# Textile Calculation

Problems and solutions of textile

## Important Measurement Point for Determining Fiber Quality

Some Important Measurement Point for Determining Fiber Quality
Amit Kumar Das
Founder of "টেক্সটাইল ম্যানিয়া" Blog
Pabna Textile Engineering College, Pabna, Bangladesh
Cell: 01770 456240
Email: amitptec6th@gmail.com

In yarn manufacturing, its very important to know or determine fiber qualities. Because the lion share cost of yarn manufacturing goes to raw materials. So attaining a quality garments its very argent to dignify raw material’s qualities. Thats why we have some specific measurement points by which we can specify actual yarn quality. Some of them are given below with small description.
 Cotton fiber bell
1. Uniformity Ratio:

Mean fiber length            100
Uniformity ratio = …………..……………. × ………
Upper half mean length         1

Mean length is the average length of all fibres approximately ¼’’ and longer,and upper half mean length is the estimate of the lengths of fibres in the upper half portion as measured by the fibrograph.

Rating of cotton fibres with respect to uniformity ratio

 Uniformity Ratio Rating Above 80 Uniform 76-80 Average Uniform 71-75 Slight irregular 70 and below Irregular
Coefficient of Variation (CV):
CV is relative measure of the length variation.The larger the value, the greater the variation in fibre lengths, and, conversely the smaller the value, the more uniform are the fobre lengths.

Rating of cotton samples with regard to fibre length variation

 CV% Rating Below 27 Low variability 27-34 Average variability 35 and above High variability
Fibre Fineness rating in micrograms/inch:
 Fibre Fineness Rating Very fine Below 3.0 Fine 3.0 to 3.9 Average 4.0 to 4.9 Course 5.0 to 5.9 Very course 6 and above
Maturity ratings:
 Rating Maturity Ratio Very mature Above 84% Mature 77 to 84% Average 68 to 76% Immature 60 to 67% Very Immature Below 60%
Fibre strength rating in 1000lbs. per square inch:
 Rating Strength rating in 1000 lbs. Superior 93 and above Very superior 87 to 92 strong 81 to 86 Average 75 to 80 Fair 70 to 74 Weak Below 70
Effect of short fibre in yarn:
 For good spinning 14% short fibre is accepted as allowable Short  fibre% 8% 13% 15% Break Factor 1904 1723 1620 Elongation 8.3 7.8 7.2 Break per 100 32 52 54.8 Spindle hourse