Determination of fiber fineness of cotton yarn by Sheffield micronaire instrument.

Experiment No: 06

Experiment Name: Determination of fiber fineness of cotton yarn by Sheffield micronaire instrument.

Introduction:

Fiber fineness determines how many fibers are present in the cross-section of a yarn of a given thickness. Minimum 30 fibers are needed in the yarn cross section but there are usually hundred. Fiber fineness is expressed in micronaire value.

Objectives:

(1) To determine regular and irregular fiber to making fine or coarse yarn.

(2) To make uniform yarn.

(3) To make good appearance fiber fineness is measured.

Machine description:

Sheffield micronaire is an instrument based on air flow principle. Air from a compressor is supplied to this instrument. The fest pedal is present to allow the air flow. The pressure of air is noted from the pressure gauge. An air filter is incorporated incline to filter the dust particles. The air is divided into the stream at the point x. One stream passes through the flow meter. The other passes through the perforations through the fibers in fiber camber and through the hole of the plunger to the atmosphere.

Working principle:

The rate of air flow is inversely proportional to the surface area of the fibers. A sample of known weight is compressed in a cylinder and subjected to an air current at a known pressure. The rate of an air flow through this process plug of fibers, related to the fineness of cotton fiber is measured.

Working procedure:

(1) At first we take 3.24 grams sample.

(2) The sample is opened very well to remove the dust.

(3) Then the sample is introduced into the compression chamber.

(4) The fiber compression plunger is inserted and locked in its place twisting the compresses the                sample into a process plug of fiber.

(5) The foot pedal is operated to allow air inside and reading is taken.

(6) Then foot pedal is operated to shut off the air flow. Then the sample is removed from the                       compression chamber.

(7) After that we get the micronaire value of that fiber. Take at least five value.

(8) Calculate average value and rating the fiber.

Calculation:

For observation 1,

Micronaire value = 3.5

For observation 2,

Micronaire value = 3.4

For observation 3,

Micronaire value = 3.5

For observation 4,

Micronaire value = 3.5

For observation 5,

Micronaire value = 3.4

Average micronaire value is 3.46

Table:

Observation no.	Micronaire value	Average value	Fiber rating
1.	3.5
2.	3.4
3.	3.5	3.46	Fine
4.	3.5
5.	3.4

Result:

From this average value we can say that this fiber is fine.

Determination of lb/spindle of jute yarn by wrap reel and electric balance.

Experiment No: 05

Experiment Name: Determination of lb/spindle of jute yarn by wrap reel and electric balance.

Introduction:

Yarn count is a numerical expression of fineness or coarseness and indicates the relationship between lengths to weight of the yarn. We can calculate the count in two systems:

(1) Direct system.

(2) Indirect system.

Pound/spindle is defined as the number of weight of 1 lb of 14400 yards. This is used for jute yarn.

Objectives:

(1) To know the count of jute yarn.

(2) Control the quality of yarn for better production.

(3) To maintain the requirement.

(4) To calculate yarn consumption.

(5) To calculate yarn fineness.

(6) To minimize the fault if found.

Machine description:

This machine contains more bobbins one tension and yarn taker. The wrap reel is used to measure the length of yarn. This yarn is taken by a wheel which circumference is 1.5 yards. Electrical balance is used to determine the weight of cotton yarn and we also use one bobbin carrier.

Working principle:

We know that lb/spindle count is a direct system count. The weight per unit length is the yarn count. The main feature of direct count system is that the length of yarn is fixed and the weight of yarn varies according to their fineness. The wrap reel used to contains the yarn and the electrical balance used to measure the weight of sample yarn.

Working procedure:

(1) At first we take a bobbin and put on a carrier.

(2) The yarn pass through the tensioner to the wrap reel.

(3) Then take a lee of yarn and measured weight by the electrical balance.

(4) Then complete the calculation to find out the count.

(5) Finally make a table according to calculation.

(6) Note the average count of yarn.

Calculation:

We know the jute yarn count

= (Sample weight(W)× Unit length(l))/(Unit weight(w)× Sample length(L))

For observation 1,

Count = (9.4×14400)/(453.5×30) = 9.95

For observation 2,

Count = (10.1×14400)/(453.5×30) = 10.70

For observation 3,

Count = (9.9×14400)/(453.5×30) = 10.47

For observation 4,

Count = (9.8×14400)/(453.5×30) = 10.37

For observation 5,

Count = (9.3×14400)/(453.5×30) = 9.84

Average count = 10.26

Table for count:

Observation no.	Sample length (yards)	Sample weight (gm)	Unit length (yards)	Unit weight (gm)	count	Average count
1.	30 yards	9.4 g	14400	453.5 g	9.95
2.	30 yards	10.1 g	14400	453.5 g	10.70
3.	30 yards	9.9 g	14400	453.5 g	10.47	10.26
4.	30 yards	9.8 g	14400	453.5 g	10.37
5.	30 yards	9.3 g	14400	453.5 g	9.84

 Result:       

The average jute yarn count is 10.26

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.

Determination of English Count of cotton yarn by wrap reel and electric balance.

Experiment No: 02

Experiment Name: Determination of English 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 in length per unit mass or mass per unit length.

Two types of count: 

(a) Indirect system. (English count, Metric count, Worsted count)
(b) Direct system. (Tex, Denier, Pound/Spindle)

English count:
It is the number of hanks of 840 yards for 1 pound of yarn.
Yarn count is denoted by ‘N’.
Mathematically,
N = (L×w)/(l×W)
Here,
N = Yarn count.
L = Sample length.
l = Unit length.
W = Sample weight.
W = Unit weight.

Unit length = 840 yds. (For English count)
Unit weight = 1 lb = 463.6 gm. (For English count)

Objectives:

(1) To know about the yarn count.
(2) To know about the wrap reel machine.
(3) To calculate the yarn fineness.
(4) To calculate the yarn smoothness.
(5) To know about English count.

Machine description:

In this experiment we use a wrap reel machine and an electric balance. The wrap reel machine is used measure the length of yarn. In this machine there is bobbin carrier where bobbin is kept and the yarn is taken from the bobbin and passed through guide to the wrap reel wheel where circumference is 1.5 yards. After measuring the length the electric balance is used to determine the weight of the yarn.
Working principle:
At first we will take a yarn package and put it to the bobbin carrier. Then we will pass the yarn through yarn tensioner and guide to wrap reel. Then we will rotate the machine wheel for 80 times to get the designed length. Then we will take the weight of the yarn. Then we will complete the calculation and find the yarn count.

Table:

Observation no.	Sample length	Unit length	Sample weight	Unit weight	Yarn count	Average count
1.	120 yards	840 yards	2.55 g	453.6 g	25.42 s
2.	120 yards	840 yards	2.54 g	453.6 g	25.51 s
3.	120 yards	840 yards	2.53 g	453.6 g	23.61 s	25.41 s
4.	120 yards	840 yards	2.52 g	453.6 g	23.31 s
5.	120 yards	840 yards	2.51 g	453.6 g	23.32 s

Table calculation:

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

For observation 1,
N = (L×w)/(l×W) = (120×453.6)/(840×2.55) = 25.42 s

For observation 2,
N = (L×w)/(l×W) = (120×453.6)/(840×2.54) = 25.51 s

For observation 3,
N = (L×w)/(l×W) = (120×453.6)/(840×2.53) = 25.61 s

For observation 4,
N = (L×w)/(l×W) = (120×453.6)/(840×2.52) = 25.31 s

For observation 5,
N = (L×w)/(l×W) = (120×453.6)/(840×2.51) = 25.32 s

Average count = 25.41 s

Result:

The average yarn count is 25.41 s.