7. Flow chart of Rotor yarn:
Input Machine Out
put
Raw material Blow- room Lap
Lap carding m/c
Carded sliver
Carded sliver Draw frame
Drawn sliver
Drawn sliver Rotor spinning
Rotor yarn
14. The following properties of cotton fibers are considered for
spinning.
oSpinning limit
oYarn strength
oYarn evenness
oYarn fullness
oDrop of the fiber product
oLuster
oHandle
oProductivity
oFibre fineness
15. Their description:
Fineness: It is measured in Micron air
value. The higher micron value the fibre
regarded as coarser.
Rating of MIC value
MIC Description
Less than 3.0 Very fine
3-3.6 fine
3.7-4.7 medium
17. Fiber length:
Staple length Yarn Quality
Fibre length influence
Spinning length
Yarn strength
Yarn evenness
Yarn hairiness
Handle of the product
Luster of product
Productivity
18. Length uniformity:
Length uniformity influences on-
Yarn regularity
Ends down
High wastage in combing.
High liberation and machine
contamination in spinning,weaving and
knitting.
19. Strength: Toughness of fiber has a direct effect
on yarn and fabric strength.
Fiber strength Yarn and fabric strength
Minimum Strength of textile fiber is
approximately 6 CN/Tex (about 6 k.m breaking
length)
Some significant breaking strength of fibers are:
Polyester: 35-60 CN/Tex
Cotton:15-40 CN/Tex
Wool: 12-18 CN/Tex
20. Fiber cleanness:
In additional to usable fiber, cotton contain
foreign matter of various kinds-
•Vegetable matter
•Mineral matter
•Other matter
Accept the range of foreign materials to the
bale:
Up to 1.2% Very clean
1.2-2% clean
2.0-4% medium
21. 4-7% Dirty
7 and above Very dirty
According to intemational committee for
cotton testing methods the following types
are to be distinguished:
Trash Above - 500 mm
Dust 50-500
Micro dust 15-50
Breathable below 15
22. Bale management: Testing, sorting and
mixing bales according to properties of
fiber for producing specific good quality
yarn at minimum cost is called Bale
management.
Object of Bale management:
An evening out of the quality
characteristics .
A means of avoiding quality jumps.
A possibility of reducing costs. As a result
of improved of the fiber characteristics
23. Importance of bale management:
If bale management is absent-
Lot to lot variation is called fabric barre
effect.
In weaving, shade , variation.
In knitted yarn, color variation.
24. About Mixing and Blending:
Mixing: If different grade of same fibres are kept
together , then it is called mixing.
For example: 50% of 1 and 1/8 staple length of
cotton + 50% of 1 ¼ staple length of cotton.
Types of mixing:
1)Volume mixing
2)Wt mixing
3)Hand stock mixing
25. 4) Bin mixing
5) Mixing by hopper
6)Lap mixing
7)Card mixing
8) Sliver mixing
9) Automatic mixing
Blending: When different fibres of same or
different grades are kept together, then it is
called blending.
26. Objects of blending:
To achieve uniform quality.
To improve processing performance.
To reduce and control of production cost.
To meet function and end used requirement.
Aesthetic i.e Fashion, texture ,drop luster etc
To give the required characteristics to the end
product.
To achieve effects by carrying color, fibre
characteristics and so on.
28. About blow-room
Blow room is consist of number of number of
machines used in succession to open and clean
the cotton fiber to the required degree . 40%
to 70% trash is removed in this section.
Blow room section: A section in which the
supplied compressed bales are opened,
cleaned and blending or mixing to form
uniform lap of specific length is called blow
room section. The cleaning efficiency of blow
room is 60%. This is the first section of spinning
line for spinning the cotton yarn.
31. Operation in blow room
1) Opening
2) Cleaning: To remove the dirt, dust. Broken
seeds, broken leafs , stalks and another
materials from the fibers
3) Blending or mixing: To make good value
of yarn and to decrease the production
cost by mixing different grade of fibers.
4) Lap formation :a) To transfer the opened
and cleaned fibers in to a sheet from of
define width and uniform unit length which
is called
32. Lap.
b)To roll the lap of predetermined length is
cylindrical shape around a lap pin.
c) To transfer the lap from . The lap pin to a rod
to suitable handle and feed it to substance
processing carding machine.