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YARNNUMBERINGSYSTEMYM - 2011
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COUNT
A specific number relative indicator of fineness or
linear density of yarn.
Yarn count is also called as yarn number.
Two main groups for its measurement: Indirect or reciprocal yarn numbering system
(higher number ~ fine yarn i.e., light in weight)
Direct yarn numbering system
(higher number ~ coarser yarn i.e., heavy in weight)
Usually staple spun yarns are defined by indirect
while direct system is used for synthetic filaments,
but exceptions are there
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INDIRECT YARN NUMBERING SYSTEM
Yarn number signifies the number of units of a
standard length that are necessary to balance one
unit of standard weight.
There are different yarn numbering standards
depending upon the system on which a staple yarn
is spun.
If yarn is spun on cotton system then cotton
numbering system (Ne) is used and if yarn spun on
worsted system then worsted number system (Nw)
is used, irrespective of fiber type used.
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INDIRECT YARN NUMBERING SYSTEM (CONT..)
Spinning
system
Standard length Standard
weight
Numbering
system
common name
Cotton 840 yards (yd) 1 pound (lb) Cotton or
English (Ne)
Woolen 1600 yards 1 pound Woolen run(Nar)
Woolen 300 yards 1 pound Woolen cut (Nar)
Worsted 560 yards 1 pound Worsted (Nw)
All 1000 meters (m) 1 kilogram (kg) Metric (Nm)
Cotton count (Ne) for single yarn is written as: #/1 or #s
Worsted count (Nw) for single is written as the reciprocal as: 1/#
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INDIRECT YARN NUMBERING SYSTEM (CONT..)
Yarn
number
ing
system
Length
of test
yarn
Weight
of test
yarn
Calculation using standard
for a count of 1 (Actual
Standard)
Yarn
number
Cotton 840 yd 1 lb 840 yd/lb 1 lb/840 yd = 1s Ne
Cotton 12600 yd 1 lb 12600 yd/lb 1 lb/840 yd = 15s Ne
Cotton 12600 yd 0.5 lb 12600 yd/0.5 lb 1 lb/840 yd
=
30s Ne
Woolen 1600 yd 1 lb 1600 yd/lb 1 lb/1600 yd = 1 Nar
Woolen 3200 yd 1 lb 3200 yd/lb
1 lb/1600 yd = 2 NarWorsted 560 yd 1 lb 560 yd/lb 1 lb/560 yd = 1/1 Nw
Worsted 1680 yd 1 lb 1680 yd/lb 1 lb/560 yd = 1/3 Nw
Metric 1000 m 1 kg 1000 m/kg 1 kg/1000 m = 1 Nm
Metric 20000 m 0.6 kg 2000 m/0.6kg 1 kg/1000 m
=
33.33
Nm
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INDIRECT YARN NUMBERING SYSTEM (CONT..)
Yarn
numbering
system
Count of yarn
to be twisted
Number of
strands (plies)
twisted
together
Yarn number
Cotton
20/1 or 20s 2 20/2
15/1 or 15s 3 15/3
15/3 2 15/3/2
Worsted
1/20 2 2/20
1/15 3 3/15
3/15 2 2/3/15
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DIRECT YARN NUMBERING SYSTEM
Yarn number signifies the number of units of
standard weight that are necessary to balance one
unit of standard length.
Indirect system used two different standards:
Tex
Denier Tex is recognized as world standard yarn
numbering system.
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DIRECT YARN NUMBERING SYSTEM (CONT)
Yarn numbering
system
Standard weight Standard length
Denier 1 gram (g) 9000 meters (m)
Tex 1 gram 1000 meters
Decitex (Grex) 1 gram 10000 meters
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DIRECT YARN NUMBERING SYSTEM (CONT...)
Yarn
number
ing
system
Weight
of test
yarn
Length
of test
yarn
Calculation using
standard for a count of 1
(Actual Standard)
Yarn
number
Denier 1 g 9000 m 1 g/9000 m 9000 m/g = 1 Denier
Denier 100 g 9000 m 100 g/9000 m 9000 m/g = 100
Denier
Denier 200 g 12000 m 200 g/12000 m 9000 m/g = 150
Denier
Tex 1 g 1000 m 1 g/1000 m 1000 m/g = 1 Tex
Tex 100 g 1000 m 100 g/1000 m 1000 m/g = 100 Tex
Tex 100 g 9000 m 100 g/9000 m 1000 m/g = 11.11 Tex
Tex 200 g 12000 m 200 g/12000 m 1000 m/g = 16.67 Tex
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INTER CONVERSION OF NUMBERING SYSTEM
Yarn
Number
System
Symbolic
Abbreviat
ion
Unit of
Length
Unit of
Mass
Unit of
Yarn
Count
Constant
for
Conversi
on to Tex
Values
CottonCount
Ne 840 yd 1 lb 840 yd/lb 590.5
Woolen
(cut)
Nac 300 yd 1 lb 300 yd/lb 1654.0
Worsted Nw 560 yd 1 lb 560 yd/lb 885.8
Metric Nm 1 km 1 kg 1 km/kg 1000.0
For example:
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INTER CONVERSION OF NUMBERING SYSTEM
Yarn
Number
System
Symbolic
Abbreviat
ion
Unit of
Length
Unit of
Mass
Unit of
Yarn
Count
Multiplyi
ng Factor
Yarn
Number
to Tex
Tex Tt 1000 m 1 g g/km ---
Denier D 9000 m 1 g g/9000 m 0.1111
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DRAFT
The reduction of weight per unit length is known as
draft.
The fiber strand between two pairs of rollers is
stretched due to difference in surface speeds of
both pairs. In roller drafting technique, the front pair
of roller always moves at a faster speed than the
back pair, therefore draft is defined as,
Draft =
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DRAFT (CONT)
As the surface speed of front roller is always
greater than the surface speed of back roller,
therefore draft is always greater than 1.
(if in any case, S.S of F.R = S.S of B.R, no drafting
will be achieved;
If, S.S of F.R < S.S of B.R, negative drafting will be
achieved and the material being drafted will get
accumulated in between the two pairs of rollers)
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TYPESOF DRAFT
There are two types of drafting;
i. Dispersion drafting
ii. Roller drafting
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I - DISPERSION DRAFTING
The type of drafting in which the material attains an
irregular and dispersed form is called dispersion
drafting.
Dispersion drafting mainly performs opening and
cleaning actions. Straightening and parallelization
are also observed but to a short extent.
Dispersion drafting takes place in blowroom, i.e.,
scutcher and card machine.
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II - ROLLER DRAFTING
The type of drafting in which a minimum of two
pairs of rollers are used to keep the material in a
regular form, is called roller drafting. E.g., the
regular form may be sliver, roving etc
Roller drafting mainly performs straightening and
parallelization of fibers. Opening and cleaning are
not usually concerned in roller drafting.
Roller drafting takes places on drawing frame,
simplex and ring spinning frame.