yarn properties

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YARN PROPERTIES

Twist: spiral turns given to the yarn to bind

individual fibres

Spun Fibres: short length fibres measured

in inches

Filament fibres: continuous length fibres

measured in meters.

YARN

A generic term for a continuous strand

of interlocked textile fibers or

filaments, in a form suitable for

knitting, weaving, or braiding

Yarn may or may not contain twist

YARN MADE FROM STAPLE FIBRES ALWAYS CONTAINS TWIST

YARN MADE FROM FILAMENT FIBRES MAY OR MAY NOT CONTAINS TWIST

Basis of difference

Filament yarn Spun yarn

Fibre length Short Continuous

Yarn Uniformity

Filament yarns are more uniform.

Less Uniformity

Yarn Smoothness and Luster

Smoother and lustrousExample: satin

Less smooth and somewhat dullerExample: Broadcloth

Yarn Strength

Stronger Weak Strength due to staple fiber.

Yarn Twist Low twist High TPI

FILAMENT AND SPUN YARNS

DIFFERENCE BETWEEN YARN AND THREAD

The main differences are:

Thread is used for sewing Yarn is used to construct fabrics (woven or

knitted)

A yarn is processed further to make a thread. A thread is usually a ply yarn, it is finer, more

even and stronger.

Thread

Yarn

Thread is always plied and twisted. These are mainly made up of cotton, nylon, polyester, rayon.

Thread is a tightly twisted strand

of two or more plys of yarn

Yarn may be single or plied, twisted or untwisted.

Left-twist  thread  is always used in

the sewing machine because the

action of the stitch-forming

mechanism tends to ravel or break

right-twist thread.

YARN TWIST

Twist is defined as the spiral arrangement of the fibres around the axis of the yarn.

Twist is produced by revolving the one end of a fibre strand while the other end held stationary.

Twist binds the fibres together.

Yarn twist is measured as the number of turns

per unit of length of a yarn

Twist is expressed as turns per inch (TPI), turns

per meter (TPM) or turns per centimeter (TPC)

TPI affects durability and appearance.

Two types of Twist

S Twist – spiral run upward to the right

Z Twist – spiral run upward to the left

The amount of twist varies with:1. Length of fibres 2. Size of yarn3. Intended use

Fine yarn require more twist then coarse yarns.

More twist in a yarn provide more strength to the yarn.

Low twist in yarn results in a lofty yarn.

Warp yarns need more twist than weft yarns

BALANCED YARN

Balance yarn is one which is having sufficient amount of twist.

If the twist is balanced, the yarn won’t kink back on itself.

It is very easy to work with and does not distort the finished piece.

Balance yarn is softer in feel.

UNBALANCED YARN

Unbalance yarn is one which is generally very highly or unevenly twisted.

The unbalanced yarn generally kink back on itself.

This yarns needs special care and requirements while weaving or knitting.

Unbalanced yarn; like crimp yarn is harder in feel.

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