 0.14 ie. (1% to 14%).

Crimp is related to many aspects of the fabric. It affects the cover, thickness, softness and hand of the fabric. When it is not balanced it also affects the wear behaviour and balance of the fabric, because the exposed portions tend to wear at a more rapid rate than the fabric. The crimp balance is affected by the tensions in the fabric during and after weaving. If the weft is kept at low tension while the tension in warp directions is high, then there will be considerable crimp in the weft and very little in the warp.

4. Weave

It refers to the arrangement of warp and weft in the fabric.

OTHER FABRIC PROPERTIES

1. Fabric weight (W)

It is the weight of the yarn per square meter in the woven fabric, which is the sum of the weight of the warp (W1) and weight of the weft (W2).

Weight of the warp is calculated as (per square m):

W1= [n1 x 100 (1+c1%)/100] x [N1/1000] g

Where
n1 = Ends per cm
N1 = Warp count in Tex

C1% = Warp crimp percentage.

Similarly weight of the weft is calculated as (per square m)

W2= [n2 x 100 (1+c2%)/100] x [N2/1000] g

Total weight per square meter = W1+W2

weight/piece = (W1+W2) × piece length × piece width in gram.

Example

A fabric 120m long, 1.3 m wide and having 30 ends per cm of 12 tex warp and 24 picks per cm of 15 tex weft. The warp and weft crimp percentages are five percent and eight percent respectively. We describe these fabric particulars as
30×24; 12 tex × 15 tex; 5%×8%

Warp weight per square m = [30 x 100 x (1+5)/100] x [12/1000] = 37.8 gms

Weft weight/square m = [24 x 100 x (1+8)/100] x [15/1000] = 38.8 gms

Piece weight

= total weight per m × piece length × piece width
= 76.68 × 120× 1.3
= 11962.08 gm or 11.96 kg.

2. Cover factor

(K) it is defined as the area covered by the yarn when compared with the total area covered by the fabric.
The warp cover factor can be found by using the formula.
k1= n1 x sqrt(N1)/10
Where
n1 = Ends/cm
N1 = Count of warp in tex

Similarly the weft cover factor can be found by the formula

k2 = n2 x sqrt(N2) /10

So the total cover factor is
K = K1 + K2

Thus with fabric (30×24; 12 tex×15 tex) the values are

k1= (30 x sqrt12)/10 = 10.39

k2 = (24 x sqrt15)/10 = 9.30

K = K1+K2 = 10.39+9.30 = 19.69

3. Fabric Thickness

For a wide range of fabric, this parameter is not important, but it becomes critical for fabrics that are to be used as belts and felts.

Want to Take a Quick Test on this Topic. Click Here

Textile Costing, Fabric design, Weaving Calculation, woven fabric formation

This is an amazing website on textile costing, fabric design, weaving calculation and woven fabric formation. A must for a web textile technologist.

Effect of Fabric Structure on Fabric Properties

Effect of Woven Fabric Structure on Fabric Properties

1. Tensile Strength: The more the crimp the less the strength. Other things being equal, plain weave fabrics which have the highest crimp have the lowest strength.

2. Extensibility: The more crimp there is in the yarn the more extensible is the fabric, therefor longer the floats, the less extensible is the fabric.

3. Surface Friction: Whether surface is smooth or rough. Long floats produce smooth fabrics with low crimp levels.

4. Tear Strength: In case of tensile loading, all the yarns in the direction of the loading share the load. In tear loading only one, two or at most few yarns share the load. In tight constructions, the movement of the yarn is restricted during loading and yarn will be presented to the load one by one; this results in a low tearing strength. Loose open constructions allow more freedom for the yarns to move and group together, thus presenting bundles of yarns to the tearing load, in consequence the tear strength is high. Designs which have group of yarns woven together such as rib or basket will have hight tear strength.

5. Abrasion Resistance: The most important factors are the crimp levels and the height of the crowns caused by the crimp. The greater the number of crowns/area or the greater the area of each crown, the less will be the stress concentration on the crowns and this leads to a high abrasion resistance. The longer the floats the larger the area of contact between the yarn and the abraidant and the higher the abrasion resistance.

6. Drape: Heavy fabrics from coarse yarns and dense constructions have poor drape characteristics. Fabrics with long floats in the weave permit the yarns to move freely; this reduces the bending and shear resistance of the fabric, leading to a better drape behaviour.

7. Crease Resistance: A plain woven fabric with a high fabric count puts a heavy strain on the fibres and limits the recovery of the fabric. The longer the floats, the higher will be the crease resistance of the fabric.

My lectures on the subject of Elementary Fabric Structure

Please view them/ download from them here