Yarn Numbering System (Yarn Count) | Direct Count System | Indirect Count System

Yarn Count:
Count is a numerical value, which express the coarseness or fineness (diameter) of the yarn and also indicate the relationship between length and weight(the mass per unit length or the length per unit mass)of that yarn. Therefore, the concept of yarn count has been introduced which specifies a certain ratio of length to weight.

The fineness of the yarn is usually expressed in terms of its linear density or count. There are a number of systems and units for expressing yarn fineness. But they are classified as follows .

Types of Yarn Count:

1. Direct Count System 
2. Indirect Count System

1. Direct Count System:
The weight of a fixed length of yarn is determined. The weight per unit length is the yarn count! The common features of aII direct count systems are the length of yarn is fixed and the weight of yarn varies according to its fineness.

The following formula is used to calculate the yarn count:

N= (W×l) / 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 length of the sample 

In brief, definition of the above Systems is as follows:

1. Tex system ..........................NO. of grams per 1000 meters
2. Denier .................................No. of Grams per 9000 meters
3. Deci Tex ..............................No. of grams per 10,000 metres
4. Millitex ................................No. of milligrams per 1000 metres
5. Kilotex............................... .No. of kilograms per 1000 metres.
6. Jute count........................No. of lb per 14,400 yds

The Tex of a yarn indicates the weight in grammes of 1000 metres yarn. So that 40Tex means 1000 meters of yarn weigh 40gm.

From above discussion it is concluded that, higher the yarn number(count) coarser the yarn and lower the number finer the yarn.

2. Indirect Count System:
The length of a fixed weight of yarn is measured. The length per unit weight is the yarn count. The common features of all indirect count systems are the weight of yarn is fixed and the Length of yarn varies according to its fineness.

The following formula is used to calculate they are count:
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 length of the sample
w = Unit of weight of the sample. 

1. Ne: No of 840 yards yarn weighing in One pound

2. Nm: No of one kilometer yarn weighing in One Kilogram

The Ne indicate show many hanks of 840 yards length weigh one English pound. So that 32 Ne Means 32 hanks of 840yards i.e.32x840 yards length weigh one pound.

For the determination of the count of yarn, it is necessary to determine the weight of a known length of the yarn. For taking out known lengths of yarns, a wrap-reel is used. The length of yarn reeled off depends upon the count system used. One of the most important requirements for a spinner is to maintain the average count and count variation within control.

Yarn Count Variation:
The term count variation is generally used to express variation in the weight of a lea and this is expressed as C.V.%. The number of samples and the length being considered for count checking affects this. While assessing count variation, it is very important to test adequate number of leas. After reeling the appropriate length of yarn, the yarn is conditioned in the standard atmosphere for testing before it's weight is determined.

How to Find Yarn Count from GSM

Yarn Count from GSM:
If we want to job in garments then we need to know this things.

Like we need to make a single jersey Fabric. But we didn't know the fabric count. Some people say through experience like you can use 26/28 count of yarn. It’s depend on experience. But if you want to know perfectly then you need to know the tricks. Before going to tricks, we should know what is count and GSM? 
 
Definition of Yarn Count:
Yarn count is a numerical value which refers to the coarseness or fineness of the yarn. It is calculated by taking into account the length and weight of the yarn. The weight of the yarn is just the mass per unit length of the yarn.

Definition of Fabric GSM:
Fabric GSM refers to the Grams per Square Meter of the fabric. It is the weight of the fabric per square meter, measured in grams.

Example: Single jersey fabric is 130 GSM. Now find the yarn count?

Ans: For single jersey,

4300/GSM

= 4300/130

= 33.08

You can make this kind of fabric with 32/34 count of yarn.

Another System:

For single jersey,

(-0.141 x GSM) + 50.22

= (-0.141 x 130) + 50.22

= 31.89

So you can make fabric with 32 count of yarn.

I also add some others:

1. Terry = 6240 ÷ GSM
2. S/J = 4300 ÷ GSM
3. Pique = 5200 ÷ GSM
4. Fleece = 7200 ÷ GSM
5. Interlock = 7200 ÷ GSM
6. 1x1 Rib = 6000 ÷ GSM
7. Lacost = 5500 ÷ GSM
8. 2x2 Rib = 6250 ÷ GSM
9. Terry = 6240 ÷ GSM

Another Tricks:

1. S/J = (-0.141x GSM) +50.22
2. Pique = (-0.146 x GSM) +57.16
3. Double Lacost = (-0.167 x GSM) +64.36
4. 1x1 Rib = (-0.123 x GSM) +54.57
5. Interlock = (-0.206 x GSM) +80.56
6. Lycra 1x1 Rib = (-0.119 x GSM) +59.12
7. Lycra 2x2 Rib = (-0.108 x GSM) +56.62