The weight of all textile materials varies with the variations in the relative humidity of the surrounding atmosphere in which they are kept. The variations in the weight of different textiles are different. Therefore, the normal practice in the trade is to have the conditioned weight of textiles as the basis of the purchase or sale of textiles. Conditioned weight is the weight of a textile material when all the moisture from it has been removed by drying in a special type of woven (i.e woven dry weight) and then adding standard moisture regain which is different for different textile materials. The count of yarn calculated from the conditioned weight is called the conditioned count. In this article, we will discuss a calculation of conditioned cotton and yarn.
Different Formulas of “Conditioned Cotton and Yarn” Calculation with Examples
The following formulas will be used during calculating conditioned cotton and yarn.
1. Moisture Regain,
…..Original weight – Ovendry weight
= ………………………………………………….. × 100%
……………..Oven dry weight
2. Conditioned weight or corrected invoice weight = Ovendry weight + standard moisture regain%
3. Moisture content,
…..Original weight – Ovendry weight
= …………………………………………………… × 100%
………………….Original weight
4. Conditioned count in tex,
…..Ovendry weight in grams + standard moisture regain%
= ………………………………………………………………………………….
……………………Length of yarn in kilometer
….Conditioned weight in grams
= …………………………………………..
…………Length in kilometer
The standard moisture regain of cotton is 8.5% and its standard moisture content is 7.83%.
Example 01:
Calculate the conditioned count of 500 meters of cotton yarn in tex, if its oven-dry weight is 10 grams.
Solution:
500 meters,
……..500
= …………..
……1000
= 0.5 kilometer.
Now, Conditioned weight of yarn,
= 10 + 8.5%
…..10 × 108.5
= ……………….
……….100
= 10.85 grammes.
Therefore,
Conditioned count of yarn,
……Conditioned weight in grams
= ………………………………………………
………….Length in kilometer
…….10.85
= ……………..
………0.5
= 21.7 tex.
So, the Conditioned count of yarn is 21.7 tex.
Example 02:
Calculate the conditioned count of 20 kilometers of cotton yarn, if its oven-dry weight is 800 grams.
Solution:
Conditioned count in tex,
….Oven dry weight in grams + standard moisture regain%
= ………………………………………………………………………………….
……………………Length of yarn in kilometer
…..800 + 8.5%
= …………………
……….20
…….868
= …………..
……..20
= 43.4 tex.
So, the Conditioned count in tex is 43.4 tex.
Example 03:
Calculate the moisture regain, moisture content, and conditioned weight of 100 grams of cotton yarn, if it’s woven dry wet is found to be 94.5 grams.
Solution:
Moisture Regain,
…..Original weight – Ovendry weight
= ……………………………………………………. × 100%
……………….Ovendry weight
…..100 – 94.5
= ………………… × 100%
………..94.5
……5.5
= ………. × 100%
….94.5
= 5.82%
So, Moisture Regain is 5.82%.
Again,
Moisture content,
…..Original weight – Ovendry weight
= …………………………………………………. × 100%
………………….Original weight
…..100 – 94.5
= ………………… × 100%
…………100
= 5.5%
So, the Moisture content is 5.5%.
Therefore,
Conditioned weight of in grammes,
= Ovendry weight + standard moisture regain%
= 94.5 + 8.5%
= 102.53 grammes
So, the Conditioned weight of cotton is 102.53 grams.
Author of this Article: Mayedul Islam Assistant Chemist Ha-Meem Group, Tongi, Gazipur, Bangladesh Email: [email protected]