Determination of Metric count of cotton yarn by wrap reel and electric balance. Introduction:

Experiment No: 03

Experiment Name: Determination of Metric count of cotton yarn by wrap reel and electric balance.

Introduction:

Count:
Count is a numerical value which expresses the coarseness or fineness of yarn and also indicate the relationship between length and width.

There are two types of count:
(a) Indirect system. (English count, Metric count, Worsted count)
(b) Direct system. (Tex, Denier, Pound/Spindle)

Metric count:
It is defined as the number of hanks of 100m yarns present in 1 kg.

Objectives:

(1) To know about the number of count of cotton yarn.
(2) To know about the basic idea about metric count.
(3) To calculate the yarn fineness.
(4) To know about wrap reel and electric balance.
(5) To calculate the yarn smoothness.

Machine description:

(1) The wrap reel machine consists of a steel bar, handle and bobbin carrier.
(2) This machine is used to measure the length of yarn.
(3) The handle is used to rotate the wheel.
(4) Guide is used to give proper direction to the yarn.
(5) Electric balance is used to measure the weight.
Working principle:
(1) Firstly we will take a yarn and put it on the bobbin carrier and pass the yarn through yarn guide to the wheel of the wrap reel machine.
(2) Then we will rotate the wheel for 80 times.
(3) After 80 times rotating we will stop and take the yarn from the machine.
(4) Then we will measure the weight of that yarn with electric balance.

Table:

Observation no.	Sample length	Unit length	Sample weight	Unit weight	Yarn count	Average count
1.	120 yards	1093.6 yards	1.61 g	1000 g	68.15 Nm
2.	120 yards	1093.6 yards	1.64 g	1000 g	68.81 Nm
3.	120 yards	1093.6 yards	1.63 g	1000 g	67.31 Nm	67.32 Nm
4.	120 yards	1093.6 yards	1.65 g	1000 g	66.50 Nm
5.	120 yards	1093.6 yards	1.62 g	1000 g	67.73 Nm

Table calculation:

We know,
Yarn count = (Sample length×Unit weight)/(Unit length×Sample weight)

For observation 1,
N = (L×w)/(l×W) = (120×1000)/(1093.6×1.61) = 68.15 Nm

For observation 2,
N = (L×w)/(l×W) = (120×1000)/(1093.6×1.64) = 68.81 Nm

For observation 3,
N = (L×w)/(l×W) = (120×1000)/(1093.6×1.63) = 67.31 Nm

For observation 4,
N = (L×w)/(l×W) = (120×1000)/(1093.6×1.65) = 66.50 Nm

For observation 5,
N = (L×w)/(l×W) = (120×1000)/(1093.6×1.62) = 67.73 Nm

Average count = 67.32 Nm

Result:

The average yarn count is 67.32 Nm.