Industrial training on amber denim mills limited

1 | P a g e
Department of Textile Engineering
Industrial Attachment
AMBER DENIM MILLS LTD.
Banglabazar, Gazipur, Bangladesh

2 | P a g e
AMBER DENIM MILLS LTD.
Banglabazar, Gazipur
View of Amber Denim Mills Limited
Prepared by:
Rakibul Hasan
ID: 113-088-041
Batch: 24th(WET)
Cell: 01930492011
Online published by:
Md. Israfil Alam Rana
Sr. Engineer
R&D
Cell: 01717123339

3 | P a g e
Supervising Faculty:
Dr. A.B.M. Abdullah
Professor
Department of Textile Engineering
Primeasia University
Banani, Dhaka
Industrial Supervisor:
Engr. Md. Kamruzzaman
D.G.M (Plant)
Amber Denim Mills Limited
Banglabazar, Joydevpur, Gazipur

4 | P a g e
 ACKNOWLEDGEMENT
“In the name of Allah, the most Merciful and Beneficent"
At first my gratefulness goes to Almighty Allah to give me strength and ability to complete this industrial
attachment. You have made my life more bountiful. May you name be exalted. honored and glorified.
Now, we wish to take this excellent opportunity to thank a lot of people who have assisted inspired us in
the completion of our training period.
We fell grateful to and wish our profound our indebtedness to Professor M.A. Khaleq.Dean&
Head,Department of Textile Engineering, Primeasia University for his kind approval of the thesis topic and
guidance during my study.
We would like to express our deepest sense of gratitude to our supervisor Professor Dr. A.B.M. Abdullah.
Professor, Department of Textile Engineering for his continuous advice, encouragement and guide to
make the industrial attachment.
We would like to express our deepest sense of gratitude to our Co-supervisor Sr.Lecturer Nayon Chandra
Ghosh, Department of Textile Engineering for his continuous advice, encouragement and guide to make
the industrial attachment.
We are thankful to our Md. Anwar Hossain, Assistant Professor, Department of Textile Engineering. For
his continuous advice, encouragement and co-operation to make the industrial attachment.
We would like to thank the management of the Amber Denim Mills Ltd. for giving our opportunity to
work on the different sections and helping our in every possible way. Our deepest appreciation goes to
Engr. Md Kamruzzamam, DGM, Amber Denim Mills Ltd. For his permission to conduct my industrial
training without which it would be uncompleted.
We are also thankful to Md. Shazzadul Islam, AGM(Dyeing), Amber Denim Mills Ltd. for providing the
required data and also for guiding in a profound way to complete our industrial attachment.
After him I would like to thank Mr. Rafat Bin Hasan and Mohammad Israfil Alam for their continuous
advice, encouragement and co-operation to make the industrial attachment.
We would like to thank our entire course mate in Primeasia University, who took part in this ,discuss
while completing the course work.
Finally , we must acknowledge with due respect the constant support and patients of my parents.

5 | P a g e
 CONTENTS
Table of Contents
 ACKNOWLEDGEMENT ...................................................................................................................................4
 INTRODUCTION.............................................................................................................................................9
COMPANY PROFILE..............................................................................................................................................11
1.1 ABOUT AMBER GROUP............................................................................................................................................11
1.2 ENTERPRISES OF AMBER GROUP................................................................................................................................12
1.3 AMBER DENIM MILLS LTD........................................................................................................................................13
1.4 COMPANY PROFILE .................................................................................................................................................15
1.5 WORK-TIME SCHEDULE OF THE FACTORY....................................................................................................................16
1.6 TYPE OF MACHINE USED..........................................................................................................................................17
1.7 FACTORY LOCATION MAP ........................................................................................................................................18
1.10 PRODUCTION PROCESS FLOW CHART .......................................................................................................................20
DENIM FABRIC.....................................................................................................................................................21
2.1 WHAT IS FABRIC?...................................................................................................................................................22
2.2 DENIM FABRIC.......................................................................................................................................................22
2.3 WHERE DID THE NAME “DENIM” COMES FROM?..........................................................................................................22
2.4 WHAT EXACTLY IS DENIM AND HOW IS IT MADE?.........................................................................................................23
2.5 WHAT WAS DENIM FIRST USED FOR? .........................................................................................................................23
2.6 DENIM PROCESS FLOW............................................................................................................................................24
YARN ...................................................................................................................................................................25
3.1 YARN QUALITY.......................................................................................................................................................26
3.2 SPECIALTY OF YARNS ...............................................................................................................................................27
3.3 TYPES OF YARN USED...............................................................................................................................................29
3.4 YARN COUNT USED.................................................................................................................................................29
3.5 SUPPLIER OF THE YARN............................................................................................................................................29
WARPING ............................................................................................................................................................30
4.1 WARPING .............................................................................................................................................................31
4.2 IMPORTANCE OF WARPING ......................................................................................................................................31
4.3 IMPORTANT REQUIREMENTS OF WARPING...................................................................................................................31
4.4 WARPING PROCESS INVOLVES ...................................................................................................................................31
4.5 TYPES OF WARPING ................................................................................................................................................32
4.5.1 Direct warping............................................................................................................................................32
4.5.2 Indirect warping........................................................................................................................................33
4.5.3 Ball Warping ..............................................................................................................................................33
4.6 DEFECTS & REMEDIES OF WARPING .........................................................................................................................34
4.7 DIFFERENCE BETWEEN HIGH SPEED WARPING AND SECTIONAL WARPING...........................................................................37
4.8 WARPING IN AMBER DENIM MILLS LTD......................................................................................................................37

6 | P a g e
4.8.1 Machine Specifications..............................................................................................................................38
4.8.2 Warping Section Layout.............................................................................................................................40
4.8.3 Machine Main Parts..................................................................................................................................41
4.8.4 Briefly Description of Different Parts.........................................................................................................41
4.8.5 Essential Features ......................................................................................................................................49
4.8.6 Calculations................................................................................................................................................50
DYEING ................................................................................................................................................................52
5.1 DYEING ................................................................................................................................................................53
5.2 OBJECTS OF DYEING................................................................................................................................................53
5.3 THEORY OF DYEING.................................................................................................................................................53
5.4 DENIM DYEING ......................................................................................................................................................54
5.5 DYES USE FOR DENIM :............................................................................................................................................54
5.5.1 Vat Dyes .....................................................................................................................................................55
5.5.2 Sulphur Dyes...............................................................................................................................................57
5.6 DENIM DYEING PROCESS.........................................................................................................................................58
5.7 ROPE DYEING ........................................................................................................................................................59
5.8 PROCESS SEQUENCE IN INDIGO ROPE DYEING IN DENIM ..................................................................................................61
5.9 PROCESS CONTROL OF INDIGO ROPE DYEING ...............................................................................................................64
5.10 SLASHER DYEING..................................................................................................................................................66
5.11 LOOP DYEING ......................................................................................................................................................67
5.12 DIFFERENCE BETWEEN SLASHER AND ROPE DYEING.....................................................................................................67
5.13 RELATIVE MERITS AND DEMERITS .............................................................................................................................68
5.14 DYEING IN AMBER DENIM MILLS LTD......................................................................................................................69
5.14.1 Machine Specification .............................................................................................................................69
5.14.2 Dyeing ......................................................................................................................................................70
5.14.3 Pure Indigo...............................................................................................................................................70
5.14.4 Topping ....................................................................................................................................................72
5.14.5 Bottoming ................................................................................................................................................74
5.14.6 Regular Dyeing Recipe .............................................................................................................................76
5.14.7 Equipments used in dyeing lab.................................................................................................................78
LONG CHAIN BEAMING........................................................................................................................................79
6.1 LONG CHAIN BEAMER .............................................................................................................................................80
6.2 PROCESS FLOWCHART FOR LONG CHAIN BEAMER........................................................................................................81
6.3 LONG CHAIN BEAMING IN AMBER DENIM MILLS LTD. ..................................................................................................82
6.3.1 Machine Specification................................................................................................................................82
6.3.2 Essential Features ......................................................................................................................................83
6.4 BRIEFLY DESCRIPTION OF DIFFERENT PARTS ................................................................................................................83
SIZING..................................................................................................................................................................86
7.1 DEFINITION ...........................................................................................................................................................87
7.2 OBJECTS OF SIZING .................................................................................................................................................87
7.3 CHANGES IN YARN DUE TO SIZING..............................................................................................................................87
7.4 TYPES OF SIZING ACCORDING TO APPLICATION ..............................................................................................................87
7.5 SIZE INGREDIENTS AND THEIR FUNCTION .....................................................................................................................88

7 | P a g e
7.6 CONTROLLING POINT OF SIZING ................................................................................................................................90
7.7 SIZING IN AMBER DENIM MILLS LTD. .........................................................................................................................91
7.7.1 Machine Specification................................................................................................................................91
7.7.2 Process Flow Chart ....................................................................................................................................93
7.7.3 Regular Sizing Recipe .................................................................................................................................93
7.8 SIZING .................................................................................................................................................................95
7.9 BRIEFLY DESCRIPTION OF DIFFERENT PARTS.................................................................................................................96
WEAVING........................................................................................................................................................... 100
8.1 WEAVING ...........................................................................................................................................................101
8.2 FLOW CHART.......................................................................................................................................................101
8.3 BASIC WEAVE DESIGNS .........................................................................................................................................102
8.4 CLASSIFICATION OF MODERN WEAVING MACHINES....................................................................................................103
8.4.1 Air-Jet Weaving........................................................................................................................................103
8.4.2 Projectile Weaving ...................................................................................................................................104
8.4.3 Rapier Weaving........................................................................................................................................105
8.4.4 Water-Jet Weaving ..................................................................................................................................106
8.5 WEAVING IN AMBER DENIM MILLS LTD....................................................................................................................107
8.5.1 Machine Specification..............................................................................................................................107
8.5.2 Looming...................................................................................................................................................109
8.5.3 Basic Motion ............................................................................................................................................109
FINISHING.......................................................................................................................................................... 117
9.1 DEFINITION .........................................................................................................................................................118
9.2 OBJECTS OF FINISHING..........................................................................................................................................118
9.3 TYPES OF FINISHING ..............................................................................................................................................118
9.4 FINISHING IN AMBER DENIM MILLS LTD. ..................................................................................................................119
9.4.1 Finishing ...................................................................................................................................................120
9.4.2 Mercerization...........................................................................................................................................129
9.4.3 Desizing....................................................................................................................................................132
9.5 REGULAR FINISHING & MERCERIZING RECIPE.............................................................................................................134
DENIM WASH .................................................................................................................................................... 135
10.1 DENIM WASHING...............................................................................................................................................136
10.2 TYPES OF DENIM WASH.......................................................................................................................................136
10.2.1 Mechanical wash ...................................................................................................................................136
10.2.2 Chemical wash .......................................................................................................................................136
10.3 DENIM WASHING IN AMBER DENIM MILLS LTD. ......................................................................................................137
10.3.1 Regular Recipe .......................................................................................................................................137
10.3.2 Machine Specification............................................................................................................................139
10.4 MOST COMMON DENIM WASHES ........................................................................................................................143
INSPECTION ....................................................................................................................................................... 148
11.1 INSPECTION IN AMBER DENIM MILLS LTD. ..............................................................................................................149
11.2 INSPECTION PROCESS ..........................................................................................................................................149
11.3 FABRIC DEFECTS.................................................................................................................................................150

8 | P a g e
11.4 DEPARTMENT WISE DEFECTS AND CODES NO............................................................................................................152
11.5 QUALITY ASSURANCE PROCEDURE .........................................................................................................................152
QUALITY ASSURANCE ........................................................................................................................................ 154
12.1 QUALITY ASSURANCE IN DENIM ............................................................................................................................155
12.2 HANDLING OF RAW MATERIALS IN GODOWN ...........................................................................................................155
12.3 APPROVAL OF RAW MATERIAL...............................................................................................................................156
12.4 WARPING .........................................................................................................................................................156
12.5 DYEING & SIZING ...............................................................................................................................................156
12.6 WEAVING .........................................................................................................................................................157
12.7 SINGEING..........................................................................................................................................................157
12.8 FINISHING .........................................................................................................................................................158
12.9 INSPECTION & PACKING.......................................................................................................................................158
12.10 WASHING AND SHADE GROUPING........................................................................................................................159
12.11 DISPATCH .......................................................................................................................................................159
RESEARCH & DEVELOPMENT (R&D)................................................................................................................... 160
13.1 R & D DEPARTMENT IN AMBER DENIM MILLS LTD. ..................................................................................................161
13.2 DEVELOPED SAMPLES..........................................................................................................................................162
13.3 NAME OF SOME BUYERS ......................................................................................................................................163
TESTING LAB ...................................................................................................................................................... 164
14.1 QUALITY ...........................................................................................................................................................165
14.2 DENIM QUALITY ................................................................................................................................................166
14.3 QUALITY TESTING...............................................................................................................................................166
14.4 INTERNATIONAL STANDARDS ................................................................................................................................167
14.5 AQL – ACCEPTED QUALITY LEVEL..........................................................................................................................167
14.6 TEXTILE TESTING & QUALITY CONTROL...................................................................................................................168
14.7 SCOPE OF FABRIC TESTING ...................................................................................................................................168
14.8 LAB TEST CAPABILITY ..........................................................................................................................................171
14.9 MACHINE USED IN TESTING LAB............................................................................................................................175
STORE & INVENTORY CONTROL ........................................................................................................................... 180
15.1 STORE AND INVENTORY CONTROL..........................................................................................................................181
15.2 SCOPE OF INVENTORY CONTROL.............................................................................................................................181
15.3 INVENTORY SYSTEM FOR RAW MATERIAL................................................................................................................181
15.4 INVENTORY SYSTEM OF SPARE PARTS .....................................................................................................................182
15.5 INVENTORY CONTROL OF FINISHED GOODS..............................................................................................................182
15.6 OTHER INVENTORIES ...........................................................................................................................................182
MARKETING ACTIVITIES....................................................................................................................................... 183
16.1 MARKETING ACTIVITIES .......................................................................................................................................184
16.2 PROCEDURE OF EXPORT BUSINESS BY AMBER DENIM MILLS LTD. ................................................................................184
UTILITIES............................................................................................................................................................ 186
17.1 DEFINITION .......................................................................................................................................................187
17.2 UTILITY DEPARTMENT OF AMBER DENIM MILLS LTD. IS RELATED TO THE FOLLOWING THINGS............................................187

9 | P a g e
17.3 WATER SUPPLY..................................................................................................................................................187
17.4 BOILER ............................................................................................................................................................187
17.5 GENERATOR ......................................................................................................................................................189
17.6 AIR COMPRESSOR...............................................................................................................................................190
17.7 DRYER .............................................................................................................................................................191
17.8 CHILLER............................................................................................................................................................193
17.9 HUMIDIFICATION PLANT ......................................................................................................................................194
EFFLUENT TREATMENT PLANT (ETP) .................................................................................................................. 195
18.1 INTRODUCTION ..................................................................................................................................................196
18.2 ETP IN AMBER DENIM MILLS LTD.........................................................................................................................196
18.3 OUTLET EFFLUENT PARAMETERS (BANGLADESH STANDARD).......................................................................................197
18.4 PROCESS FLOW CHART ........................................................................................................................................198
18.5 DESCRIBE THE PROCESS FLOW CHART ....................................................................................................................198
SECURITY ........................................................................................................................................................... 201
19.1 SECURITY SECTION..............................................................................................................................................202
19.2 SECURITY MAIN GATE .........................................................................................................................................202
 DISCUSSION............................................................................................................................................... 203
 SOME SUGGESTIONS: ................................................................................................................................ 203
 LIMITATIONS OF THE REPORT: .................................................................................................................. 204
 CONCLUSION............................................................................................................................................. 204
 REFERENCES .............................................................................................................................................. 205
 INTRODUCTION

10 | P a g e
If the theoretical knowledge is a prescription of medicine then the practical knowledge
would be taking of medicine.
It is always very easy to make a man understand about a firebox by showing and lighting
practically
Rather than describing theoretically who has not ever seen a firebox. So, for any technical
education the practical experience is the most important as well as the theoretical
knowledge.
As we are studying in a technical line, it is always important for us to gather the practical
knowledge.
Through our study life the only biggest chance for us to combine the theoretical
knowledge with the Practical knowledge is the “Industrial Attachment Period” that comes
only once in the education life when completing under graduate education.
So we can easily realize the importance of Industrial Attachment. And in addition the
knowledge we gathered from the industrial training reflects in the report of industrial
attachment note book.
So industrial attachment is the process where a trainee can blend his theoretical
knowledge with practical knowledge which increased the ability of work, skills,
performance and attitude and so on.
It also provides sufficient knowledge about production management, productivity
evaluation, work study & efficiency, industrial management, production planning and
control, production cost analysis, inventory management, utility, maintenance and so on.
Industrial attachment makes us reliable to be accustomed with the industrial atmosphere
and also improve courage and inspiration to take self responsibility.
I have tried to my best to prepare this note book applying our best efforts. I have tried to
gather all the necessary information to make it a valuable for me as well as for everyone.
I think it will help me a lot in future practical life.

11 | P a g e
Chapter One
Company Profile
1.1 About Amber Group :

12 | P a g e
Mr. Showkat Aziz Russell
Chairman of Amber Group
Amber Group was established in 1996 and began its journey with Amber Cotton Mills
Limited. The group flourished with its gradual demand in the market. Apart from cotton,
other successful areas where the group operates include denim, board and doors,
Internet gateway, radio, lifestyle shopping outlet and leisure resort etc. The process of
establishing a television channel in ongoing. Backed by a high density of advanced
technology and sophisticated manufacturing facilities, Amber group is being managed by
highly qualified technical and management professionals. The excellence of the
technology and blooming genius of its personnel are the strength of the organization.
Amber Group with its various interests is rolling ahead with drive and determination to
be the best in all the areas it operates.
1.2 Enterprises of Amber Group :
 Amber Cotton Mills Limited
 Amber Denim Limited

13 | P a g e
 Amber Denim Mills Limited
 Partex Rotor Spinning Mills Limited
 Partex Rotor Mills Limited
 Amber Board Ltd.
 Amber Lifestyle
 Amber Radio
 Amber IT
 Bhawaal Resort
1.3 Amber Denim Mills Ltd. :
Amber Denim Mills Ltd. is one of the major concerns of Amber Group. It is a premium
denim fabric producing company. It has started its journey in 2012 with the best and latest
machinery available in the world. The current capacity is two million yards of finished
fabric per month.
Figure: Front View of Amber Denim Mills Ltd.
On the fabric side, product range of ADML includes weights from 4.5 oz. up to 14.5 oz.
using multi count, multi-twist ring, open-end yarn using CAIPO technology. It has a world’s
best MORRISON Indigo dye range from USA, which is capable of doing color like
bottoming, topping, reactive colored denim, Sandwich and very deep indigo shades.

14 | P a g e
Figure: Weaving Section Figure: Dyeing Section Most modern
Weaving is done on machines from Picanol from Belgium. ADML uses the most modern
weaving machine in air-jet version to get good productivity and to make trouble free
fabric even if it is made with coarser slub or spandex. The loom shed is totally humidified
and temperature controlled with enough air circulation and sufficient pressure to help
machine and yarn to make better fabric and always make the shed clean.
On the finishing side, ADML has machine from MORRISON textile co. of USA, which is the
most modern finishing range introduced in Bangladesh for the first time by Amber.
Sufficient brushing, singeing in both side, high quality skew device, bigger padder,
sanforizer and compacting device to make the fabric more clean and maintain shrinkage
properly.
Amber was the pioneer of starting Flat finish fabric commercially in Bangladesh and is
capable of doing a variation in flat quality as per the buyer’s requirement. They can make
Soft Finish, Flat Finish, and Super Flat as well. This machine was specially designed as per
Amber‘s requirement. Amber gives importance to inspection machines also. To control
proper tension and easy handling Amber uses most modern machines with conveyer belt
with auto wrapping and packing.
On the quality side, Amber uses most modern and efficient lab instruments from Atlas UK
which is operated by trained technicians. The verivide Light box, Spectrophotometer,

15 | P a g e
Rubbing tester, Washing Fastness, Tensile strength etc. gives accurate results and helps
to keep quality good and more consistent.
The R&D department is independent and equipped to promptly invent new designs for
new fashion and develop buyer‘s requirement timely. This department keeps all
documents from dyeing recipe to fabric construction and keeps master roll to keep shade
in same consistent even over a longer discontinuity. Amber always researches to develop
new fashion as per the world requirement as well as to maintain comfort & durability.
Amber is manufacturing all kinds of denim fabrics in rigid and stretch in the following
versions: Non flat, Flat Super Flat, Resin coated, Pigment Coated, Over Dyed, PU Coated,
Ash Coloured, Reactive Coloured, ECRU & RFD Denim.
Amber always researches to develop new fashion as per the world requirement as well as
to maintain comfort & durability. Amber is manufacturing all kinds of denim fabrics in
rigid and stretch in the following versions:
 Non flat
 Flat Super Flat
 Resin coated
 Pigment Coated
 Over Dyed
 PU Coated ECRU Denim RFD Denim
 Ash Colored Denim
 Reactive Colored Denim
 Color Denim
Amber is manufacturing bi-stretch commercially for the first time in Bangladesh. There is
no end in fashion. They are also in the process of making Linen Denim, Viscose denim,
and so on.
On the environment side, Amber maintains a state of the art Water and Effluent
Treatment Plant meeting toughest international standards, and always looks to make the
working environment greener. It has plenty of lush trees surrounding the plant premises.
Amber maintains labour laws, gives all facilities like medical, housing, leave, festival bonus
etc. to their employees.
1.4 Company Profile :

16 | P a g e
Company Name AMBER DENIM MILLS LTD
Company Status Private Limited Company
Owner Md. M.A.Hashem
Managing Director Md. Showkat Aziz Russell
Factory Location Jangaliapara (Banglabazar), Mirjapur,
Joydevpur, Gazipur-1700.
Corporate Office House: 02, Road: 09, Block: G, Banani,
Dhaka
Type of Factory Fabric Manufacturing
Product Denim Fabric
Capacity 2.1 million yards per month
Project Cost 31.6 million US dollar
Total Area 323000 sft
Production Area 270000 sft
Structure Steel structure surrounded by brick wall
Total Manpower 1144
1.5 Work-Time Schedule of the Factory:
The factory runs 24 hours a day. It maintains a tight work schedule. It follows mainly 3
schedules. i.e. A-shift: 6 a.m. - 2 p.m., B-shift: 2 p.m. - 10 p.m. & C-shift: 10 p.m. - 6 a.m.

17 | P a g e
Section Number ofShift Duration
Warping 2 12 hours each
Dyeing 3 8 hours each
LCB 2 12 hours each
Sizing 3 8 hours each
Weaving 3 8 hours each
Finishing 2 12 hours each
Utility 3 8 hours each
Security 3 8 hours each
Stuff &Commercial General Shift 9 a.m. – 5p.m.
Top Management General Shift 9 a.m. – 5p.m.
It is to be noted that 35% workers are working here in 3 shifts and 65% workers are
working in 2 shifts.
1.6 Type of Machine Used :

18 | P a g e
Section Machine
Name
Brand Name Origin Model Qua
ntity
Warping Ball Warping
Sectional Warping
Morrision
KARL MAYER
USA
Germany
450 BW
N/A
04
01
Dyeing Rope Dyeing Morrision American N/A 01
LCB Long Chain
Beaming
Morrision USA MDS-RB 550 12
Sizing UKL Sizing m/c
Karl Mayer Sizing
m.c
UKIL Mechinery
KARL MAYER
Korea
Italy
GSSM-100
BM 2600/1000
02
01
Weaving Air jet m/c PICANOL Belgium OMNI Plus 800 180
Finishing Finishing m/c
Mercerize m/c
Morrision
N/A
USA
China
N/A
N/A
02
01
Washing
Washing m/c
Dewater m/c
Laundery Sryer
m/c
YILMAK
N/A
N/A
Turkey
China
N/A
HBM 250S
KZ-20A
GDZZ-25
01
01
01
1.7 Factory Location Map:

20 | P a g e
1.10 Production Process Flow Chart:
Ball Warping
Rope dyeing
Long Chain Beamer
Sizing
Drawing-In
Weaving
Finishing
Inspection
Packing

21 | P a g e
Chapter Two
Denim Fabric

22 | P a g e
2.1 What is Fabric?
The word "textile" comes from the Latin "texere", "to weave." It originally meant a fabric
made from woven fibers. Today, the word "textile" includes fabrics produced by felting,
weaving, knitting, and knotting fibers. It also refers to man-made fabrics which may be
produced by other methods.
2.2 Denim Fabric :
Denim is a cotton or cotton/polyester blend, durable heavy weight twill weave yarn dyed
fabric. Usually the warp is colored and weft is white. It is often right-hand twill with a blue
(indigo) warp and white weft for use in apparel in a variety of weights. Since it is a warp-
faced twill, the colored warp yarns predominate on the face and the white weft yarns on
the back. It is available in several weights, ranging from 4.00 oz/yd2 to 16.0 oz/yd2 in a
2/1 or 3/1 interlacing pattern basically. Its long term popularity has made it a fashion
fabric in casual wear. It may be napped, printed, made with spandex or other stretch yarns
or otherwise modified for fashion. Even today, classic denim is still dyed with indigo dye.
2.3 Where did the name “Denim” comes from?
Denim (French town of Nîmes, from which 'denim' (de Nîmes) gets its name) is a rugged
cotton twill textile, in which the weft passes under two (twi-"double") or more warp
threads. This produces the familiar diagonal ribbing identifiable on the reverse of the
fabric, which distinguishes denim from cotton duck. Denim has been in American usage
since the late 18th century. The word comes from the name of a sturdy fabric called serge,
originally made in Nîmes, France, by the André family. Originally called serge de Nîmes,
the name was soon shortened to denim. Denim was traditionally colored blue with indigo
dye to make blue "jeans", though "jean" then denoted a different, lighter cotton textile;
the contemporary use of jean comes from the French word for Genoa, Italy (Gênes),
where the first denim trousers were made.

23 | P a g e
Figure: Classic Denim (indigo dyed)
2.4 What exactly is Denim and how is it made?
Denim is a rugged cotton twill textile, in which the weft passes under two or more warp
fibers. This produces the familiar diagonal ribbing identifiable on the reverse of the fabric,
which distinguishes denim from cotton duck. It is a twill-weave woven fabric that uses
different colors for the warp and weft. One color is predominant on the fabric surface.
Because of this twill weave, it means the fabric is very strong. But today, denim is
diversified in many ways according to customer satisfaction and fashions.
2.5 What was Denim first used for?
Denim was originally used by workers. They wore denim clothes because of its durability,
it was extremely strong and perfect for their daily jobs, and it didn’t wear out easily
making it a good fabric for the long run.

24 | P a g e
2.6 Denim Process Flow :

25 | P a g e
Chapter Three
Yarn

26 | P a g e
3.1 Yarn Quality :
In order to produce good quality denim, the yarn quality used for denim production
should be optimal. In rope and slasher dyeing machine the passage of yarn is very
long. Hence it is necessary to control the lapping of yarn in the passage of yarn, otherwise
bands of high and low densities will be formed in the yarn, which ultimately cause shade
variation in the fabric. This leads huge loss of fabric. Therefore the TM of the yarn is to be
appropriate to avoid any snarling of yarn during running through the passage.
The yarn should be free of weak place, to avoid any breakages during dyeing. Long slub,
thick and thin places in the yarn may leads to prominent fabric defects in the fabric, as
denim is a contrast fabric made of indigo blue warp and grey weft yarn. The weft yarn
hairiness should be low, otherwise high yarn hairiness and major variation in yarn
hairiness shown weft bands which is a major fabric defects. Higher yarn neps may also
cause serious fabric defects.
The quality criteria of carded OE or ring spun yarns used for denim production are as
follows:
 Minimum staple length:2.7cm
 Short fibers proportion (less than 12 mm long)
should beunder 40%,
 Micronaire value should be 4.0 -4.5,
 Twist factor : 4.5 to 5.0, for warp yarns, 4.2 for filling yarn,
 Low yarn hairiness, low neppiness
 Good yarn strength and uniformity.
In the early 1990s, the majority of yarns used in denim production
were OE yarns. However, recently, there is a strong demand of using
more carded ring spun yarns in both warp and weft, which gives the
fabric a softer handle.

27 | P a g e
Warp yarns for bottom weight jeans typically range from Ne 4.0 to Ne 12.5/1 or as per
requirement of finished denim fabric. Finer yarns are used for lighter weight jeans, vests,
dresses, and skirts and the yarns range may be from Ne 12.5 to Ne 30.0.
3.2 Specialty of Yarns :
Modern ring-spinning frames and open-end machines can be installed with devices that
can manufacture predetermined yarn effects. These effects can vary from slubs (thick
places) with different lengths, different spacing between slubs, or variations in the yarn
count.
Fig: Yarn Winding Cones
Elastic Denim Yarns:
Core-spun yarns are produced conventionally on ring-spinning machines by introducing a
spandex filament at the back of the front drafting roll of the machine. The drafted cotton
fibers twist around the spandex core to produce an elastic ring-spun type yarn. There are
also open-end and air-jet spinning machines that have been adapted to produce core-
spun yarns. The core filament yarn (normally spandex) is inserted through the rotor shaft
on OE frame or the spindle of the air-jet frame, and the cotton fiber wraps around the

28 | P a g e
spandex filament during the process of spinning. The yarn is somewhat similar to the ring
core-spun yarns in term of yarn and fabric characteristics. Open-end and air-jet core-spun
yarns have fewer knots and splices as compared to ring core-spun yarn.
Lycra Yarn:
The picture shows that how the lycra yarn are stretched among the fibre and by force too.
That the dia reduces or decreases by the applied force that’s the speciality of lycra yarn.

29 | P a g e
3.3 Types of yarn used :
 Rotor yarn
 Ring yarn
 Slub yarn
 Polyester
 Lycra yarn
3.4 Yarn count used :
 For warp : 6, 7, 8, 9, 10, 12, 14, 16, 20, 30 (Slub +Normal)
 For weft : 6, 7, 8, 9, 10, 12, 14, 16, 20, 30 (Slub +Normal)
 Polyester : 300D,600D
 Lycra : 10L40D, 16L40D, 200L40D,300DL40D
3.5 Supplier of the Yarn :
 Partex Rotor Mills Ltd.
 Partex Rotor Spinning Mills Ltd.
 Amber Cotton Mills Ltd.
 Sapphire Textile Mills Ltd.
 Mahamud Denim Ltd.
 Nishat Mills Ltd.
 Shaoxing Xingji Import & Export Co. Ltd.
 Square Textile Ltd.
 Kader Synthetic
 Ashik Composite Textile Ltd.
 Purbani Rotor Mills
 Ashik Composite Textile Ltd.

30 | P a g e
Chapter Four
Warping

31 | P a g e
4.1 Warping :
The parallel winding of warp ends from many winding packages (cone, cheese) on to a
common package (warp beam) is called warping.
4.2 Importance of Warping :
 Construction of a beam of warp yarn.
 Construction of a parallel yarn sheet.
 Modifying the faults of yarn like thick or thin place.
 Winding the predetermined length of yarn.
 Combination of small packages.
 Accelerating the next process.
4.3 Important requirements of Warping :.
 The tension of all wound ends must be uniform and possibly constant during all
the time of with drawl from the supply package.
 Warping should not impair the physical and mechanical properties of yarn.
 The tension should be moderate to allow the yarn complete retain its elastic
properties.
 Predetermined length should be observed.
 Production rate should be high as possible.
 The surface of warping package must be cylindrical.
4.4 Warping process involves :

32 | P a g e
4.5 Types of Warping :
 Beam/Direct warping
 (Grey/Mono colour fabric)
 Sectional/Indirect warping
 (Warp patterns: Stripe sand Checks)
 Ball warping
 (Denim fabric)
4.5.1 Direct warping :
In direct warping, the yarns are withdrawn from the single-end yarn packages on the creel
and directly wound on a beam.
Direct warping can be used to directly produce the weaver’s beam in a single operation.
This is suitable for strong yarns that do not require sizing and when the number of warps
on the warp beam is relatively small. This is also called direct beaming. It can also be used
to make smaller, intermediate beams called warper’s beams. These smaller beams are
combined later at the slashing stage to produce the weaver’s beam. This process is called
beaming.
Figure: High speed/Direct warping

33 | P a g e
4.5.2 Indirect warping :
In Indirect warping, a section beam is produce first. It is also called band warping or drum
warping. The section beam is tapered at one end. Warp yarn is wound on the beam in
sections, starting with the tapered end of the beam. Each section has multiple ends that
are traversed together slowly during winding along the length of the section to form the
angle. Due to the geometry of the yarn sections, the last section on the beam will have a
tapered end that will make the whole yarn on the beam stable. It is important that each
layer on the beam contain the same number of yarns. The same length of yarn is wound
on each section. After all the sections on the beam are wound completely, then the yarn
on the beam is wound on to a regular beam with flanges, before slashing. This process is
called re-beaming.
Figure: Indirect warping
4.5.3 Ball Warping :
Ball Warping is mainly used in manufacturing of denim fabrics. The warp yarns are
wound on a ball beam in the form of a tow for indigo dyeing. After the dyeing process,
the tow is separated and wound on a beam. This stage is also called long chain beaming
or re-beaming.

34 | P a g e
Figure: Ball warping
4.6 Defects & Remedies of Warping :
1. Lapped end
Cause:
The broken end of yarn is not tied to the end on the warp beam & overlaps the
adjoining yarn. The beam is not properly brake & the signal hook fails to operate.
Remedies:
 Tying the broken end to the end on the warp beam.
 Proper signal hook.
2. Piecing
Cause:
One broken end is pieced to another yarn end on the warping beam.

35 | P a g e
Remedies:
 By proper joining.
3. Soft ends on the warping beam
Cause:
Breakage of a group of ends & piecing them in bundle or by lapping. This defect is
caused by the careless of the operator.
Remedies:
 Careful operation.
 Broken end should be piece up properly.
4. Incorrect form of build
Cause:
Caused by non uniform spreading of ends in the guide reed & its improper setting &
conical winding in case of non uniform pressure of the warping beam.
Remedies:
 Uniform spreading of ends.
 Appropriate setting.
5. Slacks & irregular yarn tension
Cause:
It happens due to any one of these reasons- improper threading of the yarn into the
tension devices, ejection of yarn from under the disc of the yarn tensioning device, or
yarn tension devices of poor quality.
Remedies:
 Proper threading of tension device.
 Good quality of tension device.
6. Broken ends on the beam
Cause:
A group of ends is broken & tied as a brunch or worked-in with overlapping.

36 | P a g e
Remedies:
 Broken ends should be removed.

7. Conical winding on the beam
Cause:
It occurs due to incorrect load applied by the pressure roller.
Remedies:
 Correct load applied.
8. Improper length of warping
Cause:
It is due to malfunction of the counter & the brakes of the measuring device & warp
beams.
Remedies:
 Good measuring device.

37 | P a g e
4.7 Difference between High speed warping and Sectional warping :
High speed warping Sectional warping
To produce common fabric To produce fancy fabric
High production Low production
Large no of yarn are required Small amount of yarn are required
Weavers beam is produced after
sizing
Weavers beam is produced before sizing
Creel capacity is greater than1200 Creel capacity is greater than 300 to400
Cone, cheese winding are used Flanged bobbin is used
Single yarn is used Twist yarn is used
Cheap process Costly process
Uniform tension Not uniform tension
Used very much Not used
4.8 Warping in Amber Denim Mills Ltd. :
The warping section of the Amber Denim Mills Ltd. is working under the A.G.M. of
Preparatory Section. MDS-BW 450 warping machine with Custom Magazine Creelis used
here. The department is connected with dyeing section directly and working 24 hrs. R&D
department inspects the cones which is converted in beams of required length and
forwarded to dyeing section.

38 | P a g e
4.8.1 Machine Specifications :
NAME : MORRISION BALL WARPINGMACHINE
Total Machine :04
Model : MDS BW 450
Origin :USA
Year of Installation :2012
Creel capacity : 456
Winding Speed : 250-300m/min
M/c Speed r.p.m 450 BW
Line Speed 290 (mpm)
Lease Interval Max 1000 & Min 500 m
Maximum Beam Diameter : 1200mm
Air Pressure Required : Max 34 & Min 29.9 PSI
Maximum Length of Yarn Can Wind : Around 12000m
Yarn Count : Both Ring & Open End yarn

39 | P a g e
NAME KARL MAYER SECTIONAL
WARPINGMACHINETotal Machine 01
Type ERGOTEC-M 2000/1000
Origin Germany
Year of Installation 2014
Creel capacity 720
Winding Speed 400m/min
M/c Speed r.p.m 450 m/mim

40 | P a g e
4.8.2 Warping Section Layout :
Total Area = 20000 sft
A= Exit
B1,B2,B3,B4= Morrision Bal Warping Machine
C=Wall
D=Sectional Warping Machine

41 | P a g e
4.8.3 Machine Main Parts :
 Creel Section :
Bobbin Stand/ Package Stand Holder
Plastic Disk
Post
Post Controller
Sensior
Ciramix Guide
 Reed :
Control Box
 Pulley Stand
 Head Stock :
Motor
Counter Roller
Traverse
Hook
Pressure Roller
4.8.4 Briefly Description of Different Parts :
Creel
In ball warping, all the packages are loaded into the adapters of the creel of ball warping
machine. The creel is normally designed to accommodate about 330 to 430 packages.
The creel may be of different types, such as Magazine Creels and Traveling Package
Creels. The passage of yarn in ball warping are shown in Fig. 1
Fig.1 : Passage of yarn in ball warping

42 | P a g e
Fig. 2: Ball Warping Machine
The Magazine creels are straight-line creels having a reserve yarn package placed beside
the running packages (Fig. 3). The tail end of the running package is knotted with the start
end of the reserve package. When the running package is depleted, the warper continues
to run with the from the reserve package.
Fig. 3: Magazine Creels

43 | P a g e
The traveling package creels are V-shaped creels. The running yarn packages are kept on the
outside of the V and the full yarn packages are loaded on the inside of the V. When the
running packages are emptied, the yarn spindles on the creel are rotated so that the full
packages move to the outside of the creel and the empty packages move towards the inside
of the V-creel for replenishment. The warping machine is start with the new yarn ends. The
empty packages are unloaded and replaced with new full packages.
Fig : Ball Warping Logs
Tensioners
The individual yarn from each package loaded in the warping creel are passes through a
tensioner. There are different types of tensioners available for ball warping machines. The
different types of tensioners are as below:
Fig.: Typical Yarn delivery to the warp preparation machines

44 | P a g e
Post and disk tensioners: This type of tensioner unit two or three posts fitted onto a flat
base. Two round disks are placed onto each post. The yarn is passes between the disks and
wrapped around the posts. Out of the two or three post, one is movable. This varies the
angle of wrap, which apply different levels of tensions to the yarn. The tension on the yarn
can be increased by adding weights onto the op weights. This type of tensioners is
inexpensive, simple to thread up, require less maintenance. However the yarn has a
tendency to jump up out from between the disk, it is very labour intensive to change the
tension levels to the yarn.
Driven disk tensioners: This type of tensioners has a twin-disk arrangement. The disks are
supported from below and the tension is applied from above the disk through weights or a
spring loaded device. A gear under each pair of disk is matched to another gear. This gear is
mounted on a continuous shaft which is connected to a motor to rotate the disk. In some
latest machinery manufacturer incorporates 4 RPM motor per post for disk drive. The
rotation of the disk prevents thread cutting and dampens due to ballooning of the yarn. This
type of tensioners requires less effort to change tension levels. However it requires more
maintenance due to maintenance of the electric motor.
Fig.:Typicaldrivendisktensioner,TensionRange:10-150grams,OperatingSpeed:
0- 1,500 MPM, 4 RMP Gear Motor per post

45 | P a g e
OZ Tensioner: The OZ tensioners is very simple and popular in different denim production.
The tensioners consist of a cylindrical housing which is fitted with small ceramic eyelet at
the top and bottom. There are two steel balls inside the housing. The yarn is threaded up
through the bottom eyelet, around the steel balls and out through the top eyelet. The
tension is applied to the yarn as it passes around the steel balls. The tension on the yarn is
higher at the rear of the creel due to distance of the yarn travel and lower at the front of
the creel due to the same reason. At the rear of the creel, the balls are prevented for giving
much tension to the yarn, as the yarn already has higher tension. However, at the front of
the creel, the yarn tension is less. The balls exert higher pressure to the yarn as it passes
between them. Hence the tension across the yarn sheet remains equal.
The advantages of this type of tensioners are minimum maintenance required and no
adjustments required in this system. However, there is a limit of how much tension can be
applied to the yarn. It is difficult for threading and it is relatively expensive.
Electronic Tensioner: The electronic tensioners are of two types, such as: Capastan Type
and Rotating Disc Type.
In the Capastan type of tensioner, a round capastan fitted on a precision shaft. The capastan
is fitted onto the bearings located inside of a round DC coil. The yarn is wrapped around the
outer surface of the capastan and when the yarn is pulled out, the capastan rotates. An EM
field is created under the capastan if no voltage is applied to the DC coil. A hysterisis ring
attached to the inside of the capastan, reacts with the EM field and a resistance is created
against the free rotation of the capastan. This resistance incorporates tension to the yarn.
In order to achieve equal tension to each yarn, varying levels of DC voltages are applied to
each tensioner. The advantages of this type of the tensioners are less maintenance
required, no use of electric motor.
In the Rotating Disc type on the same principle, but it applies tension in different way. Two
disks are fitted in the vertical position onto a ceramic shaft. Inside disk, there is a DC coil.
An electromagnetic field is generated when voltage is applied to the DC coil. The outside
disk is attached to the magnetic field and pulls tightly against inner disk. It applied tension
to the yarn threaded between the two disks. The amount of tension depends upon the
strength of the EM field created by the DC coil. A 4 RPM AC motor fitted on each tensioiner
turn the disks to avoid thread cutting.

46 | P a g e
Stop motion devices
A stop motion device is fitted in the creel to stop the machine at the event of any end
breakages. There are different types of stop motion devices available. However each of
them having their own advantages and disadvantages. Some of stop motion devices are as
below:
Drop wire stop motion : It is fitted on each vertical row at the front of the creel bands.
This is the simplest type of stop motions. A drop wire is placed onto each yarn end. There
is an exposed electric contact bar beneath the drop wires. An open electric circuit is
maintaining in the electric contact bar in normal running condition. However at the time
of any end breakages, the drop wire falls onto the contact bar and shorts out the circuit.
This system is very inexpensive and very fast reacting. However, the system is exposed to
dust, lint and short fibers. If the contact bar is accumulated with fluff, the drop wire will
not be in contact with the bar and the system remains open.
Photoelectric stop motion : This type of stop motion works on almost in same principle as
the drop wire type, but there is some difference. The photoelectric system uses a faller
which is attached to a shutter inside of an airtight housing of the housing. Inside the
housing, there is a photocell having a transmitter at one end and a receiver at the other
end of the housing. A light beam is emitted to the receiver which maintains an open
electric circuit. At the time of an end breaks, the faller drops. This causes the attached
shutter passes through the light beam, which ultimately initiating the stop signal to the
warper. The system is reliable, inexpensive as compared to drop wire. It is easy to thread
and maintenance free. However, the system having disadvantages of residual tension on
the yarn which preventing the shutter to drop.
Electric Motion Sensor : In this system an electric motion sensor is fitted in the balloon
shield at the yarn cone. The system measures the motion of the yarn when it exits from
the cone. The yarn balloons housed in the balloon shield through a light beam. The system
remains open as long as the light beam is broken by the ballooning motion. At the event of
end breakages, the ballooning action immediately stops and the sensor signals the warper
to stop. This system is reliable, fast acting and self cleaning. But the system is expensive.

47 | P a g e
Lease Stand
After leaving the creel, the yarn passes through the reed of a lease stand. The lease stand
having two reed / comb, out of which one reed is movable up and down, which allows each
adjacent yarn end to raise or lowered to form a shed of yarn sheet. Each alternate yarn
threaded through alternate reed.
A lease string is inserted across the shed formed by the reed, at a specified intervals, may
be 1000 m. At this interval, the machines is automatically stops for lea insertions. However,
the intervals of lease may be varied within the rope, as per requirement of the technologist.
The lease helps in maintain proper leasing in subsequent process, i.e. in long chain beamer.
Any cross ends in the rope can be cleared at the lease portions. The operator in long chain
beamer can check whether there is any cross end at lease portions. Any broken end, missing
end can be properly mended at lease portions. Hence lease is an important consideration
in denim productions. Most of the denim technologist use cotton or synthetic filament yarn
for lease. The lease strand should not be of coarse count, or thick at any rope, which may
cause unusual end breakages in rope dyeing by touching in fingers.
Next the yarn passes through a counter stand or combination of counter stand and
condenser tube assembly. Here the yarn sheet is condensed into a bundle. From the counter
stand the yarn passing it through a funnel-shaped trumpet. It is located at the rear of the
ball warper. Here the total ends of the yarn sheet is collected in a rope form. This rope is
wound on a “log”.
In the ball warper, there are two motor driven drive rolls which are geared together. The
ball warping log is placed between these two drive rolls and held against the surface of the
drive rolls with pneumatic pressure. The log turns as the two drive roll runs. A pneumatic
brake attached to the drive rolls stops the rotation of the rolls as and when required or at
the time of any end breakages.
Ball warping machine normally uses a chain and dual sprockets in order to give side-by-side
motion of the rope during winding onto the log. This side-by-side movement of the chain is
provided through mechanical gear in the traverse to the drive roll motor. The traverse
movement of the chain is synchronized to the drive roll rotation speed. However, there is a
problem of ribbon formation in the log at certain diameter, as it is not possible to vary the
speed of rotation of the rope onto the log. The ribboning causes the machine to vibrate
until the rope achieve a somewhat more uniform surface across the log.

48 | P a g e
McCoy Ellison provides a separate AC Inverter controlled motors for the traverse and for
drive the rolls. Both are controlled by Programmable Logic Controller (PLC) so that the speed
of the traverse is not depends upon the speed of the drive rolls.
Ball Warper Gear-in speed
The maximum gear-in speed of the ball warper depends upon the desired production of a
mill. A typical speed is 360 to 400 m/min.
Ball windup
In the ball warping, the yarn passes through the traversing trumpet, which distributes the
rope onto the log. The ball warping machine should be such that, there is a minimum of
“dwell time” at the end of each traverse stroke. This prevents hanging of the yarn over the
ends of the ball and formation of any loops.
Ball dimension
The relationship between the ball dimensions and the corresponding length of yarn is an
important consideration during purchasing of ball warper. The ball length can be calculated
with the following formula by assuming a typical yarn density 59 cubic inches per pound.
Ball length in yards = {11.8 x yarn count x ball width x (D2 – d2)} / Endsper rope Where D=
Ball diameter in inches,
D= Log diameter in inches
Braking and start-up
At the time of any end breakage, the ball warping brakes are immediately activated by stop
motions. This sudden stoppage of the machine may leads to risk of scuffing the ball on the
driving drums, unless the brakes are synchronized properly. In the event of rapid start of
the machine, there is a chance of yarn scuffed. Some manufacturer incorporates synthetic
covered driven drums to minimize yarn scuffing and slipping.

49 | P a g e
Control Panel
Through the control panel the variation of speed and the panel are controlled through the
control panel.
4.8.5 Essential Features :
The essential features are:
 Heavy frame construction with polyurethane covered bed rolls ensures high speed
winding,
 The Smart Stop Technology™ activates brakes only on critical stops which maximizing
brake life,
 Controlled deceleration and Smart Lease Technology™ with creep speed avoids rope
(kinking) knotting during stops,
 Belt driven traverse system with speeds up to 10m/second and accelerations up to
40m/second
 Automatic speed profile of traverse servo drive is programmable for infinite speed
adjustment allowing variable ball patterns
 Full width Turn Around Stand allows even yarn tension and less lost ends

50 | P a g e
4.8.6 Calculations :
Some examples are given below to show the concept of warping plans.
Problem : 01
If Weight of Bag: 50Kg
Total Number of Cone: 24 Count: 7OE
Then find out the length of yarn in one cone.
Solution :
Per cone weight = total weight of cone /total no of cone
=50/24
=2.08333
Length of yarn in one cone = weight ×count
=2.08333×2.20462×840 × 7/1.0936M
=24695.1307M
Answer: Length of 7 OE = 24695M
Problem : 02
If Set length: 21000m
Count: 7 9 12
Ratios:4:4:4
Find out average
count.

51 | P a g e
Solution :
Average Yarn Count= 12 × 7 × 9 × 12 /4 × 9 × 12 + 4 × 7 × 12 + 4 × 7 ×9
=9072/432+336+252
=9072/1020
=8.894
Answer: Average Count =8.89
Problem : 03
If, Set length: 24695m
Total ends: 4464 Ends/beam:446
Total beam:10 Count: 7OE
Find out the weight of yarn
required.
Solution:
Weight of yarn in one beam =Set Length × Total Ends × 1.0936/840 × 2.2046 ×count
= 24695 × 446 × 1.0936/840 × 2.20462 ×7
=12044877.592/12963.1656
=929.16Kg
Total yarn required = Weight of yarn in one beam× Totalbeam
=929.16×10
=9291.61Kg
Answer: Total Yarn Required = 9291.61Kg

52 | P a g e
Chapter Five
Dyeing

53 | P a g e
5.1 Dyeing :
The process by which a textile material is to be changed physically or chemically, so that it
looks mono uniform colored is called dyeing. All commercial textile dyeing processes take
place by the application of a solution or a dispersion of the dyes to the textile material
followed by some type of fixation process. The dye solution or dispersion is almost always
in an aqueous medium. A major objective of the fixation step is normally to ensure that the
coloured textile exhibits satisfactory fastness to subsequent treatment in aqueous wash
liquors. Dyeing is mainly depends on the type of fabric, structure of fabric and the properties
of dyes.
5.2 Objects of Dyeing :
 The textile goods are dyed uniformly with single color.
 To increase the attractiveness of the textile goods.
 To make the fabric suitable for various usage.
 To make the textile goods suitable for decorative purposes.
5.3 Theory of Dyeing :
The procedure by which dye stuff enters into the textile goods is called theory of dyeing. It
is essential to have certain degree of fastness properties when a dye particle is applied on
textile goods. The whole process of dyeing is completed by four steps as follows:
 Dye molecules come to the fabric surface from the dye bath.
 Fibre absorbs the dye molecule from the outer surface of the fibre to the internal
surface of the cellulose.
 Migrates the dye molecules everywhere of the fibre molecules.
 Anchoring or fixing the dye molecules to the fibre molecules by hydrogen or covalent
bond.

54 | P a g e
5.4 Denim Dyeing :
The classical jeans were produced out of indigo-dyed Denim fabric. The special character of
this fabric – only the warp thread is dyed makes it necessary to carry out dyeing in yarn
form. The yarns applied for Denim were exclusively produced on ring spinning machines in
former times. The development of OE yarns by applying smaller rotors with a spinning speed
of up to 200 m/min has led to the application of OE rotor yarns both for warp and weft. The
yarns applied for weaving must be of high quality, a high fiber for strength, regularity as well
as a small part of short-stapled cotton fibres belongs to the basic features of the denim yarn.
For regular jeans qualities the warp yarns are spun in a fineness of 50 to 90 tex, for the weft
yarn the fineness ranges are mainly 75 to 120 tex. If Denim is made out of Tencel or Modal
especially for jeans shirts the finenesses are up to 25 tex. Indigo, sulphur and indanthrene
are mainly used in the dyeing process. Two methods are applicable for continuous dyeing
with indanthrene dyes: rapid dyeing and vat dyeing. While processing the basic colored
denim, reactive dyes are used and fixed with hot caustic soda solution. The dyeing process
is mainly influenced by the dyestuff characteristics, dyeing temperature and necessary
chemicals used in the process. Indigo dye is the most popular choice as it has good depth of
shade and suitable rubbing and washing fastness.
When cotton yarn is dyed with indigo, it leaves a ring-dyeing effect, because of which the
outer layer of warp yarn is coated with indigo, and the core of the yarn remains undyed.
This gives the denim garment a unique ‘faded look’ and a rich blue shade after repeated use
and wash. Originally, the warp yarns or ends were put through the dye bath side by side to
form a sheet of yarn, which passed continuously through several dye baths, squeeze rollers
or airing sequences. Specially two types of dyes are commonly used in factory. Vat dye and
sulphur dye. These two types of dyes are described below.
5.5 Dyes use for Denim :
 Vat Dyes
 Sulphur Dyes

55 | P a g e
5.5.1 Vat Dyes :
The name vat was derived from the large wooden vessel from which vat dyes were first
applied. Vat dyes provide textile materials with the best colour fastness of all the dyes in
common use. The fibres most readily coloured with vat dyes are the natural and man-made
cellulosic fibres. Vat dyes are more expensive and difficult to apply than other classes for
cellulose such as directs, sulphurs, and reactive. Indigo is a special case in the vat dye class.
Indigo is attractive for its pleasing blue colour and for the unique fading characteristics of
garment dyed with it. Vat dyes are characterized by the presence of a keto group. Vat dyes
in keto form are water insoluble pigments.
5.5.1.1 Why So Called Vat Dye?
The word vat means, ‘Vessel’. The dyes take their name from vatting. The vat dyes are
naturally coloring matter and kept in wooden vat and make solubilise vat dyes by the
process of formantation – so it is called vat dyes. They are applied in a special kind of a dye
bath in which the dye is reduced to a soluble form by means of a strong reducing agent,
such as hydrosulphite. The vat dyes are insoluble and cannot be used directly and requires
vatting. Among all the dyes, it has the best fastness properties.
5.5.1.2 Dyeing with vat dyes :
The application of vat dyes to cellulosic materials occurs in five stages.
Aqueous Dispersion:
The insoluble vat dye is dispersed in water.
Vatting:
This step involves the chemical reduction of the vat dye to produce the soluble, reduced or
leuco form of the dye. This is achieved by Sodium Hydro sulphite, Sodium Hydroxide and
water. The sodium hydrosulphite chemically reduces the vat dye in the alkaline conditions
created by the presence of sodium hydroxide.

56 | P a g e
Absorption of dye molecules by the fibre :
The vatted dye molecules are substantive to the cellulosic material when this is introduced
into the dye liquor. To achieve adequate exhaustion, an electrolyte is added to the dye
liquor and the temperature may be increased depending on the specific vat dye. The
application of the dye molecule to the fibre occurs at temperatures specific to a particular
vat dye and occurs in a range from 200 C to 600 C. The addition of the electrolyte alters the
equilibrium of the dye liquor so as to increase the substantivity of the dye molecules for the
fibre. During this stage of dye application the textile material must be kept immersed in the
dye liquor to prevent premature oxidation of the leuco compound.
Figure: Water soluble leuco form of indigo
Re-oxidation of dye molecules within the fibre:
Once within the polymer system of the fibre the leuco form of the vat dye has to be oxidized
and converted to its original colour and the insoluble form of the dye. Oxidation of the leuco
compound can be achieved by atmospheric oxygen although this is somewhat slow. In
practice, a mild oxidizing reagent such as sodium per borate is used to convert the soluble
leuco compound into the original insoluble vat dye.
Soaping-off vat dyes:
During the previous stage some insoluble vat dye may be deposited on the surface of the
textile material. This has to be removed to prevent poor rub-fastness as well as a possible
change of shade due to the subsequent removal of this surface deposit. Soaping-off, which

57 | P a g e
is the boiling of the dyed material in a liquor containing some suitable detergent, removes
this surface dye. The term soaping-off was derived from the fact that before the
development of detergents, soap was used to remove the surface dye.
5.5.2 Sulphur Dyes :
These dyes are so called because they contain sulphur atoms in their molecules. The fibres
most readily coloured with sulphur dyes are the natural and man-made cellulosic fibres.
5.5.2.1 Chemistry of dyeing with Sulpher Dye :
The Sulpher dyes contain Sulpher linkage within their molecules. They are insoluble in
water but can be made soluble in water by treating them with reducing agents. This also
makes them substantive towards cellulosic fibres. Na2S acts as reducing agent that breaks
the Sulpher linkage and break down the longer molecules in to simple components which
can penetrate the material (fiber/fabric) surface easily.
5.5.2.2 Dyeing with Sulphur Dyes :
Initially the goods are wet out in the bath. Since the dyeing liquor contains appreciable
amounts of sulphide, copper fittings must be avoided. If wetting or penetrating agents are
used these should be of the anionic type since non-ionic surfactants form stable, non-
substantive complexes with the leuco thiols. An anionic product such as phosphated 2-
ethylhexanol is suitable. The bath may then be set at 40°C with some sodium polysulphide.
Polysulphides in the leuco dyebath prevent premature oxidation of the dye and reduce the
tendency to bronziness of deep dyeing of blues, navies and blacks. An addition of a

58 | P a g e
sequestrant such as EDTA avoids precipitation of the leuco thiolate by calcium and
magnesium ions. The leuco dye is then added slowly and, since the leuco dyes only have low
to moderate substantivity for cellulose, some salt may be added initially, or in portions
during dyeing, to promote exhaustion. After dyeing the goods are rinsed, the leuco dye
oxidised and the dyeing is soaped as for a conventional vat dye.
Sulphur dyes usually have acceptable substantivity, particularly in the presence of salts, so
that stripping in a fresh reducing bath is not easy. Dyeing is often conducted at the boil but
this decreases the degree of exhaustion. Sulphur dyes require less salt than reactive dyes
and usually have reasonable exhaustion. Low sulphide leuco dyes require more salt and no
polysulphide. They do not give good exhaustion in heavy shades and the use of a low liquor
ratio is recommended. For popular shades such as black, it has long been common practice
to use a standing bath. This is a dye bath that is re-used for subsequent dyeings after
addition of more reduced dye. Any free sulphur that tends to accumulate is dissolved by
addition of sodium sulphite to give thiosulphate. This prevents it sticking to the goods. The
actual dyeing temperature can vary. At higher temperatures around the boil, the bath
exhaustion is less but penetration of the leuco dye into the fibres is better than at lower
temperatures.
5.6 Denim Dyeing Process :
There are three processes in the practice for continuous denim dyeing:
1. Rope Dyeing
2. Slasher or Sheet Dyeing
3. Loop Dyeing

59 | P a g e
5.7 Rope Dyeing :
The indigo Rope dyeing technology for denim production is considered a superior dyeing
technology, where better uniformity of dyeing is achieved than other Indigo dyeing
technologies like slasher dyeing. Indigo rope dyeing was started in USA.
Today rope dyeing accounts for a large percentage of warp yarn dyed for denim production.
The system offers highest production, due to continuous process, as there is no stoppages
for set changes. In this dyeing method, maximum continuity of shades and minimum danger
of center to selvedge shade variation can be achieved. Flow diagram of rope dyeing is shown
in Fig. . During dyeing process, it forms a coating in the outer layers of the cotton yarn and
fiber. This produces a ring of color around the cotton yarn, with the core remains white core.
This dyeing effect is known as ring dyeing.
Fig. : Rope dyeing and subsequent sizing, Step 1: Ball Warper, Step 2:Rope Dyeing, Step 3: Long Chain
Beamer, Step 4: Sizing
Indigo dye is a vat dyestuff. It is insoluble in water and has a very poor affinity to cellulose
fibers like cotton fiber. In normal stage, indigo will not dye cotton fiber. For dyeing of cotton
yarn, indigo should be converted into water-soluble “leuco” form in chemical reduction

60 | P a g e
process. Reducing agents such as sodium hydrosulfite with sodium hydroxide are used to
convert the indigo dye to its soluble form. The reducing agent also initially changes the color
of the dye from its blue color to a very pale greenish yellow color. The leuco form of indigo
forms a coating on the outer layer of the cotton yarn. The yarn is then exposed to the air,
where the indigo become insoluble by oxidation. The oxygen in air converts the soluble
indigo dye to its original insoluble form and back to its original blue color. The chemical
reaction is shown in Fig. .
Fig. : Simplified description of the reduction/oxidation of Indigo
When the indigo dye oxidized, it becomes trapped into the outer layers of the cotton yarn.
In a single passage of indigo dye, a small amount of dye being deposited on the yarn surface
which causes light blue shade. In order to obtain deep indigo blue shades, the cotton yarn
should be subjected to repeatedly dye with indigo dye. The indigo dye is layered by dyeing
in a multiple passes of the rope into the soluble indigo dye and then subsequently exposing
it to the oxygen in the air for oxidation. This multiple passing of yarn into dye bath is known
as dipping. Normally, the cotton yarns are dyed with indigo dye in at least 4 to 8 passages
of the dye bath. After every passage of dye bath the yarns are exposed to air and followed
by further dipping in soluble indigo dye bath. After every passage of the dye bath all the
oxidized indigo dyestuff fixed on the surface of the cotton fiber/ yarn, only a small portion
of indigo is replaced by fresh indigo. This results in the increase in the depth of shades.

61 | P a g e
In some cases a sulfur black or blue dye can be applied to the yarn before indigo dyeing in
order to achieve darker shades. This is known as a sulfur bottom. If the sulfur dye is applied
after the yarn has been indigo dyed, it is known as sulfur top.
5.8 Process sequence in Indigo rope dyeing in denim :
In rope dyeing, 12-36 ball warping ropes of yarn are fed side-by-side simultaneously into
the rope dyeing range for application of the indigo dyeing. The process sequence is as
below:
Fig. : The passage of yarn in rope dyeing
Pre-scouring
In the rope dyeing range the ropes are first passed through one or more scouring baths. It
consist of wetting agents, detergents and caustic. The objectives of pre-scouring is to
remove the wax content from cotton, naturally occurring impurities in cotton fiber yarn such
as dirt, minerals, ash, pectin, and naturally occurring waxes, removal of trapped air from
cotton yarns through wetting the yarn at temperature of 90 to 95ºC. Removal of these
materials is very important in order to achieve uniform wetting and uniform dyeing. The
trapped air is essential to be removed as it may cause uneven dyeing. There is approx. 2
liters of air in 1 kg of yarn. One liter of air decomposes 2 liters of Sodium hydroxide which
also increase consumption of sodium hydroxide.
The following agents normally used in pre-scouring.
 Caustic Soda: In pre-scouring, 3–5% sodium hydroxide (depends upon

62 | P a g e
the quantity of cotton fibers) is used, which removes the wax by the action
of soapanification.
 Wetting agent: Anionic wetting agent are normally used.
 Sequestering agent: It is used to make the water soft, as it is very
difficult to find the desired softness in water (about 1-3 ppm) even with the
use of soft water.
The ropes are subsequently fed into one or more water rinsing baths.
Hot wash
The ropes is hot washed 80 – 90ºC to remove the sodium hydroxide left in the yarn after
pre-scouring, otherwise it will change the pH values of dye – bath.
Cold wash
After hot wash, the yarn ropes is fed through a cold wash bath to brought back to its room
temperature.
Dyeing
The ropes of yarn are then fed into the indigo dye baths and skyed after each dip. As the
constant of substantivty for indigo it is only 2.7, where as for other color, it is 3.0. Hence
there is a need of repeated dipping of 5 to 6 dye baths with multi – dip and multi –nip facility
to increase the penetration.
As indigo belongs to IK class of vat dyes, the dyeing is done on room temperature, and
oxidation is done by air. Sodium hydrosulphide is used to reduce the indigo, as Indigo is not
soluble in water. Then caustic soda is also used to make sodium salt of vat color to make it
soluble.
The pH of the indigo dye bath should be maintained between 10.5 to 11.5, as at this level,
the dye affinity is very high. This is because at this pH, sodium salt of indigo is mono phenolic
form. pH is maintained by the addition of caustic soda.

63 | P a g e
Washing
After the dyeing process, the ropes of yarn are rinsed in several water baths to remove any
unfixed dye. Rubbing fastness of indigo, which is a very important parameter, can be
improved through washing. In a typical indigo dyeing range, there are four wash bath after
the dye bath. The typical washing process are in Fig.
Fig. : Typical washing Process
The softener treatment at the last was box is very important in rope dyeing. The dyed rope
is to be opened at the next operation, Long Chain Beamer. The softener helps easy opening
of the rope, hence less end breakages.
Cationic softener is generally used with 1.2% of the weight of the yarn and pH in the range
of 4 to 5.5. Softening treatment is done at room temperature, as high temperature may
cause tendering of yarn.
Drying and Coiling
After the washing, the ropes are dried by hot cylinder and coiled incan.
Fig. : Rope cans

64 | P a g e
5.9 Process Control of indigo rope dyeing
Concentration of Hydrosulphite
Hydrosulphite is measured by vatometer. It should be from 1.5 gpl to 2.5gpl. It can also be
measured by Redox potential of dye bath which should be from -730 mV to -860 mV.
Relatively high conc. of hydrosulphite gives a clear shades with minimum reddish streaks.
The indigo dye stuff in the dye bath should be kept in soluble stage. Indigo dye has a
tendency to react with the oxygen in the air and get oxidized and transferred into their
original insoluble stage. Hence an extra quantity of hydrosulphite is maintained in the dye
bath to keep the indigo dyestuff in soluble stage.With lack of hydrosulphite, the leuco indigo
is less dissolved and goes to insoluble stage and thereby adheres to a greater extent to the
fibers. Further lack of hydrosulphite may cause higher unreduced dyestuff in the liquor. This
results unfixed dyestuff onto the yarn. Under these circumstances a reddish bronze like
shade is developed in the yarn.
Caustic Soda or pH value
The pH of the dye bath should be around 10.5 - 11.5, as at this pH range, there will be
formation of more monophenolate ions, which lead to higher color yield and good wash
down effect. At higher pH, dye penetration is less and leads to poor wash down effect.
The pH influence the shades in the following way:
High pH or Caustic Concentration --> Redder and lighter
Low pH or caustic concentration --> greener and darker
Dye concentration in Dye bath
Dye concentration is an important parameter in indigo dyeing. Generally the concentration
of dye influence the shades as below:
High Indigo Concentration --> Shade is greener and lighter
Low Indigo Concentration --> Shade is dull and Red.
Dipping Time
The dipping time of the ropes in the dye bath plays an important role in indigo dyeing.
Dipping time varies from 15-22 seconds. Longer the dipping time, better will be the
penetration. However, too long dipping time may dissolve the previously oxidized indigo. At

65 | P a g e
very short dipping time, the liquor exchange, i.e. the amount of chemicals consumed and
replaced by fresh addition of reduced indigo, will not be adequate. This may leads to poor
dyeing and depth of dye penetration. However the time available for diffusion of dyestuff
until oxidation commences is too short.
Squeeze Pressure
The squeezing pressure should be optimum. High squeezing pressure may leads to low pick
up of color and better penetration. At rope dyeing, squeeze pressure may be between 5-10
tones. Squeeze roller hardness should be about 70-75 deg. shores
Airing Time
Airing time is an important consideration in rope dyeing for proper oxidation. The airing
time should be 60- 75 seconds. Longer airing time leads to high tension on the yarn, whereas
low airing time leads to poor oxidation.
Drying
The dyed and washed rope should be properly dried with proper moister content.
Insufficient or uneven, over or less dried yarns will result in poor opening and high
end breakages in re-beaming.

66 | P a g e
5.10 Slasher Dyeing :
In continuous slasher/sheet dyeing and sizing machine, direct warping beams are used,
instead of ball warping logs in case of Indigo rope dyeing system. The Slasher Dyeing
machine is capable of handling Ne count form 9/s to 30/s (OE and Slub both). Typical
schematic sheet dyeing range is shown in Figure. At the back end of the slasher/sheet dyeing
range, the direct warping beams are creeled. The yarns sheet from each beam is pulled over
and combined with the yarns from the other beams so that multiple sheets of yarns can be
made. When dyeing according to the sheet dyeing method, instead of cables the warp
threads are fed to the machine parallel next to each other. These are much smaller
compared to the rope dyeing machines. Another advantage is that the cables don’t need to
be open after dyeing.
Moreover, each yarn wets much faster and in this way reduces the dipping and wetting
times during dyeing. All in all, each thread has a larger surface compared to a dyeing cable
and this requires somewhat more hydrosulphite to prevent a premature oxidation of the
indigo.
Figure: Sheet Dyeing Range

67 | P a g e
5.11 Loop Dyeing :
In the loop dyeing process, the yarn is dyed in a single bath instead of several. The desired
depth of color is attained by passing the yarn through the vat several times. Subsequently,
as a part of the same process, the yarn is sized. The advantages and disadvantages of loop
dyeing are the same as with sheet dyeing.
Figure : Loop Dyeing
5.12 Difference between Slasher and Rope Dyeing :
Comparison On Slasher Dyeing Rope Dyeing
Required Space Less More
Mercerizing Easy Difficult
Manpower Less More
Dye bath Less capacity More
Broken end repairing Not Possible
In rope dyeing there is
apossibility to repair broken end
in LCB(Long ChainBeamer)
Flexibility Flexibility to produce denim in different
colors and small quantities
Less flexible. Difficult to change
colors.
Set change
Machines should start and stop at the
time of set change. Hence shade
matching is not easier until hundreds of
meters of yarn run.
No need to start and stop the
machine at the time of set
change. Hence shade matching is
easier.
Extra ends Extra ends Required. No extra ends.
Different colour mixing Not possible
Possible to mix ends of different
colours. One can get stripe
design at re-beaming.

68 | P a g e
Count range Advantages for lighter yarn. Can use Ne
1-30 without major change.
Large numbers of yarns are
difficult to open at re-beaming.
Hence it is not suitable for fine
yarn. CanuseNe1-16 without
major change. In latest machines
even higher yarn count can
bedyed.Rear view characteristics
offabric
Less thin / thick & knot points High thin / thick & knot points
Dye dipping time for
effective dye result
< = 14s ( standard 10 – 14sregulated by
speed)
< = 21s ( standard 15 –21s
regulated by speed)
Production capacity
Approx. 9 to 11 mill. Mt. in case of
normal capacity. Approx. 10 to22 mill.
Mt. in case of double capacity.
12 ropes = 9 to 11.5 mill. Mt.,
24 ropes = 18 to 23 mill. Mt.,
36 ropes = 27 to 34.5 mill.Mt.Cost Cost of production is lesser compared
to RopeDyeing
Cost of production is more
compared to sheetDyeing
5.13 Relative merits and demerits :
 Generally rope dyeing denim range produces better quality of denim than slasher
dyeing.
 Rope dyeing means for higher production and long runs. Ropes dyeing can more lots
without any stoppages at set change. In case of sheet dyeing, the machine remains
stop at set change.
 In rope dyeing better dry and wet fastness properties in denim fabric can be
achieved, than sheet dyeing.
 In sheet dyeing good quality yarn is required, as mending of broken ends is very
difficult in sheet dyeing. This problem is less in rope dyeing.
 Sheet dyeing produces more waste than rope dyeing.
 Lot to lot, set to set shade consistency is better in rope dyeing,
 In sheet dyeing, there is a problem of center to selvedge shade variation. This can be
caused due to uneven nip pressure, non-uniform chemical and colour content in dye
boxes. This problem can also occur in rope dyeing as well. But proper rotation of the
dried yarn cans at spreading and winding and even distribution of warp yarns over
the full width of the fabric minimize the problem.
 The wetting and immersion time, oxidation time of dyed yarn are less in sheet dyeing
due to parallel warp threads.

69 | P a g e
5.14 Dyeing in Amber Denim Mills Ltd. :
5.14.1 Machine Specification :
Brand name Morrision Rope Dyeing
Model Nill
Year of construction 2012
Country of origin American
Creel capacity 37
Speed 30-35 m/min
Number of dye bath 8
Total no of box 15
No of dry cylinder 36
Year of construction 2012
Air Pressure required 5.4(Depend on Count)
Steam pressure required 5kg

70 | P a g e
Dry Cylinder Temp. 1st
5 bar-2nd
2.3 bar
production/day 70000 m/day
5.14.2 Dyeing :
There are several types of dyeing available in denim. But in Bangladesh 4(four) types of
dyeing processes are used:
 Pure Indigo
 Topping or Indigo Bottoming Sulphur Topping (IBST)
 Bottoming or Sulphur Bottoming Indigo Topping (SBIT)
 Pure Black/Sulphur
5.14.3 Pure Indigo :
Indigo dye is an important dyestuff with a distinctive blue color (see indigo). The natural dye
comes from several species of plant, but nearly all indigo produced today is synthetic.
Among other uses, it is used in the production of denim cloth for blue jeans. The form of
indigo used in food is called "indigotine", and is listed as FD&C Blue No. 2.
Flowchart for Pure Indigo:-
Creeling

Scouring/Mercerizing

Cold Washing Bath

Cold Washing Bath

Indigo Color Bath-1

71 | P a g e

Oxidation

Indigo Color Bath-2

Oxidation

Indigo Color Bath-3

Oxidation

Indigo Color Bath-4

Oxidation

Indigo Color Bath-5

Oxidation

Indigo Color Bath-6

Oxidation

Indigo Color Bath-7

Oxidation

Indigo Color Bath-8

Hot Washing Bath-1

72 | P a g e

Hot Washing Bath -2

Hot Washing Bath -3

Softener

Dryer

Can
5.14.4 Topping :-
In this method two type dyes are used for developing the required shed. In the topping
method the Indigo dyes are used to develop the blue in the bottom part of the yarn whereas
the Sulphur dyes are used to develop the black color shed in the top part of the yarn.
Flowchart for Topping:
Creeling

Scouring/Mercerizing

Cold Washing Bath

Cold Washing Bath

Indigo Color Bath-1

Oxidation

Indigo Color Bath-2

73 | P a g e

Oxidation

Indigo Color Bath-3

Oxidation

Indigo Color Bath-4

Oxidation

Indigo Color Bath-5 (Off)

Oxidation

Indigo Color Bath-6 (Off)

Oxidation

Normal Wash Bath-7

Oxidation (Nill)

Black Color Bath-8

Hot Washing Bath-1

Hot Washing Bath -2

Hot Washing Bath -3

74 | P a g e

Softener

Dryer

Can
5.14.5 Bottoming :-
In this method two type dyes are used for developing the required shed. Here Sulphur dyes
are used to develop the black color shed in the bottom part of the yarn whereas the Indigo
dyes used to develop the blue in the top part of the yarn.
Flowchart for Bottoming:
Creeling

Scouring/Mercerizing (Off)

Cold Washing Bath

Cold Washing Bath

Black Color Bath-1

Oxidation

Normal Wash Bath-2

Oxidation (Nill)


75 | P a g e
Normal Wash Bath-3

Oxidation (Nill)

Indigo Color Bath-4

Oxidation

Indigo Color Bath-5

Oxidation

Indigo Color Bath-6

Oxidation

Indigo Color Bath-7

Oxidation

Black Color Bath-8

Hot Washing Bath-1

Hot Washing Bath -2

Hot Washing Bath -3

Softener


76 | P a g e
Dryer

Can
5.14.6 Regular Dyeing Recipe :
Recipe for Indigo
Indigo 100 gpl
Coustic 75 gpl
RD-999 6 gpl
Hydro 100 gpl
Lediquest 6 gpl
Total Volume 3000 L
Recipe for Botoming
Sulfotex 30 gpl
Coustic 15 gpl
RD-999 6 gpl
Secho 2 gpl
Reducing Agent 10 gpl
Total Volume 2700 L
Recipe for Topping
Sulfotex 60 gpl
Coustic 61 gpl
RD-999 5 gpl
Reducing Agent 25 gpl

77 | P a g e
Total Volume 600 L
Recipe for Scouring
Secho 2 gpl
Coustic 30gpl
RD-999 6 gpl
Total Volume 2700 L
Recipe for Scouring
Softener 14 gpl
Total Volume 1700 L

78 | P a g e
5.14.7 Equipments used in dyeing lab :

79 | P a g e
Chapter Six
Long Chain Beaming

80 | P a g e
6.1 Long Chain Beamer :
After the rope dyeing of warp yarn in denim production, the next operation is the Long Chain
Beamer (LCB). When the rope has been dyed and dried in the rope dyeing range, it is taken
in large cans in coiler section. In rope dyeing range, if the machine has a capacity 24 ropes,
then there will be 24 separate coilers which delivers 24 ropes in separate cans. These cans
are transferred to the Long Chain Beaming area. The basic purpose of long chain beamer is
to open the rope into a sheet form of yarn and wind onto a warper beam which in turn
transferred to the sizing machine.
In Long Chain Beamer, the yarn alignment in the dyed rope is change from a rope form to a
sheet form. In the Long Chain Beamer the rope pull from the can ( Fig. 2) by moving them
upward to a guiding device. The guiding device is mounted above the can, probably in the
ceiling. The upward movement of the rope allows the ropes to untangle before nearing the
beamer head and allow the rope to shake loose form from the rest of the rope in the can.

81 | P a g e
6.2 Process Flowchart For Long Chain Beamer :
Can

Accumulator

Tension Stand

Tension Control Dancer

Reed

Counting Roller

Beam

Industrial training on amber denim mills limited

Industrial training on amber denim mills limited

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Industrial training on amber denim mills limited

Similar to Industrial training on amber denim mills limited (20)

Recently uploaded

Recently uploaded (20)

Industrial training on amber denim mills limited