International Journal of Engineering Inventions
Guideline for Achieving Yarn Quality
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| 4.1.6 Guideline for Achieving Yarn Quality
For producing high quality yarn, there is need of high standard raw material. Hence 70 to 80 % of basic yarn quality is decided by raw material cotton. There is a direct relationship between certain quality characteristics of fiber and yarn. Short fiber content is very important for producing yarn quality; 4 to 5 mm of fiber length is lost during processing. Fiber having 12 to 15 mm don’t contribute to strength but only the fibers more than this length contributes to produce positive characteristics in the yarn. Fiber length should be more than 28 mm. This fiber length effects on yarn strength and yarn uniformity. End breakage also depends upon fiber length. For better yarn quality fiber length should be more than 28 mm. Micronaire (fiber fineness) value should be 3.8 to 4.2. If micronaire is coarse, this always results in lower strength and lower elongation. Cotton having stickiness should not be used. If cotton is sticky then it is better to reduce the percentage of sticky cotton in mixing. For such kind of cotton there is need of low humidity and high temperature. Cotton with less contamination should be used. Process requirement for Blow room by quality point of view: If micronaire value is low, then process parameter of blow room becomes very critical. After blow room process the neps increase in cotton. In case of increasing the neps, the beater speed should be reduced instead of feed roller to beater setting. Fiber rupture should be less than 2.5 percent. Blow room setting should be set in such a way that the draft in cards is same for all the cards and the variation in feed density is as low as possible. If trash percentage in cotton is less and number of neps in the sliver is more than at this stage, reduce the beating point. 3 beating points should be more than enough. [43] tải về 1.28 Mb. Chia sẻ với bạn bè của bạn:
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