Count is a numerical value that expresses the coarseness or fineness of the yarn and also types of Count indicate the relationship between length and weight. We can find the fineness of wool yarn using the count.
Table of Contents
Types of Count:
- Direct System-Tex, English, etc
- Indirect System- Wool etc
Calculation of Wool Yarn in Direct System:
Formula:
N=L ×w/W×l
Where,
N = Yarn count or numbering System
W = Weight of the sample at the official regain in the unit of the system
L = Length of the sample
l = Unit of the length of the sample
w = Unit of Weight of the sample
Woollen Count (DEWSBURY)
Unit of the length (l) =1Yard 1yard=0.9144 meter
Unit of the Weight (w) = 1 ounce (oz) 1 oz=28.350 gram
Woollen Count (YSW)
Unlit of the length (l) =256 Yards 1 pound=453.6 gram
Unit of the Weight (w) = 1pound(lb) 1meter=1.0936 yard
Example 1.1
What length of yarn is contained in 1.2kg of Wool yarn 30?
Solution:
We know that,
N=L ×w/W×l
where,
N=30
W=1.2 kg=1200 gram
l=256 yards=256×0.91 meter=232.96
w=1 lb =453.6gm
L=?
L=l ×WN/w
L=232.96×1200×30/453.6
=18,486.507 meters.
Example 1.2
How long will it take for a winder to wind 3 lbs of 18 wool yarn if the winder operates at 550 yards/min with an efficiency of 95%?
Solution:
We know that,
Time, t=Length/Speed
t=L/V
Here,
L = Length of yarn in the package
Speed, V=580yd/Min
Weight of the Yarn W=3 lbs
Yarn Count Ne = 18
Unit of Length l=256 yards
Unit of Weight w=1 0z
We know that,
Yarn Count,= Ne=L ×w/W×l
L=l ×WN/w [1 oz =28.350 gram]
L=2563×453.6×18/28.350
=221,184 yards
t=221184/580
=381.35 min ( No breaks)
Therefore, t=381.35/0.95
=401.42 minutes
Another formula for Indirect System
NR=N/n
Where NR = Ply or resultant Count (Nm, Ne)
N=Single Yarn count
n = Number of yarns in the ply
Example 1.3
A ply consists of 2 single yarns, each having a count of Nm 60
Solution:
Ply Count NR=N/n
= 60/2=30
Prosenjit Paul
B.Sc In Textile Engineering
Shahid Abdur Rab Serniabat Textile g Engineering College, Barishal
prosenjittex7@gmail.com
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