No:Trng
1. TEXTILE INDUSTRY IN INDIAIndustries have a major role to play in the economic development of underdeveloped countries. Textile industry is the one of the oldest industries existing till date. Although, initially this industry catered to the needs to cover the Human Beings, but its importance and significance groomed in Egyptian Civilization.
For the most of recorded history, mankind has relied on natural fabrics, particularly cotton, linen, wool and silk for textile products. In addition, the technology of fabric manufacture was relatively simple.
In India also, the textile industry revolved around these natural fibers spun and woven on handlooms. The production was mainly to cater to the parts. Gradually, India mastered in the textile industry and its textile products gained famed worldwide. It was only after industrial revolution in England, when machine substituted man and production started on large basis.
However, the demand could not grow up in the same proportion and India suffered due to unbalance between demand and supply, thus ultimately resulting in lower prices. However with the advent of industrial revolution, the textile industry in India begins to rise due to open government policies and import of technical know-how and machinery.
During the past few decades, the textile industry has gone through a period of unprecedented changes. The production of manmade fibers and their use in industry has surpassed that of natural fibers. The twentieth century customer has choice among linen, wool, rayon, silk, nylon, acrylic, polyester, etc. And also wide range of different blended fibers.
Today, the textile industry applies scientific parameters to optimize production so as to develop textile products to meet specific consumer needs and demands.Changing fashions and desire for better quality have boosted the textile industry in recent years. With increasing population, demand for fabric is rapidly increasing and new units are being established while the existing ones are going for mass expansion and modernization.
2. INTRODUCTION TO NAHAR GROUPNAHAR GROUP, established in 1949 with Oswal Woolen Mills, Ludhiana, surges a head in establish itself as a repudiated industrial conglomerate with a wide range from spinning, knitting, fabrics, hosiery, garments, soaps, vegetable oils and sugar.
2.1 NAHAR GROUP OF COMPANIES INCLUDES:
. .
Oswal Woolen Mills Limited.
Nahar Spinning Mills Limited.
Nahar Export Limited.
Nahar Industrial Enterprises Limited
Nahar International Limited
Nahar Sugar and Allied Industries Limited2.2 OSWAL WOLLEN MILLS LIMITED, (OWM)
OSWAL WOOLEN MILLS LTD is the Flagship Company of over US$500 millions NAHAR GROUP OF COMPANIESOswal Woolen Mills NAHAR GROUP, established in 1949 surges ahead to establish it self as a reputed industrial conglomerate with a wide ranging portfolio from Spinning, Knitting, Fabric, Hosiery GarmentsEtc.The group has spinning capacity of 0.4 millions cotton spindles 25000 worsted spindles with turn over of $500 million inclusive of export turnover of $150 million. Out of total production, 60% of the production is dedicated to exports and the rest 40% for domestic market. The production facility has been awarded ISO 9001:2000.
By spinning knitting yarns perfectly in keeping with global trends towards easy care, warmth & lively feels, OWM is leading the way in hosiery manufacturing, offering worsted dyed yarns, acro-wool, blended yarns, fancy yarns & wool polyamide combinations for velvety looks.Today OWM is the flagship company of the glorious Oswal Empire and a proud owner of widely loved Super Brands in Knitwear, Monte Carlo and Canterbury. The company boasts of a product range that is truly large and varied. They include diverse types of Woolen, Acrylic and Synthetic Blended Yarns, Lambs Wool Yarn, Woolens Viscose & Acrylic Tops, Textile Fabric, Woolens Knitwear, Hosiery & Cotton Garments.
The markets of NAHAR GROUP are cris crossed allover the globe with major clientele in Australia, New Zealand, Europe, Middle East, Africa, Russia and Asia. The objective is meeting the buyers expectations with consistent quality backed by R & D divisions equipped with latest equipment, Cream of highly qualified technocrats and adhering to timely schedules
2.3 NAHAR SPINNING MILLS LIMITEDNSM has installed capacity of 93408 spindles with total production of 13077 Metric ton of Cotton / Syntheticblended Yarn. The performance of the spinning division has shown upward trend vis--vis production and sale of Cotton Yarn and Synthetic Yarn.
The Company has 93408 spindles for the manufacture of Cotton / Synthetic & Blended Yarns. The company has also put up a Mercerizing cum Dyeing plant at village Lalru, Patiala for the manufacture of High Value Added Yarn, for the quality conscious market of U.S. & European Union. The capacity of the plant is 2040 M.T.The Garment Division contributed Rs. 133.73 crores towards the revenue of the company as against Rs 200.95 crores in the previous year. The lower allocation of quotas for the second half of the financial year adversely affected the performance of the segment. The stiff global competition coupled with demand shrinkage from overseas buyers also adversely affected the Exports as well as operating margins, resulting lower profits before tax at Rs. 4.38 crores as against Rs. 12.67 crores in the previous year.Expansion Plans: Keeping in view the emerging opportunities arising out of the quota free global trade w.e.f. 1st January 2005, the Management has decided to invest Rs. 112.45 crores in the capacity expansion. The company shall be putting up an Ultra Modern Spinning and Knitting cum Dyeing Plant with a capacity of 25000 spindles at village Lalru, Patiala. The expansion shall be financed by way of term loan of Rs. 80 crores from the Financial Institutions under Tuff scheme and balance form the internal accounts of the company. The management is quite optimistic that enhanced capacity will enable the company to improve its financial performance in the coming years.
Works:Industrial Area A, Ludhiana, (Punjab)
Dhandari Kalan, G.T.Road, Ludhiana (Punjab)
Village Simrai, Mandideep, Distt. Raisen (M.P.)Village Lalru, Distt. Patiala (Punjab)
Village Jalalpur, Distt. Patiala (Punjab)
2.4 NAHAR EXPORTS LTD.Back to the Future could be the title of NAHAR EXPORTS success story a dazzling satellite of NAHAR constellation. Starting out in 1988 as a manufactures and exporters of cotton hosiery garments the company soon realized that to strategically move backwards.
This, it did through focused backward integration by setting up its own spinning unit with an ambitious installed capacity of 25000 spindles aiming to provide premium value added and special yarns to the market. It was a conscious decision aiming to reap the benefits of the profitable merger. A proactive move strongly indicates the companys determination and confidence to race ahead of competition by superior utilization of both man and machines. A masterstroke towards optimizing administrative functional and legal hassles in one final swoop.
As an ISO 9002 company, NAHAR EXPORTS has two plants with a spindle age capacity of 1,45,000 spindles manufacturing a wide range of premium special and value added yarns manned by a dedicated workforce of 5000 exporting to enthusiast customers in competitive export market of Europe, Hong Kong, Singapore, Mauritius, South Eastern Asian Countries. NAHAR EXPORTS today is a major player in its chosen area blazing new trails and spinning new horizons in its on going pursuit of ever greater excellence.
2.5 NAHAR INDUSTRIAL ENTERPRISES LIMITEDEstablished in 1983 under the name of OSWAL FATS & OIL LTD. it underwent a total change over to become Nahar Industrial Enterprises a decade letter in 1994The company has to divisions under its umbrella namely, Oil & Soap Division and the textile division
The oil and soap division has two units. The fatty Acid unit is engaged in the manufacture of Fatty Acids Stearic Acid and Distilled Glycerin. The soap unit is engaged in the production of Toilet & Laundry Soap
In the textile division the company has two Spinning units and a weaving unit. The frost spinning unit, a100% EOU, is Engaged in the manufacture of cotton yarn is exporting its yarn to Europe, Hong Kong, Singapore Taiwan, Mauritius, Malaysia and Australia
The second unit, namely Sambhav Spinning Mills, is engaged in the manufacture of cotton yarn. The aggregate installed spindle in both the units is 38000 spindles. Nahar fabric the weaving unit is equipped with 176 Picanol Air Jet Weaving Machines (Cam/Repair/Dobby)
A weaving design studio backs the facilities where the time-tested handloom is used for product development activity in consonance with market needs
The preparatory is equipped with Benningers Warping & Sizing Machines. Inspection is equipped with automatic inspection with rolling machine from la Maccanica, Italy. Nahar fabrics has already produced more then 200 different constructions in Grey Fabric for in House needs and World Markets
Oswal Cotton Mills, established in 2000, has been clubbed with Nahar Fabrics and now, it is one of the most modern weaving and processing plant of India. There are two process house shortly named as P-1 & P-2.
2.6 NAHAR SUGAR and ALLIED INDUSTRIES LIMITEDEstablished in 1993 Nahar Spinning mills Ltd. associate companies in the assisted sector with PSIDC promoted Nahar Sugar
Nahar Sugar represents the Groups concerted thrust towards exploring new need based area in tune with the larger context of customer needs & market demands
The company has a modern sugar mill powered with the latest state-of-the-art equipment at district Fategarh Sahib, Punjab for producing all types & grades of sugar and allied products. The installed capacity of mill is 2500 TCDs
An active program of cane development to ensure regular cane supply to the plant is on. Also the power co-generated at the plant is being constructively used for capitative consumption to reduce the raw material cost.
2.7 MANAGEMENT OF NAHAR GROUPS. No.NamePost
1.Mr. Jawahar OswalChairman
2.Mr. Kamal OswalM.D.
3.Mr. S.S. BasuPresident
4.Mr. Dhawan SharmaH.O.D. (Tech. & Q.A.)
5.Mr. Anil TyagiH.O.D.(Finishing)
6.Mr. Arnav GoshHOD (Dyeing)
7.Mr. Amit WaliaH.O.D.(Bleaching)
8.Mr. Ravindra RohilaH.O.D.(PA & HR)
9.Mr. Sanjeev GulatiH.O.D.(Accounts)
10.Mr. Sachin JainPurchase Dept.
11.Mr. Vishnupal Bhatnagar.Folding Dept.
12.Mr. Gurpreet SinghP.P.C.
13.Mr. Naresh ChandSecurity Officer
3.
3.1 PLANT LAYOUT
PLANT LOCATION
1. Security office
2. Personal & Adm.
3. Manav vikas Kendra
4. Visitors waiting room
5. Accounts department
6. Workshop
7. Yarn dyeing plant
8. Boiler
9. Kitchen
10. Chemical lab
11. Physical lab
12. Finishing department
13. Folding and packing department
14. Grey checking
15. Store I
16. Bleaching department
17. Caustic recovery plant
18. Grey godown
19. Store II
20. Power plant
21. Pad dryer m/c
22. Pad steam m/c
23. Stenter m/c
24. Sanforisation m/c
25. Desize cum singe m/c
26. Scouring & bleaching continuous m/c
27. Mercerization m/c
28. Pitching m/c
3.2 ENTIRE PROCESS FLOWThe Customer and the Marketing department communicate with each other. The Marketing department then talks with Product Development Group (PDG) and then communicates the terms discussed to the Quality Assurance (Q A) and Product Planning and Control (PPC) who decides on the various guidelines and the time required to execute the order. These guidelines are then communicated to the Plant Head who communicates them to the various Departments according to the guidelines and instructions. The fabric is then sent to the Fabric Inspection and then to the Central Quality Assurance, who sent it to the Folding and Dispatch from where other financial activities follows.
Fig 3.1 Process flow4.
PRODUCTION PLANNINGANDCONTROLP.P.C. has a major role to play in the organizations. It creates the link between the production department and marketing department. It exchanges the information between both the departments.
(1) Role and Responsibility of P.P.C.
(a) Order Finalization: - The role of P.P.C. starts before the contract is executed and is in the stage of finalization. Marketing departments sends the sample to the P.P.C. department with the required delivery date. Then P.P.C. department sends the fabric construction to the fabric unit in the form of Enquiry Sheet. In the enquiry sheet expected, quality, quantity and delivery date is mentioned. Then the fabric unit sends back the enquiry sheet mentioning the availability of the quantity required and time taken against the same quantity. Then P.P.C. would inform to marketing concern head the actual delivery date.
(b) Making Lab. Dip: If specific colour sample is also sent, then P.P.C. would send the sample to the quality assurance departments. The Q.A. will make the similar samples (mostly it is 3) against the sample sent. These samples are added to the Card, which is known as Lab. Dip. (3 Lab. dip) and spends it to the P.P.C. P.P.C. will forward the same Lab. Dip. To the marketing concern head and out of the samples the buyer approves send one of them. After approval of sample contract is signed b/w buyer and the seller.
(2)Production planning and control: - The contract is send to the PPC department. Then P.P.C. plans the production against the contract send. Contract number is clearly mentioned on the contract. Contract has the exact quantity, quality, delivery date and rates. After Which the M.D. PPC signs will first make the folio and add it to the concerned marketing head folio file. Then production programme is made for the entire four departments. Production programme is a very important report which has the full information of the fabric to be processed. Following things are mentioned in the production programme.
Date of execution of the contract
Delivery date
Quality No.
Construction
Weave
Quantity
Packing Institutions
Shade No.
Shade
Finish
Contract No.
P.P.C. No.
Lot No.
Lot Number is a number given against the contract number only against this number, grey fabric can be issued. To get the grey fabric issued from the store Lot Number is required. P.P.C. number is the reference number against the particular contract.
(3) Lot Card: Lot card is again a very important document for the production department. The following things are mentioned.
Lot No.
P.P.C. No.
Grey Information (Sort No., construction, finish width, weight, supplier name)
Product Information (Shade No. Length in Mtrs.)
Customer Information (Party Name, Ordered Qty., Delivery Date, Order Quality, No. Of shade).
Process Information (Planned date. Delivered Date. Process steps, article no.)
P.O No.: -P.O number defines the process route of the fabric. The article no. has 7 digits and each digit has its own meaning.
Last three digits define the process steps.
Table 4.11234
FABRIC GROUPFABRIC TYPE CHEMICAL USCHANICAL
1.Bottom WTWhite Soft Peach
2.ShirtingNatural Stiff Normal
3.CottonDYEDPerfume
4.COT/Poly DYED PC RFD finish
5.LYCRA
6.Others.
(4)Complaint Handling: Complaint from the party against the contract is also handled by the PPC. To trace back the Bale No. is taken from the partly and send to the folding department. Folding department will find out the lot number and roll number against the Bale No. Then from the inspection report which is on 4 point system, the point given is checked. If the complaint is genuine then compensation is send against the particular complaint.
5.
HOD: Mr. AMIT WALIA
5.1 INTRODUCTIONThe grey fabric consists of various kinds of impurities like vegetable matter, waxes etc. In this section all of these impurities are removed and whiteness in fabric is imparted.Bleaching section consists of four sections from gray opening to mercerization. GREY SECTION
SINGEING AND DESIZING
BLEACHING AND SCOURING (PTR)
MERCERIZATION
Fig.5.1 PROCESS FLOW DIAGRAM:
5.2 GREY CHECKINGIn this section, the bales of grey goods are opened and are converted in the form of roles of required length and then sorting is done that is sort no. is given
Ex 2022116.
First and 2nd digit-Count of fabric(20)
Third digit
-Weave
i.e.
0.Dobby design
1. For plain
2. Twill
3. Drill
4. Satin
4th digit
-ply of yarn
5th digit
-type of loom
6th and 7th digit-serial no. of weaving unit.5.3 SINGEING AND DESIZING
INTRODUCTION
These two pretreatments are given in one machine. Firstly fabric gets singed and then continuously passed through desizing bath.
SINGEING
It is a process in which protruding fibers on the surface of fabric are burnt. The fabric is passed over a flame at high speed to obtain a smooth surface; the gas used is L.P.G. for burning purpose.
DIFFERENT SETTINGS OF THE GAS SINGEING M/C: 1. Speed of the Cloth: This may be varied with the help of differential gears provided. This is changed according to the GSM of the fabric.2. Height of the flame: This can be varied with the help of the valve provided at the side of the machine i.e. by changing the pressure of gas of the burner. This can be change when more heat is to be provided to the fabric i.e. when fabric is heavier in weight and its speed cannot reduce below a level.
3. Length of the flame: This can be varied with the help of the valve provided at the side of the machine. This can be change when the width of the cloth is more or less than the width of the flame.IMPROVED PROPERTIES Improved luster.
Minimized pilling tendency. Smoothens the fabric and improves the feel of the fabric.
DESIZING
It is the removal of size material from the grey fabric. Sizing is done to provide strength to cotton warp to meet the requirement of weaving. But this sized layer is to be removed before wet processing as it reduces the absorbing power of the fabric. Here enzymatic steep method is used for desizing because it is effective for ecology and quality of desizing. The starch is degraded as:
Fig 5.2 Degradation of starchBasis parameters which affect the activity of the enzyme are following:
TEMPERATURE.
pH
Time of Contact( IMPREGNATION )
Fig 5.3 PROCESS FLOW OF SINGEING AND DESIZING Table 5.1: SINGEING PARAMETERSMACHINE MAKEOsthoff Senge, Germany
MODEL NAME42327WUPPERTAL
SOURCE OF FLAMEMixture of Gas & Air(75:25)
NO. OF BURNERS2
GAS PRESSURE12-13m bar
MAXIMUM SPEED OF FABRIC100 mt/min.
FLAME HEIGHT2.5 inch to 4.5 inch (according to quality)
NO. OF BRUSHING UNITS2
Table 5.2: RECIPE FOR ENZYME DESIZING
ENZYME5 g/l
WETTING AGENT5 g/l
CHILATING AGENT3 g/l
Table 5.3 DESIZING PARAMETERS
CAPACITY OF DESIZE BATH750 lt.
TEMP75oC
NIP PRESSURE2 bar
ENZYME USEDBIOAOURLASE (OM Logistic Ltd.)
WETTING AGENT USEDLenetol CBRD (CRODA Chemicals Ind.)
CHILLATING AGENT USEDIntox (CLARIANT Chemicals Ind.)
% EXPRESSION100%
5.4 CONTINUOUS PRE TREATEMENT RANGE
The fabric from batch (after storing for 8-12 hrs) is continuously processed for following processes- Desize wash, combined scour-bleach, Washing, Neutralization, and Drying.
DESIZE WASHER
INTRODUCTIONThe action of enzyme hydrolyses the starch into soluble degradation products. They are removed completely before further processes on the INJECTA unit by the action of steam & water jets then hot wash at 95OC is given to the fabric in the EXTRACTA unit.
Fig 5.4 PROCESS FLOW IN DESIZE WASHER
INJECTA: The Desize module of INJECTA is exclusively used to wash the fabric. With the INJECTA, the intensive washing system, all types of size from PVA to starch are removed without preswelling. Other relevant advantages are small space requirement and minimum water consumption.Technical Data:
1. Temperature -
100 C
2. Degree of Humidity Humidity at the in feed end
:60 70% or Dry.Humidity at delivery (depend on fabric):Max 130%.
3. Utilities
Water
:400 l/m.
Saturated Steam
:4.5 bar.
Compressed Air
:7 bar.
EXTRACTA:
It is used to wash the fabric using counter current flow of water. The high Washing effect of this machine is achieved through exact liquor segregation and counter-flow guidance. It has been designed for especially low power and water consumption.
Temperature -
Maximum washing temperature: 95 C.
Heat up time (approx.)
:10 min.
Utilities -
Maximum water consumption:4 to 8 ltr per kg.
(Direct heating)
Steam pressure
:4 5 bar.
Fig 5.4
PRETREATMENT RANGE
It is a combined process in which Scouring and Bleaching is done. In this process we remove natural as well as added impurities of essentially hydrophobic character like oils, fats, waxes etc. As completely as possible and leave the fabric in a highly absorptive condition without undergoing significant chemical or physical change or damage and also for removing the natural coloring matter of cotton to give the fabric a white effect. This white effect is essential for the dyeing process especially for the light or medium shades.
The natural impurities & natural coloring matter can be destroyed by this combined process. Table 5.4 Chemical used in Pre Treatment Range:-
Tank NO.Chemicals
1.H2O2
2.NaOH
3.CBRD
4.Intox
5.Lanitol CESE
Function of chemicals:-
H2O2- Universal Bleaching Agent
This liberates nascent oxygen which is responsible for the bleaching action.
CBRD- Wetting Agent
The surface tension of water prevents the wetting of hydrophobic material and it is therefore necessary to reduce it to enable fabric to be wetted easily. For removal of impurities during scouring it is necessary to incorporate a wetting agent or surface active agent.
NaOH- Conversion of glycerides of fatty acids into soap by the use of NaOH is called SAPONIFICATION. Thus the oils and fats in the cotton textile are saponified during the scouring process into water soluble products.
One more important function of NaOH in the semi-bleach or combined process is to activate
H2O2 it liberates nascent oxygen because of which bleaching is done in the CONTINUOUS PROCESS.
INTOX- Sequristing Agent
A sequristing agent can Chelate (combine to form complex with) the metallic ions in water and also reduce the hardness of water. These agents can replace the use of Sodium Silicate and Sodium Hexa-meta phosphate to some extent.
Lanitol CESE- Stabliser
This is to control the rapid decomposition of the peroxide when alkali is added in the solution i.e. to ensure a fairly uniform availability of the per hydroxyl ion for the bleaching action stabiliser are used.
Fig 5.4 PROCESS FLOW IN BENNINGER PRETREATMENT RANGE:-
Table 5.5 RECIPEH2O230 40 ml/kg
SEQUSTRANT2 ml/kg
WETTING AGENT3 ml/kg
STABILIZER7 - 10 ml/kg
NaOH27 30 ml/kg
5.5 IMPECTA UNIT
The impregnation module contains only a small volume of liquor, impregnation fabric under high turbulence & high temperature with minimum amount of liquor.
The chemicals are injected by force. Water is added continuously. Water supply is controlled by level regulation.
The amount of chemicals can be varied between normal impregnation & high wet pick up impregnation via the adjustable squeeze roller.
The displacer with the guide roller guides the fabric into the liquor. The level is determined by the weight of the floater in the liquor by the level sensor.
Temperature: Maximum treatment temperature = 60 C.
Moisture content:
At in feed end =60-70%.
At deliver end =max 130%.
REACTA (STEAMER):
The chemicals applied to the fabric react in the steamer according to the specific process .the steamer can provide tight strand fabric guidance or place the fabric on the roller bed for stationary dwell time of up to 60 min .the automatic and regulating station guarantees consistent and air free contestation .
Temperature:
Maximum treatment temperature=98 C.
Heat up time
=30 min.
Various ways of passing fabric through steamer:
1. Short time steamer with reaction , cloth content = 25-200mt.2. Steamer with single roller bed, reaction time = 3-40 min.
3. Combination steamer with single roller bed, reaction time = 3-45min. This type is used in the NIEL Fabric Unit-2 Fig 5.6 4. Combination steamer with double roller bed, reaction time = 5-60min
5.6 FORTRACTA:
Purpose: it is used for:-
1. washing
2. Even batching guides fabric properly.
3. Avoid any creasing in the fabric.
Temperature:Maximum treatment temperature = 100 C.
Moisture content:
At in feed end =60-70%.
At deliver end =max 130%.
EXTRACTA WASHER:
There are four washing chambers based on counter current washing principle.
Neutralization:
When the mercerization is not required then neutralization is done in forth washer.
If mercerization is done then no there is no need of neutralization.
Fortracta
Extracta washer Neutralization Vertical Drying Range Exit J-scray
Fig 5.7CYLINDER DRYING MACHINE
The bleached fabric in wet condition is dried on to the cylindrical drying range. This is a vertical drying range with 30 cylinders.
Functions: - Function of this machine is to dry the fabric after various chemical Processes like bleaching, dyeing etc. whose final product is wet fabric.
Features: -
The machine is based on the principle of high temp steam hating. The drying Range consists of no. of mangle rollers which removes approximately 70% of water from the fabric. It consists of a bow shaped roller to remove crease from the fabric.
There are 30 cylinders arranged vertically and heated by steam vapourize water from the fabric. Starting four rollers are coated with a paint to give initially normal heating so that Face to back effect can be avoided. One motor drives all the hot cylinders through belt. Another separate motor is provided for driving 3 cooling cylinders. Chilled water is circulated through the cooling cylinders. There is a length measuring cylinder. There are two exhaust fans for exhausting the humid air at the upper side, driven by two motors.
Steam pressure
:2.5 5 kg/sq. cm
Temp of the machine : 120-150 C.
Speed of fabric
: 60-65 mt/min (for suiting).
80 mt/min (for shirting).
Fig 5.85.7 MERCERISATION
Impregnation of wet or dry fabric in caustic soda solution of determined concentration under tension is the process called mercerization.
OBJECTIVES OF MERCERIZATION
1. Improve Luster2. Provide Dimensional Stability
3. Increase Absorbency
4. Increase Dye-ability
5. Reduction in Convolutions
Fig 5.9 PROCESS FLOW IN BENNINGER MERCIRISER
VARIOUS UNITS IN MERCERIZATION:BEN DIUSNSA:-
Its function is to accumulate the fabric in J-Scray when batch changing has to be done
PRE WETTING SECTION:-
First the fabric is passes through the water and then fabric passes through the pre wetting trough containing week lye (alkali of 10 Be) , this improves the initial absorbency of fabric .
IMPREGATION ZONE:-
Fabric passes through strong alkali solution with following specifications
Strength of caustic=29 Be.
Temperature
=60 C.
Passage length
=14 m.
NOTE: - 1 Be (Bauus)=1.4 Tw=6 gpl
=0.59%.
DWELLING ZONE:-
This is used to give required dwell time after impregnation by passing through the cylinders
(Passage length= 32 m.). After the fabric is squeezed.
STENTRING ZONE (chain with pin):-
Its object is to stretch the fabric to provide required tension.
EXTRACTA WASHERS:-
There are six washers. Initial four washers for the hot washing of the fabric and fifth washer is for neutralization and sixth again for washing.
5.8 PEACHING
Peaching is a process of developing very low pile on the surface of fabric. Peaching of fabric is done by using emerising or brushing system depends on quality & construction of fabric, effect required by customer etc. In Nahar Group there are machines of both type of mechanism.
Caru (emerizing system) 1
Gematex (emerizing system) 2
Lafer (Brushing system) 1
GEMATEX:
MADE : GEMATEX (GERMANY)
NO. OF PILE ROLLS : 12
NO. OF COUNTER PILE ROLES : 12
DIRECTIONS OF PILE ROLES : IN THE DIRECTION OF RUNNING FABRIC
DIRECTION OF COUNTER PILE ROLES: IN THE DIRECTION OPP. TO RUNNING FABRIC.
ENERGY OF PILE ROLES: 50 200 (DEPENDS ON EFFECT REQUIRED AND QUANTITY)
ENERGY OF CP ROLES: 50 200 (DEPENDS ON EFFECT REQUIRED AND QUANTITY)
EMERY OF PILR ROLES : 220 GRIT
EMERY OF CP ROLES : 100 GRIT
RPM OF DRUM : 90 110
In this machine, required effect we can change energy of pile and counter pile roles, rpm of drum, speed of machine & tension of fabric on emery drum.
6
HOD: Mr. ARNAV GHOSH6.1 INTRODUCTION
Dyeing is defined as the application of dye to fibers (according to their affinity) to have desired colour. Every natural or synthetic fiber varies in affinity or capacity to take the dyestuffs.
In Nahar Fabrics, dyeing is done at fabric stage. Main types of fabrics those are dyed are:
1) 100% cotton fabric
2) P/C blend.
3) Lycra (less quantity)MACHINERY IN DYEING
1) PAD-DRY
2) PAD-STEAM
Fig 6.1 PROCESS FLOW ON PAD DRY:-
Fig 6.1 PAD DRY IN NAHAR PROCESSING UNIT-2(VIEW FROM EXIT END)VARIOUS UNITS IN PAD DRY1. Batch of fabric:- Batch of fabric2. Tensioning guides: - To give proper passage and tension to the fabric.
3. Entry J-scary: - To facilitate continuous process while batch changing has to be done.
4. E+L guide: - To guide the fabric by guiding the selvedge.5. Brushing unit: - It consists of two brushing roller. This is provided to remove fluffs from the peached fabric. Brushing efficiency can be changed according to requirement by changing the position of side handle
6. Exhaust fan: - From the other side of brushing roller a motor driven fan is provided for exhausting the waste and collecting it in to separate bags.
7. Cooling cylinders: - To maintain uniform temperature which facilitate in uniform pickup of dye liquor.
8. Kuster mangle: - Fabric is passed through the Padding mangle where the colour padding takes place. It is jacketed by chilled water line to maintain its temperature.
* 2 dip 2 nips.
* Differential pressure along left, middle and right portion of fabric.
Fig 6.29. Ring device: - There are 11 guide rollers to give time for airing.
10. IR-pre heater: - The cloth is passed through Infra red unit where 50-60% fabric is dried with the help of infrared rays. Gas and air mixture is supplied to burners from MAXON GAS STATION to produce IR rays. The temperature inside is around 750c.11. Drying chambers:-
Further the fabric is passed through 3 heating chambers. These heating chambers are heated with the help of furnace oil and heat is exhausted with the help of fans in it. The temperature of the chambers depends on the type of fabrics. The temperature in these chambers is maintained somewhere around 140-180 degrees (for thermosol dyeing) and 100-130 degrees (for other methods).
The time for drying /thermosoling depends upon the speed of the fabric which in turn depends upon quality of fabric (GLM).
For light weight fabric high speed, lees time for drying and also lower IR temperature, drying temperature and fan% while higher exhaust%.
PLEVA (Sensor):- Attached outside the chamber in each hot flue chamber used to control humidity in the case of E-control process
12. The fabric is passed over cooling cylinder.
13. Exit J-scary: - To facilitate the continuous process while batch changing has to be done.
14. E+L guide: - To guide the fabric by guiding the selvedge15. Length measuring roller and antis tats are also provided
Then the fabric is rolled on the rolling beam with the moisture content of 2-3%.
Further the fabric is sent for colour fixation and developing.
Fig 6.2 PROCESS FLOW ON PAD STEAMER:-
6.2 VARIOUS UNITS IN PAD STEAM1. Batch of fabric.
2. Tensioning guides:-
To give proper passage and the tension to the fabric.
3. Entry J-scary:-
To facilitate continuous process while batch changing has to be done.
4. E+L guide & length measuring roller:-
To guide the fabric by guiding the selvedge.
5. BICOFLEX Padder:-
The fabric is passed through hydro and caustic for vat development and for reactive dye, fabric passed through alkali solution and 60% chemical pickup takes place.
Temperature of padding bath is 35-40 C.Normally tried to be done at room temperature.
Even pressure throughout the width of the fabric.6. REACTA:-The fabric is then passed through steam chambers here the chemical reaction takes a dwelling time of one minute and dyes enter the fabric completely.
Various features of Reacta:-
1. Horizontal or vertical fabric entry with heated lips and exhaust fan for excess steam.
2. Section with 25 m fabric content.
3. Large fabric diameters (193 mm) for creaseless fabric runs.
4. Lifetime lubricated bearings.5. Top rollers individually driven by AC motors.
6. Load cell to measure fabric tension for drive control.
7. Roof heating.8. Water seal with small liquor content and uniform liquor distribution. In water seal continuous chilled water is circulated through the jacket, which facilitates in the removal of condensed steam.
9. Temperature or volume controlled fresh water flow to the water seal.
10. Steam conditioning unit.
11. Probe to measure steam condition.
12. Automatic cleaning system.
Fig 6.37. Washing unit:-
Washer-1&2 having water temp. 40 C used for cold washing.
Washer-3, 4&5 are used for vat development (H2O2) or simple hot washing/soaping for reactive dyed/white fabric.
Za Washer- 6&7 are used for soaping.
Washer-8 for hot washing.
Washer-9 for neutralization and washing both in the same chambers.
As this machine is inclined in position from backward side so it uses less water as washed fabric comes in contact with the fabric first then it goes to the other section.ie water flows from washer-9 to washer-1.8. Vertical drying range:-
The dyed fabric in wet condition is dried on to the cylindrical drying range. This is a vertical drying range with 33cylinders.
9. Cooling cylinders:-The fabric is passed over cooling cylinder.
10. Exit J-scary: - To facilitate continuous process while batch changing has to be done.
11. E+L guide:- To guide the fabric by guiding the selvedge
12. Batching or Trolley: - Finally fabric is batched or collected in trolley.
6.3 VARIOUS METHODS OF DYEING:-
1. PDPS for vat dye on 100% cotton.2. PDPS for reactive dye on 100% cotton.
3. E-CONTROL.
4. THERMOSOL/PDPS vat (PET/Cotton).
5. THERMOSOL/PDPS reactive (PET/Cotton).
6. THERMOSOL/E-CONTROL (PET/Cotton)
1. PDPS for vat dye on 100% cotton
Fig 6.4 Process flow diagram of PDPS Vat Dye on 100% COTTON
2. PDPS for reactive dye on 100% cotton.
Process flow diagram of PDPS Reactive Dye on 100% COTTON
3. E-CONTROL Reactive Dyeing Process
Basic principle of E-control process.The E-Control process comprises just 3 steps: Application of dye, Drying, and
Washing off. The dyeing system must be carefully balanced to ensure complete fixation of the Remazol or Levafix dyes within the drying time.
However, complete fixation of reactive dyes is not possible in normal drying conditions because of the wet bulb temperature, which is a characteristic of all convection-based drying systems. It means that during drying, the temperature of the moist goods is far lower than the surrounding temperature
In normal drying processes the temperature on the goods can drop to 50-55C. The exact temperature depends on the humidity of the air used to dry the goods. If humidity is 25% and the air temperature is 120C, the temperature on the surface of the goods is around 68C. If humidity is 30%, the temperature on the goods is around 71C.
The E-control process uses this physical fact to fix the reactive dye during drying. Three key variables time, temperature and humidity are used to ensure accurate control of the dyeing process in the Thermex hot flue.
6.4 RECOMMENDED DYES, AUXILIARIES AND ALKALI SYSTEMS
Evidently, the dyes used in the E-control process have to be suitable for the process conditions. Since dyeing is completed in approximate 2-3 minutes, reactive dyes with high to medium reactivity are particularly suitable. All Levafix and most Remazol dyes can be used.
In practice, Levafix dyes are used for pale to medium shades, while Remazol dyes are used for medium to very deep shades.
Soda ash or soda ash/NaOH is normally used as the alkali system. To ensure optimum reliability, it is essential to dose the alkali and dye solutions separately. For example, the following amounts of alkali are recommended for LevafixCA dyes: Table 6.1Amount of dye Up to 10 gpl >10-30gpl > 30 gpl
Soda ash 202020
NaOH 50% -2 ml/ltr4 ml/ltr
Common auxiliaries used in continuous dyeing processes can be used, e.g. wetting agents, antimigration agents and, if necessary, sequestering agents.
A mild oxidant can be added to prevent reduction of the dyes. Urea is not essential for the E-control process but up to 50 g/l may be advantageous in same circumstances.
Features of the E-control process
E-control process does not use a separate fixation step. By contrast, all other continuous dyeing processes require separate fixation of same sort. The E-control process requires 35% less time. The process also has a logistical benefit: since the goods are dry at the end of the E-control dyeing process, they do not have to be washed off immediately and can be stored without problem. E-control can be used to dye all shades that can be obtained with reactive dyes. That includes brilliant turquoise, deep Bordeaux, deep navy and, of course, black.Energy and chemical requirements The E-control process needs far less energy than the e.g. PDPS process because it cuts out the extra fixation step (steaming).
For chemicals, unlike the PDPS process, the E-control process does not require any salt.
The amount of alkali is similar.Limitation
Nevertheless, like all dyeing processes, E-control does have its limitations:
The first is that Indanthrene dyes can be dried by using the Thermex hot flue but not fixed as an air free steamer is required for this. Pale to medium shades can be dyed on PES/COTTON blends using a modified one-bath TTN process but a separate thermosol step is required after the E-control step. Consequently, at least two Thermex chambers are required. More experience is needed to obtain reproducible dyeing on very lightweight qualities (
