presentation

2. BANGLADESH UNIVERSITY OF TEXTILES
TEJGAON, DHAKA-1208
B.Sc. IN TEXTILE ENGINEERING, EXAM-2012
Project on
Effects of Different Parameters on Spirality of Single Jersey Knitted Fabric
SUPERVISING TEACHER
Md. Emdad Sarker
Lecturer,
Department of Fabric
Manufacturing Engineering,
Bangladesh University of Textiles.
Prepared By-
Rakib Ahmed. ID-20091050
Tanvir Ahmed. ID-20091085
Md. Nashirul Islam. ID-20091086
Sabbirul Islam. ID-20091100

3. Spirality is a dimensional distortion in circular
plain knitted fabrics. The lengthwise rows of
stitches, called wales or needle lines, should
occupy a truly vertical line in the fabric and should
always be at right angles to the cross wise courses
of stitches. Many times the wales may skew to the
right or left forming an angle, which appears in
the form of a twilled surface. This geometrical
defect has been termed spirality of knitting in
circular fabrics
What is spirality?

4. Literature survey:
A research was done by M.D De ARAUJO, (Centro de Tecnologia Textil,
Universidade do Minho, Guimaraes 4800, Portugal)& G.W. Smith (College of
Textiles, North Carolina State University, Raleigh, North Carolina 27695,
U.S.A.) on the Effect of yarn spinning technology on spirality. They had
concluded that 50/50 blend yarns produce less spirality than 100% cotton
yarns.
Another research on the effect of yarn and fabric construction on spirality of
cotton single jersey fabric was done by JIANGTAO, R.C DHINGKA, E.K.
CHAN and M.S ABBAS in Institute of Textiles & Clothing, The Hong Kong
Polytechnic University.
Here, researchers derived some important equations representing spirality
like,
Spirality = 13.5 + 0.95 TF – 1.89 K,
Spirality= 9.8 + .82 TF – 2.84 K + 18.51 S
Here, the units of spirality, twist factor ( TF) and tightness factor (K) are
degree, √ tex X tpc and √ tex X cm-1, respectively.

5. Apparatus & machine Used:
GSM Cutter Wrap Reel

6. HATRA course
length tester
Yarn tension
meter

7. Machine Brand: Orizio
Origin: Italy
Machine Model: CMO 4A
Dia x Gauge: 32x28
Number of feeder: 96
Number of needle: 2820
Machine Brand: Wellknit
Origin: Taiwan
Machine Model: WS/3.0 F-B (BD)
Dia x Gauge: 30x28
Number of feeder: 90
Number of needle: 2640

8. Methodology:
We chose Epyllion fabric ltd and Padma poly cotton ltd for doing the job which
is related to our project.
We tried to find out the deviation of spirality with the deviation of different
machine related parameters such as machine speed, diameter, gauge and no. of
feeder. For this purpose we select knitting floor of Padma poly cotton. At first
we made grey knitted fabric by running the machine at different rpm using
same yarn and keeping the number of feeders and diameter, gauge fixed and
rpm of machine was recorded. Then we produced different knitted fabric by
varying the tension of feeding yarn. We recorded the yarn tension was given and
indicated the fabrics separately. These fabrics were scoured, bleached and finished
at Padma poly cotton. After relaxing, spirality was measured.

9. As spirality does not depend only machine parameters we had to find out
spirality variation according to different fabric related parameters so, for this
purpose we chose Epyllion fabric ltd to do the job. There we produced
several fabric samples with different stitch length when other parameters
were fixed. We made the same fabric with yarn of different count when
GSM and stitch length was within a range. Like the same process we were
able to produce knit fabric by changing GSM but keeping stitch length and
yarn count fixed.
These fabrics were scoured, bleached, dyed and finished separately with
running bulk production of factory order. After drying the fabric we
measured the spirality of different fabric and recorded. In some cases fabrics
were dried by tumble dryer as requirement of buyer.
Then we analysis these data and tried to find out the relation between
spirality and other parameters.

11. Measuring the spirality:
Spirality was measured in percentage. This measuring way was practiced in the industries of
Bangladesh. Fabric was cut from the roll at the measurement of (35cm´35cm). Three sides
are stitched. Then the stitched fabric pieces were washed with detergent for an hour and
then those were dried in tumble dryer. After conditioning half an hour in the lab
temperature, the spirality of the fabrics were measured. For measuring the spirality, at first
the displacement of the wales was measured, then the length of the wales was taken from
the displaced point to the top of the fabric piece.

12. Experimental
Data

13. Exp. No. Yarn count No. of feeder Stitch length
(mm)
Spirality angle
1 28 90 2.74 0.00%
2 28 90 2.75 1.00%
3 28 90 2.75 4.3%
4 28 90 2.78 4.5%
5 28 90 2.80 7.5%
Relation between spirality and stitch length:
0.00%
1.00%
4.30% 4.50%
7.50%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
2.74 2.75 2.75 2.78 2.8
Spirality%
Spirality angle
Spirality angle
Remarks:
Spirality gradually increases with the
stitch length as increasing stitch
length loosen the fabric structure and
knitted loops tend to deform more
after relaxation.

14. Relation between spirality and yarn count:
Exp. No. Dia x gauge Stitch length Yarn count(mm) Spirality angle
1 30x24 2.76 24 1.00%
2 30x24 2.75 26 2.29%
3 30x24 2.75 28 4.3%
4 30x24 2.75 30 5.14%
5 30x24 2.8 30 7.50%
1.00%
2.29%
4.30%
5.14%
7.50%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
24 26 28 30 30
Spirality
Spirality angle
Spirality angle
Remarks:
Spirality increases with yarn
count as we know TPI increases
with yarn counts and yarn tends
to twist back more after
relaxation of fabric.
Limitation:
Stitch length should be constant
in this experiment which we
couldn’t as stitch length is
changed due to changing of yarn
count.

15. Relation between Spirality and yarn count & stitch length:
From previous literature we have come to know, Spirality ∝ yarn count and Spirality ∝ stitch length so it is
very obvious that spirality ∝ (yarn count × stitch length)
Exp. No. Dia x
Gauge
Yarn
count(Ne)
Stitch length
(mm)
Yarn count x
Stitch length
Spirality
angle
1 30x24 24 2.76 66.24 1.00%
2 30x24 26 2.75 71.5 2.29%
3 30x24 28 2.75 77 4.3%
4 30x24 30 2.75 82.5 5.14%
5 30x24 30 2.8 84 7.50%
1.00%
2.29%
4.30%
5.14%
7.50%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
66.24 71.5 77 82.5 84
Spirality
Spirality angle
Spirality angle
Discussion:
In previous experiment we found
S.L changes with yarn count so
we tried to find out a relation
between these parameters &
spirality.
Remarks:
Spirality increases with the
increasing of count x S.L as it
loosen the fabric.

16. 4.Relation between spirality and GSM:
Exp.
No.
Dia x
gauge
Yarn count
(Ne)
Stitch length
(mm)
GSM
(finished)
Spirality
angle %
1 30x24 28 2.78 160 4.50%
2 30x24 28 2.80 161 2.00%
3 30x24 28 2.80 163 1.00%
4 30x24 28 2.75 167 1.00%
5 30x24 28 2.80 168 1.00%
6 30x24 28 2.80 170 2.00%
0.00%
0.50%
1.00%
1.50%
2.00%
2.50%
3.00%
3.50%
4.00%
4.50%
5.00%
160 161 163 167 168 170
Spirality%
GSM
Spirality
Spirality angle %
Spirality angle %
Remarks:
Spirality decreases with the
increasing of GSM of knitted fabric
up to a certain limit then it could be
increased when stitch length is kept
within a range. The reason is higher
GSM means higher compactness of
the fabric, and higher compactness
allows less space for untwisting the
yarn resulting less spirality.
Limitation:
In this experiment we should keep
S.L and yarn count constant which
we could not as these are
interrelated.

17. Relation between spirality and GSM, yarn count and stitch length:
From previous literature we have come to know, Spirality ∝ yarn count; Spirality ∝ stitch length and Spirality ∝
.
So, it should be Spirality ∝
Exp. No. GSM Yarn count S.L NexSL/GSM Spirality
1 182 24 2.7 0.356044 1.00%
2 162 26 2.75 0.441358 1.43%
3 157 26 2.75 0.455414 2.29%
4 152 28 2.75 0.506579 4.30%
5 150 30 2.8 0.56 7.50%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
0.356044 0.441358 0.455414 0.506579 0.56
Spirality%
NexSL/GSM
Spirality
Spirality
spirality
Discussion:
As we have seen from previous experiment one
parameter can’t be changed by keeping other
fixed so we tried to find out a relation between
spirality and these parameters by changing all
of them.
Remarks:
Spirality increases with the increasing of the
value of (NexSL/GSM).

18. From the formula of GSM we know that, GSM=
So if WPI, CPI remains constant then Spirality ∝
Exp. No. GSM Yarn count
(Ne)
Stitch
length
(GSM x Yarn
count)/ Stitch
length
Spirality%
(mm)
1 125 32 2.7 1481.48 4.50%
2 157 26 2.75 1484.36 2.29%
3 180 24 2.88 1500.00 0.00%
4 162 26 2.75 1531.64 1.43%
5 152 28 2.75 1547.64 4.30%
6 182 24 2.76 1582.61 1.00%
7 150 30 2.8 1607.14 7.50%
8 160 28 2.78 1611.51 4.50%
9 188 24 2.76 1634.78 2.00%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
1481.48 1484.36 1500.00 1531.64 1547.64 1582.61 1607.14 1611.51 1634.78
Spirality%
(GSM × Count) ÷ SL
Spirality
Spirality%
Spirality
Remarks:
No significant result was not
found.

19. Relation between Spirality and Tightness factor:
As tightness factor indicates the looseness or tightness of a fabric. So spirality should be dependent on
tightness factor and we know, Tightness factor =
Exp. No. Yarn count
(Ne)
Yarn count
(Tex)
Stitch
length (mm)
Tightness
factor
Spirality %
1 20 29.52 3.80 14.3 1.00%
2 30 19.7 2.95 15.05 5.50%
3 36 16.4 2.67 15.17 3.00%
4 28 21.1 2.85 16.12 2.00%
5 28 21.1 2.80 16.4 1.00%
6 28 21.1 2.75 16.7 1.00%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
14.3 15.05 15.17 16.12 16.4 16.7
Spirality%
Tightness factor
Spirality
Spirality %
spirality
Remarks:
We can see from the frequency polygon
that spirality decreases with increasing of
Tightness factor as increasing tightness
factor allows lees space for yarn to twist
back to cause spirality.

20. Exp. No. GSM Yarn
count
(Ne)
Yarn count
(Tex)
Stitch
length
(mm)
Tightness
factor, ‘X’
(GSM x
Yarn
count)/
Stitch
length, ‘Y’
(GSM x
count)/ (SL x
Tightness
factor);
‘Y/X’
Spirality%
1 157 26 22.71 2.75 17.33 1484.36 85.65 2.29%
2 180 24 24.60 2.88 17.22 1500.00 87.09 0.00%
3 182 24 24.60 2.76 17.97 1582.61 88.06 1.00%
4 162 26 22.71 2.75 17.33 1531.64 88.38 1.43%
5 188 24 24.60 2.76 17.97 1634.78 90.96 2.00%
6 152 28 21.09 2.75 16.70 1547.64 92.68 4.30%
7 125 32 18.45 2.7 15.91 1481.48 93.12 4.50%
8 160 28 21.09 2.78 16.52 1611.51 97.55 4.50%
9 150 30 19.68 2.8 15.84 1607.14 101.43 7.50%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
7.00%
8.00%
85.65 87.09 88.06 88.38 90.96 92.68 93.12 97.55 101.43
Spirality%
(GSM x Yarn count)/(Stitch length x tightness factor)
Spirality
Spirality%
Spirality
Remarks:
Spirality doesn’t depend on (GSM x Yarn
count)/ Stitch length.But we have found a
relation among GSM, stitch length, yarn
count and tightness factor. A proportional
relation is found between spirality and
(GSM x Yarn count)/(Stitch length x
tightness factor).
Relation between Spirality and GSM, Count, Stitch length, Tightness factor:

21. Exp.
No.
GSM Yarn
count
(Ne)
Yarn
count
(Tex)
Stitch
length
(mm)
Tightness
factor,X
(GSM x
Yarn
count)/
Stitch
length, Y
(GSM x
count)/ (SL
x Tightness
factor);
Y/X
Spirality%
1 163 28 21.09 2.8 16.40 1630.00 99.38 1.00%
2 167 28 21.09 2.75 16.70 1700.36 101.82 1.00%
3 168 28 21.09 2.8 16.40 1680.00 102.43 1.00%
4 170 28 21.09 2.85 16.11 1670.18 103.65 2.00%
5 128 36 16.40 2.67 15.17 1725.84 113.78 3.00%
0.00%
0.50%
1.00%
1.50%
2.00%
2.50%
3.00%
3.50%
99.38 101.82 102.43 103.65 113.78
Spirality%
(GSM x count)/ (SL x Tightness factor)
Spirality
Spirality%
Spirality
Relation between Spirality and GSM, Count, Stitch length, Tightness factor (after
tumbling):
Remarks:
Spirality doesn’t depend on (GSM x Yarn
count)/ Stitch length but we have found a
relation among GSM, stitch length, yarn
count and tightness factor. A proportional
relation is found between spirality and
(GSM x Yarn count)/(Stitch length x
tightness factor) even after tumble
drying.

22. Relation between spirality and yarn tension:
Exp. No. Yarn tension
(cN)
Stitch length No. of feeder Spirality
angle%
1 6.5 2.73 96 3.33%
2 7.5 2.73 96 1.43%
3 8.0 2.73 96 1.44%
4 8.5 2.73 96 5.03%
5 9.0 2.73 96 2.85%
6 10.0 2.73 96 2.14%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
6.5 7.5 8 8.5 9 10
Spirality%
Yarn tension
Spirality
spirality
Spirality angle%

23. Relation between spirality and machine rpm:
Exp. No. Cylinder
rotation
direction
Yarn count
(Ne)
RPM Spirality%
1 Clockwise 30 20 3.33%
2 Clockwise 30 26 1.43%
3 Clockwise 30 30 1.44%
4 Clockwise 30 35 5.03%
5 Clockwise 30 40 2.85%
6 Clockwise 30 45 2.14%
0.00%
1.00%
2.00%
3.00%
4.00%
5.00%
6.00%
20 26 30 35 40 45
Spirality%
RPM
Spirality
Spirality%
Spirality

24. Result & Findings:
From the research we can infer-
•The loop length has an effect on spirality. For minimizing spirality, loop length or stitch
length should not be also high so that the yarns have more space to be untwisted.
•Spirality% increases with yarn count as we know TPI increases with yarn counts& yarn
tends to twist back more after relaxation of fabric.
•Spirality shows a relation with the product of stitch length and count (Stitch length x
Yarn count)
•Spirality decreases with the increasing of GSM of knitted fabric up to a certain limit
then it could be increased when stitch length is kept within a range.
•Tried to find a term (Stitch length x Yarn count)/ GSM& make relationship with
spirality, get proportional relation.
•Spirality decreases with increasing of tightness factor.
•Develop a term (GSM x Yarn count)/(Stitch length x tightness factor), & spirality
increases with the value of this term. And there would be no spirality if the value of
(GSM x Yarn count)/(Stitch length x tightness factor)is around 87.
•No significant effect of feeding yarn tension has been found on spirality
•Machine RPM does not show any significant effect on spirality.

25. Limitation:
•This project will be much more accurate if we produced fabric
considering different parameters on a single machine. But we couldn’t
manage a single machine in the factory that they were letting us to use on
our purpose. In that reason we rely on different machine of our
predetermined parameters. Result may be different in case of
experimenting fabric spirality produced on same machine.
•We couldn’t maintain same dyeing and finishing process & condition.
•We should use yarn of same lot. But we could not produce the fabrics
by the yarn of same lot.
•We tried to find the effect of one factor (stitch length or gsm or count)
on spirality while strictly maintaining the other factors constant. But in
some cases we couldn’t maintain that premises because they are closely
interrelated and in that cases we kept our factor data in a small range.