Industrial
April 6, 2017 | Author: Tauhidul Islam Rajib | Category: N/A
Short Description
attatchment...
Description
Knowledge for Innovation and Change
Department of Textile Engineering
Industrial Attachment (8th February to 8th April)
At NRG Composite Yarn Dyeing Ltd Jamirdia, Masterbari, Valukla Mymensingh, Bangladesh.
Prepared by Name
ID
Batch
MD. Tauhidul Islam
BTX-120200212
9th
Supervisor: Prof. Dr. M. A. Jalil Head Department of Textile Engineering Northern University Bangladesh
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N.R. Group
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In the name of GOD The most BENEFICIENT The most MARCIFUL
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Knowledge for Innovation and Change
Department of Textile Engineering
Name & Designation of Supervising Teacher Prof. Dr. M. A. Jalil Head Department of Textile Engineering
Northern University Bangladesh Cell No.: 01711269630
Name & Designation of Supervising Officer of the Mill MD. Akhtaruzzaman (Asstt. General Manager, Dyeing) NRG Composite Yarn Dyeing Ltd. Cell No.: 01710892942
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Letter of Transmittal To, Prof. Dr. M. A. Jalil Head Department of Textile Engineering Northern University Bangladesh.
Subject: Submission of the “Industrial attachment Report”. Dear Sir, I am pleased to submit my “Industrial attachment Report” This is submitted under the program of B.Sc. in Textile Engineering in Northern University Bangladesh. The Report has been completed in accordance with the knowledge that I have gathered during my Industrial Training and the guidelines received from my honorable teachers. I tried to make this Report is to give a clear picture on Wet processing Technology practically used on “NRG Composite Yarn Dyeing Ltd.” However, I will always be ready to provide any further clarification that you may require. I, therefore, request and expect that, you will appreciate me with any sort of recommendation & valued suggestion & will cordially receive this Industrial Attachment for your kind assessment.
Sincerely Yours
Md. Tauhidul Islam ID: BTX 120200212 Batch: 8th, Sec: WPT Department of Textile Engineering Northern University Bangladesh 5
Department of Textile Engineering
Supervising Faculty’s Approval
…………………………………………… Prof. Dr. M. A. Jalil Head Department of Textile Engineering Northern University Bangladesh Banani, Dhaka
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Supervising Mill Authority’s Approval
…………………………………………… MD. Akhtaruzzaman Assistant General Manager NRG Composite Yarn Dyeing Ltd. Jamirdia Masterbari, Valuka Mymensingh, Bangladesh 7
DEDICATED TO MY PARENTS AND THE RESPECTED TEACHERS WHO ALWAYS TRY TO FIND WAYS AND THINKS TO PROVIDE WHICH I DO NOT KNOW AND DON’T HAVE
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Abstract
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Textile technology education is based on industrial ground. Theoretical background is not sufficient so, industrial training is an essential part of study to make a technologist technically sound in this field. Industrial training provides us that opportunity to gather practical knowledge. NRG Composite Yarn Dyeing Ltd. is a truly integrated undertaking. The textile division has the capability to offer a complete product range for the export & domestic textile markets. The goal of this textile factory is to become the preferred partner for sourcing high quality fabrics & clothing from Bangladesh. With highly advanced technology & an emphasis on developing local human resources, the textile division has the potential to make an important contribution to the nation’s growing readymade garments export sector. The rationale behind the existing structure & future expansion of the textile division is to capture value added at each stage of the textile manufacturing process. Despite Bangladesh’s lack of indigenous cotton production capability, NRG Composite Yarn Dyeing Ltd has leveraged Bangladesh’s labor cost advantage & export competitiveness to maximum level.
Acknowledgement
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All the praises are for the almighty, Allah who bestowed us with the ability and potential to complete this Internship. I also pay my gratitude to the Al-mighty for enabling me to complete this Internship Report within due course of time. Project paper is an academic function of the Northern University. We are highly delighted to express our regards & gratitude to honorable Professor supervising teacher: Prof. Dr. M. A. Jalil for providing us the chance to complete our internship and completion our project work in NRG Composite Yarn Dyeing Limited. We take this opportunity to record my deep sense of gratitude and appreciation to our Project Advisor “Md. Tanjim Hossain” (Lecturer & co-ordinator) Department of Textile engineering, Northern University for his constant encouragement and inspiring guidance with his wisdom. We also take the opportunity to express our sincerest gratitude to the management, administration & personnel of NRG Composite Yarn Dyeing Limited for their kind assistance. Cordial thanks goes Md.Akhtaruzzaman (Assistant General Manager) NRG Composite Yarn Dyeing Limited for their excellent co-operation during the period of our training. We would also like to thank Mushfikur Rahim Executive, knit Fabrics dyeing section for his sincere support. Above all, we would like to acknowledge our deep debt to all teachers of our university & particularly of Wet Processing Department for their kind inspiration & help, which remain as the backdrop of all our efforts. Finally, we would like to acknowledge that we remain responsible for the in-adequacies & errors, which doubtless remain in the following report.
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Content Summary
Chapter No.
Chapter Name
Page Range
01
Organizational Overview
02
Project Description
15-19
03
Man Power Management
20-25
04
Raw Materials
25-44
05
Literature Review
45-56
06
Chemical Laboratory
46-82
07
Production Planning Sequence Operations
83-115
08
Quality Assurance Department (QAD)
115-153
09
Effluent Treatment Plant (ETP) & Caustic Recovery Plant (CRP)
154-162
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Maintenance
163-171
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Utility Services
172-175
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Store & Inventory Control
176-178
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Conclusion
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12-14
Chapter-1 Organizational Overview
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Introduction: From fiber to fabric, the Textile division of N.R GROUP is a truly integrated undertaking. The Textile Division has the capability to offer a complete product range for the export textile markets. The goal of the Textile Division is to become the preferred partner for sourcing high quality fabrics and clothing from Bangladesh. With this goal NRG Composite Yarn Dyeing Ltd. is advancement of this journey. With highly advanced technology and an emphasis on developing local human resources, the Textile Division has the potential to make an important contribution to the nation's growing readymade garments export sector keeping green environment into close consideration. The ration behind the existing structure and future expansion of the Textile Division is to capture value-added at each stage of the textile manufacturing process. Despite lack of indigenous cotton production capability of Bangladesh, N.R Group has leveraged labor of Bangladesh cost advantage and export competitiveness to the maximum. Journey of N.R GROUP:
N.R GROUP today symbolizes a name a state of mind. But its journey to the growth and prosperity has been no bed of roses. NRG is proud of its exceptional staff and team members. Managing director and CEO of the group is a hand on leader, engaged in planning, directing and executing from production to marketing. His 35 years of experience in knitwear, sweater, yarn manufacturing and trading and his global networks is an asset to the company. The dynamic leadership of the managing director motivates the group to achieve increasing targets of turnover and diversify in to new ventures. In recognition of his outstanding contribution in business and export, the Government of Bangladesh has declared him a Commercially Important Person (CIP) since 1992. NRG’s executives bring to the company a wealth of experience, professionalism and areas of expertise from all over the world. The Group also employs foreign technicians and professionals to achieve perfection in the fields of yarn manufacturing, ribbon production, knitting, dyeing, sales and product development and quality control.
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Vision: To establish as a one stop source for the Global Knit Apparel market and to satisfy and meet customer's expectation by developing and providing products and services on time, which offer value in terms of Quality, Price, Safety & Environmental impact. Assuring complete compliance with the international quality standards and also providing the employees internationally acceptable working condition and standards. To promote the development and to use human talent & equal opportunity of employment NRG Composite Yarn Dyeing Ltd. procure the most advanced & sophisticated technology suitable for producing desired product and attain highest level of competence through continuous development of the professional management system and to ensure complete transparency in all aspect of business.
Mission: N.R GROUP realizes the need to stake out a competitive segment in the changing global market of today through technological excellence and human expertise. N.R Group is committed to transpose its local success to the world scene.
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Chapter-2 Project Description
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Name of the Factory: NRG Composite Yarn Dyeing Limited
Type: Knit fabric manufacturing for 100% export oriented readymade Garments Industry.
Year of Establishment: 2001, Commencement of Production in June 2002
Address: It is situated in Jamirdia, Master Bari, Valuka, Mymensingh, Bangladesh.
History of Project Development: In 1997, N.R Group entered the textile sector with its manufacturing facilities of cotton yarn. Combining modern technology with skilled manpower under N.R Group's unique inspiring, atmosphere, this new N.R Group venture soon rose to the top of the local textile industry. Today it has one of the most sophisticated vertically integrated set-ups. In 1998: Second unit of N.R Group established. In 2000: N.R Group Spinning Ltd. started its journey. In 2001: N.R Group Knit Fabrics ltd. and NRG Composite Yarn Dyeing Ltd. established. In 2002: N.R Group Knit Fabrics commenced with its production.
Textile Mills of N.R Group Group: N.R Group Knit Fabrics Ltd. N.R Group Spinning Ltd. N.R Group Textiles Ltd. NRG Composite Yarn Dyeing Ltd. N.R Group Multi Fabrics Ltd.
Physical Infrastructure:
N.R Group at Valuka have two shades. They are N.R Group Knit Fabrics Limited, NRG Composite Yarn Dyeing Total factory area is 165,000 ft Production space is 135,000 ft, single storied. There are four dormitories for worker, two dormitories for officials.
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NRG Composite Yarn Dyeing Ltd. maintains its telecommunication with VOIP connection to its different corporate zones, PABX connections and LAN connections. It’s others facilities areOwn Network Server, Own power management; Own utility management, Free transport facility, 24 – hour medical center, Fire service facility and ETP (Effluent Treatment Plant)
Different Departments: NRG Composite Yarn Dyeing Ltd has the following departments approximately:
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Product Type:
Piece Dyed fabric, Mercerized & Dyed fabric, Yarn dyed fabric, Mercerized yarn dyed fabric (double mercerized).
Product Mix:
Cotton: Carded, Combed, Compact, & Organic. Viscose: Modal, Mélange, Polyester, Lycra, Polyester-cotton blend, CVC
Product Range:
Engineering stripe and semi jacquard, Plain (100% cotton single jersey, slub single jersey, lycra single jersey. Pique (100% cotton, 100% Lycra), Four Needle structure, Wofel rib, 1X1 Rib (cotton), 1X1 Rib (lycra), 1X1 Rib (slub), 2X2 Rib (100% cotton), 2X2 Rib (100% Lycra), 2X1 Rib, 4X4 Rib, Interlock, Pique interlock (pima cotton), Interlock (double mercerized), Locust, Jacquard, Fleece & Terry fleece, etc.
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Capacity: Around 15,000-17,000 Kg. of Knit fabric processed per day (Open width & tubular finish). Production Capacity in knitting: 10000-12000 kg. Of Greige fabric and 25000 pieces of cuff & collar set per day (depends on design i.e. if design is more than production will be less). Production Capacity in yarn dyeing: 4000 kg. Per day Production Capacity in knit dyeing: 30,000 Kg. Per day Investment Cost: Investment cost is US$ 7.50 million. Remarks: N.R.G. Knit Fabric Ltd. is greatest concerned with the quality of its product. For this reason it do not look for the production volume rather the quality of product, this increase its overhead cost. But better quality has welcome buyers with satisfaction. The infrastructure and land asset has the greatest possibility to extension and to create social contributions.
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Chapter-3 Manpower Management
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Organogram of Administration:
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Organogram of Operation:
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An overall Organogram:
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Shift Change: There are three shifts for operation personnel in this industry. So the shifts are changed at every 8 hours. The shift timings are as below: 6:00 am to 2:00 pm (“A” Shift) 2:00 pm to 10:00 pm (“B” Shift) 10:00 pm to 6:00am (“C” Shift) Administration i.e. Management personnel work on General (G) shift of duration 8:00 am to 5:00 pm and 6 days per week. Responsibilities of Production Executive: To follow and execute the daily production plan accordingly. To give the right decision for the minor troubleshooting. To match the shade with the approved lab dip and take necessary help from Spectrophotometer. To prepare dye line correctly and maintain logbook. To convey the proper information to the next shift. To maintain target productivity of every section in his shift To give job card to maintenance department whenever machine is not working or any other problem with the machine. Job description of Production Executive: Report to: Senior production officer Job Summary: To plan, execute & follow up the production activities & control the quality.
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Duties & Responsibilities: Overall supervision of dyeing, finishing production. Batch preparation & PH check. Dyes & chemical requisition issue & check. Write fabrics loading & unloading time from m/c. Program making, sample checking, color measurement. Control the supervisors, operators’ asst. operator & helpers of dyeing m/c. And also any other work as & when required by the management. Job Responsibilities of Production officer and senior Production Officer:
To keep workers attendance Distribute the workers to various machines To distribute yarn according to order No. and Lot. To prepare production register after every shift To maintain log book To report shift wise floor production to Sr. Executives/ Executives To monitor product quality To take all types of initiatives to increase production To take all types of initiatives to reduce wastage
Management System: Corporate management system. Remarks: NRG Composite Yarn Dyeing Ltd. has manpower more than 6000 in around a single fence & N.R.G Multi Fabrics Ltd. Has around 200s manpower. N.R Group pay a great attention for providing food and transport, medical, schooling of personnel’s children, their utility and maintain a safe, secured and calm environment. The working condition here is also standardized. These opportunities for the personnel of the industry have a direct positive impact on the production and also motivate the personnel for better and greater efficiency.
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Chapter-4 Raw Materials
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NRG Composite Yarn Dyeing Ltd. is a knit composite textile industry. In the industry raw materials for different section is different. As for example knitting uses the raw material Yarn, Fabric processing department uses the knit fabrics, dyes and chemicals again yarn processing uses the grey yarn and dyes chemicals. Following we describe the raw materials used in NRG Composite Yarn Dyeing Ltd.
Yarn Grey fabrics Dyes Chemicals Auxiliaries
Yarn: Following types of yarns are used to knit fabrics:
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Grey Fabrics: Following types of grey fabrics are dyed:
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Sources: The required yarns are supplied from:
N.R Group Spinning Mills Ltd. (Bangladesh) Thermax (Bangladesh) NRG (Bangladesh) Badsha Spinning Mills Ltd. (Bangladesh) Ginni (India) Nahar (India)
And special yarns are from: Bardhaman (India), Aarti (India), Organic cotton – Indonesia. The required grey fabrics are produced in this industry
Price: Not provided.
Dyes: The following dyes are usedReactive dyes. Disperse dyes. The list of dyes for different substrate is as below:
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For Cotton Group (Reactive Dyes)
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Chemicals: Basic Chemicals
Acid Buffer: Sodium Acetate Ammonium Sulphate
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Bleaching Agent
Salt/Electrolyte
Caustic Soda
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Detergent and Scouring Agent
Antifoam/ Penetrating Agent
Anti-Creasing Agent
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Peroxide Stabilizer
Peroxide Killer
Sequesterent & Dispersent for Bleaching
Mercerizing Wetting Agent
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Leveling Agent for Heat Setting
Reactive Fixing Agent
Cotton Leveling & Prof-Colloid
Oxidizing Agent for Polyester
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Dispersing Leveling Agent for Polyester
Acid PH Buffer (For Polyamide)
Setavin PAS
After Soaping Agent
Gliding Agent for Cotton Yarn
Reducing Agent
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Enzyme Finishing Agent
Optical Brightener for Cotton
PES-Dyeing PH Buffer
Rubbing Fastness Improver
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De-Colorant for Effluent Treatment
Ultra violet protection Agent
Anti-murobiol Hygiene Protection Agent
Silicon Stripper Agent
Knitting Oil Removing Agent
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Special Finishing Agent
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Softener
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Chapter-5 Literature Review
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Cotton Fiber and its Chemical Structure The chemical composition of cotton, when picked, is about 94 percent cellulose; in finished fabrics is it 99 percent cellulose. Cotton contains carbon, hydrogen, and oxygen with reactive hydroxyl groups. Glucose is the basic unit of the cellulose molecule. Cotton may have as many as 10,000 glucose monomers per molecule. The molecular chains are arranged in long spiral linear chains within the fiber. The strength of a fiber is directly related to chain length. Hydrogen bonding occurs between cellulose chains in a cotton fiber. There are three hydroxyl groups that protrude from the ring formed by one oxygen and five carbon atoms. These groups are polar meaning the electrons surrounding the atoms are not evenly distributed. The hydrogen atoms of the hydroxyl group are attracted to many of the oxygen atoms of the cellulose. This attraction is called hydrogen bonding. The bonding of hydrogen's within the ordered regions of the fibrils causes the molecules to draw closer to each other which increases the strength of the fiber. Hydrogen bonding also aids in moisture absorption. Cotton ranks among the most absorbent fibers because of Hydrogen bonding which contributes to cotton's comfort. The chemical reactivity of cellulose is related to the hydroxyl groups of the glucose unit. Moisture, dyes, and many finishes cause these groups to readily react. Chemicals like chlorine bleaches attack the oxygen atom between or within the two ring units breaking the molecular chain of the cellulose.
Chemical structure of Cotton Fiber
Bleaching Bleach is a chemical that removes colors or whitens, often via oxidation. Common chemical bleaches include household "chlorine bleach", a solution of approximately 3–6% sodium hypochlorite (NaClO), and "oxygen bleach", which contains hydrogen peroxide or a peroxide-releasing compound such as sodium per-borate, sodium per-carbonate, sodium persulfate, sodium per-phosphate, or urea peroxide together with catalysts and activators, e.g. tetraacetylethylenediamine and/or sodium nonanoyloxybenzenesulfonate. To bleach something is to apply bleach, sometimes
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as a preliminary step in the process of dyeing. The bleaching of textiles appears to have been known as early as 300 B.C. when soda ash was prepared from burned seaweed and used to clean cloth. Then the cloth was treated with soured milk to reduce its alkalinity. The bleaching process was completed when the cloth was exposed to the Sun. This type of sun bleaching typically took several weeks. A Swedish chemist discovered chlorine gas in 1784 and succeeded in demonstrating its use for decolorizing vegetable dyes. Fifteen years later a patent was awarded for a bleaching powder formed by the absorption of chlorine gas into dry hydrate of lime. Following World War I the technology for shipping liquid chlorine was developed. This allowed for on-site production of sodium hypochlorite in textile mills and led to the development of other chlorine-based bleaches. In 1928, the first dry calcium hypochlorite bleach containing 70% available chlorine was produced in the United States. This material largely replaced bleaching powder in commercial bleaching. Hydrogen peroxide was prepared as early as 1818 but did not find use in the bleaching of textiles until much later. By 1930, the prices of peroxides had dropped sufficiently to allow the use of hydrogen peroxide in the bleaching of cotton, wool, and silk. By 1940, 65% of all cotton bleaching was done with hydrogen peroxide. Textile bleaching is one of the stages in the manufacture of textiles. All raw textile materials, when they are in natural form, are known as 'greige' material. This greige material will be with its natural color, odor and impurities that are not suitable for clothing materials. Not only the natural impurities will remain on the greige material but also the add-ons that were made during its cultivation, growth and manufacture in the form of pesticides, fungicides, worm killers, sizes, lubricants, etc. The removal of these natural coloring matters and add-ons during the previous state of manufacturing is called scouring and bleaching.
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Bleaching Chemistry The process of bleaching can be summarized in the following set of chemical reactions: Cl2 (aq) + H2O (l) H (aq) + Cl (aq) + HClO (aq) +
-
The H+ ion of the hypochlorous acid then dissolves into solution, and so the final result is effectively: Cl2 (aq) + H2O (l) 2H (aq) + Cl (aq) + ClO (aq) +
-
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Hypochlorite tends to decompose into chloride and a highly reactive form of oxygen: ClO Cl + O -
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This oxygen then reacts with organic substances to produce bleaching or antiseptic effects.
Reactive Dyes The best dyes, by far, to use for cotton and other cellulose fibers are the fiber reactive dyes. They are much brighter, longer-lasting, and easier-to-use than all-purpose dyes. Reactive dyes first appeared commercially in 1956, after their invention in 1954 by Rattee and Stephens at the Imperial Chemical Industries Dyestuffs Division site in Blackley, Manchester, United Kingdom. Reactive dyes are used to dye cellulosic fibres. The dyes contain a reactive group, either a haloheterocycle or an activated double bond, that, when applied to a fibre in an alkaline dye bath, forms a chemical bond with a hydroxyl group on the cellulosic fiber. Reactive dyeing is now the most important method for the coloration of cellulosic fibres. Reactive dyes can also be applied on wool and nylon; in the latter case they are applied under weakly acidic conditions. Reactive dyes have a low utilization degree compared to other types of dyestuff, since the functional group balso bonds to water, creating hydrolysis.
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Reactive dyes are categorized by functional group:
Dyestuffs with only one functional group sometimes have a low degree of fixation. To overcome these dyestuffs containing two different reactive groups (i.e. one monochlorotriazin and one vinyl sulfone) were created. Bifunctional Dyestuffs containing two groups are also known as bifunctional dyestuffs, though some still refers to the original combination. Other type of bifunctional dyes has been introduced. The first bifunctional dye made where more tolerant to temperature deviations (better process). Other bifunctionals are created, some with fastness (better quality) or only fixation degree (better environment/economy) in mind. Reactive dyes have good fastness properties owing to the bonding that occurs during dyeing. Cotton is made of cellulose molecules which react with the dye .During reactive dyeing the H atom in the cellulose molecule combines with the cl atom in the dyeing process and results in a bond. Trifunctional dyestuffs also exist. Procion MX. Many people feel quite strongly that the best dye choice for the beginner, as well as for many experienced dyers, is Procion MX, because this dye is very easy to work with.because this dye is very easy to work with.
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The dyes are relatively non-toxic. Other advantages include the remarkable wash fastness found in all fiber-reactive dyes. Optimum reaction temperatures for Procion MX dyes are between 95° and 105°F = 35° to 41°C (except for turquoise, which prefers up to 130°F = 55°C) Cibacron F. Another very good fiber reactive dye for artists and crafters to use is the Cibacron F line. (Don't confuse Cibacron F with just plain Cibacron! They can be completely different types of dyes; be sure you get the type with the "F" suffix.) Like Procion MX dyes, Cibacron F dyes can be used in warm water, instead of extremely hot water like some dyes. Its advantages over Procion MX dyes are that it 'keeps' better in solution, so you can store and possibly even buy it already in solution (liquid form), avoiding the safety hazard of breathing dye powder; it is also much easier to wash the excess dye out of the fabric when using Cibacron F dyes than when using Procion MX. However, the Cibacron F line has one major drawback when compared to the Procion MX line: there is not as wide a choice of colors. Cibacron F dyes can be used according to the exact same recipe as Procion MX dyes, and even mixed freely with them. However, Cibacron F dyes are slightly less quick to react than Procion MX type, which is why they can be stored so much longer after dissolving them in water than the Procion MX type dyes; this also means that slightly higher temperatures are needed. Optimum temperatures for Cibacron F dyes are slightly higher than for Procion MX dyes. Ciba says 55° to 65°C (130° to 150°F); ProChem (Sabracron F) says 45 to 55°C. (113° to 130°F) Drimarene K. This is the remaining popular "cool water" fiber reactive dye. It requires higher temperatures still than Cibacron F, but does not require steaming. Instructions for Drimarene K dyes can be found at Batik Oetoro; they are very similar in action to MX type dyes, except for requiring a minimum temperature of 35°C or 95°F. The greatest drawback, besides the need to find a warm place for the dye reaction to occur, is the lack of a truly rich red. Drimarene K has optimum temperatures around 60°C (140°F) for most colors, 80°C (176°F) for turquoise and a couple of others. Procion H dyes are usually used for silk painting; they require steaming or simmering to fix to cotton or silk. They are chemically similar to Procion MX dyes, being monochlorotriazines, but they are far less reactive, and will not work at all well at room temperature.
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Procion H dyes, may be fixed to cotton using a high-pH solution such as sodium silicate at room temperature, or by moderate heating. Vinyl sulfone dyes are particularly useful for chemical resist dyeing, in which two different types of fiber reactive dyes are used to print foreground and background in different colors. Remazol dyes are more suitable for dyeing for later discharge (bleaching) than are other fiber reactive dyes. Levafix. made by Dystar, for small-scale users. Their temperature optimum is around 50°C (122°F). This is lower than the optimum temperature of 60° to 80° C. for the Drimarene K dyes, which can be used in "cold" dyeing, but higher than the optimum temperature of about 35° to 40°C (95° to 105°F) for Procion MX. It is not necessary to get quite as high as the optimal temperature in order to have acceptable results.
Dissolving the Dyes The dyes are in most cases readily water-soluble. They are dissolved either by passing with cold water to which is then added hot water or by strewing the dye powder into hot water which is stirred at high speed. Usually a temperature not greater than 80ºC is used for dissolution. In the case of highly reactive dyes such as Procion MX (ICI) warm (50-60ºC) water is used. Since the dyes are prone to hydrolysis stock solutions should not be stored for long periods. Reaction with Cellulosic fiber Reactive dyes formed covalent bond with cellulosic fiber by Nucleophilic substitution and addition reaction. The reactions are as follows ----Substitution reaction: D – R – Cl + HO - Cell D – R – O – Cell + HCl
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Addition reaction: D – F – CH2 = CH2 + HO – Cell D – F – CH2 – CH2 – O – Cell Reaction with water: The cold brand reactive dyes are highly reactive in nature. They react also with water and get hydrolyzed. The reaction is as follows ---D – R – Cl + HOH D – R – OH + HCl The hydrolyzed dye is also colored substances and has very low substantivity for the cellulosic fiber. So they are attached with fiber surface after dyeing. If they do not washed away from the fiber surface the fastness property of the fiber must be very low. Salts used for Reactive Dyeing Depends on the substantivity, salts like common salt (NaCl) or Glauber’s salt (Na2SO4) is used. Alkalis for Reactive Dyeing The common alkalis used for reactive dyeing are sodium bi-carbonate (NaHCO3), sodium carbonate (Na2CO3), sodium hydroxide (NaOH), sodium silicate (Na2SiO3) and sodium phosphate (Na3PO4). Sodium silicate is very strong alkali and only used for deep dyeing. Sodium carbonate is mostly used alkali in reactive dyeing. Eliminating the hydrolyzed dye The hydrolyzed dye is also colored substances and has very low substantivity for the cellulosic fiber. They tend to stay on the fiber surface after dyeing for sometimes although there is no bond between the dye and the fiber. These unfixed dyes come of the fibers when washed or rubbed subsequently. If they do not washed away from the fiber surface the rubbing and wash fastness property of the fiber must be very low. The presence of electrolytes in the washing water causes an increase in the hydrolyzed dye affinity making it difficult to extract, therefore very saline water must be avoided even if this water conditioned.
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Optical Brightener Optical brighteners, optical brightening agents (OBAs), fluorescent brightening agents (FBAs) or fluorescent whitening agents (FWAs) are dyes that absorb light in the ultraviolet and violet region (usually 340-370nm) of the electromagnetic spectrum, and re-emit light in the blue region (typically 420-470nm). Fluorescent activity is a short term or rapid emission response, unlike phosphorescence, which is a delayed emission. These additives are often used to enhance the appearance of color of fabric and paper, causing a perceived "whitening" effect, making materials look less yellow by increasing the overall amount of blue light reflected. Properties The most common classes of chemicals with this property are the stilbenes and older, noncommercial fluorescent dyes such as umbelliferone, which absorb energy in the UV portion of the spectrum and re-emit it in the blue portion of the visible spectrum. A white surface treated with an optical brightener can emit more visible light than that which shines on it, making it appear brighter. The blue light emitted by the brightener compensates for the diminishing blue of the treated material and changes the hue away from yellow or brown and toward white. There are approximately 400 brightener types listed in the Color Index, but less than 90 are actually produced commercially and only a handful are commercially important. Generically, the C.I. FBA number can be assigned to a specific molecule, however, some are duplicated, since manufacturers apply for the index number when they produce it. The global OBA production for paper, textiles and detergents is dominated by just a few di- and tetrasulfonated triazole-stilbenes and a di-sulfonated stilbene-biphenyl. These are subject to fading when exposed long term to UV, due to the formation of optically inactive stilbene cisisomers found at the center of the molecule. All brighteners have extended conjungation and/or aromaticity, allowing for electron movement. Some non-stilbene brighteners are used in more permanent applications such as whitening synthetic fiber. Basic class types of brighteners include:
Triazine-stilbenes (di-, tetra- or hexa-sulfonated) Coumarins Imidazolines Diazoles Triazoles Benzoxazolines Biphenyl-stilbenes
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Brighteners can be "boosted" by the addition of certain polyols like high molecular weight polyethylene glycol or polyvinyl alcohol. These additives increase the visible blue light emissions significantly. Brighteners can also be "quenched". Too much use of brightener will often cause a greening effect as emissions start to show above the blue region in the visible spectrum. Besides the formation of cis isomer in stilbene-containing brighteners (only the trans isomer is optically active), continued exposure to UV-containing light will actually cleave the molecule and start the process of degradation. Common uses Brighteners are commonly added to laundry detergents to replace whitening agents removed during washing and to make the clothes appear cleaner. Optical brighteners have replaced bluing which was formerly used to produce the same effect. Some brighteners can cause allergic reactions when in contact with skin, depending on the individual. Brighteners are used in many papers, especially high brightness papers, resulting in their strongly fluorescent appearance under UV illumination. Paper brightness is typically measured at 457nm, well within the fluorescent activity range of brighteners. Paper used for banknotes does not contain optical brighteners, so a common method for detecting counterfeit notes is to check for fluorescence. A side effect of optical whitening is to make the treated fabrics more visible with Night Vision Devices than non-treated ones. This may or may not be desirable for military or other applications. Optically brightened paper is often not useful in exacting photographic or art applications, since the whiteness decreases with time. Endues of optical brighteners include:
Detergent whitener (instead of blueing agents) Paper brightening (internal or in a coating) Fiber whitening (internal, added to polymer melts) Textile whitening (external, added to fabric finishes)
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Mercerization Mercerized cotton is cotton which has been treated with sodium hydroxide to bring out certain properties first discovered by John Mercer in 1851. In 1890, Horace Lowe added an additional step to the process, and the British cotton industry began to take an interest in mercerized cotton, which is available today in a wide range of incarnations from thread to completed garments. When treated properly, mercerized cotton is stronger, smoother, and shinier than regular cotton. In addition, it takes dye more readily so that manufacturers can create rich color saturation in their cottons. The brilliant, lustrous hues of Mercerized cotton can be found in fabric stores, yarn shops, and department stores all over the world. John Mercer discovered that immersing fibers such as cotton and linen in a caustic soda bath would increase their strength and also allow them to take dye more readily. He patented his fiber work, but the cotton industry did not express very much interest in it. It was Horace Lowe who popularized the process, by discovering that keeping the fibers under tension while they were soaked yielded a more lustrous thread. Mercer's name is presumably given to the process to recognize his important initial discovery, which paved the way to Lowe's refinement of the treatment. Mercerization starts with gathering the cotton and spinning it normally. Because cottons with long fibers take better to mercerization, Pima, Egyptian, and Sea Island cotton are usually chosen for the process. The cotton thread is held under tension and submerged in a highly alkaline bath of sodium hydroxide in a percentage which ranges, but usually hovers around 22%. After treatment, the mercerized cotton is placed into an acidic bath to neutralize it. Once this process is complete, the cotton can be dyed and knitted, woven, or packed as standalone spools of thread. The terms "pearl cotton" and "pearle cotton" are also used to refer to Mercerized cotton, because of the deeply lustrous appearance of the finished cotton thread. In addition to having rich color saturation and a shimmering appearance, mercerized cotton is also much stronger than conventional cotton thread. The process shrinks the cotton fibers, tightening and smoothing the grain of the thread. Because the cotton is preshrunk, mercerized cotton also tends not to shrink as much as regular cotton, so consumers can be more confident about the fit of mercerized garments.
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Mercerization Process Single Mercerization is a process in which the yarn used to make a shirt is run through the middle of an open flame at a very high speed. It passes through so quickly that the yarn itself doesn't burn but the millions of fuzzies and slubs on the yarn are eliminated instantly. This makes the yarn stronger. Since there is no fuzz on the yarn, it is held together better and can no longer unravel by it-self. The yarn is also less prone to shrinking because the mercerization process literally pre-shrinks the fabric. Mercerization also cleans the yarn and gives it a strong affinity for dye. While normal cotton yarn has no clarity or depth to it's color, Mercerized yarn accepts the dye much better and the colors come out deeper, sharper and have a very clean look. The fabric now looks and feels ten times better. Single Mercerization is a huge step up from the quality of regular cotton shirts but Double Mercerization takes it even a step further. During the knitting process some fuzzies will ultimately resurface. In Double Mercerization the knitted fabric undergoes a second Mercerization process to remove these. The fabric is placed in a chemical bath using caustic soda to once again remove any additional fuzzies or slubs and is then washed clean. This makes the fabric even stronger and makes it look and feel even better. It has a luster and sheen that is unmatched. Double mercerized fabric feels so soft and smooth its look and feel can easily be mistaken for silk.
57
Chapter-6 Chemical Laboratory
58
Chemical Lab Lay-Out
59
Description of the Chemical Lab Layout
60
Introductory instruments of Chemical Lab:
These following equipment are used in chemical lab: Conical Flux Glass Beaker Glass Cylinder Pipette Werrtlab Glass Rod Dyes Pot Dyes or Caustic measurement steel spoon Hand Gloves Mask and Googles Pipette Filter Burrette PH Meter Balance Plastic Beaker Scotch Tape, Maskin Tape, Both side tape Scotch Tape Holder Volumetric Flask PH Paper Peroxide Paper Thermometer Caustic Boume Meter Firsape Beaker wash brush EDP Scussor Burrette stand
61
Chemical Lab Organogram:
Senior Manager Deputy Manager Executive -i Executive-ii Senior Lab assistant Lab assistant Junior lab assistant
62
Working Procedure for Chemical Laboratory:
Requisition receive from buyer/ merchandiser Standard receive from buyer/merchandiser Recipe open by visually/data color Combination select by lab/floor responsible person Fabric record list by PO/APO Fabric requisition to knitting according to buyer requirement Coming fabric from knitting and dyeing floor checking
Checking issues:
Buyer Style Number NRG Number Yarn Lot Yarn count Fabric composition Fabric type Fabric absorbency
63
Fabric whiteness Bio kill/Remove H2O2
Lab Machineries: 1. Machine Name: Auto Dispenser Company Name: TLOS Country Name: Greece Function: At a time 24 solutions are done Capacity: Accuracy .0001 Description: - Auto dispensing system is used. - Robolab software is used. - Powder Beaker - EDP is not possible 2 unit maximum but possible at Robolab - Glass beaker number is 84.
2. Machine Name: Ahiba IR (Pro)
Company Name: Data Color Country Name: USA 64
Fiber Type: All Minimum Liquor Ratio: For natural 1:5, For Synthetic 1:4 Temperature Ratio: 20-1400 Celcius Infrared Lamp: 3 KW Speed: 5-50 (Selectable) Program Storage: Up to 99 programs Languages: 7 Languages
3. Machine Name: Top Speed II
Company Name: Ahiba Nuance Country: USA Function: Dyeing is done with program setting.
65
4. Instrument Name: Sink
Nomenclature: Washing Chamber Function: - Here, some soaping chemicals are used. For example: ADW and Ladiquest can be mentioned. - Hot and cold wash is done.
5. Machine Name: Washing Machine Nomenclature: Rapid washing machine Country: USA Conical Flux Number: 24
Functions: - Hot wash is done at 950 Celcius - 1st wash is done at 15 minutes - 2nd wash is done at 15 minutes, i.e, 30 minutes is required
66
6. Machine Name: Quick Wash Company Name: SDL ATLAS Country: China
Functions: - Yarn and fabric is washed by spin - Water is out from fabric or yarn - Required time 20 seconds
7. Machine Name: Microprocessor PH meter Company Name: Hanna
67
Country: USA Nomenclature: Memorizing Reading Functions: - Memorizing reading - Memory recall - Select PH
8. Machine Name: Spectrophoto Meter
Brand Name: Data Color Country: USA Rating: 100-240V, 47-263 Hz, 100V A Functions: - Software recipe formulation -R value input -Color fastness assessment
68
9. Machine Name: Light Box Model: CAC 120-5 Serial Number: E883806 Type of tests: All color fastness Used Methods: C01, C08, E01, E04, X12 or EOS Lights Used: CWF, D65, TL 84, UV
10. Machine Name: EDP (Electronic Digital Pipette) Country: USA
Function: This device complies with 15-j fec rules. Capacity: 10 ml 11. Machine Name: Electronic Digital Balance Company Name: OHAOS Crop, Usl Country: USA
69
Maximum Capacity: 110 grams Functions: Measurement of salt, soda and different types of fabric samples.
Working Procedure of dyeing in chemical Lab: The following flowchart is strictly maintained throughout the chemical lab procedures. And is compulsory to maintain it if we are to ensure maximum quality product with highest efficiency. The flowchart is given below---
70
Stock solution preparation Pipetting preparation Bleached fabric loading Salt dosing Machine loading and running Soda, Alkali dosing and running Unload Dryer Keeping record
71
Process Flowchart Description:
Data Color and PH Meter Calibration System: Data color should be calibrated 3 times a day between 5.0 AM to 6.0 AM, 1.0 PM to 2.0 PM and 9.0 PM to 10.0 PM. PH meter should be calibrated 3 times a day. PH buffer should be replaced once per week.
Fabric preparation for Lab dip and Bulk Checking: Find the correct fabric for dyeing. Take accurate measurement as possible and try not to hurry. The fabric weight should be written on the right corner of the top of worksheet. Do the quick wash process completely and load the fabric immediately after quick wash. After Quick wash amount of water inside fabric vary each and every minute. For bulk checking, order number, yarn lot, GSM could be 100% maintained as per worksheet information.
Stock Solution Preparation:
Prepare the stock solution daily morning. Use cold water to dissolve dyes. Take accurate measurement of solid powder dyes keeping all air condition off. Prepare stock solution of 0.001%, 0.1%, 0.5%, 1.0%, 2.0%, and 4.0% only for dark and navy shades.
Worksheet Preparation: While preparing worksheet, we have to write properly fabric construction, Buyer name, Color code, Recipe number, Liquor ratio, Program number, Fabric code and Style number very carefully.
72
Salt Measurement System: Take accurate measurement of Glauber or Refined salt. Make sure that Glauber or Refined salt is used. Measure the entire salt amount within 15 minutes.
Loading System:
Sensor water change. Correct program and follow the monitor graph. Follow the machine temperature. Don’t open the door after temperature exceeding 800 Celcius. If the rubber cap gets broken then it must be changed. Follow the program. Follow the full time during dyeing. Soda dosing in due time. Don’t left pipettes pot open for more than half an hour. Load the batch within half an hour after pipetting.
Wash Off: For washing off samples after dyeing following flowchart is followed on Chemical Lab:
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Unload
Cold wash
Neutralization with Sirrix NE (0.50 g/l) PH =6.0-6.50 adjusted at 500 Celcius temperature
Soaping (Eriopon OS)
Hot Wash (Rapid Machine)
Drying
Dry the sample:
After washing, the samples are kept in quick wash machine for 0.5-1.0 minutes. Also carefully maintain the fact that counting the sample correctly to put in and out for avoiding the outline problem. Fabrics samples are lye on, on the dryer and yarn keep spreading. Cotton fabrics sample should be dry on Tumble dryer and polyester, yarn dry on the line dryer as per setting temperature, After drying, the sample is kept out and relaxed then attached to the worksheet for evaluation.
74
Data Color Report: Measure the standard swatch and save. Measure the sample with actual standard or swatch. Different types of data value write on the worksheet properly according to the sample number.
Visual Assessment: Buyer wise light source selection before shade checking. Malting the shade with actual standard and data value reports. If the shade is 95%+ matching visually and data value report could be selected.
Final Shade Selection: For final shade selection, lab employees have to follow buyer selected light source, requirement tolerance, direction etc.
Shade Submission for Approval: Selected samples are submitted according to the buyer requirements, date, style, order number. The submitted samples and writing out looking must be fine without overwriting.
Table Work: Here in NRG Composite Yarn Dyeing Ltd. chemical lab, some processes are maintained carefully. Such as
Buyer list Production card making (Yarn) Production card making (Fabric) Lab Dip submission.
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Lab dyeing Program and Procedure: For Cellulosic Material
Sample+Color+Salt+Levelling agent (Albatex 1 g/l)
600 x 20 min
Machine halt for dosing
Dosing soda ash and caustic soda
600 x 20 min
Machine stop
Rinse
Neutralization with Acetic Acid
Soaping using rapid soaping machine
Washing
Drying
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Program for Polyester:
Sample + Color + Underdin DIF (1 g/l) + Albatex AB 45 (1 g/l)
30x45
Lowering temperature at 600 Celcius
Machine Stop
Reduction clearing by Rapid soaping machine [Hydrose (1 g/l)+NaOH (1 g/l)]
Neutralization
Washing
Drying
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Program: Turquoise Color
Sample+Colo+Salt+Leveling [Albatex DBC (1 g/l)]
80 x 20
Cooling at 700 Celcius [
40C/min]
Machine halt for dosing
Dosing soda ash and caustic soda
800 x 40
Machine Stop
Rinse
Neutralization with Acetic Acid
Soaping using Rapid soaping machine
Washing
Drying
78
Dyes Name
Supplier Name
Novacron Navy FN-BN
Huntsman
Novacron Dark Blue W-R
Huntsman
Novacron Red FN-2BL
Huntsman
Novacron Ruby S-3B
Huntsman
Novacron Yellow NP
Huntsman
Novacron Blue FNR
Huntsman
Novacron Blue TS 3G
Huntsman
Novacron TS-GC
Huntsman
Novacron Ocean SR
Huntsman
Novacron Deep Orange S-4R
Huntsman
Novacron Deep Cherry S-D
Huntsman
Novacron Deep Night SR
Huntsman
Novacron SScarlet FN-6G/C-6G
Huntsman
Novacron Brill Red FN-3G
Huntsman
Cibacron Super Black G/Novacron
Huntsman
Cibacron Super Black R/Novacron
Huntsman
Corafix Violet GDB
Hi-Tech color-chemicals
Moderzol Black F-C-N
TMA Corporation
Moderzol Turquoise Blue G-133%
TMA Corporation
Moderzol Turquoise Blue G-266%
TMA Corporation
Drimaren Navy CL-R
Clariant Export AG
Drimaren Navy K3R
Clariant Export AG
Kimsoline Red KLL
Kimsoy
Kimsoline Yellow KLL
Kimsoy
Kimsoline Blue KLL
Kimsoy
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Kimsoline Br. Blue DBR
Kimsoy
Kimsoline Red KED
Kimsoy
Vivizol Red DBR
Kimsoy
Blue Shade BL
Kimsoy
Yellow Shade SL
Kimsoy
Red Shade 3B
Kimsoy
Parafix Turquoise Blue G266%
Celustar Dye-Chemicals
Liyuansol Turq Blue-266%
Celustar Dye-Chemicals
Liyuansol Blue RSPL 150%
Celustar Dye-Chemicals
Levafix Blue CA Gran
Dystar
Levafix Brill Red E-4BA
Dystar
Levafix Brill Red E-BA
Dystar
Levafix Brill Red F-6BA
Dystar
Levafix Amber CA/CA-N
Dystar
Levafix Brill Blue E-FFN
Dystar
Levafix Fast Red CA
Dystar
Levafix Orange CA
Dystar
Levafix Brill Yellow CA
Dystar
Remazol Luminous Yellow FL
Dystar
Remazol Dark Blue SLT
Dystar
Remazol Red RR
Dystar
Remazol Blue RR
Dystar
Remazol Brill Blue BB New GM 133
Dystar
Remazol Brilliant Yellow 3GL
Dystar
Remazol Yellow RR
Dystar
Remazol Deep Red RGB
Dystar
Remazol Red RGB Gran
Dystar
Remazol Golden Yellow RGB Gran
Dystar
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Remazol Brill Red F-3B
Dystar
Remazol Ultra Carmine RGB
Dystar
Remazol Ultra Yellow RGB
Dystar
Remazol Navy Blue RGB
Dystar
Remazol Green 6B-T
Dystar
Remazol Turquoise GN 266%
Dystar
Remazol Turquoise Blue G133%
Dystar
Setazol Blue R Special
Satas Kimya
Setazol Brilliant Red SB
Satas Kimya
Sunzol Ultra Yellow RGBN/GRBN
Huntsman
Solophenyl Yellow ARLE-154%
Huntsman
Solophenyl Red 7BE
Huntsman
Solophenyl Blue FGLE
Huntsman
Everzol Yellow 3GL
Everlight
Everzol Turquoise Blue G
Everlight
Everzol Navy Blue GG
Everlight
Everzol Blue ED-G
Everlight
Everzol Brill Blue RSPL
Everlight
Everzol Black GR
Everlight
Eibazol Black HG/ Superb Black
Well Prospering
Avitera Yellow SE
Huntsman
Avitera Deep Sea SE
Taha Colors
Avitera Light Red SE
Taha Colors
Avitera Light Blue SE
Taha Colors
Avitera Blue SE
Taha Colors
Avitera Orange SE
Taha Colors
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Avitera Red SE
Taha Colors
Avitera Deep Blue SE
Taha Colors
Jinjipai Red SNE
Taixing Jinyun Dye
Jinjipai Turquoise HFG (266%)
Taixing Jinyun Dye
Argazol Brilliant Blue RSPL/ R Conc
Argus
Bezaktiv Navy SBL
Bezema
Bezaktiv Blue V RSPL
Bezema
Bezaktiv Red S-2B
Bezema
Bezaktiv S-3B
Bezema
Bezaktiv Yellow S-3R
Bezema
Bezaktiv Violet V-5R
Bezema
Capacity of the Lab: Total Sample Dyeing machine: 07 Total Pot/ Beaker: 95 pieces Per day sample delivery: 30 shades Per month Sample delivery: 900 shades
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Buyers of N.R GROUP Fashios Ltd. are named below:
Tema Beratta S. Olivier Leross M and S E. Straws Esprit Malfini Puma MPL Mexx Casamoda C. House Creasion Mothercare Police Ashcity Grey Stone H&M
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Chapter-7 Production Planning Sequence Operations Knitting: Knitting is a method by which yarn is manipulated to create a textile or fabric .Knitting creates multiple loops of yarn, called stitches, in a line or tube. Knitting has multiple active stitches on the needle at one time. Knitted fabric consists of a number of consecutive rows of interlocking loops. As each row progresses, a newly created loop is pulled through one or more loops from the prior row, placed on the gaining needle, and the loops from the prior row are then pulled off the other needle. Types of Knitting: Warp Knitting Weft Knitting Knitting Floor Lay- Out:
84
Specification of Knitting Machine:
Different circular knitting m/c:
PAILUNG S/J CERCULAR KNITTING M/C Knitting M/C
85
MAYER & CIE S/J Circular
Important components of Knitting M/C:
\ Standing Creel Feeder
Needle Cam
86
Positive
Yarn Guide
Cylinder 87
VDQ Pulley
Fabric Spreader
Function of different parts of the machine:
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Yarn Package Career: Yarn package career contains the yarn. Needle: An element which forms loops and wales. Tricks: Slots which guide needles during knitting. Cylinder: A cylinder drum which contains slots, needles and sinkers. Dial: A horizontal plate which contains slots and horizontal needles. Yarn Guide: Its guide the yarns from package to Dial/Cylinder Dial Cams: It helps in the movement of dial needle. Cylinder Cams: Its helps in the movement of cylinder needle. Oiling: Oiling needs in knitting m/c because of abrasion free movement of needles cams. Sensors: Sensors used in knitting m/c find out the yarns breakage during knitting process. Motor: Motor is the top most important parts of knitting m/c. Motor is used to transfer the motion to cylinder and Dial. Roller: Rollers are used to take up the fabric. Belts: Belts are used to connect the pulley to each other.
Yarn Path diagram:
89
Raw Materials: Cotton yarn Carded yarn Combed yarn Organic cotton
Viscose Yarn Modal yarn Mélange yarn Ecru Mélange Synthetic Polyester Nylon 90
Acrylic Elastomeric Blend PC Mélange CVC
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PRODUCTION PLANNING, SEQUENCE AND OPERATIONS:
PRODUCTION PARAMETERS: a. pH: During H2O2 bleaching pH 9.2 – 12 During reactive dyeing pH 10.5 – 12.5 During disperse dyeing pH 4.5 – 6.0
b. Temperature:
For cotton scouring 900-950C For cotton cold wash 300 – 400C For cotton hot wash 700-800C For cotton acid wash 600-700C For cotton dyeing
800-900C (For hot brand)
600C (For cold brand) Polyester dyeing: 1000-1300C
c. Time:
For scouring 60-90 mins For reactive dyeing 60-90 mins For disperse dyeing 60-90 mins
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d. M:L ratio:
For reactive dyeing M:L ration maintained beween 1 : 7.5 to 1 : 10
DESCRIPTION OF PRODUCTION PROCESS:
Washing for colored fabrics:
The colored fabrics to be washed is loaded in the machine Required amount of water is taken PCLF (detergents) added & washing continued at 800C for 20 mins Cold washing
Scouring-bleaching: Fabric to be scoured is loaded in the machine Required amount of water is loaded Washing agent/ detergent is added Steam pipes are on & scouring agents (i.e. Caustic soda/ Soda ash) added when the temperature reaches at 500C When the temperature reaches at 600C then stabilizer is added Then H2O2 is added
93
Temperature is then raised to 900C and the process is then carried out for 60-90 mins depending on the requirements The liquors are then drained Then cold wash at 300-400C, hot wash at 700-800C and acid wash at 600-700C is done
Dyeing: After acid wash all liquors are drained out Required amount of water is taken Then leveling agents, anti-creasing agents, de-foaming agents are added according to the requirement Steam pipes are on & after 10-15 mins dyes are added Salts are added after another 30 mins Then soda ash after another 30 mins Then the temperature is raised slowly up to the mark The process is carried on and samples are taken after every 30-40 mins to match with the target shade. It continues until shade matching. If the sample is matched, then the liquors drained out Then cold wash at 300-400C, hot wash at 700-800C, acid wash at 600-700C is done Then softener is added at 400C for 20-30 mins Fixer is applied for deep shade only before adding softener
94
Re-dyeing: When shade is not matched then fabric is treated again in dyeing machine for shade matching is known as re-dyeing. Generally, re-dyeing is done if the shade is deeper than the target shade. It may occur when the fabrics absorb one or two colors more or less. One re-dyeing process is described below.
Drain the let off solution Hot wash at 700-800C Acid wash at 600-700C(600 for light shade & 700 for deep shade). Soda ash washes at 900-1000C for 60mins to reduce the depth of shade. Acid wash at 600C. Addition to required dyestuffs. Salt addition. Soda ash addition. Other operations are same as previous described dyeing operations.
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PRODUCTION FLOW CHART: Production flow chart for 100% cotton ↓ Grey fabric loading ↓ Scouring & Bleaching at 95oC for 1 hour ↓ Scou g HO + (95oC x 15’) ↓ H2O2 killer [invotex PC or gazyme PC] ↓ A.Acid ↓ Enzyme [pH 4 – 4.5, temp 60oC for 40’-60’] ↓ Hot wash ↓ Levelling [Ladiquest 1097] ↓ Dyeing Salt Color Soda ↓
A. Acid ↓ Hot wash [Decol SN, RSK, RFL] ↓ Fixing [VNF, ECO]
↓ Softener [LCF, Non ionic] ↓ Unload 96
Scouring
Scouring H2O2
& bleaching
hot
killer A. acid
950C 1 hr
15 m
leveling
salt
dye
700C 600C
enzyme Hot wash agent
45 – 60 min
4 0 min matl
cold wash 400C
Dyeing curve of 100% cotton fabric with reactive dye
CVC DYEING SEQUENCE:
97
soda
98
DYEING SEQUENCE FOR WHITE: Scouring + bleaching, 950 ↓ Blutton´ 50' ↓ 15' Sample test ↓ Water drain ↓ Hot (without chem.: at 800C for 20') ↓ A.cAcid ↓ ↓↓ If OKIf not oK ↓↓ SequesterSoftener ↓↓ Softener Unload ↓ Unload
dye
Detergent + 800C 20’
material
1300C 50’
½ scourig
950C Leveling & Cold wash buffering agent A. Acid
salt R. dye
Soda
600C 50’
600C
400C
Cold wash &
DYEING CURVE OF PC / CVC FABRIC WITH REACTIVE / DISPERSE DYES
99
Procedure for white colour:
Fill water and fabric loading Addition of auxiliaries (Leveling agent, Sequestering agent, Anti-creasing agent, Antifoaming agent)and runtime 10 min Raise the temp at 60 degree Alkali dosing (70% progressive dosing)and runtime 10 min Addition of Hydrogen peroxide and no runtime Dosing of optical brightening agent at 70 degree and runtime 20 min Raise the temp at 98 degree and runtime 60 min Cooling at 80 degree Drain out and fill water Addition of soaping agent 100
Raise the temp at 98 degree and runtime 10 min Cooling at 80 degree and drain out Fill water again Neutralisation with Acetic acid at 40 degree and runtime 10 min Rinse 5 min and Drain out Fill water again Softening with softener with normal water and runtime 30 min Rinse 5 min and drain out Unload fabric
Blend dyeing:
Polyester part dyeing procedure: 101
Fill water and Load fabric in machine Addition of Buffer solution Addition of dispersing agent Dosing of Disperse Dye (Linear dosing) Raise the temp at 130 degree Runtime 40 min for light shade/60 min for dark shade Cooling at 80 degree Hydrose +Caustic at 80 degree and runtime 20 min Neutralization with Acetic acid at 50 degree and runtime 10 min Rinse 5 min and fill water Raise the temp at 70 degree
102
Addition of soaping agent and raise the temp at 98 degree and runtime 10 min Cooling at 80 degree Rinse temp 5 min and Fill water again Raise the temp at 45 degree Addition of fixing agent and runtime 10 min Rinse 5 min and fill water again Softening with softener with normal water and runtime 30 min Rinse 5 min and drain out Unload fabric
103
Cotton part dyeing procedure:
Fill water in machine Fabric load in machine Raise the temp of 60 degree Auxiliaries addition (Leveling agent, Sequestering agent, Anti*creasing agent, Anti-foaming agent) Raise the temp at 70 degree Alkali dosing( 70% progressive dosing)in 10 min Addition of hydrogen peroxide at 70 degree, no run time Raise the temp at 98 degree , runtime 60 min Cooling at 60 degree 104
Drain out Filing water in the machine again Addition of soaping agent Raise the temp at 98 degree, runtime 10 min Cooling at 80 degree Drain out Fill water again Neutralization with Acetic acid Rinse temp at 50 degree and run time 10 min Check pH (should be 5.5) Drain out Fill water in machine again 105
Addition of auxiliaries (Leveling agent, Sequestering agent, Anti-creasing agent, Antifoaming agent) and runtime 10 min Salt dosing for 10 min (salt circulation) and runtime 20 min Dye dosing for 30 min (linear dosing) and runtime 30 min Alkali dosing for 40 min at 70% progressive dosing Raise the temp at 65 degree with temp gradient 1.5degree/ min and runtime 60 min Bath drain Rinse 1 or 2 times depend upon dye shade and runtime 10 min Neutralisation with Acetic acid at 50 degree and runtime 10 min Rinse 5 min and fill water Raise the temp at 70 degree
106
Addition of soaping agent and raise the temp at 98 degree and runtime 10 min Cooling at 80 degree Rinse temp 5 min and Fill water again Raise the temp at 45 degree Addition of fixing agent and runtime 10 min Rinse 5 min and fill water again Softening with softener with normal water and runtime 30 min Rinse 5 min and drain out Unload fabric
Dyeing faults: Dyeing faults are given as below:
Patchy effect : Reasons: 107
1.
Entanglement of fabric.
2.
Faulty injection of alkali.
3.
Faulty color addition.
4.
Due to hardness of water.
5.
Due to impure salt addition.
Remedies: By partial or full stripping of dyed fabric.
Roll to Roll variation / Meter to Meter variation : Reasons: 1.
Yarn lot mix
2.
Faulty heat setting
3.
Hardness of water.
4.
Faulty m/c speed.
Dye-stain : Reasons: 1.
Un-dissolved dye particle in bath.
2.
Un-dissolved caustic particle in bath.
Remedies: By partial or full stripping 108
Crease mark : Reasons: 1.
If pump pressure & reel speed is not equal.
2.
Due to high speed m/c running.
4.Rub mark: Reason : 1.
Due to reel cranking .
2.
Due to sharp point of nozzle.
3.
Due to sharp delivery roller.
5.Nozzle to Nozzle variation : Reason : Pump pressure & reel speed is not equal.
109
STANDARD RECIPE OF SCOURING & BLEACHING OF UKDL
SCOURING & BLEACHING:
DEEP SHADE 01. ALBATEX FFC
: 0.15 G/L
02. LADIQUEST 1097
LIGHT SHADE
: 0.15 G/L
: 0.25 G/L
: 0.25 G/L
03. CIBAFUUIDE C : 0.50 G/L
: 0.50 G/L
04. HOSTAPOL JU
: 2.00 G/L
: 2.00 G/L
05. CAUSTIC SODA : 2.50 G/L
: 2.00 G/L
06. SODA ASH
: 2.50 G/L
: 2.00 G/L
07. STABILIZER SF. : 0.35 G/L
: 0.30 G/L
08. H2O2 (50%)
: 3.50 G/L
: 3.00 G/L
09. ACETIC ACID
: 1.00 G/L
: 1.00 G/L
10. INVATEX PC
: 0.30 G/L
: 0.25 G/L
: 0.50 G/L
: 0.50 G/L
LEVELLING:
01. CIVAFLUDIE c
02. LADIQUEST 1097
(FOR LYCRA S/J
: 0.80 G/L
CIBAFLUIDE C
: 0.60 G/L
: 0.70 G/L)
LEVELLING: FOR TURQUISE BLUE, R-BLACK, ROYEL COLOUR
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01. CIBAFLUIDE C
: 0.70 G/L
02. LADIQUEST 1097 03. E2R
: 1.00 G/L
: 0.50 G/L
[ FOR WHITE SHADE ] H2O2 ( 50% )
: ( 4.00 G/L - 7.00 G/L)
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White Dyeing Recipe For (100% Cotton) Buyer Name :
Farnoorr M : L
Order No
:
Cross line
Batch No
:
19100
=
1:8
Mtl wt.
=
Water
=
100 kg
800 Liter
Fabric Type :
(1 * 1) Rib
G. S. M.
200 – 210 Colour
=
Serial No
Name
Dosing (g/l)
Quantity
01
Hostapol JU
0.20
160 gm
02
Cibafluide-C
0.20
160 gm
03
Albatex – FFC
0.20
160 gm
04
Cibafluide – C
0.73
584 gm
05
Hostapol JU
1.20
960 gm
06
Sequester – K
1.00
800 gm
07
Caustec Soada
2.25
1.80 Kg
08
Soda Ash
1.00
800 gm
09
Stabilizer SF
.30
240 gm
10
H2O2
4.00
3.20 Kg
11
BLUETONE – BVB
0.21 %
210 gm
12
Acetic Acid
0.60
480 gm
13
Sequester – K
0.40
320 gm
14
Softener (Non Ionic)
1.50
1.20 Kg
:
Fab dia. =
42 inch
White
112
Remarks
950 C , 60 min
Prepared by : …………………
Checked by : …………………………..
Dyeing Incharge : …………….
Production Manager : …………………..
113
Colour Dyeing Recipe (100% Cotton) With Reactive Dye Buyer Name :
D. S. L
Order No
:
Cross line
Batch No
:
19100
Water
Fabric Type :
S/J
Fab dia. =
G. S. M.
160 – 170 Colour
:
M:L
=
1:8
Mtl wt.
=
=
100 kg
800 Liter 42 inch
=
Navy
Serial No
Name
Dosing (g/l)
Quantity
01
Hostapol JU
2.00
1.60 kg
02
Ladiquest 1097
0.40
320 gm
03
Albatex – FFC
0.15
120 gm
04
Cibafluide – C
0.50
400 gm
05
Stabilizer SF
0.50
400 gm
06
Soda Ash
2.50
3.60 kg
07
Caustec Soada
3.00
2.40 Kg
08
H2O2
4.00
3.20 Kg
09
Acetic Acid
1.00
800 gm
10
Invatex PC
0.15
120 gm
11
Cibafluider – C
0.50
400 gm
12
Ladiquest 1097
0.80
640 gm
13
Reactive S Yellow F3R
0.33 %
330 gm
14
Reactive S Red F3B
0.79 %
790 gm
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Remarks
15
Reactive Black – 5
4.20 %
4.20 kg
16
Salt
62.00
49.60 kg
17
Soda Ash
20.00
16 kg
18
RFL
0.80
640 gm
19
A. Acid
1.00
800 gm
20
Softner (Non Ionic)
1.00
800 gm
Scouring
Scouring H2O2
& bleaching
hot
killer A. acid
950C 1 hr
15 m
leveling
salt
dye
700C 600C
enzyme Hot wash agent
45 – 60 min
4 0 min matl
cold wash 400C
Dyeing curve of 100% cotton fabric with reactive dye
115
soda
REMARKS: NRG strictly follow the production parameters like the time, temperature, M:L ratio pH etc. As they do some difficult shade, it takes more time for the production of the batch. Because of the trolley shortage and generator failure, the production process is sometime hampered. Considering these limitations, the production officer and the Sr. Production Officer try their best to reduce the production time.
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Chapter-8 Quality Assurance Department (QAD)
117
NRG Composite Yarn Dyeing Ltd. is more concern about quality. In this factory quality assurance is more preferred than quality control, but both are in advancement. The Quality Assurance Department is assigned to maintain consistently uniform quality of the material in process and various stages of its manufacturing. Objective of Quality Control: Research Selection of raw materials Process control Process development Product testing Specification test Scope of Quality Control, Quality Assurance and Testing: Testing Lab Machine auditing system A good training system Excellent analytical backup Technical expertise Quality Control Procedure: On line quality control Off line quality control
Off-Line Tests:
118
Quality Control Flow Chart:
119
List of Equipments: Machineries & equipment used:
Spectrophotometer with Software (Data Color) Martindale Abrasion Tester Day Light Box Sample Dyeing Machine (5) ROBO Lab Iron Electric Balance Crock Meter Washing Machine (Electrolux Wascator/Siemens) GSM Cutter PH Meter ICI Pilling Box Martindale Pilling Machine Bursting Strength Tester SDL ATLAS Rotawash Perspirometer Xenon Test Chamber Mechanical Shaker Machine
Fabric Inspection: The inspection of fabric is a procedure by which the defects of fabric are identified and fabric is classified according to degree or intensity of defects. The fabric inspection is done for both grey and finished fabric. Grey Fabric Inspection: In NRG Composite Yarn Dyeing Ltd. grey fabric inspection is performed according to 4 point system. Four-Point System: Size of Defect
Penalty
0 inches to 3 inches
1 point
3 inches to 6 inches
2 point
6 inches to 9 inches
3 point
More than 9 inches
4 point
120
Acceptance Calculation:
Any Hole – 4 Point Up to 20P/100m = Class “A” Upto 20-30P/100m = Class “B” Upto 30-40P/100m = Class “C” More than 40P/100m = Reject.
Faults found during Grey Fabric Inspection:
Wrong Design: Causes:
Wrong insertion of yarn during knitting. Wrong setting of fabric design in knitting machine. Lycra out: Causes: Lycra tears out during running the machine for production. Barrie Mark/Patta: Causes: Yarn package is either hard or soft. Lot mixing of yarn. Improper yarn tension. Uneven yarn dyeing. 121
Thick & Thin: Causes: Diameter of yarn is uneven i.e. yarn irregularity. Variation of yarn tension in course wise direction. Sinker Mark: Causes: Defective sinker. Dust in sinker. Improper servicing time of knitting machine. Needle Line: Causes: Needle mixing. Dust in needle group. Improper servicing time of knitting machine. Oil Stain: Causes: D ust in cylinder & Dial group. D ust in needle group. I mproper oil flow.
Pin Hole: Causes: Breakage of needle tail. If needle tail bends.
Loop: Causes: Dust in yarn during running the machine for production. Yarn knot thicker. Breakage of needle.
Fly Yarn: Causes: Fly fiber during knitting. One colors dirt is knitted with another color during running the machine.
Slub: Causes: Excessive ply during yarn production. Improper machine setting (Blow Room, Carding, Ring Frame). 122
Finished Fabric Inspection: 4 point numbering system is followed for finished fabric inspection. Four-Point System:
Acceptance Calculation (Classification):
< 40 PTS = A 41 – 60 PTS = B 61 – 80 PTS = C 80 ABOVE = REJECT
Faults found during Finished Fabric Inspection: Chemical Stain: Causes: Padder contains dust during silicon finish. Improper mixing of silicon softener. Improper PH of softener mixing. Too much m/c stoppage within short time.
Dirt Stain: Causes: Fabric is stored in floor. Trolley is not properly cleaned. Finishing m/c is not properly cleaned.
Oil Stain: Causes: Dust in cylinder & Dial group. Dust in needle group. 123
Improper oil flow.
124
Dye Stain: Causes: Appearance of the darker spots of the same color caused by incomplete dissolution of the dye. Improper dyes quality & dyes dosing.
Insect Spot: Causes: Fabric is finished with insect when insect is in surface area of the fabric. Fabric is stored for long time.
Barrie Mark/Patta: Causes: Yarn package is either hard or soft. Lot Mixing of yarn. Improper yarn tension. Uneven yarn dyeing.
Slub: Causes: Excessive ply during yarn production. Improper machine setting (Blow Room, Carding, Ring Frame).
Wrong Design: Causes: Wrong insertion of yarn during knitting. Wrong setting of fabric design in knitting machine.
Lycra out: Causes: Lycra tears out during running the machine for production.
Thick & Thin: Causes: Diameter of yarn is uneven i.e. yarn irregularity. Variation of yarn tension in course wise direction.
White Specks/ Dead Cotton: Causes: If fiber is immature. Fabric construction contains dead fiber/ damage fiber.
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Crease mark: Causes:
More cycle time. Faulty plaiting device. Slack on tight selvedge causes crease at an angle to each selvedge. Incorrectly set bowed-expander. Compacting is done when fabric is in folded condition. Variation of heating and cooling rate. Improper fabric movement.
Physical Laboratory Tests Color Fastness to wash Test: This test measures the resistance of fading of dyed textiles when exposed to daylight.
A Typical recipe to measure the color fastness to wash:
Sodium Perborate-1 g/l Tetra Acetyl ethylene Diamine-0.15 g/l ECE Phosphate-4 g/l M:L-1:50 Temperature- 600 Celcius for ISO-105-C06 Temperature-400 Celcius for ISO-105-C08
Machineries Specification: Name: Rota Wash Machine Model: M228 No. of steel balls: 25
126
Picture of Rota Wash M228 Required Instruments of color fastness to wash Test Procedure: There are instruments which are required to determine color fastness to wash. They are-
Rota Wash machine Stainless steel ball Multifibre Fabric Grey Scale Sewing Machine Color Mtching Cabinet
Working Procedure of color fastness to wash Test
127
Sample collection and conditioning Making a specimen of 10x4 cm Sewing the specimen with multifibre fabric Making solution of 4 g/l ECE detergent anmd 1 gg/l Sodium Perborate (0.15 g/l TAED when required) Put the specimen with multifibre fabric on Rotawash Set the temperature to 600 celcius and time 30 minutes Rinsing with hot water Squeezing with cold water Drying at around 600 celcius Stiching isd broken except one end Measuring of staining and color change in Grey scale Assessment of Color Fastness to Wash: Grading
Color Fastness
Grade-5
Excellent
Grade-4
Good
Grade-3
Fair
Grade-2
Poor
Grade-1
Very Poor
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Color Fastness to Perspiration Test: This test measures the resistance of fading of dyed textile when exposed to human sweat. A Typical recipe to measure the color fastness to perspiration:
Sodium Di-Hydrogen Phosphate (Acid)-2.2 g/l Di-Sodium Hydrogen Phosphate (Alkali)-2.5 g/l Sodium Chlorite-5 g/l (Used in both acid and alkali pot) L Histidine Monohydro Chloride-0.5 g/l (Used in both acid and alkali pot) Distill water Lactic acid
Machineries Required: Machine Name: Binder Working Procedure of Color Fastness to Perspiration:
129
Collect the sample from bulk
Conditioning at least 4 hours
Cut a specimen in size 10 x 4 cm
Attach same size multifibre with specimen
Prepare acid and alkali solution an d check PH (Acid 5.50 and alkali 8.00)
Immerse the sample in acid (Alkali glass rod (1:50) for 30 minutes Place the sample with multifibre in preheated perspirometer glass plates with pressure of 12.5 KPa Place the perspirometer in woven for 4 hours (Temp-370 celcius) Remove the perspirometer from woven and remove the sample from perspirometer Dry at temperature not exceeding 600 Celcius
Conditioning at least 4 hours
Assessment with grey scale and test report making
130
Personal Safety: Use Hand Gloves Use Eye Protector Color Fastness to Rubbing: Definition: This test is designed to determine the degree of color which may be transferred from the surface of a colored textile to a specific Crockmeter test cloth for rubbing. (Dry and Wet state).
Rubbing Machine Features:
Name: Crockmaster 680 Manufacturer: James Heal Origin: UK Press 4 and 6 together for calibration. Complies with ISO-105-F09
ISO Crocking Cloth Features: Length x Width: 5x5 cm Fabric Type: 100% Cotton
131
Picture: ISO Crocking Cloth
Picture: Crockmaster 132
Working Procedure of Color Fastness to Rubbing:
Collect the sample from bulk Tense the fabric to its limit Put Newton weight on fabric sample Calibrate the machine Then stary rubbing according to buyer requirements Conditioning at least 4 hours
GSM: GSM is the term that determines the weight in grams of fabric for each N.R Group meter. In N.R Group knit fabric the following machine is used to determine the GSM.
Machine Features:
Machine Name: GSM Cutter Manufacturer: Antonio Brustio Criteria: GSM Measurement Origin: Italy
Working Procedure of determining GSM:
Put the fabric sample under the GSM cutter. Move the circular handle by putting and applying pressure. This will make the fabric get cut in a circular shape. Now, measure the weight of fabric sample. 133
Fabric Analysis via Burnout: Here in NRG Composite Yarn Dyeing Ltd., fiber analysis is done via burnout. Let’s have a deep see at the process: Take a fabric weighing 1 gram (Here, 60% cotton and 40% polyester combination was taken.
Prepare a solution of 80% Sulphuric acid
Dissolve the fabric sample into the solution
After 5 minutes, the cotton part will be eliminated
Now, the fabric is weighed up again
Thus, the the weight of cotton and Sulphuric sample was determined.
Resistance to Pilling Test: This test determines the formation of pills and other related surface changes of textile fabrics. In, SMFL three types of machines are available to determine resistance to pilling. They are1. Maxi-Martindale Pilling Machine 2. Impulse Pilling Machine 3. ICI Pilling Machine Now, The Maxi-Martindale machine is mostly used due to its easy application method and accuracy.
134
1. Maxi-Martindale Pilling machine Specification: Dimension: 670 x 320 x 890 (Depth x Height x Width)
Electrical Requirements (Single Phase): 85-264 Volts No. of specimen: 09 RPM: 47.5+-2.5 Working pressure on test specimen: 2.5 CN/cm2 Origin: UK Manufacturer: James Heal Weight: 80 Kg Woven Felt Diameter: 140 mm/ 90 mm ISO: 12945:2
135
Picture: Maxi-Martindale Pilling Tester
Different Parts of Maxi-Martindale Pilling Test machine:
Woven Felt Fabric Weight Table Spindle Campaign Mechanism
2. Impulse Pilling Machine Technical Specification:
Picture: Impulse Pilling Tester
Standard: ASTM D3512 Dimension: 300 x 520 x 500 mm (Width x Depth x Height) Weight: 35 Kg Power: 85-204 Volts
136
Air Supply: 2 Cubic feet/minutes Template size: 105 x 105
Running Time: 30 Minutes
ICI Pilling Machine Technical Features:
Weight: 39 Kg No. of boxes: 4 Rotation Speed: 30/60 rpm Power: 220 volts Template size: 125 x 125 mm Origin: UK Manufacturer: James Heal Body: Steel, Box Surface: Rough Polyurethane Pipe: 140 x 31.5 x 3.2 mm (Length x Diameter x Thickness)
Working Procedure of Pilling Test (All Three in One Flow chart):
137
Collect the sample from bulk
Conditioning at least 4 hours
Cut the sample according to test procedure
Sample size ICI: 125 x 125 mm, Maxi-Martindale: 140 mm Impulse: 105 x 105 mm
Place the sample in machine with required tube/felt/abradent/foam or filament
Set the machine according to buyer rerquirements
Remove the sample and assessment with pilling standard
Test report making
Assessment of Pilling Test: Grading
Resistance against Pilling
Grade-5
Excellent 138
Grade-4
Good
Grade-3
Fair
Grade-2
Poor
Grade-1
Very Poor Color Fastness to Water
Color Fastness to Water: Color fastness to water is designed to measure the resistance to water of dyed, printed, or otherwise colored textile yarns and fabrics. This method is to assess the degree of cross staining which may occur when garments are left in contact when damp. This test measures the resistance to water of any colored textiles.
Apparatus:
Perspiration Tester Oven Multi-Fiber Fabric Grey Scale Color matching cabinet Glass plate or Acrylic resin plate Glass beaker and stirring rod Weight applied: 5 kg Temperature: 370 Celcius
Reagent: Distilled water or de-ionized water is used in this test method because natural water is variable in composition. Working Procedure:
139
Collect the sample freom bulk Conditioning at least 4 hours Cut the specimen in size 10x4 cm Attach same size multi-fiber with specimen Immense the sample in distill water with glass rod (1:50) at room temperature Place the sample with multi-fiber in pre heated perspirometer glass plates with pressure of 12.5 KPa Place the perspirometer in oven for 4 hours Remove the perspirometer from oven and remove sample from perspirometer Dry at temperature not exceeding 600 Celcius Conditioning at least 4 hours Assessment with grey scale and report making
Assessment: Grading
Fastness Rating
Grade-5
Excellent
Grade-4
Good
Grade-3
Fair
Grade-2
Poor 140
Grade-1
Very Poor
Color Fastness to Dry Cleaning
Color Fastness to Dry Cleaning: This test measures the resistance of fading of dyed textiles when exposed to dry cleaning processes. Apparatus and Conditioning: 200 ml Perchloroethylene Undyed Cotton Twill Bag Rota Wash Machine without steel balls Working Procedure:
141
Collect the sample from bulk Conditioning at least 4 hours Cut a specimen size of 100 x 40 mm Prepare 100 x 100 mm cotton bag with three sides sewing Place the specimen with 12 steel disks in undyed cotton bag and shut the bag Place the bags with disks in the container and add 200 ml Perchloroethylene Start the machine and set 30'x300 Celcius Remove the sample from cotton bag and absorbent paper of cloth Drt at temperature not exceeding 600 Celcius Conditioning at least 4 hours Assessment with Grey scale
Assessment of Dry Cleaning Result: Grading
Fastness Rating
Grade-5
Excellent
Grade-4
Good
Grade-3
Fair
Grade-2
Poor
142
Grade-1
Very Poor
Color Fastness to Light
Color Fastness to Light: This test measures the resistance of fading of dyed textiles when exposed to sunlight. Apparatus:
Distill Water Light Box Conditioning Room Blue Wool Xenon Test chamber
Working Conditions: Temp-630 Celcius Humidity-30% Time-20 hours
Working Procedure:
143
Collect the sample from bulk Conditioning at least 4 hours Cut the specimen in size of 10 x 4.5 cm Set the test sample into a cardboard Set the Blue Wool into another cardboard Place the specimen with blue wool in Xenon test chamber M/C configuration: Temp-630 Celcius, Humidity-30%, Time-20 hours Remove the sample from Xenon Chamber Conditioning at least 4 hours Assessment with grey scale and test report making
Assessment of Color fastness to Light Procedure
144
Grading
Light Fastness
Grade-8
Outstanding
Grade-7
Excellent
Grade-6
Very Good
Grade-5
Good
Grade-4
Moderate
Grade-3
Fair
Grade-2
Poor
Grade-1
Very poor
Phenolic Yellowing
Phenolic Yellowing: It determines the resistance of textile from getting yellowed because of many reasons.
Tools for Phenolic Yellowing:
BHT free polythene Adhesive tape Conditioning room Perspirometer
145
Picture: Control Fabric
Picture: Control Paper
Working Procedure of Phenolic Yellowing: Collect the sample from bulk
Conditioning at least 4 hours
Cut a specimen in size 100 x 30 mm
Each specimen and control fabric individually placed between a test paper in half folded
Prepare a sandwich with one control fabric, 05 sample, 06 test paper and 3 glass plates
Wrap up with 03 layers BHT free polythene and sealed with adhesive tape
Place the sandwich in perspirometer with pressure of 12.5 KPa
Place the perspirometer from woven and remove sample from perspirometer
Assessment without conditioning and immediately with Grey scale
Yest reporty making
146
Assessment of Phenolic Yellowing Result: Grading
Rating
Grade-5
Excellent
Grade-4
Good
Grade-3
Fair
Grade-2
Poor
Grade-1
Very Poor
Brusting Strength Brusting Strength: Brusting Strength defines the ability of a textile fabric to withstand pressure. Here in SMFL, for measuring the brusting strength of a fabric, TruBrust2 machine is used.
Machine Introduction and Specification:
Picture: TruBrust2 Machine
147
Name: TruBrust2 Origin: UK Manufacturer: James Heal Area: 7.3 cm2 and 50 cm2 Maximum applied force: 1100 KPa/ 160 PSI
Working Procedure:
Collect the sample from bulk Conditioning at least 4 hours Cut 05 specimen perfectly Sample size not less than 500 mm Place the samle on the machine with required diameter Start the machine and record figure Start the machine for correction (Without sample) Record figure and test report making
PH Test of Fabric: 148
Instruments and Apparatus and Technical data:
Machine Name: Wise Shake RPM:70 Specimen: 2 grams Time: 2 hours 100 ml distilled water 5 mm sample size Buffer solution (4.0, 7.0, 10.0)
Test Procedure:
Collect sample from bulk
Conditioning at least 4 hours
Cut 20 grams specimen in size 0.5 mm and 0.05 grams
Place the specimen into glass stopper flask
add 100 ml distill water (1:50) and check PH
Place the specimens into the mechanical shaker for 2 hours
Remove the flask from mechanical shaker and calibrate PH meter Assessment with PH meter and test report making
149
Lab Dip Preparation While training in N.R Group Knit Fabrics Ltd. we prepared the several lab dip and match with the standards by the spectrophotometer. The preparation and matching with the standards is described below:
150
Washing Procedure:
151
For Dark Shade (above 3.0)
152
153
Test for Mercerizing: Necessary Equipment: Volumetric flask Beaker Burette Pipette Measuring flask Electric balance Shaker Scissors Necessary Chemicals: Barium hydroxide, Ba(OH)2 0.25(N) Hydrochloric acid, HCl, 0.1(N) Water Methyl Orange Sample: Yarn sample → 58/2 s singed and mercerized Single mercerized fabric → Grey mercerized, Yarn count – 58/2s , Speed –10m/min. Double mercerized fabric → Grey mercerized, Yarn count – 58/2s, Speed -10m/min. Stock solution preparation: To prepare 0.25(N) Ba(OH)2 Solution from a hydride barium hydroxide powder following formula should be applied:
154
155
N ow dissolve this Ba(OH)2 in to 250 ml distilled water. K eep the solution overnight in a safe position in a volumetric flask
Procedure: 2 gm of mercerized sample (fabric or Yarn) has to taken The sample has to immerse in 30 ml 0.25(N) Ba(OH)2 solution. The sample in immersion under Ba(OH)2 solution should keep 4 hrs After 4 hrs the sample mercerized cotton should remove from the solution and shaken carefully and well by a shaker. From the left out solution 10 ml has to take for titration. The solution is titrated with 0.1 (N) HCl in presence of methyl orange indicator. The volume of HCl required to titrate the Ba(OH)2 solution has been recorded. Now the mother/stock solution of Ba(OH)2 also titrated with same HCl and the amount has been recorded. Then can be calculated by the following formula,
Ba(OH)2% absorbed by the mercerized sample =
156
Chart:
Result: Ba(OH)2 % absorbed by the mercerized Yarn sample = 20.319% Ba(OH)2 % absorbed by the single mercerized fabric sample = 23.904% Ba(OH)2 % absorbed by the double mercerized fabric sample = 25.5%
Evaluation: Below 15% → Unmercerized Above 15% → Mercerized 70% → Fully mercerized So the samples are mercerized.
Remarks: The easy test done is not a standardize test. It is generally practiced in mills and factories for quicker evolution of mercerization. In this test accuracy is maintained as much as possible. Titration is done manually. Moreover the concentration of HCl and Barium Hydroxide also measured by the same titration procedure. As the test result comes in a percentage basis the initial concentration variation does not hamper the test result. For this reason the test result is claimed accurate and satisfactory.
157
Chapter-09 Effluent Treatment Plant (ETP) & Caustic Recovery Plant (CRP)
158
NRG Composite Yarn Dyeing Ltd. is very much concern about its effluent, for this reason they established two effluent treatment plant and they are ETP-I (capacity1200 m3 per day) & ETP-II (capacity 3000m3 per day). The ETP in NRG is a biological one. Here bacterial and protozoa are the catalyst of biochemical reaction to convert the toxic material into environmental friendly gases and substances. The initial cost of biological ETP is more but it has a low running cost if control is greater.
Reaction Time: 8-12 hr for secondary treatment 50 m3/ hr for secondary treatment 3-4 ppm/30-35 c (for proper bacterial action) Quantity of micro-organism 1:4 Total capacity of ETP plant: 1200 m3 /day + 3000 m3/day = 4200 m3/day. Sludge removes level: 800 MI/ 1/2hr f
Effluent Analyzing Report:
159
Reference: USPEA (United States Environment Protection Agencies) IWRA (International Water Resources Association) GOB (Government of Bangladesh)
Typical flow diagram of a Physical-Chemical and Biological treatment Plant in N.R Group Knit fabric Ltd :
160
Equipments for ETP Laboratory:
HACH method (for measuring BOD & COD) BOD Incubator Electric Shaker Reflex Condensat for COD measuring PH meter TDS meter Inhoff con for measuring sludge quantity Desiccators Separating funnel Electric Balance COD Reactor
Parameters of ETP:
Waste water outlet - 3000 m3/day Treatment capacity - 1500 m3/day Running cost - 2 – 4 Tk./m3 Plant capacity - 1200 m3/day Bacterial: Protozoa - 60:1 Sludge collection at - 60 – 70 % Screen allowance - 1 in2 PH - 6.5 – 8 Dissolved oxygen (DO) - 2 – 3 ppm Outlet water temperature - 30 - 35ºC Dwell time for effluent discharge - 48 hrs. (For oxidation tank)
Bacteria in oxidation tank
Protozoa
Bacilli
Paramecium caudatum
Cocehi
Euplotes
Beggiatoa
Vorticella dutrina
Spirillum
Colpidium
161
Biochemical Reaction:
Bacteria decompose the organic matter and other matters are related with oxygen by microbial action i.e. biochemical reaction and produce gases and free radicals. Metals are bio-chemically reacting with the enzyme and produces gases. Mn + O2
Enzyme
MnO2
Process Water Test Report:
Note: Sample Collection from Hanks Dyeing Area
162
Caustic Recovery Plant (CRP) NRG Composite Yarn Dyeing Ltd. is very much concern about the environmental issues. Here a large volume of caustic both liquid and solid used in different wet processes as a basic chemical. In case of Yarn and Fabric Mercerization most of the liquid caustic produced and effluent containing caustic produced. The recovery of these caustic of 2º to 5º Be concentration is beneficial for cost minimization and reduction of effluent which may cause environmental hazard.
Few Parameters: Inlet steam pressure 7 – 8 bar Vacuum condenser pressure 0.3 – 0.4 bar Condenser temperature 70ºC - 75ºC, Pressure 2 bar, Flow 60lit/80sec Weak lye temperature 35 - 37ºC, Concentration 5-6ºBe Strong lye temperature 75 ºC - 85ºC, concentration 28 30ºBe 1st stage: o Shell side steam pressure 1.2 – 1.6 bar o Shell side temperature 120 – 130ºC o Pipe temperature 110 – 115 ºC 2nd stage: o Shell side temperature 110 ºC o Pipe temperature 90 – 100 ºC 3 rd stage: O Shell side temperature 85 -100ºC oPipe temperature 70 - 85ºC 163
164
Shhematic diagram of Caustic Recovery Plant
165
Recovery Process:
166
Rain Water Harvesting:
Rain water is collected here.
Remarks: NRG Composite Yarn Dyeing Ltd. is using 0-5deg (total) hardness water which is suitable very for dyeing. The underground water is free from hardness creating metals and eliminates the need for water treatment plant. The electricity supply system is very good and fluent. It is fully equipped to produce its necessary power. Its capacity of power generation is increasing with another two generators to be established. The constant pressure of water also eliminates the need for high rise water tank and maintains flow speed in different machines.
167
Chapter-10 Maintenance
168
MACHINE MAINTENANCE PROGRAM OF NRG Maintenance of Machinery: Maintenance of machinery is very essential mechanical effort for achieving smooth running of different machines. Maintenance is a process by which equipment is looked after in such a way that trouble free. Services and increased machine life can be ensured and specific product quality required by the customers is sustained. On time maintenance increase m/c lifetime & ensures trouble free services. In N.R Group Fashion Ltd. following two types of maintenance are done. Break down maintenance Preventive maintenance Maintenance System used in NRG:
YEARLY MAINTENANCE CHECK LIST Demag monorail hoist
Grease all the moving parts and bearings Check all the nut and bolts Check oil level Check each sprocket, chain and chain collector are ok Check the thickness of the lines Check visually the damage of main girders
Pressing machine Check rotating table balls and lubricate. Lubricate the axial bearings
169
Yarn singeing machine Clean control cabinet using a vacuum cleaner. Do not touch the circuit card and soldering joints. Every 4 year change the battery on the RAM card. Santex compactor machine Check the machine for visual damages. Replace the worm reduction gear oils. Check the compacting shoes for wearing. Check the blankets for wearing. Check the foundation bolts of the machine Fabric dyeing machine Check the machine for visual damages. Drain & replace the main pump bearing oil. Drain & replace the oil of gearboxes. Check and if necessary replace all plaiter bearings balls. Check the platter/ J-box center alignment Check the manhole O-ring. Check and grease all greasing points. Check and tight all plaiter, catch basket, reel and other support bolts from theinside of the machine. Check all the PTFE carbon supports and sleeves in the plaiting device systeminside the machine Santex compactor machine Check the machine for visual damages. Replace the worm reduction gear oils. Check the compacting shoes for wearing. Replace if necessary. Check the blankets for wearing. Check the foundation bolts of the machine. Dornier mercerizing machine Grease all the bearings and moving parts. Check the bearing bolts and replace them if necessary. Change the gear oil of the gear boxes Check the rubber coating of the fixation & drive rollers Complete check of the cooling plant Check the spray rings, piping and armatures
170
Check the pneumatic piping for proper connection Check and retighten the electric connections of machine Replace the chains and the chain wheels of the drives
HALF YEARLY MAINTENANCE Alea hank dryer machine Adjust the chain tension and lubricate it Check the oil level of the gear box Change the gear oil once a year Lubricate the bearings with grease Calatorruckh inspection machine Lubricate chain and adjust the tension. Grease all the bearings. Change gear oil once a year. Precision winding machine Clean the cable channels and electric cabinet Clean the flyer set and displacement unit Check certain Every 5 year replace buffer batteries on the control cabinet Loris Bellini hank dyeing machine
Clean and check the compressed air filter. Check the pneumatic cylinders. Tightening of every bolt. Tightening of foundation bolts. Check and replace the roller bearings if necessary. Maintenance for piston pneumatic valves. Tightening of terminals of electric motors. Tightening of terminals of electric boards.
Yarn singeing machine Check condition of variator, remove any wound on thread. Check automatic contrails of all sensors.
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MONTHLY MAINTENANCE CHECK LIST Assembly winding machine Check the cone holder's looseness Clean the inverters Clean the yarn path properly Check the package diameter sensor Jaeggli yarn mercerizing machine Grease hooks draught bearings. (B) Grease function bearings of the squeegee roller (H) Grease fulcrum bushes of the lifting cylinder(L) Check the hydraulic oil pressure Loris Bellini hank dyeing Inspection of wear and tear of lid gasket Lubricate the electric motors. Check the mechanical seals of add pumps Inspect the serviceability of safety valves. Maintenance of stuffing box Yarn singeing machine Check spindle motor supply Check function of the vacuum monitor of the suction off switch. Check function of the compressed air monitor on the gas mix section Scholl package dyeing Check main pump v- belt connection Check the safety, steam and water valves Hydro extractor machine Lubricate the spindle bearings at the end of the shaft and greasing nipple on the rotary treble behind the front part of removable casing. Lubricate the guide pulley behind the front part of removable casing. Mahlo setter and compactor Check, Grease if necessary: Nuts of width adjustment spindles for wear Check all spindle bearings for free running Free running of guide rollers, deflection rollers and contact rollers. Pressure springs of chain pensioner Perform visual inspection: Gear box oil level Belts, pulleys Move width adjustment motor to the end position & check counters
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Corino slitting machine Grease the squeeze for the rope fabric part Grease the dewatering bearings Grease the bearings of water slitting device & driving screw for basket opening Grease the bearings of open width squeezer Change gear oil once a year Sclavos fabric dyeing machine Check the main pump oil level. Check all bearings, seals, gaskets. Check all mechanical seal flush pipes. Discharge the water from air filter. Check all m/c flange & platform bolts. Grease RCR rotary joints every 2 weekly Clean & check the control panel. Check the adjustment of catch basket mechanism and plaiter system
FABRIC DYEING MACHINE Check the machine for visual damages. Check the main pump bearing oil level. Replace the oil. Check the operation of all alarms. Check and clean the sedo master controller. Clean the inlet filter of magnet level indicator. Check the pressure & temperature gauges. Check and grease all greasing points. Check all mechanical seal flush pipes. Specially check the plaiter water nozzle. Santex compactor machine Grease rotary joints. Grease heated rollers supports bearings. Grease all the bearings. Grease all the transmission chains.
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WEEKLY MAINTENANCE CHECK LIST Stalam yarn dryer Clean the dryer by compressed air Clean the foreign matters in the inductor and between electrode Clean the filter of asplirator air intake Hydro-extractor Remove all the centrifugal heads & check Clean the entire machine Lift the c over & clean the drain cannel. Lubricate the rotary table behind the front part removable casing. Yarn pressing machine Check the joints for tightness. Check the foundation bolts Check pneumatic oiler oil level Scholl package dyeing machine
Flange connections checked for tightness. Open outlet of V68 valves and clean. Open outlet pipe after V, 38 valve and clean. Check lip seal & clean grease with PROBA 270( kluber) Upper side of cams on lid ring treated with lubricant. Use molykote graphitegrease. Checked oil level in atomizer
Monfortspadder, stretcher & dryer machine Perform visual inspection & clean In feed roller control unite cylinders Guide rod. guide roller & bearings Lifting device cylinders bearings Under liquor squeeze roller adjustment Teflon coated bearings, immersed rollers
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Belt tension, gear unit Universal joint shaft coupling Width adjustment functional wheels Selvedge sensor uncovers. Pinning shoes. brush Never grease graphite chain guide rails Brushes after pinning Clean & oil Filter housing & replace. Sprockets. Clamps with E Sliding guides cylinders Dryer removable screens Air suction control butterfly valves Oil level of pneumatic oiler filter
Yarn singeing machine Cleaning the burner rings. Cleaning the root blower suction air filter. Clean the traveling blower. Dornier mercerizing machine Visually check the motors and pumps Check the chain drives and tension of chains Check that all the expanders are properly adjusted Check the & readability of the expander rollers. Clean the machine from fluffs, dirt, chemicals Check the function of the solenoid valve Check the function of the cooling plant, Check the spraying nozzles and clean them if blocked Check the rubber coating of the drive rolls
surface
Corino slitting machine Check turntable tire pump & spring pressure. Grease the turntable. Check de twister speed reducer, transmission belts pneumatic brake. Check oiler oil level of the fabric expander. Check movable reel plaiter driving system.
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Fabric dyeing machine Check the main pump oil level. Check all bearings, seals, and gaskets. Check all mechanical seal flush. pipes. Discharge the water from air filter. Check all m/c flang& platform bolts. Grease RCR rotary joints every 2 weekly Clean & check the control panel. Check the adjustment of catch basket mechanism and plaiter system.
Corino squeezer machine Clean the machine rollers with wet cloth.. Check visually all bearings & drive chains. Check all air and water hose joints. Clean compressor filter. Check tyre pump bellow the turntable. Check and clean fabric spreader. Check tension of trapezoidal belts. Grease turntable- bearing balls Santex compactor machine
Clean the machine properly. Check all bearings & chains. Check all mechanical joints. Check all the machine alignments. Top up the compressed air lubricant. Clean the panel A/C properly. Check tension and wear of the spreader belt pulleys.
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DAILY MAINTENANCE CHECK LIST DORNIER MERCERIZING MACHINE
Check the quantity of fresh caustic soda in the caustic soda storage tank. Check the complete machine and the auxiliary equipment visually. Check whether all chains, chain wheels and drives are properly running. Check the soda temperature to ensure that the cooling plant works properly Check that all rollers are easily relatable.
ETP WEEKLY Clean the glass electrode of pH meter. Check the filter net of dosing pump. Check the current of air pressure.
Clean air filter of blower (monthly).
EVERY 4 MONTH Calibrate the PH meter with buffer solution, 7 & 4. Calibrate the blower meter, Grease the oxygen meter. Grease the scraping, bridge, bridge wheel of ball bearing. EVERY 2 YEAR
Grease the spring ball bearing. Change the oil of sludge transfer pump. Change the oil of feed pump. Change the oil of lifting pump. Change the oil of sludge blower. Change the sensor of oxygen blower (if necessary). Change the electrode of pH meter (if necessary). Change the oil of dosing pump.
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Chapter-11 Utility Services
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Utility Facilities Available: The following utility facilities are available at NRG Water. - Steam. - Electricity. - Gas. - Compressed air.
Description of the Utilities Water: Raw water hardness: 18-20 0 (Generally 30 ppm) Boiler water hardness: 0 0 M/c used: Water conditioner Submergible pump : 2 (For NRG) & 1 (For Dormitories) o Process water: 200m3/hr and 150 m3/hr o Domestic use: 150 m3/hr Company: Cleaver Brooks Country of origin: USA. Water consumption: 4500-5000m3/day Water pressure: 6-6.5 bar Steam:
oiler Steam: 10.2 tons/hr. & 2.3 tons/hr. B Steam pressure: 7.5-8 bar Steam temp: 150-160 0 C M/c used: Fire tube type Gas Boiler & Exhaust Gas Boiler Piece: 02 (Fire tube type Gas Boiler) & 01 (Exhaust Gas Boiler). Capacity: 10.2 tons/hr. & 2.3 tons/hr.
Power Supply: Supply: Self M/c used: Electricity Gas Generator Brand: Cater Pillar Origin: USA Piece: 05 Total Capacity: 5.6 MW (1 MW+1 MW +1 MW +1 MW+1.6 MW).
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Chiller:
Air Compressor:
Piece: 07 Brand: BOGE (No. of machine 6) & ROLL AIR (No. of machine 1). Country of origin: Germany Capacity: 6 m3 /hr.
Cooling Tower: Use in: Generator Country of origin: Thailand Piece: 12 Source of Utility: 1. Water- Own supply (Pump) 2. Steam-Own supply (Boiler) 3. Electricity-Generator & PDB 4. Gas- Titas Gas Transmission & Distribution Co. Ltd. 5. Compressed air- Own supply (Air compressor)
Remarks: NRG Composite Yarn Dyeing Ltd is using 0-5deg (total) hardness water which is suitable very for dyeing. The underground water is free from hardness creating metals and eliminates the need for water treatment plant. The electricity supply system is very good and fluently. It is fully equipped to produce its necessary power. Its capacity of power generation is increasing with another two generators to be established. The constant pressure of water also eliminates the need for high rise water tank and maintains flow speed in different machines. 182
Chapter-12 Store & Inventory Control
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Inventory System for Raw material: In NRG Composite Yarn Dyeing Ltd there are different inventory systems for different raw materials. Grey Fabric Store: All the grey fabrics are stored in the fabric store near the batch section. Different types of fabric are listed in the sheet according to fabric types, quantity and consumer's requirement. Dyes and Chemicals: There is a different store for dyes and chemicals. Vanes types of dyes and chemicals are stored here according to dyes and chemicals companies. Different types of dyes and chemicals are listed in a sheet. In the sheet the stored quantity of dyes and chemicals are also included. Every day the sheet is updated and a copy of this sheet is supplied to the dyeing manager, dye house and lab section. Spares: In NRG Composite Yarn Dyeing Ltd required amount of spears of different machines are stored in the mechanical store room. All the spares are listed in a sheet which is controlled by the mechanical & maintenance personnel. Spares are arranged in the store room according to their size, quantity & requirements. There are shelves in the store room to keep the small spare parts. Finished Goods: NRG Composite Yarn Dyeing Ltd supplies its finished dyed fabrics to its garments section. So, dyed finished fabrics are stored for short time in the finishing section. All the delivered fabrics are noted on the tally khata according to the lot no, quantity, fabrics diameter, buyer's name, Color & considering other technical parameters.
Remarks: NRG Composite Yarn Dyeing Ltd has individual stores for raw materials, finished goods etc. the store of dyestuff & chemicals are not so clean. There is no enough space to store the finished goods. It requires increasing the store area.
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Chapter-12 Conclusion I have completed our industrial attachment successfully by the grace of Allah. Industrial attachment sends us to the expected destiny of practical life. The completion of the two months Industrial attachment at N.R.G. Composite Yarn Dyeing Ltd. we have got the impression that factory is one of the most modern export oriented composite complex in Bangladesh. Though it was established only a few years ago, it has earned “very good reputations” for its best performance over many other export oriented textile mills. During our training period, talking with the clients of this mill we knew that the mill is fulfilling the country’s best export oriented white finished fabric as well as very good colored fabric due to its modern machinery & good management system. Mill is settled with utility to give all convenient supports to the productions for twenty-four hours. It had self-power generator system to satisfy total power consumptions of the mill. We are enough fortunate that we have got an opportunity of having a training in this mill. During the training period we are received co-operation and association from the authority full & found all man, machines & materials on appreciable working condition. All stuffs & officers were very sincere & devoted their duties to achieve their goal. Finally we would like to wish N.R.G. Composite Yarn Dyeing Ltd. to have a blast & thanks to administration of NR GROUP Ltd. for their cordial attitude to us.
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