DUET Journal
Vol. 1, Issue 3, June 2012
Effect of Machine Parameters on Knit Fabric Specifications
Shekh Md Mamun Kabir1 and Mohammad Zakaria2
1
Lecturer, Dept. of Wet Processing Engineering, Bangladesh University of Textiles, Tejgaon, Dhaka-1208, Bangladesh
2
Lecturer, Dept of Textile Engineering, Dhaka University of Engineering & Technology, Gazipur, Bangladesh
E-mail: [email protected]
ABSTRACT
Cotton knit fabrics of yarn count 16Ne, 20Ne, 26Ne, 30Ne, 40Ne and 120-200 GSM for plain, 165-280 GSM for rib,
205-250 GSM for interlock were investigated with different machine parameters. The investigation developed a way
so that it can be visualized or can forecast the resulting fabric specification with required configuration. The research
emphasized on the adjustable points on which fabric GSM, stitch length, fabric width, and compactness directly or
indirectly depends. It can be approached that the yarn count increases with the machine gauge. At different ranges of
GSM the variation of the finished fabric diameter with the machine diameter is different. From a constant, VDQ
number can be obtained for a particular stitch length and fabric design.
Key Words: GSM, Stitch length, Yarn count, Fabric Width, Machine gauge, Needle.
1. INTRODUCTION
Fabric or cloth is a flexible artificial material that is made
by a network of natural or artificial fibers. The example is
thread or yarn which is formed by weaving or knitting or
felting. So, fabric is a manufactured assembly of fibers
and/or yarns that has substantial surface area in relation to
its thickness and sufficient cohesion to give the assembly
useful mechanical strength. There are three principal
methods of mechanically manipulating yarn into textile
fabrics-interlacing, intertwining and interloping. All three
methods have evolved from hand manipulated techniques
through their application or primitive frames into
sophisticated manufacturing operations on automatic
machinery. Knitted fabric specification which are related to
knitted fabric production. In case of knitted fabric
specification GSM, stitch length is mainly considered. The
common problem of all industries is to produce knitted
fabrics of required GSM. Other specification like fabric
width, thickness is generally maintained in industries by
previous data sheet. So, problem occurs when an order
comes which never produced in previous. The goal of our
project is to find out easy process or method to take
decision about the selection of yarn count, loop length,
machine gauge and diameter for producing single jersey, rib
and interlock fabric of ordered GSM.
Many research works were carried out on the behavior of
fabric with machines specifications both experimentally &
numerically all over the world from different angle of
views. Iyer I., Mammel B., Schach J. [4], Ghazi Saeidi R.,
Latifi M., Shaikhzadeh Najar S., and Ghazi Saeidi A. [5],
Shady E., Gowayed Y., Abouiiana M., Youssef S. and
Pastore C [6] are some of the researchers who worked on
according to the “Circular knitting: technology process
Dhaka University of Engineering & Technology, Gazipur
structure yarn quality”, "Computer Vision-Aided Fabric
Inspection System for On-Circular Knitting Machine",
“Detection and Classification of Defects in Knitted Fabric
Structures”. Although a variety of research work carried out
from different perspective but the investigation of fabric
specification with the change of machine parameters is
relatively limited.
2. GENERAL DISCUSSION
2.1. Plain Structure
Plain is the base structure of ladies‟ hosiery, fully fashioned
knitwear and single-jersey fabrics. Its use in ladies‟ suiting
is known as the „Jersey Lily‟ (see in Fig.1). Other names
for plain include stockinet, whilst in the USA the term
„shaker stitch‟ is applied to it when knitted in a coarse
gauge of about 31– 32 needles Per inch (25mm).
2.2. Rib Structure
The simplest rib fabric is 1 X 1 rib. The ﬁrst rib frame was
invented by Jedediah Strutt of Derby in 1755, which used a
second set of needles to pick up and knit the sinker loops of
the ﬁrst set. It is now normally knitted with two sets of latch
needles. 1 X 1 rib is production of by two sets of needles
being alternately set or gated between each other. Relaxed 1
X 1 rib is theoretically twice the thickness and half the
width of an equivalent plain fabric, but it has twice as much
width-wise recoverable stretch. In practice, 1 X 1 rib
normally relaxes by approximately 30 percent compared
with its knitting width (see Fig. 2).
2.3. Interlock Structure
Figure 3 shows that interlock was knitted almost solely in
cotton on 20 gauge (needles per inch) machines for
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DUET Journal
Vol. 1, Issue 3, June 2012
underwear, a typical weight being 5oz per square yard (170
g per Square meter) using 1/40‟s s cotton, but from the
1950s onwards, 18 gauge machines were developed for
knitting double-jersey for semi-tailored suiting because the
open-width fabric could be finished on existing equipment.
As the machines became more versatile in their capabilities,
the range of structures became greater.
2.4. Circular Knitting Machine
Most single-jersey fabric is produced on circular machines
whose latch needle cylinder and sinker ring revolve through
the stationary knitting cam systems that, together with their
yarn feeders, are situated at regular intervals around the
circumference of the cylinder. The yarns is supplied from
cones, placed either on an integral overhead bobbin stand or
on a free-standing creel, through tensioners, stop motions
and guide eyes down to the yarn feeder guides (see Fig. 4).
Fig. 4: Circular knitting machine
Fig. 1: Structure of single jersey knitted fabric.
Machine Parts:
1. Yarn feeder guide, 2. Latch needle, 3. Holding-down
sinker, 4. Needle cylinder, 5. Cylinder driving wheel.
6. Cylinder driving gear, 7. Sinker-operating cams, 8.
Sinker cam-cap, 9. Sinker trick ring, 10. Needle-retaining
spring, 11. Needle-operating cams, 12. Cam-box, 13. Camplate, 14. Head plate, 15. Cylinder driving pinion attached
to the main drive shaft.
3. MACHINE PARAMETERS
Fig. 2: Structure of 1X1 Rib fabric.
Dial loops
1.
2.
3.
4.
Machine gauge.
Machine Diameter.
V.D.Q Pulley
Needle gauge.
3.1. Machine Gauge
No. of needles per inch present in a needle bed of a knitting
machine is called machine gauge for that knitting machine.
Selection of machine gauge depends upon the following:
Yarn count, Fibre type, Yarn twist, Yarn finished. General
practices of machine gauge and yarn count in different
industries in Bangladesh are shown in Tables- 1, 2 & 3.
From this study of the data collected from the different
factories we can see that the gauge increases with the
English count (Ne) of the yarn.
Course
Cylinder loops
Fig. 3: Structure of interlock fabric
Dhaka University of Engineering & Technology, Gazipur
3.2. Machine Diameter
Machine diameter is mainly diameter of m/c cylinder. It is
important for fabric width. Only diameter does not fetermi-
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DUET Journal
Vol. 1, Issue 3, June 2012
Table 1: Typical Selection of M/C Gauge for Different
Count Yarn:
Count (Ne)
Gauge
Low
High
Limit
32
32/1
46/1
60/1
28
30/1
46/1
60/1
24
20/1
46/1
50/1
22
20/1
40/1
20
20/1
40/1
18
20/1
40/1
16
10/1
24/1
Table 2: Relation between machine gauge and yarn count
(Single jersey):
Count
(Ne)
30
26
20
30
34
28
30
30
30
30
34
18
20
22
24
24
24
24
24
24
24
24
M/C
gauge
24
24
24
24
24
24
24
24
24
28
28
Count
(Ne)
30
30
40
28
28
30
34
34
26
40
50
Table 3: Relation between machine gauge and yarn count
(1X1 Rib & Interlock)
1X1 Rib
M/C
gauge
18
16
16
18
18
18
16
Count (Ne)
30
28
30
26
24
28
30
V.D.Q a Stitch length (when needle is same)
V.D.Q a No. of Needle (when stitch is same)
 From the above two expression we get,
V.D.Q a Stitch length X Needle
Constant, Kv =
This constant Kv varies with the diameter of the machine,
type of the machine (single or double jersey), different
brand of machines. [Shown in Table-7]
Table 4: Relationship between M/C diameter and fabric
diameter (single jersey)
S/J
M/C gauge
with the yarn wheel. By varying the dia of the V.D.Q
pulley, which is at the driver position, the amount of the
yarn feeding can be controlled. This variation in the yarn
feeding varies the stitch length and the G.S.M (see Fig.8).
Interlock
M/C
Count (Ne)
gauge
24
46
24
46
24
40
24
40
24
34
24
36
24
36
ne the fabric width. It also needs machine gauge and wales
space which is depends upon yarn count and loop length
(see Tables- 4, 5, 6 & Fig.5, 6, 7). Tables show that same
machine with the specific diameter can produce fabrics
with different width.
3.3. V.D.Q (variable dia. for quality) Pulley
V.D.Q pulley is a pulley which drives several smaller
pulleys by a tooted belt. These smaller pulleys are at the
driven position and drive a clutch device which engages
Dhaka University of Engineering & Technology, Gazipur
M/C
M/C
Dia.
(inch)
20
20
24
28
30
36
38
40
42
Finished dia. of fabric (inch)
M/C
Gauge
24
20
24
24
24
24
24
24
24
Count20/1
Ne &
Fin
GSM190200
23.2
19.6
27.4
32.6
35
42
44.5
46.7
48.9
Count
-24/1
Ne &
Fin
GSM175185
21.7
18.4
25.7
30.8
32.8
39.6
41.7
43.8
45.8
Count
-26/1
Ne &
Fin
GSM155165
20.8
18
24.6
29.3
31.5
38
40
42
44
Count
-40/1
Ne &
Fin
GSM110120
16.1
18
19.1
22.7
24.4
29.4
31
32.5
34.1
Fig. 5: Change of fabric diameter with machine diameter
with respect to GSM.
3.4. Needle Gauge
Thickness of needle express by the needle gauge. It is
important for selection of machine gauge. Needle gauge is
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DUET Journal
Vol. 1, Issue 3, June 2012
differing for the different needle types and different Brand
(see Fig. 9). According to the result of study Machine
gauge is 24 then Needle thickness is 0.52mm and Machine
gauge is 28 then Needle thickness is 0.41mm.
Table 6: Relationship between M/C diameter and fabric
width (Interlock).
Interlock
M/C
M/C
Dia.
(inch)
30
36
38
Finished dia. of fabric (inch)
M/C
Gauge
Count30/1 Ne &
Fin GSM250-260
Count34/1 Ne
& Fin
GSM225-240
Count40/1 Ne
& Fin
GSM205-215
22
22
22
26
31
33
26.5
34
36
29
35
37
Fig. 6: Change the fabric diameter with M/C diameter with
respect to GSM
Fig. 8: V.D.Q pulley.
4. RESULTS AND DISCUSSION
Fig. 7: Change the fabric diameter with M/C diameter with
respect to GSM
Table 5: Relationship between M/C diameter and fabric
width (1X1 Rib)
M/C
M/C
Dia.
(inch)
30
36
40
42
M/C
Gauge
18
18
18
18
1X1 Rib
Finished dia. of fabric (inch)
Count- Count- Count- Count20/1
24/1
26/1
40/1
Ne &
Ne &
Ne &
Ne &
Fin
Fin
Fin
Fin
GSM- GSM- GSM- GSM270230215155280
240
225
165
34
32
31
26
40
38.5
37
32
44
43
41.5
36
46
45
43.5
38
Dhaka University of Engineering & Technology, Gazipur
We have got some result from different experiment of
various fabric parameters. From the research we have found
some relation among the fabric Specifications with the
machine parameters. The result is based on the data
collected from the factories.
4.1. Selection of the gauge corresponding to the yarn
count
In the industry there is a range of yarn counts that a
particular gauge of a machine can accommodate. They
follow the range to select the precise gauge. Now we have
analyzed the data to see the variations of yarn count with
machine gauge. The table is as follow: [Table-8] Usually
the yarn count increases with the machine gauge.
4.2. Relation between M/C dia and fabric dia
The fabric dia is the width of the fabric in the tubular form.
The finished fabric dia varies with the M/C dia. At different
ranges of GSM the variation of the finished fabric dia with
the M/C dia is different. Different fabric structures show
different variation. But same structure follows a particular
path of variation.
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DUET Journal
Vol. 1, Issue 3, June 2012
4.3. V.D.Q pulley constant
There is a relation of V.D.Q number, stitch length and
needle number. It is,
Constant, Kv =
This constant is dependent mainly on the M/C. Different
machine type, brand; diameter can vary the value of the
constant. For a given machine the constant is same.
For Single jersey fabric the V.D.Q pulley constant is
41.20825 & for Rib fabric the V.D.Q pulley constant is
68.76084.
With these values a better selection of VDQ number can be
obtained for a particular stitch length.
Fig-9: Needle in knitting machine.
Table 7: The value of Kv for different M/Cs
M/C
S/J
Rib
Dia. X Gauge
1
2
3
1
2
3
23*24
23*24
24*24
38*24
38*24
34*24
No. of
Needle
1728
1728
1800
2136X2
2136X2
1920X2
V.D.Q
125
110
118
151
100
102
Stitch Length
(mm)
2.90
2.60
2.75
2.55
1.70
2.55
Table 8: Relation of Machine gauge with yarn count
Gauge
32
28
24
22
20
18
16
Count (Ne)
Low
32/1
30/1
20/1
20/1
20/1
20/1
10/1
High
46/1
46/1
46/1
40/1
40/1
40/1
24/1
Limit
60/1
60/1
50/1
5. CONCLUSIONS
In this research we tried to analyze and observe different
characteristics of the fabric specifications and machine
parameters and to build up some relations among those.
Most of the relations are building with the help of the data
collected from the mills and factories. Some of the data are
collected gained by experiments.
In some cases our data was limited. The limitation of data
may create some undesirable consequences. More data have
to be collected to obtain a precise result. Experiments have
to be done on the common fabrics and other fabrics to get a
better understanding of the fabric specifications and
machine parameters.
Dhaka University of Engineering & Technology, Gazipur
Constant, Kv =
40.0896
40.8436
41.9499
72.1430
72.624
78.336
REFERENCES
[1] David J. Spencer, Knitting Technology by “Wood head
Publishing Limited”- Third Edition.
[2] Horrocks & Anand, Handbook of Technical Textile
[3] Professor J E Mclintyre & P N Daniels, Textile Terms
& Definitions published by “The Textile Instute”Tenth Edition.
[4] Iyer I., Mammel B., Schach J., Circular knitting:
technology process structure yarn quality, Second
Edition, Meisenbach GmbH, Bambreg, Germany,
1957.
[5] Ghazi Saeidi R., Latifi M., Shaikhzadeh Najar S., and
Ghazi Saeidi A., "Computer Vision-Aided Fabric
Inspection System for On-Circular Knitting Machine"
Textile Research Journal, 75(6), 492497, 2005.
[6] Shady E., Gowayed Y., Abouiiana M., Youssef S. and
Pastore C., Detection and Classification of Defects in
Knitted Fabric Structures, Textile Research Journal,
76(4),295-300, 2006.
[7] Abouiiana M., Youssef S., Pastore C. and Gowayed Y.,
Assessing structure changes in knits during processing,
Textile Research Journal, 73(6), 535-540, 2003.
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