Arvind Textile Internship Report-Final 2015

A Report on Textile Internship

Bachelor of Fashion Technology (Apparel Production)

Submitted By: Bhupinder Pawar Divyanshu Sagar Shashank Sachan Shikhar Maurya Tushty Choudhary

                                       Under the Guidance of                                          Ms. Shipra Sharma

Department of Fashion Technology National Institute of Fashion Technology, Kangra, August, 2015 Certificate

This is to certify that this Project Report titled “Textile Internship – Arvind Shirting Division is based on our original research work, conducted under the guidance of Ms. Shipra Sharma towards partial fulfillment of the requirement for award of the Bachelor’s Degree in Fashion Technology (Apparel Production), of the National Institute of Fashion Technology, Kangra. No part of this work has been copied from any other source. Material, wherever borrowed has been duly acknowledged.

Bhupinder Pawar Divyanshu Sagar Shashank Sachan Shikhar Maurya Tushty Choudhary B.F.Tech; Sem V NIFT Kangra

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Acknowledgement At the outset, we wish to express our gratitude to everybody who has assisted in formulation of this report. There are many to whom expression of gratitude is inevitable, but there some special people who has to be given prominence, without whom we would not have reached the conclusion of this project so quickly and so efficiently. We would like to thank Arvind, Santej unit for giving us the opportunity to undergo a training in the textile department and for extending their support towards us all throughout our internship. No amount of Gratitude is adequate for the HR Manager, Ms. Shivangi Sheth and Mr. Shubhanish Malhotra, Santej Unit, Arvind Mills for their consent in allowing us to conduct our internship in their venerated institution. We also wish to thank the various department heads, managers, assistants and supervisors for their technical guidance and assistance. We wish to thank the Director Mr.S K Bala Sidharth and Mrs. Shipra Sharma providing this wonderful opportunity and motivation. We take this opportunity to express our affection towards our parents for their consistent faith and support.

Bhupinder Pawar Divyanshu Sagar Shashank Sachan Shikhar Maurya Tushty Choudhary B.F.Tech; Sem V NIFT Kangra

Table of Contents Page | 3

1. Abstract 2. Company profile 1.1. History 1.2. Vision and values 3. Aim 4. Course of action 5. Spinning department 5.1. Blow room 5.2. Carding 5.3. Drawing 5.4. Combing 5.5. Speed frame(rovings) 5.6. Ring frame 5.7. Two-for-one twisting 5.8. Singeing 5.9. Layout 6. Yarn dyeing department 6.1. Soft winding 6.2. Pressing 6.3. Dyeing 6.4. Hydro extraction 6.5. Radio frequency dryer 6.6. Re winding 6.7. Layout 7. Warping department 7.1. Direct warping Page | 4

7.2. Sectional warping 7.3. Layout 8. Sizing department 8.1. Purpose 8.2. Types of sizing 8.3. Properties of sized yarns 8.4. Layout 9. Weaving department 9.1. Air jet looms 9.2. Layout 10. Processing and finishing department 10.1.

Classification of finishes

10.2.

Layout

11. Inspection and quality assurance department 12. Testing department 13. Packaging department 14. Environmental factors 15. Conclusion 16. Bibliography

ABSTRACT: In this internship module we have learnt lot of things. We have gone through seven departments that are spinning department, yarn dyeing department, warping department, Page | 5

sizing department, weaving department and processing and finishing department in this time period. At the end of the internship we come to know about minute details of textile industry and how it works. We learnt manufacturing and planning process of the industry. Under this internship schedule, all the qualified appointed people helped and guided us in understanding and learning different aspects of the industry. In weaving division, we checked the PPC department, QA department, raw material department, warping department, sizing department, auto drawing department, production department, inspection and folding department, and also utility and maintenance department.

AIM: The project is based on a 2 weeks internship, in Arvind Mills Shirting Department. It covers all the information and learning experiences related to manufacturing of textiles, fine shirting fabric in this case and all the processes involved namely: 

Spinning



Dyeing



Warp Preparation



Weaving



Finishing



Testing

The main objectives of the project/internship were: 1. Understanding basic principles of production of textiles. 2. In depth study and understanding of all process involved in textile production and the machinery and equipment used. 3. Knowledge about the company. 4. Understanding the company’s process flow in production. 5. Study the work environment and practices followed for textile production.

COURSE OF ACTION: We devoted two days to visit each department related to the production of fine shirting fabrics. In the departments, head of departments were assigned to us, for detailed Page | 6

explanation of the process involved. The head of department showed us the individual processes, explained the work flow and showed us associated machinery. We maintained a learning diary and took down noted on all information that we could acquire from the department. We then spent three to five hours, depending upon the process, in each department, exploring the various machine features, writing down specifications and talking to the machine operators about the various problems faced during production. After the industrial visit, we would go home and take down additional information from the internet and any other available source, and compile this document side by side, so as to not miss out on any important details.

COMPANY PROFILE: History

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Founded in 1930 when the world suffered the great depression, Arvind mills was setup by Kasturbhai, Narottambhai and Chimanbhai following the swadeshi movement which left a huge demand for super fine fabrics in india. Arvind Limited started with a share capital of Rs 2,525,000 ($55,000) in the year 1931. With the aim of manufacturing the high-end superfine fabrics Arvind invested in very sophisticated technology. With 52,560 ring spindles, 2552 doubling spindles and 1122 looms it was one of the few companies in those days to start along with spinning and weaving facilities in addition to full-fledged facilities for dyeing, bleaching, finishing and mercerizing. Steadily producing high quality fabrics, year after year, Arvind took its place amongst the foremost textile units in the country. In 1987-88 Arvind entered the export market for two sections -Denim for leisure & fashion wear and high quality fabric for cotton shirting and trousers. By 1991 Arvind reached 1600 million meters of Denim per year and it was the third largest producer of Denim in the world. This expansion was possible thanks to a change in strategy called Reno vision shifted their focus from the domestic market to the international market. In 1997 Arvind set up a state-of-the-art shirting, bottom weights and knits facility, the largest of its kind in India, at Santej. With Arvind’s concern for environment a most modern effluent treatment facility with zero effluent discharge capability was also established. Arvind has carved out an aggressive strategy to verticalize its current operations by setting up worldscale garmenting facilities and offering a one-stop shop service, by offering garment packages to its international and domestic customers. With our growing global footprints, Arvind has carved a niche with brand names like Arrow, Flying Machine, USPA, New Port, Mega Mart and The Arvind Store.

SPINNING DEPARTMENT:

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• Blow Room (Bale opening, cleaning) • Carding • Pre-Drawing • Unilap Machines • Combing • Post-Drawing • Speed Frames • Ring Frames • Winding • Assembly Winding(plied yarns) • Two For One (T.F.O) • Singeing(optional)

Spinning is the process of conversion of fiber to yarn. It is composed of about 90 percent cellulose and about 6 percent moisture; the remainder consists of natural impurities. The outer surface of the fiber is covered with a protective wax like coating which gives the fiber a somewhat adhesive quality.

Blow Room With all harvesting methods, however, the cotton seed, together with the fibers, always gets into the ginning

plant

where it is broken up into trash and seed-coat fragments. This means that ginned cotton is always contaminated with trash and dust particles and that

an

intensive cleaning is only possible in the spinning mill. Nep content increases drastically with mechanical harvesting,Fig. ginning 1.1 and subsequent cleaning process. The reduction of the trash content which is necessary for improving cotton grade and appearance unfortunately results in a higher nep content level. The basic purpose of Blow room is to supply

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· Small fibre tufts · Clean fibre tufts · Homogeneously blended tufts if more than one variety of fibre is used to carding machine without increasing fibre rupture, fibre neps, broken seed particles and without removing more good fibres. Machines Used: 1. For Extracting Raw Cotton : Trutzschler Blendomat BDT 019 Cotton is passed from bales and then to apron. Apron moves cotton to blending apron. Blending apron has sharp spikes the raise cotton until part of it is knocked off by the roll. Some of the cotton stays on apron. The cotton knocked back by roll and continues to blend until picked up again by apron. Another roll strips off cotton that was not knocked back by previous roll. Fig. Cotton 1.2 falls on conveyor belt and is carried to next process that is blending through an overhead duct. There was only one such machine there. 2. For Opening: Trutzschler BO 046 Lint cotton falls on apron and passes between feeder rolls to beater cylinder. The rapidly whirling beater blades take off small tufts of cotton, knock out trash, and loosen up the mass. Air suction through cotton takes out dirt and trash. Conveyor belt passes cotton to another type of beater. From beater the cotton passes to a conveyor and is carried to picker. It is necessary in order to loosen hard lumps of fiber and Fig. 1.3

disentangle them and to press the raw fibre in a temporary lap. There were three such machines there. 3. Axi flow cleaner or AFC : Trutzschler 052-2502

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Fig. 1.4

Objective of AFC is separation of

heavy parts (impurities) from cotton.

The opened up mass of fiber rotates around two cleaning rollers (beaters) with cylinder steel pins which beat the fiber material, allowing the coarse particles to be separated. The time (in hours) of the passage of material can be regulated. The speed range of the beaters varies from 400-600 rpm. There were three such machines there. 4. ASTA : Trutzschler ASTA 800 Objective of ASTA is Heavy trash separation from cotton. The air and material enters the separation tank in a stream via upper channel and hit baffle plates. Heavy particles are removed away from the lighter fibers by negative acceleration and the force of gravity. The lower channel generates an opulent air stream in the area of baffle plates, which guides the fibers to the outlet. There were three such machines there.

5. DUSTEX : Trutzschler CVT-4 1600

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Fig. 1.5

Dust removal is not an easy operation since the dust particles are completely enclosed in the flocks & hence are back during suction. The suction units remove dust 64% dust. There were three such machines there. 6. LOPTEX Breaker and Finisher These are basically used to remove some foreign impurities that might have adhered to the cotton fibre right from the start of the ginning process. There were six such machines there. 7. T.V.D Fan The main purpose of this fan is to pass on the cotton tufts to the carding machine.

Carding

Fig. 1.6

Fig. 1.7

Carding is the process of removing impurities from fibers and producing a carded sliver of parallelized and straightened fibers 

Before the raw stock can be made into yarn, the remaining impurities must be removed, the fibers must be disentangles, and they must be straightened.

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

The straightening process puts the fibers into somewhat parallel CARDING.



This work is done by carding machine.



The lap is passed through a beater section and drawn on rapidly revolving cylinder covered with very fine hooks or wire brushes slowly moves concentrically above this cylinder.



As the cylinder rotates, the cotton is pulled by the cylinder through the small gap under the brushes; the teasing action removes the remaining trashes, disentangles the fibers, and arranges them in a relatively parallel manner in form of a thin web.



This web is drawn through a funnel shaped device that molds it into a round rope like mass called card sliver.



After carding, the carded slivers go to the draw frame.

Drawing Drawing is the process where the fibres are blended, straightened and the number of fibres in the sliver increased in order to achieve the desired linear density in the spinning process. The drawing process also improves the uniformity or evenness of the sliver. The number of drawing passages utilised depends on the spinning system used and the end products. In arvind mills, the sliver is drawn through the draw frame twice. One is after the carding stage and another after the combing stage. They were also known there as SB-drawing & RSB-Drawing. After SB drawing the cans are fed to the unilap machine for converting slivers into a tap or lap. This conversion is done because the fibres cannot be fed to the comber in a sliver form. Inside an Unilap Machine, the three-over-three drafting system ensures high fleece quality through optimum finishing drafting and parallelisation of the fibres. High-quality laps or tapes are produced by means of two lapping rollers and a variable production speed. The length of each tape/ lap is 260 m and the width of the tape is 302 mm.

Combing

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In general, combing is done to remove the short length fibres. For example fibre shorter than 21 mm. The comb is a filter or sieve for short fibre length. Combing is a mechanical sieve and will not remove any containment that looks like a fibre being combed.

The rectilinear comb uses a circular comb mounted on a drum to comb out the fringe and remove short fibre (set by a scale so fibres less than for example 25mm are removed) not held by a clamping mechanism. The row of pins known as a Top comb is a very fine tooth comb, for example 25teeth per inch, it is inserted in cylindrical combed fringe to act as an impediment to contaminates (Burr, seed etc) flow. The top comb acts as an impediment to contamination moving into a combed sliver. On a next circular combing short finer and contaminates are removed. The circular combing without shot fibres are placed on a moving belt in an overlapping motion. The motion of circular combing and top comb insertion is repeated and combed fibers - now called tuft are overlapped. The overlapping produces some cohesion allowing the tuft then to be twisted to form a combed sliver. This sliver is weak and unsuitable for spinning. The short fibres are carried by an underground duct to the blow room again.

Speed Frame (Roving’s) In preparation for ring spinning, the sliver needs to be condensed into a finer strand known as a roving before it can be spun into a yarn. It is an intermediate process in which fibers are converted into low twist lea called roving. The sliver which is taken from comber is thicker so it is not suitable for manufacturing of yarn. Its purpose is to prepare input package for next process. This package is to prepare on a small compact package called bobbins. Roving machine is complicated, liable to fault, causes defect adds to the production costs and deliver the product. In this winding operation that makes us roving frame complex.

There are two main basic reasons for using speed frame: 

The roving sliver is thick and untwisted. Because of it hairiness and fly is created. So draft is needed to reduce the linear density of sliver. The ring drafting arrangement is not capable that it may process the roving sliver to make the yarn. P a g e | 14



Draw frame can represent the worst conceivable mode of transport and presentation of feed material to the ring spinning frame.

They were using three types of speed frame machines: Toyota, LR, Ginser. LR m/c had 144 spindles running at an RPM of 800-900 and the Toyota and Ginser had 120 spindles and were running at an RPM of 1000-1100. More finer counts like 82s, 95s were being made on LR machine, whereas Toyota machines were used for count range below 60s.

Ring Frame A ring frame was constructed from cast iron, and later pressed steel. On each side of the frame are the spindles, above them are draughting (drafting) rollers and on top is a creel loaded with bobbins of roving. The roving (unspun thread) passes downwards from the bobbins to the draughting rollers. Here the back roller steadied the incoming thread, while the front rollers rotated faster, pulling the roving out and making the fibres more parallel. The rollers are individually adjustable, originally by mean of levers and weights. The attenuated roving now passes through a thread guide that is adjusted to be centred above the spindle. Thread guides are on a thread rail which allows them to be hinged out of the way for doffing or piecing a broken thread. The attenuated roving passes down to the spindle assembly, where it is threaded though a small D ring called the traveller. The traveller moves along the ring. It is this that gives the ring frame its name. From here the thread is attached to the existing thread on the spindle. The up and down ring rail motion guides the thread onto the bobbin into the shape required: i.e. a cop. The lifting must be adjusted for different yarn counts. These machines were imparting Z-Twist to the yarn.

Winding The main purpose of winding machines that they were using is to transfer the ring yarn obtained from ring spinning into a cone form. These machines were installed with LOEPFE YARN MASTER, which is used for detecting the unwanted presence of neps, foreign matter, colour contamination and hairiness. When encountered, the machine used to cut the thread from that position, removing the abnormalities.

Two - For – One Twisting (TFO) The process of twisting is an indispensable means of improving certain yarn properties and satisfying textile requirements that cannot be fulfilled by the single yarns. The method of P a g e | 15

twisting two or more single yarns is called doubling or folding or ply twisting. Such yarns are designated as doubled yarn, folded yarn or plied yarn and the machines intended for the purpose

are

called

doublers,

ply-twisters

or

two-for-one

(TFO)

twisters.

Traditionally, ring doublers were used for ply twisting spun yarns and uptwisters were used for twisting filament yarns. Now-a-days, TFO twisters are gaining world-wide acceptance in both spun yarn and filament yarn sectors mainly because of their inherent advantages like (1) production of long length of knot free yarns which facilitates better performance in the subsequent processes and (2) higher productivity.

Singeing Singeing of a yarn is done in order to obtain a clean yarn surface which allows the structure of the fabric to be clearly seen. Yarns, which have been singed, soil less easily than unsinged yarns. The risk of pilling is reduced in case of singed fabrics. Singed fabrics allow printing of fine intricate patterns with high clarity and detail. The risk of skittery dyeings with singed articles dyed in dark shades is considerably reduced, as randomly protruding fibres are removed in singeing which could cause diffused reflection of light. SSM GSX3 and PEASS were used for yarn singeing running at a speed of 1500m/min and a maximum take up package width of 280mm. RJK high speed cone/cheese winding was being used for removing the adhered burnt particles from the yarn surface and provides a final finish to the yarn surface.

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YARN DYEING DEPARTMENT:

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• Soft Winding • Pressing Machine (Loading/Unloading) • Package Dyeing (Scouring, Bleaching, Dyeing, After Treatment) • Hydro Extractor • R.F Dryer • Q.A Check • Rewinding

Soft Winding The soft package winding is the most important pre dying operation, which directly affects not only the dyeing quality but also post dyeing operations such as rejects, wastages and poor unwinding, thread breakages etc. Well wound is half dyed, is the popular saying which is very correct in the context of package dyeing, because we can’t expect miracles from the most advanced dyeing machinery, if our packages are of poor quality. Although different technologies of winding when operated carefully provides satisfactory results, but in order to insure uniformity and consistently good winding, precise adjustment and careful maintenance of the equipment is necessary and the operators must be trained and closely supervised. Factors like count of the yarn, angle of winding, yarn tension during winding, diameter and traverse of the package, the stability of the package, the winding ratio, the compactness and size of the feed package all affect the package make up and must be considered while selecting a machine for soft package winding.

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The most compact part of any package is its edges or shoulders, where the yarn turns the corner and this is the most difficult place to wet out and to penetrate. Incomplete penetration will cause it to dye lighter or not at all. Crossing or Winding Angle It is the angle at which the yarn crosses each other on a wound package, smaller the crossing angle denser will be the package. Winding Ratio It is the no. of turns of yarn per revolution of the package, or distance between the threads of layer. More the no. of turns per revolution more is the density. Increasing the distance between the threads of a layer decreases the density. Package Stability It is the tendency of wound yarn on the package holder to remain stable. If the yarn layers does not hold good on the package holder, the package may deform easily in subsequent processing. The Package The yarn to be dyed is first to be wound into a package. The weight and diameter of the package is limited by the space available between the spindles (pitch) and by the levelness obtained when a dyeing is carried out using a particular dyestuff. The package dimensions and weight are influenced by the type and construction of yarn to be processed, class of the dyestuffs, machine flow rate, end use of the dyed substrate and package holder eg. Spring, cheese, or cone. Package Holder: SS Dye Springs The dye springs are most commonly used package holder, on which the yarn is wound offers the advantages such as these are reusable, compressible, making a perfect column after pressing, spacers etc. are not used between the individual packages, thus reducing the possibility of channelling, dye springs offers much lesser resistance to the liquor flow through the packages. Due to high compression possibility the dyeing machines can be loaded to a higher capacity and liquor ratio can be reduced for better economy of the process.

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Pressing Pressing is done usually to compress the soft package and prepares it for subsequent chemical operations. An over head dye press is used for this purpose which exerts an approx pressure of 132 psi and compresses the soft package by 15%. At first the packages are loaded on the spindles and then pressed together. This is known as loading. These compressed packages are then sent for dyeing. After the completion of dyeing, these packages are again brought to the pressing area and then previously exerted pressure is released. This is known as unloading. Max. Capacity of each spindle is 10 packages. And for a minimum lot of let’s say, 72 kg - 6 spindles are used and for a maximum lot of 500 kg - 42 spindles are used.

Dyeing Dyeing is

the

process

of

adding

colour

to textile products

like fibres, yarns,

and fabrics. Dyeing is normally done in a special solution containing dyes and particular chemical material. After dyeing, dye molecules have uncut chemical bond with fibre molecules. The temperature and time controlling are two key factors in dyeing. There are mainly two classes of dye, natural and man-made. Yarn dyeing is a special type of dying process. Yarns are dyed in package or hank form by yarn dyeing process. It is slightly different from woven or knits dyeing. Dyed yarns are used for making striped woven or knits fabric or solid dyed yarn fabric or in sweater manufacturing. In arvind, they were using HTHP package dyeing machines for yarn dyeing and the dyeing section is divided into 4 phases on the basis of the machines capacity. In the dyeing section; dyeing is done according to the approved sample dyeing recipe. Different parameters are maintained during dyeing like; temperature, pressure, time etc. when dyed yarn shade is matches with the approved sample then it is sent for further processes otherwise, it is re-dyed.

Hydro-Extraction P a g e | 20

Hydro extractors are machines which are used in processing industry. The wet material is placed in the extractor, which has a wall of perforated metal, generally stainless steel. The internal drum rotates at high speed thus throwing out the water contained in it. The use of hydro extractor significantly reduces the energy required to dry any material. The machines used for hydro extraction in arvind were capable of removing upto 25% water. Fig. 2.1

WARPING DEPARTMENT: Warping The parallel winding of warp ends from many winding packages (cone, cheese) on to a common package (warp beam) is called warping.

Operations Creation, out of a limited number of warp threads, of a warp composed of any number of threads with the desired length;  Arrangement of above-mentioned threads according to the desired sequence; Manufacturing of a warp beam with said characteristics.

Objectives To arrange a convenient number of warp yarns of related length so that they can be collect on a single warp beam as a continuous sheet of yarns which can be used for sizing or next process.

Importance 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 pre- determined length of yarn. P a g e | 21

Combination of small packages. Accelerating the next process. Requirements 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.

Direct Warping Direct warping also called Beam warping/High Speed warping. In Direct warping the yarn is wound parallel on the warping beam. All the yarns are wound at once and simple flanged beam is used. It is a very high speed process and is used for making fabric of single colour. Features:

    

It is used to make common fabrics in large quantities It is used to produce weavers beam from single yarn The production is high Large amount of yarn is required to produce a weavers beam Simple flanged beam is used and drums are not required

Sectional Warping Fig. 3.1

In sectional warping equal length of yarn is first wound in small sections or sheets on a drum. Then from the drum it is transferred to the beam. By this process we directly get the weavers beam. This is a two stage method and is used for making fancy fabrics.

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Using this method, first the no. of sections is calculated, by dividing the total ends/ creel capacity. Principle: 

Sectional warping is used for short runs especially for fancy



pattern fabrics. In this case sections of the warp which may contain up to 1000 ends are first wound onto a drum tapered with a given cone



angle. So cross wound sections are combined on the drum & thus each layer ofFig. warp 3.2



contains the same number of ends on the drum. Then the warp threads altogether are transferred onto a weavers beam by unwinding the drum.

 In this method the warp threads are not necessarily processed in sizing. Features:  This is suitable for making checked, stripped or other fancy fabric.  We directly obtain weaver’s beam from this process  As sizing is not done, so multi-ply yarns or yarns which do not require sizing are used  Small amount of yarn is required to produce the weaver’s beam  Sectional warping is used to produce a   

warp beam with a greater member if ends The production is less in sectional warping The yarn tension is less uniform It is less efficient than high speed warping Fig. 3.3

SIZING DEPARTMENT: Sizing is one of the most important terms for weaving technology. After winding and warping, sizing of yarn is done during beam preparation. Sizing is done by applying various types of size materials on the yarn. During application of size materials steam is needed. Sizing is a protective process. The process of applying a protective adhesive coating upon the yarns surface is called is sizing. This is the most important operation to attain maximum weaving efficiency especially for blended and filament yarns. Sizing is also called as the heart of weaving.

Purpose P a g e | 23

To improve the weave ability of warp yarn by making it more resistance to action of weaving like absorption, friction, tension, etc. To maintain good quality fabric by reducing hairiness, weakness and by increasing smoothness and absorbency of yarn. Tensile or breaking strength of cellulosic yarn is increased by sizing

Elasticity of the yarn is also increased. By adding size materials yarn weight is increased. To increase the frictional resistance. Projected fibres are removed by this process. To reduce electrostatic formation.

Types of Sizing Pure sizing: when the size pick up % is about 3 – 10 % it is called pure sizing. Light sizing: when the size pick up % is about 11 -16% it is called light sizing. Medium sizing: when the size pick up % is about 17 – 40 % it is called medium sizing. Heavy sizing: when the size pick up % is above 40 % then it is called heavy sizing.

Properties of Sized Yarn         

Higher elasticity Higher yarn strength Lower flexibility Lower extension or elongation Lower frictional resistance Increased smoothness Less weaknesses Insensible to over drying Less hairiness

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Fig. 4.1

Sizing monitoring:- The sizing process is automatically monitored. All set points are specified with upper and lower tolerance limits. Deviations from the programmed value are displayed at once and instructions for their rectification are explained in the language of the operator. Controlled tensions:- The special arrangement of rollers in the 3- roller set prevents threads from slipping through and keeps the thread tension constant in the dry split section when changing beams. Reproducible size cooking:- The SIZEMIX cooker, equipped with a high powered agitator ensures homogeneous liquor. The cooker is programmed via the size recipe at the machine PC. In this way, cooking temperature, water quantity and cooking time are preset and automatically maintained. Attendance takes place optionally from the PC or directly at the cooker. Viscosity of size paste:- Viscosity of size pate should not deviate from required value. Less viscose paste makes adhesion of size material well but coating on the surface of the yarn is not done properly. While paste with higher viscosity coats the yarn very well but adhesion of paste into the core of yarn in terms of increasing its strength is not done properly.

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Size box temperature control:- The degree of size penetration and coating depends not only on the nature of yarn & the size solution but also upon the viscosity which in turn largely depends on the temperature. It should be about 200F°-206F°. Fluctuation should be ±3 F°. The temperature gauge should be installed on the size box. Perforated copper pipe lining is laid in the bottom of size box to supply the steam for keeping the paste warm up to the above mentioned temperature. Low temperature will make gelling of paste which will not penetrate through the yarn and higher temperature create thinning of the size paste which is also unsuitable to be used as sticky paste. So to maintain the temperature of above value is very important. If the size paste is prepared with rich PVA or CMC then temperature of 75C° to 80C° is sufficient. Moisture content in the yarn:- The moisture content in the sized yarn should not go below 6%. Otherwise the coating of size film will not allow absorbing moisture in the loom shed which is necessary for good working. For this moisture monitor is being supplied with the machine. The temperature of the drying cylinders should be kept 140-150 to maintain 6-7% moisture in the yarn. Programming the machine:- The easy to follow visualization and recipe management, in which all the machine and textile parameters are stored, permit fast and simple programming.

The temperature varied in these machines from 71 C - 140C and the speed varies in between 40-50 m/min. The production of beam dyed warp beams was 3-4 beams/shift and that of the sectional warped beam was of 5-6 beams/shift. The maximum ends per beam were 15000 and minimum ends per beam were 2000. They were also using 1 size paste mixer and 3 size paste cookers, each of 1000 l capacity out of which one was open and 2 were closed. In the open cooker a temperature of 90C was maintained and the paste was cooked for 30 minutes. And in the closed cooker a temperature of 100C was maintained and the paste was cooked for 40 minutes.

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WEAVING DEPARTMENT: Weaving is the interlacing of warp filling yarns perpendicular to each other at 90 degree. These are practically an endless number of ways of interlacing warp and filling yarn.

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Fig. 5.1

The waving machines are named after their filling insertion system. Schematics of the filling insertion systems that are used in the market are:      

Shuttle Projectile Rigid rapier Flexible rapier Air jet Water jet

Based on the filling insertion system, the weaving machine can be classified as shuttle and shuttle less weaving machines. Shuttle looms have been used for centuries to make woven fabrics.

Air Jet Looms Or Air Jet Weft Insertion System This system is most improved form of weft insertion. In this system, the mechanism and machine parts have been totally eliminated used to drive the weft insertion source. This facilitates to increase the insertion rate up to 2500 p.p.m. This type of machine is firstly commercialized by Swedish engineer Max Paabo in 1951. Weft thread is propelled using

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compressed air. It is simple operation with reduced mechanical parts and hence the maintenance cost is very low.

Fig. 5.2

The working principles of air jet weaving machines are based on carrying the yarn by the friction of the air jet. During the yarn’s forward movement by the air in the sheds, the velocity of the weft yarn decreases because of the decreasing pressure and the disturbance on the air flow direction. The air jet must provide a constant speed to the weft yarn along the weaving wideness. To preserve weaving defects and asynchronous beat-up movement, the weft yarn position and the instant velocity of the weft yarn must be fully controlled during the weaving process. Advantages of Air-Jet Weaving Machine: 

High productivity



High filling insertion system



Reduced hazard because of few moving parts



Low noise and vibration



Low spare parts requirements



To increase the production of loom by increasing the speed and by increasing the width of loom



Machines are versatile and roust to produces light to heavy value added fabric



Almost all loom motions are being controlled electronically



These looms can be operated up to 40 looms per operated



Fully automatic lubrication system



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In Arvind Shirting Division, they had 5 weaving divisions known as Classical-1 to Classical-5. They were using Toyota air jet looms both cam(max 8 harness) and dobby(16 harness). Warp Beams are first installed to the Air jet loom set, and then after a weft is entered into nozzles through air pressure. Warp is seen vertically on these machines and weft is horizontal to it. Weft enters through censors and passes the full lobby of warp and the dents of warp are set before starting the machine. Dents are defined as gap between two ends. The larger the dents the lesser will be the gap between two ends. Generally, one machine produces 500 meters of Raw Fabric daily depends on picks. In addition, to produce in such a hassle environment you need to have 75 to 80 % of humidity required in every textile mills and due to this 10% contraction of fabric takes place in weaving department. There is inflow of cool atmospheric air from above floor and outflow of air ventilation is given at underground level. There is air blower attached on the above of such machines to remove unwanted fibers on machines, which is continuously rotating for cleaning purpose. After one beam is over there is a need for knotting to have a continuous production for Raw Fabric and for that, this department is having a Knotting machine to join the next beam. There are indicators on each machine for the Terminologies such as T- Total Breakages W- Warp Damages F- Weft Breakages L- Leno and other Breakages. This indicators help operators in make out damages that occurs due to Dyeing and Sizing and sometimes due to weft also. Weft is procured from outside suppliers, so if there are more damages or breakages of weft then suppliers are to be aware and they will have to give more focus on these breakages.

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Due to hassle, working environment workers are given Earplugs and Masks due to humidity level. There are 100 workers in a shift and total there are 3 shifts and approximately 300 workers work in this department.

PROCESSING & FINISHING DEPARTMENT: Finishing of grey denim fabric normally carried out after weaving. It takes an important role in fabric properties, appearance, softness and residual fabric shrinkage. The main purposes of applying various finishes may be summarized as under.

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1. HIGH SALES APPEAL: To impart properties of attractive appearance, supple handle, softness and good drape. 2. HIGH WEAR QUALITY: This refers to adequate tensile and abrasion strengths, dimensional stability, crease recovery and freedom from pilling. 3. BODY PROTECTION AND COMFORT: This relates to proper heat insulation, moisture absorption and air permeability. 4. SPECIAL EFFECTS: These include water-repellency, reduced flammability, mildew and moth-proofing, anti-static behaviour and soil release property.

Classification of Finishes:Considering the existence of a large number and a great variety of the finishes for the cellulosic fibres, it is understandable that a completely satisfactory classification is not possible to make. The finishes are often sub-divided as physical and chemical, permanent and temporary, deposition and reactive etc. Sometimes the finishes are classified according to the effects obtained like appearance, wearing qualities, weighting etc. To complicate the matter further, the final folding and packing of the materials is sometimes included in the list. However the following description, though not perfect, is fairly rational and does justice to the topic. Physical /Mechanical Finishes:(a) TEMPORARY / NON PERMANENT (i)

Calendering: Swizzing, Friction, Chasing, Schreiner, Embossing and Felt

(ii)

Beetling

(b) DURABLE (i)

Raising, Sueding, (Emerising or Peach Finish)

(ii)

Shrinkage Control Finishes

Chemical Finishes:-

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(a) TEMPORARY / NON PERMANENT (i)

For Handle and Appearance: Softening, Stiffening, Weighting, Lustering (other than Mercerising)

(ii)

Special Effects: Water-Repellency, Flame-Retardancy, Mildew Proofing

(b) PERMANENT (i)

Crease Recovery, Softening

Water-Repellency, Flame-Retardancy, Mildew-Proofing In this department, first grey fabric is inspected and after that batching is done which simply means converting small rolls to big rolls. Batching is necessary because the fabric rolls cannot be fed to the machines in small rolls as it hinders production. Then after batching, it is sent for singeing and desizing. There were 2 such machines there running at an RPM of 100 and temperature varied between 960-1000C with an approx pickup of 72%. The liquor used for desizing consists of an sequestering agent (Lenitol DMCP;1 gpl), wetting agent (Lenitol ZD;5 gpl) and the enzyme(Biogreen;1.5 gpl). The stay timing was 1213 sec. Maximum roll length was 5000m and average production from these 2 machines was 35000m/shift. Then the roll is packed in plastic and kept for 8 hours (continuously rotating) for the enzymatic action to take place. After 8 hours, the roll is sent to Injecta Washer to remove the enzymes and washed with water at a speed of 70 m/min. Temperature inside the washer was kept near 90C. Avg production from this machine was 28000m-30000m per shift. After washing it is sent for mercerization. They had 3 machines for mercerization, 2 Beninger (one running at a speed of 35 m/min and the other at 60 m/min) and 1 Kyoto(running at 80 m/min). After mercerization, the fabric rolls were segregated according to the finish required (heat-set & non heat-set). If bleaching is required, then it fed to the continous bleaching range(CBR).

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Then they are sent to the stenter machines. They had 4 stenter machines (2 fo Montforts, 1 Montfong, 1 Montex). Approx. Pickup in these machines was 65% and they were running at 65-70m/min. After heat setting, they are sent to the curing machine for resin finish(optional). They were using 2 curing machines namely Montforts thermex. They also had 3 machines for Sanforization running at a speed of 62m/min and temperature was kept near about 140 C. After sanforization, if required the fabric roll is sent for a 3 bowl calendaring machine made by Ramisch Guarneri. The company also had 3 laufer machines for peach and carbonium finish.

INSPECTION & QUALITY ASSURANCE DEPARTMENT: Arvind is committed at providing the best quality of fabric to the consumers for over 80 years now. The quality control is an integrated process that starts when the customer gives the order, and the DNTG develops the samples accordingly, it is checked for quality assurance

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measures and compliances with customer needs. At later stages the fabric is inspected and testing of parameters of fabric is done. Essentially there are 2 major parts of quality assurance

quality Assuran ce Testing Physical Testing Chemical Testing

Inspection in process final

Shade testing Process Control shipment clearance certification and accreditation

Arvind follows 100 percent inspection procedures. The acceptance level of the fabric depends on the customer preferences. Inspection department uses 17 Kitamura Machine to find such defects in fabrics. The inspection frame is aligned at an angle between 45 and 60 degrees. Speed of fabric on inspection m/c: 25m/min Light of 100 Lux Inclination: 57

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There are two inspectors to keep continuous watch on fabric for finding the defects. The 4point grading system indicates that as per customer requirement defects are allowable upto their levels. 4-point grading system is used for inspection of fabrics and this includes:

Size of defect

Penalty Points

3” or less

1 Point

3” to 6”

2 Points

6” to 9”

3 Points

More than 9”

4 Points

Holes or Openings(Largest Dimension) 1” or less

2 Points

More than 1”

4 Points Table 7.1

No penalty points are recorded for minor defects. Major Defects are classified as follows:Major woven fabric defects such as slubs, holes, missing yarn, conspicuous yarn variation,end out, soiled yarn, and wrong yarn.- Major knitted fabric defects are mixed yarn, yarn variation, runner, needle line, barre, slub,hole, press off.- Major dye or printing defects are print out, dye spots, machine stop, color smear or shading. Points per 100 square yards = Total points scored in the roll x 3600 Fabric width in inches x Total yards inspected Fabric containing more than 40 points per 100 square yards is considered as SECONDS At the beginning of the month the inspection department gets the production plan for the entire month and they plan their procedures accordingly. The finishing department gives the material transfer note to the inspection department where the material is checked for the following defects: Bowing and Skewing Check for skewed, bowed and biased fabric. For this purpose check the bowing and s skewing at every 10 meters. P a g e | 36

The bowing and skewing are calculated as follows: Bow: A bow is an uneven deviation of a weft from a line drawn perpendicular to the selvedge of the fabric.

Skew is a straight line deviation of a weft from a line drawn perpendicular to the selvedgeof the fabric.

If the average Bowing or Skewing for a roll is more than 2-3%, reject the roll.

TESTING DEPARTMENT:

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The quality department and their testing procedures were accredited by Next, Ralph & Lauran, Levis, Mexx, Marks & Spencer, Debenhams, Nordstrom, Bureau Veritas, etc. The samples are tested for/by: 1. 2. 3. 4. 5.

Tensile Seam Strength: Titan Machine Tear strength : Elmatear Abrasion/Pilling : Martindle For Shrinkage change in temple marks are noticed after washing. Shade matching is done in a dark room using Verivide CAC 150, Gretagma C beth

Spectralight III. 6. To check the durability of resin finish, the fabric sample was repeatedly washed and the smoothness appearance (SA) is recorded. Maximum SA of cotton is 3.5. 7. Washing fastness: Gyrowash machine was used. Temperature varied from 40-48C. 8. Crocking fastness: Jamesheal crockmeter. 9. Light colorfastness: ATLAS XENOTEST 220. 10. Washing Machines: 2 electrolux front loading machines. & 6 top loading whirlpool machines. Minimum Tensile strength: 25 lbs

Minimum Tear Strength: 1.5 lbs

Minimum Shade change : >4

Minimum Staining : >3

Minimum Seam Slippage: 15 lbs

Minimum Dimensional Stability: