How can you measure yarn irregularity?
Mainly two methods are used for measuring yarn irregularity.
- Capacitive method (Uster evenness tester)
- Optical method (Zweigle G580)
What is irregularity in yarn?
The irregularity or unevenness of a yarn is commonly deﬁned as the variation in ﬁneness along its length and more appropriately as the variation in mass per unit length along the yam’. It is expressed as U% or CV%.
What is a yarn measure?
Fabric, material typically produced by weaving, knitting or knotting textile fibers, yarns or threads, is measured in units such as the momme, thread count (a measure of the coarseness or fineness of fabric), ends per inch (e.p.i) and picks per inch (p.p.i).
What do you think about the impact of yarn irregularity?
The uneven one should have more thin regions than the even one as the result of irregularity, since the average linear density is the same. Thus an irregular yarn will tend to break more easily during spinning, winding, weaving, knitting or any other process.
What is yarn testing?
Yarn test methods that are used when values such as tenacity, elongation or shrinkage are determined. Test room conditions. Linear density. Breaking force and elongation at break.
What is limiting irregularity?
The limiting irregularity of yarn is the minimum count variation expected from ideal yarn with a random fibre ends distribution. … Wool fibres exhibit diameter variations both between fibres and within fibres. Ignoring the within-fibre diameter variations may lead to an underestimation of yarn limiting irregularity.
What is yarn imperfection?
Imperfections can be defined as the total number of neps, thick and thin places in a given length of yarn. … A yarn with more imperfections will exhibit poor appearance grade, lower strength and poor performance in weaving is likely to produce fabric with low quality.
What is CV in yarn?
The variation of the yarn count (CV count) is the variation from one bobbin to the other. If this variation is more than 2% the difference in the fabric is visible with bare eyes. … In general the lower the C.V.% the better is the measured value of the yarn.
How yarn count is measured?
Yarn count refers to the thickness of a yarn and is determined by its mass per unit length. It is usually measured by the number of grams per one kilometer of yarn, a unit of measure called “Tex”.
How do you measure yarn denier?
Denier is the weight of yarn mass in grams and is measured by weighing 9,000 meters of yarn. Yarn with a higher denier has more mass per unit length than one with a lower denier. Providing two yarns are made of the same kind of material, the higher denier size, the larger the thread or yarn size.
What is importance of yarn evenness?
Yarn evenness deals with the variation in yarn fineness. Thisis the property, commonly measured as the variation in mass per unit length along the yarn, is a basic and important one, since it can influence so samy other properties of the yarn and offabric made from it.
What is yarn fault?
Yarn faults The defects of yarn is called Yarn faults. When an uneven place or impurities or any other lack of minimum quality is found in a yarn is called yarn defects or faults. … An abnormally thick place or lump in yarn showing less twist at that place.
How do you calculate yarn count for CV?
The formula is CV% of doubling = CV% of single / √n where n = no. of doublings 1.8 = CV% of single / √6 CV% of singles = 4.41% Ana i.e. CV% of comber sliver is 4.41%. 17. Two roving having 7.8 CV% are fed in to the ring frame making yarns and ring frame adds CV% 4.8 then what will be the final yarn CV%.