Cotton is selected by considering the following points.
i) Fibre length, fineness, strength influences yarn strength & spinning value.
ii) Short fibre content, fineness influences on Regularity of yarn.
iii) Maturity and fineness of cotton determine neps generation at different stages,
iv) Trash % in the cotton -indicate- no of beating points treatment necessary in blow room.
II. Fibre quality Index '(FQI) = lusm / f
Where
l u = product of 2.5 % span length in mm and uniformity
Ratio %(u) measured on digital fibrograph divided by ICC
s = Bundle fibre strength in g/tex at 3mm gauge
length. measured on stelometer.
m = maturity co-efficient determined by sodium hydroxide swelling technique,
f = fibre fineness or micronaire value (micro games/inch) FQI is a measure to assess the quality characteristic of the cotton required for spinning different counts with desired CSP values.
III. CSP ( Count Strength Product) = (310-count) √ FQI
IV. Maturity Co-efficient= (M + 0.6H + 0.4I)/100
V.
Where, M,H and I are % of mature. Half mature and immature fibre respectively (Determined by standard sodium hydroxide
swelling technique)
vi) Fibre propensity for imperfection = trash % x short fibre % divided by Micronaire value
It is a useful tool in the selection of cotton for minimizing . the imperfections in the yarn and it should be maintained below : 16.
Continue to write the article 1.12 - fibre properties -
consideration for the selection of cotton.
