How to calculate the length of yarn on Yarn Package/Cone

1. Specific Objectives:

In this article, we will discuss the testing method to calculate the length of yarn on yarn package/yarn cone.

2. Introduction:

Yarn count refers to a numerical number that indicates the thickness and diameter of a yarn. However, it is not possible to determine the diameter of the yarn in any meaningful way.   Therefore, to determine the fineness of a yarn, the weight of a specific length of yarn is determined, which gives an estimate of a yarn count by a numerical number. This quantity is known as the linear density of yarn.

3. Materials and equipment:

The following instruments and materials are required for the measurement of yarn count.

·   Electronic ring wrapping reel machine

·   Yarn creel stand

·   Cotton yarn package/Yarn cone

·   Empty paper cone

·   Electronic Weighing balance

·   Calculator

4. Procedure:

1. First, we will collect the 5 different yarn packages/cones from the textile testing lab. 
2. Then, the Yarn cone/package is placed in the creel section of the electronic ring wrapping reel.
3. According to the standard, the yarn lea length should be 120 yards for correct evaluations of cotton yarn count otherwise, the incorrect result is achieved.
4. A ring wrapping reel has a girth size of one yard, thus 120 revolutions are given to the ring wrapping reel to get 120 yards of cotton yarn lea.
5. At least 10 samples of yarn lea were taken from the ring wrapping reel machine.
6. Then put yarn lea one by one on a weighing balance and note the weight of each lea sample in grams.
7. Average results of 10 yarn lea samples are taken in this practical so that accurate results are achieved.
8. After finding out the average lea weight, the English cotton count of cotton yarn is calculated with the help of the following formula;
9. $\mathrm{English} \mathrm{Yarn} \mathrm{Count}=\frac{64.8}{\mathrm{Lea} \mathrm{weight} \mathrm{in} \mathrm{gram}}$
10. Then the length of yarn on the yarn package/cone is calculated by using the following formulae;

Yarn Length on Cone (Meter)= Yarn Count (Nec) × Yarn Weight (lbs) × 840/ 1.0936

5. Application and Try Out:

After completing the above-mentioned test procedure, the obtained data is put in the following table for the calculation of yarn length in meters on yarn package/cone.

Table 5.1: Yarn count calculation

Sr. No.	Yarn Cone Weight (A)	Empty Paper Cone Weight (B)	Total Yarn weight on Cone (A-B)	Total Yarn Weight in Pound	Average Lea Weight	Yarn Count	Yarn Length on Cone
	(Gram)	(Gram)	(Gram)	(lbs)	(Gram)	(Nec)	(Meter)
1	897	63	834	1.84	3.24	20	28266
2	1092	63	1029	2.27	8.1	8	13949
3	658	63	595	1.31	1.62	40	40249
4	235	63	172	0.38	0.81	80	23350
5	413	63	350	0.77	2.16	30	17743

      

6. Safety Precautions:

• The length of yarn lea should be accurately measured.
• Yarn lea length should be 120 yards.
• The weight of yarn lea should be accurately measured.
• The weighing balance must be calibrated.
• The yarn count calculation should be accurate.

 7. FAQs:

1. What is the objective of yarn length measurement?
2. What is the girth size of an electronic ring-wrapping reel machine?
3. How many lengths of yarn lea sample is required to measure the yarn count?
4. How to calculate the linear density of cotton yarn?
5. How to calculate the yarn length on the cone in a meter?
6. What is the formula for yarn length on a cone (meter)?

 Author:

Engr. Muhammad Usman Ashraf

HOD Textile Department at TEVTA Punjab, Pakistan

M.Sc Textile Engineering (NTU, Faisalabad)

Email: usmanashraf884@gmail.com