Question 53 (Textile Technology & Fibre Science)
A 50 tex yarn with mass CV of 12.5 % is produced from staple polyester fibres each of 4.5 denier fineness. The index of irregularity of the yarn, (rounded off to two decimal places), is __1.25__.
[Show Answer]
write here
Given:
Fineness of yarn=50 tex
=9*50 (Denier=9*Tex)
Fineness of yarn=450 denier
Mass CV(CVeffective)=12.5%
Polyester fibre fineness=4.5 denier
Formula:
Index of irregularity=
Where, CVlimit= (For polyester yarn)
Where, n is number of fibres in the yarn
n=count of yarn/count of fibre
n=450/4.5
n=100
CVlim=
CVlim=
CVlim=
CVlimit=10
Index of irregularity=
=
Index of irregularity(I)=1.25 (Answer)