Yarn Count Numbering System

Yarn Count Numbering System
Rana Sohel
Executive Engineer
Sunman Textile Mills Ltd. Chittagong
Cell: +8801912-420118
Email: rsohel07tex@gmail.com





Count
Count is the numerical expression which expresses coarseness or fineness of yarn. It means that, the yarn count refers how much a yarn is fine or course. We also can say that the yarn count number indicates the length of yarn in relation to the weight.

But according to the Textile Institute, they define yarn count as “Count, a number indicating the mass per unit length or length per unit mass of a yarn”.

Yarn count is also known as yarn number or linear density.

System of Count Numbering
Different system or units are used to measuring the yarn count or yarn number which mostly depends on the material used for preparing the yarn and the area where it was manufactured.

Count numbering system can be grouped as following categories;
  • Analytical System &
  • Instrumental System.
Analytical System
Actually this process is consisting with some other systems based on several calculations and this is why it is called Analytical system. The systems are including;
  1. Direct System &
  2. Indirect System
Direct System
In this process the count is based on the number of weight units in a length unit. Thus the size or bulkiness of the yarn is directly proportional to the count number. A coarser yarn will have a higher count number while a finer yarn will have a lower count number.The system is used for very fine and very coarse yarns. This system is mostly used for silk, jute etc.

We can work in this system by following categories;
  • Tex
  • Denier &
  • Jute Count
Tex
It can be defined as the weight present in 1000 meter of yarn in grams where length of yarn is fixed. It means that, for example, if there is a 1000 meter of yarn and have a weight of 20gm then the yarn count will be 20tex. Because tex refers the weight in gram of unit length.

Here is the equation for determining the yarn count in Tex;


              Weight in grams
Tex = ………………………
          Length in 1000 meter

                Sample weight in gm X Unit length (1000m)
Or, Tex = ………………………………………………
                          Sample length in meter

An extra qualification of Tex system we know that it is known as the universal process of yarn count which is introduce by International Standard Organization (ISO) with several textile scientists, technologists and manufacturers.

Denier
It is defined as the weight of yarn thread in grams presented in per 9000 meter length of that yarn. It is just like about Tex system only has to change the unit length from 1000m to 9000m and then the equation of denier becomes as;

           Sample weight in gm X Unit length (9000m)
Den = ………………………………………………
                     Sample length in meter

As an example we can say about 454 meter of yarn containing 5 gram of weight then the count in Den will be

           6 X 9000
Den = …………
               454

= 118.9 den

Jute Count
The weight of yarn of 1 lb present in 14400 yds length of yarn is known as jute count or pounds per spindle.

Indirect System
In this system the count of yarn expresses the number of length units in one weight unit. Higher the count finer is the yarn. This system is generally used for cotton, worsted, woolen, linen (wet spun), etc. The indirect system covers the majority of the important types of yarns. The count is based on the number of length units in one weight unit

This is also having some sub-system as following;
  • Cotton Count
  • Metric Count &
  • Worsted count.
Cotton Count
Actually by the term cotton count can be defined as the number of hanks of 840 yds presented in 1 lb weight of yarn. This is also known as British or English count. It is denoted by Ne

The equation of cotton count measurement is as following;

                   Length in hanks of 840 yds
Count, Ne = ……………………………
                           Weight in lbs

              Sample length in yds X unit weight
Or, Ne = ……………………………………
              Sample weight in lbs X unit length

Now for an example, if we consider a yarn sample of 2000 yds with a weight of 0.08 lb then the cotton count will be

                      2000 X 1
Count, Ne = ……………
                    0.08 X 840

= 29.7 Ne

Metric Count
Metric count is express 1000 gm or 1 kg weight of yarn can contains how many numbers of hanks of 1000 meter. It is denoted by Nm.

The formula of measuring metric count is;


                               Sample length in meter X unit weight
Metric Count, Nm = ………………………………………
                                 Sample weight in kg X unit length

For example, if we consider a yarn of 2000m having the weight of 450g. So the count in metric system will be

                                   2000 X 1
Metric Count, Nm = ………………
                                 0.45 X 1000

= 4.4 Nm

Worsted Count
It is the number of hanks of 560 yds presented in 1 lb weight of yarn is known as worsted count which is widely used for yarn composed by wool.

Instrumental System
By this process count of yarn is measured by using different sorts of instrument where any kind of calculation is not needed and we can get directly the yarn count. The machines which are mostly used of count measurement are given bellow;
  1. Beesley Balance
  2. Wrap Reel Balance
  3. Quadrant Balance
  4. Stubb Yarn Balance
1. Beesley Balance:
When a cotton yarn is supplied in short length or removed from fabric, the count of yarn can be measured by a special type of balance is called Beesley’s balance.
Beesley Balance
Beesley Balance
2. Wrap Reel Balance
By this standard method of count testing, the count of any type of a yarn can be calculated. In this system yarn is measured by the wrap reel counter. In case of cotton, the circumference of wrap reel is 1 yd and required yarn is 120 yds. Again in case of jute, wrap reel circumference is 2.5 yds and required yarn is 300 yds.

3. Quadrant Balance

Quadrant balance is one type of typical balance. This is direct reading instrument. The count can be directly measure from quadrant balance.

4. Stubb Yarn Balance

Stubb yarn balance is also worked on the basis of fixed length & fixed weight as like a Beesley balance and it is used to find the count of fabric sample. Here the number of fixed weight yarn gives the count of yarn.
 
 

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