Calculate Crimp Percentage of Woven Fabric
S. M. Hossen Uzzal
Production Officer
Monno Fabrics Ltd., Manikgonj
Email: uhossen@gmail.com
S. M. Hossen Uzzal
Production Officer
Monno Fabrics Ltd., Manikgonj
Email: uhossen@gmail.com
The crimp percentage is the difference between straightened thread length and the distance between the ends of the thread in the fabric.
Crimp % = (l-s)/s x 100
Measuring crimp practically is not always a simple procedure. The length of the crimped yarn may be easily measured, but to decide when the crimped yarn removed no longer retains crimp is not easy.
Where L is warp length, S is cloth length
Warp Length (L), L=(1+C)* S
Where C is crimp %, S is cloth length
Cloth length (S), S=L/(1+C)
Where L is warp length, C is crimp %
Problem-1:
A cotton cloth is analysed, and from a tested strip of 20cm, the mean warp length is 21.2cm. Determine both the crimp and take-up percentage.
Solution:
Crimp Percentage:
(21.2 – 20.0) / 20 = 6.0%
Take up Percentage
(21.2-20.0)/21.2 = 5.66%
N.B In many fabrics, there is not too great difference between the warp and weft crimps, but there are examples of quite large differences. E.g. in cotton poplin, the warp crimp could be 14% and the weft crimp in only 2%
Problem-2:
Calculate the length of warp required to weave 160m of cloth if the warp crimp is 12%
Solution:
S= cloth length = 160m
Crimp = S = 0.12 and therefore warp length will be:
C= (l-s)/s X100%; and c =l/s -1 and l =(1+c)*s
L= (1+0.12)*160 = 179.2m
Problem-3:
What length of cloth can be woven from 800m of warp if the warp crimp is 8%
Solution:
Warp Length, L =800m , find cloth length, S
S=L/(1+c) = 800/(1.08)
=740.8m