Yarn Twist- What is yarn twist

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  • Welcome To My Presentation

    Presentation ON

    Presented By: Md. Yousuf Hossain.

    ID No. : 120103063

    Thursday, April 23, 2015

    1

  • Fiber: A unit of matter characterized by flexibility, fineness, sufficient strength,

    elasticity and a high length to width ratio.

    Yarn: A grouping of fibers twisted together to form a continuous strand.

    Twist: Twist is the measurement of the spiral turns given to yarn in order to hold the fibers or

    threads together.

    Thursday, April 23, 2015

    2

  • Introduction

    In the manufacture of staple fibre yarns twist is inserted

    into the fine strand of fibres to hold the fibres together

    and impart the desired properties to the twisted yarns.

    Without twist, the fine strand of fibres would be very

    weak and of little practical use. A change in the level of

    twist also changes many yarn properties, such as

    strength and softness. This topic describes the nature of

    yarn twist, the effect of twist on yarn properties, as well

    as twist measurement.

    Thursday, April 23, 2015 3

  • Objectives Of Yarn Twisting:

    To hold the staple fibers together.

    To increase the yarn strength.

    To increase yarn evenness.

    Finer yarn has more twists.

    Thursday, April 23, 2015

    4

  • Real Twist: To insert a real twist into a length of yarn, one end of the yarn should be rotated relative to the other end.

    Types Of Yarn Twist:

    1. Real Twist 2. False Twist

    Thursday, April 23, 2015

    5

  • False Twist

    When inserting false twist into a length of yarn, both

    ends of the yarn are clamped, usually by rollers, and

    twist is inserted with a false twister between the

    clamping points, as indicated in figure

    Thursday, April 23, 2015 6

  • S-Twist: The direction of the twist or

    the spiral of the yarn is parallel to the

    center bar of the letter S.

    Z-Twist: The direction of the twist or

    the spiral of the yarn is parallel to the

    center bar of the letter Z.

    S-Twist Z-Twist

    I. S-Twist

    II. Z-Twist

    Thursday, April 23, 2015 7

  • Twist amount is expressed in-

    I. TPI (Twist per inch)

    II. TPM (Twist per meter)

    III. TPCm ( Twist per centimeter)

    Thursday, April 23, 2015 8

  • Relation Between Yarn Strength & Yarn Twist:

    Up to a certain point if the twist increase, the strength of the yarn will be increase.

    Further increase in twist the yarn will be weaker & finally broken.

    Thursday, April 23, 2015 9

  • Moisture absorption:

    High twist holds the fibers tight thus restricting water to enter.

    Low twist yarn is used where absorbency is required.

    Wearing properties:

    With an increase in twist level wearing properties (abrasion & pilling) are improved.

    High level of twist helps to resist abrasion.

    Effects of twist on yarn and fabric properties

    Thursday, April 23, 2015

    10

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