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COM-4
CONCEPT:
With the ComforSpin
technology a new yarn with perfect yarn structure
– the COM4 yarn - has been established in
the market. With the help of a microscope the structure
of the yarns can easily be compared: The conventional
ring yarn shows to be far less perfect than commonly
assumed. The long, protruding fibres cause a number
of problems in downstream processing. COM4
yarn shows a very compact structure with highly
parallel fibres and much less disturbing hairiness.
The air current created
by the vacuum generated in the perforated drum condenses
the fibres after the main draft. The fibres are
fully controlled all the way from the nipping line
after the drafting zone to the spinning triangle.
An additional
nip roller prevents the twist from being propagated
into the condensing zone. The compacting efficiency
in the condensing zone is enhanced by a specially
designed and patented air guide element.
Optimal interaction
of the compacting ele-ments ensures complete condensation
of all fibres. This results in the typical COM4
® yarn characteristics.
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The ComforSpin ® technology allows
aero-dynamic parallelization and condensation of the fibres
after the main draft. The spinning triangle is thus reduced
to a minimum. The heart of ComforSpin machine
is the compacting zone, consisting of the following elements:
• perforated drum
• suction insert
• air guide element
The directly driven perforated
drum is hard to wear and resistant to fibre clinging.
Inside each drum there is an exchangeable stationary suction
insert with a specially shaped slot. It is connected to the
machine’s suction system.
THE ELITE YARN:
The operating method of the SUESSEN
EliTe Spinning System is well-known.After the fibres leave
the drafting system they are condensed by an air-permeable
lattice apron,which slides over an inclined suction slot.The
fibres follow the outer edge of this suction slot and at the
same time they perform a lateral rolling motion.
Above
the front bottom roller of the drafting
system,the fibre band influenced
by high draft is spreading.In the area of the suction
slot,which is covered by the lattice apron,the fibre band is
condensed.Commencing from the semi-dotted clamping line of the
EliTe Q Top Roller,twist is being
inserted.There is no spinning triangle.
The improvement achieved is shown
in Fig .The left side displays the fibre triangle at
the exit of a conventional ring frame drafting system.The twist
imparted by the spindle cannot flow up to the clamping line.The
outer fibres spread out and are thus more highly tensioned than
those on the inside. The
right side of the picture does not show a spinning triangle.The
yarn twist flows right up to the clamping line.The yarn is round
and smooth.

Since the spinning triangle is
very very small, the end breaks will be very less and therefore
the fly liberation will also be less.
Condensing of the fibr bundle,which
follows the drafting process,can already be seen as a significant
development of the ring spinning technology.Condensed ring yarn
is more than a speciality.In view of its manifold advantages.
It is of technological importance
that the suction leve l relevant for the condensing operation
is exactly the same for all spinning positions. To fulfil this
criteria,individual motors combined with suction units for
6 spinning positions,have been arranged accordingly.This
provides short air-flow distances with identical negativ pressures
at all spinning points .
During yarn formation all fibres
are perfectly condensed and gathered parallel to each other
in the compacting zone. Consequently all fibres are twisted
in and contributing to the superior fibre utilisation rate compared
to conventional ring yarn. The result is exceptionally low hairiness
combined with higher yarn tenacity and elongation. These are
the unique characteristics of these yarns.
ADVANTAGES OF COMPACT YARN:
• higher fibre utilisation
• higher tenacity with same twist
factor, or
• same tenacity with reduced
twist factor for higher production
• lowest hairiness (highest reduction
in hairs longer than 3 mm)
• fewer weak points
• better imperfections (IPI)
values
• higher abrasion resistance
• greater brilliance of colour
• intensive dye penetration
• no singeing before printing
- Due to better utilization
of fibre substance it is possible to reduce yarn twist of
these Yarns,particularly of knitting yarns,by up to 20%,maintaining
the yarn strength of conventional ring yarns.This increases
yarn production. The ends-down rate in spinning these Yarns
is reduced by 30 to 60%,which improves machine efficiency.
- Applying the same winding
speed as with conventional ring yarns,there are less raised
points in these Yarns and the increase in yarn imperfections
is reduced because they have a better resistance to shifting.
Higher winding speeds are therefore possible with
compact yarns Yar ns .
- In accordance with up to
20%twist reduction in spinning compact yarns ,the twisting
turns can be reduced for certain types of yarn.As a result,production
of twisting frame is increased and twisting costs are reduced.
- Owing to the lower hairiness
and higher tenacity of compact Yarns,the ends-down rate
in beaming is reduced by up to 30%.Higher beamer efficiency,higher
produc tion and fewer personnel for repair of ends-down
in beaming are the consequence.
- Compact Warp yarns
help to save up to 50%of sizing agent,while the running
behaviour of weaving machi-nes is the same or even better.
Cost can be saved in sizing and desizing processes.
- Owing to the better work
capacity of compact Yarns ,ends down can decreased
by up to 50% in the warp and by up to 30%in the weft. Efficiency
is consequently increased by 2 to 3%, production is increased
and weaving costs are reduced. In practice,the average
ends-down rate is reduced by 33% per 100,000 weft insertions
of compact Yarns on rapier weaving machines
and by 45% on air-jet weaving machines. Instead of
a weft insertion of 500 –600 m/min with conventional ring
yarn,700-800 m/min is possible with compact Yarns
on air-jet weaving machines.
- Due to reduced Yarn hairiness,singeing
can sometimes be dispensed with,or it can be carried out
at a higher cloth advance speed.As a result,production costs
are considerably reduced.
- fibres upto 7% can be saved
because singing can be avoided
- Dyeing and Printing
Improved structure of compact Yarns and their reduced
twist favours the absorption of colour pigments and chemical
finishing agents.Saving of dyestuff is possible.
- Owing to the improved
yarn strength, compact Yarns are well suited for non-iron
treatment of woven fabrics. In the course of such treatment,the
strength of fabrics made from conventional ring yarns can
decrease by up to 25%,with frequent problems in the manufacture
of clothes. compcat Yarns make up for this loss in strength.
- Knitting
:Compact Yarns with their increased yarn strength and reduced
formation of fluff permit to achieve higher machine efficiency
and therefore production on knitting machines at a reduced
ends-down rate,less interruptions and less fabric faults.
Production costs therefore decrease. The enormously low
hairiness of compact Yarns often permits to dispense
with usual waxing. Considerable cost saving is achieved
because of this.
- In knitting
fibre abrasion reduced by 40%
due to low hairiness. Fewer defects/ yarn breaks and
better quality. Less contamination on all machines by foreign
fibres . Less wear of needles, guide elements and sinkers
due to less dust in the compact Yarn . Low hairiness has
positive impact on loop structure . L Low pilling
values get more and more important . In many cases single
compact Yarns substitute conventional ply yarns. Waxing
can be reduced or completely dispensed with .
- Compact Yarns are
much more suitable for warp knitting than conventional ring
yarns,because of their higher work capacity and lower
hairiness. They are predestined to bear the high load due
to numerous deflecting points with high friction in the
warp knitting machine.
- Due to better embedding
of fibres (including short ones)in compact Yarn,approx.6%fewer
combing noils are possible.
- Cheaper carded qualities
instead of combed qualities can be spun with the Compact
Spinning ystem.
- in many cases single EliTe
® Yarns can substitute conventional ply yarns
- new qualities can be developed,
opening up a new creative scope for products
-
Hairiness Testing of Yarns
Hairiness of yarns has been discussed
for many years,but it always remained a fuzzy subject. With
the advent of compact yarns and their low hairiness compared
to conventional yarns,the issue of measuring hairiness and the
proper interpretation of the values has become important again.Generally
speaking,long hairs are undesirable, while short hairs are desirable
(see picture ). The picture shown below just give
a visual impression of undesirable and desirable hairiness at
the edge of a cops.
Figure:

RING YARN
COMPACT YARN
There are two major manufacturers
of hairiness testing equipment on the market,and both have their
advantages and disadvantages. Some detail is given below.
USTER
USTER is the leading manufacturer
of textile testing equipment. The USTER hairiness H is defined
as follows .
H =total length (measured in
centimeters) of all the hairs within one centimeter of yarn
.
(The hairiness value given by
the tester at the end of the test is the average of all these
values measured, that is,if 400 m have been measured,it is the
average of 40,000 individual values) . The hairiness H is an
average value,giving no indication of the distribution of the
length of the hairs. Let us see an example
| |
0.1cm |
0.2cm |
0.3cm |
0.4cm |
0.5cm |
0.6cm |
0.7cm |
0.8cm |
0.9cm |
1.0cm |
total |
| yarn 1 |
100 |
50 |
30 |
10 |
5 |
6 |
0 |
2 |
1 |
0 |
398 |
| yarn 2 |
50 |
10 |
11 |
5 |
10 |
0 |
5 |
10 |
0 |
11 |
398 |
Both yarns would have the same
hairiness index H, even though yarn is more desirable,as
it has more short hairs
and less long hairs,compared to yarn 2.
This example shows that the hairiness
H suppresses information,as all averages do. Two yarns with
a similar value H might have vastly different distributions
of the length of the individual hairs.
The equipment allows to evaluate
the variation of the value H along the length of the yarn.
The "sh value "is given, but the correlation to the CV of hairiness
is somehow not obvious.A spectrogram may be obtained.
2.ZWEIGLE
Zweigle is a somewhat less well
known manufacturer of yarn testing equipment. Unlike USTER,the
Zweigle does not give averages. The number of hairs of different
lengths are counted separately, and these values are displayed
on the equipment. In addition, the S3 value is given,which is
defined as follows:
S3 =Sum (number of hairs 3 mm
and longer)
In the above example,the
yarns would have different S3 values:
S3yarn 1 =2 .
S3yarn 2 =4 .
A clear indication that yarn
2 is "more hairy "than yarn 1. The CV value of hairiness
is given a histogram (graphical representation of the distribution
of the hairiness) is given.
The USTER H value only gives
an average,which is of limited use when analyzing the hairiness
of the yarn.The Zweigle testing equipment gives the complete
distributionof the different lengths of the hairs.
The S3 value distinguishes between
long and short hairiness, which is more informative than the
H value.
Ten Fundamental Rules for Successful
Operation of EliTe Ring Spinning Machines:
1.EliTe Q Spinning Machines produce
yarn of supreme quality and come up to the expectations.
Installation of the machine in the spinning mill EliTe
Q Spinning Machines have a considerable air flow rate –a machine
with .1008 spindles sucks in about 60 cubic meter of air
per minute,i.e. it has the effect of a vacuum cleaner. The ambient
air is sucked into machine and most of the fly and dirt contained
in it is deposited on the EliTe Q Machine. Although EliTe Spinning
Machines generate considerably less fly than standard ring spinning
machines, they are soon covered with dust and fly if they are
installed in the same room as conventional spinning machines.
The fly has a negative effect on the yarn in the condensing
zone and the smooth running of the lattice apron. As a result,the
yarn is of substandard quality.
Rule .:EliTe Q Spinning
Machines must be separated from conventional spinning machines.
2.Spinning room conditions: The
fibres in the condensing zone are exposed to the room conditions
without any protection. Our recommendations on the room conditions
suitable for processing cotton and man-made fibres should be
followed, therefore. If the air humidity is too high, there
will be a higher tendency towards roller laps. If the air is
too dry,t here will be more fly. If the room temperature is
too high, there will be higher friction values and premature
wear.
Rule 2:maximum room temperature:33
.C
humidity should be
- max...,5 g water/kg air
for cotton
- min.9,0 g water/kg air for
cotton
- max..0,0 g water/kg air
for synthetics
- min.9,0 g water/kg air for
synthetics
3.Position of the Eli Top in
relation to the front bottom roller of the drafting system:
If the setting is correct, the top edge of the suction slot
in the Eli Tube is precisely set at the nip line of the delivery
top roller. If the nip line cuts the slot, condensation is impaired.
The hairiness of the yarn increases and the tearing strength
is reduced. If the nip line is behind the slot, part of the
spinning torsion may get into the condensation zone, resulting
in an increased ends-down rate and damaged lattice aprons.
Rule 3:The front top roller
is precisely 3.5 mm offset towards the operator in relation
to the front bottom roller of the drafting system.
4.Traverse mechanism: The
roving must run over the slot in such a way, that, from the
operator ’s view, the fibres move from the top right to
the bottom left. If the fibres run over the slot top from the
L.H. side,they make an S-shaped movement causing a certain unsteadiness
in the condensing zone. This has a negative effect on the yarn
values.
Rule 4:The traverse mechanism
for the sliver should be adjusted in such a way that the traverse
motion at the front of the drafting system does not exceed 4
mm,and that the l.h.limit position of the sliver is level with
the L.H..edge of the top of the slot.
5.Cleaning the Eli Tubes
and lattice aprons :Eli Tubes and lattice aprons are the most
important components of the EliTe Q Condensing System. Careful
maintenance is an important prerequisite for optimum yarn values.
In the centre area, where the suction is active, a permanent
air flow keeps the lattice aprons clean. To the left and right
of this area, the lattice apron can be clogged by fine dust.
With the time, this results in a considerable increase of the
friction between the lattice aprons and the EliTube. If
this friction is too high, erratic running of the lattice apron
and substandard yarn quality is the result. Therefore,lattice
aprons and Eli Tubes should be removed from the machine from
time to time and cleaned. This
can be done when the machine is
running. The time needed per box length is 5 min. The expenditure
of time necessary for changing the EliTubes with lattice aprons
is about 90 minutes for a machine with .1008 spindles,
which corresponds to a loss of production of 90 minutes.
For yarn count Ne 40, the production loss involved is less than
370 g. The cleaning frequency varies depending on the portion
of fine dust of the cotton. As an average value, 500 operating
hours may be taken into account. The aprons are cleaned in a
washing machine or in an ultrasonic cleaning device.The EliTubes
are cleaned using a damp piece of cloth. Damaged lattice aprons
must be replaced. On EliTubes with considerable traces of wear,
the inserts must be replaced.
Rule 5:Lattice aprons and
Eli Tubes must be cleaned from time to time.
6.Measures to be taken in the
case of laps at the front top roller Laps may occur in the case
of unsuitable room conditions or damaged or inappropriately
buffed cuts, or if the fibre material used is prone to the formation
of laps. Large laps may block the delivery and front rollers
and damage the cot of the blocked roller. If spinning is continued
with damaged cots,periodic yarn faults will be the result. Consequently,
a blocked Eli Top must be replaced by a new Eli Top and repaired
in the service room. For this purpose,all operators should carry
a spare Eli Top with them.
Rule 6:EliTops with blocked
top rollers must be replaced by new top rollers.
7.Buffing the EliTe Q Top Rollers
: The cots of the EliTe Q Top Rollers are subject to wear and
should be buffed from time to time.The tension draft in the
condensing zone –6 %as a general rule depends on the difference
in diameter between the front top roller and the delivery top
roller. Changed tension drafts may result in changed yarn parameters.
Rule 7:Make sure that the
difference in diameter of the front top roller and the delivery
roller corresponds precisely to the desired tension draft.
8.Checking the partial vacuum
As a general rule,continuous control of the vacuum pressure
is not necessary. When the whole machine is cleaned, we recommend,
however,to remove also the connecting hoses between the suction
tubes and the fans and to clean them.
Rule 8:Clean the connecting
hoses with regular frequency.
9.Maintenance of the fans:
Fans may be clogged after a time,which has a negative effect
on the suction.
Rule 9:The fans should
be removed from the machine and cleaned once a year.
10.Spinning speed: In the
case of EliTe Q Spinning Machines, return on investment is not
based on higher production, but on the production of yarn of
supreme quality. The Suessen recommendations concerning
traveller speeds and running-in speeds for rings and travellers
should be followed, therefore. Not the ultimate increase in
speed, but the yarn quality leads to success.
Rule
10:Yarn quality is more important
than quantity.