ICAC 62nd Plenary Meeting Gdansk, Sept. 7-12, 2003 Rieter Textile SystemPage 1 (5) Speaker: H Eberli

The New ComforSpin®- Machine K 44 -Competence in Spinning

H. Eberli, Rieter Machine Works Ltd., Winterthur Switzerland

1 Market overview of spinning systems

1.1 Market of the main Spinning Systems

To introduce the topic of my presentation let me start with a condensed overview of today’sspinning systems. The graph shows a breakdown of short staple yarns spun on ring spinningframes in tons produced respectively in spindle capacity against the yarn count.

A total of 21.1 mio tons requires a spindle capacity of 157 mio units. The big bulk of ring yarnis spun in the range of Ne 12-24, however, the peaks in spindelage we find in the region ofNe 18 -40.

Fig. 1

If we add the other 2 spinning technologies that are in use today we can notice that ringspinning reflects still the largest share. With this 21 mio tons approx. 75% of the short stapleyarns are spun with ring frames. Two thirds of the total number of 157 mio spindles areprocessing combed material, the other third is still fed with carded material.

On top of this ring capacity we have according to the ITMF statistics approx. 40 mio spindleequivalents in form of rotors. We assume that today one rotor equals 6 ring spindles.Therefore these 40 mio Equivalents represent 6.5 mio rotor positions.

Some 20 years ago one of our competitors started to sell air jet machines. We guess thattoday approx. 3 mio spindle equivalents are processing yarn in the range of Ne 20 to 40. Thistechnology has meanwhile reached a productivity factor of 14-17 times ring spinnperformance.

1.2 Market of ComforSpin® machines

What I wish to point out today is the effort Rieter has put in the field of enhancing thetraditional ring spinning system by applying specific elements to the drafting zone. In brief Iwill focus on the COM4® yarn spinning technology the first and only system that provides fullycompacted ring yarn of outstanding quality features.

Fig. 2

ICAC 62nd Plenary Meeting Gdansk, Sept. 7-12, 2003 Rieter Textile SystemPage 2 (5) Speaker: H Eberli

Worldwide, more than 600 ComforSpin® machines are in use predominantly in the medium tofine field of combed cotton yarns. We assume that this field of application will keepexpanding.

Fig. 3

2 ComforSpin® Technology

The increasing demand for reduction in hairiness of ring yarns is achieved with aerodynamicparallelization and compacting of the fibers after the main draft. The significantly betterintegration of edge fibers, resulting from compacting, and the spinning triangle which hasbeen reduced to a minimum, not only result in a reduction in hairiness but also in improveddynamometric and yarn evenness values, as well as in fewer imperfections. Practicalapplication has impressively confirmed the favorable influence of compacting on runningbehavior and quality during down stream processing stages, as well as on the wearproperties of the end product.

Fig. 4, 5

In the Rieter ComforSpin® process, the compacting device necessary to achieve thisessentially consists of a perforated drum with a fiber-specific suction insert, a speciallydesigned air guide element and an additional nip roller (Fig. 6 and 7).

Fig. 6, 7

The ComforSpin® system features a modular construction, which can be adapted accordingto the technological characteristics of the fiber material. The surface structure of theperforated drum installed on the delivery cylinder can be specified for coarser or finer yarnranges. In addition, the surface structures are selected such that a wide area of overlapensures the necessary flexibility for processing various raw materials and yarn counts.

3 COM4® Yarn Characteristics

3.1 COM4® Structure

Immense differences in the yarn structures of ring-spun and compact yarn are to be seenunder the microscope.

Fig. 8

The ring yarn structure reveals itself to be far less perfect than is generally assumed. Thelong, protruding fibers of conventional ring-spun yarn are the cause of a number of problemsin downstream processing.

In contrast, compact yarn shows all fibers twisted in and contributing to yarn strength, makingfull use of the fiber properties. The result is exceptionally low hairiness combined with higheryarn strength and elongation.

ICAC 62nd Plenary Meeting Gdansk, Sept. 7-12, 2003 Rieter Textile SystemPage 3 (5) Speaker: H Eberli

Fig. 9

Compact yarn enables either reduced twist or enhanced strength to be exploited indownstream processing and therefore has a positive influence on subsequent processingstages. This provides a high degree of flexibility, since the yarn can be adapted to therequirements of the subsequent end product. The much higher strength of compact yarnscan be exploited for shirting fabrics. Twist can be reduced by up to 15% when manufacturingT-shirts, where the emphasis is on soft handle. And lower twist means higher production forthe spinner.

3.2 COM4® in Downstreamprocessing

Many qualitative and economic advantages of compact yarns come into their own indownstream processing. The lower hairiness of COM4® yarns reduces the clinging tendencyduring weaving, which allows reducing the amount of size in the weaving preparation.

Fig. 10

In the field of knitted fabrics fiber fly and therefore foreign fibers can be reduced up to 55%,depending on the twist reduction of the COM4® yarn.

Fig. 11

The higher yarn strength results in a reduced thread break frequency and stands also forhigher production speed, better operating reliability and reduced finishing costs. Woven orknitted fabrics made from compact yarns are characterized by clear, visible structures andimproved durability.

In addition to improved efficiency and lower process costs, new products can also becreated, thus opening up a wide range of potential applications. There will be many morepossibilities for exploiting the economic benefits of the potential of the new technology.

ICAC 62nd Plenary Meeting Gdansk, Sept. 7-12, 2003 Rieter Textile SystemPage 4 (5) Speaker: H Eberli

4 New Applications of COM4

4.1 COM4 Core Yarns

Core yarns are produced all over the world on an increasing number of ring spinning frames.In the past, the demand for core yarns has been driven by strongly fluctuating trends infashion. Over the last ten years, however, this segment has made a strong comeback,particularly with elastic filament cores. Rieter's ComforSpin® process now allows manufactureof even fine compact-core yarns of the highest quality level.

Compact-core yarns with an average yarn count of up to approx. Ne 40 (Nm 67) are not new.But the production of finer and the finest compact-core yarns is a relatively new field andplaces the most stringent demands on the compacting system. Precise insertion of theelastomer core into a compacted fiber structure comprising a relatively small number of fibersrequires stable geometric conditions in the drafting system. Complete fiber control in thecompacting zone and a spinning triangle that is reduced to the minimum size areindispensable here, as is the high consistency of quality attained through the ComforSpin®

process with its rotating perforated metal drum.

Fig. 12

Fine compacted core yarns are processed on circular knitting machines for high-qualityunderwear and also have considerable potential in "seamless" processing for hosiery andbodystockings. The yarns are also in demand for weaving, both warp and weft, on account oftheir low hairiness and an increasing requirement for elasticity. Interest is concentratedmainly on shirts and women's outerwear.

4.2 Outstanding compacting characteristics with wool

The fact that when compared to cotton fibers, woolen fibers have considerably less strengthbut better elongation virtually makes wool a natural for use in the compacting process. Rieter,in conjunction with Cognetex, the Italian manufacturer of long-staple machines, developedthe ComforSpin® process for processing wool. The ComforSpin® elements were adapted tothe specific requirements of wool and constructively integrated into the wool spinningmachine "IDEA" by Cognetex.

Fig. 13

Practical application has shown that compacting results in an improvement in the yarnvalues, which is better still than is the case with cotton or other short-staple fibers. With thenatural characteristics of wool, namely low strength and considerable elongation, animprovement in yarn strength is very interesting economically, for the very reason thatspinning becomes possible at significantly increased spindle speeds. In the wool industrythere is thus an assumption that in the long-staple field, the market share of compactspinning machines is increasing significantly faster than in the short-staple field.

ICAC 62nd Plenary Meeting Gdansk, Sept. 7-12, 2003 Rieter Textile SystemPage 5 (5) Speaker: H Eberli

5 Summary

For compact yarns Rieter assumes the following trends and chances.• COM4 yarns are well established in the weaving yarn market (shirting, bed linen) and the

advantages are well known thanks to the marketing campaign of Rieter.• The advantages in the field of knitting are not yet known in the market, but the yarn

properties also show advantages in knitting processes• Increasing processing speed in weaving and knitting require for yarns with higher

strength and elongation properties• Ply yarn is increasingly replaced by compacted single yarn• Various producers optimize their yarns in the fields of raw material and twist factor by

making use of the compact technology• Demand and market share for compact yarns are on the rise - both in Europe and Asia• The share of compact yarn will further rise with new applications (blends, wool, core yarn)

Fig. 14

H. EberliICAC, September 10, 2003 Rieter Textile Systems1

Short Staple Spinning - Market Structure Ring

Spinning Capacity (t/y) by Yarn Counts 2001

0

500

1'000

1'500

2'000

2'500

3'000

3'500

4'000

4'500

5'000

6 12 18 24 30 35 41 47 53 60 66 73 80 100

Yarn count in Ne

Yar

n pr

oduc

tion

in 1

'000

t

0

5'000

10'000

15'000

20'000

25'000

Num

ber

of s

pind

els

x 1'

000

Yarn production (when world short staple ring yarn production is 22,4 Mio tons) Operating ring spindles x 1'000

157 Mio Spindles

21,1 Mio tons

H. EberliICAC, September 10, 2003 Rieter Textile Systems2

Short Staple Spinning - Marketstructure

Spindle Equivalents by Yarn Counts [2002]

Operating ring spindles x 1'000

0

5'000

10'000

15'000

20'000

25'000

6 12 18 24 30 35 41 47 53 60 66 73 80 100

Yarn count in Ne

Num

ber

of s

pind

els

x 1'

000

Operating ring spindles x 1'000

Rotor40 Mio

Ring157 Mio

Ring combed101 Mio

Ring carded56 Mio

Airjet3 Mio

H. EberliICAC, September 10, 2003 Rieter Textile Systems3

Phase I - III: 100% combed cotton Ne 30 - 80 ~600’000 spindles sold

150‘000 K 40 spindles

+ 120’000 K 44 spindles

Europe

Europe

Turkey

India

Egypt Pakistan

China

Thailand

Indonesia

+ Asia

+ 330‘000 K 44 spindles

- Market Development (1)

H. EberliICAC, September 10, 2003 Rieter Textile Systems4

Operating Principle Ring spinning - ComforSpin®

Comparison of the operating Principles

Ring spinning ComforSpin®

b

B

b

B

Bring = BCOM4bring > bCOM4

H. EberliICAC, September 10, 2003 Rieter Textile Systems5

- Compacting Elements (1)

K 44 Weighting Arm with compacting Elements

compacting zone

H. EberliICAC, September 10, 2003 Rieter Textile Systems6

Compacting Elements (Air Guide Elements inserted)

air guide bracket

air guide element

- Compacting Elements (2)

H. EberliICAC, September 10, 2003 Rieter Textile Systems7

Suction Inserts - Flexibility in Applications

suction insert

suction slot

- Compacting Elements (3)

H. EberliICAC, September 10, 2003 Rieter Textile Systems8

- Yarn

- The perfect Yarn Structure

• low hairiness

• higher strengthand elongation

• less fibre fly

• no singeing

• reduced sizing

• no waxing

Ring yarn

H. EberliICAC, September 10, 2003 Rieter Textile Systems9

Comparison of weak Points

Elongation [%]

Highest strength [N]

2 4 6 8

100% cotton combed; Ne 60, αe 3.56

Ring yarn

- Yarn Strength

H. EberliICAC, September 10, 2003 Rieter Textile Systems10

Better Efficiency despite lower Amount of Size

Sizingdegree:100%

75%

50%

25%

Stops/100‘000 picks

0

1

2

3

4

5

6

7

8

Warp + weft

3.0/100‘000

Ring yarnαe 3.56

coul

d no

tbe

proc

esse

d

αe 3.56 αe 3.23 100% CO, Ne 60

- in weaving Preparation

H. EberliICAC, September 10, 2003 Rieter Textile Systems11

Lower Fibre Fly and less Foreign FibresFibre fly [%]

- 55%

0

20

40

60

80

100

Ring yarnyes

100%no

90%yes

100%no

100%yes90%twist:

waxed:

- in Knitting

H. EberliICAC, September 10, 2003 Rieter Textile Systems12

Core Yarns produced with a superior Compact System

- New Applications (1)

• stable, geometric conditionsin the drafting zone

• entire fiber guidance duringcompacting

• spinning triangle reducedto a minimum

• high quality constancywith rotating metal cylinder

• equal terms from spindle tospindle over the whole lengthof machine

H. EberliICAC, September 10, 2003 Rieter Textile Systems13

COM4 wool - worsted Compact Yarn

- New Applications (2)

• implementation of theComforSpin® systemin long staple ring spinningmachine IDEA by Cognetex

• replacement of nip rollerby special elastic control roller(barrel shape) on slant axisfor negative draft

H. EberliICAC, September 10, 2003 Rieter Textile Systems14

Market outlook for compact yarns

• Advantages in the field of knitting are not yet known in the market

• yarns are well established in the weaving yarn market(shirting, bed linen)

• Increasing processing speed in weaving and knitting require foryarns with higher strength and elongation properties

• Ply yarn is increasingly replaced by compacted single yarn

• Various producers optimise their yarns in the fields of raw materialand twist factor by making use of the compact technology

• Demand and market share for compact yarns are on the rise - bothin Europe

• The share of compact yarn will further rise with new applications(blends, wool, core yarn)

- Trends - Chances