Two main causes of inconsistency that lead to fabric defects are raw material management before the knitting process and variation in parameters during the knitting process. In an experiment by yue 1993, three ends of 248 nm 125 tex worsted yarns are knitted into a plain jersey fabric with a 7gauge knitting machine. Knitting it is very natural that in the course of knitting fabrics, imperfections occur. For that reason knitted fabric manufacturer always try to produce their fabric defects free, but several defects may occur in the products process. Minimization of defects in knitted fabric svkms nmims. I would like to discuss about the major defects of knitted fabric. Astm d 5430 as per astm d 3990, standard terminology relating to fabric defects defects are named and identified for woven fabrics. A major defect is any defect that, if found in a finished fabric garment, would classify that fabric garment as a second rated. Normally fabric roll containing 40 points per 100 square yard are acceptable. Quality control in the knitting process and common knitting.
Appendixi 303 fabric defects following are the additional fabric defects and their related theory. Aug 14, 2012 normally fabric roll containing 40 points per 100 square yard are acceptable. If this roof is made from knitted fabric bi or multiaxial knitted. First, the laplacian pyramid is used to achieve the decomposition of original fabric image. The followings are common quality problems on knitted fabrics. Digital imaging is an adequate technique to determine the porosity of highporosity fabrics. Here some frequently occurring faults in knitted fabric are given below. To name a few breakage of needle during knitting, faulty yarn, lack of machine maintenance or even improper storage conditions can lead to holes. Gb2222838a gb8911193a gb8911193a gb2222838a gb 2222838 a gb2222838 a gb 2222838a gb 8911193 a gb8911193 a gb 8911193a gb 8911193 a gb8911193 a gb 8911193a gb 2222838 a gb2222838 a gb 2222838a authority gb united kingdom prior art keywords multi filament shd filaments process according prior art date 19880831 legal status the legal. Identifying defect causes of weft greige knitted fabric. Image inspection of knitted fabric defects using wavelet. Types of fabric defects with causes and remedies loom. Circular knitting machine, computerized jacquard machine, knitted fabric. Image inspection by wavelet packets and a neural network classifier is presented for nondefect and six kinds of defects in knitted fabrics.
To highlight the defective area in the fabric image, hu et al. Knitting is the construction of an elastic, porous fabric, created by interlocking yarns by means of needles. Fabric checker should know common defects found in fabrics and he must recognize defects on the fabric at the time of fabric inspection. We start by demonstrating the difference between woven and knit fabrics and then how knits are structured. A fabric roll 120 yards long and 46 inch wide contains following defects. The computer techniques are used in the processing of the defects images of weft knitted fabrics in this paper. Knitting defects free download as powerpoint presentation. The work demonstrated that changes occurring after laundering were largely due to alterations in the loop shape, rather than yarn or loop length shrinkage. Dec 11, 2015 for that reason knitted fabric manufacturer always try to produce their fabric defects free, but several defects may occur in the products process. Knitted fabric defects and remedies fashion2apparel. Realtime detection of knitting fabric defects using. This defect is caused by bunch of broken ends woven in the fabric. Different types of fabric defects with images fashion2apparel. Knitted fabric faults can also be detected by inspecting yarn input tension and loop but only few types of faults are concerned by these methods.
First, the fabric defects images are collected, and are pretreated in order to be seen more clearly. Pdf minimization of defects in knitted fabric researchgate. This paper has investigated the porosity of knitted fabrics using digital imaging techniques. There are various types of defects which occur in the knitted fabrics out of which majorly found defects like hole, knit. Knitting is the construction of the elastic, porous fabric, created by interlocking yarns by means of needles. It is acknowledged that nwct will provide a new way to detect warpknitted fabric defects automatically.
In textile industry faults are frequently occurred and stitch length has a direct effect on these faults. Dec 22, 2016 knitting machine settings related defects 11. A list of commonly used knitted fabrics and its construction are explained. Study on different types of knitting faults, causes and. Loop forming is the basic operation to produce knitted fabric. For brokenend defects on fabric surface, they obtained high detection rate. Apr 02, 2018 common fabric defects and its causes common defects of fabrics during manufacturing process includes back fabric seam impression, birds eye, bowing, broken colour pattern, colour out, colour smears, crease mark, drop stitching, dye streak in printing, hole, jerk in, knots, mixed yarn, mottled, needle line, open reed, pin holes, press off etc.
Still, some defects can have a variety of underlying causes associated with them. Specification measurement sheet bottoms and trousers, forms and data templates, 906. A grade is a numerical value given to fabric based on number, size and severity of defect seen during visual examination. Garment manufacturing process from fabric to finished product. Major defects of knitted fabric textile merchandising. Common fabric defects and its causes common defects of fabrics during manufacturing process includes back fabric seam impression, birds eye, bowing, broken colour pattern, colour out, colour smears, crease mark, drop stitching, dye streak in printing, hole, jerk in, knots, mixed yarn, mottled, needle line, open reed, pin holes, press off etc. A knitted fabric designer needs to understand the creative potential of knitting technology and work in partnership with available technology and technical expertise. You will learn the meaning of terms like knit and purl, wale and course and how a weft knit differs from a warp knit. Thin horizontal lines that appear at irregularly spaced intervals and are of various sizes 12. Knitted products find application field also among implants. The two classes of knitted fabrics are the filling knit and the warp knit. Application of knitted fabrics in technical and medical.
International journal on textile engineering and processes issn 23953578. Fabric inspection four point system textile study center. We will teach you about how knits are made and about the different types of yarns, so that when. Loom weaving different fabrics woven fabric remedies textiles loom home remedies textile art cloths. Our proposed system achieves the highest accuracy of 94.
The fabric is made of two sets of yarns, in which one set of yarn makes the pile, while the other set of yarn makes the base fabric. It refers that the product is unsafe or hazardous for the end user or violate mandatory regulations major defects. Knitted terry is pile jersey fabric made with a special attachment in regular circular knitting machines similar to woven fabrics. In 8, tsai and chiang considered the fabric images of oriented and nonoriented textures. The imperfections may be the result of faulty yarn, knitting machine malfunction or improper finishing. A defect is a fault that would reduce the expected performance of the knitted fabric or, if it appeared in a prominent position in an article made from the fabric, would readily be seen and rejected by a prospective. In a production process you may find there are several types of garments defects and if you want to avoid these defects then you have to know it which types of defects basically occurs. Weavers tapping the fabric with the shuttle tip or pirn on the front rest when inserting a new. Guo, in specialist yarn and fabric structures, 2011. The development of 3d knitted fabrics is based on 2d knitted fabrics. Compared with the traditional contourlet transform, wavelet transform takes the place of laplacian pyramid in nwct and the directional filter bank is nonsubsampled.
Article information, pdf download for image inspection of knitted fabric defects using. During loop formation the yarn breaks in the rejoin of the needle hook. Stitched garments are dispatched to finishing or washing department if washing is required. The defects in knitting construction are considered in terms of appearance and nature. A defect of the knitted fabric is an abnormality which spoils the aesthetics i. Introduction to under lap and over lap, closed lap and open lap. A defective portion in the fabric marked by distortion or cutting of warp and weft. For single jersey, pique and double pique, better shrinkage can be realized, 7%7% in general. There are different types of defects found in knitted fabric, but the defects of knitted fabric is less than woven fabric. They used different subbands of wavelet transform for finding the defects in fabric images. Loop length control which discusses other aspects like samples and experiments, results and discussion, conclusion of circular knitting machine, knitting. Identification of fabric defects on the machine knitted designs study knitting cycles of latch models on the machines 5.
Operators stitch and assemble garment components one by one and make the complete garment. Friends and family members apart from being sources of defects also viewed my work from time to time. Threedimensional knitted fabrics have been widely used in many fields, especially in technical textiles. Generally, due to loose structure, knitted fabrics have larger shrinkage than woven fabrics. There are various types of defects which occur in the knitted fabrics of all. Introduction to knit fabrics university of fashion. The processing of the defects images of knitted fabrics.
Yarn variation and lycra jump are achieved and these fabric defects need to be corrected to. Warp knitted fabrics construction 1st edition yordan. Weavers tapping the fabric with the shuttle tip or pirn on the front rest when inserting a new pirn. Images of six different induced defects were obtained and used in the analysis. Some faults occur very frequently and some faults occur rarely. Major defects can result in the product visual or performance failure, reducing its marketability or usability.
After cutting and printing process optional process, cut components are sent to sewing department. Pdf a fabric defect is any abnormality in the fabric that spoils the aesthetics i. Fabric is inspected to identify the severity and type number size location of defect. Knitting tools, knitted fabric quality, loop length. A new method for knitted fabric defect detection and classification using image analysis and neural networks is presented. The following chapter is an introduction to the fundamental principles relating to the design and manufacture of weft knitted fabric and fashion knitwear. Faultsdefects in the knitted fabrics textile learner. List of fabric defects woven, knitted, terry and velvet. Quality control in the knitting process and common. This lesson is the first in our 7part series on working with knit fabrics. At the time of sewing, garments are checked by quality checkers. Common quality problems on knitted fabrics zhenlihua. The types of defect include a hole, set mark coarse, d.
Fabric defects point values based on the following. Study on different types of knitting faults, causes and remedies of knit fabrics. In this paper, a nonsubsampled waveletbased contourlet transform nwct is applied in warpknitted fabric defect segmentation. Fill in and save specification measurement bottoms and trousers pdf form to your computer for easy archiving, emailing or printing. Defects are classified into following three categories. Defects in knitted fabrics, skew, bias, bowing, twisting, knots, thick yarn, thin yarn, uneven yarn structure, course yarn, slub, needle line, needle run, fabric run. Then the classification and the extraction of characteristic value of the defects are introduced on the basis of researching anglicizing of the pretreated images, and reaching the. Here we tried to make a list of six types of garments defects. We know that, fabric is the main raw material in the manufacturing process of garments. Pdf study on different types of knitting faults, causes. The loop length is an important quality control factor in the production of knitted fabric. Images of six different induced defects were obtained and used in the anal. Knitted fabric faults and their remedies slideshare. The aim of this book is to provide the background of the warp knitting patterning with a large amount of simulated 3d images of the structures, corresponding to the modern available tools for this.
There are various types of defects which occur in the knitted fabrics of all types caused by a variety of reasons. The warp knitted structures can have very complex architectures and very limited understanding exists. The production of terry fabrics is a complex process and is only possible on specially equipped weaving machines. A number of different methods have been proposed to determine the porosity of knitted fabrics, which include digital imaging, geometrical modeling, and air permeability. We will teach you about how knits are made and about the different types of yarns, so that. Human inspection by using knitted fabric inspection machines remains today the most used way to classify faults after knitting and after finishing 5. Detection and classification of defects in knitted fabric.
Brief description of tricot and raschel machines and fabrics lapping movement of. Second, the high frequency directional subband coefficients are extracted by means of the nonsubsampled. For changing the stitch length at same count at three same diametric double jersey knitting machine on same rib structure we found the effect of stitch length on common knit fabric faults. Pdf in this study we have done study on knit fabric faults and their causes. Introduction in todays very competitive market, it can be said that quality is the main factor in determining the success or failure of an organization. A defect is a fault that would reduce the expected performance of the knitted fabric or, if it appeared in a prominent position in an article made from the fabric, would readily be seen and rejected by a prospective purchaser. Many types of fault may be found in knitted fabric due to many reasons. Total defect points per 100 yard square are calculated.
In a flat piece, the yarn is raveled back and forth. Knitted fabrics and types list of knitted fabrics textile. If the yarn count is not correct on regarding structure, gauge, course and density. Image inspection of knitted fabric defects using wavelet packets. Realtime detection of knitting fabric defects using shearlet. By doing this study fabric defects like hole, lycra break and knit fly reduced by 26%, 36% and 41% respectively.
These faults occurred sometimes due to defective parts of machine, or sometimes due to use of defective raw materials. The fabrics had taken up their fully relaxed dimensions after five wash and dry. Abstractdiffering from the traditional contourlet transform, the nonsubsampled contourlet transform nsct is proposed to apply in warpknitted fabric defect segmentation. The fabrics had taken up their fully relaxed dimensions after five. Quality control in the knitting process the varied and diverse causes of fabric defects can generally be summarized in one word inconsistency. Appearance of holes in the fabric due to an interruption in a loop formation. Common fabric defects and its causes textile school. Application of knitted fabrics in technical and medical textiles. Determination of knitted fabric porosity using digital. It has influential impacts on stitch density, fabric weight, panel length, tightness, fabric width and dimensional stability brackenbury, 1992.
Knitted fabrics are produced by two general methods warp knitting, and weft knitting, and each method produces a variety of types of knitted fabrics. Composite polyester yarn for woven or knitted fabric download pdf info publication number gb2222838a. This is a void in the warp direction due to yarn breakage. Gb2222838a composite polyester yarn for woven or knitted. Knitted fabric defects and remedies by jahanara enam 9. In this paper, a nonsubsampled waveletbased contourlet transform nwct is applied in warp knitted fabric defect segmentation. The experiment demonstrates that nwct can achieve the positive segmentation regarding the common defects, such as broken warp, width barrier, and oil, and has excellent performance on these directional defects and regional defects. The types of defect include a hole, set mark coarse, dropped stitch, oil stain, streak, and tight end.
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