Yarn twist, yarn twisting system

1. Welcome To My
Presentation
Presentation ON
“ ”
Presented By: Md. Yousuf Hossain.
ID No. : 120103063
Thursday, April 23,
2015
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2. • 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
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3. 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.
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2015 3

4. Objectives Of Yarn Twisting:
 To hold the staple fibers together.
 To increase the yarn strength.
 To increase yarn evenness.
 Finer yarn has more twists.
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2015
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5. 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
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2015
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6. 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
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7. 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
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8. Twist amount is expressed in-
I. TPI (Twist per inch)
II. TPM (Twist per meter)
III. TPCm ( Twist per centimeter)
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23, 2015 8

9. 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.
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10. 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
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23, 2015
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