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Overview of a Knit-Dyeing Factory with Necessary Productionformulas Global Journal of Researches in Engineering: G Industrial Engineering Volume 14 Issue 1 Version 1.0 Year 2014 Type: Double Blind Peer Reviewed International Research Journal Publisher: Global Journals Inc. (USA) Online ISSN: 2249-4596 & Print ISSN: 0975-5861 Overview of a Knit-Dyeing Factory with Necessary Production Formulas By Md. Tanjin Amin Bangladesh University of Engineering and Technology, Bangladesh Abstract- Different processes associated with complete production of fabrics are discussed briefly in this paper. An effort is made to formulate all the production steps. This paper also gives an idea of different processes and machineries used usually in a fast growing and mass productive knit-dyeing factory. Major processes in all machines are discussed briefly. Different important parameters in different machines are also stated here. This paper tries to gather all the information related to knit-dyeing factory shortly. A helpful estimation of machine capacity for required production amount can be perceived from this paper. Also the existing efficiency of different processes can easily be calculated from different mathematical formulas stated here. Keywords: hanks, knit-dyeing, gsm, mercerization, yarn count. GJRE-G Classification : FOR Code: 2 0 01, 2 0 02 OverviewofaKnitDyeingFactorywithNecessaryProductionFormulas Strictly as per the compliance and regulations of: © 2014. Md. Tanjin Amin. This is a research/review paper, distributed under the terms of the Creative Commons Attribution- Noncommercial 3.0 Unported License http://creativecommons.org/licenses/by-nc/3.0/), permitting all non commercial use, distribution, and reproduction inany medium, provided the original work is properly cited. Overview of a Knit-Dyeing Factory with Necessary Production Formulas Md. Tanjin Amin Abstract- Different processes associated with complete II. Knitting production of fabrics are discussed briefly in this paper. An effort is made to formulate all the production steps. This paper In a fabric processing industry, fabric also gives an idea of different processes and machineries manufacturing starts with knitting process. Knitting is the used usually in a fast growing and mass productive knit- process by which yarn turns into fabrics. Knitting is of dyeing factory. Major processes in all machines are discussed two types- circular knitting and flat knitting process. 2014 briefly. Different important parameters in different machines Knitted fabrics consist of a series/row of loops, popularly are also stated here. This paper tries to gather all the Year known as stiches. These loops are arranged according information related to knit-dyeing factory shortly. A helpful to predetermined designed pattern according to the estimation of machine capacity for required production 9 amount can be perceived from this paper. Also the existing type of fabrics. A new loop is pulled through an existing efficiency of different processes can easily be calculated from loop during the progression of series. Active loops are different mathematical formulas stated here. held by the needles of knitting machine. When a new Keywords: hanks, knit-dyeing, gsm, mercerization, yarn loop comes to the needles, previously active loop is count. released and the new loop becomes the active loop. This loop forming process goes on and thus fabrics are I. Introduction formed continuously. A sinusoidal wave form is angladesh’s first growing economy is the blessing observed in needle movement during fabric formation in of textile & clothing industries. The economy of circular knitting process. Needles move in circular Bangladesh was dependent on agriculture solely. knitting process while needles remain in fixed position in B I I Version XIV Issue But after the introduction of textile sector, the scenario flat knitting process. Carriages with yarn move in flat has changed dramatically. The economy of Bangladesh knitting process. Yarn may be grey colored or other is no longer dependent on agriculture. The agriculture colored. Grey color is the basic color which comes from Volume based economy has been shifted to textile based rapidly spinning mills. But different yarn colors can be achieved G & massively. Now Bangladesh earns near about 80% of by yarn dyeing process. Fiber dyeing is also applied to () its foreign revenue from this sector. Cheap labor has achieve colored yarn. Single jersey, double jersey/rib made it easier to spread textiles based industries. More and interlock structures are the main three types of than 5.7 million of people are working in this sector now. circular knitted fabrics. Plane single jersey, lycra single Most of them are women. This sector is helping women jersey, single lacost, double lacost, honeycomb pique, to be self-reliant. This short brief on the scenario of designed interlock, single jersey fleece, rib, lycra rib, textile sector shows how much importance it bears for waffle, pin rib etc. are the main derivatives of these three the economy of Bangladesh. Knit-dyeing factory is the types structure. Flat knitting is done to produce collars second phase of textile factories. Spinning mills are the and cuffs which are mainly rib or interlock structures. first phase and garments are the last phase. But very Birdseye, Solid, Tipping, Two Part, Two Part Stripe, Researches in Engineering few of Bangladesh population know about the Welted etc. are the main derivatives of rib and interlock production procedure in a knit-dyeing factory where designs in the flat knitting. of nal fabrics are produced actually. Different production a) Production Calculation Approach in Circular Knitting our formulas are also unknown to most the persons No of Needles = (π * Machine Diameter in Inch associated to this sector. So, an effort is made here to * Machine Gauge) make all known about the fabric forming process with Weight of Produced Fabrics = [(No of Needles J Global mathematical models. It will surely help those who * Machine RPM * Stitch Length in Meter * No of experience the processes; but hardly know the Feeders * Machine Running Time in Minute * Machine calculative approach. Efficiency * n) / (1.094 * 2.2 * 840 * No of Counts)] kg n= 1 for Single Jersey Fabrics n=2 for Rib / Interlock Fabrics • Sample Calculation Author: Department of Mechanical Engineering, Bangladesh University Given Data: of Engineering and Technology, Dhaka, Bangladesh. e-mail: [email protected] Machine Diameter = 26 Inches ©2014 Global Journals Inc. (US) Overview of a Knit-Dyeing Factory with Necessary Production Formulas Machine Gauge = 24 Needles per Inch hours, washed, and re-dipped. This procedure is Machine RPM = 26 repeated several times. Once the desired color is achieved, the yarn is steamed to fix the dye to the fibers. Stitch Length = 2.65 mm Because it does not use as many chemicals as other No of Feeders = 84 forms of dyeing, hank dyeing is less damaging to the No of Counts = 30 material. The final dye colors are also usually richer than Machine Running Time = 8 Hours those achieved by other dyeing methods. In hanks dyeing, a batch usually requires 14 Machine Efficiency = 85% hours. So, the capacity of a hanks dyeing machine can n = 1 be estimated in below formula. No of Needles = (π * 26 * 24) Average Production Capacity = (Batch Loading = 1960 Capacity * Machine Efficiency * 24 / 14) kg/day . If a 90% efficient machine has capability of Weight of Produced Fabrics = [(1960 * 26 * 2014 dyeing 245 kg yarn in each batch, average production 0.00265 * 84 * 480 * 0.85) / (1.094 * 2.2 * 840 * 30*1) will be 378 kg/day. However this formula gives idea Year Kg = 76.31 Kg about average production estimation only. In some Machine diameter means the diameter of the cases, nearly 20% more or less production can be got 10 cylinder used in the machines. Needles are attached in depending on the colors of the yarn. this cylinder. Machine gauge means the number of needles in an inch of cylinder. 840 yards of yarn b) Package Dyeing constitute 1 hank. The number of hanks required to Package dyeing usually denotes for dyeing of make 1 pound weight of yarn is called the yarn count. any type yarn wound on the compressible dye springs/perforated solid dyeing tubes or cones. Yarn b) Production Calculation Approach in Flat Knitting dyeing in package form is done at high temperature and ue I Version I ue I Version Weight of Produced Fabrics = [(No of Needles s under high pressure, with the packages mounted on * Maximum Carriage Speed (m/s) * Stitch Length in hollow spindles .These spindles are fixed on the dyeing Meter * No of Feeders * Machine Running Time in carriers, which is inserted into the dyeing vessel after Seconds * Machine Efficiency) / (1.094 * 2* 840 * No of closing the lid of the machine, the dyeing liquor is forced Counts * 2.2 * n)] kg through the packages in two way pattern (inside to out n = 1 for Single Jersey Fabrics and outside to in) and goes on circulating throughout Volume XIV Is Volume n = 2 for Rib or Interlock Fabrics the vessel and yarn. Heat is applied to the dye liquor to achieve the dyeing temperature, time –temperature and G • Sample Calculation () flow reversal are controlled automatically. Once full Given Data: exhaustion is brought about, the carrier of colored yarn Maximum Carriage Speed = 1.2 m/s is consequently removed from the vessel. Considerable Stitch Length = 4.0 mm reduction in yarn handling, automatic & accurate dyeing No of Feeders = 12 possibilities, reduction in liquor ratio, uniform circulation of liquor, faster dyeing process etc. have given No of Counts = 30 advantage to package dyeing process over hanks Machine Running Time = 8 Hours dyeing process. Fig. 1 shows package dyeing process. No of Needles = 1120 * 2 Researches in Engineering Machine Efficiency = 85% n = 2 Weight of Produced Fabrics = [(1120 * 2 * 1.20 * 0.004 * 12 * 8 * 3600 * 0.85) / (1.094 * 840 * 30 * 2.2 * 2)] kg = 26.04 kg Global Journal of Journal Global III. Yarn Dyeing Yarn dyeing is the process by which colored yarn is obtained.
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