Part-1
Fibre
What’s are textile
fibre?
Ans.: Fibre
that can be spun into yarn or processed into textiles, such as fabric, knit,
lace, felt, non-woven etc, by means of an appropriate interlacing method.
Staple
Fibre: A fibre type with limited length which is generally measured. It
includes fibre of natural origin ( for example – Cotton, wool, jute, flexic)
and those obtained chopping filaments. Staple fibre needs to be processed in
the spinning machinery to transfer them into yarns.
Filament:-
A fibre type characterized by extreme length that is not measured. The extreme
length of filaments permits fabrication into Yarn without or with very low
twist and without the usual spinning operation required for transforming fibres
into yarns. Example of filaments are –
- Polyester
- Nylon
- Acrylic
- Spandex
- Silk etc.
- Physical Properties
- Tenacity / Specific strength (g/den0
- Length (cm/inch)
- Fineness (mic-value,
- MR% & MC% (Moisture Regain and Moisture Content) cotton 8.9
- Specific Gravity (g/c-c)
- Elongation (%) and Elastic Recovery (%)
- Initial youngs modulus (g/den)
- Breaking length (inch/cm)
- Extension (%)
- Maturity
- Swelling and water retention (%)
- Static Electrification
- Glass transition temperature (T9)
- Crystalline melting point (Tm)
- Discoloration
- Specific heatT
- hermal Conductivity
- Burning Behaviour
- Pilling behabiour
- LOI % (limiting Oxygen Index)
- Degradation
- ETC.
- Chemical Properties:
- Chemical Composition
- Effect of acids
- Effect of organic solvents
- Effect of insects
- Effect of micro organisms
- Structural Properties:
- Fine Structure and appearance
- Micro structures
- Cross – sectional view
- Longitudinal view
- Properties / performance in Application:
- Domestic application
- Business application
- Industrial application
- Technical application
Yarn
Yarn formation: Yarn is made from fibres. Primitive people discovered that a succession of short fibres could be twisted into a continuous yarn. The direction of twist way be absorbed by holding the yarn in a vertical position.
There are two types of twist in yarn.
Such as, 1)“S” Twist and 2)“Z” Twist.
If the spiral conform to the direction of
th slope of the central part of the letter “S”, the yarns has an “S” Twist.
If the spiral conform to the direction of
th slope of the central part of the letter “Z”, the yarns has an “Z” Twist.
The
amount of twist is an important factor for the yarn. It determines the
appearance service ability of the yarns. Fine yarns require more twist than
coarse yarns. Yarn may be soft-twisted, hard-twisted and maximum-twisted
depending upon the type of fabric to be woven.
What is spinning?
➡️The process of making yarns from fibres is called spinning. There are different methods of spinning for yarn preparation. Such as –
- For staple yarns:
- Ring Spinning
- Rotor or Open-end Spinning
- Friction spinning
- Self twist spinning
- Electro-static spinning
- Vortex Spinning
- Air jet-spinning
- Twist less- Spinning
- For filaments yarns:
- Dry spinning
- Melt spinning
- Wet spinning
- Bi-Component Spinning
- Bi-Constituent Spinning
- Film-Splitting
- For Integrated multi-component Yarns:
- Integrated composite spinning
- Cover spun
- Silfil yarn spinning
- Aero-dynamic spinning
Types of yarns: There are various types of yarn, each having its own characteristics. These characteristic very according to the construction treatment given in the manufacture of the yarn.
Machine in Blow-Room:
- Blender/ Mixing machine
- Hopper Ball opener / Breaker
- Cleaners: -
- Step / Ultra cleaner
- Vertical / Crighton opener
- Axiflow chamber
- Porcupin opener
- S.R.LL opener
- Beaters:
- Bladed beaters
- Krisher beater
- Hopper feeder
- Scutcher / lap former
Works of Machine:
Blow
Room : Mixing, opening and cleaning
Carding :
Individualization,Neps Remove, Sliver Formation
Drawing :
Parallelization, increase uniformity of weight per unit length
Lap
former : increase uniformity, lap formation
Comber :
short fibre remove
Simplex :
Roving formation,
Ring :
Produced Yarn
Autocone :
make yarn package that suitable for selling.
HVI:
High Valium Instrument,
the machine of fibre testing (Raw cotton Examine)
Yarn
numbering/Count:
840 yds = 1 hanks
No. of hanks × 840 yds = 1lb = Count
Example - 1: 40’s Cotton.
= 40’s Cotton = 40 hanks = 1lb
=
40 hanks × 840 yds = 1lb
=
33,600 yds = 1lb
Example – 2: 80’s
=
80’s = 80 hanks = 1 lb
=
80 hanks × 840 yds = 67,200 yds =
1lb
Example – 3:
The count of muslin cloths 300’s. past time
it made in Bangladesh. And this types of cloths are very famous in the whole
world
= 300’s = 300 hanks =
1lb
= 300 hanks × 840 yds = 252000 yds = 1lb
Process – Flow – Chart
of Combed yarn:
Combed yarn should be
60’s. In Bangladesh at last make 120’s
Denier:
It’s
the another unit of measured. It is an international unit.
= No. of gram/9000 m
Example – 1: Yarn – 1 = 10 denier
10
denier = wt of 9000m = 10gm
Example – 2: Yarn – 1 = 20 denier
20
denier = wt of 9000m = 20gm
Tex:
No.
of gm/1000m = tex
Example – 1: Yarn – 1 = 50 tex
50
tex = wt of 1000m = 50gm
Example – 2: Yarn – 1 = 25 Tex
25
Tex = wt of 1000m = 25gm
Example – 3: Yarn – 1 = 5 Tex
5
Tex = wt of 1000m = 5gm
SDC = Society of dyers
and Colorist (UK)
AATCC = American
association of textile chemist and colorist
Factors
Considered by the spinners during yarn manufacturing of Cotton Yarn: The following factors
of cotton fibres have been considered by the spinners
- The staple length of cotton fibres
- Fibres strength (0.5 – 3”) (ciailul cotton made in mishore)
- Fibre fineness
- Fibre maturity
- Trash content % [ in the fibre should less than 10%]
- Cleanliness of fibres
- Cost of fibres
Jute Yarn
Process
Flow Chart for the preparation of jute yarn:
Machine necessary for manufacturing of
jute yarn:
- Bacch Mixer
- Softening machine
- Carding Machine
- B/C
- F/C
- Drawing Machine
- Roving machine
- Spinning Machine.
Jute
fibre Characterized influences grading of jute,
- Fibre length
- Fibre strength
- Fibre fineness
- Fibre color
- Fibre uniformity of color
- Fibre luster
- Fibre cleanliness
Jute
grades
- A Bottom (High quality)
- B Bottom
- C Bottom
- X Bottom
- Habijabi (Low Quality)
Different
types of jute Yarn:
- Hessian warp
- Hessian weft
- Sacking warp
- Sacking weft
- Fine yarn
- Carper yarn / CBC yarn (Carpet Backing Cloth)
Yarn Count / Numbering:
The
count of a yarn is a numerical expression which defines its fineness
According
to textile Institute (UK) – Count is a number indication the “mass per unit
length” or the “length per unit mass” of yarn. Various counting system using
different unit of mass and length are in use.
Direct and indirect system of yarn
numbering:
Direct System: In a direct yarn counting system the yarn
number or count is , the weight per unit length of yarn. The units of weight
and length are very from trade to trade. A general formula which is applicable
for all direct system is given bellow.
Let, N = the yarn count or number
w = weight for the sample
L = the length for the sample
l = the unit of length of the system
So,
Yarn count,
N =
Math – 1: If a skin of 100m of filament viscose yarn weight is
1.67gm. Then what is the count of the filament (Denier / Tex)?
We know, N (denier) =
Here, w = 1.67gm
l = 9000m
L = 100m
So, N (denier) =
= 150.3 denier
And, again we know N (tex) =
Here, w = 1.67gm
l = 1000m
L = 100m
So, N (tex) =
= 16.7 tex
So, 150.3 denier = 16.7 tex
Indirect system: In Indirect system, the yarn number of
count is, the number of unit of length per unit of weight. The general formula
of indirect system can be written as follows.
Let, N = the yarn count.
W = weight of the sample
W = the unit of weight of the system
L = the length of the sample
L = the unit of length of the system.
Then,
N =
Math – 2: A lea (120 yds) of cotton yarn
weight is 25gm. Calculate its count in cotton count system or indirect system.
We know,
N=
Here, L = 120yds
w = 1lb
l = 840yds
W =
lb
|
1lb = 7000grains
|
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