2013

NED UNIVERSITY OF ENGINEERING AND

TECHNOLOGY (STUDENTS)

RAJBY DENIM

12/31/2013

REPORT

ACKNOWLEDGEMENTS

In the name of Allah, the most merciful and beneficent All praise to Almighty Allah, the most Gracious and compassionate. Who created the universe and bestowed mankind with the knowledge and blessings of Allah be upon the Holy Prophet Muhammad (S.A.W.) who guided mankind with the Holy Quran and Sunnah, the everlasting source of guidance and knowledge for humanity.

Firstly, all we are very thankful to the Director of RAJBY DENIM MR. husSAM sb and General Manger .. Then we are deem it an utmost pleasure to be able to express to heartiest gratitude and deep sense of devotion to my reverend and worthy Supervisor Mr. Ishtiaq and Mr. Saqib (Dyeing section) for his skill ful guidance, unfailing patience, inspiring attitude and invaluable suggestions to improve the script of this report. A deep sense of appreciation is owed to Mr. Shahnawaz for his kind attitude and keen interest during my internship. I am also thankful to Mr. Ikram who helpsme during my internship in Rebeaming/Sizing department. I am also thankful to all the workers of weaving department specially Mr. Khalid Umer (Manger)who provide me a valuable guidance during my internship program. I fervently extend my thanks to Rashid sb in Inspection/Dispatch ,Sohail sb , Shakeel sb in R&D LAB/ WASHING department and special thanks to the manger of the utilities Asad sb and Qurban sb (Manger) of ETP plant . I am also tahnkfull to Iowed a debt of gratitude to my ever-affectionate brothers Mr. ZUBAIR ALAM AND our Nedian Syed Rehan Shukat for their fragrant love nominated to me and my group members .Last but not least I offer my humble heartfelt gratitude and deepest affections to my greatmother and respected father for being inspired for higher ideals of life, supported morallyand financially throughout my studies, and always prayed for glorious success about me.

PROCESS STAGE OF DENIM AND MACHINE (AT RAJBY)

DEPARTMENT CONCERN PERSON

YARN GODOWN/ BALL WARPING RIAZ SB/UMER SB

ROPE DYEING SHAHNAWAZ SB/ISHTIAQ SB

REBEAMER/SIZING IKRAM SB

WEAVING KHALID SB

FINSHING ZAFAR SB/RASHID SB

INSPECTION/DISPATCH RASHID SB

R&D LAB/ WASHING SOHAIL SB/ SHAKEEL SB

POWER HOUSE/BOILER/RO PLANT

ASAD SB/ ALEEM/ WASEEM

COMPRESSOR/CHILLER/RECO ASAD SB/YASEEN

WORKSHOP/ETP ZUBAIR SB/QURBAN SB

THE ALL CONCERN PERSONS AND WORKER OF RAJBY TEXTILES REALLY

HELPED US FOR UNDERSTANDING THE PROCESS AND MACHINES.

UNIT OF RAJBY DENIM

UNIT :1 YARN GODOWN

UNIT:2 BALL WARPING SECTION

UNIT:3 ROPE DYING SECTION

UNIT 4: RE-BEAMEING SECTION

UNIT:5 SIZING

UNIT:6 WEAVING

UNIT:7 FINSHING

SUB. UNITS:

1) SINGEING

2) MERCERIZING

3) PAD STEAM / OVER DYE

4) SUNFORIZING

UNIT:8 INSPACTION & DISPATCH

UNIT:9 R &D LAB / WASHING

UNIT:10 MILL UTILITIES

DENIM HISTROY & INTRODUCTION OF DENIM:

The term "Denim" has originated from the city of Nimes in France where " serge de Nimes" was manufactured . Denim fabric is dyed by Vat or Indigo dye, which is applied to cotton fabric in loosely held form in layers. In manufacturing process of denim , it is similar to that of Grey fabric up to the process of weaving with the only difference that in case of Denim fabric, it is dyed at the stage of sizing where as in case of Grey fabric, the decision regarding dyeing stage depends upon the finished product. Generally, denim fabric are 3/1 warp- faced twill fabric made from a yarn dyed warp & an undyed weft yarn . Normally dyed & grey ring or open- end yarns are used in warp & weft respectively. Traditionally speaking, the warp yarn is indigo dyed . Now a days Indigo, Sulphur black, Blue black(dyed both in black & indigo color) & various Colored denim in both stretch & nonstretch form are widely used worldwide . Denim is a very versatile fabric, and is very popular for a variety of shade,looking & hand feel on same fabric for different types of wash . Actually wash is known as ornament for Denim fabric.

DENIM FABRIC

INTRODUCTION OF DENIM

PROCESS FLOW FOR DENIM MANUFACTURING:

The following flow chart reveals the necessary steps in the manufacture of denim fabrics. beginning with the production of the warp yarns used. The chart forms an outline for most of the topics that will be covered in this bulletin.. THESE 3 DIFFERENT PROCESS USED IN DIFFERENT DENIM INDUSTRIES

Process Flow for Warp Yarn in Denim Manufacturing

Common Yarn Sizes for Denim:

Warp yarns for bottom weight jeans typically range in size from Ne 4.0 to Ne 12.5/1. Finer yarns are used for lighter weight chambray shirting fabrics and lighter weight jeans, vests, dresses, and skirts. These yarns may range in count from Ne 12.5 to Ne 30.0.

Yarn Spinning Systems:

All denim yarns were ring spun. Today, denim fabrics have different combinations of ring and open-end yarns. When you hear a term such as ring/ring, open end /open end (OE/OE), and ring/OE, it is referring to which yarn is in the warp and which yarn is in the filling, respectively. For example, ring/OE indicates a ring-spun warp yarn and an open-end filling yarn. Weaving a combination of ring-spun and open-end yarns can help to reduce fabric costs while still maintaining some favorable ring-spun fabric characteristics..

Specialty of Yarns:

Structured Denim 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..

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 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 (SPECIALITY: STRECH ABLE)

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 .. thats the speciality of lycra yarn.

BALL WARPING INTRODUCTION: WARPING:

Warping is the process of transferring multiple yarns from individual yarn packages onto a single package assembly.

TYPES OF WARPING USED IN THE DENIUM INDUSTRIES:

High Speed Warping (Direct Warping). Sectional Warping (Indirect Warping). Ball Warping (Used for Denim Fabrics). Draw Warping (Heat Set).

BALL WARPING (PROCESS):

In ball warping 250 to 480 yarn ends are pulled from the creel. The yarns then pass through a comb-like device (sometimes called a hack or reed), which keeps each warp yarn separate and parallel to its neighboring ends. At intervals of every 1000 or 2000 yards (or meters), a lease string is placed across the sheet of warp yarns to aid yarn separation for the re-beaming operation, which will occur later. The yarns then go through a funnel-shaped device called a trumpet or condenser, which collapses and condenses the sheet of yarn into rope form. This device is located at the base of the warper head and traverses back and forth, guiding the newly formed rope of yarn onto a log.

BALL WARPING

FURTHER, The rope must be wound at a constant tension to keep the yarns from tangaled *The ball warping process is depend upon the weight of the cone Weighing of cone are,. *4.16 lbs *6.25lbs *8.33lbs

MACHINE SPECIFICATION: KARL MAYER (GERMAN TECHANOLOGY)

PART OF BALL WARPING MACHINE:

CREEL It holds yarns cones. The creeling arrangement used in RAJBY DENIM is H-shaped creel and V-shaped creel. *H-SAHPED CREEL

*V-SHAPED CREEL

BALLON CONTROL RING

TENSION DISC: Tension is applied from above- there are weights or spring loaded.A gear under each pair of disks is matched to another gear mounted on a continuous shaft whichruns the length of the vertical tension post.

CERAMIC GUIDE :

*DANCER :

TRAVERSE

LOG: For ball warp denim, the yarns are brought together and condensed into a rope before being wound onto a relatively short cylindrical barrel (sometimes called the shell or log) that has no end flanges.

CONTROL PANEL

Through the control panel the variation of speed and the panel are controlled through the control panel.

ROPE DYING (MANAGER: SHAHNAW SB)

INTRODUCTION

ROPE DYING:

The Rope dying is the process in which the single warped or weft yarn is to be dyed.. The best possible indigo dyeing method for yarn, the threads of denim yarn are initially twisted into a rope, then undergo a repetitive sequence of dipping and oxidization. The more frequent the dipping and oxidizing, the stronger the indigo shade Indigo dying method is not only the process for coating dying on to the yarn segment. Sulphur dyes, Bottoming ( process), Topping (process) are the process for dying the yarn segments (Its depend on the requirement of the shade) Its Consists of twisting the yarns into a rope that is then quickly dipped into indigo baths. It is considered the best method for dyeing denim as the short dyeing time does not allow the indigo to fully penetrate the fibers

Rope Dying Machine

Machine: ROPE TEX (JMT DENIUM)

ROPE TEX: (JMT DENIUM) IS THE ITALIAN TECHANOLOGY

MACHINE USED TO DYE THE ROPE..

ROPE DYING MECHINE (JMT ROPE TEX)

HYDROLIC PRESSURE PUMPS

(APPLIED PRESSURE FOR MANTAIN THE PRESSURE ON THE ROLLERS

During the process)

PROCESS: THE 24 LOTS are process in the machine at a time and 1400 m yarn are processing in the machine. The 5 Different shades should be processing in the machine . With the variation of colours.

1) BOTTOMING

2) TOPPING

3) PURE INDIGO

4) GREY

5) SANDWICH

SANDWICH: Sandwich is the shade from the combination of bottoming and the topping.. the variation of the

shades in the sandwich but it depend upon the requirement of output.

(All the categories and chemical process remain same as in bottoming

and topping)

SULPHER DYES

BOTTOMING:

For making the shades the bottoming is the first process in the rope dying process. BOTTOMING the coating of sulphur at 85 degree C ( Note: the temp should be maintain during this process, if variation of temp will effect the colour ) and then it dipped into the indigo dyes, after it transfers into the steam chamber, due to the steam the fixation of dyes or shade is possible .Then It passes through the washing chambers by washing the extra dyes should be bleed out, and transfers to the next stages. ( Note: This process is not for the pure indigo (shades) )

TOPPING: The Topping is the process for coating the indigo dye with the fixing agent hydra. (REDUCING AGENT) After itll be coated with the sulphur. This can be proceeds in the last stages of the process. (Note: the process steps will be the same as for bottoming, just for swaping of indigo with sulphur)

Sulphur rope dyeing in Denim The technical features of dyeing of sulphur dye are given as follows. 1st wash tank Caustisizing by taking 25 % Caustic soda. 2nd wash tank Hot wash at 70-80C. 3rd wash tank Cold wash at 30C.

RECIPY AND PROCESS OF MAKING THE SULPHER DYES AND SHADES:

a. Solubalised sulphur dye = 150 g/l. b. Sodium sulphide (reducing agent) is added to increase its reducing power. c. Sodium hydroxide = 10 12 g/l. d. Wetting agent = 3 4 g/l. e. Antioxidant sulphide (Glucose solution= 4-5 g/l), which is added to preventthe oxidation of sulphide solution. f. In third, fourth and fifth dye bath is cold wash.

INDIGO DYES

(PROCESS, SHADES, RECIPY)

INDIGO DYES: Indigo dyes are usually known as the anthraquinone dyes. Its one of the oldest dye in the world. Indigo dyes are used in the denim industry , it the basic dyes in variation the colour & shades.

Process: The process for the making of the shades, first the yarn is dipped in the solution of NAOH caustic soda (caustic soda+water) this gives the fixation of the dyes.

PASSING OF ROPE FROM THE CAUSTIC(REDUCING AGENT)

AT RAJBY

PROCESS:

Indigo Dyeing

1. Indigo is not a perfect vat color. It may be called a trash vat color. The constant of substantivty for other color is 3.0, for indigo it is only 2.7, so there is a need of 5 to 6 dye baths and make the use of multi dip and multi nip facility to increase the penetration. 2. The dyeing is done on room temperature as indigo belongs to IK class of vat dyes, where dyeing is done at room temperature and oxidation is done by air only and not by chemicals, if oxidizing agent are used, they will cause stripping of colors. 3. Indigo is not soluble in water, so it is reduced with sodium hydrosulphide. Then caustic soda is added to make sodium salt of vat color to make it sol.

Indigo Rope Dyeing in Denim

a) The passage of yarns in rope dyeing is pre-scouring b) hot wash c) Cold wash d) Dye bath Hot wash e) Application of softener (Cationic).

RECIPY OF MAKING INDIGO DYES:

3000 LITRE (WATER)

INDIGO (POWDER FORM)

CAUSTIC SODA

LUNIEL AGENT (FOR REDUCING THE FOAM)

Hot wash: As some sodium hydroxide is carried by the yarn after pre-scouring, hence a hot water wash is given at 80 90C. If this is not done, yarn which will go into the dye-bath will change the pH values of dye bath..

Cold wash: After hot wash, high yarn temperature is brought back to its room temperature, with the help of cold wash applied to the ROPE.

COATING OF INDIGO DYE (AT RUJBY)

3000 LITRE TANK CAUSTIC IN THE TANK (AT RAJBY)

Changing of shade due to processing

PROCCESING REPORT

RE-BEAMING Once the warp yarns are rope dyed, it is then necessary to change the yarn alignment from a rope

form to a sheet form before entering the next process, which is slashing or sizing. Beaming or re-

beaming involves pulling the ropes of yarn out of storage tubs and moving them upward to a

guiding device (sometimes called a satellite).

This upward travel allows the ropes to untangle before nearing the beamer head. Once the ropes

come down from the guiding device, they go through tensioning rollers to help further the

separation of the ropes before going through a comb at the warper, which separates individual yarn

ends and keeps them parallel to one another. From the comb, the warp yarns are guided onto a

flanged section beam. Multiple warp section beams are made forming a set of beams, which will be

the yarn supply for the slashing operation. Each set normally contains 8 to 14 section beams. At this

point, there should be no crossed, lost, or tangled ends on the beams.

RE-BEAMING MACHINE: KARL MAYER

The total number of yarns on all the beams in the set should meet specifications for the given fabric

to be woven. The beams need to be in good condition with smooth inside flanges, to be non-

eccentric barrels, and to contain no high or low selvages. The selvage is the edge of the yarn sheet

where it touches the beam flange at each end of the beam. It is critical that all the yarns wound

onto a given section beam be under equal tension. This is maintained by using guides, tension

devices, and stop motion controls.

Sizing Section

(Manager: IKRAM SB)

MACHINE : KARL MAYER (GERMAN TECHANOLOGY)

(12 CREEL ARANGMENT AND MACHINE OF SIZING) MANUFACTURER : KARL MAYER

SIZING: Natural starch and its derivatives still constitute nearly 75%of the sizing agents used in the textile industry throughout the world.. the amount of starch applied to staple yarn varies anywhere up to 15% of the weight of the yarn. The introduction of the new types of polymer synthetic sizing materials such as polyacrylates, polyesters, and polyvinyl alcohols (PVAs) has helped to reduce the amount of coating requiredCMC sizes are combined with PVA or acrylic Carboxymethyl cellulose (CMC)are used sizing agents to improve their performance and desizing characteristics. However, the sizes containing CMC are very difficult to recycle. So PVA are combined with acrylics and acrylate type sizes.

(TEMPERATURE OF STARCH DURING THE PROCESS IS 85 C)

PROCESSING:

EVALUATION OF THE SIZING PROCESS: Weavers have been placing very stringent requirements on the quality of warp due to higher loom speeds and the need to produce first quality fabrics with an absolute minimum in defects. If the sizing is defective, the quality of the warp will be poor, which will affect the weaving operation and consequently the quality of the fabric.

The factors that need to be monitored and controlled on the slasher are as follows:

A) Size add-on control

B) Viscosity of size formulation

C) Yarn speed

D) Size encapsulation, which may be influenced by

E) Size temperature/viscosity

F) Size level

G) Amount of solids in the formulation and between different formulations

H) Tension in size box

I) Moisture in yarn

STARCH Starch was at one time the primary sizing agent for textiles.

CHEMICAL STRACTURE OF STARCH: Cellulose and starch have identical chemical constitution. They are both polymers of glucose, a sugar found in its pure form in grapes and often referred to as grape sugar. Glucose is only one of a family of ringed six carbon sugars that are referred to as carbohydrates because each carbon is associated with a molecule of water and have the empirical formula [C6H12O6_C6(H2O)6].

RECIPE OF MAKING STARCH:

A) SIGMA TEX

B) CORN STARCH (MAIZE)

C) ACRABASE

D) PETRASOFT

EXAMPLE :

MAKING THE BEST QUALITY OF STARCH: (AT RAJBY DENIM):

WATER: 750

TEXO: 75 KG

ACRABASE: 20 KG

SIGMA TEX: 7 KG

WAX: 2 KG

PETRASOFT: 5 KG

PROPERTIES OF GOOD STARCH MATERIAL:

Environmentally safe (nonpolluting) Recoverable and reusable (or treatable)

Good film former Low static propensity

Reasonable use economics No skimming tendency

Penetration of yarn bundle Easily removed (desized

Elasticity Easily prepared

Good film flexibility Lack of odor

Good specific adhesion No beam blocking

Good frictional properties (lubricity Compatible with other ingredients

Transparency Good abrasion resistance

Bacterial resistance (mildew) Neutral pH

Reasonable strength High fold endurance

Controllable viscosity (fluidity) Insensitive to high heat (overdrying

Water soluble or water dispersible Low BOD

Good hygroscopicity characteristics No build-up on dry cans

Uniformity Reduced shedding

Clean split at bust rods

Rapid drying

Improves weaving efficiencies

No redeposition of size

No effect on drying

Insensitive to changes in relative humidity

Reasonable extensibility

WEAVING INTRODUCTION:-

Weaving is a method of fabric production in which two distinct sets of yarns

or threads are interlaced at right angles to form a fabric or cloth. The other methods are knitting,

lace making, felting, and braiding or plaiting. The longitudinal threads are called the warp and

the lateral threads are the weft or filling. (Weft or woof is an old English word meaning "that

which is woven".) The method in which these threads are inter woven affects the characteristics

of the cloth.

LOOM:

Cloth is usually woven on a loom, a device that holds the warp threads in place while filling

threads are woven through them. A fabric band which meets this definition of cloth (warp

threads with a weft thread winding between) can also be made using other methods.

WEAVING DENIM FABRICS: Structure of Denim Fabrics Denim fabrics are woven by interlacing two sets of yarns perpendicular to one another in fabric form. Yarns in the machine direction are called warp yarns or warp ends, and these are interlaced with filling yarns or picks. The sequence or order of interlacing the two sets of yarns can be varied to produce many different weave designs. The finished fabric construction is determined by the number of warp and filling yarns per square inch or centimeter. For example, a typical construction for bottom weight denim may be 62 x 38. This is interpreted as 62 warp yarns per inch of width and 38 filling yarns per inch of length and always in that order. This thread count along with the yarn counts used will influence fabric properties such as weight, fabric tightness, cover, drape, hand, tensile strength, tear strength, and other fabric properties.

Yarn Flow in Weaving: 1)Warp yarns as seen are fed from the loom beam and pass over a whip roll or rollers, which control yarn tension variations during weaving motions. 2)The yarns are then directed through drop wires, heddles, and a comb-like device called a reed. The spaces between the reed wires across the width of the reed are called dents. Each reed has a certain number of dents per inch with 12 to 18 being the most common for denim and denim-type fabrics. 3)There are normally four warp yarns drawn per dent in standard 3/1 twill denim fabrics. The heddles, through which the yarn is threaded, are located in harness frames with a designed number of warp yarns drawn through each harness. 4)All warp yarns weaving alike in a design repeat occupy a given harness. The reed establishes the width of the warp yarn sheet and equal spacing of the yarns before weaving. It also is the mechanism used for pushing (beating-up) each inserted filling yarn (pick) into the body of the fabric at the fell of the cloth. The fell is the point where yarns become fabric. At this point, the warp yarn is in fabric form and ready to be collected on a cloth roll. Some machines have inspection stands that are backlighted for easy inspection of the fabric as it is woven before cloth roll take-up. 5)The flow of the filling yarn is somewhat simpler. The filling yarn is fed from large packages located outside of the actual weaving machine. The yarn comes off the package or packages and is wound onto a storage feeder that allows the yarn to be under consistent tension for each pick insertion. The yarn is then introduced to the filling insertion mechanism and inserted across the separated warp yarns, which have formed a tunnel or path called a weave shed.

Basic Weaving Motions

The five basic motions, which are shown in Figure, are required on a weaving machine to weave a

fabric such as denim and are detailed as follows:

Shedding:-

Shedding is the separation of the warp yarn sheet created by some harnesses lifting yarns upward and the remaining harnesses staying in a down position. Therefore, an opening (weave shed) is formed, providing a path for the filling yarns to follow. Cam shedding methods (also known as tappet) are used for simple fabric designs, while dobbies can weave small patterns into the fabric and jacquard systems with their ability to control each warp end are used to weave complex designs. Generally, the more harnesses that are employed on a given machine, the more complex the design. Most denim fabrics are woven on machines using cam shedding. Weaving machines running 3/1 and 2/2 denim fabrics will use four or eight harnesses for the ground weave, and in some cases, two additional harnesses for the selvage, if needed. Machines running 2/1 denim fabrics use three or six harnesses for the ground weave and can use two additional harnesses for the selvage, if required. The shape and profile of the cam determines the lifting motion of the connected harness. There is an individual cam controlling each harness on the weaving machine, while dobby looms use lifting jacks to control each harness and jacquard looms use a jacquard head and cord to control each warp end separately.

Filling Insertion:- The filling yarn is inserted through the weave shed by various methods. The oldest method, shuttle weaving, has been replaced to a large degree by methods using projectiles, rapiers, and air. Most denim fabrics are woven using projectile filling insertion or air jet filling insertion. The fastest method, air jet, can insert the yarn at a rate of 1400-2400 meters per minute. Most air jet machines weaving denim run at speeds of 600 to 900 picks per minute. Many machines today have pick-and-pick capability, meaning two filling yarn packages are available. Alternating the picks from different yarn packages helps to break up any repeating yarn pattern defects in a given package and decreases the yarn withdrawal rate from each package.

Beat-up:- As mentioned previously, the warp yarns pass through a comb-like device called the reed. The reed recedes away from the newly formed fabric during filling insertion and moves forward towards the fabric after pick insertion.The forward motion beats each inserted pick into the fabric body at the fell-of-the-cloth .

Warp Let-off:- The let-off device controls the rate the loom beam feeds the warp yarn into the machine. Tension sensing devices signal the let-off when more yarn is needed to maintain consistent warp yarn tension.

Fabric Take-up:- This mechanism controls the rate of removing the fabric from the weaving machine. The faster the rate of take-up, the fewer the picks per inch inserted into the fabric. The slower the rate of take-up, the more the picks per inch inserted into the fabric. The relationship between the let-off and take-up speeds determines the picks per inch in the fabric.

Yarn Twist Direction and Twill Line Direction:- For a more pronounced twill line in a denim fabric, the direction of twist in the warp yarn should be opposite to the twill direction in the fabric. For example, if Z twisted yarn in Figure 19 is woven into a right-hand twill (Figure 18), the twill line is less pronounced. If S twisted yarn is woven into the same fabric, then the twill line is more pronounced. It must be remembered that only Z-twist yarns are formed in open-end yarns, while ring-spun yarns have either Z or S. For that reason, open-end yarn can be used in left-hand twills when a more pronounced twill line is desirable. Having the twist direction opposite from the twill line direction also tends to make the fabric hand a little softer.

FINISHING MANAGER: ZAFAR SB

SUPERVISOR: AMIR SB

INTRODUCTION OF FINISHING: The Final woven fabric, wound on a cloth roll, is taken out from weaving machines at particular intervals and checked on inspection machines so that any possible weaving fault can be detected. In this quality control exercise, wherever any fault is seen, corrective measures are taken then and there only. The woven Denim Fabrics then goes through various finishing processes, such as brushing, singeing, washing, impregnation for dressing and drying. Brushing and singeing eliminate impurities and help to even the surface of denim fabric. Dressing regulates the hand and rigidity of the fabric while compressive shrinking manages its dimensional stability. The standard width denim fabrics is then sent for making up.

In this process, the fabric is cut into the desired width according to the size required. The made- up

denim fabric is then thoroughly checked for defects such as weaving defects, uneven dyeing, bleaching

and dyeing defects, oil stains, or patches. After inspection, the final product is categorized quality-wise.

The fault less fabrics are sent to the packaging department while the defective ones are sent for further

corrections.

STAGES OF FINISHING:

A) SINGEING

B) MERCERIZING

C) PAD STEAM/OVER DYE

D) SUNFORIZING

SINGEING: Technically,singeing refers to the burning-off of: Loose fibres not firmly bound into the yarn and/or fabric structure; Loose yarns not firmly bound into the fabric structure. Protruding fibre ends sticking out of the textile yarns and fabric..

Fabric Condition Before and After Singeing.

Advantages of Singeing/Objectives: *Singeing of a fabric is done in order to obtain a clean fabric surface which allows the structure of the fabric to be clearly seen. *Fabrics, which have been singed, soil less easily than un-singed fabrics. *The risk of pilling, especially with synthetics and their blends, is reduced in case of singed fabrics. *Singed fabrics allow printing of fine intricate patterns with high clarity and Detail.

Types of Singeing Machines:

There are three main types of singeing machines:

1. Plate singeing machine 2. Rotary-cylinder singeing machine 3. Gas singeing machine.

Gas Singeing Machine used at Rajby.

FUNDAMENTAL OF GAS SINGEING: The main purpose of singeing is to burn the protruding fibres from the yarn and/or fabric surface. In order to burn the protruding fibres, energy must be supplied. The supplied energy must be just enough to burn only the protruding fibres. As the temperature of the flame is too high (around 1300C), any regulation of this temperature..

MERCERIZING:

INTRODUCTION: Desiezing/Mercerizing removes the solution added to the fabric during the sizing process. Through the use of desizing agents, the sizing is either degraded or solubilized. Enzymatic desiezing, the most popular method of desiezing.. Mercerization is a process in which textiles (typicallycotton) are treated with a caustic (NaOH) solution to improve properties such as fiber strength, shrinkage resistance, luster, and dye affinity.

PROCESS:

CHEMICAL PROCESS:

Desiezing/Mercerizing is the first wet process treatment done on denim wash .The denim yarn is treated with starch (called Size) before weaving to give strength to yarn and avoid yarn breakage during weaving The process of removal of this starch is called Desiezing The most common enzymes used for textiles are Cellulose Enzymes. 1) They break the cotton fiber into smaller particles. 2) They work in specific temperature and pH. 3) A slight change in pH or Temperature will degrade the activity of Enzymes. 4) The enzymes are very specific in their reaction 5) All the cellulase Enzymes reduce fabric strength and gives weight loss that depends on the activity of the Enzymes Neutral Enzyme 1 . They provide better visual contrast between dark and light areas. 2. They are relatively less aggressive enzymes, hence gives washed look with minimum fabric weight loss. 3. Gives less back staining.

MECHANICAL PROCESS:

The fabric is first immersed in a caustic solution of about 23% strength and a relatively cool temperature of 60-90F (16-32C). It is then fed around a series of rollers (timing cans) which keep it flat and smooth while controlling the time of caustic exposure. The fabric is then sprayed with rinse water and then washed with a neutralizing chemical before final drying. The process will cause the fabric to shrink somewhat, so the fabric must be stretched before removing the caustic solution. Optimum dwell time of 45 seconds to 5 minutes (depending on the fabric) allows the yarn to swell and the fibers to untwist while tension is applied..

MERCERIZING MACHINE IN DENIM INDUSTRY

SUNFORIZING

INTRODUCTION: Sanforization is a process of treatment used for cotton fabrics mainly and most textiles made from natural or chemical fibres, patented by Sanford Lockwood Cluett (18741968) in 1930. It is a method of stretching, shrinking and fixing the woven cloth in both length and width before cutting and producing, to reduce the shrinkage which would otherwise occur after washing. The cloth is continually fed into the sanforizing machine and therein moistened with either water or steam. A rotating cylinder presses a rubber sleeve against another, heated, rotating cylinder. Thereby the sleeve briefly gets compressed and laterally expanded, afterwards relaxing to its normal thickness. The cloth to be treated is transported between rubber sleeve and heated cylinder and is forced to follow this brief compression and lateral expansion, and relaxation. It thus gets shrunk. The aim of the process is a cloth which does not shrink significantly during clothes production by cutting, ironing, sewing or, especially, by wearing and washing the finished clothes. Cloth and articles made from it may be labelled to have a specific shrink-proof value (if pre-shrunk), e.g., of under 1%.

SPECIFICATION OF SUNFORIZING MACHINE:

The purpose of a sanforizing machine or a shrinking machine is to pre-shrink, stabilize cotton fabrics and mixed cotton fabrics such as Denim.

It is made of 2 units :

The shrinking unit in which the compressive shrinkage is given by a thick Sanfor rubber belt using steam and mechanical pressure

The drying unit, also called the Palmer unit, in which the fabrics are dryed by an endless Sanfor polyester felt, which is called sanforizing felt, Palmer felt, Sanfor blanket or drying felt.

PROCESS OF SUNFORIZING MACHINE IN DENIM

(G,P) ROLLERS (R) RUBBER BELT (MOST IMPORTANT FOR SHRINKAGE)

(F) FABRIC (D) FAAT CYLINDER

WASHING (MANAGER: SHKEEL SB)

INTODUCTION: DENIM washing is known as one of the finishing treatment that has vast usage because of creating special appearance and updating clothes There is different methods of denim washing.

Provides the garments an identity and exclusive appearance and help in creating a brand image

Types of Washing:

DENIM WASHES ARE OF TWO TYPES:

1. Mechanical washes -Stone wash 2. Chemical washes -Denim bleaching -Enzyme wash -Acid wash

CHEMICAL WASHES:

Denim bleach: In this process a strong oxidative bleaching agent such as sodium hypochlorite or KMnO4 is added during the washing with or without stone addition. Discoloration produced is usually more apparent depending on strength of the bleach liquor quantity, temperature and treatment time. It is preferable to have strong bleach with short treatment time.

Process Cycle:

Enzyme Wash It is environmentally friendly wash. It involves the Application of organic enzymes that eat away at the fabric, i.e. the cellulose. When the desired color is achieved, the enzymes can be stopped by changing the alkalinity of the bath or its temperature. Post treatment includes final rinsing and softening cycle. The effects produced by the cellulose enzyme are: 1. Use of cellulose making the seams, hems, and pockets more noticeable 2. Salt pepper effect is color contrast effect. 3. Faded garment with acid cellulose enzyme provides less color contrast in proportion to garment washed with neutral cellulose enzymes.

(Enzyme Washes)

ACID WASH

It is done by tumbling the garments with pumice stones presoaked in a solution of sodium hypochlorite or potassium permanganate for localized bleaching resulting in a non uniform sharp blue/white contrast. In this wash the color contrast of the denim fabric can be enhanced by optical brightening. The advantage of this process is that it saves water as addition of water is not

PROCESS CYCLE:

LIMITATION OF ACID WASH: -Acid washed, indigo dyed denim has a tendency to yellow after wet processing. -The major cause is residual manganese due to incomplete neutralization, washing or Rising.

MECHANICAL WASHES

Stone wash: In the process of stone washing, freshly dyed jeans are loaded into large washing machines and tumbled with pumice stones to achieve a soft hand and desirable look. Variations in composition, hardness, size shape and porosity make these stones multifunctional. Pumice stones give the additional effect of a faded or worn look as it abrades the surface of the jeans , removing some dye particles from the surfaces of the yarn.

Softer stones would be used for light weight fabrics and more delicate items. Stone wt. /fabric wt. = 0.5 to 3 /1.

(Effect of Stone Wash)

PROBLEMS CAUSED BY STONES:

*Damage to wash machineries and garment due to stone to machine and machine to stone abrasion *Increase in labor to remove dust from finished garments. *Water pollution during disposal of used liquor. *Back staining and re deposition.

CHEMICALS ON DENIMS 1. Bleach fast Indigo 2. Anti-depositing agent 3. Dye stuffs with softener 4. Anti creasing agent 5. Wrinkle formation 6. White pigment

CONCLUSION

Denim is unique in its singular connection with one colour. The warp yarn is traditionally dyed with the blue pigment obtained from indigo dye. Until the introduction of synthetic dyes, at the end of the 19th century, indigo was the most significant natural dye known to mankind, linked with practical fabrics and work clothing. The durability of indigo as a color and it's darkness of tone made it a good choice, when frequent washing was not possible.

)

MILL UTILITIES THE MILL UTILITIES IS MOST IMPORTANT FOR ANY TEXTILE MILL. THE SOME UTILITIES AND THE INFO. ABOUT THE INDUSTRY RAJBY DENIM.

A) POWER HOUSE

B) BOILER

C) REVESE OSMOSIS (R.O) PLANT

D) COMPRESSOR

E) CHILLER

F) E.T.P PLANT

POWER HOUSE: There are three generators used for electricity supply.

Caterpillar: 2

Jenbacher: 1

NATURAL GAS GENERATOR SET FEATURES & SPECIFICATIONS OF

CATERPILLER:

Cat Natural Gas Generator Set Features:

Ratings from 65 to 6520kW Standby generators are powered

by Cat engines Wide range of factory-designed

options Easy to specify, permit, install and

test.

World-class fuel efficiency and low life-cycle costs

Excellent transient response and steady state performance

Emissions compliance with most worldwide regulations

Single source

MACHINE SPECIFICATION:

THE GENERATOR USED AT RAJBY INDUSTRIES

Maximum Continuous Rating 1560kW

Fuel Type Natural Gas, Biogas, Coal Gas

Maximum Electrical Efficiency 43.3

Maximum Standby Rating -

Frequency 50/60Hz

rpm 1500rpm

JENBAKER GENERATOR:

Features & Benefits:

Supercharger ensures homogenous mixture at low gas pressures. Two-stage mixture cooling enables high flexibility. Turbocharger bypass evens out extreme operating conditions. High-performance long-life spark plug enables reliable operation.

1 MW GENERATOR OF JENBAKER

JENBAKER GENERATOR USED AT RAJBY INDUSTRIES

TOTAL A ELECTRIC SUPPLY TO THE INDUSTRY: 1.5MW + 1.5MW + 1MW= 4MW (POWER SUPPLY DELEIVERD TO RAJBY DENIM)

BOILER

INTRODUCTION: A boiler or steam generator is a device used to create steam by applying heat energy to water.

The size of the boiler is matched to the size of the facility.

If the boiler is oversized, the fuel bills will be excessive. If the boiler is undersized, it may not generate enough heat in winter.

Boiler Types and Classifications

There are two general types of boilers:

1) Fire-tube

2) Water-tube.

Boilers are classified as "high-pressure" or "low-pressure" and "steam boiler" or "hot water boiler.

FIRE-TUBE BOILER

WATER-TUBE BOILER

FEATURES AND SPECIFICATION:

Fire-tube Boilers

WROUGHT IRON Boiler used at RAJBY INDUSTRIES In fire-tube boilers, combustion gases pass through the inside of the tubes with water surrounding the outside of the tubes. The advantages of a fire-tube boiler are its simple construction and less rigid water treatment requirements. The most common fire-tube boilers used in facility heating applications are often referred to as ''scotch'' or ''scotch marine'' boilers, as this boiler type was commonly used for marine service because of its compact size (fire-box integral with boiler section)

INERT PORTION OF 3-FACE FIRE-TUBE BOILER

CHILLER

A water chiller is a mechanical device used to facilitate heat exchange from water to

a refrigerant in a closed loop system. The refrigerant is then pumped to a location where the

waste heat is transferred to the atmosphere. PROCESS

In hydroponics, pumps, lights and ambient heat can warm the reservoir water temperatures, leading to plant root and health problems. For ideal plant health, a chiller can be used to lower the water temperature below ambient level; 68F (20C) is a good temperature for most plants. This results in healthy root production and efficient absorption of nutrients.

In air conditioning, chilled water is often used to cool a building's air and equipment, especially in situations where many individual rooms must be controlled separately, such as a hotel. A chiller lowers water temperature to between 40 and 45F before the water is pumped to the location to be cooled.

Safety Issues: Chillers are typically located in a mechanical equipment rooms. Each type of refrigerant used in a chiller compressor has specific safety requirements for leak detection and emergency Ven. . (THE CHILLER PROCESS AT RAJBY)

REVERSE OSMOSIS (R.O) PLANT:

R.O PLANT WE RECYCLE

WATER

How does Reverse Osmosis work?

Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane. This membrane technology is not properly a filtration method. In RO, an applied pressure is used to overcome osmotic pressure, a colligative property, that is driven by chemical potential, a thermodynamic parameter. RO can remove many types of molecules and ions from solutions, and is used in both industrial processes and producing potable water. The result is the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side. To be "selective", this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution (such as the solvent) to pass freely.

MAIN PROSPECT:

REVERSE OSMOSIS PLANT: This is a process that exposes water under pressure to a semi-permeable membrane with a very fine pore structure. Because most inorganic contaminants are of a larger molecular size than water the membrane rejects certain contaminants minerals and a large part of the water. The portion of water that passes through the membrane is stripped of inorganic compounds and trace minerals. Because many synthetic chemicals like herbicides and pesticides are smaller molecularly than water... an R.O. system must also be used in conjunction with a carbon filter. R.O. systems require adequate water pressure and extensive maintenance. Because most point-of-use R.O. systems produce less than 1 gal. per hour they require a diaphragmed storage tank. Reverse osmosis typically wastes 2 to 3 gallons of water for every gallon it produces and has an 18 to 24 cents per gallon usage cost.

Industrial Applications: Boiler Feed Water Treatment: RO is used to reduce the solids content of waters prior to feeding into

boilers for the power generation and other industries

Pharmaceutical: Reverse osmosis is an approved treatment process for the production of United States

Pharmacopeia (USP) grade water for pharmaceutical applications

R.O in the Power Generation Industry: The use of RO has grown rapidly throughout the industrial sector, but in no industry more quickly than

in the power generation sector. Globally, water treatment for power generation is estimated at more

than 30 percent of all industrial water treatment sales.

Most electric power plants that use coal, gas, oil or nuclear fuel create steam that turns a turbine to

produce electricity. Impurities in the steam can cause problems, reducing the amount of electricity that

is produced. This costs power plants money and increases the amount of fuel that must be consumed to

provide the necessary amount of electricity. In extreme cases, impurities in the process water can lead

to damage and downtime that prevents a plant from producing electricity.

Historically, power producers have used a combination of coagulation, flocculation and ion exchange

resin beds to create high purity water for making steam. However, these technologies require the use of

hazardous chemicals, including sulfuric acid and caustic soda. As a consequence, many power plant

operators are adopting RO membrane filtration as a water purification technology because it does not

require the use of hazardous chemicals. RO provides additional operational and cost benefits as well.

Cost benefits of R.O: R.O is increasingly being adopted by power producers as a treatment method for purifying boiler feed

water, makeup water and in zero-liquid discharge applications. The injection of high purity water

produced by RO technology into a gas turbine can improve operating efficiency and increase energy

output by 10 percent or more.

There are other cost benefits as well. For example, the prices of acid and caustic solutions continue to

rise while the prices of R.O units and membrane elements continue to decrease. The primary cost for

operating R.O systems is electricity, and since these systems consume very little energy, operating costs

are relatively low.

The effluent discharged to the sewer typically contains between 200 to 10,000 parts per million (ppm)

total dissolved solids (TDS). With the proper pretreatment technology followed by RO, this water can be

recycled.

WE ARE THE STUDENT OF N.E.D UNIVERSITY OF ENGG. AND TECHANOLOGY KARACHI. ARE VERY

THANKUL TO HEAD , THE DIRECTOR AND THE STAFF THAT GIVE US THE OPPORTUNITY AND THE FOR

THE ALLOWING TO DO THE INTERNSHIP AT RAJBY DENIM.. THIS INTERNSHIP REALLY HELPED US IN THE

NEAR FUTURE

THANK YOU

GROUP MEMBERS:

1) SYED TALHA HUSSAINI (TEXTILE ENGG. UNDERGRADUATE STUDENT)

2) KASHIF NAEEM (TEXTLE ENGG. UNDERGRADUTE STUDENT)

3) ABDUL SAMAD SHEIKH (TEXTILE ENGG. UNDERGRADUTE STUDENT)

4) FARAZ ALI (TEXTILE ENGG. UNDERGRADUTE STUDENT)

ITS A GREAT EXPERIENCE TO THE INTERNSHIP AT RAJBY DENIM. THIS INTERNSHIP HELPED US FOR UNDER STANDING THE PROCESSES AND THE WORKING OF MACHINE AND MUCH MORE.RAJBY IS THE BEST DENIM MILL WHERE THE STUDENT CAN ACHIVED MUCH KNOWNLEAGE ABOUT THE PROCESSING AND MECHANICAL FIELD (THANK YOU RAJBY)