Loop forming is the basic operation to produce knitted fabric. Knitting is the construction of the elastic, porous fabric, created by interlocking yarns by means of needles. Faultsdefects in the knitted fabrics textile learner. In textile industry faults are frequently occurred and stitch length. In this study we have done study on knit fabric faults and their causes. After that the yarn is passed through the knitting machine where the yarn is converted into knitted greige fabric and it is wound in the roll form. A hole in a knitted fabric for example can turn up due to a variety of reasons.
Various defects in knitted fabrics affect the quality but spirality is the most common fault that affects the single jersey knit wear fabric. As knitting is the process of converting yarns to fabric, during the process defects like needleline, hole, yarn variation, lycra jump, oil stain, sinker mark and so on are appeared and because of these defects the rejection rate reaches to 7. If we categorized the defect than there will be two categories. Fabric inspection four point system textile study center. As knitting is the process of converting yarns to fabric, during the process defects like needle line, hole, yarn variation, lycra jump, oil stain, sinker mark and so on are appeared and because of these defects the rejection rate reaches to 7.
A defect of the knitted fabric is an abnormality which spoils the aesthetics i. Study on different types of knitting faults, causes and. The process sequence involved in textile knitting process is firstly the yarn is put into the knitting machine creels. The loop length is an important quality control factor in the production of knitted fabric. Knitted fabric defects and remedies by jahanara enam 9. In view of this the present work aim to minimize the knits defects that mostly arises like needleline, hole, lycra break, oil stain, sinker mark, knit fly.
Causes of fabric faults due to knitting almost all the defects appearing in the vertical direction, in the knitted fabrics, are as a cause of bad knitting elements. Knitting defects free download as powerpoint presentation. Common fabric defects and its causes what is defect. It has influential impacts on stitch density, fabric weight, panel length, tightness, fabric width and dimensional stability brackenbury, 1992. Spirality in knitted fabric omics publishing group. Product category work wear wws ce classified garments are not included.
Three types of defect critical defect a defect that is likely to result in a hazardous or unsafe condition for an individual or anyone around him using the product or that contravenes mandatory regulations. The system must be clearly stated and ofeasy to execute. These inspectors have to detect small details that are. There are various types of defects which occur in the knitted fabrics out of which majorly found defects like hole, knit. This is a void in the warp direction due to yarn breakage. Many types of fault may be found in knitted fabric due to many reasons. A study on knit fabric faults and their causes daffodil international. List of fabric defects woven, knitted, terry and velvet. Study on different types of dyeing faults, causes and. For that reason knitted fabric manufacturer always try to produce their fabric defects free, but several defects may occur in the products process. Major defects of knitted fabric textile merchandising. We know that, fabric is the main raw material in the manufacturing process of garments.
These types of faults decrease the total quality of the knit fabric which ultimately creates a significant impact on the profit percentage. Top 10 sewing patterns for jersey and knit fabrics. 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. Pilling refers to the forming of little matted balls on the surface of knitted fabrics. Depending on the direction in which the loops are formed, knitted fabrics may be broadly categorized into two typeswarp knitted fabrics figure 12a and weft knitted fabrics figure 12b. Study on different types of dyeing faults, causes and remedies of knit fabrics md. At the core of any grading system is simplicity and accuracy.
Pdf study on different types of knitting faults, causes. If fabric rolls containing more than 40 points per 100 yards square are considered second. Definition of knitting knit fabric manufacturing process. Appendixi 303 fabric defects following are the additional fabric defects and their related theory. If fabric rolls contains less than 40 points per 100 yard square are considered first quality and as an acceptance criteria. To name a few breakage of needle during knitting, faulty yarn, lack of machine maintenance or even improper storage conditions can lead to holes. Identifying defect causes of weft greige knitted fabric. Still, some defects can have a variety of underlying causes associated with them. In textile industry faults are frequently occurred and stitch length has a direct effect on these faults. Pdf study on different types of knitting faults, causes and. The production of terry fabrics is a complex process and is only possible on specially equipped.
Top 10 sewing patterns for jersey and knit fabrics the. Knitting is the construction of an elastic, porous fabric, created by interlocking yarns by means of needles. Yarns spun from staple fibers contain imperfections, which can be subdivided into three groups. Minimization of defects in knitted fabric svkms nmims. Friends and family members apart from being sources of defects also viewed my work from time to time. The study of fine gauge knitted fabric defects during the six months showed that fabric nonquality is linked to three main sources. The production of terry fabrics is a complex process and is only possible on specially equipped weaving machines. Faults of knit fabric observed in textile industry. By controlling the loop stitch geometry and density, a wide variety of knitted. In textile industry, a lot of faults observed in knit fabric from its manufacturing process to dyeing finishing which are totally unexpected.
A defect in the knitted fabric is an abnormality, which spoils the aesthetics i. 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 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. 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. Normally fabric roll containing 40 points per 100 square yard are acceptable. A fabric roll 120 yards long and 46 inch wide contains following defects. Then the greige fabric is inspected for any faults or defects.
Hosiery yarns are soft twisted, in comparison to the warp yarns. Common fabric defects and its causes textile school. A list of commonly used knitted fabrics and its construction are explained. There are different types of defects found in knitted fabric, but the defects of knitted fabric is less than woven fabric. Fabric checker should know common defects found in fabrics and he must recognize defects on the fabric at the time of fabric inspection. 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.
Some defects such as those linked to yarn can be detected before knitting and avoided when an adequate control is applied to yarn. Single jersey fabric is mostly used for tshirts, sports wears and under garments, so. So, a textile engineer should have sufficient idea about all. Detection and classification of defects in knitted fabric structures. Most defects arising in the production process of textile products are still detected by human inspectors.
Fabric defect, causes and remedies toh problem kya hai. Here some frequently occurring faults in knitted fabric are given below. Knitted fabrics figure 12 are created by intermeshing loops of yarns using knitting needles leong et al. A defective portion in the fabric marked by distortion or cutting of warp and weft. Defect is the thing occurs in the fabric which makes the fabric or the finished product unacceptable to the desired quality level. There are various types of defects, which occur in the knitted fabrics of all types, caused by a variety of reasons. Use the hosiery yarns of the recommended tpm level for knitting. Faulty woven fabrics hampers the total quality of woven garments such as shirt, pant, trouser, jacket etc. In trade relationships between sellers of fabrics and their customers, a system of defect analysis or defect grading must be agreed upon and in use. Weavers tapping the fabric with the shuttle tip or pirn on the front rest when inserting a new pirn. Cross sectional size 30% to 60% of normal yarn with fault length of 4 to 25 mm. For this study, we collected different samples of common knit fabric faults. A defect of the knitted fabric is an abnormality which 3. As a textile engineer you should know about the major woven fabric faults which produced during woven fabric manufacturing.
Knitted fabric defects and remedies fashion2apparel. Fabric pull or the take down tension, on both sides of the grey fabric tube, on the knitting machine, should be equal. A fabric roll yard long and 45 inch wide contains the following defects. This is to certify the thesis entitled identifying defect causes of weft knit. In textile industry, woven fabric is produced by interlacing warp and weft yarn.
These faults occurred sometimes due to defective parts of machine, or sometimes due to use of defective raw materials. Quality control in the knitting process and common. This defect is caused by bunch of broken ends woven in the fabric. Detection and classification of weft knitted fabrics. The international standard describes defects which commonly appear during the inspection of knitted piecegoods. If youve made a few woven garments already then learning to sew with knits wont be as tricky as you think. Pdf minimization of defects in knitted fabric researchgate. There are various types of defects which occur in the knitted fabrics. A major defect is any defect that, if found in a finished fabric garment, would classify that fabric garment as a second rated. Some faults occur very frequently and some faults occur rarely. Knitted fabrics are produced by two general methods warp knitting, and weft knitting, and each method produces a variety of types of knitted fabrics. Uneven fabric take down tension, on the knitting machine. These are the faults that occur in range of the 10 to 5000 times per m of yarn.
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