Chapter

1 Introductio
Flow chart of carded yarn production:
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 → Roving
/Speed Frame/Simplex
Roving → Ring Frame → Yarn

Flow chart of combed yarn production:

Input Process/ Machine Output
Bale management
↓
Fibre → 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

Flow chart of Rotor yarn:

Input Process/Machine Output
Bale management
↓
Fibre → Blow room → Lap
Lap → Carding m/c → Carded
 sliver
Carded → Draw frame → Drawn
sliver sliver
Drawn → Rotor spinning → Rotor yarn
sliver

Properties of cotton fibres considered by cotton spinners:

The following properties of cotton fibres are considered for
cotton spgn:
I) Fibre fineness: Fineness is one of the most
important parameter determining the yarn quality
characteristics. Fibre fineness influences the
number of fibres in the cross section of yarn.
The finer fibre The higher the number of fibre in yarn cross

Reduce the yarn irregularity.

The greater the total surface are available for inter fibre contact
to provide the necessary cohesion + less twist required.
Thirty fibres are needed at the minm in the yarn cross section
but there are usually over 100. One hundred is approximately
the lower limit for almost all new spinning process. This
indicates that fineness will become more important. Fibre
influences primarily:

 Spgn limit.
 Yarn strength.
 Yarn evenness.
 Yarn fullness.
2
 Drape of the fabric product.
 Luster.
 Handle.
 Productivity
Fineness is ,measured in Micronaire value(MIC)
The higher micronaire value the fibre regarded as coarser.
Rating of MIC value-

MIC Description
Less than 3.0 Very fine
3.0-3.6 Fine
3.7-4.7 Medium
4.8-5.4 Coarse
5.5-Above Very coarse

II) Maturity: The maturity of cotton is defined in terms of

the development of cell wall. A fully mature fibre
has a well developed thick cell wall. On the other
hand, an immature fibre has a very thin cell wall.
The fibre is to be considered as mature fibre when
the cell wall of the moisture-swollen fibre
represents 50-80% of the round cross section, as
immature when it represents 30-45% and as dead
when it represents less than 25%.

3
 N-D
Moisture Ratio=  0.7
200
If , M.R.=0.85, good fibre
M.R.=0.75, average fiber
M.R.=0.65, poor fibre
Immature fibre leads to:
 Nepping
 Loss of yarn strength.
 Varying dye ability.
 High proportion of short fibres.
 Processing difficulties mainly at the card
Mature fibre→ Dye absorb↑
Immature fibre→ Dye absorb↓
III) Fibre length: The average length of spinnable fibre is
called staple length. Staple length is also one of the most
important fibre characteristic. The quality, count, strength
etc. depend on the staple length of fibre.
Staple length↑→ Yarn quality↑
Fibre length influence:
 Spinning limit.
 Yarn strength.
 Yarn evenness.
 Handle of the product.
 Luster of the product.
 Yarn hairiness
 Productivity
Fibre length measure unit:
4
  Staple length.(inch)
 Effective length.(inch)
 2.5% span length.(inch)
 50% span length.(inch)
 UHL-Upper half length(mm)
UHML-Upper half mean length(mm)

The following length groupings are currently used in stating

the trade staple:
Short staple: 1″ or less.
1  1 
Medium staple: 1 to 1
32 8
 
Long staple: 1 5 to 1 3
32 8
13 
Extra long staple: 1 and above
32
IV) Length uniformity: Length uniformity influences
on:
 Yarn irregularity.
 Ends down.
 High wastage in combing.
 High fly liberation & m/c contamination in spgn,
wvg & knitting.
There are two popular measures of length uniformity in
a cotton sample:
i) Uniformity Ratioss(UR)
ii) Uniformity Index(UI)

5
 Defined as follows:
50% Span Length
UR  100%
2.5% Span Length
Mean Length
UI  100%
Upper half mean length
V) Strength: Toughness of fibre has a direct effect on
yarn & fabric strength.
Fibre strength↑→ Yarn & Fabric strength.↑
Very weak cottons tend to rupture during processing both
in blow room and carding, creating short fibres and
consequently deteriorate yarn strength and uniformity.
Minm strength for a textile fibre is approximately 6
CN/Tex (about 6 km breaking length)
Some significant breaking strength of fibres are:
Polyester : 35-60 CN/Tex
Cotton : 15-40 CN/Tex
Wool : 12-18 CN/Tex
In relation to cotton, the strength of fibre bundles is
measured and stated as the Pressley value.
Breaking load in lbs
The Pressley Index =
Bundle wt in mg
The following scale of value is used:
Below to 70 - Weak
70-74 - Fairly strong
75-80 - Medium strong
81-86 - Strong
87-92 - Very strong

6
 93 and above - Excellent value
VI) Fibre cleanness: In addition to usable fibres, cotton
stock contain foreign matter of various kinds:
Vegetable matter:
Husk portions
Seed fragments
Stem fragments
Leaf fragments
Wood fragments
Mineral material:
Earth
Sand, dust, coal
Other foreign matters:
Metal fragments
Cloth fragments
Packing materials
Foreign matter causes:
i) Drafting disturbance.
ii) Yarn breakage.
iii) Filling up of card clothing.
iv) Contaminated yarn.

Accepted the range of foreign materials to the Bale:

Up to 1.2% → Very clean
1.2% to 2.0% → Clean
2.0% to 4.0% → Medium
4.0% to 7.0% → Dirty
7.0% and Above → Very dirty
7
According to International Committee for Cotton Testing
methods the following types are to be distinguished:
Particle size(mm)
Trash Above 500
Dust 50-500
Micro dust 15-50
Breathable Below 15

VII) Colour: Colour is particularly important as a

measure of how well a yarn or fabric will dye or
bleach. Instrumental techniques for determining
the color of the sample have only now reached the
industry, HVI measurement of color provides
reasonably accurate results of average reflectance
and yellowness in a sample.

VIII) Fibre elongation: Elongation is specified as a

percentage of the starting length. The elastic
elongation is of decisive importance since textile
products without elasticity would hardly be
useable. They must be able to deform and also
return to shape. The fibre elongation should
therefore be at least 1-2% and preferably slightly
more.

8
 The greater crease-resistance of wool compared with
cotton arises for example from the difference in their
elongations cotton 6-10%, wool 25-45%

Contribution of fiber properties to yarn quality:

The impurities can lead the following disturbance during

processing:
i) Metal particles can damage card clothing & cause
fire.
ii) Cloth & packing mtl is fragments can lead foreign
matter in the yarn making unsuitable for the
application.
iii) Vegetable matter can lead to drafting disturbance,
yarn breaks, filling up of card clothing,
contaminated yarns etc.

Importance and effect of condition on fiber properties:

Standard atmosphere:
0
Temp:  20  2  C

9
Relative Humidity:  65  2  %
In tropical and subtropical countries:
RH:  65  2  %
0
Temp:  27  2  C
The samples are dried in a closed chamber using dry air for a
short time and then the samples are allowed to attain eqm with
the room air in a short time. An evaluation study by R.S.
Brown showed that rapid conditioning of lab sample is equal
to room conditioning is trays for 24 to 48 hrs.
HVI: HVI consists of modules that can be combination of the
following measuring modules:
 Length/ Strength module
 Micronaire module
 Color/ Trash module
 NIR module
The HVI 900 system is housed in two floor standing cabinets,
the larger cabinet contains the length/ strength module and
the smaller cabinet contains the micronaire, color/ Trash and
NIR module. Included with the system are an alphanumeric
keyboard, monitor and balance. As tests are completed for
each sample, the results can be transmitted to a printer and/
or and external computer system. The 900 system consists of
modules that can be combination of the following measuring
modules:
 Length/ Strength module
 Micronaire module
 Color/ Trash module
 NIR module.
10
Function of HVI:
HVI mean High Volume Instrument. This is a fibre testing
instrument. The USTER HVI 900 system measures fibre
strength, length, length uniformity, elongation, micronaire,
color and trash, NIR values of cotton fibres available on those
systems that have the optimal 950 NIR module.

SCI: Spgn consistency Index is a calculated value base in

multiple regression analysis comparing fibre properties to
yarn properties.
An eqn takes into account all High Volume Instrument
properties and calculates on value to be used on each sample
tested.
Currently the following eqns are used for SCI.
Uniformity Index (where UHML and ML in inches are used:
SCI = -412.7 + 2.9 strength – 9.32 Mic + 49.28 length + 4.80
Uniformity + 0.65 Rd
Uniformity Ratio (where 2.5% span length and 50% span
length in inches used):
SCI = -412.7 + 2.9 strength – 9.32 Mic + 49.28 length + 8.72
Uniformity + 0.65 Rd

Bale management: Testing, sorting & mixing bales according

to properties of fibre for producing specific good quality yarn
at minm cost is called “Bale management”.

Object of Bale management:

11
  An evening out of the quality characteristics of a yarn.
 A means of avoiding quality jumps.
 A possibility of reducing costs, as result of an
improved knowledge of the fibre characteristics.

Basics of bale management:

 Each individual bale contributes to the fibre blend and
to a large extent, the yarn properties.
 The final mix is only completed at the last passage of
drawing. To check the resulting fibre properties of a
mix is at the finisher sliver.
 The influence of the individual fibre properties of a
mix on the yarn properties in not fully-known.
 With the bale management the random uncontrolled
variation of the bale mix can be improved for this
reason the variation of each fibre characteristics in
every bale mix.

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, colour variation.

Procedure/ Step by step implementation of Bale

Management:
Before starting bale management, Textile Technologist have to
know the relation exist between fibre and yarn.
12
Step-1: Test 100% of Bales by HVI suppose the test results are
like as in the table.
Sl. no Bale No Mic SCI Color
1 1 4.0 100 12
2 2 4.1 105 22
3 3 4.5 109 21
- - - -
300 200 4.5 110 21
Step-2: Decide on which property we want to give special
emphasis. Suppose emphasis on MIC (growth of all bales
considered same). Then procedure a chart like below:
MIC/SCI 90-99 100-109 110-119 120-129
4 1 2 1
4.1 10 33 2
4.2 50 40 4 1
4.3 30 20 5
4.4 1 2 1
4.5 1 1 1
Step-3: It is better to take bales of similar category as close as
possible. For price production factor, suppose we are choosing
SCI (90-99), (100-109) and MIC 4.1, 4.2, 4.3
Step-4: Make a list according to category (named as A,B)
A B C D E F
SCI 90- 90- 90- 100- 100- 100-
99 99 109 109 109 109
MCI 4.1 4.2 4.3 4.1 4.2 4.3
Bale 1 10 7 21 1 -

13
No
2 20 15 24 - -
Total 10 50 30 33 40 20 183
Per 61
day
Consider daily required of bale is 61

Step-5: Stack or arrange bales to get homogeneous mixing.

F A B C D E F D
E
For Blendomat
D
C
B
A
D
For Stack Mixing
If a number of bales in a category is higher than 10 then it is
better to divide them in two and arrange them to get random
mixing.

Mixing & Blending

Mixing: If different grade of same fibres are kept together,

then it is called mixing.

14
 1  1 
e.g. 50% of 1 staple length of cotton + 50% of 1 staple
8 4
length of cotton.
Types of mixing:
i) Volume mixing
ii) Wt. mixing.
iii) Hand stock mixing.
iv) Bin mixing.
v) Mixing by hopper.
vi) Lap mixing.
vii) Card mixing.
viii) Sliver mixing.
ix) Automatic mixing.

Blending: When different fibres of same or different grades

are kept together, then it is called blending.

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, drape luster etc.
 To give the required characteristics to the end product.
 To achieve effects by carrying colour, fiber
characteristics and soon.

15
Process stage of blending Type: Types of Blending
operation:
Blending type Process stage
Bale mixing - Before the blow room
Flock mixing - Within the blow room
Lap ,, - Using doubling scutchers
Web ,, - At the ribbon lap m/c or
the blending draw frame
Sliver ,, - At the draw frame & sliver
Lap or the comber
Fibre ,, - At the card or Rotor spgn m/c
Roving ,, - At the ring spgn m/c

Blending procedure:
Blending is carried out in three stages:
Metering, determination and precise establishment of the
quantities of the individual components.
Mixing, that is bringing together of the metered quantities.
Interminling,distributing the components evenly in the body
of fibres.
Each stage is as important as the other. However, difficulties
arise primarily in intermingling and in maintaining the blend
once it has been achieved. The latter is very difficult with
fibres of different surface structure and varying energy-
absorbing capacity on stretching,because of de-blending tends
to occur at various processing stages.

Draw frame blending:

16
Advantages:
 It is easier to obtain blend ratio.
 Less damage of fibre.
 Easy working.

Disadvantages:
 Difficult to achieve random arrangement of fibre in
yarn cross section.
 Additional drawing capacity needed.
 Separate opening line needed for each component.
Blow room/ Lap blending:
Advantages:
 Ensure good blend homogeneously.
 Easy to work.
 Uniform blend ration obtained.

Disadvantages:
 The opening has to be modified.
 Need for proper control or lap wt.
 Can not be used when the properties of one component
is low.

Opening: Opening is needed for carrying out the basic

operations of spgn. The raw mtls enter the spgn mill in highly
pressed form to enable optimum transport and storage
conditions to be used. Thus opening must precede the basic
operations.

General factors influencing fibre opening & cleaning:

17
Raw mtl:
1. Thickness of feed mtl.
2. Density of feed mtl.
3. Fibre coherence.
4. Fibre alignment.
5. Size of flocks in feed
M/C or Device:
1. The type of opening device.
2. Speed of opening device.
3. Degree of penetration.
4. Spacing of the feed from opening device.
5. Type of grid.
6. Greed setting.
7. Air flow through feed.
8. Condition of pre-opening.
9. Position of the m/c in Blow room line.
Problem-01: MIC = 4.5, Strength = 70 gm/Tex, Length = 30
mm, UR = 45, Rd= 78.8, SCI = ?
Soln:
SCI  - 412.7  2.9  Strength
- 9.32  MIC  49.28  length  8.72 UR  0.65  Rd
 - 412.7  2.9  20 - 9.32  4.5
49.28 1.18  8.72  45  0.65  78.8
 105.1304

Ginning:
The freshly picked cotton has seeds in it, this cotton is called
seed cotton. The treading is done in this condition also, but
normally the treading is done after separation of the fibres

18
from their seed. So, the process, involves to separate the cotton
fibres from seeds is called ginning.

Objects of ginning:
 To separate fibres fully from its seeds.
 To collect seeds and waste together.
 To collect fibre without any faults.
 To separate whole fibre.
Types of ginning: –
1. Saw ginning
2. Roller ginning
3. Macarthy ginning
Faults in ginning:
 Gin-cut fibre
 Crushed seeds
 Nep formation
 Too much wastage

Chapter

2 Blow
Room
Blow Room: Blow Room 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.
Blow Room Section:

19
A section in which the supplied compressed bales are opened,
cleaned and blending or mixing to form uniforms lap of
specific length is called Blow Room section. The cleaning
efficiency of blow room is 60 to 65%. This is the first section of
spinning line for spgn wt cotton yarn.
Operation in Blow Room:
I. Opening:
a. To open the compressed bales of fibers
&
b. To make the cotton tuft a small size as for as
possible.
II. Cleaning: To remove the dirt, dust, broken seeds broken
leafs, stalks and another foreign materials from the fibers.
III. Bending or Mixing: To make good value of yarn and to
decrease the production cost by mixing different grade of
fibers.
IV.Lap forming:
a. To transfer the opened and cleaned fibers into
a sheet form of definite width and uniform unit
length which is called lap.

b. To roll the lap of predetermined length in a

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 subsequence processing
carding m/c.
20
Action in blow room:
The actions of the machines in any blow room range fall into
one or more of four main groups namely:
1. Action of opposite spike: (opening)
The action of opposite spikes is opening the cotton fiber. By
this action, the large pieces of cottons have been reduced in
size.

2. Action of Air current: (Transport + Cleaning)

During processing, the movement of cotton from machines to
machine is done by air current. It also helps the separation of
lint and trash.

3. Action of Beaters: (Cleaning & Opening)

Beaters are responsible for removing almost all of the impurity
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 of
cotton fiber by the help of swing door and swing paddle

 Electrical photocell
 Air pressure syatem

Basic operations in Blow Room:

1. Opening: Opening is the 1st operation required, carried
out to the stage of flocks in the blow Room and to the stage of
21
individual fibers in the Card.
%

Function of raw mtl (%) 

Flock weight can be reduced 100
to about 0.1 mg in the Blow
Room.
2. Cleaning: A blow 50
Room Installation removes
approx. 40-70% of the
impurities. The result is
0 5 10
dependent on raw materials, Function of dirt (%) 
on the machines and on the environment conditions. From the
graph, cleaning effect cannot and should not be the same for
all impurity level, since a lot of dirt can be removed more
easily than a little. In order to clean, it is necessary to eliminate
about as much fiber as foreign materials.
Percentage of total material eliminated, in cleaning efficiency
%.
AT  AE
CE   100
AT
Totsl waste - Good fibre eliminated

Total waste
3) Blending: Fibers can be blended at various stages of the
process. These possibilities should always be exploited.
Example- transverse doubling. The start of the process is one
of the most important stages for blending. Intensive blending
in a suitable blending m/c must be carried out after separate
flock extraction from individual bales of layout. This blending

22
operation must collect the sequentially arriving bunches of
fibres from individual bales and mixes them thoroughly.
4) Dust Removal: Almost all manufacturers of blow
room machinery now offer dust removing machines or
equipments in addition to opening and cleaning. Dust
removal is not an easy operation, since dust particles are
completely enclosed in the flock and hence held back during
suction.
Dust removal (%) 

30 I
II a
20 b

10

1 2 3 4 5 6 7
Various processing stages 

Fig: Dust removal as a percentage of the dust content of the raw cotton at the
various pressing stages.
1-5 Blowroom m/cs, 6 Card, 7 Draw frames I+II, a filter, b Taker
in; I  Dust in the waster, II  Dust in the exhaust air

Beaters Used in Blow Room Machine:

1.Porcupine:
Function:

23
  Good opening beater
 Considered most suitable for long
staple cotton.
 The striker are arranged at different
angles to cover the total width of the
m/c in one revolution of the beater.
 Revolution per minute of Beater 750-960.
 To separate the fibers by striker.
 To clean the fibers

2. Bladed beater: Beater arms(Multiple bladed beater)

 The beater bars arranged parallel to the supporting

shaft and held by four or five cast-iron arms.
 Opening an cleaning effect is small.
 It is hardly found row, it is only in the form of the
double beater scutcher.
 Multiple bladed beaters are two types:
1) Two bladed beater
2) Three bladed beater.
1. Two bladed beater:

24
  Two blades are arranged in both sides and
equal distance of shaft.

 Revolution per minute 800-850.

 To clean broken seeds or heavy impurities of
fibers.

2. Three bladed beaters:

 Similar to two bladed beater
 Three blades arranged in equal distance of shaft

 Clean darts like two bladed beater but are more

effective
 RPM of three blades beater 850-940.
25
3. Kirschner beater or beater with pinned bars:
 It consists of three-armed “Spiders” mounted on a shaft ,
well-pointed, steel pins arranged in staggered formation
to ensure adequate combing of cotton.
 Efficient cleaner.

 Exclusively used for MMF Production.

 RPM of K. B is 750-850.
 To change cleaning efficiency due to changes setting of
Beaters and grid bars.

Objects:
i) To convert into / to make the cotton tuft a small size as
for as possible by opening when.
ii) To clean all kinds of dusts.
iii) To delivery of balanced layers of fibers by beaten
feeding.

Rollers used in Blow room:

26
1. Spiked Roller / Roles with teeth or blades or Spikes:
 Flat, oval or round bars are welded, riveted or screwed
to closed cylinders.
 Used in Modern Horizontal Cleaners, Chute feeds,
Mixing bale opener, step cleaner etc.
 At the start of the blow room line, the spacing of the
striker elements on the roller is greater & finer spacing is
used in the middle of line.
 The rollers rotate at speeds in the range 600-1000 rpm.
 Bladed drum is used in Porcupine opener.

2. Drums with teeth or spikes:

 Same as rollers but larger diameters of 600 mm and
more.
 When the drum is designed for use at the start of the
process, the spacing of the
striker elements on the
drums is coarse.
 and fine when the drum is
designed for use in the

27
 middle or towards the end of the line (for example
porcupine cleaner)
 Rotates vary between 400-800 rpm
 Parallel, on right angled arrange the device to the
material flow.

3.Rollers with toothed discs:

 It is made up of many toothed discs secured to a shaft

with an appropriate number of distance pieces.
 The teeth are almost always asymmetrically formed
since they have to operate in only one direction.
 Rollers with toothed discs belong to the middle of the
blow room line.
4. Carding roller:

28
  Saw-toothed wire is used.
 Gives first opening and best cleaning action
 But creates stress on fibers.

 Rotational speeds lie between 600 to 1000 rpm

 Carding roller is used at the end of blow room line.

5. Rollers with pinned bars/ kirschner roller:

 Simple in design
 Gives favorable flow of fibers
 Operates like kirschner beaters.

29
Elements/ Types of grid:-
The following element can be used in the grid:-
1) Slotted sheets & 2) perforated sheets:
Function: Both are formerly placed under cards and used
to a steadily decreasing extent.
3) Triangular section bars:
Modern grids are mostly made up of triangular bars.
Function: These are robust east to manipulate and give a
good cleaning effect.

4) Angle bars:
Function: These are somewhat less robust and can tend to
create blockages.
5) Blades:

30
 Today; grid are made up of knife blade alone, without
other element types.
Function: Blades have been used as grid elements for a
long time, almost always in combination with triangular
section bars.

Grid adjustment:
I) The grid can be one, two or
three parts.
II) It can be adjusted only as a
unit or in individual
settings.
There are Three Basic
Adjustments:
Distance of the complete grid to
the Beater grid.
a) Closed:
b) Open:
Setting angle Relation to the Beater Envelope
c) Glacing –similar to open type.
d) Aggressive

Faults in Blow Room: Following common defects may occur

to the lap in Blow Room:
1. Uneven lap: Patchy, sticky, thick & thin places in lap.
Causes:
31
  Uneven feed of material.
 Faulty regulating motion.
 Improper m/c maintenance.
Remedies:
 To ensure even feed of material.
 Correct bale opening.
 Proper m/c maintenance.
2.Irregular lap: Lap should be of definite shape, length & wt/
unit length. If the lap length is less than the required length
then it is call Irregular lap.
Causes:
 Uneven feed of fibers to feed lattice.
 Presence of weak, small and immature fibers in fibers
during mixing.
 Faulty regulating motion, cage, swing door
 Improper m/c maintenance.
3.Soft lap: If the lap is less compact, it is called softly.
Causes:
 Low pressure of calendar roller.
 Less relative humidity.
 More trash content of fiber.
Remedies:
 Relative humidity should be conrolled.
32
  Pressure of calendar roller should be controlled.
 Cleaning should be correct.
4.Conical lap: If the width of lap increases or decreases with
respect to its initial width, the lap is said to be “Conical
lap”.
Causes:
 Air suction varies due to fan speed variation. So uneven
drawn of material at both sides of cage.
 Pressure variation at both sides of calendar roller.
 Dirt drain in one side of cage.
 More air Intel at one side.
Remedies:
 To ensure proper airflow.
 Calendar roller pressure must be controlled
 After a certain time, cage must be cleaned.
5. Barrel shaped lap: If the thickness of lap in middle is more
than that of at the border sides it is called Barrel shape lap.
Causes:
 More air suction in the middle position of the cage due
to excessive fan speed and so more fiber is drawn in the
middle position.
 Due to accumulation of dirt at both sides of the cage.
Remedies:

33
  Fan speed should be controlled.
 After certain time cage must be cleaned.
6.Licking lap:
Causes:
 Low pressure of calenderer roller.
 Excessive fan speed
 Improper Roller motion setting
 Low opening of cotton.
 Used soft waste at greatest rate with general cotton.
Remedies:
 Proper fan speed.
 Proper pressure of calendar roller
 Proper opening of cotton.
 Correct fan speed.
7.Defective selvedge: Both sides of lap are uneven
Causes:
 Waste accumulation at m/c sides
 Waste accumulation at grid bars and cage sides
 Broken gear teeth or m/c parts.
 Faulty cage and faulty surface of lattice.
Remedies: proper maintenance of cage and lattice.
8.Split lap: The cotton splits into sheet like a sandwich when
unrolling at the card.
Causes:
 Low pressure of calendar roller

34
  Low temp in Blow room section
 Variation of surface speed of Top and Bottom cage
Remedies:
 Proper pressure of calendar roller.
 Proper temp
9.Dirty lap:
Causes:
 In sufficient dirt removal
 Dirty m/c due to improper maintenance.

Faults due to cage:

i) Defective selvedge
ii) Conical lap
iii) Split lap
iv) Barrel shaped lap
Standard Lap specification: (approximate)
Lap length – ---------60 yds
Lap weight –-------- 40 – 50 lbs
Lap wt/yd – --------12 to 16 oz.
Lap wt variation – 3% (acceptable)
Hank – --------------0.11 – 0.19 Ne
Mechanical draft – 2.67 (approax.)

35
 Causes of lap wt variation/Desired characteristics of lap:
1. Unsuitable feeding:
i) Irregular feeding of fibers to the feed lattice by the
feeders in the bale opener.
ii) Feed of very large piece of baled cotton.
2. Characteristics of fiber in blend:
i) If the blend contains improper mixing of fiber it may be
varying fineness.
ii) If there are immature fibers in the blend, produce lap
irregularity.
iii) If there are weak and short fibers, produce irregular lap.

3.Incorrect setting of different m/c parts:

i) Mechanical swing door or photoelectric cell: Lap
variation will produce due to setting faults in this
instrument.
ii) Setting of evener roller: If the setting is incorrect, the
opening regularity of flow of fiber and rate of
production of the m/c is affected with causes lap
irregularity.
iii) Piano or cone drum regulating arrangement:
If the system dies not work effectively, causes lap
variation.
4.Improper maintenance of the machinery:

36
 Due to not well maintained proper opening. Beating
and cleaning, disposal of dust, control of air current,
fan speed etc. leads too lap variation.
5. Excessive waste content in lap:
6. Incorrect fan speed: If fan speed is to slow, the fibers
move on the cages. On the other hand ,if the air flow is
to strong, the cotton is drawn down – wards the centre
of the cages and will give a barrel shaped lap.
Different type of feed apparatus:
I) Feed with two cooperating clamping rollers/ cylinders:
+ ve - It gives better forwarding
-ve – but greatest clamping distance between the roller and
beater.

II) Feed with roller & table:

(-) Clamping over the whole width is poor since the roller
presses only on the highest of the web. So thin places
in the web can be dragged out of the web.
(+) Clamping distance can be made very small gives
intensive opening of fiber.
37
III) Feed with roller and pedals:
(+) The table against the roller divided into many
sections and can be pressed individually on the web
against the roller.
(+) This gives secure clamping with a small clamping
distance.

Blow room installation: In order to perform their assigned

tasks optiomally, these m/c must be located at quite specific
positions in the Blow room line. In a normal modern blow
room installation, six clearly distinguishable operating zones
can be identified.
1. Zone-1 (Opening)
38
2. Zone-2 (Coarse cleaning)
3. Zone-3 (Blending)
4. Zone-4 (Fire cleaning)
5. Zone-5(Intensive cleaning)
6. Zone-6(Card feeding)
1) Zone-1 (Opening) Blendomat: This type of m/c is most
widely used. It enables processing up to 70 bales
arranged as four components per blend and process
one or two blend simultaneously.
2) Securomat: Zone – 2 (Coarse cleaning): Two things are
conspicuous in coarse cleaning machines.
They generally process the materials while it is in free
flight. The striker elements are widely spaced on the
operating Rollers. Coarse opening machines are
optimal at their given position in the line but not at
other position.
3) Multimixer: Zone 3 (Blending): the m/c comprises
several (6-8) adjacent chute chambers into which the
materials is blown from above. The chutes are filled
successively and material is removed from all chute
chambers simultaneously. This gives a good long-term
blend. Ejection of flocks on to a collecting conveyor is
performed by take-off and beating rollers under the
chute. The filling height is held fairly constant by
feelers.
4) Zone – 4 (Fine cleaning): CVT3
39
 Machines always operate with clamp feeds. Also the
spacing of the striker elements on the rollers must be
finer. Bladed rollers are generally used the well-
known horizontal cleaner fitted with rollers instead of
drums.
5). Zone – 5 (Intensive cleaning) Dustex
This zone was provided by the scutcher in the form of
kirschner beater and still may be even in Modern lines
with scutcher. In addition to the Kirschner beater, there
may be a saw tooth roller.
Where only one machine is used, the carding Roller is
preferred to the kirsehner beater.
6) Zone – 6 (Card Feeding): His enormously important
that the Coref receive feed Mtl that itself is
homogeneous uniform from card to card and remains
const over a long period.

6 6 6 6 6 6

2 3 4 5

1. Blendomat
2. Securomat Sc
3. Multimixer
1 4. Cleaner CVT3
5. Dustex
6. Card
7. Fan

40
Zone-1 machines ‘Opening’:
1. Automatic bale opening machines:
 The first generation automatic bale opener machines
were mostly stationary.
 Only the bale moves either backwards and forwards or
in a circle.
The second-generation machines are of traveling type:
 They move past the bales of the layout
 Extract materials from top to bottom
 More bales can be processed as an overall unit
 As a result long term blending is achieved
 A bale layout can comprise up to 60 bales from 4 to 6
different origins.
Properties required for the machines of the first zone could be
able to:
 Extract materials evenly from the bales
 Open the materials gently.
 Open up to the smallest flocks.
 Form flocks of equal size.
 Process as many bales as possible in a single charge
 Be universally applicable i.e. easy to program.
 Blend material right at the start of the process.
 Process putting together of a fiber blend from several
components.
41
2. Schubert & Salzer Blending Grab m/c:
 One of the first traveling m/c with stationary bales.
 It can process up to six bale groups of different bales
height per blend.
 Any number of bales can be included in the layout and
maximum production rate is 600 kg/hr

Fig:Schubert and salzer blending grab

 The m/c operates with spring grab, which is pivot able

through 900.
 The quantity of fibers grasped is mainly dependent
upon the width of opening of the grab.
 The grab moves upwards with the grasped material and
open into a weighing container.
 The whole carriage moves to the next bale and starts a
new grasping cycle.

42
  When the pre-programmed weight of one component
has been loaded into the weighing container, the
carriage moves on to the second component.
 When the weighing container has received the present
quantity of material from each component, the carriage
travels to the end of its path and throws the materials
onto the conveyor of blending opener.
Unifloc of Reiter:
 It enables processing of up to 70 bales arranged as four
components per blend over a maximum layout length of
41.5 m.

 The m/c can process one blend or two blends

simultaneously.
 The prodn rate is normally up to 750 kg/hr.

43
  The feed duct and two guide rails are secured to the
flour.
 The chassis carries a turret which is rotable through 1800
and supports a raisable and lower able extracting
assembly.
 To right and left of the extracting roller there are
retaining rollers that permit remnant-free extraction of
material even from the last layers of the bales.
 The bales are laid out to left and right of the m/c and
bales can be processed from both sides simultaneously
into one blend or from one side only.
 New bales can be prepared on one side and left to
acclimatize while other bales are processed on the other
side.
 A micro processor is provided for fully automatic
extraction of material from the bales.
The Unimix of Rieter:
 The machine is made up of three parts; a storage
section, and intermediate chamber and a delivery
section.
 Flocks are feed pneumatically and simultaneously
into six chutes(2) which arrange behind one another is
the storage section.
 A conveyor belt(3) leads the stock of materials through
the intermediate chamber to take-off unit.
 The column of materials thus diverted out from
vertical to horizontal.

44
  In addition to a condensing, this 900 bend in the
material flow, produces a shift in timing and special
distribution of fibre packet from 1st chute to last chute.
This in turn results in long-term blend.
 There-after, the material extracted from the
intermediate chamber and subjected to next step
between the spike lattice (5) and evener roller (7).
 An optical sensor ensures that, small amount of fiber
to hold in mixing chamber (6). After the spike lattice
there is either, a simple pneumatic suction feed to the
next machine or cleaning unit.
Step cleaner: Ultra cleaner:
Object:
 To open and clean cotton tuft by opposite spikes and
beating action.
 To remove heavy impurities such as leaves, sand
without damaging the fiber.
45
  To make/ covert the cotton tuft to small size of cotton
fibre.
Basic function: Opening and cleaning are lead by the
following two actions:
1. Action of opposite spikes
2. Action of Beater.
M/C parts: 1. Feed Roller 2. Six Beaters
3. Baffle plate 4. Grid bar

Working principle:
 The cotton or materials falls into the feed hopper.
 Passes to the first beater.
 Then it is transported upwards by the six beater rollers,
each carrying profiled bars and the beaters are arranged
on a line inclined upwards at 450.

46
  The trashes are extracted by the help of opposite spike
and beating function extracts the trashes and falls into
the chamber through grid bars hole.
 Cotton tuft open and make small size tuft with beating
action.
 A buckle is in the middle of per two beaters and it
control flow of material.

Dual roller cleaner/Axi-flow cleaner(AFC):

1) Inlet pipe
2) Beater Roller
3) Deflecter plate
4) Grids
5) Guide plate
6) Bucket Wheel lock
7) Outlet pipe

47
M/C Specification:
1) It has a large cleaning chamber
II) Contains two drums of 610 mm dia rotating in the
same direction.
III) There is a fan/ Bucket wheel down stream from the
dual Roller cleaner, draws material through the m/c by
suction.
IV) The exit opening is arranged at a higher level than the
infeed opening.
V) The spikes are arranged in a spiral order on the drums
in order to improve the passage of the material.
Working principle:
I) The condenser which follows in the line sucks the tuft
through the initial pipe into the large cleaning chamber
of AFC where the suction force decreases.
II) The outlet pipe is located at a higher level than the inlet
opening. So the suction stream is only able to carry
small tufts, which are already sufficiently opened and
cleared.
III) Thus the fiber leaves the AFC quickly without
undergoing any beating action.
IV) Fibers contained in large tufts fed once or more over
the grid bars before they leave the m/c.

48
V) They remain in the sufficiently long time to be opened
into small tufts, which releases their impurities easily.
Zone -3:
Multimixer m/c:
I) The machine comprises several (6-8) adjacent chute
chambers into which the material is blown from above.
II) The chutes are filled successively and materials are
removed from all chute chambers simultaneously.

III) This gives a good and long-term blend

IV) Ejection of flocks on to a collecting conveyor is
performed by` take off` and beating rollers under the
chutes.
V) The filling height is held fairly constant by feelers.

49
Zone – 4: (Fine cleaning)
RN Cleaner of Trutzcher: Dust removal m/c:
 The material passes in this example from a m/c of zone
2 (step cleaner) to the filling chute as the R-N cleaner
 Two Feed rollers are followed by the bladed rollers.
 The striker blades of Bladed roller are made up of metal
sheet and have double, hardened working edges. The
dia of the envelope of the beater is 1500 mm.

Step Cleaner

Bladed
roller

Grid Bar

 Half of this envelope is defined by a two-part grid

having in total 36 profiled sheet bars.
 The two grid bars are adjustable independently of each
others.
 Raw material passes with feed roller and is strike with
striker.
 Raw material is delivered towards up of the grid with
airflow after passing with grid bar.
50
  Dust is removed from raw material while passing on
Grid bar.

Single chute system:

 Feed of locks from the blow room(i) to the krischner
beater(8) is carried out by means of suction cage(2),
feed chute(3) and feed roller(7).
 Suction duct(10) takes the flocks away to the ring duct
of the cards. Excess materials is returned to the suction
duct by the way of return duct(11) and second chute(4)
and the krischner beater.
 Five to eight ends are
connected to the ring
duct, arranges in
longitudinal
direction.
 A fan blows the flocks
from the flock feeder.
 A pneumatic delivery
head is provided
above the card feed
chute.
 Then the flock enters
to the delivery, then it
decelerated and
adjustable nose
guides the flow of air

51
 and stream of fibre under the influence of gravity the
flocks filled the chute of cards by the leakage of air.
 Even filling of chute is obtained by adjusting the nose.

Double chute system/ Trutzcher chute feed:

 In a chute system, raw material is entered into the m/c
by the transport duct which extends overall machines
and then enters into the “Reserve Chute” of individual
card m/c.
 The transport air escapes form the Reserve chute via
comb is carried out by a “Suction duct”. The upper half
is a “Reserve Chamber” that receives the material from
the blow Room and separates the material from air.
 In this chute and “electronic pressure regulator”
ensures an approximately const height of material by
controlling the adjustable door.

52
 The feed roller pushes the stock into the region of
opening roller which plucks out fine flocks and ejects
them into the actual chute feed
 Controlled condensing of feed material is also carried
out by in feed of pressure air from a fan. Combs
provide in the chute permits the air to escape it, then
flock flows back to the fan.
 The air-stream in the chute, continuously leads the
flocks to the region in which the combs are covered by

53
 fiber. Thus an even distribution of flocks even the
whole chute width is obtained.
Auxiliary equipments:/Associated Equipments:
1. Metal Extractor /Heavy particle separator
2. Fire eliminator
3. Waste disposal

1. Metal Extractor /Heavy particle separator

1) Magnetic metal extractor:
 The knee-band extractors have permanent magnet at
the two impact surfaces.
 When flocks are driven against the magnets, ferrous
particles are retained and can be removed from time to
time.

 Magnetic extractors provide only a partial solution to

the problem because they can eliminate only
magnetizable metal particles and they let all others
pass.
 Electronic extractors are needed to remove the other
particles.
54
II). Electronic metal extractors:
 Electronic extractor automatically separates metal
particles of every kind and size i.e. magnetic or non-
magnetic.
 A metal detector is located in the transport ducting.
The sensitivity of the defector is adjustable.

 An eliminating arrangement is provided about 15 m

after this detector.
 When a piece of metal of any kind passes through the
detector,the entry and exit flaps are set so that the mtl
can not fly straight through the duct but must through
the eliminator.

55
  The grid holds the raw mtl and metal back while the
air can flow through the flow immediately return to
the normal flow condition.
 The floor of the collector chamber opens and the
contents fall into a transport container.

(2) Fire Detector & Separator:

Occurrence of fire: due to
 Friction
 Heat
 Formation of static electricity

 This comprises a spark detector and an eliminating

device and is built into the transport duct.
 The spark detector pivots the rapidly operating flap as
soon as the latter detects sparks or burning material.
 The material passes into a receiving container, which
preferably stands in the open air.

56
  Simultaneously, an alarm is given and the blow room
line is switched off.
 The pivoting flap remains in the eliminating condition
until the line is switched on again.

(3). Waste disposal:

The various processes in the blow room create various
was to mtls which can not be reused for textile purpose such
as:
 Coarse dirt remaining after recycling.
 Fly from the fire filters.
 Dust from the fire filters.
These waste mlts are preferably collected, baled, packed, and
removed so that hard ling is excluded as for as possible.
57
Modern Blow Room line for American Pima Cotton/ Cotton
3% Trash (CVT1):
Blendomat

Heavy material Separator

Multiple Mixture

CVT1 (fine)/ CVT3 (Coarse)

Dustex

Feeding unit (Chute Feed) for Card.

Modern Blow Room for American Upland cotton or cotton

containing more than 3% trash:
Blendomat

Heavy material separator

Multiple Mixture

Dustex

Feeding Unit (Chute feed) for Card
Blow Room Line for Low grade cotton:

58
Blendomat BDT or bale Opener BOB (Low or medium Grade)

Condenser LVSA

Blending Hopper BOBS

Axi flow Clearer AFC

Fan

RN Cleaner

Fan

Multi Mixer-8

Cleaning RST (Saw teeth Roller)

Dedusting M/C

Fan

Tuft Feeder for Carding
59
Blow room line for For high grade:
Blendomat BDT or bale Opener BOB (Low or medium Grade)

Condenser LVSA

Blending Hopper BOBS

Axi flow Clearer AFC

Fan

RN Cleaner
↓
Mutimixer – 10

Step cleaner

Kirchner roller

Dedusting machine

Fan
60
 
Tuft Feeder for carding

Regulating Motion:
Regulating action is responsible for maintaining a constant
flow of cotton through each m/c and controlling over the
regularity of the material through out the whole process. The
correct amount of cotton in the reserve box may be maintained
by the use of
 Swing door
 Photoelectric cell
 Measuring pressure
 Piano feed regulating system

Importance of regulating motion:

 To produce not only uniformed lap but also uniformed
sliver.
 This motion is important in the Blow Room in order to
maintain a const flow of cotton.
 For uniform feeding
 To remove dust, dirt and short fibers as required, this
motions needed.
 To maintain the desired characteristics of lap.

61
  To get optimum efficiency of machine in the Blow
Room.

Regulating action present in Modern Blow Room:

The following regulating action is present in Modern Blow
Room –
1. By photoelectric cell
2. By piano feed regulating system
3. By Air pressure.
4. By swing door
1.By photoelectric cell: Here the light source and photocell are
fitted opposite a window in each side of the m/c so that the
light passes through on to the m/c. While filling the cotton if
the light is broken between light source and photocell, the feed
of cotton is stopped until cotton again moves away from the
light source.
2. By Piano Feed Regulating systems:
Object:
 To feed the layer/wave of fiber uniformly to switcher.
 To control feed by decreasing the speed of feed roller
incase of thick places of cotton and by increasing the
thin places.
 To produce uniform lap.
Principle: The pedal movement caused by the thick and thin
places of cotton is employed to shift the belt in the cone drums

62
by means of lever to alter the speed of the feed roller in order
to keep the feed constains per unit time.
Description:
 16-18 Pedal levers are places side by side across the
width of the machine and mounted on a knife-edge rail
to avoid friction.
 The variation in thickness of cotton at feed point is
multiplied 5 to 6 times at the tail end of the lever,
which is usually in the form of a hook.
 Pendent links are provided on the hooked end of the
each system.
 The pedal ends are linked up in sets of three to suitable
tripod levers, which in turns are connected in pairs by
simple levers down to the bottom long levers and then
it is connected to the belt fork mechanism in the cone
drum box.
3. By Air pressure: When air and cotton are fed ,air is sucked
by another portion. This air pressure is measured by sensor
and is used to determine the amount of cotton present in the
Hoppers. If pressure is more, it stops feeding and if less, it
allows more cotton to enter.
4. By swing door : The arrangement of swing door is such that
when the hopper is about 2/3 to ¾ full of cotton, it is forced
down against the resistance of the counter balance spring, then
the drive to feed lattice is stopped.

63
The swing door is used for the uniform feeding of cotton to
spiked lattice.
Recent development of blow room line:
1. Improved or Input actions on blendomat slash
Uniform.
2. Optiscan
3. Electronic slash computer based system for
each m/c
4. Different new machine like CVT1, CVT3 etc.
5. Better cleaning efficiency of special type of
cylindrical saw toothed beater.
6. Better waste suction and management system.
7. Improved safety device.
8. Centralized computer control system.

Lap Length / motion: After a lap doffing, till a complete lap

formed such length lap is prepared, is called lap length. The
length of lap is kept to definite by the motion, which is called
lap length motion. Knock off motion is defined as the being
stopped the m/c automatically after produce a complete lap.
Lap length mechanism of Scutcher/ Lap forming unit:
Lap length is one control point in the spinning system in
which the scutchers operate. A special mechanical device is
built into the scutcher to achieve const length of lap.
Different machinery makers use different devices such as –
64
1. The knock off mechanism.
2. The hunter Cog mechanism.
1. The knock off mechanism:
The basic principle is the passage of cotton through the
calendar rollers make the cotton as a sheet due to pressure of
the heavy calendar rollers. If the calendar rollers stop but the
fluted shell rollers continue to rotate, the sheet of cotton will
break and the tail will wrap on to the lap, so that a full lap is
thus completed.

2. The Hunter Cog mechanism: On the end of the third

calendar Roller a gear wheel is keyed and this meshes into
another wheel, whose bearing is an lever capable of side ways
movement. In the fig. Wheel (b) is on the third calendar roller
and gears into wheel (c) mounted on the lever(d) Cog (e and
f) only come in contact after a certain revolutions or the
calendar roller when contact is made the notched cog (e)
pushes the cog (f) outwards. The result, which can be followed

65
in fig. is to release the drop lever and permit it to drop so that
the drive to the calendar roller is disengaged.

Scutcher machine:
Object:
 To produce a uniform lap.
 To open the cotton further to the smallest possible tuft
size.
 To extract as per as possible the remainder of the trash
left in the cotton.
Basic function: Beating action.
Working Principle:
 At first cotton is conveyed by a feed lattice from the
hopper feeder-1. ,Porcupine opener and Hopper feeder
– 2.

66
  Then it is brought into contact with three-bladed beater
(krichner beater). It accomplishes a very effective
opening and cleaning operation.
 From the beater chamber cotton passes with the air
stream to the cage and perforated cage.
 By the help of drawing roller cotton passes to calendar
Roller. Calendar Roller reduces the thickness of the
fiber.
 From the calendar roller, cotton is passed to lap roller.
The thickness of the fiber in lap roller is half inch.
Thus we get cotton in lap form by this scutcher m/c

Function of Air current:

1. Transport of foreign material.
2. Cleaning of foreign material.
3. To separate foreign material.

Types of Air Current:

1. Air cleaner.
2. Heavy material separator.

1. Air cleaner:
Object: To separate the particles which are mixed with cotton.
Working principle: It is an ordinary m/c. At first air, cotton of
trash is entered to a specific way. Then due to air cleaning
cotton with air goes to the upward direction & heavy trashes
67
fall down. Thus cotton is separated from heavy trash by air
cleaner.

2. Heavy material separator

68
 Mathematical Problem

Problem-01: Find out Beats/inch from the following

Beater rpm → 720
No of striker → 16
Feed roller rpm → 24
Dia of feed roller → 3"

Solution:
Beats/min = Beater rpm × No of beater
= 720 × 16
Surface speed of feed roller =  ×3×24
720x16
Beats per inch 
 x3x24
 76.43 76

Problem-02: The trash content of a cotton as fed to Beater

3.6%. The waste extraction is 1.5% of which 80% is trash. What
is the cleaning efficiency ?
Solution:
Of the 1.5% waste extraction,
80
Trash = 1.5  1.2% . Of the original trash has been taken
100
out by beater.
3.6 – 1.2 = 2.4% remains in the mtl delivered from the beater.

69
Cleaning efficiency =
Original trash content- Trash content in the delivered cotton
100
Original trash content

3.6  2.4
=
3.6
= 33.3% Answer

Problem-03: Find the Blow Room cleaning effy :

Raw cotton = 6%
Sliver = 6%
Cardin ding cleaning effy = 75%
Raw cotton Trash
Clearing effy = 100
Raw cotton
x  0.4
75 = 100
x
x=1.6
6  1.6
Blow room cleaning = 100
6
= 73%
Problem-04: Prodn of Blow Porn line with 2 Scutchers if
Calendar roller dia = 7˝
Calendar roller ppm = 10
Effy = 40%
Wastes = 4%
Lap wt = 1403/yd

70
 14
 10  7  60  0.90  x (100  4) x 2
Prodn of m/c = 16
36 100
= 555.176 lb/hr

Chapter

3 Carding
Carding: Heart of Spg :
Carding may be defined as the reduction of an entangled
mass of fibres to a filmy web by working bet n two closely
spaced, relatively moving surface clothed with sharp wire
points. The carding is the heart of the spg n mill & well
carded is half-spun-demonstrate the immense significance
of carding for the final result of the spg n operation. The
importance of carding is still greater where new spg n
systems are concerned.

Object:/ function:/ Task of carding:

1. Opening to individual fibers : The blow room only
opens the raw material to flocks where as the card
opens it to the stage of individual fibres. This
enables the elimination of impurities and good
performance of the other operation.

71
2. Elimination of Impurities and dust: Elimination of
foreign matter occurs mainly in the region of the
taker in. In addition to free dust, which can be
directly sucked away as in the blow room, the card
also removes a large proportion of the micro
particles. The card is a good dust removing m/c.
3. Disentangling of neps: The card reduces the no of
neps from the blow room. Actually neps are not
eliminated at the card, they are mostly opened out.
An improvement in disentangling of neps is
obtained by: closer spacing between the clothing;
sharper clothing; optimal speeds of the taken- in;
low doffer speeds, lower through put.
4. Elimination of short fibers: Short fibers can only be
eliminated if they are pressed into the clothing.
Elimination of short fibers in the card must be
viewed in proportion, actually very small, fewer
than, 1% short fibers.
5. Fiber blending: The card is the only m/c to process
individual fibers. In formation of the web and with
repeated rotation of the fibers on the main cylinder,
intimate fiber with fiber mixing is achieved.
6. Fiber orientation: It is often attribute the effect of
parallelizing. The card can be given the task of
creating partial longitudinal orientation of the
fibers.

72
7. Sliver formation: To deposit the fiber material, to
transport it and process it further , an appropriate
product must be formed.
So carding is called Heart of spinning”

Different action in card m/c:

I) Carding Action: If two closed surfaces have opposite
wire direction and their speed direction or relative
motion is also opposite, then the action bet n two surfaces
is known as carding action:

 It is occurred betn flat and cylinder.

 Here wire direction is opposite
 Speed direction is opposite
 If the two surfaces move in the same direction but
at different speed.
 There always should be point against point
direction.
Result by the action of carding –
 Maximum individualization of fibers isachieved in
this region by opposite spikes.
 Neps, short fibers, dirt & dust are removed .

73
  The difference of surface speed bet n cylinder & flat
is more.
So carding action is maximum occurred

II) Stripping Action: When two close surfaces have same

wire direction and their speed direction or relative
motion is also same then the action bet n two surfaces is
called stripping action.
Stripping action is occurred bet n
 Taker in and Cylinder
 Doffer and Stripper.


o Same wire direction & speed direction.
o There always should be point against back action.
Result by the action of stripping:
 Trash, reps are transferred from cylinder, taker in
and taker in by stripping action.
III) Doffing action: When two close surfaces wire
points are inclined in opposite direction and their
speed direction is same, then the action betn two
surfaces is called doffing.

74
  Stripping action is occurred bet n
cylinder and doffer
 Wire direction is opposite but speed
direction is same.
 It is special type of carding
 Sliver formation – is done by this
action.
IV) Combing action:
 This action take place betn feed roller & taker in
 Here pin direction is same.

Distinguish betn Carding action and stripping action:

Carding Action Stripping action
1. Two surfaces wire point 1. Two surfaces wire point
are inclined in opposite are inclined at the same
direction. direction.
2. Their speed direction is 2. Their speed direction is
opposite same.
3. It is occurred betn flat & 3. It is occurred betn (i)
cylinder Taker in and cylinder &
(ii) Doffer and striper.
4. As in this action, two 4. As in this action, two
surfaces are in opposite surfaces are in the same
direction, so minimum direction, so maximum
amount of fiber stay in amount of fiber stay in
lower speedy surface. lower speedy surface.
5. Fibers are mainly 5. Fibers are mainly
individualized by this individualized by this
action. action.
6. Point against point 6. Point against point
75
 action. action.
Distinguish betn Cording Action & Doffing action:
Carding Doffing
1. Two surfaces wire point 1. Two surfaces wire point
are inclined in opposite are inclined in opposite
direction & their speed direction but their
direction is also opposite. speed direction is same.
2. It is occurred betn flat & 2. It is occurred betn
cylinder cylinder & doffer.
3. The speed difference betn 3. The speed difference
two surfaces are more. betn two surfaces are
4. Minm amount of fibre less.
stay in lower speedy 4. Some amount of fibre
surface. stay in lower speedy
5. Fibres are mainly surface.
individualized by this 5. Sliver formation is
action. performed by this
action.

Operating principle of Modern high performance card:

 Raw materials is supplied from the pipe ducting(1) to
the card chute(2). The transport roller(3) forward the
material to feed arrangement(4).
 The feed rollers pushes the sheet of fibres to the taker
in(5). These flocks are passed over the grid
equipment(6) and transfer to the main cylinder(8).

76
 During passing the materials between (5) and (6)
greater parts of impurities looses and suction duct(7)
carries the waste.
 The flock carries along the cylinder, penetrate to the
flats(10) up to open individual fibres the actual carding
action cause during passes between these two device.
 The flats are consist of about 80-166 carding bar. Some
of 30-45 flats carries with the cylinder and the rest of
are return run.

 During this return, a cleaning unit(11) separate the

short fibres, neps and foreign materials from the flats.
 Two fixed carding bar(9) and (12) are designed to
assist the carding operation. After carding, the cylinder
carries loose fibres which lie parallel without hook and
77
 they are not transportable. So a doffer(14) is used to
combines the fibres into web.
 A stripping device(15) draw the web from the doffer.
After calendar roller(16) compressed the sliver to some
extent. The coiler(18) deposits it in cans(17).
 The working roller, cylinder and flats are provided
with clothing which becomes worn during fibre
processing and must be grounded at regular intervals.

Feature:
1. Production: Four times higher than
conventional card m/c
2. Speed : Cylinder = 310 r pm, doffer = 7 to 35
rpm, taker in = 910 r pm.
3. Taker in region: Need extra cleaning and
opening arrangement.
4. Here combing bar used instead of Mote knife
5. Feed end: Adjustable lap stand to
accommodate up to 2.4˝ dia lap
6. Cylinder under casing: strong and distance
betn two kept is least.
7. Stop motion: In high production carding
m/c use and types of stop motion: such as -
feed end and cam stop.
8. Flats: flat speed remains same but
mechanically improvement is done.
9. Doffing: In high production carding m/c,
use doffing roller instead of doffing comb.
78
 10. Suction Unit: Three or four suction units are
used.
Advantage:
 High production
 Lower labour cost.
 Less doffing frequency
 Less wastage
 Less stripping
 Less grinding.

Card Clothing:
The inclined wires set in base material, which are covered
around the surface of Taker-in, cylinder, doffer and flat in
the carding machine is called.Of all the individual
components of the card, the clothing has the greatest
influence on quality and productivity.

Types of card clothing:

Card clothing is divided into three groups –
I) Flexible clothing.
II) Semi – rigid clothing
III) Metallic clothing

I) Flexible Clothing: These have hooks of round or oval

wire set into elastic, multiple-ply cloth backings. Each
hook is

79
bent to a U-shape and is formed with a knee that flexes
under bending load and returns to its original position
when the load is removed .Flexible clothing is used in
cylinder, flats and doffer.
Advantage:
 Point density is high, so cording action is good.
 Wire point flexible, so fiber damage is less.
 FiNer yarn count can be prepared
 If there is damage in any parts, needs repair in
those of parts.
 Low cost.
Disadvantage:
 Foundation material i.e. Textile fabric, rubber
required.
 Wires may be loose.
 Low production for stripping action.
 Grinding should be regular.
 Wire and foundation material may get damage
because of they are both flexible.
 Fiber becomes lose for grinding action.
80
  Any carding angle cannot be chosen.

III) Metallic Clothing : These are continuous, self

supporting wire structures in which teeth are cut at the
smallest possible spacing. They do not need any base
material. The wire has no knee. Metal surface of m/c acts
as a metallic foundation. Now a days, they are used in
Taker-in, cylinder and doffer.

Advantage:
 Metallic clothing needed no separate foundation
material but metal surface of m/c acts as a
foundation material.
 As teeth and foundation are both metallic, there is
no possibility of “teeth loose”
 Any carding angle can be chosen.
 No change of tooth angle due to carding action and
fiber do not embed to teeth. No need of stripping.
As a result, save much time.
 No need of regular grinding.

81
  Saved 3% good fiber and increase production 18-
20% due to no need of stripping and grinding.

Disadvantage:
 Carding action is not better due to less point
density.
 More fiber damage due to metallic of teeth.
 Difficult to repair, complete reclothing necessary.
 Initial cost high
 Not suitable to prepare firer count.
 Liberates more fly and pollutes air.
 Requires higher starting torque.

Differentiate betn Flexible & Metallic card clothing:

Flexible card clothing Metallic card clothing
1. Teeth have knees. 1. Teeth have no knees.
2. There is possibility of 2. There is no possibility of
damage of foundation; damage of foundation;
the teeth become loose. the teeth become loose
on foundation.
3. Any carding angle 3. Any carding angle can
cannot be chosen. be chosen.
4. Regular grinding is 4. Regular grinding is not
necessary. necessary.
5. Stripping is necessary. 5. Stripping is not
necessary.
6. Carding action is good
due to high point 6. Carding action is not
density. better due to less pint
density.
82
7. Only damaged portion
can be replaced. 7. Difficult to repair;
complete reclothing
8. Low cost. necessary.

8. High cost.

Advantage and disadvantage of Metallic clothing over

flexible clothing:

I) Advantage of Metallic clothing over flexible clothing:

 Metallic clothing needed no separate foundation
mtl and metal surface acts as a foundation mtl.but
Flexible clothing needed textile fabric ,rubber as
foundation material.
 There is no possibility of “teeth loose” in case of
metallic clothing but there is possibility of “flexible
wire looses” of flexible clothing.
 Metallic clothing needed less grinding and
stripping, but flexible clothing needed regular
grinding and stripping.
 Metallic clothing ensures chosen of any carding
angle, but flexible clothing cannot do this job.
 Teeth cannot be loose in case of metallic clothing
and teeth can be loose of Flexible Clothing.

II) Disadvantage:
 Incase of metallic clothing, carding action is not
better due to less point density. But carding action
is better due to high point density.
83
  Metallic clothing is costly. But flexible clothing is
cheap .
 More fiber damage in case of metallic clothing, less
fibre damage in case of flexible clothing.
 Difficult to repair, complete reclothing necessary in
case of M.C. Incase of flexible clothing, no difficult
to repair; only damaged portion can be repaired.
 Finer yarn count cannot be prepared in case of M.C
and finer yarn can be in F.C.

III) Semi–rigid clothing: These are less elastic than those

of flexible clothings. These backing are multiple-ply
structures, with more plies, than the backing of flexible
clothing, comprising both cloth and plastics layers. The
wires are not formed with a knee. The wires cannot band
and they do not need sharpening. When subjected to
bending load, they are therefore much less capable of
yielding than flexible clothing.
Semi – rigid clothing is used in flat for wood and long
staple fibre.

Advantage:
1. No need of frequent sharpening.

84
2. No need of stripping as well as there is no knee and no
dirt and dust is stored.

Selection of Card clothing:

 Type and design of card.
 Rotational speed of cylinder.
 Production rate.
 Material through put.
 Raw material type (natural or synthetic fibers)
 Fiber characteristics (mainly fineness , length, bulk
etc.)
 Overall quality requirements.
 Price of the clothing.
 Service offered by the clothing supplier.

Effectiveness of clothing influenced by following factors

:
 The quality of wire.
 The gauge of wire (no. of wire per sq)
 The insertion angle of wire in the foundation.
 The angle formed at the knee.
 The relative heights of knees and points.
 The grinding of the point
 The density of the wires.
 The manner of insertion of the wires in the
foundation.
The most important operating parameters of the clothing:
Several important factors & dimensions:

85
 1. Point density.
2. Base width (a1 )
3. Height of the clothing (h 1 )
4. Tooth pitch. (t)
5. Carding angle
6. The tooth point
7. The base of the tooth
8. Tooth hardness.

Carding angle:
This is the most important angle of the teeth,
aggressiveness of the clothing, the hold on the fibers is
determined by carding angle.
The angle specifies the inclination of the leading face of the
tooth to a vertical.
It is described as positive, negative or neutral.
The angle is neutral if the leading edge of the tooth lies in
the vertical (00 ).
Carding angle normally fall into the following ranges:
Taker in → +50 to -100 (-150 )
Cylinder → +120 to 270
Doffer → +200 to +400

Fig: (-) Carding angle (+) Carding angle

86
Card Clothing Unit/Point density and calculation for point
density:
Point density means; point per unit surface area. Point density
have significant effect on the carding action. However, the
number of the points and speed of the rotation of cylinder
must be considered.
i.e. Number of point  Surface speed ( dN) = Constant
The higher point density, the better carding effect up to a
certain optimum limit. After this limit, negative effect are
shown. This limit/ range is depends on the materials. Coarser
count need fewer point and it take up more space into the
card. Finer fibre processed in more point, because, if the fibre
throughput is same then more fibre present into the card.
Calculation: Point density is referred by number of point per
square inch or square centimeter. The calculations are,
645
Point/Inch 2 
Base width(mm)  Pitch(mm)
100
Point/cm 2 
Base width(mm)  Pitch(mm)

Pitch = Tip to tip of teeth distance.

So, the narrow the base, the more cylinder rotation (i.e. r is
decreases) that is, the higher point density.

Grinding:
Grinding is the operation by which the effectiveness of the
wire points of all organs in the carding m/c is maintained.
Wire pints of different organs i.e. Taker-in, doffer, cylinder
and flats, loss their effectiveness in regular fiber processing
and variable weight of wire points and get irregular
87
carding action. So grinding is necessary to make the
points, sharp after grinding, the height of wire is reduced.

If grinding is not done, due to the action of cotton and dirt

with the wires the points of wires (teeth) become round at
the top (i.e. blunt) and loose their aggressiveness.
Objects of grinding:
 To increase Sharpness of the wire points.
 To keep equal height of wires.
 To get regular carding action and uniform sliver.

Types of Grinding:
1. Traverse wheel grinding or horse fall
grinder.
2. Dead, long grinder.
1. Traverse wheel grinding: Traversing wheel grinding
device contains an emery wheel of 3.5˝ width which
performs grinding process by traversing motion, moving
from one end to another across the wire pints of different
parts.

Advantage: I) Better grinding action.

II) No risk of hooking or fusing of wires.

88
2. Long roller grinding: This device provides a long roller,
which moves over full width of cylinder surface and
performs grinding process.

Advantage:
I) It is suitable for high speed grinding.
II)It is used for low and medium count yam.

Card setting of Revolving flat card :

The main components of carding m/cs are taker in to
cylinder, cylinder to flat, cylinder to Doffer etc. have set
the distance.
1. Feed plate to taker in: 0.009˝ - 0.012˝
2. Lap guide to edges of feed roller: 0.075˝ - 0.001˝
3. Mote knives to taker in:
Upper knife: 0.010˝
Lower knife: 0.012 to 0.015˝
4. Taker -in to taker- in under caging:
Forward edge: .030˝
Rare edge: 5
16"
5. Taker -in to cylinder: 0.007˝
6. Flat to cylinder: heal end: 0.010˝
Toe end: 0.030˝
7. Flat to flat stripper: 0.032˝

89
 8. Top feather edge sheet to cylinder:
Upper edge: 0.010 to 0.060˝
Lower edge: 0.032˝
9. Bottom sheet to cylinder:
Upper edge: 0.0324˝
Lower edge: 0.015˝
10. Cylinder to Doffer: 0.005˝
11. Doffer comb to Doffer: 0.012 to 0.015˝
12. Cylinder under caging to taker in: 0.032˝
13. Cylinder under caging to cylinder:
Back: 0.012˝
Middle: 0.032˝
Front: 0.064˝
14. Back sheet to cylinder:
Upper edge 0.010˝
Lower edge 0.012˝
Importance of setting betn cylinder & flat:
 The material gets carding action.
 Maximum individualization of fibre
 Removed of neps, short fibers, dust etc.
 Parallelization of fibers.
 Straightening of fibers.

Factors considered for optimum card settings: The

optimum card setting are influenced by the following
factors:
 Type of material or staple length of material.
 Amount of trash to be removed.
90
  Weight of lap per unit length or lap hank.
 Waste percentage desired.
 General mechanical condition of the m/c and card
clothing.
 Production rate.
 Types of card clothing.
 Fiber fineness.

Function of front percentage plate: The amount of strips

removed by the flats can be regulated by the adjustable top
section of the front plate, the so-called percentage plate,
can regulate the amount of strips removed by the flats. The
closer the settings between cylinder wire and percentage
plate, less strips are removed. With the closer setting of the
plate, the wire of the cylinder has a better grip in the fiber
compared with wider setting addition, air velocity at a
closer setting might help to keep more fibers on the
cylinder surface.

Function of Heal & Toe Management: The slide surfaces

on the bars are not ground level but are slightly inclined.
This arrangement is called heal and toe arrangement.
When viewed form the direction of the material flow the
leading edge of each bar is spaced further form the
cylinder clothing than the trailing edge. The result of the
arrangement is that the fibers are not pushed along in front
of the flats, but can pass underneath it i.e. gentle action
taker place.
91
Maintenance:
1. Stripping the clothing
2. Burnishing the clothing
3. Grinding of the clothing
4. Mounting of fillet
5. Oiling and greasing
6. Attending to repair
7. Splicing of ropes.
8. Setting
9. Miscellaneous

1. Stripping the clothing:

If at all possible, metallic clothing should not be
cleaned out with a revolving brush, but rather with
a hand scraper while the cylinder is rotated
manually (not by the motor drive). Rapidly rotating
brushes create considerable metal-to-metal friction
(brush on semi-tooth-wire) and cause more wear on
the clothing points than do the fibers.

2. Burnishing the clothing:

A single brownish wears down the teeth more
strongly then processing tens of thousands of
kilograms of materials. Occasionally, this proves
necessary on the doffer. Then though, burnishing
must be carried out in the direction of the teeth and
not against them.
92
 3. Grinding of the clothing:
a. Intervals between grinding:
Cylinder Flats
1st grind after 80-150000kg 120-
150,000kg
Each additional grind after 80-120,000kg80-
120,000kg
b. Depth of grind: The depth of grind is such that a
plane surface with a sharp edge is produced at the
point of the tooth.
c. Grinding of the flats: There are two possibilities,
namely grinding in the card under normal
production conditions or grinding of the flats in a
special grinding m/c after removing them from the
card.
4. Mounting of fillet:
If broken wire is found in m/c, should be repair
instantly. Generally fillet of cylinder ,doffer is
changed after each 26 days and in Taker- in one
time in a month.
5. Oiling and greasing: Should be oiling and greasing
daily.
6. Attending to repair:
Should repair the m/c instantly otherwise increase
loss of production and risk of dangerous.
7. Splicing of ropes: Should change rope after splicing.
8. Setting: Should observe card setting each ten days.
93
 9. Miscellaneous: Each roller should be kept in stand
not keep in floor.

Auxiliary Equipment:
I) Dust extractors on high performance card:
The card releases enormous quantities of dust and it is
essential to ensure comprehensive and immediate removal
of this waste. For this, modern cards are fully enclosed and
subjected to permanent under pressure, so that dust and
fly can no longer escape form the m/c. Within the casing,
suction removal system are provided at some or all of the
following positions:
 In the feed region
 At the entrance to the flats
 Within the flats
 At the exit from the flats
 Between the main cylinder and the doffer
 At the web detaching point
 Beneath the main cylinder.
 In the coiler.

The suction removal systems operate continuously to

maintain constant conditions at the card. The quantity of
suction air per card lies in the range from about 2000 to
2500 m3 /hr.

II) Waste disposal:

94
The card eliminates approx 4% waste in a carding room
processing 500kg/hr; about 500kg waste is produced per
day in the three-shift operation. This waste falls into two
categories:
 Dropping form below the cared.
 Flats and fitter stripping.
Filter waste can be removed manually but now -a-days,
attendants can not be asked to perform manual removal of
taker in droppings. Modern cards are there fore fitted with
suction-waste-removal systems. These can operate either
continuously or intermittently.

Card waste:
I) Motes and fly 33%
II) Flat strip 45%
III) Cylinder strip 16%
IV) Doffer Strip 2.5%
V) Clearer waste 
VI) Sweeping waste 

 3.5%
VII) Reusable waste 

Carding faults:
1.Sliver variation: causes
 Irregular and uneven feed.
 Damaged feed roller/doffer/calendar roller
 Wide setting of feed plate to feed roller and Taker
in to cylinder.

95
  To much tension betn doffer and calendar roller and
calendar roller to coiler head.
Remedies:
 Regular and even feeding
 Grinding doffer, making effective feed roller and
calendar roller.
 Controlling tension is delivery region.

2. Cloudy web: Causes: -

 Over loading of wires
 Damaged wires on cylinder, doffer, flats taker -in
 Wider setting bet n cylinder and flats.
 Feed plate is setted too far from taker- in
Remedies:
 Grinding the organs of card
 By correction the error setting.
 Improvement feed roller grip.

3. Hole in web: Causes:

 Damaged wire on organs of card especially on
doffer.
 Various heights of wire points.
Remedies:
Location the damaged wire portions on doffer &
replacing the damaged portion skill fully and then
leveling the new wires with the rest of doffer wire
points.
96
4. High nep count : causes :
 In correct setting (e.g. doffer to cylinder, cylinder to
flat)
 Dull or damaged cylinder, doffer or taken -in wires.
 Wider setting bet n cylinder and flat or doffer and
cylinder
 Too high R.H%
Remedies:
 Correction the incorrect setting
 Grinding wire points.
 Maintaining R.H%
For cotton R.H → 45-55%, Temp 70-
80 F
0

For synthetic, RH → 55-56% Temp 80-

900 F

5. Web sagging: Causes:

 Lower tension draft betn doffer and cylinder
 High doffer speed.
 Low humidity.

Remedies:
 Increasing tension draft betn doffer and cylinder
 Reducing doffer speed
 Maintaining humidity as 50-60%

Function of flats:
 Opening of flocks to individual fibers
97
  Elimination of remaining impurities.
 Elimination of some of the short fibers
 Untangling neps (possibly their elimination)
 Dust removal
 High degree of longitudinal orientation of the
fibres.

Recent development of cotton card:

Using the following process holds the recent development
of cotton card:
 Metal detector
 Auto leveling
 Continuous suction
 Chute feed system
 Electronic control system
 Each section is driven by separate motion.

How can reduce reps in card sliver:

1. Closer spacing betn the clothing.
2. Sharper clothing.
3. Optional speed of the taker in
4. Low doffer speed
5. Lower through put.

Influence of taker in speed on yarn quality:

The greatest part of opening and clearing of fiber takes
place and performed by taker- in. About 50% of fiber tuft is
made individual fibers by taker- in.

98
The degree of fiber deterioration can be controlled by
adjustment of:
 The thickness of the belt.
 The degree of openness of raw material in feed
stock.
 The degree of orientation of fiber in feet stock
 The aggressiveness of the clothing
 The distance bet n the devices
 The rotational velocity of the taker in the material
through put.
A
I II III IV V VI
%
100

50

740 1040 740 1040 740 1040 740 1040 740 1040 740 1040 B

Fig: Influence of the rotation rate of the taker-in on the yarn

(A)parmameters comparison value in %
(B) Taker in rotatation rate(rpm)
I- Neps, II- Thick places, III- Thin places, IV- Yarn evenness,
V- Yarn strength , VI- Imperfections

By the above graph, it is obvious that is taker in speed is

less (i.e. 740rpm) the yarn quality will be better than that
of higher taker in speed (i.e. 1040 rpm). Lower speed will
99
cause less reps, thick place thin places, more yarn strength
than that of higher speed.

Additional carding segments:

Carding aids can be applied at three positions:
 Under the taker- in
 Between the taker in and the flats
 Between the flats and the doffer

This aids are in the form of carding plates or carding bars

in the religion of taker in (a) plates are usually used, while
bars are being located increasingly in the region of the
main cylinder (b) in

case of carding segments, under taker- in grid bass are

replaced by carding segments. There the fiber and flock is
guided over the following devices one after another.
(a) Mote knife-1 → (b) Carding segment-1
100
 (c) Mote knife-2 → (d) Carding segment-2

Effect of carding segment on to carding action:

If carding segments are not used, the taker -in delivers more
flock. These flocks are compressed and poorly distribute
across the taker -in and when they pass between the flats and
cylinder, it creates extra pressure on the clothing and also the
carding action suffers.
But if segment are included-

We can ensure the

 Further opening
 Thinning out.
 Spreading out.
 And over all distribute on to the surface of the card.

Carding segment reduce the loading of flat/cylinder. The

diagram illustrated the loading with and without carding
segment used. It is clear that, most open occurs, in the first flat.

The carding segment brings the following advantages:

sImprove the dirt and dust elimination.
1. Improve the speed of the flat and hence production
increases.
2. The quality of yarn increases.
3. Improve the entangling neps.
4. Preservation of clothing, hence longer life of clothing.
5. Finer clothing can be used.

101
 6. Cleaner cloth.
7. Greater fibre orientation and more transfers the fibre to
the doffer.

Advantage and Dis-advantages of Flat drive for its backward

and forward movement.
Movement of the flat: The bar of the flat is individual as like
toothed wheel and set it into the sprocket. The end of the bar
of drive flat slide over the continuous bend with metal to
metal friction. To reduce this friction and ensure a steady
forward movement, crosrol are provided on the both ends of
the bar by ball-bearing to slide over the bend.
In this principle, the flat can be forward or backward
movement i.e. same or opposite movement to the cylinder.
For movement with(forward) cylinder-
i) The cylinder assist the drive to the flat.
ii) So removal stripping is easier.
But- i) It transport the immediate dirt through the hole
machine.
There have some technical advantage in case Backward
movement.
1) The bar of flat is cleaned when it come into
relationship with the cylinder clothing of doffer side.
After that it moves towards the taker in and then filled
up the bar above the taker. Here disadvantages, the flat
capacity is lost to till up. But advantages are, the
remain dirt is eliminated by this action when the fibre
first enters into the flat above the taker in.
102
 2) To clean the fibre, the cylinder carry it into the flat and
take up the dirt but the dirt are not transport through
the hole m/c. The Rieter flat is shown tat, the cleanness
of the dirt occurring into the first flat above the taker
in.
A – Flat loading.
B – Number of flat bar in the mtl flow direction.
Advantages of carding segments: /Effect

1. Improved dirt and dust elimination.

2. Improved untangling of neps and speed

increase and here a production increases.
3. Preservation of clothing and hence longer
life of clothing.
4. The possibility of using firer clothings.
5. Better yarn quality.
6. Less damage to the clothing.
7. Clearer clothings.

Typical Specification of card:

Part Angle wire Speed Dia
Taker in → +50 to -100 (-150 ) 600-1000 rpm 250mm
Cylinder → +120 to +270 250-600 1300 mm
Doffer → +200 to +400 5-15 rpm 600-750mm
Lap Roller → --- 1 ft/min 50 mm
Feed Roller → --- 1ft/min 55mm

103
What happens when:
I) DCP is changed
II) PCW is changed or Barrow wheel is changed.
III) Feed roller and doffer speed is changed.
IV) Take - in change of speed (Effect of taker-in)
I) DCP: Means Draft Change Pinion. During carding if
need to change draft then pinion generally changes.
The no of the teeth of this changed DCP higher then
draft will less. If number of teeth is less then draft will
high.
1
i.e DCP 
draft
II) PCW: PCW means production change wheel. By the
help of PCW, production can be more or less. If we
want to increase the production ,the number of teeth of
the wheel should be increase and if we want to
decrease the production ,the no of teeth of the wheel
should be decrease.
i.e. production  pcw
III) Feed roller and doffer speed is changed:
Feed roller and doffer speed decreases, keeping the other
parts of the m/c const then it help to improve web
quality. Because taker in, cylinder and flats act upon
less material so opening and cleaning action will be
very good and finally carding action will be high.

If feed roller and doffer speed increased, keeping the other

parts of the m/c constant, then it does not improve web
104
 quality. Because taker in, cylinder and flats act upon
more quantity material, so opening and cleaning action
will be bad and finally carding action will be bad .

Auto leveling:
For regular delivery or regular out put of material
changing draft according to the change of input amount is
called auto leveling.
The main regulating position is feed, auto leveling is
usually performed by adjusting the feed roller speed.
Virtually autoleveling devices exploit this possibility,
adjustment of delivery speed is hardly ever used.
A distinction should also be drawn between:
I) Short-term auto leveling systems, regulating
lengths of product from 10-12 cm.
II) Medium-term auto leveling systems, for
lengths above 3m
II) Long-term auto levelers above 20m

Control Systems of Auto leveling:

I) Open loop control
II) Close loop control

I) Open loop control:

A measuring sensor is provided in the region of the
infeed for

105
 t

F E

A = Measuring sensor
B = Store
C = Amplifier
D
D = Adjusting Device
E = Adjusting Point
F = Set Value Input
B C

Fig: Principle of open loop control

continuous detection of the actual value – mechanically,
optically, pneumatically or otherwise. A regulator
compares the result with the set reference value,
amplifies the difference signal and feeds it to an adjusting
device. Control by this chain of steps requires an
additional element, namely the store. Since the material
has to travel certain distance bet n a measuring and
adjusting points and arrives at the adjusting points with a
time delay, the signal must be held back in the store.
Disadvantage:
 Lack of self monitoring
 Vary exact values of the adjustment are required all
times.
 If measuring sensor improper, not possible to
control regularity.
Advantage:
 Accurate regularity maintaining is possible
106
  Suitable for compensate the variation of short to
medium wave length.

II) Closed loop control:

The measuring sensor is arranged in the delivery region
that is
F

A = Measuring sensor
C = Amplifier
D = Adjusting Device
D
F = Set Value Input

Fig: Principle of open loop control

down stream from the adjusting device. The measuring
point is after the adjusting point. The same measuring,
regulating and adjusting devices can be used, but no store
is reduced. If too much material passes through the sensor
the regulating transmission receives a negative signal (i.e.
reduce speed) until the actual and set values coincide. The
measured portion has long passed the adjusting point
when the adjusting signal arrives.

Advantage:
 Suitable for compenastation errors of
longwavelength.
 A past of faults can be eliminated by it in 1 st
passage

107
Disadvantage:
 Can not eliminates picings as finely as open loop
control
 Very costly

Pneumatic measuring device:

In normal card, a funnel is provided before the calender
roller (2) in order to collect the web in to a sliver.
This funnel is developed to form a measuring device.
When fiber material enters into the funnel (3) carries along
quite an amount of air held bet n the fibers. This generates a
super atmospheric air-pressure.

Fig: Pneumatic measuring system

A lateral bore (5) in the funnel and corresponding leads,
transmit the pressure into the chamber of a pneumatic
electrical pressure transducer. Comparison of the signal
with a set value enables the generation of pulses to control
the electronic units in the regulating equipment.

108
Advantage: Simplicity of the system which dues not
require additional or sensitive moving parts.

Disadvantage: The fibre fineness affect measurement and

hence fineness variation can lead to errors.
Characteristics of carded sliver:
1. Carded sliver are oriented in different
direction
2. Not proper uniform
3. More wt/unit length
4. The mores fibers are projected out of the
slivers.
5. Hook is present.
6. More short fibres %
7. Sliver Hank: 0.12-0.20
8. Draft → 85-100
9. Wt/yds / sliver 70-82 grains
10. Production per hr: 6-16 lbs

Difference between carded & combed yarn:

Carded yarn Combed yarn
1. The yarn that is 1. The yarn that is
obtained without obtained by combing
combing is called is called combed yarn.
carded yarn.
2. Quality of carded yarn 2. Quality of combed
not better than yarn better than
109
 Carded yarn Combed yarn
combed yarn. carded yarn.
3. Short fibre% is high. 3. Short fibre% is low.
4. Combing action is not 4. Combing action is
done here. done here.
5. Less strength. 5. Higher strength.
6. Irregular. 6. Regular.

Mathematical problem

Problem-01: Find out the sliver Hank of a Carding m/c from

the following data:
Lap weight=14 ozs/yds
Draft=100, Waste=4%
L=1Yds
Solution:
w=1lb
Lxw l =840Yds
Lap count=
l xW W=14 ozs/yds
1x1 14

840 x0.875 = 16 lb/yds
=1.36x10-3 Ne =0.875 lb/yds

100  waste%
Mechanical draft=Actual draft x
100
 100x100=Actual draft(100-4)
10000
 Actual draft   104.167
100  4
Again Delivery Hank=Actual draft x Feed hank

110
 =104.167 X1.36x10-3
=0.1416 Ne
Problem-02: Find out the production per day in lbs of a
Modern Carding m/c from the following data-
Doffer speed=200m/min
Delivery sliver weight-68grains/Yds
Waste=3%, Efficiency=95%
Tension draft=1.1
Solution:
200x1.09x60x24x68x0.95x1.1x(100-3)
Production per day= 100x7000
 3091.13 lbs
Problem-03: A Carding m/c running with following-
RPM of feed roller=1.5
RPM of feed doffer=10
Dia of feed roller=2.25"
Dia of doffer=27"
Hank=0.14
Find Mechanical draft and production.
Mechanical draft
Surface speed pf doffer

Surface speed pf feed roller
 x10 x 27
  80
 x1.5 x 2.25
10 x x 27 x60 x 0.95
Production=   11.41lb / hr
36 x 0.14 x840

Problem-04: Find the production per shift of Carding machine

Doffer speed=400rpm
Doffer dia=27"
111
Hank of sliver=0.14
Efficiency= 85%
Tension draft=13
Solution:
 x27x400x60x0.85
Production of the Card 
36x0.14x840
 408.52lb / hrs
Problem-05: Find the draft of Carding m/c if lap weight
500gm/m and sliver hank=0.122
Solution:
Delivery hank
Draft=
Feed hank W  500 gm / m
Lxw
 Feed hank or Lap count= 500x0.9114
lxW =
453.6
1x1
= =1.0046 gm
840x1.0046
=1.18x10-3 Ne
0.122
 Draft=
1.18x10-3
=1.02.95
Problem-06: Lap hank =0.0012 Ne, Sliver hank is 11. Find draft
fo Carding m/c.
Solution:
Delivery hank
Draft=
Feed hank
11
=  9166.67
0.0012

112
Problem-07: Find actual draft of a Carding m/c for mechanical
draft=86, Waste extraction=7%, Lap hank is 0.0012, what will
be sliver hank?
Solution:
Mechanical draft
Actual draft= x 100
100-waste%
86
= x100  92.47
100-7
Delivery hank
Actual Draft=
Feed hank
 Delivery hank=92.47 x0.0012=0.1109

Problem-8: Find out Production /day in lb in Modern

Carding m/c-
Doffer speed=200m/min
Doffer dia=27"
Delivery slivefr weight=68 grains/yds
Efficiency=95%, Tension draft=1.1
Waste=3%
Solution: W=68 grains/ yds
Lxw 68
Sliver count 
Wxl = 7000 lb/yds
1 x1 [7000 grain=1 lb]
=
68
x840
7000
=0.122 Ne

113
 200x1.09x60x24x x27x0.95x1.11x(100-3)
 Production per day=
36x0.122x840
=7283.313756 lb/day

Problem-09: A Carding Spinning mill has 10 cards. It runs .

Find out the production per dau in kg from the following
data-
Delivery speed=200m/min
Doffer dia=27"
Delivery sliver weight=70 grains/ yds
Card efficiency=95%,Dia of the feed roller=2.25"
Solution:
1 x1
Sliver hank=  0.11
70
x840
7000
200x1.09x60x24x x27x0.95x10
Production per day=
36x0.11x840
=70267.37 lb/day
=31881.74 kg/day

Chapter

4 Draw
Draw frame
Frame
Drawing: It is a process of yarn manufacturing in which the
sliver is enlongated when passing through pairs of rollers,
each pair faster than the previous one.

114
This permits combination of several slivers and drawing and
enlongating them to straighten and to create greater
uniformity.

Objects of drawing:
I) To straighten the fibres in the slivers.
II) To make them lie is a manner parallel to their
neighbours and to the sliver axis.
III) To improve the uniformity and evenness of the
slivers.
IV) To reduce weight per unit length of sliver.
V) To reduce irregularities of fibre by doubling and
drafting.
VI) To remove dust from sliver.
VII) To make perfect blending of the sliver.

Necessity of draw frame:

To parallisation of fibre and blending carded→ Carded sliver.
In carded sliver, fibre present in hook form i.e. trailing hooks
and leading hooks.
To parallel those hook, draw frame is used.

Majority of the fibre hooks in a carded sliver are trailing while

leading hooks are comparatively less. Trailing hooks are also

115
known Mazor hooks. While leading hooks are known as
Minor hooks.

Tasks of draw frame:

I) Equalizing.
II) Parallelizing.
III) Blending.
IV) Dust removal.

I) Equalizing: One of the main tasks of the draw frame is

improving evenness over short, medium and especially
long terms. Carded slivers fed to the draw frame have
degree of unevenness that can not be tolerated in practice
and slivers from the comber contain the ‘infamous’
piecing. It is obscured by draw frame.
Equalizing is always performed by a first process, namely
doubling and can optionally also be performed by a
second process, namely autolevelling. The draft and the
doublings often have the same value and lie in the range of
6 to 8

II) Parallelizing: To obtain an optimal value for strength in

the yarn characteristics, the fibres must be arranged
parallel in the fibre strand. The draw frame has the task of
creating this parallel arrangement. It fulfils the task by way
of the draft, since every drafting step leads to straightening
of the fibres.

116
 III) Blending: In addition to the equalizing effect, doubling
also provides a degree of compensation of raw material
variation by blending. This result is exploited in particular
in the production of blended yarns comprising
cotton/synthetic or synthetic/synthetic blends.
IV) Dust removal: Dust is steadily becoming a great problem
both in processing and for personnel involved. It is
therefore important to remove dust to the greatest
practical extent at every possible points within the overall
process. Dust removal can only be carried out to a
significant degree when there are high levels of fibre/fibre
or fibre/metal friction since a large friction the smallest
particles(dust) adhere relatively strongly to the fibres.
The draw frame is therefore a good dust removing m/c; on
high performance draw frame equipped with appropriate
suction removal systems, more than 80% of the incoming
dust is extracted.

Actions involved in Draw frame:

I) Drafting: The process of attenuating or increasing
length per unit weight of sliver. It is mainly due to
peripheral speed of the rollers.
II) Doubling: The process of combing two or more carded
sliver into a single form is called doubling. In draw
frame m/c generally six slivers are fed and converted
into one i.e. six doubling.
III) Drawing: In the cotton Industry, the term is applied
exclusively to processing on the draw frame, where the
operation is one of doubling and drafting.
117
 Drawing = Drafting + Doubling.

Operating device:
 Creel (Sliver feed)
 The drafting arrangement.
 Suction systems for the drafting arrangement.
 Coiling.
 Can changers.
Creel: The creel must be designed so that:
 False drafts are avoided.
 The m/c stops upon occurrence of sliver break.
 Sliver breaks can be dealt with easily, comfortably and
safely.
For this purpose, it is necessary to produce a rotable roller or
roller pain above each can. A guiding device for leading the
rollers into the drafting arrangement is also required. A table
with rollers or simply a line of rollers, can provide the
required guidance.

Requirements of drafting arrangements:

The drafting arrangement is the heart of the draw frame and
thus the part which exerts the most decisive influence on
quality. The requirements placed on the drafting arrangement
in general are correspondingly high:
 Simple, Uncomplicated construction.
 Stable design with smooth running of the rollers.
 A mode of operation giving a high quality product even
at high running speeds.
118
  High degree of flexibility i.e. suitability for all raw mtls.
 Optimal control over the movement of the fibres during
the drafting operation.
 High precision both of operation and adjustment.
 Rapid and simple adjustability of roller spacing and draft
levels.
 Ease of maintenance and cleanings.
 Optimal ergonomic design.

Influence of the draft: Factors that affect the draft:

Factors dependent upon the fibre mtl:
I) Mass of the fibre in the strand cross-section.
II) Degree of order of the fibre.
III) Shape of cross section of the fibre strand.
IV) Compactness of the fibre strand.
V) Adhesion betn the fibres depend upon-
 Surface structure.
 Crimp.
 Lubrication.
 Compression of the strand.
VI) Fibre length.
VII) Evenness of distribution of fibre lengths.
VIII) Twist in the fibre strand.

Factors depending upon the drafting arrangements:

I) Diameter of the rollers.
II) Hardness of top rollers.
III) Pressure exerted by the top rollers.
119
 IV) Surface characteristics of the top rollers.
V) Fluting the bottom rollers.
VI) Type and form of fibre guiding devices, such as
pressure rods, pin bars, aprons, condenser etc.
VII) Clamping distances(Roller setting)
VIII) Level of the draft.
IX) Distribution of draft betn the various drafting
stages.

Forms of drafting arrangement used on draw frame:

1. 3 over 4 roller drafting arrangement:
 The characteristics feature of this arrangement is
engagement of the middle pressure roller with two
bottom rollers.
 The two bottom rollers are carried in a common
cradle and are not adjustable relative to each other.
 A pressure bar may also be used in the main
drafting field.
 The slivers enter into the back roller nip and are
subjected to a small draft betn 1.07 and 2 between
the back rollers and the middle 1 over 2
arrangement.
 There is no draft front pair of roller under going
the major part of draft in this zone.
 No roller slip occurs due to the middle (1 over 2)
arrangement.

120
  This type of arrangement is now found mainly in
the combing room, but also still to some extent on
draw frames such as Marzoli and Vouk m/cs.

Advantages:
 The widely change of setting range is possible.
 Control of fibre is increased due to drafting over
surface.
 Suitable for processing of long fibre.

Disadvantages:
 Not suitable for processing of short fibre.
 Not make so much close of nep setting of back and
front zone as 4 over 4 system.
 No drafting in the middle zone.

2. 3 over 3 drafting arrangement:

121
  This is probably the most widely used form of
drafting arrangement which was first developed by
Platt in 1960.
 The drafting arrangement runs more smoothly
with larger rollers.
 This applies especially to the front rollers. For a
given circumferential speed, larger rollers can be
operated at lower speeds of revolution.

 However, enlarging the rollers simultaneously

increases the nep spacing.
 In the main drafting zone, a special guide system is
needed, at least for short fibres; this is the guide rail
or pressure bar. It can operate from below or from
above.

3. 4 over 3 roller drafting arrangement:

 Strictly speaking, there is also a 3 roller, pressure
bar drafting arrangement, but a 4th roller with some

122
 what lower loading is added to the delivery roller
to act as a guide.
 This leads the web in a curve round the grooved
roller directly into the delivery trumpet, thereby
faciliting the formation of the sliver.
 The top rollers are uniform in diameter and large
in order to keep the strain imposed on them low.

4. 5 over 4 roller drafting arrangement:

 In this arrangement, five pneumatically loaded
pressure rollers rest on two large (90mm) and two
small (28mm) non adjustable bottom rollers.
 The pressure rollers are suspended from two yokes.
They have dia of 39 mm, although the three middle
rollers may be replaced by rollers of 28 mm dia
depending upon the circumference.
 Drafting is carried out in field B (break draft) and
field A (main field). The nip spacing can be read
from a scale and can be adjusted to suit the fibre
length by a simple radial shifting of rollers 2 and 4.
123
  In the main drafting field, a pressure bar ensures a
firm guidance, especially for short fibres.

 The drafting arrangement is aligned on a curve;

this permits proper guidance of the web material
flow from the vertical into the horizontal. The
curved diposition makes the system easy to service.

Elements of drafting arrangements in short staple spinning

generally:

124
1.Bottom rollers:
Bottom rollers are made of steel and are mounted in roller
stands or in the frame by means of needle, roller or ball
bearings. They are positively driven from the main gear
transmission. In order to improve their ability to carry the
fibres along, they are formed with flutes of one of the
following types-
I) Axial flutes.
II) Spiral flutes.
III) Knurled flutes.
Knurled flutting is used on roller receiving aprons to improve
transfer of drive to the aprons; other rollers have axial or
increasingly, spiral flutting.
The diameter of the bottom rollers can lie in the range 20-90
mm but normally diameters betn 25 to 50 is used. A drafting
arrangement includes three to six such rollers.

Fig: Axial fluted roller Fig: Spiral fluted roller

Fig: Knurled roller

2. Top rollers: The top rollers are not positively driven. They
can be either one piece rollers or twin rollers. Ball bearings are
used almost exclusively in the rollers mountings. Soft coats
around the fibre strand to greater extent than harder ones and
125
then guides the guides the fibres better. A soft coating is
therefore used where good guidance is necessary i.e. where
few fibres have to be moved with high draft levels. Hardness
is specified in terms of degrees shore. The following ranges
distinguished:
Soft coating→ 600-700 shore.
Medium coating→ 700-900 shore.
Hard coating→ above 900 shore.
Maintenance of the top roller: Since the coating wear out
during spinning, they must be reground from time to time.
This is done periodically in accordance with a predetermined
schedule using grinding discs or rollers.
Roller coatings can be treated after grinding to smooth the
surface by-
 Applying a chemical film such as lacquer or
another smoothing medium.
 Acid treatment.
 Irradiation by UV-light.

3. Top roller pressure: To clamp the fibres, the top rollers

must be forced at high pressure towards the bottom rollers.
This pressure can be generated by-
 Loading by means of dead weights.
 Spring weighting.
 Hydraulic system.
 Pneumatic weighting.
 Magnetic weighting.

126
Autoleveler: The auto leveling may be of 3 types-
I) Short term auto leveling system.
II) Medium ,, ,, ,, ,,
III) Long ,, ,, ,, ,,
Whatever be the system, the design of an auto leveler falls into
two groups-
I) Open-loop control autoleveller.
II) Closed-loop ,, ,,

I) Open-loop control autoleveller:

 In open loop autoleveller, sliver wt is measured from
input mtl.
 Here the measurement of sliver irregularity is
expressed in terms of voltage and is compared with a
desired value(DV).
 The resulting error signal is amplified(A) and after a
suitable time delay(TD) This signal is used to vary the
speed of variable speed device(S).
 A Tachogenerator(TG) ensures that the variable speed
device accurately follows the signal.

127
 Back Front
Roller Roller

Input
M
output

DV A TD S TG

M = Measuring Point, DV = Desired value, A = Amplifier, TD =

Time dealy, S = Variance speed device, TG = Tachogenerator
Fig: Open-loop control autoleveller principle.
Advantage:
 Accurate regularity maintaining is possible.
 Piecing, which arises from combing, can be partly
eliminated by open loop system.
 Suitable for compensate the variation of short to
medium wave length.

Disadvantage:
If the measuring by sensor is improper, it is not
possible to control regularity.
II) Closed-loop control autoleveller:
 In closed loop auto leveling system, sliver wt is
measured(M) from the output mtl and the resulting
signal is integrated(I).
 Then the signal is compared with the desired level.
 After amplification(A), the variable speed device(S)
varies the speed of the drafting rollers, but because of
128
 the absence of any averaging device this would cause
irregularities in output.
Back Front
Roller Roller
M
Input
output

TG S A DV

M = Measuring Point, DV = Desired value, A = Amplifier,

S = Variance speed device, TG = Tachogenerator
Fig: Closed-loop control autoleveller principle.
Advantages:
 Suitable for compensating errors of long wave length.
 It can be used in error draw frame.
 A part of faults can be eliminated by it in first passage.

Disadvantage:
 It can not eliminate piecing as finely as open loop
system.
 It is very costly.
 After going through closed loop auto-levelling system
,the sliver needs a second passage for eliminating other
faults.

Monitoring device with auto-leveling system:

I) Evener draw frame with open loop control:
129
The total volume of all slivers is measured at the in feed and
adjustment is effected with the appropriate time delay in, the
main drafting field. Detection is usually carried out
mechanically or by capacitative sensors.

II) Evener draw frames with closed loop control:

130
In this system, the evenness of the differential sliver is
measured, not the in feed sliver as in the case with open
control. The adjustment is still made in the main drafting field.
Mechanical or pneumatic sensing devices are generally used.

Monitoring: Monitoring systems can be distinguished

whether they monitor-
 The machine
 Production
 Quality
 Machine monitors are provided to ensure that the
machines are stopped immediately if a sliver breads or
runs out, if a lap forms and so on. This is most
important, since otherwise considerable damage can
be caused to the m/c.

131
  Production monitors respond primarily to
interruptions in operation of the m/c; they calculate
the efficiency of the m/c and quantity produced.
 For monitors of quality, it is againg common practice
to distinguish three different types: namely with:
 Displays.
 Self compensations.
 Auto-levelling.

Necessity of Auto stop motion: Stop motion is a device which

provided to ensure in the m/c are stopped immediately if-
 The sliver run out from the creeled can.
 Sliver breaks in the creel.
 Lap up on the drafting roller.
 Chocked in the sliver collecting plate and funnel.
 Chocke in the trumplet above the calendar roller.
 Lap on the calendar roller.
 Choke in the coiler tube.
 Opening of the head end door.
If stop motion is absent then the following defects may arise:
 Considerable damage may cause to the m/c.
 The output sliver may be thick or thin.
 Lapping up of drafting or calendar roller.
 Irregular drafting.
 Excess of full can.
 Too much waste produce.
 The strength of yarn or roving vary at different places.

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Features of modern Draw Frame: (Recent developments)
 High speed of production.
 High draft.
 Better control of short fibre.
 Autolevelling.
 Auto stop motion system.
 Electronic control and display unit.
 Auto drafting system.
 Improved drafting system.
 Can linking system.
 Rectangular can.
Fault locating indication lamp
  
Red  Stop without problem
 Green  Sliver breaks, Roller lapping
Yellow  After fill up of sliver can, no empty can
 Machine monitor

 Monitoring system  Production monitor.
 Quality monitor.

 Automatic can changer.
 Suction system for the drafting arrangement.
Effect of Draft, Doubling on sliver quality:
We know that, due to drawing and drafting the irregularity of
sliver increases but due to doubling irregularity decreases.
Let us consider that,

133
CVm = Co-efficient of variation of mass and
d = Draft
Now, CVm  d
 CVm  Kd ;
Where, k is constant for particular fibre. So from the above
eqn, we can see that, if draft increase the CV percentage also
increases. i.e. irregularity also increase.
Graphically,
C.V%

C.V%

Drafting Doubling

Again the relation betn doubling and irregularity as

1
CV0  Where, CV0  Output CV%
N
CVm
 CV0  CVm  Input CV%
N
N = No. of doubling
That is, when doubling increases the CV% of output sliver
decreases i.e. Irregularity decreases.
Irregularity of Draw frame:
1. Periodic variation
134
 2. Drafting wave.
1. Periodic variation: A periodic variation has a constant
wave length and its amplitude is either only slightly
variable or varies so slowly along the material that it
remains fairly steady over many waves. The wave
length of a periodic variation on the frame at which it
is introduced may be between 3" for roller and 5"for a
roller period together with longer and longer waves
from latter process.
Causes of periodic variation:
 The roller nips do not always remain in fixed positions
due to top or bottom roller eccentricity, varying
compressibility of synthetic rubber etc.
 The roller do not always run at steady speeds due to
eccentricity bottom roller, eccentricity mounted gear,
wheels, inaccurately cut gears, rollers variation.
 The roller sometime slip so that the fibres under them
do mot move at the speed of the rollers due to incorrect
roller weighting, incorrect draft distribution.

2. Drafting wave: The distance betn two pairs of rollers is

dependent upon the staple length of fibre. But if there are
short fibres in sliver, they are not gripped by the rollers all the
time. So they are in a floating movement in the drafting zone.
This irregular motion of short fibres betn the pairs of rollers
gives rise to a wave like formation which is called drafting
wave.

135
Causes of drafting wave:
I) If fibres are not parallel position in carded sliver.
II) For wider roller setting.
III) Due to pressure of short fibres in sliver.

Remedies:
 By parallelization of fibres by drawing.
 By doubling of slivers.
 By closer roller setting.
 By removing short fibres.
Causes of irregularity:
1. Inherent causes:
 Random fibre arrangement,
 Variation in fibre fineness
 Length co-efficient of variation percentage high.
 If short fibre is less than nip point.
2. Mechanical causes:
 Incorrect setting of drafting roller
 Wrong distance of draft in drafting zone.
 Roller speed variation
 Roller slippage
 Improper adjustment of pressure bar on cot roller.
 Damage cot roller
 Eccentric cot roller.
 Rough calendar roller
3. External causes:

136
  Unproper temperature and relative humidity
percentage
 Lack of supper vision
 Unskilled labour
4. Properties of raw material:
 Fibre length
 Strength
 Trash percentage
 Moisture
 Crimp
 Surface character
 Maturity

Effect of irregularity:
1. Effect of yarn:
 Thick and thin place is induced on yarn
 The strength of yarn or robbing vary at different places
 Twist or unit length may also vary at different places
2. Effect of fabric
 Finishing of fabric does not uniform
 Less stable dimension
External lusture is damaged.
Irregularity drafting:
Irregular drafting increase irregular of delivery sliver
Causes:
 Incorrect top roller weighting
 Damage cot roller
137
  High vibration
 Incorrect setting of bottom drafting roller
 Faulty stop motion device
Remedies:
 Correct roller setting
 Proper weighting of top roller
 Proper draft distribution and stop motion would be
maintained.
 Replacement of damage cot roller
Roller lapping: When sliver passes through betn rollers in
draw frame, they sometime form lap with the bottom roller.
This is called roller lapping.
 For oily roller covering.
 Cracked roller surface.
 For warm roller covering.
 Impurities on the roller flutes.
 High relative humidity percentage.

Remedies:
 Roller covering should free from oil, wax etc.
 Roller surface should be plain/well burnished.
 By removing impurities from roller flutes.
 Proper control of RH%
 Replacement of damaged rollers.

Roller slip: Effect: The effect of roller slip is mostly found in

fibre/sliver irregularity. If roller slip is present, enormous
waves remain present in sliver. It means, due to roller slip
138
proper parallelization of fibres can not be achieved. This effect
is more obvious in coarser.

Causes:
 For pressure variation on top rollers.
 If thick sliver is passed through drafting arrangement.
Remedies:
 By using narrow flutted roller for better gripping of
sliver.
 By using closer setting in the middle zone.
 By keeping proper pressure on top roller.
 By alternating draft betn zone to zone.

Roller setting: The arrangement of roller between the nip

points of two adjacent pair of rollers in draw frame is called
roller setting.

Factor of roller setting:

1. Fiber staple length: When staple length then roller
gauge will be high.
2. Bulkiness of material: Bulk of material is high, setting
will be wider and vice-versa.

139
 3. Degree of compactness of input sliver: If compactness
is high, setting will be wider
4. Fibre surface characteristics: If fibre surface harsh, then
wider setting and vice-versa.
5. Draft: High draft, closer roller setting.
6. Types of roller: If metallic roller, wider setting. If
rubber roller, closer setting.
7. Machine speed: High speed, wider setting.
8. Frictional property: If frictional property of fibers is
high, then setting should be wider.
9. Machines mechanical condition: If mechanical
condition of machine is had, the setting should be
wider.
First of all, the roller setting is selected on the basis of
above factor.
If the sliver quality is bad than on trial basis, the setting of
machine should be adjusted so that the uniform sliver is
obtained.

Function of Trumpet:
 It prevents the disintegration of web.
 It minimize drafting wave.

Function of Condenser:
 The condensing of sliver enables more mtl to be fitted
into the delivery can.
 By using a lateral roller, can weight can be increased
20%
140
  By condenser, greater fibre adhesion is achieved.

Advantages of Draw frame blending:

 Blending can be performed accurately without raw mtl
variation.
 Blending of cotton with synthetic or synthetic with
synthetic can be done.
 The measuring of percentage of component raw mtl in
blended mtl can be calculated very simply by selecting
no. of slivers which will enter into the m/c
 Each raw mtl component can be processed in a drafting
arrangement of its own.

Characteristics of drawn sliver:

 Fibres are oriented to the parallel of fibre axis.
 Sliver are uniform.
 Less wt/per unit length.
 Less fibres are projected to the outer from sliver.
 No hook formed.

Carded sliver:
 Fibres are oriented at the different direction.
 Slivers are not proper uniform.
 More wt/unit length.
 More fibres are projected out from the sliver.
 Hook is present; Trailing hook and leading hook.

Difference between Carded & Drawn sliver:

141
 Carded sliver Drawn sliver
1. Fibre orientation in all 1. Fibre orientation in
direction the parallel direction
to the sliver axis.
2. Many fibres are 2. Less fibres are
projected out from projected out from
sliver. sliver.
3. Hooks formed. 3. No hooks formed;
straight
4. Irregular wt/unit 4. Regular.
length.
5. More thick. 5. Less thick.

Mathematical Problems
Problem-01: 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 = 60 gr/Yds, Efficiency
= 90%
Soln:
Feed wt
Draft (required )   Doubling
Delivery wt
Feed wt
 Delivery wt   Doubling
Draft
60  8
=  60 gr / yd
8

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 600  1.09  60  8  0.90  60  2
Production per shift 
7000
 7000 grain = 1 lb 
= 4843.33 lb  1m  1.09Yds 
 

Problem-02: Find out DCP to produce 60gr/Yd sliver from

62gr/Yd sliver if,
Delivery speed 400m/min
No of doubling 8
Draft constant 320
Soln:
Feed wt 62  8
Deliver wt  8 
Draft Draft
 Draft  8.267
Draft const
 Draft 
DCP
 DCP  37.99  38

143
 Chapter

1 Introduction
Flow chart of jute yarn manufacturing: Flow chart of jute
yarn manufacturing:

Selection of jute for a batch

Piecing up

Softening and lubricating

Pilling or conditioning

Breaker Card
Carding
Finisher Card
1st Drawing
Doubling & Drawing
2nd Drawing
3rd Drawing
Spinning

144
 Spinning

Warp Yarn Weft Yarn

Warp or Spool Cop winding

Winding

Beaming or
Dressing

Weaving

Finishing

Batch:
A blend of different types of jute is made up to suit the
particular class of yarns being spun; this blend is known as
“the batch”.
i.e. n batch the no of bales of jute is selected for making a
particular type of yarn.
For example, to produce 8 lbs/spindle Hessian warp yarn
following batch component is taken under consideration.
White C-40%---40bales
White X-40%---40bales
Tossa -20%-----20bales
Total -100%----100bales

145
Batching:
All the process form preparatory to carding includes in the
bathing. It is the primary stage of jute yarn processing.

Objects of Batching /Importance of Batching:

 To help the fibre movement freely during processing.
 To get expected dampness and flexibility.
 To reduce harness or stiffness.
 To control and reduce the yarn cost.
 To reduce waste.
 To intermix the batch component effectively.
 To produce improve graded yarn.
Defects of batching:

 Jute yarn will be hairy due to applying small amount

of emulsion to jute fiber and the jute yarn breakage will
be increased during yarn preparation and higher
wastage.
 Incase of large amount of emulsion,during processing
possibility of lapping fibres of rollers and causes
defects in processing.As a result, rollers and pins
becomes defect.
 Jute will be soft and rotten due to keeping jute in piling
fiber more time after applying emulsion.
 Jute or yarn’s strength will be reduced for mechanical
fault of softener.
 Yarn would be thin and coarse because of fluctuation
of dollop wt.
146
  Yarn quality would not be good if jute would not
spread equally in spreader and breaker.

Factors considered for Batch Selection:

 Cost of raw materials,
 Physical properties and quality of jute,
 Availability and duration of jute.
 Quality of yarn being spun.
 The processing machineries.
 Suitability of spinning and weaving.
 Customers demand.
 Cost of production.

Emulsion:
A mixture of some lubricating agents which is applied on jute
fibre to make the fibre soften and flexible.
An emulsion is an intimate mixture of two immiscible liquids
where one is dispersed in small globules on the other and
addition of a third substance brings stability. Emulsion is
made by splitting up oil into minute drops which are
prevented from reuniting in water.
General recipe:
Water -73%
Oil -25.4%
Emulsifier-1.6%

Equipment/Characteristics of good quality emulsion:

 It should be stable for certain time.
147
  It should have no bed effect on jute fibre.
 It should be colorless.
 It should have high softening capacity.
 The droplet of emulsion should be so small that it can
easily penetrate on the fibre.
 It must be odorless.
 It must be cheap and available.

Requirements of good batching oil:

 It must have no harmful effect on jute fibre.
 Its color must acceptable so that it does not stain on the
fibre.
 It must have no spontaneous combustion.
 It should not go rancid on storage.
 It must be cheap and plentiful in supply.
 It should have low viscosity.
 It should have high lubricating value.
 It should not sticky.

Function of emulsion Ingredients:

Function of oil:
 It lubricates the fibre,
 It helps free movement of fibre during processing.
 It cleans pins and rollers of the machine.
 It makes fibre soften and gives good spinning
property.

148
Function of water:
 It increases extensibility of fibre which resists fibre
breakage during processing.
 It gives sufficient dampness and flexibility.

Function of Emulsifier:
 It removes temporary harness of water.
 It helps emulsion to be in stable form.
 It makes droplet formation easier.
 It prevents separation of oil from water.
 It reduces surface tension.

Function of Urea:
 It helps easy penetration of emulsion into the fibre.
 It helps the fibre to be soften quickly.
 It reduces maturity time to half generally fibre is stored
48hrs incase of normal emulsion. When emulsion
contain Urea, it keeps maturity time 24hrs.

Recipe for Emulsion:

Water -73%
Oil-25.4% (Normal recipe)
Emulsifier -1.6%

Emulsion for CBC (Carpet batching cloth):

Water -89-91%
Oil -8-10
149
 Emulsifier -0.5-1%

For High Active Moderate recipe:

Jute Batch oil -26.45%
Water -72.85%
Urea -0.3%
Nonidient -0.4%

Faults in emulsion:
1) Creaming:
When an emulsion is prepared, it is not possible to make all
the drops exactly same size. Comparatively the larger droplets
will slowly move up to surface of emulsion as larger the
droplet lower the specific gravity in comparison of water and
forms a layer at the surface causing uneven distribution of
water and forms a layer at the surface causing uneven
distribution of emulsion. This defect is called creaming. It
increased the yarn breakage during spinning.
Creaming occurs due to
 improper oil selection and
 not accurate mixing ratio of oil, water and emulsifier
and
 bad agitation of the mixture.
Remove:

150
 i) Keeping the size of droplets as small as possible for
which a slow running paddle should be arranged into
the storage tank to stir.
ii) By using oil having high specific gravity.
iii) After making the emulsion, should not be more time
storage.

2) Breaking:
Breaking can be regarded as the opposite emulsification
where the droplets fo the internal oil phase unit form large
drops which then float to the surface of the emulsion.
Remove:
This breaking fault removed by high-speed agitation.

Requirements of emulsifier:
 It must not impair the lubricating properties.
 It should no have objectionable color and odor.
 It should be chemically inert with fibre.
 Moisture regain should be less than 30%.
 It should have good wetting properties.
Requirements of water:
 It should be soft (free from CO2, Mg, Fe etc)
 Hard water should be treated before using.
 It should be colorless and odorless.
 It should be free from suspended mineral.
 It should be acceptable.

151
Batch composition for different jute yarn/types of jute
yarn/selection technique:
1) Hessian warp:
These types of yarn are good, clean and free from
specks with high lusture. For manufacturing this type of yarn,
clean and defect free jute is required.
Bath selection:
Hand jute 70%
Soft jute 30%

For 8 lbs/spindle Hessian warp yarn:

White C –40%
White X-40%
Tossa –20%
2) Hessian weft:
Hessian weft jute should be clean and softer than Hessian
warp jute i.e. More clean fiber is required for manufacturing
this yarn. But fiber of lower strength can be used.
For light yarn:
Hard jute-50%
Soft jute-50%
For heavy yarn:
Hard jute-30%
Soft jute-70%
For 8 ½ lbs/spindles of hessian weft yarn:
White C –40%
152
 White X-40%
Tossa –20%
3) Sacking warp:
Hard jute-50%
Soft jute-50%
Sacking warp jute should be good and strong but specks do
not matter much in this case. Color is not important for
manufacturing this type of yarn. So 70 to 80% Tossa jute can
be used.
Example: X-bottom-67%
S MR-33%

4) Sacking weft:
 Low quality and coarse yarn.
 No problem of using low-grade jute.
 Sacking weft batch may contain.
i) Line cutting,
ii) Bale cutting,
iii) Soft and hard waste,
iv) Rope waste and jute dust.
v) Habizabi and tangled jute
C.B.C weft:
Tossa-- -–80%
Mesta--- -20%
Or,
Tossa ---–60%-70%
153
 White--- -–40-30%
Or,
100% Tossa jute.

Reasons of using emulsion: objects of emulsion apply:

i) To make soft fiber.
ii) To increase cohesiveness,
iii) Pliability increase,
iv) To increase flexibility,
v) To make spinning satisfactory,
vi) To make the fiber suitable for carding,
vii) To give twist and easy movement.
viii) To avoid stiffness.

Clock length:
When clock pointer moves one complete revolution
during this time feed roller feeds certain length of jute fiber.
This length is known as clock length.

Clock length = Revolution no of feed roller 

circumference of feed roller.
Clock length can be change according to our need

Dollop weight:

154
When clock pointer moves one complete revolution during
this time fixed wt of jute fiber is feed to the m/c. This fixed wt
of jute is known as dollop wt.
It always be constant for uniform feeding.
Example:
If 10 lb sliver is fed after the moving of clock pointer
through a distance of 3600. Then this 10 lb is known as dollop
wt.

Draft:
Draft may be defined as the ratio of surface speed of delivery
roller and s.s of feed roller or delivery hank and feed hank.

Surface speed of delivery Roller

Draft 
S .S . of Feed Roller
Delivery Hank

Feed Hank
Feed Tex
 Jute
Delivery Tex
Lead percentage:
The ratio of the difference between faster surface speed and
slower surface to the slower surface expressed as percentage,

Faster surface speed-slower surface speed

Slower surface speed X100

Suppose, surface speed = 21 ft/min

Surface sped of adjacent roller = 20 ft/min
155
 21  20
Lead %   100  5
20
Process flow chart of woolen yarn:
Raw wool

Scouring

Drying

Lubricating

Carding

Drawing

Spinning

156
Process flow chart of worsted yarn:
100% Virgin

Scouring

Drying

Carding

Gilling

Combing

Drawing

Spinning

157
Process flow chart of heavy /Sacking Yarn:

Root cutting

Emulsification /Softener

Pilling

Mixing with mill wastes

Teaser card

Mixing with long jute

Breaker card
Carding

Finisher card
Drawing

Spinning

158
Process flow chart of Carpet Batching Yarn / Hessian Warp
Yarn:
Bale selection Spreader Breaker Card

Finisher Card

1st drawing

Spinning Finisher drawing 2nd drawing

Difference between woolen Yarn & Worsted Yarn:

Woolen Yarn Worsted Yarn
1) Carded Yarn 1) Combed Yarn
2) Less strength 2) High strength
3) Irregular 3) Regular
4) It may be blended. 4) It never blended.

Amount of emulsion used in jute:

The amount of emulsion varies with:
i) Cost of material.
ii) Moisture content,
iii) Temperature,
iv) Humidity.

Types of jute Monsoon Dry

White/Tossa 22-24% 25-27%
Mesta 24-26% 27-29%

159
Bale cutting 37-39% 40-42%
Line cutting 28-30% 31-33%

Pilling/Conditioning:
The process by which after applying emulsion
jute fibre is stored at a specific condition for certain time is
called pilling.
Objects:
i) To soften and split up of jute fibre,
ii) To loosen the fibre,
iii) To convert the rooty material into spinnable fibre.

Required time of pilling:

Types of jute Grade Duration
Good 2days
Long jute Medium 3days
Low 4days
Cutting - 4-8days
Mesta Good 5-6days
Low 6-7days

Effect of oil content on yarn strength:

Oil content Tenacity (gm/tex)
0.0 12.2
0.5 14.0
1 14.6

160
2.5 14.4
5.0 14.5
9.0 13.9

Stainless emulsion:
If in an emulsion the oil percentage is less and water
percentage is higher than that of normal emulsion, is said to be
stainless emulsion.

To make carpet (CBC), stainless emulsion is applied.

Stainless emulsion is prepared by following recipe:

Water 92 to 95%
Oil Less than 1%
Emulsifier 0.5 to 1%
The yarn, which is made by applying stainless emulsion, is
known as stainless yarn.

Jute spreader machine

Objects:
 To comb and open the pieced out of long reeds of jute.
 To convert them into an even and continuous sliver
which receives an even application of batching
emulsion.
 To prepare ribbon like sliver.
Machine working principle:

161
  The machine consist of two sections a slow chain and a
fast chain. Jute is fed manually on the feed lattice and a
Slave pointer regulates this feeding.
 After feeding the material enters the slow section via a
pair of flutted feed roller.
 In slow section, it is carried over a slow moving gill
bed or pin bed. The fibers are pressed on this pin-bed
by 3 heavy lantern rollers. This gill bed contains 32-gill
bars.

 Then the material goes to fast section or combing

section, which is formed by a gill bed with 10-12times
faster than slow sections. Generally draft is 10.
 Then jute goes to conductor plate while emulsion is
applied on it.
 After spraying emulsion, jute is received by a roll
former in roll form.

Jute softener machine

1) Single Softener M/C,
2) Tandem Softener M/C,
3) Good Spreader M/C.
1) Single softener M/C:
Construction:
162
 These machines consist of 24-64 pairs of rollers and
these rollers are spirally flutted and jute goes through
them. A feed sheet and a delivery sheet is placed
before feed rollers and after deliver rollers respectively.
Working Principle:

 In this machine, material is fed manually on feed sheet

(6ft long).
 Then through flutted feed roller the material goes
through a series of spirally flutted rollers. Spirally
flutted rollers have right hand and left hand spiral
flutes alternative.
 After passing 1/3 area between the fed rollers and
delivery roller ,emulsion is applied over material,
which soften jute, and a tray below the machine
collects excess emulsion.
 Then through the delivery roller, the material is
delivered from delivery sheet.

Types of emulsion making machine:

1. Paddle Mixer & Agitator – (OD Batch Mixer
machine).
2. Homogenizers.

163
 3. Colloid mills.
4. Ultrasonic emulsion plant.

Emulsion preparation machine:

OD Automatic Batch Mixer:
Specification:
 Capacity of mixing cylinder: 1000 L.
 Motor:
 For Paddle (1HP)
 For emulsifier pump (Half HP)
 For oil pump (1HP)
 Volume of machine:
 Length 5 3

4
 Width 2-2
3
 Height 5-10
 Power of production:
1-6 tones/hour.

‘OD’ Batch Mixer is a simple automatic m/c for producing

stale batching emulsion for jute.
Procedure:
 The percentage of emulsion, oil and water accurately
and automatically measured by volume.
 The percentage of oil and emulsifier can be adjusted
easily by setting the pointers on oil and emulsifier
scale. When adjusted, the machine automatically adds
the required percentage of water to complete 1000 L.
164
  Once the required percentages are set, the machine will
automatically continue to measure and mix these
percentages each time.

 After all the ingredients are added, the agitator or

paddle starts to rotate at a high r.p.m. Then emulsion is
formed which is then stored to the storage tank under
the mixing tank.
Procedure of emulsion preparation:
i) Emulsifiers and equal quantity of mineral oil are
placed in the mixing tank and mixed them into a jelly
like substance.
ii) Then remaining oil is added slowly with heat applied
and agitator running (approx 35min)

165
 iii) Required amount of water is slowly added with
agitator, mixing them to the required form
(approximately 20min)
iv) When emulsification is completed then the mixture is
pumped to the gravity supply tank (approximate
20min) from where the emulsion is passed to the
softener or spreader machine through suitable
pipelines. Hot emulsion is effective well and penetrates
well into the jute fibre and gives always-good results.

Distinguish between Simple Paddle Mixture & OD Batch:

Simple Paddle Mixer “OD” Batch Mixer
1) Non automatic. 1) Automatic
2) Ingredients are manually 2) Ingredients are
measured. automatically measured.
3) Agitation is not so 3) Agitation is vigorous.
vigorous.
4) Droplet forms are of big 4) Tiny droplet forms.
size.
5) Produced emulsion’s 5) Emulsion stability is high.
stability is low.
6) Higher time consuming. 6) Less time consuming.
7) Less productivity. 7) High productivity.

Differentiate between Spreader M/C and Softener M/C:

Spreader M/C Softener M/C

166
 Spreader M/C Softener M/C
1) Presence of chain of 1) Absence of chain of
pinned bars-Slow chain and pinned bars.
fast chain.
2) Only long jute is feed. 2) All kinds of jute including
cutting is feed.
3) Easy controlling of 3) Difficult to maintain
emulsion applies. emulsion apply.
4) High maintain cost. 4) Low maintain cost.
5) Used for high quality 5) All types of yarn.
yarn.
6) Can be given draft. 6) No drafting
7) Small No. Of labor needs. 7) Higher No. Of labor
needs.
8) Emulsion is applied at last 8) Emulsion is sprayed when
after drafting. fibers have passed 2/3 of
roller.
9) Only feed and drawing 9) 25-64 pairs of rollers are
roller are flutted. flutted.

Defects of jute:
1) Rooty jute:
This defect occurs due to under rotting of the root ends of
the fibers. The root end become hard causing rooty fibers.
2) Croppy fibre:

167
 The top end of the fibers are rough black and hard due to
careless steeping for rotting. By cutting this faulty top end,
used for low quality yarn preparation.
3) Mossy fibre:
Mossy groups in stagnant water. Jute plate growing in
such places mosses adheres to the fibre causing mossy
fibre. By cutting this faulty fibre jute used for low quality
yarn preparation.
4) Knotly fibre:
Having knots in the fibers or sticky together due to
punctures in the growing plats or insect bite. Difficult to
separate the fibers from the stem by cutting.

5) Specky fibre:
If the jute fibers are not rotted and washed properly, the
barks adhere to the fibers causing them speck. Good result
will get if pilling more time after emulsion apply and
proper carding.
6) Weak fibre:
Over rotting is the main cause of weak fibre. Also due to
under drying and storing in moist condition. By mixing
this faulty fibre with strong fibers.
7) Sticky fibre:
If the top end at the jute plant is not stripped properly
from the fibre the brow pieces of the plant remain with
fibre caused this defect. It can be removed by proper
carding.

168
Gulping: (How feed regularity achieved)
This defect arises when the rate of feeding is not uniform. In
spreader machine one end of fibre is caught up in the fast
chain where as the other end is caught up slower chain. The
pressure of other fibers in the slow chain holds that fibers,
back against the action of the fast chain. If there are not
enough fibers in slow china because of not uniform feeding
then that of the fibre may more suddenly forward to the fast
chain and prevents itself being fully treated. This defect is
called Gulping.

Emulsion Stability Test:

At first take 100 C.C emulsion in a breaker. Then keep it for
24hrs. If by this time any of the defects like breaking or
creaming occurs, then the emulsion will said to be bad or
defected. Otherwise the emulsion is good.

Mathematics Problem (Emulsion)

Problem-(01):
If Raw jute receives an application of 20% emulsion of
which 15% is absorbed. Find out the weight of a batch of
12bales Raw jute (4000lbs = 1bale):
Solution:
Wt of 12 bales = 4000  12 = 48000 lbs.

169
100 lbs raw jute after batching wt = 115 lbs
115
1 lbs raw jute after batching wt =
100
115  48000
48000 lbs raw jute after batching wt =
100
= 55200 lbs (Ans)

Problem-(02):
If an emulsion is prepared as follows: Oil = 24%, Water =
74.5%, Emulsifier = 15%.
If raw jute receives an application of 20% emulsion of which
15% absorbed. Find out the absorbed amount oil, water and
emulsifier of raw jute (A batch containing 12bales,
4000lbs/bales)
Solution:
Wt of 12 bales = 4000  12 = 48000 lbs.
100 lbs emulsion contains = 24 lbs oil
24
1 lb emulsion contains =
100
24  15
15 lbs emulsion contains =  3.6 lbs oil
100

100 lbs raw jute absorbs = 3.6 lbs

3.6
1 raw jute absorbs =
100
3.6  48000
48000 lbs raw jute absorbs =
100
= 172.8 lbs.
170
Water:
100 lbs emulsion contains = 74.5 lbs water
74.5
1 lb emulsion contain =
100
74.5  15
15 lbs emulsion contain =
100
= 11.175 lbs
100 lbs jute absorbs = 11.175 lbs.
11.175
1 lb jute absorbs =
100
11.175  48000
48000 lbs jute absorbs =
100
= 536.4 lbs
536.4
= gallon.
9

Emulsion:
100 lbs emulsion contains = 1.5 lb emulsifier
1.5
1 lb emulsion contain =
100
1.5  15
15 lbs emulsion contain =
100
= 3.225 lb emulsifier

100 lbs raw jute absorbs = 3.225 lb emulsifier

171
 3.225
1 raw jute absorbs =
100
3.225  4800
48000 lbs raw jute absorbs =
100
= 10.8 lb emulsifier.

Problem-(03):
A jute spreader machine is running with following
data:
Dollop wt = 1000 lbs, Cluck gearing const = 10, Clock charge
pinion = 20T. Draft const = 350, DCP = 35T, Emulsification
applied = 25%. Feed wt in lbs/100yds? Delivery wt/100yds ?
Solution:
Clock length = clock gearing const  clock
change pinion
= 10  20 = 200 Yds.
Feed mt count/wt of feed jute in lbs/100Yds
1000
=  100  500 lbs/100Yds.
200
Draft.Const 350
Draft =   10
DCP 35
25
Emulsion applied =  500  125 lbs/100Yds.
100
After application of emulsion wt of Total feed material =
(500+125)= 625 lbs/100Yds
Feed material wt 625
Delivered Sliver Weight =   6.25
draft 100
lb/100Yds
172
Problem-(04):
Find the production in lbs/hr of S. M/c delivered
speed = 60 yds/min, Draft = 12, Efficiency = 80%, emulsion
applied = 20%. Wt of feed material = 6 lb/yds.
Solution:
Production in lbs/hour =
6 100  20
 60  60   0.8
12 100
= 1728
Problem-(05):
Production of spreader M/C have dollop wt = 36lbs,
Clock length = 6yds, delivery speed = 60yds/min, M/C draft
= 12, emulsion applied = 12%
Solution:
Production of spreader machine in lbs/hour =
delivery speed  dollop wt

draft  clock lenght
36 100  12
= 60  60  
12  6 100
= 2016 Yds/hr.

173
 Chapter

2 Carding
Carding:
The process by which long reeds of jute while passing through
high speed pinned rollers are broken down into an entangled
mass and delivered into the form of ribbon of uniform weight
per unit length is called Carding.

Jute can not be speed in reed or strick form. During carding

the network structure is broken and a thin web of separate
fibers is obtained which is condensed into a sliver.

Objects of Carding:

174
  To break down and split up the fibre.
 To make the sliver of uniform wt per unit length.
 To remove dirt and dust.
 To individualize and parallelize the fibre.
 To straighten the fibre drafting.
 To reduce wt per unit length.
 To mix different qualities of jute.

Classification of Carding machine:

According to Cylinder function:
1) Half Circular.
2) Full Circular.

1) Half Circular:
In half-Circular Cards jute travels the half-way round the main
cylinder in its journey from the feed to the delivery. Thus the
feed and delivery are approximately 1800 apart.
Example; Breaker Card.

2) Full Circular:
175
In this machine jute travels almost full way round the main
cylinder in its journey from feed to delivery. Thus the feed and
delivery are almost side by side, nearly 3600 inside the
machine.
Example: Finisher Card.

According to Striking:
1. Up Striking.
2. Down Striking.
1. Up Striking:
In this machine the pins of the cylinder approach the feed
from under neath and strike up the fibre. Up striking cards are
sued for low quality jute as the dirt and short fibers can not be
collected below it can again mingled with the fibers. Here fibre
loss is low.

176
2. Down striking:
In this machine the cylinder pins approach the feed form the
top and strike down into the fibre. Down striking cards are
used for high quality jute. The dirt and short fibers are
collected below and they can not mingle with the fibers again.
But here the rate of fibre loss is high. Pins of down striking
cards are thick.

According to processing:
1. Mono carding machine.
2. Dual carding machine
3. Tandem carding machine.
1. Mono Carding machine:
When a single carding machine with one cylinder is sued for
carding, its is called Mono carding machine. It is used for
cotton, not successful for jute.
177
2. Dual carding machine:
When two individual carding machine i.e. breaker card and
finisher card are used in carding, they are called dual carding
machine. It is used for jute processing.

3. Tandem carding machine:

When tow carding machines are used at a combination then it
is called Tandem Carding machine. The motion is transferred
from 1st machine to the 2nd machine. When one machine stops
the other stops automatically. It is sued in case of Roller
spinning in Cotton.
In tandem carding machine, two individual cards make up a
unit. The doffer of the 1st card feeds fibre material to the taker-
in of the 2nd card. Double carding of the raw material has a
positive effect on quality and on blending. However the
advantage is obtained at high cost hardware and maintenance.
Again additional space is required for tandem card. About 1%
cotton is processed with tandem cards now. Modern cards are
considered as a tandem of the latest generation.

According to Roller and Flat:

1. Stationary flat card:
In which the flats on the cylinder are fixed and
cylinder moves.
2. Revolving flat card:
In which the flats on the cylinder are moving and
cylinder moves.
178
 3. Roller card:
Breaker card, Finisher card, not flat.

Breaker Carding Machine:

Breaker Cards are generally down striking and half-
circular. In this machine the primary function of jute carding is
done by the action f worker and cylinder and the cleaning
actions is done between worker and stripper. It is called
Breaker Card because it breaks up to the long reeds of jute.
The main three functions of breaker Card are:
 Individualization of fibre.
 Drafting of fibre.
 Sliver formation.

Main parts:
i) A main cylinder
ii) Shell
iii) Flutted feed Roller
iv) Pin feed Roller
v) A pair of Stripper
vi) A pair of worker
vii) A pair of tin cylinder
viii) Doffer
ix) Drawing Roller
x) Delivery Roller
Working principle:

179
 1) The Roll of 6-8 spreader slivers are feed on to the feed
sheet from a creel at floor level towards the feed roller
of the breaker card.
2) The jute now enters the machine through shell feed.
This consists of a pin feed Roller and a cast iron shell.

Fig: X-Sectional diagram of Breaker card m/c

3) The jute enters the space between the pin feed Roller
and the shell and travels towards the swift moving
pins of the main cylinder.
4) When the feeding ends of the reeds meet these fast
moving pins, they are split, opened out and converted
into a fibrous beard.
5) When jute fibers come in untact with the slow speed of
the workers which gives carding action together with
cylinder but not stripping.
6) The back pointing pins of the worker opposes cylinder
pins, point against point to catch up loose fibers and at
the same time open out and card the fibre.

180
 7) The fibrous raw striped by the workers are carried
round with them and ultimately stripped by pins of the
faster running stripper roller.
8) The wastage is then discharged through the tin
cylinder.
9) In this way, jute passé 1st ad 2nd worker-stripper pairs.
10) After leaving the 2nd worker-stripper pair fleece of
fibers meet the doffer which stripes jute off the
cylinder.
11) Then the fibs pass through drawing Roller into V-
shaped condenser.
12) The fibers are delivered to delivery roller and delivery
processing roller.
Finally the sliver obtained in the roll form.

Speed of Breaker Card & pin angel & setting:

1) Cylinder – 2400 to 2700 ft/min
2) Feed Roller – 9 to 14 ft/min
3) Worker – 35 to 50 ft/min
4) Stripper – 300 to 500 ft/min
5) Doffer – 75 to 95 ft/min
6) Drawing rollers – 150 to 200 ft/min

Pin density:
Pin angle Fine yarn Coarse yarn
1. Cylinder 70-750 3 2.5
2. Feed Roller 50-800 4 3

181
3. Worker 30-350 5 4
4. Stripper 35-400 5 4
5. Doffer 30-400 6 4


1
1. Pin feed Roller and Shell =
2
2. pin feed roller and cylinder = 16 W.G
3. Cylinder and 1st stripper = 14 W.G
4. Cylinder and 1st Worker = 10 W.G
5. 1st worker and 2nd stripper = 14 W.G
6. cylinder and 2nd worker = 11 W.G
7. 2nd stripper and 2nd worker = 14 W.G
8. cylinder and doffer = 16 W.G

Finisher Card:
Finisher card is full circular and down sticking card. After jute
is processed by breaker card, it is sent to finisher card. The
rollers and cylinder are pinned in the same manner as in
breaker card but pins are finer and set closer together in
Finisher Card Machine.
Main Parts:
i) Feed sheet
ii) Pin feed roller
iii) Feed stripper
iv) Top feed Roller
v) 4-worker Rollers (1st,2nd,3rd,4th)
vi) 4-stripper Rollers (1st,2nd,3rd,4th)
vii) 2-Doffers (Top and Bottom)
182
 viii) a main Cylinder
ix) 2-pairs of drawing Roller (Top and
bottom)
x) a pair of delivery Roller
Working Principle:
 10-12 slivers obtained from breaker Card are places
side by side at the fed end of finisher card.
 Two types of feed system such as shell feed system and
double pinned fed system.
 Shell fed used for sacking weft cards and light carding
loading is possible in double pinned feed.
 The fibers come in contact with top feed Roller, pin
feed Roller and feed stripper. Pin feed Roller an feed
stripper have pins point against back and only small
amount of carding action takes place here.

Fig: X-Sectional diagram of Breaker card m/c

183
  Then the fibre transfer to the worker. The pin direction
between the cylinder and worker is pint against pint
and cylinder speed is quite higher than the worker.
Here carding action takes place.
 When the fibers are combed between workers a
stripper the stripper takes the fibre forward to the
cylinder surface it to the coming second worker-
stripper. Here the fibers are thinned down and
individualized.
 The same action is repeated along the 2nd, 3rd and 4th
pair of worker and stripper.
 While leaving 4th pair of worker-stripper the fibers
come to the action of doffer where the fibre is received
and combing action tables place since the pin direction
of doffer and cylinder is opposite.
 Then the fibre are passed through drawing Rollers and
are transferred to the 2nd doffer and drawing Roller
and delivery Roller.
Finally the finisher sliver is condensed to delivery in Roll
form.
Speed of Breaker Card & pin angel & setting:
1. Cylinder = 2400-2800 ft/min
2. feed Roller = 10-15 ft/min
3. worker = 30-40 ft/min
4. stripper = 300-500 ft/min
5. Doffer = 75-100 ft/min
6. Draiwng Roller = 150-200 ft/min
7. Delivery Roller = 150-200 ft/min.

184
Setting:

1. Cylinder and top feed Roller = 1
8
2. Pin feed Roller to cylinder = 10 W.G
3. Top feed Roller to Pin feed Roller = 10 W.G
4. Feed stripper and Cylinder = 16 W.G
5. Feed striper and Pin feed Roller = 16 W.G
6. Cylinder and Stripper-1 = 16 W.G
7. Cylinder Worker-1 = 12W.G
8. Stripper-1 and Worker-1 = 16W.G
9. Cylinder an Stripper-2 = 17W.G
10. Worker-2 and Cylinder = 14 W.G
11. Stripper-2 and Workder-2 = 17 W.G
12. Stripper-3 and workder-3 = 18W.G
13. Worker-3 and cylinder = 16 W.G
14. Stripper-4 and stripper-3 = 18 W.G
15. Stripper-4 and Cylinder = 19
16. Worker-4 and Cylinder = 17
17. Stripper-4 and worker-4 = 19
18. Doffer-1 and cylinder = 16
19. Doffer-2 and cylinder =

1
20. doffer-2 and delivery pressing Roller =
4

Distinguish between Breaker Card and Finisher Card:

Breaker Card Finisher Card
1. It is half circular carding 1. It is full circular carding
machine machine
2. It has single doffer. 2. It has double doffer.

185
3. It has two pairs of worker 3. It ahs four pairs of worker
and stripper. and stripper.
4. Less pin density. 4. More pin density.
5. Pins are coarser and set 5. Pins are finer and set closer
wider. together.
6. More production (600-650 6. Less production (400-475
lb/hr) lb/hr)
7. Wider Setting 7. Closer setting
8. Doubling is not done here. 8. Doubling is done here
9. Sliver wt per unit length is 9. Sliver wt per unit light is
high. low.

Difference between Cotton Carding and Jute Carding:

Cotton Carding Jute Carding
1. Feed materials is nep. 1. Feed materials is long reeds
of jute.
2. One carding machine is 2. Twice Carding machine is
used. used. i.e Breaker Card and
Finisher Card.
3. It removes dirt, dust and 3. It breaks down and split up
neps. of the fibre.
4. It is easy process. 4. It is difficult process.

Why two types of Carding machine used:

Breaker card only open out the fibre and remove dirt and dust

186
Breaker sliver obtained from breaker card are not complete
free from defaults and trash, dirt, dust, foreign matters are
present in Breaker Sliver. Another carding machine is required
to remove faults i.e. dirt, dust, trash and parallelizing of the
fibre. To perform this function, another carding machine
which is used is finisher carding machine.

Factors which influence carding:

Modern trends and developments of carding:
1) Pin density:
The more pin density of rollers the more carding action
and less pin density will give less carding action.

2) Cylinder speed:
Greater cylinder speed will give more carding action.

3) Fed load:
The more feed load, carding will be bad but if feed
load become lighter, carding will be better. Because
small amount of feed material will be treated by the
rollers property.

4) Sped of feed Roller:

Slower speed of feed Roller gives more carding due to
feeding of less material into the machine per unit time.
But faster speed will give reverse effect.

5) Worker speed:
187
 If worker speed is high carding will be low and again
higher pin density on worker will give more carding
action.

6) Stripper speed:
Speed of stripper has no effect on carding action. But
when stripper speed is high, good stripping will be.

7) Roller setting:
If the rollers are setting more closely then the carding
action may be high.

8) Carding ratio:
S .S .of .cylinder
Carding Ratio =
S .S .of .wor ker
The more carding ratio, the more carding action.

9) Carding efficiency:

Carding efficiency:=
S .S .of .Cylinder  S .S .of .Wor ker
 100%
S .S .of .Cylinder
More carding will be increase of more carding
efficiency.

10) Delivered Sliver:

188
 Dollop.wt
Delivered Sliver =  100%
Draft  Clock .lenght

Effects of Carding Condition on Fibre Quality:

1) Pin density of Cylinder:
Pin density has no significant effect on fibre quality.
Since the pins are set in same column and the speed of
cylinder is very high, breaking or splitting of the fibers
is not greatly influenced even when some pins are
missing.
2) Cylinder speed:
Cylinder speed is generally very high than the worker
and stripper speed. High speed of cylinder required for
carding action but if the speed is too high, carding
action becomes irregular.
3) Draft:
The greater the draft the more fibre breakage takes
place. So draft should be kept low for greater fibre
length. Draft should be such that fibre length 7-7.5cm is
produced.

4) Feed Roller Speed:

Surface.seed .ofDelivery.Roller
Draft =
Surface.speed .of . feed .Roller
When the surface speed of feed Roller decreases, then
carding action becomes good. But when feed speed is

189
 high, the drafting action is high and the rate of fibre
breakage is high.

5) Surface speed of worker and stripper:

When surface speed of worker high, then carding
action becomes low. When surface speed of stripper is
high, good striping action takes place due to good
centrifugal force.

6) Pin density:
Pin density is defines as the no of pins per square inch.
7) Shell setting:
Jute enters the breaker card through a shell feed.
This consists of a pin feed Roller and a cost iron shell.
This has a sharp edge over which jute must pass. The
setting between shell and pin feed Roller is shell
setting.
Effect of shell setting on Yarn properties:
If the distance is greater, they will grip the jute lightly and jute
will grip the jute lightly and jute will be dragged easily.
Whereas closer shell setting will result in poor quality yarn if
jute fibre length short. The following table shows the results of
experiment where yarn quality is examined by two different
shell setting.
Yarn properties Shell setting

190
Name of the Unit  
3 1
property
8 2
Yarn count Lb/spindle 7.9 7.4
Yarns breaking Lbs 7.2 7.5
load
Coeffecint of % 18.3 17.9
variation of
Breaking load
Strength Lbs 3.2 3.5

Breaker draft on fibre

Draft Feed speed Average fibre length (inch)
ft/min
24 8.1 Jute-A Jute-B
14 11.2 2.4 2.7
12 16.3 2.6 2.7
2.7 2.9

Function of cylinder:
i) To take the jute fibre form feed Roller so that
machine do not jam due to excess jute.
ii) To open out the fibers.
iii) To take the fibers from stripper.
Function of worker:
i) To take the fibers from cylinder
ii) To open out and card the fibre.
iii) To remove waste, trash, dirt and dust.

191
Action in carding machine:
1) Carding action:
i) Between worker and cylinder:
 Pin direction is opposite.
 Direction of rotation opposite.
 Speed of cylinder is higher than that of worker.

Fig: Carding action

ii) Between cylinder and doffer:
 Pin direction opposite.
 Rotation direction same.
 Speed of cylinder is higher than that of doffer.

2) Stripping Action:
i) Between Worker and Stripper:
 Pin direction same,.
 Rotation direction opposite,
 Speed of stripper is higher than worker.

192
 Fig: Stripping action
ii) Stripper to Cylinder:
 Pin direction same,
 Rotation direction same,
 Speed of cylinder is higher than stripper.
Entity: Fibers come form the plant are connected adhesion or
breaching. On carding, this mesh is broken into fragments
each comprising several fibers. Subsequent processing
simplifies these some what although even in the yarn this are
still multiple fibre.
Entities structure:
 Longer entities are coarser.
 Longer filaments are coarser,
 Longer entities are complex but not much shorter
entities.
 The simplest entities are obtained form the coarse
filament jute.

Energy balance for raw jute carding:

The amount of work expended on jute at the feed of a breaker
card is about 6watts hr per pound of jute. This work is applied

193
to the fibre to achieve several purposes which may be as
follows:
 Transverse breaking of jute.
 Longitudinal splitting of free the fibre junctions.
 Acceleration of fibers to cylinder velocity.
 Over coming friction between fibers and staves.
 Over coming friction between fibers and pins.

Different change in Pinion:

1) Cylinder change pinion:
It acts as a driver pinion. If the cylinder pinion is
bigger, then increase feed speed, so production will be
high.

2) Draft change pinion:

Draft change pinion acts as a driver of feed Roller. If
D.C.P is bigger, then increase feed Roller speed
decrease draft but production will be high.
3) Worker change pinion:
Worker pinion acts as a driver of worker roller. So if
the worker pinion is bigger then worker roller speed
will be increase. But carding will be less.

4) Doffer change pinion:

If DCP is bigger, then speed of doffer will be high and
smaller low.

194
 Mathematical Problem

Problem (01):
Calculate the wt in lb/100Yds sliver from the data:
Dollop wt = 30 lbs, Clock length = 12.9Yds, Draft = 11.23.
Evaporation loss = 4%.
Solution:
Delivery sliver wt per 100 Yds =
Dollop.wt 1 100  4
   100 lbs
Clock .lenght Draft 100
30 1 96
=    100
12.9 11.23 100
lbs
= 19.88 lbs.

Problem (02):
Calculate production per hrs from the data: Feed Roller
Speed = 18 ft/min, Dollop wt = 30 lbs, Clock length =
19.5Yds, Waste = 4%. Efficiency = 85%

Solution:

18 30 100  4
Production per hr =  60  0.85   lbs/hr
3 19.5 100
= 451.93 lbs/hr

195
Problem (03):
A breaker card is set to work with a clock length fo 12.9
Yds and a draft of 12 in the machine. If the dollop wt is 30
lbs. What will be the wt of delivered sliver in lbs/100Yds.
Solution:

Dollop.wt 1
Sliver delivered per 100 Yds =   100
Clock .length Draft
lbs
30 1
=   100
12.9 12
= 19.38 lbs

Problem (04):
Calculate the wt of sliver in lbs/100Yds delivered form the
finisher card from the data:
B/C delivered sliver = 24 lbs/100Yds
F/C draft = 15
F/C doubling = 12
Waste loss = 4%
Solution:
Wt of F/C delivers sliver/ Sliver delivered per 100 Yds
from F/C
=
Doubling 100  waste %
B / C.delivered .Sliver   100
Draft

196
 12 100  4
= 24  
15 100
= 148.432 lbs.

Problem (05):
Calculate wt of sliver in lb/100Yds delivered from the
F/C B/C dollop wt = 32 lb, B/C Clock length = 12.5 lb,
B/C draft = 10, F/C doubling = 12, F/C draft = 15.

32 1
Sliver delivered per 100 Yds from B/C =   100
12.5 10
= 25.6 lbs/100
12 100  4
Sliver deliver from F/C = 25.6    19.66 lbs
15 100

Problem (06):
how many ends at the feed of the finisher card are
required to obtain 14.22 lb/100Yds sliver from finisher
card with F/C draft = 15, B/C sliver production = 20
lb/100Yds. . M.R. = 3%
Solution:
Sliver delivery from F/C in lbs/100Yds
= delivery from B/C in lbs/100Yds
F / C.doubling 100  loses
 
F / C.draft 100
F / C.doubling 100  3
 14.22  20  
15 100

197
 14.22  15  100
 F/C doubling = = 10.44  11
20  97
11 ends will be required.

Previous Year
Questions
University of Dhaka
B.Sc. in Textile Technology, Part-II, Exam-2006
Sub: Yarn Manufacturing Technology I
Time: 4 Hrs Full marks: 80

(Answer any eight questions at least two from group-B)

(Group-A)
1. a) What is Bale Management? Why Bale Management is
done in cotton spinning mill?
b) Describe in details the characteristics of cotton fibres that
are considered by spinner.
[3+7=10]
2. a) How opening and cleaning operation is done through Blow
room?
b) What type of wastage generally produced in Blow room
and Carding?
c) How the B/Room and carding wastage can be controlled.
[4+2+4=10]
3. a) Describe the working principal of foreign fibre extractor.
(The vision shield)
b) Why a good mixer or blender m/c is essential in cotton
blow room line.
c) The trash control of feed cotton fibre is 3% After passing
the beater 2% waste is extracted, of which 15% is good
fibre. What is the cleaning efficiency of this beater.
[5+2+3=10]

198
4. a) What is the advantage and disadvantage of chute feed
system?
b) Describe the safety measurement are used in Blow room.
c) Calculate the production per hour of Blow room if-
Speed of bottom calendar roller = 8 m/min
Dia of Bottom calendar roller = 18 cm
Lap hank = 0.0011 Ne
Efficiency = 80%
No. of Scutcher = 4
[3+3+4=10]
5. a) Discuss the function of cylinder, flat and doffer of
revolving flat carding m/c.
b) Write the advantages and disadvantage of forward and
back ward movement of flat.
c) Calculate the production/hr in Kg of 8 carding m/cs if the
feed speed in 2 m/min and the hank of produced sliver is
0.15 Ne. Efficiency and draft re 90% and 100 respectively.
(Assume 4% waste extraction)
[3+2+5=10]
6. a) Describe the effect of doubling and draft in drawframe.
b) How many types of autoleveller is used in D/F? Describe
one of them with sketch.
c) Find out the draft required in D/F if Feed sliver weight =
75 grain/yd, delivery sliver weight 70 grain/yd and
doubling = 8
[3+5+2=10]
7. a) Briefly write about the task of drawframe.
b) What are the factors influence on draft of a draw frame.
c) Describe 3-over-4 roller drafting arrangement.
[3+2+5=10]
8. Short note (any four)
(a) Ginning and faults of ginning.
(b) Difference between coarse and fine cleaning m/c.
(c) Carding segment or fixed bar.
(d) Card clothing.
(e) Calculation procedure the bore size of a trumpet.
199
 [42.5=10]

(Group-B)
9. a) Write the flow chart of Jute yarn manufacturing.
b) What are batch and batching? What are factors considered
for good batch selection.
c) Write about the grading system of jute fibre.
[3+4+3=10]
10. a) Define emulsion? Why emulsion is used in jute fibre?
b) Write the characteristics of good quality emulsion.
c) A finished jute yarn contains 2% oil. During processing
20% emulsion is applied of which 16% is absorbed by jute
fibre. Calculate the % of oil given in emulsion recipe.
[3+3+4=10]
11. a) Discuss in briefly the objective of jute Breaker Card m/c.
b) Write the speed and pin angle of different roller of Breaker
Carding m/c.
c) What is dollop weight and Clock length. Why and how
dollop weight is strictly controlled in jute breaker card
m/c.
[2+4+4=10]
12. a) Give the classification of jute card.
b) Write down the difference between breaker card and
finisher card.
c) Find out the production per hour 6 carding m/c from the
following data:
Surface speed of feed roller = 3 yds/min
Clock length = 12 yds
Dollop wt = 20 lbs
Efficiency = 80%
Wastage = 5%
[2+3+5=10]
---x---

200
 University of Dhaka
B.Sc. in Textile Technology, Part-II, Exam-2005
Sub: Yarn Manufacturing Technology-I
Time: 4 Hrs Full marks:
80
(Answer any eight questions taking at least 2 from group B)
(Group-A)
1. a) What is Blow room? Write about the operation involves in the
Blow room.
b) “For export oriented knit yarn bale Management is
essential”- Explain.
c) The trash content of cotton fed to a beater is 3%. The waste
extraction is 1.4% of which 90% is trash. What is the
cleaning efficiency of the beater?
(4+3+3=10)

2. a) Write down the features of a modern high speed card.

b) Differentiate the metallic end flexible card clothing.
c) What type of the auto leveling is used in modern carding?
How it works?
(2+4+4=10)

3. a) Write down the process flow chart of combed yarn production

mentioning input and output product of each stage.
b) Write down the properties of fibre which are considered for
cotton spinning.
c) What is cotton grading? Write about the importance of
cotton grading.
d) Write some faults in cotton ginning.
(3+3+2+2=10)

4. a) Describe automatic Bale Opening machine.

b) Why Multimixer is used in cotton Blow room line.
c) Calculate production/hr of a Blow room line if
201
 RPM of Bottom calendar roller = 14
Dia of Bottom calendar roller = 18 cm
Lap hank = 0.0012 Ne
Efficiency = 80%
No of Scutcher = 2
(4+2+4=10)

5. a) Write about the Basic requirement of drafting arrangement.

b) Describe different types of drafting roller.
c) Indicate how much pressure used in different drafting rollers
of cotton draw frame.
d) Find out the drawn sliver hand in Ne if card sliver weight is
3.85 gm/yds, draft and doubling are 8.5, 8 respectively.
(2+4+2+2=10)

6. a) What is roller setting? Discuss the factors considered for roller

setting.
b) Describe with diagram a auto leveling equipment for
modern cotton draw frame.
c) What is Apron? Why apron is used in modern drafting
arrangement?
(3+3+4=10)

7. a) Show the difference between modern high speed Draw Frame

and traditional Draw Frame.
b) What happened in the yarn and fabric if sliver is irregular &
how can we overcome this problem. Describe in details with
sketch.
c) Write down the importance of condenser and trumpet.
(3+5+2=10)

8. Write short notes on any four:

(a) Bale management. (b) Mixing and Blending. (c) Feed
regulating motion.
(d) Carding segment. (e) Pneumatic measuring device for auto-
leveling.
202
 ( 2.5  4 =10)

(Group-B)

9. a) Show the flow process of CBC yarn.

a) Write down the jute fibre properties.
b) What are the differences between jut and cotton fibre?
(3+4+3=10)

10. a) Describe the working principle of jute spreader machine with

sketch.
c) Why pilling is needed? How it is done?
d) Write down the importance of batching.
(5+3+2=10)

11. a) Define dollop weight and clock length.

e) Give the classification of jute card.
f) Draw a cross-sectional diagram of Breaker card machine and
mention speed, pin angle and settings.
(2+3+5=10)
12. a) What is shell setting? What are the effects on fibre properties
of shell setting.
g) Write the differences between breaker Card and Finisher
Card machine.
h) Find out the production per hour per machine of a Breaker
card machine from the following data-
Surface speed of feed roller – 18 feet/min
Clock length – 12 yds
Dollop weight – 25 lb
Efficiency – 85%
Wastage – 5%
(3+2+5=10)
---00000000000---

(Chapter wise questions)

Introduction
203
 1. Write down the process sequence of combed yarn
production. (2:01)
2. Write down the process flowchart of combed yarn
production mentioning input and output product of each
stage. (3:03) (3:04)
3. Define: Mixing and Blending. (2:01) (2:02)
4. What do you mean by fibre fineness and maturity? Why are
they important for spinners? (4:00)
5. What do you mean by fibre strength and maturity? Why are
they important for spinners? (4:04)
6. Write down the process sequence of 30 Ne carded yarn.
(00:2)/ Write down the process sequence of 30 Ne carded
yarn by indicating the name of input and output product in
each stage. (2:02) (5:04)
7. Describe the factors which influence on opening and
cleaning action. (3:02)/ What are the general factors
influencing open & cleaning. (2:04)
8. Briefly describe the fibre properties that influence the yarn
quality. (5:02s)
9. Differentiate between carded and combed yarn. (4:02s)
10. What do you mean by Bale management? Why it is
necessary for cotton yarn production? (3:02s)/ What do you
mean by Bale management? Why it is important for knitted
yarn production? (3:04)
11. Write down the properties of fibre which are considered for
cotton spinning. (3;04)
12. Explain how fibre properties influences yarn quality. (3:03)

Blow room
1. Discuss the working principle of Axi-flow cleaner with
sketch. (4:02) (4:04)
2. What is cleaning efficiency? (2:04)

204
3. Illustrate the working principle of Blendomat with sketch.
(3:02s)
4. Describe the different type of beater used in modern blow
room line for processing 3% trash in raw cotton. (3:03)/
Describe the different type of beater used in modern blow
room line. (4:01)
5. Show the line diagram of modern Blow room line for
processing 3% trash in raw cotton. (4:03)
6. Find the production in kg/day of a blow room line with
4(four) scutcher. If,
Calendar roller dia-7
Calendar roller rpm-12
Efficiency-90%, waste-4% and lap wt-14 ozs/yd.(3:03)
7. Find the production in kg/day of a blow room line with
4(four) scutcher. If,
Calendar roller dia-7
Calendar roller rpm-12
Efficiency-70%, waste-4% and lap wt-14 ozs/yd.(4:04)
8. Why multimixer is used in Blow room line? (2:03)
9. Describe regulating motion present in modern blow room
line. (4:03)(3:02)
10. What do you mean by feed regularity? How many types of
feed regualating motion are used in blow room. (3:01)
11. How dust is removed from blow room? (2:03)
12. Draw the figure of Axi-flow cleaner. (2:03)
13. Write down the working principle of multimixer m/c for a
modern blow room with neat sketch. (4:03)
14. Write down the working principle of a Blow room machine
used for both opening and cleaning. (4:02s)
15. Describe a modern blow room machine used for cleaning of
trashy cotton. (4:03)
16. Describe a modern mechanism used for air cotton separation
in Blow room machine. (4:03)
205
 17. Write down the working principle of multimixer m/c for a
modern blow room with near sketch. (4:03)
18. What is the main object of blow room line? (1:02) (1:00)
19. Show with a line diagram of a modern blow room line for
processing 40Ne combed yarn with 2.5% trash in cotton.
(4:00)
20. Show with a line diagram of a modern blow room line for
processing 80Ne combed yarn with 2.0% trash in
cotton.(4:01)
21. Write down the function of a piano feed regulatory motion.
(3:00)
22. Describe the function of different types of grid used in blow
room line. (2:01)
23. Draw the sketches of grid bars used in blow room. (2:00)
24. Comments on effects if we increase, beating points in blow
room line in case of long staple low trash contain cotton.
(2:00)
25. How dust and metal are removed in Blow room? (3:02)
26. State the common faults found in Blow room. (3:02s) (4:00)
(3:02)
27. State the common faults found in Blow room. How it can be
eliminated? (3:01)
28. A sudani cotton with 6% trash was processed in a Blow
room and then in carding m/c which produces sliver
containing 0.4% trash of the cleaning efficiency of carding
m/c is 75% Find out the cleaning efficiency of the blow
room line. (4:00)
29. What are machine used in blow room? (2:04)
30. Describe the associated equipments used in modern blow
room line. (5:02)
31. Describe the safety devices used in Blow room line. (3:02s)
32. Find out beats/inch from the following particulars-
Beater rpm: 720
206
 No of striker: 16
Feed roller rpm: 24
Dia of feed roller: 3 inches (3:02)
33. The trash content of cotton fed into a beater is 3% the waste
extraction is 1.45% of which 8.5% is trash. What is the
cleaning efficiency of the beater? (3:02s)
34. The trash content of cotton fed into a beater is 3% the waste
extraction is 1.45% of which 3.5% is trash. What is the
cleaning efficiency of the beater? (3:04)

Carding
1. Draw and indicate the parts of a chute feeder in carding m/c.
(3:01)
2. Describe the function of chute feed system with diagram.
(4:03)
3. What are the functions of cotton carding? (2:04)
4. How cotton are individualized by carding action. (3:03)
5. What will happen if we increase the speed of doffer and
taker-in: (3:03)
6. How taker-in speed influences on yarn quality? Discuss the
diagram. (5:00)
7. What is the function of flats in carding? (2:00)
8. Distinguish between carding action and stripping action with
diagram. (4:02)
9. Write the important factors of card clothing selection. (3:00)
10. Give a brief description about the different types of card
cothing. (5:04)
11. What are the advantages and disadvantages of metallic card
clothing over flexible card clothing. (3:00)
12. Differentiate between flexible and metallic card clothing.
(4:02) (4:02s)
13. Show the grinding and mounting schedule of modern card.
(4:01)
207
 14. What happens when Barrow wheel and DCP is increased.
(2:02)
15. Write down the name of waste produced in carding machine.
(2:02)
16. What is carding angle? Sate the caring angel of taker-in,
cylinder, doffer and flat of revolving flat card machine.
(2:02s)
17. Why carding is called the Heart of spinning? (2:02s)
18. Why auto leveler is important? (2:04)
19. Write down about the auxiliary equipment of cotton carding.
(2:04)
20. Write down the recent development of cotton carding. (1:04)
21. Describe the auto-levelling equipment working principle
with diagram. (5:03)
22. Explain pneumatic measuring device used for card auto
leveling. (2:03)
23. Write down the principle of long-term auto leveling. (2:04)
24. What are the factors considered for selection of card
clothing. (2:02)
25. Write down the objects of carding. (2;01)
26. Draw the cross sectional diagram of a modern carding
machine and indicate its component. (-:01)
27. What are the characteristics of carded sliver? (2;01)
28. What are the additional carding systems used in modern
carding machine and why? (2:01)
29. Draw the sketch of modern card by showing the important
gauge points for medium trashy cotton. (4:01)
30. Lap weight is 1lbs/yd and sliver hank is 0.11 Ne. Find out
the draft of a carding m/c. (1:00) (5:04) (2:02)
31. A carding m/c was running with following particulars-
Rpm of feed roller = 1.5; rpm of doffer = 10; dia of doffer = 27
inches; dia of feed roller = 2.25 inches. Find out the mechanical
draft. (3:00)
208
32. Find out the draft of carding machine if the lap weight is 500
gm/meter and the sliver hank is 0.12. (2:01)
33. A modern spinning mill has 10 card. It runs 3 shift/day. Find
out the production per day in Kg from the following data:
Delivery speed: 220 meter/min
Doffer dia: 27 inch
Delivery sliver wt: 70 grains/yd
Card efficiency: 95%
Dia of feed roller – 2.25 inch (4:01)
34. A modern spinning mill has 10 card. It runs 3 shift/day. Find
out the production per day in lb from the following data:
Delivery speed: 220 meter/min
Doffer dia: 27 inch
Delivery sliver wt: 68 grains/yd
Card efficiency: 95%
Dia of feed roller – 2.25 inch
Tension draft – 1.1, Waste- 3% (4:02s)
35. A modern spinning mill has 10 card. It runs 3 shift/day. Find
out the production per day in lb from the following data:
Delivery speed: 220 meter/min
Doffer dia: 27 inch
Delivery sliver wt: 68 grains/yd
Card efficiency: 95%
Dia of feed roller – 2.25 inch
Tension draft – 1.1, Waste- 5% (4:02)
36. The output speed of coiler calendar roller is 4210 m/min
with lap roller advanced the lap sheet at 51 cm/min calculate
the mechanical draft, actual draft of the machine, assuming
the 5% waste in card. (3:03)
37. Find out the sliver hank of a carding machine for the
following data-
Lap weight: 14 ozs/yd
Draft: 100
209
 Waste: 4% (5:04) (2:02)

Draw frame
1. What are the main objects of modern draw frame? (2:04)
(2:01)
2. Describe the mobern drafting systems used in cotton draw
frame. (5:01) (4:02s) (4:04)
3. What are the effect of roller slip? What are their causes and
remedies? (3:02s)
4. What are the function of condenser and trumpt in Drawing
frame. (3:04)
5. Write down the factors influences the draft in a Draw frame.
(3:03)
6. What is roller setting? Discuss the factor considered for
roller setting. (2:03)
7. Write down the basis of roller setting in Draw frame. (3:04)
8. The mechanical draft of a draw frame is 10 If the input sliver
wt is 60 gm/mt and the % of slippage in 2 and 1 respectively.
Find out the output sliver in gm/mt. (3:03)
9. What are the causes and remedies of irregular sliver in a
draw frame. (2:03)
10. Write down the causes of sliver irregularity. (2:01)
11. Which type of autoleveller is used in drawing frame?
Describe with mechanism. (4:01)
12. What are the causes of efficiency loss in drawing frame?
(1:01)
13. What are the causes and remedies of drafting ware. (2:02s)
14. What are the main features of a modern draw frame. Discuss
its function. (4:00) (3:02)
15. How doubling, drafts and number of passages influence on
quality of drawn sliver? (4:00)/ Explain the effect of
doubling, drafts and number of passages on the quality of
drawn sliver? (3:02s)
210
16. Make the relation between doubling and draft? (3:01) (2:04)
17. State the advantages of draw frame blending. (2:00)
18. State the advantages of draw frame blending over blow room
blending. (2:04) (3:02)
19. How auto-leveller and quality monitoring system is working
in modern draw frame. (5:00) (5:03)
20. What type of auto stop motion is used in modern draw
frame? Why auto stop motion is essential in draw frame?
(4:02)
21. What do you mean by “Drafting wave”? (2:02)
22. Point out the recent development of modern drawing frame.
(4:02)
23. Write down the effect of drawing and doubling on yarn
quality. (2:02s)
24. What are the causes and remedies of drafting wave? (2:02)
(2:02s)
25. Write the important stop motion device used in draw frame?
(2:02s)
26. What is hook fibre? How it forms? Mention and draw the
types generally formed in processing. (5:02s)
27. Why periodic variation occurs in draw sliver? How it can be
minimized? (3:02s)
28. Find out the DCP required to produce 60 gr/yd sliver from
62 gr/yd sliver if
Delivery speed: 400 m/min; No of doubling: 8; Draft constant:
310 (3:01)
29. Find out the number of carding m/c required from the
following data-
Draw frame:
No of draw frame: 10; Front roller speed: 1000 rpm
No of deliveries frame: 2; From roller dia: 2 inch
Hank of draw frame sliver: 0.15; Efficiency: 85%
Carding:
211
 Dia of doffer: 27 inches; Speed of doffer: 15 rpm
Hank of carded sliver: 0.15; Efficiency: 80% (5:00)
30. Find out the production in kg/day of draw frame from the
following data:
Delivery roller speed: 700 meter/min; Doubling: 8; Draft: 7.5
Feed sliver wt: 75 grains/yd; No of draw frame: 4
No of delivery head: 1; Efficiency: 85% (4:02s)
31. Find out the production in lb/shift of draw frame from the
following data:
Delivery roller speed: 600 meter/min; Doubling: 8; Draft: 8
Feed sliver wt: 60 grains/yd; No of draw frame: 4
No of delivery frame: 2; Efficiency: 90% (4:02s)
32. Input and output sliver grain/yd is 75 and doubling is 8. Find
out the back zone draft of a draw frame if tension draft is 1.2
and front zone draft is 4 (2:04)

Jute introduction + Emulsion

1. Light through on different types of jute yarn. (2:03)
2. Write down the importance of jute softening. (2:03)
3. Give the batch composition of the following jute yarn:
i) CBC weft ii) Hessian weft iii) Sacking weft iv) Sacking
warp (2:03)
4. What is the delivered count of the sliver under the following
condition:
Raw jute feeding rate: 27 lb/min
Emulsion flow: 32 gm/hour
Sp. Gr. Of emulsion: 0.97
Length of sliver in a roller: 450 yds
Time to from a roll: 7.2 min (4:03)
5. Write down the required characteristics of jute batching oil?
(3:04)
6. Give the function of oil, water and emulsifier. (3:03) (3:01)

212
7. What is conditioning of jute fibre? mention conditioning
time required for different grades of jute fibre. (3:03) (2:01)
8. Write down the procedure for preparation of Emulsion.
(2:01) (3:03)
9. How can you difference between lead and draft? (1:03)
10. Define: Lead and Draft. 92:00)
11. Give the recipe of stainless emulsion. (1:03)
12. Give an emulsion recipe for C.B.C? (1:04)
13. Compare the OD batch mixer with paddle mixer in preparing
emulsion. (3:00) (3:02)
14. How oil content affects on strength of jute yarn? (2:00)
15. Discuss the defects and remedies of emulsion. How will you
solve the defects? (4:00)
16. What do you mean by jute fibre ‘entity’? (1:00) (1:02)
17. What are the defects found in jute batching(jute emulsion)?
Mention their causes with remedies. (5:02s)
18. Draw a neat sketch of good spreader machine. (5:00) (5:02s)
19. A spreader m/c running with following particulars
Feed sheet = 6 yd/min, Feed rollers = 7.3 yd/min
Slow chain = 99.8 yd/min, calculate lead of feed roller, draft of
the slow chain and fast chain zone. (3:00)
20. Show the flow process of Hessian yarn. (3:01) (3:04)
21. Write down the importance of batching. (3:01) (3:04)
22. How many type of batch mixer generally used for jute fibre
processing? Among them which one is best and why? (4:01)
(4:04)
23. What is batch and batching? State the factors considered for
jute batch selection. (3:02s)
24. What is the conditioning of oil, water and emulsifier? (2:01)
25. If 20% emulsion is applied on raw jute of which 15% is
absorbed. Find out the amount of ingredient required to
process 12 tones of raw jute if; Oil-20%, water- 75%,
emulsifier-2% (3:01)
213
 26. What are the softening machine, used in jute processing.
Describe the working principle of any of them. (4:01)
27. How can you test the stability of an emulsion? (2:01)
28. Describe in detail jute fibre grading. (4:02)
29. Give emulsion application% for different type of jute fibre.
(2:02)
30. Give a process sequence for jute yarn manufacturing. (2:02s)
31. What is the delivered count of the sliver under the following
condition:
Raw jute feeding rate: 27 lb/min
Emulsion flow: 32 gal/hr
Sp. Gravity of emulsion: 0.97
Length of sliver in a roll(yd): 450
Time to form a roll: 7.2 min (3:02)
32. Draw the diagram of spreader m/c and discuss its working
principle. (3:02s)
33. How feed regulatory is achieve in jute spreader m/c. (2:02s)
34. An emulsion is made up of 30 lb oil and 80 lb of water and it
is to be added at a rate of 20% to the jute. How much oil will
be added to the jute. (2:02s)
35. Write down the function of Urea. (2:04)
36. Discuss the causes and remedies of defects commonly found
in raw jute? (6:04)
37. Write down the flow chart of manufacturing sacking yarn.
(2:04)
38. Differentiate between woolen yarn & worsted yarn. (2:04)

Jute Carding
1. What do you mean by up-striking, down-striking, half
circular and full-circular card? (4:03)
2. Discuss and draw the cross sectional diagram of finisher card
machine with specification. (6:03)

214
3. What is basic difference between cotton and jute carding?
(2:00)
4. What are the objects of jute carding? (2:03)
5. Discuss about the energy applied for raw jute carding at
breaker card. (2:03)
6. Describe the working principle of Breaker card with its
diagram. (5:03)
7. Show the main specifications of finisher card with its
diagram. (4:01)
8. What are different types card m/c diagram used in jute.
(1:03)
9. Give the classification of jute card. (3:02) (2:03)
10. What is shell setting? What are the effects on fibre properties
with its closer and wider setting. (3:02s) (2:02) (2:03)
11. Write down the factors responsible for effectiveness of jute
carding. (2:03)
12. Discuss the factors influence on carding action. (4:01)
13. Illustrate the finisher card m/c with its different settings.
(5:03) (4:02s)
14. Discuss the working principle of finisher card with its
diagram and mention speed pin angle and settings. (5:02)
(5:04)
15. Why two types of carding machines are used instead of one?
(2:02s) (4:00) + Operational difference. (4:02)
16. Differentiate breaker card with finisher card. (4:01)
17. Draw a cross-sectional diagram of breaker card m/c and
mention speed, pin angle & setting. (5:04)
18. Write down the flow chart of manufacturing sacking yarn.
(2:04)
19. Classify jute cards in details. (5:04)
20. How can you calculate pin density? (2:00)

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 21. A breaker card is set to work with a clock length of 12.9 yds
and draft of 12, dollop weight 30 lbs. what will be the weight
of delivered sliver in lbs/100 yds? (4:00)
22. A breaker card is set to work with a breaker card length of
12.9 yds and draft of 10, dollop weight 32 lbs. What will be
the weight of delivered sliver in lbs/100 yds? Finisher card
draft – 15, Finisher card doubling - 12 (3:04))
23. Draw the flow chart of woolen yarn production. (4:00)
(3:02)
24. Differentiate worsted yarn and woolen yarn. (3;00) (2:01)
(3:02) (2:04)
25. Write a short notes on Jute pilling. (3:00)
26. Distinguish between cotton carding and jute carding. (2:01)
27. Write down the object of jute carding. (2:01)
28. How will you control the waste in carding? (3:01)
29. Find out the production of breaker card/day if-
Delivery speed- 200 ft/min
Dollop wt- 30 lbs
Clock length- 11.5 yds
Draft- 12
Efficiency- 80% (3:01)
30. Find out the production of breaker card/day if-
Delivery speed-18 ft/min
Dollop wt- 25 lbs
Clock length- 12.9 yds
Waste- 4%
Efficiency- 80% (4:02)
31. Find out the production of breaker card/day if-
Delivery speed- 200 ft/min
Dollop wt- 30 lbs
Clock length- 11.5 yds
Waste-4%
Efficiency- 80% (4:02s)
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32. Define dollop wt. and clock length. (2;02) (2;04)
33. Describe the modern trends and developments of jute
carding. (4:02)
34. Calculate the weight in lbs/100 yds sliver from finisher card
with the help of following particulars:
Breaker card dollop wt.- 32 lbs
Breaker card clock length- 12.9 yds
Breaker card draft- 10
Finisher card doubling- 12
Finisher card draft- 15 (3:04)
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