Textile internship program report

E.G i
Bahir Dar University
Institute of Technology for Textile,
Garment and Fashion Design
Internship Program at
Ayka Addis Textile and Investment Group
By Enquzer Getachew
Duration- 20-Oct-2010 – 7-Feb-2011
Submission Date- 21-Feb-2011

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Institute of Technology for Textile, Garment
and Fashion Design
Internship Program at
Ayka Addis Textile and Investment Group
By
Enquzer Getachew
Copyright © 2012 by Enquzer Getachew
DEPARTMENT OF TEXTILE ENGINEERING
Institute of Technology for Textile, Garment and Fashion Design
Bahir Dar
Ethiopia

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PREFACE
At the outset, this paper is written during Internship Program at Ayka Textile and Investment Group
arranged by Bahir Dar University, Institute of Technology for Textile Engineering, Garment and Fashion
Design.
The material has been prepared mainly as a Report but anybody who wants to have a general view of
textile machineries and there working principle can benefit from it; with this in mind, most of the information
given is compiled form four years of Textile education and several resources gathered form the company. It is
tried to cover Spinning, Knitting and Dyeing Departments in Ayka. Hopefully the reader would find the
material useful.
It is tried to convey as much information as possible. Since production data are tentative some
information might change over time, hence it should be noted that all the information given are gathered with in
the time frame of four months.
Enquzer Getachew
Textile Engineering Department
Institute of Technology for Textile, Garment and Fashion Design
Bahir Dar
Ethiopia.
20-Oct-2010 – 7-Feb-2011

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Table of Contents
PREFACE..........................................................................................................................................................................3
A) SPINNING
1 Row Material
1.1 Introduction ............................................................................................................................................8
1.2 Problems Observed...............................................................................................................................10
1.3 Recommendations.....................................................................................................................................10
2. Textile Testing and Quality Control
2.1 Introduction to Testing..........................................................................................................................11
2.1.1 Objectives of Testing.............................................................................................................11
2.1.2 Some of the most important properties to measure .........................................................12
2.2 Lab equipments.....................................................................................................................................14
2.2.1 HVI 900 (High volume instrument)....................................................................................14
2.2.2 USTER® TENSOJET 4 ......................................................................................................15
2.2.3 USTER® AFIS PRO (Advanced Fibre Information System)........................................17
2.2.4 Uster 4......................................................................................................................................17
2.3 Colour Calibration (Uster® colorimeter 750).......................................................................................18
2.4 Quality Monitoring...............................................................................................................................19
2.5 Problems and Recommendations in lab ...............................................................................................20
3. Blow Room
3.1 Introduction ..........................................................................................................................................21
3.2 Blow room machines in Ayka................................................................................................................22
3.2.1 ROBOT or UNIFLOCK ( Reiter model A10 Herman machine)..................................22
3.2.2 CAGE CONDENSOR (Reiter model)..............................................................................23
3.2.3 Uniclean (Reiter model B11) ................................................................................................23
3.2.4 Blending feeder (Reiter model B34)....................................................................................24
3.2.5 Auto-mixer (Reiter model B )................................................................................................25
3.2.6 Horizontal opener (UNIFLEX MACHINE, Reiter model B60) ............................................26
3.2.7 UNIBLEND MACHINE( REITER MODEL B78)........................................................27
3.3Problems observed in Blow ROOM.......................................................................................................29
3.4 Recommendations.....................................................................................................................................29
4. Card (Tarak)
4.1 Introduction...............................................................................................................................................32
4.2 Operating Principle................................................................................................................................34
4.3 Problems Observed...............................................................................................................................36

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4.4 Recommendations....................................................................................................................................36
5. Draw Frame (Jer)
5.1 Introduction..........................................................................................................................................37
5.2 Parts of Draw Frame..............................................................................................................................38
5.3 Operating Principle................................................................................................................................40
5.4 Problems Observed and Recommendations.........................................................................................42
6. Unilap and Comber (penye)
6.A. Unilap
6. A.1. Introduction.............................................................................................................................43
6. A.2. Operating Principle....................................................................................................................43
6. A.3 The two types of Unilap machines .............................................................................................44
6.B Comber
6. B.1) Introduction..............................................................................................................................46
6. B.2. Operating Principle ...................................................................................................................47
6. B.3. Combing cycle...........................................................................................................................48
6. B.4. Formation of Sliver....................................................................................................................50
7. Roving Frame
7.1 Introduction.........................................................................................................................................51
7.2 Operating Regions ...............................................................................................................................51
7.2.1 Creel.............................................................................................................................................51
7.2.2) Drafting Region........................................................................................................................52
7.3.3 Spindle and flyer ........................................................................................................................53
7.3.5 Pneumatic suction: ....................................................................................................................54
7.3.6 Cone drive transmission ...........................................................................................................55
7.4 Operation Sequence.............................................................................................................................55
7.5 Problems and Recommendations ........................................................................................................56
8. Ring Frame
8.1 Introduction.....................................................................................................................................57
8.2 Principle of operation...............................................................................................................................57
8.2.1Drafting..............................................................................................................................................58
8.2.2 Ring and Traveller...........................................................................................................................58
8.3 Twist............................................................................................................................................................60
8.4 Recommendations ................................................................................................................................61
9. Winding
9.1 Introduction ..........................................................................................................................................63

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9.2 Operating Regions.....................................................................................................................................65
9.2.1 Drum winding ...............................................................................................................................65
9.2.2 Splicing............................................................................................................................................65
9.2.3 Yarn Waxing ..................................................................................................................................66
9.2.5 Yarn Clearing.................................................................................................................................66
9.2.4 Compensation type (Gate type) tensioning device ..................................................................67
9.3 Steaming (Walker APS 7 machine)........................................................................................................67
9.4 Recommendations ................................................................................................................................68
10. Rotor
10.1 Introduction ........................................................................................................................................69
10.2 Basic Principle of Open-End Spinning .................................................................................................69
10.3 Working principle................................................................................................................................71
10.4 Problem and Recommendation...........................................................................................................74
B. KNITTING
2.1 Introduction ...........................................................................................................................................77
2.2 Basic Structure Circular Knitting Machine............................................................................................78
2.2.1 The Yarn Holding System......................................................................................................78
2.2.2 Yarn Feeders ............................................................................................................................79
2.3 Stitch Formation Motions........................................................................................................................80
2.4 Take-down and Winding Motions..........................................................................................................83
2.5 Quality control.......................................................................................................................................84
2.6 Problem Observed and Recommendation...............................................................................................90
C. DYEIING
1.1 Introduction ...................................................................................................................................93
1.2 Dyeing Procedures..........................................................................................................................95
2 Mechanical finishes................................................................................................................................98
2.1 Compacting and Shrinkproofing...............................................................................................98
2.2 Sanforization ..............................................................................................................................98
2.3 Raising .......................................................................................................................................... 92
3 Printing .......................................................................................................................................................93
4 Analysis of Water ......................................................................................................................................95
Conclusion......................................................................................................................................................................96
Refrences.........................................................................................................................................................................97
Appendix.........................................................................................................................................................................98

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A) SPINNING
The term spinning means to ―rotate‖. A set of fibres arranged in a continuous strand is rotated to form yarn
at he last stage of yarn formation and thus the term spinning. The objective of spinning is to produce a yarn. If
the single yarn is untwisted they will disintegrate into fibres. Two or more single yarns may further be combined
into a single strand and twisted together to make doubled/ twisted yarn.
In short staple spinning process, fibres having a staple length of about 20 to 40mm are converted to yarns. Or
broadly fibre shaving characteristics similar to cotton, particularly with regard to length are converted to yarn.
Blow room- fibres arrive in the spinning factory in the form of bales of fibres which are highly compressed
and there is no particular order in the arrangement of fibres in the bales. The bales of fibres contain non fibrous
material (trash). The major function of blow room is to clean the feed material and open the material so that the
next machine can take over.
Card- The material form blow room is fed to the card. The feed material for card can be either in a lap form
or through ducts pneumatic transport. The function of card is to individualize, further clean and arrange the
fibres in a more or less parallel form and deposit it in a sliver can.
Draw Frame- card sliver is passed to the first passage (Breaker draw frame) of draw frame where 6 to 8
slivers are red to a single drafting system and are drown together. Again the out put of the first path is fed to
another path (Finisher draw frame) set 6 to 8 slivers to double or to even out the variations present in card
sliver so that the out put will be more uniform, hooks hat are formed in card are removed and to improve
evenness of the output.
Comber- is an optional process which is used when a high quality product is demanded. Short fibres are
removed and other defects are improved. The feed material for comber needs to be prepared with comber
preparatory machines like Unilap machines which are called Comber lap. Combing process removes a
significant amount of waste which is called Comber Noil. The output of comber machine is called Comber
Sliver.
Roving Frame- finisher draw frame sliver is drafted to the required thickness which can be handled
efficiently by the next process. A protective twist is added to the material and wound into a package. The out
put is called roving. The drafting system is done by ―top arm‖ drafting system and twisting operation is carried
out by spindles and flyers.
Ring Frame- The roving is drafted, twisted and wound into a package. The drafting system again carried out
by Top arm drafting system and twisting is done by spindle and traveller. The package is called Ring Bobbin
or Ring Cop. Apart form Ring frame Spinning can be carried out by Rotor Spinning machine.
Cone Winding- the yarn from ring spinning machine is in the form of small packages containing short length
of yarns. These small packages are fed to a winding machine in order to get larger packages. The output is
conical package called Yarn Cone. During winding quality improvement is possible by clearing yarn defects
while winding.

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1. Raw material
1.1 Introduction
In yarn production, row material forms a quite substantial part of the cost of production. Row material
quality, in a figurative sense, is responsible for about 90% of the yarn quality - in other words, whatever else is
done, without proper raw material quality, obtaining satisfactory yarn quality is almost impossible. Thus
ensuring good raw material quality assumes a very high level of importance ensuring at the same time the costs
are maintained at the lowest possible levels. Raw material influences productivity & quality to a very large extent.
Ayka textile factory purchases its row materials from different ginning factories both from domestic and
foreign ginning companies.
Organic cotton from Turkey provided by Mustafa cotton ginning company
Inorganic cotton from local markets like – upper Awash/Omo valley- Amibara ginning factory
Arbaminch ginning fatory
Cotton from Mohammed Amiru
Cotton from Endirs in Awash
Middle Awash –Sami ginning factory, Lucy ginning factory
Cotton from Bukina faso
Cotton from Nazilli in Turky
Manufactured row materials like viscose and Pollster form India
Dyed cotton from dyeing department
Here there is a significant difference between organic and inorganic cotton. In addition to Organic cotton,
as the name implies is grown naturally with no synthetic fertilizers applied like using manure. While Inorganic
cotton is grown using man made fertilizers like urea and ammonium nitrate.
Organic implies both the nature of growing and the process. In addition to naturally growing cotton, it
includes natural way of production. This means natural place to wok for the workers. Textile companies tend to
be loud inside with huge machineries with there rolling parts and also exposure to dust and fly. Natural way of
work means all workers are provided with the necessary protection against dust and other breathable health
hazards like cotton fly. In addition, it requires the sound level they are exposed to be carefully calibrated so that

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there is opposite correspondence with there working hour or are provided with proper insulation. Workers wok
the natural duration of time which is globally accepted hours i.e. 8hrs
Inorganic way of production which Ayka is following excludes most of the organic provisions. Not only
there is no limit for sound levels which the workers are exposed to, working hour is extended to 12Hrs.
This difference in way of production has effect in cost of cotton in that organic cotton is at least 15%
more expensive than the inorganic one.
Row material is purchased in a form of bale form different places so the quality and quantity differs form
one bale to another. So there must be a way to identify them. There is a paper with list of identifying queries on
each bale to do that. The includes
1) Batch no-which identifies the pat of farm the cotton is harvested from
2) Bale no- no given in sequence for each bale
3) Lot no- an identification number for that bale. Ayka give different lot no depending on from what
country the bale came. For example bale form any part of Ethiopia has the title ―et‖ fallowed by a
number, for polyester M-33/P2006.
4) Gross weight – weight of the bale with the packaging material
5) Net weight - weight of bale without packaging material
6) Colour- colour value of row material
7) Quality- two set of numbers each designating diameter and staple length consecutively.
E.g. 1.2*38
8) 8 Year- time where the bale is pressed
The net weights of bales vary form 180 to 250kgs per bale. For example Ayka imports white cotton with weight
ranging from 205 to 215kgs. Synthetic products ranging form 202 to 220 kgs.
Bales are stored in storage room with no proper temperature and humidity. And are transported form store
room to spinning department using forklift.
Whenever there is requirement of row material form store room there is a list to be filled which include in
which the amount is determined by stock manager. Spinning department has its own store room so row material
can be moved when ever it is needed.

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1.2 Problems Observed
1. There is no systematic arrangement of bales and poor space utilization Fig 1.1 A. The bales at the
bottom get pressed highly which causes high inter fibre friction. This leads to uneven bale opening. It
also causes high temperature build up around the bales.
2. Putting waste with clean row material Fig 1.1 B. This causes contamination of the clean cotton bales
since cotton bales must be stored open to the environment for accumulitization (a process of natural
adjustment of fibres with the environment) of the bales to the temperature and humidity the room.
1.3 Recommendations
Having proper material storage is a key point in to minimize processing difficulties and also to produce quality material.
Row material has a significant share in cost of production; hence it should be stored properly.
There are many ways for storing bales, the 5s system is the most suitable one. 5s system a monogram to arrangement
based on sorting (eliminating unnecessary equipments), Setting in order, Sweeping cleanness of the room, Standardizing
(identical or consistent or symmetrical arrangement), Safety (the basic thing for both operators and row material). Based
on this and the most likely quantity need of the factory, easy access and easy loading and unloading, reusable waste is
placed closer to the door and is covered partially with a plastic to avoid contamination by dust, and man made fibers are
stored closer to it since they are stored covered, is the following top view of store room is recommended. The air
condition system is recommended on Draw frame problems since its effect can be mainly seen there.
Fig 1.1 Problems in method of Storage
A B
Cotton bales
Man made fiber bales
Trash containing bales
Movement path for operators
Door
Plastic cover
Store room wall

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2. Textile Testing and Quality Control
2.1 Introduction to Testing
 Testing can be a valuable aid to those engaged in production, distribution and consumption.
 Testing instruments can not make decisions! A human being has to study, analyse, interpret and device
means of using the test results to the maximum extent possible.
 Just because a material has been tested does not enhance the technical quality of the (tested) material!
(Most of the tests are destructive; some tests though not destructive, may deteriorate the quality!)
 The person in charge of a textile mill laboratory should be a ―first-class‖ textile technologist. Further, he
should be a part-scientist, part-statistician, part-technologist and part-diplomat – all these combined in
one person!
 The variety of textile testing instruments is quite large. They range from very simple to quite complex;
employ a wide range of principles; cost almost nothing to hugely expensive.
2.1.1 Objectives of Testing
Selection of raw materials
All the natural fibres have properties that vary very widely. Similarly, yarns (raw materials for weaving) and
fabrics (raw materials for wet processing and finishing and garment factories) also have wide range of
properties, which too vary quite widely. Selection of raw materials is an important technological function; this
invariably requires testing. In the case of man-made fibres, testing of properties is usually not done at the level
of textile mill, as they are tailor-made; however, occasionally, even the man-made fibres need to be tested.
Process Control
When the process (i.e., manufacturing process) goes out of control, the costs go up, the number of defectives
rise; the wastes go up and so on. To prevent the process going out of control, the output at each stage has to
be tested for relevant properties. When the properties are within the stipulated limits, the process is said to be
within control.
For effective process control, quick results are required - so that production of defective material is stopped as
quickly as possible. Thus, testing laboratory should be as close as possible to the production departments.
Process Development
Many a time, it becomes necessary to carry out tremendous experimental work to arrive at optimum
levels of processing parameters (to give an example). The materials need to be tested at each stage to arrive at
valid conclusions.
Product Testing
When the raw material is properly selected and when the process is controlled tightly, the product is
bound to be with the necessary quality. Unfortunately, this is never completely true! It is quite likely that all
known parameters are quite within stipulated limits and still the quality is not satisfactory. If thus becomes

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necessary to test the final product – to find out whether ‗everything‘ is quite alright, the performance of goods in
actual usage also needs a variety of tests.
In spinning, quality can be achieved only when the following are ensured (apart from the management aspects):
Adequate quality of raw material for the given type and count of yarn
An excellent degree of machine maintenance
Availability of machines which are well-designed and maintainable with reasonable degree of reliance. Poorly
designed machines invariably means poor quality and they are not unknown in the textile field
Correct/optimum choice of machine settings, speeds and process parameters
Quality control schedules (like the frequency of studyes, the scheme of sampling etc) should be drawn
according to the needs of the company
Resources for quality control activities in terms of personnel, equipment, support from the top management,
proper environment for dissemination of information and corrective action without hostility are essential
An adequate system of documentation should be maintained so that information is recorded and maintained
properly for any future reference.
There is a relationship between fibre properties and yarn properties. For this reason the testing of raw fibre
properties is important to the cotton spinning mill to predetermine yarn strength and spinning production
2.1.2 Some of the most important properties to measure
Length
Generally, when a physical characteristic is of interest, the measurement is made and, usually, the
arithmetic mean is calculated. Most likely, in many cases, the standard deviation and the co-efficient variation
are also calculated in order to assess the variation. Sometimes, a histogram is also constructed to observe
visually the distribution in a graphical form.
Interpretation of fineness results obtained by air-flow methods of cotton fibres
Immature and half-mature fibres have lower mass per unit length than mature fibres because of the lower
mass of cellulose contained in the secondary wall; although the thickness of the fibre may be the same. Thus, a
given sample of cotton fibres with a higher level of immaturity will contain more number of fibres for a given
mass than mature fibres. Obviously, the sample with higher level of immaturity would show ‗fine‘ reading
than is actual.
The perimeter of cotton varieties is a genetic factor - i.e. the transverse dimension is an inherited
characteristic which is not affected by growth conditions. However, the growth of secondary wall (in other
words, the maturity) is highly influenced by growth conditions.
A finer reading for a given variety (than is normal for that variety) indicates poor maturity. Thus, micronaire
value is an indicator of maturity under this set of conditions (rather than the fineness in terms of

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micrograms per inch)! Thus, results based on air-flow methods should be carefully considered along with
the maturity of fibres arrived at by other methods.
Neps and Seed Coat Neps
Fibre Neps
The amount of neps in raw cotton depends on the cotton variety or origin and harvesting method. Fibre
neps are generally defined as entanglements of several fibres. Mechanical treatment of the cotton fibres during
harvesting, ginning and opening and cleaning of the fibres in the spinning plant generate them. Neps are
reduced at carding and combing. The amount of reduction highly depends on the machine performance, the
production level and the overall quality that the spinning mill wants to achieve.
Neps do not ―grow‖ on the plant. Seed cotton does not contain any neps. However, as soon as the fibres are
picked – and especially when they are picked mechanically – neps are introduced to the fibres. The amount of
neps further increases in ginning and in opening and cleaning of the spinning mill. The main reduction takes
place during carding and combing. Whereas the amount of neps increases in opening and cleaning, the amount
of trash is reduced. After all, this is the task of the cleaning equipment: Removing the remaining trash particles
and opening the cotton for further spinning preparation.
The cleaning process works best with the cotton being opened. The cotton is transported from one cleaning
stage to the next in the ductwork via air. This process can cause the increase in nep content. The more open the
fibres are toward the transporting air circulation, the more the fibres tend to form neps. Machine manufacturers
have a good understanding of this behavior and will design the opening.
Seed Coat Neps
Seed coat neps are fragments of the cottonseed that still have some fibres attached. They are created mainly in
ginning when the fibres are being separated from the seed. The amount of seed coat neps in raw cotton depends
on the quality and the aggressiveness of the ginning process. The number of seed coat neps can slightly increase
in opening and cleaning. They are mainly reduced at carding. However, the removal of seed coat neps is very
difficult since the attached fibres tend to stick with the fibres in the process.

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2.2 Lab equipments
2.2.1 HVI 900 (High volume instrument)
The speed of the HVI (+High Volume Fibre Test System) instrument allows every bale of cotton to be
tested. The challenge then becomes how to effectively use the information to improve the spinning process. All
cotton has a natural variation of fibre properties. Some of these variations are small but others may be quite
large. This variation is greatest between bales of cotton grown with different seed varieties. We also find variation
of fibre properties within a cotton seed variety. Many factors influence the variation of fibre properties. These
include growth area, climate, planting and harvesting practices. A typical distribution of the length variation of
cotton with a 27-mm staple length is shown below. These types of normal distributions apply to almost all of the
fibre properties measured by the HVI instrument.
HVI Applications
The HVI can be used in a variety of applications in the cotton industry. Some of these applications are
listed below.
Instrument for Measuring Length, Uniformity, Strength, Elongation, Micronaire, Color, and Trash for
Cotton Fibres
Cotton Seed Breeders — Verify progress in attaining goals in development of new varieties of cotton.
Cotton Producers and Government Standards -grading and Classification for use in establishing the loan
value and spot market price of cotton.
Cotton Research —Basic research and investigation of various physical properties of textile fibres.
Working Principle
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 and Color/Trash Modules.
Included with the system are an alphanumeric keyboard, a monitor and a balance. The monitor displays the
menu selections, operating instructions and test results. As tests are completed for each sample, the results
can be transmitted to a printer and/or an external computer system, if available. The HVI 900 system
consists of modules that can be combined in a variety of ways. Your system may include any or all of the
following components: the Length/Strength Module, the Micronaire Module and the Colour/Trash Module.
1 Length/Strength Module
The Length/Strength Module optically determines fibre lengths and associated uniformities. The length,
known as the ―elongation,‖ is calculated by averaging the length of distance the fibres will extend before
breaking. The Strength is determined by measuring the force that is required to break a sample of a known
mass.
The Length/Strength Module of the HVI 900 consists of a brushing mechanism, an optical system for
measuring length and uniformity, and a clamping jaw system for measuring strength and elongation. It is
operated by placing a sample prepared using the Fibro sampler 192 in the comb track of the Fibro-graph
Plus where it is automatically brushed and moved into position for testing.

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The comb track is enclosed within the Length/Strength cover. To access it, lift the door located on top of
the brusher and place the fibro comb in the track. The Length/Strength start button is then pressed to
initiate the measuring process, or it can be automatically prompted using the software.
♦ The main power and blower switches are located on the Length/Strength Module plexiglass cover.
♦ The vacuum box has been replaced with a lint/waste box and blower system. The lint/waste box is
located behind the left door of the Length/Strength Module cabinet. The blower can be turned off when
not required for measurements.
♦ Two buttons, located on both sides of the Color/Trash mechanism, must be pressed simultaneously to
initiate the Color/Trash Test.
2 Micronaire Module
Micronaire is measured by relating air flow resistance to the specific surface of fibres. An air stream is
passed through a known mass of fibre confined in a chamber of fixed volume. The pressure differential
across the chamber is then related to the specific surface of the fibre to determine the micronaire value for
cotton.
Before a sample is placed in the micronaire chamber, it must be weighed. A precision electronic balance
is provided to weigh the sample and is protected by an acrylic guard (the optional bar code reader can be
attached to it). The testing chamber for micronaire measurements is located directly below the electronic
balance
2.2.2 USTER® TENSOJET 4
Working principle
The USTER® TENSOJET 4 is a tensile testing installation for the quality control in the textile
industry. It tests the real strength of textile staple fibre yarns. The determined values for the tensile force and
elongation allows to make a prognosis on the suitability of the tested yarn with regard to the behavior in the
future processing as well as on the quality of the end product.
Figure 2.1 HVI 900

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The digital tensile testing installation USTER® TENSOJET 4 determines the breaking force and the
corresponding elongation of textile yarns. Because of the high-resolution, digital scanning of the
force/elongation characteristics during a measurement, the computer is able to determine additional test values.
In addition to this, the force/elongation characteristics can be recorded as a graphic display. The measurement
of the tensile force in the yarn is achieved indirectly by a force sensor.
Force diagram
A Test material F Normal force
B Drafting rollers FT Tensile force in the test material
C Force sensor FM Measured force
A Test-Unit casing
B Suction nozzle C Force sensor
D Disk drives
E Yarn cutter
F Key block
G Yarn changer
H Yarn clamp
I Cutting device
J Pair of transportation rollers
K Yarn storage unit
Constant rate of elongation (CRE) testers
In order to standardise the conditions of the test, it is desirable to load or extend the specimen at a
constant rate through out the test. However, though this looks simple and straightforward, there is a
complicated interaction between the extension of the specimen and the movement of the load-measuring or
load-controlling system. Some methods also give rise to inertia or other errors.
L Pair of control rollers
M Laying-in arm
N Feed-in jet
O Pair of upper drafting rollers
P Cover of the measuring channel
Q Pair of lower drafting rollers
Figure 2.3 Tensiojet parts
Figure 2.2 Tensiojet working Principle

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2.2.3 USTER® AFIS PRO (Advanced Fibre Information System)
Working Principle
Uster Afis measures fibre length and maturity in raw cotton, card mat and sliver. The length is measured on
single fibresin order to get a true fibre length distribution within a cotton sample. The AFIS PRO is
the only instrument that measures the maturity of single fibres, resulting in a true distribution of maturity within
a cotton sample.
The AFIS measures every single fibre in a cotton sample. Three-thousand fibresare counted in each sample,
resulting in a true fibre length distribution by number. The following parameters are reported on the AFIS:
Most spinning mills today use the USTER® AFIS PRO to control the opening and cleaning line, the cards and
combers in their plants on a regular basis. Draw frame slivers are tested less regularly, and roving only in cases
where a change in the machine settings requires it. However, there is generally no direct influence on the fibre
material possible after combing in the spinning process. For regular quality control purposes, it is sufficient to
test material until comber sliver, only.
Fibre Fineness [mtex] is determined optically on the AFIS PRO by analyzing the fibre shape passing
the sensors. Originally, fibre fineness [mtex] is determined gravimetrically by cutting and weighing the sample
[3]. An algorithm determines fibre fineness based on the shape and form of the fibres. As mentioned before,
mature fibresdo contain more cellulose than immature fibres. Thus, mature fibresare also heavier fibresthan
immature fibres. This results in a higher fineness value for mature fibre since mtex. Fibresthat are less mature,
containing less cellulose, therefore result in a lower fineness value.
The purpose of opening and cleaning in the spinning mill is, as the name says, opening the cotton and
cleaning the trash out. Further cleaning can be achieved at the cards. Most modern machinery today also
includes suction systems to reduce the dust emission in downstream processes, for example at the draw frames.
Ayka uses the USTER® AFIS PRO to control the opening and cleaning line, the cards and combers in their
plants on a regular basis. Draw frame slivers are tested less regularly, and roving only in cases where a change in
the machine settings requires it. However, there is generally no direct influence on the fibre material possible
after combing in the spinning process. For regular quality control purposes, it is sufficient to test material until
comber sliver.
2.2.4 Uster 4
Working Principle
The digital USTER® TESTER 4 installation with its capacitive sensor determines the mass variation in
rovings and slivers, staple fibre yarns and filament yarns. Optional optical sensors allow the measurement of
evenness, hairiness, surface structure and impurities in staple fibre yarns. Additional systems for gravimetric
determination of material count can also be connected to the installation.
With the combination of the TEST-UNIT and the integrated computer in the CONTROLUNIT, the system is
capable of providing detailed information on the tested material and presents the test results in numerical and
graphical form.

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The USTER 4 displays results a combination of graphics which represents test values and a simultaneous
colour-coded classification and assessment of the quality data, which are extremely easy to read and
interpret.Most of the time Ayka lab uses this machine to measure CV% variation.
Using Uster 4 uses two types of sensors:-
 SENSOR CS
Function: Measuring unit for the determination of mass variations in yarns, rovings and slivers of staple fibres
• Measurement range: Approx. 1 Tex to 12 ktex
• Measurement technology: capacitive measuring unit
 SENSOR OH
• Function: Measuring unit for the determination of the
hairiness of staple fibre yarns (simultaneous with the
determination of mass variation)
• Measurement range: Approx. 5 tex to 1000 but tex
limitations according to the type of fibre are possible
• Measurement technology: optical measuring unit
2.3 Colour Calibration (Uster® colorimeter 750)
Color identification is one of the necessary requirements to identify the quality of a raw material and for
materials in blow room. The standard reflective index (Rd) and brightness (+b) values are fixed using a Ceramic
tile which has two sides of brown and white (Fig 2.5 B) as a standard. The tiles are observed in the order
requested on the machine. We first calibrate the White tile and then the Brown one. During this procedure, the
tile being measured is compared to the standard value stored for that tile in the memory unit of the colorimeter
machine (Fig 2.5 A). If the values are different, the system adjusts the constants. This could cause measurements
to be skewed is the incorrect tile is tested. The standard values are shown in the table below.
After the machine is properly calibrated ten samples are taken, for example form bales with same lot number,
(refer to raw material) then they are put on the screen found at the top of the machine so that no light penetrate
through the sample to be tasted. The values of Rb and +B appear at the control panel automatically. This value
Tile color Rb value +b
Brown 58.1 11.9
White 79.1 4.4
UT4-SE/M
1 Control unit
2 Test Unit
3 Screen, Keyboard, Mouse
4 Printer
5 Package carrier
Figure 2.4 Uster® 4 main parts
Table 2.1 Colour calibration tiles types

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is compared from a list of values. For a given colour range (21-1, 31-1, and 41-1) is termed as white colored
cotton and spotted cotton has (12-1, 31-2, and 41-2) values.
2.4 Quality Monitoring
As row material is delivered the lab performs many tests using the above lab machines. Each machine is
used to measure particular property of the sample under standard atmosphere for textile testing which is
temperature of 20±2 °C (68±4 °F) and 65±2%.
Uster Afis measurements are Finesse, Nep size and contents, maturity, dust and trash contents,
Uster HVI 900 measurements include Micronaire value (Finesse), length, strength and uniformity.
Uster Tensiojet measurements are elongation under tension and other physical properties.
Results are compared between practical measurements and the data provided in the USTER® STATISTICS
table. The USTER® STATISTICS for are established by collecting quality and productivity data online with the
data system USTER® SLIVERDATA in the spinning preparation of short-staple spinning mills. The data are
procured on a global scale via agents, international partners or direct contact with customers and are based on
the measurement results of a total of 550 deliveries of sliver producing machines collected by USTER®
SLIVERDATA customers from every part of the world. The USTER® STATISTICS for samples consists of
several parts, each addressing a specific quality or productivity aspect in the production sequence of fibres or
slivers in the short-staple spinning mill. The different sections are arranged according to the material
composition. Each section is subdivided into distinct quality or productivity characteristics (e.g. mass variation,
production per hour, etc.) which were recorded with USTER® SLIVERDATA. A measurement can consist of
several individual parameters. Mass variation, for instance, includes CV% andCV100m%. These parameters are
presented in graphic form. A register is provided for quick reference to the sections of interest.
If the results are compatible with the Uster values provided then that sample will pass. If not after some
more tests it will be rejected and necessary measures like adjustments of machine setting or change in
conditioning or any other measures are taken.
Figure 2.5 A) Uster® colorimeter 750 machine B) Standard tile

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2.5 Problems and Recommendations in lab
 The objective of maintaining standard atmosphere in the testing laboratory is to ensure that the test
specimens are conditioned to the standard atmosphere either by evaporation of excess moisture presents
within them or by absorption of moisture from the atmosphere into the specimen to the standard regain
levels. Invariably, the conditioning process takes about 24 hours – more or less – depending on the ability of
the test specimens to absorb or to desorb. Well-opened out specimens will condition quickly whereas highly
compressed specimens take inordinately long time. Cotton as a hygroscopic fibre absorbs moisture and
becomes stronger with it. The time it remains in a conditioned or unconditioned area determines how much
moisture will be retained.
 The other thing that must be improved is the mode of transport of the specimen from the corresponding
machines. As the air is full of flies and different temperatures from blow room to winding, the specimen to be
tested must be transported to the lab with in an insulated medium. The location of the lab in Ayka is in front
of the ring frame. Though temperature and moisture in the air is adjusted to the appropriate value in each
department, specimen form card from section 2, i.e. the section which produces black (dyed) and blend
products, the relative humidity is more and the temperature is less in that section, so if a card sliver is exposed
to the conditions in section one, i.e., white cotton processing department with higher temperature and
humidity, the sample will be conditioned to the first section air condition and not the true condition. So it will
result in wrong figures in testing the specimen since the testing methods in much of the lab instruments is
capacitance and optical methods. Not only the material is contaminated by section 1 flies form white product
which influence the optical measurement, the moisture content will change making it less resistive to electric
current making the instrumentation inaccurate to a significant value.
When samples are brought into the testing room, it is important to know whether the humidity in that
room from which they brought is higher or lower than that in the testing room. If the humidity in the room
from which the samples were brought is lower than that of the testing room, then even after a long
acclimatization time, the room will attain lower moisture content than if the yarn had been brought from a
room with a higher humidity. For instance for a room of 65% humid, the moisture content will approach
approximately 6.8% if the yarn is coming from a room with lower humidity and approximately 7.8% if coming
from a room with higher humidity. Here moisture content of yarns is referring to this value with respect of
the yarn mass. Therefore, with a cotton bobbin of 7000 m of yarn, with 25 tex (Nm 24), a moisture content of
6.8% is referring to the complete yarn mass on bobbin is 179gm, of which 11.9g is water.
Therefore, it is of utmost importance to operate in a controlled laboratory environment, if a laboratory wants
to obtain repeatable results.

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3. BLOW ROOM
3.1 Introduction
In the conversion of baled cotton into finished yarn, the primary purpose of the preparatory processes
is to open, clean, and parallelize the fibres and then present the material for spinning. In doing so, these
processes convert a three-dimensional bale of compressed, entangled, matted fibre mass into an orderly
arrangement of fibres in a one-dimensional continuous strand length. The objective is for the conversion to be
achieved with minimal fibre breakage and no fibre entanglement remaining in the strand length. A great deal of
attention has been paid to, among other factors, improving machine setting and the operating speeds of
component parts so as to attain gentle working of fibres and to avoid fibre breakage. In order to do that a
number of different machines are situated for conversion of the bale form to the appropriate package to be
transported to the carding machines. These machines are collectively known as blow room machines and the
place is called blow room.
Generally the functions of blow room include
I. Opening and cleaning
Dirt can be practically removed only from surfaces.
New surfaces must be created continuously in blow room for continuous cleaning to be
achieved. That is why Ayka has many machines with different setting but basically has rotating
beater that are used for creating new surface.
The ‗form‘ (the size, the gap between the beaters and so on) of opening machine must be
adapted (suitable) to the degree of opening already achieved. The opening devices must become
continuously finer; within a blow-room line, a specific machine is required at each position.
The degree of cleaning is linearly dependent upon the degree of opening.
Newly exposed surfaces should be as far as possible cleaned immediately (cleaning should
immediately proceed opening).
A high degree of opening in blow-room facilitates prevents or reduces fibre damage (reduction
in staple length) for better cleaning in carding.
II. Disentangling and further cleaning
III. Fibre straightening and parallelizing (with short fibre removal and additional cleaning)
IV. Flock Blending and Mixing.
Blending involves combining different row materials to achieve end use requirements
Automatic bale opening machines do the job much more satisfactorily (with control systems – to
extract exact quantities from each type of bale/blend/fibre). Weighing hoppers also do a satisfactory job.
Blending machines; mixers do a similar job; where blending can be controlled more satisfactory (as found in
blending machines.

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Figure 3.1 Automatic Uniflock machine
Objectives of blending
1. To give the required characteristic to the end product (e.g., MMF + Natural fibres – to give advantages
of both MMF and natural fibres)
2. Compensate variation present in one variety (of, say, cotton)
3. Reduce overall cost
4. Improve processing conditions
5. Obtain effects – by mixing different colors, other characteristics and so on.
Mixing- involves combining similar row material to produce a single property of cotton. Its main purpose is
to activate basic product uniformity that results from the combination of variability of row materials each
exhibiting different degrees of variability.
In Ayka, the blow room is divided in two sections. The first section is used to process row cotton or
man made fibres like viscose and the second section is used to process dyed cotton which comes form
dyeing department. There is a separate room within the first section to process polyester.
This division of sections is necessary to avoid contamination of each row material. Also the second section
is used for blend products like Grimilage and Antras which vary by the amount of blackness. The Grimilage is
darker and has 52% black cotton blend and Antras which is slightly lighter has 42% black cotton blend.
Though the sections are separated the same machineries work in both parts. The general air condition for
Ayka blow room is 29.2 to 32 degree centigrade and relative humidity 44.6%.
Below is explanation of each machine in the blow room.
3.2 Blow room machines in Ayka
3.2.1 ROBOT or UNIFLOCK ( Reiter model A10 Herman machine)
The initial opening of bales of virgin cotton and short-staple man-made fibresis commonly performed by
machines called automatic bale openers . Figure 3.1 depicts a typical arrangement. As shown, rotating opening
rollers fitted with toothed discs are made to traverse a line of preassembled cotton bales, the toothed discs
plucking tufts from each bale as they move from bale to bale. The arrows show the path of tufts transported by
airflow.
The robot can accommodate 160 bales at once. It is used
1. control unit
2.bale
3. working head with
toothed disks
4.swivel tower
5.air duct for material
transport

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for picking a predetermined amount of tuft from each bale. It has sensors underneath #3 to identify the
presence and height of bale remaining so that can adjust its head to the required height. The head can also rotate
manually 180 degrees so that 80 bales can be put on each side of the head.
It moves fallowing its rail #6 to pick from each bale. There is a motor underneath which moves the belt that
moves the body of the robot. The tuft moves through #3 and enters a tube which runs through the length of
the robot. The tuft moves inside the hallow rail to the argema machine. To do this the tube moves with the
belt. In other words as the robot moves the tube and the belt are in contact so that direct and continuous
transportation from head to rail takes place.
The control panel #1 controls the overall performance of the machine. It controls its speed, operation,
conversion of signals form sensors to appropriate action for the head or any other part of machine. It is also
used as an interface so that any error can be identified easily or for the orator to take action.
3.2.2 CAGE CONDENSOR (Reiter model)
To remove dust particles in transporting airflow, a perforated surface may be used to separate the tufts
from the dust-laden air. Figure 3.2 illustrates the use of a rotating perforated drum, often referred to as a
condenser drum, cage condenser, or dust cage. The airflow in which the tufts are conveyed is generated by a fan
connected by ducting to the interior of the cage. As shown, the tufts are pulled onto the outer surface of the
drum, the holes being sufficiently small to prevent fibre loss, while the dust-laden air flows through the holes of
the drum for the dust to be collected as waste. To remove the tufts attached to the slowly rotating drum, the
suction is blanked off by a half-cylinder screen, which is positioned where the tufts are required to leave the
drum. Condenser drums are positioned at the inlet to a hopper either before or after an opening stage.
It is used to transport the material by air (pneumatically) due to induced along the line of the cage condenser
by the rotation of motor fun. Its perforated drum is used for the separation of air and material. The purpose of
separation air from the material is to prevent the damage caused by high concentration of air. High
concentration of air may explode the machine if it is removed. And it is found at the top of most machines in
the blow room.
3.2.3 Uniclean (Reiter model B11)
The Uniclean single-beater system takes advantage of the small tuft size that can be produced by automatic
bale openers. The pin projections from the beater surface are smaller and greater in number, and the objective is
to make contact with all tufts. It can remove the heavy impurities of sand, dirt, and fine trash, working on small
tufts enables the removal of dust particles.
Figure 3.2 cage
condenser

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Figure 3.3 Diagram of cage condenser
1) Single beater (2) flexible pin projections and grid bars (3) trash removal paddle.
With these systems, curved plates are fitted above the beaters to
control the number of spiral passes usually a minimum of three times. The
tufts are accelerated, decelerated, and turned over during each pass. The
angle of the grid bars and the space between them can be adjusted so as to
optimize the amount of impurities removed and to minimize any removal
of fibre. The beater speed range is 400–800 rpm, with a diameter of 750
mm and a working width of 1.6 m; production rates are up to 1200 kg/h.
Importantly, trash particles present in the tufts are not crushed. This would
increase the number of fine particles, thereby reducing the effectiveness of
the system and making subsequent cleaning more difficult.
3.2.4 Blending feeder (Reiter model B34)
Blending feeder is used to obtain even blending of materials of the same quality or different qualities. The
machine can be used single in case of reduced production, or in group. Its aim is to mix clean and open the row
material.
Feeding is always by lattice. At delivery the material falls on conveyor belt, in case of group machine; the
material is pneumatically sucked, in case of single machine. In Ayka there are 4 blending feeders 2 for
processing white cotton and 2 for dyed cotton. So there is a pneumatic system of transport the material due to
induced air by the cage condensers.
Generally we can do about five points of action
1 initial manual treatment action
2 mixing action in blending box or hopper
3 tearing action with spikes of inclined and evener lattice
4 detaching action of detaching roller
5. Beating action of porcupine beater against the sharp edge of grid bars
Operation sequence of blending feederFigure 3.4 Blending feeder

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The material reaches the blending box by means of an inlet lattice with electromagnetic cutch drive.
Feeding is controlled by screen, at the blending box inlet, which signals the lack of material lightning a lamp on
control panel. In the blending box the material falls on bottom lattice, which transports the tuft towards the
incline lattice.
A stock control screen stops the feeding from the inlet lattice when the blending box has excess of
material and restarts the feeding in the opposite cases. The material is then lifted by the inlet lattice, towards the
adjustable evener lattice, which operates opposite to the inclined lattice and therefore proportions (the material
to be forward) and opens the material. Dust removal from the blending box is made by an exhaust fan
positioned in the upper part of machine and connected to the machine drive motor.
The material is detached from inclined lattice by detaching roller, it is cleaned by a grid bar, conveyed by a
couple of conveying rollers, nipped by the pressure rollers and reaches the porcupine beater, which is the
second opening point in blowing line. Cleaning is completed by an adjustable blade grid, under the porcupine
beater, and the material is then delivered to the next machine through pneumatic system.
3.2.5 Auto-mixer (Reiter model B )
Automixer has been designed to obtain even blending from cotton and chemical fibres of different
qualities. These blending/ mixings have different density in each cell with decreasing value from the first to the
last coil.
The machine has a frame with steel coverings as required by the safety regulations. The motors and the
electrical derives are synchronized and in sequence with the centralized control panel. The main components of
the machine are the feeding unit and the delivery unit.
Feeding unit
1) Horizontal cage condenser with detaching roller
2) Upper lattice for the progressive feeding of the cells (which lattice deriving rollers (#3 and lattice
supporting rollers #4)
3) Blending cells (6-8-10) with a capacity of 50-100kgs each, according to the type and density of material.
4) one photocell with only one fed blend
5) Upper photocell to stop the feeding when the material reaches the maximum level in the last cell
6) Lower photocell to signal the minimum level of the material in the last cell
i. A2 Photocell with feeding a double blend
7) 6A upper photocell is used to stop feeding the material reaches maximum level in last cell
8) delivery unit
9) two conveying rollers per cell
10) one opening roller per cell
11) lower lattice to convey the material outside
12) safety photocell at the delivery, it stops in case of material clogging on the lower lattice
13) collecting box for waste
The operation of Automixer is divided into two phases: the initial feeding and the operation cycle.
A. First phase: initial feeding

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The discharge components of the machine are still, the feeding ones get started. The material is sucked by
the cage condenser and the upper lattices starts to progressively fill the cells. During this operation, some
material is still let into the cells already filled and therefore it determines in each cell different densities with a
decreasing value from the first cell to the last one. The cell filling is completed when the material in the last cell
or last but one if we work with double blend, reaches the maximum level mark. The whole operation is
controlled by the control panel.
Second phase: operation cycle
At this point the discharge components get stated. Under the action of the conveying rollers and opening
rollers, the material contented in the cells gradually deposits on the lower lattice and is conveyed outside
The operation starts the feeding of the machines after the Automixer acting on the drives of the centralized
control panel. In this initial discharge phase the material in the last cell goes under maximum level mark. The
photocell calls and varies the feeding without cycle of feeding and discharges with balanced compensation
between discharged material and material fed in each cell.
All theses operations are synchronized and in sequence with the centralized control panel. If for any reason
the material discharge is more than the feeding, the material in the last cell goes under the minimum level mark.
The lower photocell signals to the control panel to signal the operator that the automioxer is under the limits.
3.2.6 Horizontal opener (UNIFLEX MACHINE, Reiter model B60)
Horizontal opener is another machine for further opening of tuft with single beating roller. Its beater is
covered with metallic sow toothed neddles and it rotates eith a speed upto 450rpm. Waste material removal is
assisted with grids situated beneath the rotating roller. As the roller rotates it holds long fibre on its wires while
short fibresand any heavey material is removed throu the gaps in the grids. Also due to the beating action of the
rotating roller with the grid bars heavy material is removed while centrifugal force assists the adhesion of fibrs
to the wall of the roller. And due to suction mehcanism at he top of the machine the fibresare sucked and
removed from the roller and be ready to be transported penumatically. There is another suction mehcanism to
clear the waste form the grid and roller to be transported to waste room.
The feed screen has two photosensors positiond at the top and bottom of the transparent screen. The top
sensor detecs the maximum amount of tuft. There is an light emitter and light sensetive screen positioned parrel
Figure 3.5 Auto mixer

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to it. As there is a material in between the emitter and reciver the light form imitter cant reach the reciver. So by
relaing this information to the control pannel feeding to the machine automatically stopes until the material in
the screen is processed by closing a valve positioned at the top of the machine where feed matrial inters. The
bottom phtosensor works in the same way as the top but hre it sences lack of material so it sends message to
open the valve.
The transparent screen is adjustabel so that the volume of material accomodated insied it can be adjusted.
3.2.7 UNIBLEND MACHINE( REITER MODEL B78)
This is a basic machine for blending and mixing process. Its most important feature is that it can control
blending with the predetermined amount fed to its control system. It can process both cotton-cotton blends
and Cotton-polyester blends. As stated in the above pages Grimilage and Antras products are produced by
adjusting the amount of white cotton with the black one. Grimilage is 75:25 black white ratios while Antras is
60:40 blends. Uniblend has colour detecting sensors which work with the two valves used to insert material to
the machine. It has a microprocessor which analyzes this data and controls the ratio.
In addition to the above machineries there are also valves, which control the direction of material flow so
that it can move to the required machine, bypass valves which are used to direct material so that there will not
be any collision and it just pass through, fire sensors and automatic extinguishers, fans as a source pressurized
air for the pneumatic system of transport, an underground suction system which runs all over the spinning
department for suction of flies. There is also heavy metal separator (HMS) which separates metallic materials
form the textile material using magnet. This, if not removed would cause fire hazards due to friction and it
might also damage sensitive parts of a machine like gear teeth. So it is necessary to remove it as early as possible.
There are different duct works to transport different kind of materials and they can be identified by there
colour. This are yellow pipes for clean material transport, Blue pipes for waste transport and Red/Orange pipes
are connected to the fire extinguisher when ever there is a risk of flame in the pipes. Comber waste is recycled
and is combined to dyed cotton to make blended yarn. Blow room waste is repressed again in waste processing room and
sold to local markets for making mattes. Ring, Roving and winding wastes are also sold. The cost of wastes can reach up
to 50 birr per killo.
Figure 3.5 Horizontal Opener with location of sensors left

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Legend
Uniflock Uniclean
Uniflex HMS
Uniblend valve
Card By pass
Automixer Fan
Blending Feeder
Blending Feeder
Blending Feeder
Table 3.6 Block Diagram of Blow room

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3.3Problems observed in Blow ROOM
1) There is a considerable amount of downtime of blow room machines, i.e. most of the machines are not
working, thus decreasing the productivity of the room. In most cases the reason has been the wrong
synchronization of productivity of the machines with the next machines in the flow of materials. The
productivity of the blow room is mostly higher than the subsequent machines causing interruption of material
flow. This causes unnecessary storage of bales in blow room. This has a devastating effect in the quality of final
product. The bale is exposed to the high humidity and temperature of the blow room and due to the
hygroscopic nature of cotton, moisture is abnormally accumulated and causes inaccurate reading in lab testing
(refer to lab) and roller slippage during drafting.
2) There is unnecessary storage of unusable bales at the corners of the room. This not only occupies space it
also causes additional flies i.e., short breathable fibresin the air, and dust in the room, it adds up to the ambient
heat of the room.
3) The other problem is lack of Hygienic Aspect of Ventilation. Exposure by inhalation of dust is a major
cause of occupational illness and disease. Pneumoconiosis, which is a lung disease caused by inhalation of dust
and flies which after time will block the tiny air holes in the lung. Any excessive temperature makes it difficult
for the physiological mechanisms of thermoregulation to function effectively and, consequently, leads to a
feeling of discomfort by the workers and lowers their productivity. The workers have no protecting mask to
avoid inhalation of dust and flies and for protecting there eyes.
3.4 Recommendations
We can divide the first problem into two parts. The first is how to solve the problem stoppage of machines.
This can be solved by
1. Doing proper preventive maintenance work on time.
Blow room machines are very huge and defects might happen on any part of the machines. This
means we should have a schedule to inspect the machineries on time. This regular inspection will help
us identify problems before they cause major problem like machine stoppage and inclination of quality
of product. So using a time table which will help to regularly inspect all machines is necessary. Minor
maintenance work like cleaning, screwing, checking electrical components should be done after
inspection. A weekly Inspection and Minor Maintenance table for Blow room machines is
recommended on table 3.1.

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Mc type Monday Tuesday Wednesday Thursday Friday Saturday Sunday
Uniflock M I I I I I I
Uniblend I M I I I I I
Uniflex I I M I I I I
Uniclean I I I M I I I
Automixer I I I I M I I
Blending
feeder
I I I I I M I
HMS I I I M I I I
Valves I I I I I M I
2. Proper synchronization of Blow room productivity with subsequent machines, i.e., Card machine.
Different kinds of methods have been used to adjust the productivity of machines in Ayka. The main method
was completely stopping the machines. This measure should only be used when there is no material needed
form that machine or when ever there is major maintenance taking place. Because if the machines are stopped
when ever they are not needed, some problems with irreversible effects occur. As said before blow room
machines are huge with heavy moving parts with very small tolerance. During stoppage of machine for long
time, because of the weight of components, metallic parts start to stick together and a phenomenon called Local
welding takes place. This means because of weight and surface to surface contact the outer surfaces of metals
tend to stick together the blow room has high temperature and humidity accelerates this effect. In order to start
the machine we need more to overcome static friction costing more power, breaking sensitive parts like gear
teeth. End breakage costs more than the power intake of the machine if it worked with less efficiency.
So instead of stopping the machine every now and then it is better to use less efficiency for operation. This
method helps to give time for other machines to cope up with its production. And also the above problems are
minimized. This can be done by carefully monitoring the material stock in store room so that if a particular
stock is becoming less, we should use the above method until shortage of stock is solved.
3. The other problem is the air ventilation system which only focuses to the row material and not the
operators. It can be said that blow room is the toughest environment to adapt than any other department in
textile mill. Its high humidity and temperature makes it hard to adapt and work properly.
Ventilation and air condition is the process of treating air so as to control simultaneously its temperature,
humidity, cleanliness and distribution to meet the requirement of the conditioned space. Comfort depends
partly on humidity, and air conditioning removes moisture from the air or adds it as needed. Removing dirt and
dust from air makes the air more healthful. By controlling air movement, air conditioning brings fresh air into a
Table 3.1 Weekly Inspection and Minor Maintenance table for Blow room
machines I – Inspection M – Minor maintenance

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room and pushes out stale air. In all these ways, air conditioning provides air that makes people comfortable at
work
Any excessive temperature makes it difficult for the physiological mechanisms of thermoregulation to
function effectively and, consequently, leads to a feeling of discomfort by the workers and lowers their
productivity. Besides high temperature, many of the production processes in textile mills are accompanied by
the liberation of considerable amounts of water vapor (sizing, bleaching, dyeing, wet spinning, etc. ). High
humidity usually occurs together with a high temperature. Under such conditions the human thermoregulation
mechanism is placed under extreme stress because at temperature close to that of the body the heat loss through
convection and radiation becomes very small, while the high humidity of the air hinders effective evaporation of
moisture from the surface of the skin. Therefore, the combination of high temperature with high humidity in
the room atmosphere produces a condition very unfavorable for the comfort of human beings.
Ayka Spinning department uses Central station type plant. In this type, there are two separate units. The
main plant consisting of fan, air washer and other accessories is located in a plant room which is outside the
conditioned space. The fan, air washer and circulating pump are all at floor level in a separate room. Only the
air distribution system is in the conditioned space. The air-circulating duct is in the conditioned space, usually
near the ceiling and often between the roof and the ceiling. Diffusers are provided in the duct at suitable spacing
to distribute the cool humidified air but they are not positioned evenly as possible in the conditioned space. So
that suspended particles are found all over the room. If there are more ducts around the blending feeder area
and the Automixer which produce more flies, the suspended particles will be reduced. We can adjust the
efficiency of underground suction system, i.e. increasing it, so that more flies can be sucked. We can also extend
additional ducts form the ceiling so that cool air will reach the operator.

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4. CARD or Tarak machine (Reiter model C7)
4.1 Introduction
Carding is the action of reducing tufts of entangled fibres into a filmy web of individual fibres by
working the tufts between closely spaced surfaces clothed with opposing sharp points. Machines used to carry out
this work are called cards.
One of the main functions of a card is to disentangle tufts of fibre into a web of individual fibres. In this
respect, important considerations are the process of fibre individualization, the formation of the doffer web, the
fibre extent and configuration.
I Opening to individual fibres - Whereas the blow room only opens the raw material to flocks, the card
must open to the stage of individual fibres. This is essential to enable elimination of impur8ities and
performance of the other operations.
II Elimination of impurities - Elimination of foreign matter occurs mainly in the region of the taker - in.
Only a small part of the contaminants is carried along with the flat stripping, or falls out at other positions. The
degree of cleaning achieved by the modern card is very high, in the range of 80 to 95%. Thus, the overall degree
of cleaning achieved by the blow room and the carking room together is as high as 95 - 99%. Card sliver still
contains 0.05 - .03% foreign matter.
III Elimination of dust - 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 that are bound to the fibres. Significant fibre/
metal or fibre/ fibre friction is needed in order top loosen such particles. Both are available at the card in
considerable measure: the card is a good dust-removing machine.
IV Disentangling of neps - While the number of neps increases from machine it machine in the blow
room, the card reduces the remaining number to a small fraction. It is often falsely assumed that neps are
eliminated at the card; in fact, they are mostly opened out. Only a fraction of the neps leave the machine
unopened via the flat stripping.
V Elimination of short fibres - Short fibres can only be eliminated if they are pressed into the clothing.
Since that is not possible with metallic clothing, only the flats can be considered in this context. The ability to
select short as opposed to long fibres is based in the fact that ling fibres have more contact with the clothing of
the main cylinder than the short fibres. Thus longer fibres are continually caught and carried along by the main
cylinder. Short fibres, on the other hand, offer fewer surfaces to the clothing of the main cylinder; they therefore
stay caught in the flats clothing, press into it and leave the machine in the flat stripping.
VII Fibre orientation - The card ids often attributed the effect of parallelizing. This is not completely
justified, since the fibres in the web are not parallel, although they do have, for the first time, a degree of
longitudinal order. A parallel condition is achieved on the main cylinder, but it disappears during formation of
the web between the cylinder and the doffer. Thus, the card can be given the task of creation partial longitudinal
orientation of the fibres, but not that of creating parallelization.

33
E.G 2010/11
VIII Sliver formation - In order to be able to deposit the fibre material, to transport it and process it
further, an appropriate intermediate product must be formed. This sliver, in extreme cases, card sliver has a
hank of 3ktex (new spinning processes) or 6ktex. Generally the hank lies between 4 and 5.5 ktex in the short -
staple-spinning mill.
Ayka has 19 electronically controlled high performance short staple carding machine. The setting (gap)
between machine elements, delivery roller speed, and cylinder speed can be controlled using control panel. In
addition, technical data like machine stoppage reason, number of can change production per shift, actual
production per hour, actual efficiency of machine can directly be gathered from the control panel.
Mostly, Ayka works with around 99% efficiency of the machine with normal delivery speed of 120m/mins.
One delivery of sliver is 4500meters with an average weight of 20.5 kg with CV% variation ranging from 1.1 to
3.3. It takes about 50mins to fill one can with no stoppage of operation.
Material is fed to each card form Automixer of blow room pneumatically. Wastes from flat, cylinder and
rollers are removed by suction to waste processing room. Waste value is usually 15 -17% of its feed material.
Since the production rate of a single card cannot match the blow-room output, several cards must be used
and linked to the blow-room in such a way that there is a uniform feed of the fibre mass to each card. Ayka has
13 cards in the row cotton processing section and another 6 cards in the dyed cotton processing section. Here if
the product passes through the carding mechanism and not through comber the waste of that sample can reach
up to 35%
Figures 4.1 and 4.2 illustrate that the tufts are transported pneumatically to each card via distribution ducting.
Each card has a chute feed system connected to the ducting. There are various designs of chute feeds, but their
working principles are basically similar. There is an upper and lower chute separated by a feed roller and beater,
and a pair of feed rollers is positioned at the end of the lower chute. Each chute has air-escape holes and a
pressure sensor fitted to control a preset compacted volume of tufts in the chute. The upper chute receives tufts
from the distribution ducting, and the transporting air is exhausted through the air-escape holes. The feed roller
and beater remove the material at a slower rate, enabling incoming tufts to build up in this top chute. As the
tufts build up and cover the air-escape holes, the pressure sensor detects the associated increased air pressure in
the chute, and the tuft feed is closed off. As tufts build up in the top chute, the beater reduces the tuft size and
feeds the smaller tufts to the bottom chute. Here, the compaction of the tufts is by air pressure from a fan
C 7card
Figures 4.1 Overview of blow room to card machine

34
E.G 2010/11
blower. The rate of removal of the compacted material by the pair of feed rollers is slower than tuft feed, and,
much as with the top chute, a pressure switch controls the feed by stopping and starting the upper feed roller.
The waste level of the card machine is predetermined by the production controlling department and it is
pre set to 5-7%. This can be achieved by feeding the data to the control panel of the card machine. The control
unit then adjusts the settings between machine components.
.
4.2 Operating Principle
The material (cotton, viscose staple fibre, polyester, or any blend of these fibres) to the card is supplied
through a pipe ducting into the feed chute of the card. A portion of the feed chute is transparent for inspection.
An evenly compressed batt is formed in the chute. The linear density of the batt ranges from about 500 to
900 ktex. Obviously, the width of the chute will be about the working width of the card for maximum feed.
The weight of the batt with the downward guidance of the transport rollers found at the entrance of the card
just below the chute feed, the batt is transported to the feed roller and feed plate.
The chute has pressure sensors o maintain the evenness of the material. If there is anything wrong and the
pressure is lower, the display unit displays ―feed weight too small‖ if there is no feed ―empty airofeed‖.
The feed arrangement or feeding device consists of a feed roller and feeder plate. This pushes the sheet of
fibres lowly into the operating region of the licker-in. the feeding device should maintain an optimum pressure
otherwise the above error message will be displayed and machine stops. This section is transparent for
inspection and maintenance.
The sheet of fibres which projects from the feed roller is combed through and opened to flocks by licker-
in. this operation is performed by sow tooth wires wound onto the licker in on its surface. The licker in runs at
very high speed up to 600rpm.
The flocks pass over mote knives and grid bars found under the licker in. In so doing the materials are
separated from large impurities.
FIGURE 4.2 Short-staple carding
FIGURE 4.3 Basic features of a short-staple chute
line

35
E.G 2010/11
Suction ducts carry away the waste generated. The cylinder is covered with sow tooth type wire with
density of about 400-1000 wire points per square inch. The cylinder has diameter about 50‖ and rotates at a
speed of 359 to 400 rpm.
The flat and carding bars have a width of about 1‖ extending over the width of the card. The upper surface
of the cylinder is covered with approximately 100 individual flats but it depends on the accuracy of the counting
since it is hard to count it while moving because it is hard to locate the flat u started counting on. The individual
flats are joined by a chin making an endless chain rotating at a slow speed. The surface facing the cylinder is also
covered with metallic covers.
The setting between the flat wires and the cylinder wires are very, very close. Perhaps it is the closest setting
in spinning machines. This is vey critical for carding action expected form wire points.
The flock of fibresfrom the licker-in are carried away by the wire points of the fast rotating cylinder. The
flocks penetrate into the flats and open up to individual fibresbetween the cylinder and the flats.
A stripping device (cleaning device) strips the embedded wastes (short fibresand impurities) from the
individual flats. The bottom portion of the cylinder is also covered by grids or cover plates.
After the carding operation is completed, the fibresare carried on the surface of the cylinder. The fibresare
loose (not held except the loose frictional contact) and lie parallel on the surface. However, at this stage, the
fibresdo not form a transportable intermediate product.
A doffer runs at a substantially slow speed slow speed. This collects the fibreslaying on the surface of the
cylinder into a web. The calendar roller compresses the sliver to some extent. The coiler deposits the sliver into
the can.
As the spinning department is divided into two parts, 13 card machines are located at section 1, i.e. white
cotton producing section and another 6 are located in section 2, i.e. section which processes blended, dyed and
Man made cotton (Viscose).
Coiling
mechanism
Cylinder under
casing
Figure 4.4 A) card machine overlay with position of the sensors (dots)
B) Inside parts of card machine

36
E.G 2010/11
4.3 Problems Observed
As carding machine is one of the most important machine in spinning it should be diagnosed regularly. One
of the problems observed is since card machines work non stop for almost all days of the week there is no
periodic maintenance done on them and only they are checked when ever low quality product is produced or
when the machine stops because of malfunctioning machine elements. This is not a good approach because the
machine elements are really expensive to purchase and since there is no educated personnel to do the
installation they also have to bring the personnel causing extra cost. Also if only checked when there is
deterioration of quality of product a lot of card sliver will be wasted.
4.4 Recommendations
The problem can be solved using a regular maintenance scheme like below for all card machines with in 3
weeks. The following table is recommended as a Maintenance plan for card machines of both sections.
Mc
no
W01
W02
W03
W04
W05
W06
W07
W08
W09
W10
W11
B12
B 13
B 14
B 15
B 16
B 17
B 18
B 19
WEEK 1
M Tu W T F S Su
M I I I I I I
I M I I I I I
I I M I I I I
I I I M I I I
I I I I M I I
I I I I I M I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
WEEK 2
M Tu W T F S Su
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
M I I I I I I
I M I I I I I
I I M I I I I
I I I M I I I
I I I I M I I
I I I I I M I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
WEEK 3
M Tu W T F S Su
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
M I I I I I I
I M I I I I I
I I M I I I I
I I I M I I I
I I I I M I I
I I I I I M I
I I I I I I M
A regular inspection (I) is necessary activity to avoid end breakage. This activity also includes routine
servicing including lubrication, adjustments, and cleaning. This includes replacement of damaged bolt,
mending and repairing protection devices. All this activities should be documented for proper maintenance
store keeping and for further use. Major maintenance (over haul) which includes complete dismantling of
machine and checking all machine settings and accuracy of measuring devices should be done for a machine
twice in a year. In the above table (W) shows card machines in section 1, and (B) indicates card machines in
section 2.
According to the plan a machine should be medium repaired (M) at least once a week, given the importance of
high productivity of Card machine; it is not economical to stop more than one machine in a day.
Table 4.1 Maintenance Plan for card machine
Mc
no

37
E.G 2010/11
5 Draw Frame (Jer Machine)
5.1 Introduction
Draw frame is a very critical machine in the spinning process. Its influence on quality, especially on
evenness is very big. If draw frame is not set properly, it will also result in drop in yarn strength and yarn
elongation at break. The faults in the sliver that come out of draw frame can not be corrected. It will pass into
the yarn.
Objectives of the Draw Frame
Improving material Evenness - Draw frame primarily improves medium term and especially long term
sliver evenness through doubling and drafting. The number of doublings lie in the range 6 to 8 and so is the
range of draft; as a result, the input and output material is almost same in terms of liner density. Drawing is
done in two stages; at breaker and at finisher draw frames. Therefore, two passages of drawing with eight ends
(sometime six) each time would produce a single sliver consisting of 64 strands. This helps in reducing
variations.
Parallelization; - To achieve an optimal value for the strength of yarn, fibres must be arranged parallel to each
other and along the axis of yarn. Draw frame fulfils this task by way of the drafting by rollers. The amount of
draft to be applied immediately after the card cannot be very high as fibre entanglement is very high and the
strand is thick. As such, draft has to be increased gradually.
Mixing and Blending; - Drawing is the final stage of quality improvement in a spinning plant before yarn is
spun. This is by providing the 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. At the draw frame, metering of the individual components can be carried out. As an example, to obtain
a 67: 33 blend, four slivers of one component and two of the other are fed to the draw frame. However, these
slivers must have the same linear density. In the case of differences in linear density, thin slivers will not be
gripped properly by the drafting rollers, and disastrous results will be seen due to a group of some fibres drafted
away by the front rollers giving very high irregularity and fibre clusters in the drafted strand.
Dust removal; - Draw frame is a machine where a very high degree of fibre/fibre friction takes place in
the drafting zone; this is ideal for separating dust. Ayka draw frames have appropriate suction removal systems;
more than 80% of the incoming dust can be extracted.

38
E.G 2010/11
5.2 Parts of Draw Frame
5.2.1 Creel
The creel helps feeding the material to the drafting region. It must be designed in such a way to: Prevent
false draft and Provide stop motion to stop the machine in case any one sliver is absent. The slivers from the
creel should enter drawing zone closely adjacent to each other, but not on top of each.
In order to avid false draft the Ayka draw frame machine creel is positively driven i.e. it gets motion
conveyed from the main motor and not rotated from friction between the sliver and the metal surface. It also
has a heptagonal shape to effectively carry and transport the sliver to the drafting system and also avoid slippage
at the same time. The top rollers move by a friction between the sliver and roller surface. There is sensor o
detect whether there is a sliver present or not in top rollers. It works by detecting where there is metal to metal
contact, between top and bottom rollers and if there is contact, the solenoid will send a signal to the central
processing unit and automatically stops the machine signalling the operator to take necessary measures. Each
feed has its own creel. Jer machine has 8 feeds it has 8 creels though operators use only 6 feeds.
5.2.2 Drafting arrangement
Drafting arrangement is the heart of a draw frame. The drafting arrangement is Simple, Stable design for
smooth running at high speeds, Flexible to handle different types of fibres, Able to control fibres properly to
produce a uniform sliver, Easy to adjust in all drafting arrangements. Ayka draw frames fulfil all this
requirements by the help of electronically controlled speed changer and which show real time status using
control panel.
A B
Fig 5.2 different kind of rollers
Fig 5.1 creel

39
E.G 2010/11
Fig 5.4 Delivery and coiling
Bottom rollers are made of steel and mounted in roller, ball bearings. They are positively driven. These
rollers have one of the following flutes. Spiral-fluting (A) rollers are used mostly. Top rollers can roll on spiral
fluted bottom rollers more evenly and with less jerking and therefore spiral fluted rollers are preferred for high
speed operation; also they are used on rollers receiving aprons. Moreover, any defects in a flute spread out
helically in the drafted material and in subsequent drafts get distributed uniformly along the length. That is why
the first two bottom rollers are spirally fluted. The second pair bottom rollers are horizontally fluted (B) since
there is less material flowing and more of parallel web of fibres is needed. The diameter of the bottom rollers is
50 mm. Top rollers are coated with synthetic rubber. The drafting system of the machine is 3 by 3, 4 top rollers
by 3 bottom rollers. There is a pressure bar between the third and forth rollers for better guidance of the fibres.
Any fibre presented to the nip of the front pair of rollers should be immediately accelerated by that pair of
rollers and no slippage should take place. Due to this reason, front roller should have a higher pressure.
However, too strong pressure increases the wear of elastic cover; more pressure is often applied with reduced
settings like rollers 3 and 4. As the settings become closer, it becomes necessary to increase the pressure due to
increase in drafting force; otherwise roller slippage will occur. Pressure on top rollers is applied by means of
Pneumatic pressure
5.3.3 Delivery and Coiling
Material coming out of the drawing frame does not have much
cohesion. As such, in high speed operation, drafted material is immediately
converged through a tube (1 in Fig D-3) and guided though the trumpet (2
in Fig D-3) into the calendar roller. The diameter of trumpet (d) depends
on the sliver linear density. Usually For synthetic fibres, bigger coiler tubes
are used. This will help to avoid coiler choking and kinks in the slivers
while coiling in the can. Condensing by calendar roller is necessary in order
to fill up the can with more material. While the sliver is deposited into the
can, both the can as well as the plate on the top, having a tube through
which the sliver travels, rotate; such rotation helps to deposit the sliver in the
1
1
2 3
4
Guiding and tensioning
area(outside drafting) Drafting area
1
1
2
1
Fig 5.3 drafting arrangement

40
E.G 2010/11
form of a cyclonical coil. The tube extends from the centre of the plate to the periphery. The circumferential
velocity of the deposition point is somewhat higher than the delivery speed, so that blockage of the sliver is
avoided.
However, difference should not be very high; as otherwise, it may lead to false draft. Coiling can be under
centre or over centre. In most of the modern machines, full cans are changed automatically with empty cans. In
some automatic can changing mechanisms, the cans are replaced when machine runs at full speed and in some
others; the machine is stopped during the changing of cans.
5.3 Operating Principle
There are two passages for the jer machine in the spinning mill. These are the barker draw frame which is
a set 2 of draw frame machines before combing machine and the finisher draw frame which includes also 2 draw
frame machines located after combing in section one of spinning machines. In section two since there are no
combing machines barker draw frame comes after card machine and processes dyed cotton with combed sliver
from section one is used for blending procedure.
Most of the improvement in fibre parallelization and reduction in hooks takes place at the first draw
frame passage than at the second passage. First draw frame passage will reduce the periodic variation due to
piecing. Therefore the life of servomotor will be more and quality of the sliver will also be good because of less
and stable variations. Material flow in both passages is identical inside the machine.
For combed material with four doubling is used, it is better to use two draw frame passages in order to
reduce long thick places in the yarn.
Card sliver (3) in can (1) form is a direct feed for breaker draw frame in both sections. The sliver is then
carried by a creel (2) and then by a series of guiding and tensioning rollers (4) to the drafting system. This 3 by 4
drafting system (6) attenuates and drafts the sliver to a value of 7.5 for cotton and 7.9 for polyester. Combed
sliver needs more draft ranging up to a total draft of 7.5 to 8 is used. A suction system (5) is used to clean the
drafting system and then store the waste in storage compartment in the machine. Then the drafted sliver goes to
the coiling arrangement (7) for easy transport. Coiler size is selected depending on the type of material processed.
For synthetic fibres bigger coiler tubes are used to avoid coiler chocking and kinks in the slivers due to coiling in
the can (10). There is a can changing mechanism (8) so that empty can (9) replace the full one by itself. The cans
have wheels to help the automation. The entire machine is powered by a motor located at the middle of the
machine (11).

41
E.G 2010/11
As mentioned above both passages have the same machines with slight difference. The finisher draw frame
has a servomotor which is used for precise control of main motor and an Open loop type Autoleveler control
system. When ever there is a problem in sliver weight, more than the preset tolerance, it stops the machine. A
measuring sensor is provided in the region of the in-feed for continuous detection of the actual value of sliver
weight. A control unit compares the result with the set reference value and amplifies the difference signal and
feed it to an adjusting device which finally converts the impulse to mechanical adjustment. The regulator
provides a variable speed either to the back or the front rollers to give the required draft when the measured
material reaches the point at which the draft is applied. This is seen on the machine control panel as below.
If there is an imbalance the lights (circles) flash signifying the machine trying to adjust. The numbers signify
the maximum and minimum extent of deflection from the intended value.
8
7
6
1
4
1
3
3
1
2
1
1
1
11
10
9
1
5
1
Fig 5.5 overlay of draw frame with sensor
positions (dots)
0
1
-23 +23
Fig 5.6 Autolevelling

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