Yarn is a long continuous length of interlocked fibres, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery, or ropemaking. It can be made of a number of natural or synthetic materials and comes in various colours and thicknesses (referred to as "weights").
2. Types of Yarn
• Carded Yarn.
• Combed Yarn.
University of Dhaka
3. Comparison of
Combed Yarn & Carded Yarn
University of Dhaka
Combed Yarn Carded Yarn
Comber is used No Comber is used
Less short fibers More short fibers
Less Hairiness More Hairiness
More Luster Less Luster
5. Flow Chart For Carded Yarn
University of Dhaka
Input Process/ Machine Output
Bale → Blow room → Lap
Lap → Carding m/c → Sliver
Sliver → Breaker Draw Frame → Sliver
Sliver → Finisher Draw Frame → Sliver
Sliver → Roving Frame
/Speed Frame/Simplex
→ Roving
Roving → Ring Frame → Yarn
6. Flow Chart For Combed Yarn
University of Dhaka
Input Process/ Machine Output
Bale → Blow room → Lap
Lap → Carding m/c → Sliver
Sliver → Pre comb drawing → Sliver
Sliver → Lap former → Lap
Lap → Combing → Sliver
Sliver → Post comb drawing → Sliver
Sliver → Simplex → Roving
Roving → Ring Frame → Yarn
7. Blow Room
Blow Room is called the mother of yarn manufacturing. It consists of
a 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.
University of Dhaka
14. Objects of Blow
Room
1. Opening :
To open the compressed bales of
fibers &
To make the cotton tuft a small
size as for as possible.
2. Cleaning :
To remove the dirt, dust, broken
seeds broken leafs and other
foreign materials from the fibers.
More…
University of Dhaka
15. Objects of Blow
Room
3. Blending & Mixing:
To make good value of yarn and
to decrease the production cost
by mixing different grade of
fibers.
4. Lap forming :
To transfer the opened and
cleaned fibers into a sheet form
of definite width and uniform unit
length which is called lap.
University of Dhaka
16. TECHNOLOGICAL
POINTS IN BLOW
ROOM
University of Dhaka
Opening in blow room means opening into small
flocks
The larger the dirt particle , the better they can be
removed
The higher the degree of opening, the higher the
degree of cleaning. A very high cleaning effect is
almost always purchased at the cost of a high
fiber loss. Higher roller speeds give a better
cleaning effect but also more stress on the fiber.
18. Actions involved
in Blow Room
1. Action of opposite spike:
(opening)
By The action of opposite spikes
opening the cotton fiber is done.
2. Action of Air flow: (Transport +
Cleaning)
During processing, the movement
of cotton from machines to
machine is done by air flow. It
also helps the separation of lint
and trash.
More…
University of Dhaka
20. Actions involved
in Blow Room
3. Action of Beaters: (Cleaning &
Opening)
Beaters are responsible for
removing almost all of the
impurities extracted in the blow
room. Beater also helps in
opening of cotton fiber.
4. Action of regulating motion:
(Uniform output)
The action of regulating motion
gives the uniform output.
University of Dhaka
21. Cleaning Efficiency
University of Dhaka
Cleaning efficiency of blow room can be fin out by the following
simple calculation.
(Input Trash - Output Trash)*100
Input Trash
22. Problem
Find the Blow Room cleaning effy :
Raw cotton trash= 6%
Lap trash = 1.6%
Solve: (6-1.6)*100/6
=73%
University of Dhaka
23. Carding
Carding may be defined as the
reduction of an entangled mass of
fibers to a filmy web by working
between two closely spaced,
relatively moving surface closed
with sharp wire points.
University of Dhaka
24. Objects of
Carding
University of Dhaka
Opening to individual
fibers.
Elimination of Impurities
and dust.
Fiber blending.
Sliver formation.
25. Flow diagram of
Carding m/c
• A = Cylinder
• B = Flat
• C = Taker in
• D = Feed roller
• E = Feed plate
• F = Doffer
University of Dhaka
26. Actions of Carding
m/c
1. Carding Action
This is the action between flat & cylinder.
• Pin direction: Opposite.
• Rotation: Opposite.
27. Actions of Carding
m/c
2. Stripping Action
This is the action between Cylinder - Taker
in
• Pin direction: Same.
• Rotation: Same.
28. Actions of Carding
m/c
3. Doffing Action
This is the action between Doffer &
Cylinder.
• Pin direction: Opposite.
• Rotation: Same.
29. Actions of
Carding m/c
4. Combing Action
This is the action between Feed roller &
Taker in.
• Pin direction: Same.
• Rotation: Same.
University of Dhaka
32. Draw frame
• It is a process of yarn manufacturing in which the sliver is
elongated when passing through pairs of rollers, each pair
faster than the previous one.
University of Dhaka
33. Actions involved in Draw frame:
Drafting: The process of increasing length per unit weight of sliver. It is mainly
due to varying speed of the rollers.
Doubling: The process of combining two or more carded sliver into a single form
is called doubling. In draw frame m/c generally six to eight slivers are fed and
converted into one.
Drawing = Drafting + Doubling.
University of Dhaka
34. TASKS OF DRAW FRAME
Through draft fibers get parallelized
Hooked fibers are straightened.
Through the suction ,intensive dust removal is achieved.
Blending can be done here.
University of Dhaka
37. University of Dhaka
Find out the
production/shift in lbs of
a modern draw frame,
from
the following particulars:
Delivery speed = 600
m/min, No of
delivery/frame = 2, Draft
= 8, No of doubling = 8,
Feed sliver wt
= 0.01 lb/Yd, Efficiency =
90%
Solution:
Draft= (Feed wt/Delivery
wt)* Doubling
So, Delivery wt= (Feed
wt/ Draft)* Doubling
So, Delivery wt=
(0.01/8)* 8 = 0.01
lb/yd
Production = 600 m/ min
= 600*1.09 yds/min =
654 yds/min
= 654*0.01 lbs/min =
6.54 lbs/min = 6.54*60*8
lbs/shift
= 3139.2 lbs/shift
For 90% efficiency and
no. of delivery, the
ultimate production is,
3139.2*0.9*2 = 5650.56
lb/shift (Ans)
38. Lap former
• Lap former is the machine where
lap is produced from slivers. It is
necessary for producing combed
yarn. Because the output of
comber machine is lap.
40. Comber
University
of
Dhaka
• Combing :
Combing may be defined as to
remove short fibers , neps and
remaining impurities of card sliver
by using comb with the help of
knives, brushes and rollers.
41. Objects of combing
• To remove short fibers below a
preselected length so that the
spinner enable to produce finer /
better yarn.
• To remove neps and foreign
matter from the cotton / sliver.
• Make the fiber straight and
parallel.
42. University of Dhaka
Blow room lap Comber lap
Short fiber high Short fibre low
Uniformity low Uniformity high
Trash high Trash low
Lap count .0011-.0019 Ne Lap count .0075 -.009
Lap wt /yds 12-16 ounce Lap wt /yds 1.6-2.5 ounce
Lap width 1m Lap width 300 mm
44. Combing Action
• Firstly, Sliver comes through feed
plate, After passing the edge, the
nipper comes down to clamp the
fiber between feed plate & itself.
Then the first combing is done by
the cylinder.
45. Combing Action
• Then, nipper moves upward. Sliver
feeding starts again. When sliver
comes to detaching roller, the
rollers give a backward movement
to join it with previously combed
sliver. That time Top comb comes
down and by the forwarding
movement of detaching roller,
second time combing is done by
top comb.
46. This process is a intermittent process. Because all these are
carried out up to 300 times per minute.
48. Speed frame
University of Dhaka
TASK OF RING FRAME: TO PRODUCE ROVING
FROM SLIVER.
TO IMPACT STRENGTH
TO THE FIBER BY
TWISTING.
TO WIND UP THE
RESULTING ROVING ON
TO ROVING BOBBIN.
50. Operation
involved in
Speed Frame
• Creeling: Sliver feeding with the help
of several rollers. 40 drawn slivers can
be creeled at a time.
• Drafting: To reduce wt per unit length
of roving in speed frame so that
produces roving can be converted
into yarn easily with draft in drafting
Zone. For this normally 3 pairs of
rollers are used.
University of Dhaka
51. Operation
involved in
Speed Frame
Twisting:
To insert small amount of twist to
get required strength of roving . so
that no breakage of yarn and
possible to wind of roving in
convenient package. Usually 30-65
turns per meter twist is given which
are created by flyer. But twist in
roving are given such that the fibers
hold its constituent fibers together
and not create hinder during
drafting in Ring frame.
University of Dhaka
52. Winding:
To wind the roving on to a
suitable bobbin which will help
handling , transfer and feeding
to ring frame. Due to winding ,
as dia of bobbin is gradually
increased, the speed of bobbin
is continuously decreased with
the help of building motion so
that no breakage of roving for
too much tension.
53. University of Dhaka
Building
Building : With the help of building
motion , the correct or proper shaped
package is made by winding of roving
on bobbin in some consequent process.
Doffing
Doffing : To replace empty bobbin at a
place of full bobbin.
56. Ring frame • Ring frame is the machine where yarn is
finally produced from the roving.
University of Dhaka
57. Function of
a Ring
frame:
University of Dhaka
To satisfy the roving to form yarn of
the required count/ fineness of yarn
by drafting & twisting.
To increase strength.
To build up the yarn on to bobbin in
form of a suitable package for
storage, transportation and
processing.
58. Operation
involved in
ring frame
University of Dhaka
Creeling
Roving bobbin is fitted on the top of the
m/c on the creel on both sides of the
m/c. creel helps to freely rotate of
roving bobbin and hold such that roving
feed to the drafting zone on tension.
60. • Drafting
• Drafting operation reduces wt per unit length of roving .
roving comes from the bobbin are passed through the
drafting.
• Twisting:
• Spiral turns are inserted along the fiber axis . It increases
yarn strength .The traveler which helps to insert twisting
yarn, gets drive indirectly from spindle.
University of Dhaka
61. Winding:
After twisting the yarns are wound
on a suitable package , layers of yarn
are wound properly are above
another on the package . It should
be suitable for unwinding
Building:
For proper size and shape of the
package the bobbins are lifted
gradually. The resultant bobbins are
conical shape full bobbin.
University of Dhaka
62. • Doffing:
• After the required length of yarn is
wound on the package , the m/c is
stopped . Doffing is the process of
replacing the full bobbin by an empty
bobbin.
University of Dhaka
63. Flow diagram of Ring
Frame
A= Roving bobbin.
B= Roving guide.
C= Drafting zone.
D= Balloon control ring.
E= Ring.
F= Traveler.
G= Yarn bobbin.
H= Gearing.
64. Traveler
• Traveler is the most tiny &
important part made by metal
through which yarn passes its way
from balloon control ring to the
yarn package. It has no drive of its
own. But it is dragged round by
the yarn. During its rotation it
produces twist.
67. Ring Yarn & Rotor Yarn
If there is a simplex machine in
the process of yarn
manufacturing, that is ring yarn.
And if there is no simplex or ring
frame, but a rotor spinning
machine which converts sliver to
yarn directly, the yarn
manufactured is a rotor yarn.
69. Y1 = Ring Yarn & Y2= Rotor Yarn
University of Dhaka
Editor's Notes
Are your classroom colors different than what you see in this template? That’s OK! Click on Design -> Variants (the down arrow) -> Pick the color scheme that works for you!
Feel free to change any “You will…” and “I will…” statements to ensure they align with your classroom procedures and rules!
