Card C 60 –Technology and Flexibility

for the Future

3

IntroductionRieter designed the new C 60 high-performancecard to fulfill our customers’ high standardsfor their carding processes.

The innovative C 60 incorporates new conceptssuch as increased working width, increasedcarding angle, smaller cylinder diameter, modu-larity for easy maintenance and our IntegratedGrinding System (IGS). All of these conceptsresult in higher productivity, significant lowdowntime, high and consistent sliver quality,increased trash reduction and overall increasedefficiency. In addition, the C 60 has an outputof up to 180 kg/h, increasing production ratesfor all applications.

Packed with all these features the C 60 meetsthe demands of today as well as the future.

Initial experience on the marketDuring our market launch of the C 60 high-performance card, the C 51 card will continueto be manufactured and sold. Approximately600 C 60 cards have been delivered to date.Fig. 1 summarizes the main features of thenew C 60 high-performance card.

An initial market analysis shows that the C 60cards are represented in all yarn manufactur-ing processes for short staple spinning.

Card C 60 – Technology and Flexibility for the Future

• At least 50% higher output than the C 51• Output up to 180 kg/h• Card sliver weight of 5–20 ktex• Single or triple licker-in (interchangeable)

• Process integration of drawframe withSB/RSB module and up to 5-fold draft

• Modular concept for easy maintenance• Unchanged space requirements

Fig. 1:Summary of the main features of the new C 60high-performance card

Dr. Götz GresserMaschinenfabrik Rieter AG

Fig. 1

Summary of the main features of the new C 60 high-performance card

4

Output in kg/h

Yarncountin Ne

(drafting without levelling) (drafting with levelling)C 60 SB (14%) C 60 RSB (12%)C 60 (74%)

0102030405060708090

100

0 20 40 60 80 100 120 140 160 180 200

Yarncountin Ne

Output in kg/h

0102030405060708090

100

0 20 40 60 80 100 120 140 160 180 200

Triple licker-in (48%)Single licker-in (52%)

combed ring-spunyarns

carded ring-spunyarns

rotor-spun yarns

Fig. 2:Current deployment of the C 60 – usingdifferent coiling systems as a function ofoutput and yarn count

Fig. 3:Current deployment of the C 60 – usingsingle and triple licker-in units as a functionof output and yarn count

C 60 coiling systems, a function of output and yarn count

Fig. 2

C 60 single or triple licker-in, a function of output and yarn count

Fig. 3

cess. Currently, the direct process is used exclusively for rotor spinning with cotton or when processing recycled material. In thecase of the C 60 SB card (drafting systemwithout auto-levelling) and the C 60 (CBAcoilers with standard linear changer), one ormore additional drafting processes are alwaysused. The widely used CBA coiler with sliverweights up to 12 ktex predominates here. CBA coilers are used across the entire pro-duction and yarn count range, covering almostthe entire ring-spun yarn sector. The applica-tions of the C 60 SB and C 60 RSB cards arein high card output levels. The C 60 SB cardsare being used for yarn counts of up to Ne 40and the C 60 RSB cards are used more in thedirect process, usually up to Ne 25.

The integration of a full-scale drafting processin the card has now become established forcertain yarn applications where importance isgiven primarily to shorter processes in orderto increase the spinning mill’s profitability.

The C 60 card is available in different versions.One option is to equip the C 60 with single or triple licker-in units, depending on the re-quired yarn quality and yarn count. The finerthe yarn and the lower the card output, themore often the single licker-in is used (Fig. 3).Production rates of up to 80 kg/h are achievedfor combed ring-spun yarns. The triple licker-in comes into its own in the high output range,where higher trash removal and intensiveopening are necessary.

For fine ring-spun yarns, our experience withmore than 10,000 cards of the C 4 to C 51generations that have already been delivered,indicates that a triple licker-in is more inclinedto be a drawback compared to a single licker-in. This is again confirmed by the findingsgathered to date with the C 60.

Another new feature of the C 60 card is that avariety of coiling system can be used based on process requirements (Fig. 2). As an alter-native to the classical CBA coilers a coiler witha full-scale drafting system can be used.

The C 60 RSB card (autoleveller draftingsystem) is used primarily for the direct pro-

5

Technological review and resultsA machine’s success in terms of technologydepends on the interaction of all the elementsinvolved in the carding process. Only homo-geneous batting produces a uniform sliver.Homogeneous batting results in uniform open-ing of the fibrous material in the licker-in zone and results in superior carding in thecylinder zone.

Therefore, much attention was given onproducing homogeneous batting in the devel-opment of the feed chute for the C 60 card (Fig. 4). The controlled, additional opening ofthe fibrous material and the use of air for active,constant compression of the fibrous materialprevent large clumps of fiber from reachingthe card. It is a pre-requisite for successfullycompacting it into homogeneous batting.

Fiber mass on the cylinderFiber mass on the cylinder is of central impor-tance for carding quality. The higher the fibermass on the cylinder, the lower the fibercarding intensity, since the carding surface perfiber is reduced. The available carding surfaceis thus a significant determining factor forsliver quality.

Sliver and yarn quality decline at increasingoutput rates, which are equivalent to increasedfiber mass on the cylinder. The new C 60 high-performance card capitalizes on this basicfinding. The increase in working width from 1 mto 1.5 m enables the fiber mass on the cylin-der to be increased by 50% without having to reduce the carding surface per fiber at thesame time.

Fig. 5 schematically compares the carding sur-face per fiber using cards 1 m or 1.5 m widewith a 50% increase in output. The output ofthe C 60 card is increased at a stroke by 50%without any loss of sliver and yarn quality inthe process.

Openingcylinder

Activeair

supply

Feedingtrough

Homogeneous batting from the feed chute

Fig. 4:C 60 feed chute – controlled additionalopening and compression of the fibrousmaterial to produce homogeneous batting

Fig. 5:Benefits of the working width of 1.5 mcompared to 1 m as regards to fiber coverage on the cylinder

Additional opening and compression for homogenous batting

Fig. 4

or+ 50% output at the same quality

Increased production

33% lower fiber coverage

Improved technology

Trommel

1 m

Fiber coverage on the cylinder

Outpute.g. 100 kg/h Output

e.g. 100 kg/h

Outpute.g. 150 kg/h

Trommel

1.5 m

cylinder

Working width of 1.5 m compared to 1 m regarding fiber coverage

Fig. 5

6

100 cm 150 cm

doffer web doffer web

5 90 5 5 140 5

Utilization of working width in cm

Output in % 100 100 + 50 + 5.5

90 140 (90 + 45 + 5)

Increase in output from 1 m to 1.5 m + 55.5%

• Carding segments

• Extraction blades

• Covering profiles

• Flats

Fig. 6:Comparison between cards 1 m and 1.5 m wideregarding web coverage on the doffer

Fig. 7:Use of aluminum profiles on the C 60 card

Doffer web coverage: working width of 1.5 m compared to 1 m

Fig. 6

C 60 aluminum profiles, state-of-the-art precision

Fig. 7

Technically, the increase is greater than 50%since the utilization of the doffer’s workingwidth by the web is higher on the C 60. The web coverage on the doffer shows thatthere is usually a strip of 3–5 cm on the edgezone of the doffer that is not covered by theweb (Fig. 6). In relation to the theoreticallyavailable working width of the doffer, thismeans that the web width on the doffer actu-ally utilized on the C 60 card is 53–55.5%higher than on a card 1 m wide.

The above points are undisputed. However,they presuppose that the precision of the ele-ments involved in the carding process andtheir operation are the same as for a 1 m card.Only then are the same settings and the samecarding intensity possible.

Precision of the elements on the cylinderIn the development of the C 60 card specialattention was paid to the precision of the cardelements. For example, state-of-the-art alumi-num profiles are used for all knife holders, flats,carding segments and covering profiles (Fig.7).

The advantage of this is high precision manu-facturing. A further advantage is the reductionin the weight of the components, which comesinto its own primarily during maintenancework. Since we impose high standards of pre-cision on the parts used, the aluminum pro-files in contact with the fibrous material arespecially processed so that they vary by only a few hundredths of a millimeter across theworking width of 1.5 m.

The closest attention with regard to precisionis given to the flats. They are the core elementsof the carding process in the cylinder zonewhere quality is concerned. The flats of the C 60card have the same variations across theirworking width as those on the C 51 (Fig. 8).This means that they are virtually flat. In termsof the entire set of flats with the clothing, thetotal variation is in a range of a few hundredthsof a millimeter.

7

The cylinder is subjected to high peripheralspeeds of up to 40 m/sec with very small gaps of only 0.1 mm relative to the elementsaround the cylinder. Concentricity errors andcylinder bulge must therefore be kept as smallas possible. Fig. 9 shows the concentricityerror and bulge in the C 60 cylinder withoutclothing at rotation speeds of up to 1000 rpm.The C 60 card has a total concentricity error,which remains constant even at high rotationspeeds and is very small. Cylinder bulge is a function of centrifugal force. It increases athigher speeds. Compared to the C 51, theconcentricity error and bulge of the cylinder of

Flats without clothing Flats with clothing

Entire set of flats virtually level (as on the C 51) Entire set of flats a few hundredths of a millimeter

• Very high precision for good carding results

Fig. 8:Precision of the flats with and without clothing

Fig. 9:Comparison of cylinder concentricity errorand cylinder bulge on the C 51 and C 60

C 60: precision of the flats with and without clothing

Fig. 8

0%

20%

40%

60%

80%

100%

0 200 400 600 800 1000

Cylinder bulgewithout clothing

Range of application

Cylinder rotation speed in rpm

C 60

C 51

0%

20%

40%

60%

80%

100%

0 200 400 600 800 1000

Cylinder rotation speed in rpm

Range of application

C 60

C 51

Concentricity errorwithout clothing

• Each cylinder on the C 60 card is manufactured and tested to the highest precision• The cylinder on the C 60 card is more accurate than that on the C 51 card

Comparison of cylinder concentricity and bulge error on C 51/C 60

Fig. 9

the C 60 card are much smaller. All the stepstaken ensure that not only accurate, but alsofine settings can be made, just as on othercurrent cards.

Web formation on the dofferWeb formation on the doffer takes place in the transfer zone, defined as that zone betweenthe cylinder and the doffer where the fibers are transferred from the cylinder to the doffer.The transfer zone is important to the cardingprocess because faults in the web pass directlyinto the ongoing process (e.g. neps, trashparticles or variations in mass).

8

Fig. 10:Comparison of the transfer zone between cylinderand doffer on the C 51 and C 60

Fig. 11:Comparison of the transfer factor and fiber masson the cylinder between the C 51 and the C 60 at the same output

ferred to the doffer with each revolution of thecylinder. If the transfer factor were 100%, allthe fibers on the cylinder would be transferredto the doffer upon contact with it. In fact, an“interim stock” of fibers forms on the cylinder.The transfer factor is usually between 5% and15% [2].

Many factors, such as production rate,influence transfer. Fig. 11 gives a schematicrepresentation of the transfer factor as afunction of output at constant sliver weight. As output increases, the transfer factor rises. However, higher fiber masses on the cylinderhave an adverse impact on card sliver results.Even if a card 1 m wide could equal the outputof the C 60 card, it could not match the lowertransfer factor achieved by the C 60 card. At an output of 120 kg/h, for example, the card1.5 m wide has a lower transfer factor than the card 1 m wide, since the distribution of thefiber web on the cylinder corresponds to anoutput of 80 kg/h.

The fibers on the C 60 card remain on thecylinder longer, compared with a 1 m card,and can be carded more intensively, leading toan improvement in technology results.

Another way of illustrating the influence of thetransfer factor is via the distance traveled bythe fibers on the cylinder. The longer the dis-tance the more intensively the fibrous materialis carded. The transfer factor on the C 60 cardfor the example chosen with an output of 120 kg/h is approx. 3% lower than on the C 51.Fig. 12 shows a comparison between thedistance traveled by fibers on the cylinder ofthe C 51 and the C 60 at the same output. The advantage of the lower transfer factor onthe C 60 compensates in full for the smallercarding circumference on the cylinder due toits smaller diameter. This ensures that thefibrous material is subjected to the samecarding intensity as on the C 60. The smallercylinder diameter results in no technologicaldisadvantages.

C 60 = C 51

Transfer zonecylinder/doffer

C 60

C 51

C 60

C 51

Comparison of the transfer zone between C 51 and C 60

Fig. 10

Transfer factor (ÜF)in %

Output in kg/h

C 51 80 120C 60 (C51+50%) 120 180

Card sliver weightin ktex, C 51/C 60

5.0/7.5

C 60

C 51ca. 3 %

C 60

Fiber mass on thecylinder in g/m2

Output in kg/h

C 51 80 120C 60 (C51+50%) 120 180

Card sliver weightin ktex , C 51/C 60

5.0/7.5C 51

• ÜF C 60 < ÜF C 51 at the same output• Fibers revolve more often on the C 60

• Fiber mass C 60 < fiber mass C 51• Carding surface per fiber higher on the C 60

Comparison of transfer factor and fiber mass between C 51 and C 60

Fig. 11

Due to the major importance of the transferzone, the focus was on ensuring that its lengthwas identical to the length of the C 51. The use of a larger doffer compared to the C 51 compensated for the smaller cylinderdiameter (Fig. 10).

The transfer factor quantifies the proportion ofthe fibrous mass on the cylinder that is trans-

9

Technological resultsThe results achieved in spinning mills greatlysupport the above-mentioned technologicalconsiderations. The variety of raw materialsand applications used in day-to-day spinningmill operations show that the new machineconcept meets the technological demands.Various applications are examined more indetail below.

Fig. 12:Comparison of the distance traveled by thefibers on the cylinder of the C 51 and the C 60at the same output

Fig. 13:Customers’ production levels for different rawmaterials with rotor-spun yarns

Rotor-spun yarn

020406080

100120140160180

Outputin kg/h

Denim

yarn

PES/co

tton b

lend

Regen

erated

cotto

n

60 m

m polyp

ropyle

ne

Knittin

g yarn

Fig. 13

Rotor yarn: customers’ production levels for differrent raw materials

C 51 and the C 60 at the same output

C 51

C 60

Distance traveled by the fiberson the cylinder

20.8 m

21 m

7.7 revolutions

10 revolutions

Transferfactor in %

13

10

Carding circumferenceC 60: 2.10 mC 51: 2.70 m

Distance traveled by the fibers on the cylinder at the same output

Fig. 12

• Same carding intensity despite smaller cylinder• No technological disadvantage due to smaller cylinder

Rotor-spun yarnThe production range for rotor-spun yarnsusing the C 60 in the spinning mill is usuallybetween 80 and 180 kg/h. Depending on theapplication, different maximum outputs areachieved (Fig. 13). In the denim yarn sector(Ne 10 cotton) and for coarse man-made fiberyarns (Ne 6 PP), the C 60 achieves itsmaximum output of 180 kg/h, previously aninconceivable range for rotor-spun yarns. In the process, increases in output comparedwith the C 51 card and the reference cards are being achieved amounting to more than150% in the case of the C 51 and up to 300%with older cards.

10

01020304050607080

Output Thin –50% Neps Elongation %

C 51 C 60

Noil Thick +50% Strength RKM

Customer in AsiaCombed ring-spun yarns, Ne 40 with Indian cotton (28–34 mm)

Fig. 14:Technology results for fine combed ring-spunyarns compared to Uster® Statistics

Fig. 15:Comparison of technology results for finecombed ring-spun yarns from the C 51 and C 60 Fig. 15

Ring yarn: combed Ne 40

0.61

15.3

36.7

1.9

17

36

0

10

20

30

40

Thin (–50%) Thick (+50%) Neps (+200%)

C 60 Uster® 5%

Customer in EuropeCombed ring-spun yarns, C 60 card, 47 kg/h, E 62 comber,K 44 ring spinning machine, high-quality Ne 50 yarn (COM4®)

Fig. 4

Fig. 14

Ring yarn: combed Ne 50

Since the C 60 has already successfullyestablished itself on the market for rotor-spunyarn applications due to the “Rieter RotorSystem = C 60 + R 40” [1] – we shall refrainfrom presenting detailed results in this paper.

Ring-spun yarnThe C 60 is currently at home in all applica-tions, both for coarse carded and for fine-combed ring-spun yarns. Customers’ output

levels are between 40 and 120 kg/h in a count range usually between Ne 12 and Ne 80. Fig. 14 and Fig. 15 show successful yarnresults of customers in Europe and Asia forfine-combed ring-spun yarns. Yarn results inregard to uniformity, imperfections and yarnstrength are equal to the C 51 card but achievedat more than 150% of the production perfor-mance of the C 51 card.

11

Processing man-made fibersC 60 card production rates for man-madefibers are second to none. A few examples aregiven with Fig.16.

Fig. 17 shows a comparison of the yarn results of a drawframe sliver blend of finepolyester/cotton ring-spun yarn using the C 60 card and the C 50 card. Better yarnvalues are achieved using the C 60, with a substantial increase in output. Yarn results

020406080

100120140160

Ring-spun polyester38 mm, 1.2 den

Rotor-spun polypropylene 60 mm, 4.6 den

PES/CO65/35%

Airjet PE38 mm, 1.2 den

Airjet microfiber 38 mm, 0.8 den

140 180 140 90 75

Outputin kg/h

180

Man-made fibers

Fig. 16:Customers’ production levels for different man-made fibers

Fig. 17:Comparison of technology results forpolyester/cotton ring-spun yarns

Fig. 16

Man-made fibers: customers’ production levels

Customer in Asia 65% PES, 38 mm / 1.2 den (1.3 dtex),Ne 45 ring-spun yarn, 35% cotton, 1 1/8“

0

20

40

60

80

100

120

140

160

Output(kg/h)

CVm % Thin–50%

Thick+50%

Neps+200%

Strength(cN/tex)

C 50C 60

Fig. 17

Ring yarn: polyester cotton blend Ne 45

are also very good in the case of tuft blends of cotton/polyester in fine rotor-spun yarns(Fig. 18).

The successes in processing man-made fibersare not attributable to solely the card. Theadditional opening of the fiber tufts in the chuteshows technological advantages especially in the case of man-made fibers, where highopening forces are required, as shown in Fig. 4.

Air vortex spinningThe C 60 card has demonstrated that it canproduce good results when used with this newspinning process. Fig. 19 shows that the C 60 card recorded better yarn values at twicethe output.

FlexibilityRieter’s C 60 card concept includes rapid set-up, servicing and maintenance times.Modularity and process optimization are twoimportant factors in the new C 60 cardconcept.

12

Fig. 18:Comparison of technology results for aPES/cotton blend for rotor-spun yarn

Fig. 19:Technology results for air vortex spinning withpolyester

0

5

10

15

20

25

Thin–50%

Thick+50%

Neps+200%

StrengthcN/tex

Reference 32 kg/h

C 60 68 kg/h

Figures are 3-monthaveragesC 60 with single licker-in 0 0

Customer in the US Air vortex results, 100% polyester, Ne 20

Air vortex yarn: polyester Ne 20

Fig. 19

Customer in Europe 50% PES, 38 mm / 1.2 den (1.3 dtex),Ne 30 rotor-spun yarn, 50% Co, 1 1/16“ / 4 Mic. (UNIblend A 80 blend)

0

50

100

150

200

250

300

350

400

450

Output(kg/h)

CVm% Thin–50%

Thick+50%

Neps+280%

Strength(cN/tex)

ReferenceC 60

Rotor yarn: polyester cotton blend Ne 30

Fig. 18

ModularityThe modular structure of the C 60 card offers the advantage of easy adaptation to dif-ferent tasks. Fig. 20 illustrates the modularsub-assemblies of the C 60. Each subassem-bly can be exchanged rapidly within 11/2 hoursin order to keep downtimes very short. Theability to prepare the subassemblies in a sepa-rate maintenance area away from the machinelessens setting errors. When changing thelicker-in and doffer subassembly groups, onlyone setting has to be done on the card, i.e. thegap relative to the cylinder.

13

Fig. 20:Modular structure and subassemblies of the C 60 card

Fig. 21:Different configurations of the C 60 card as afunction of the raw material used

Flats module(1.5 h total for removal and installation)

Doffer module(1.5 h total for removal and installation)

Licker-in module(1.5 h total for removal and installation)

Flats module(1.5 h total for removal and installation)

Fig. 20

Fig. 2C 60: Modular structure and subassemblies

Cotton

Triple licker-in Single licker-in Pre- and Post-carding

Triple licker-in Single licker-in

Man-made fiberPre- and Post-carding

Fig. 21

Fig. 2C 60: Different configuration as a function of the raw material used

The modular structure also offers the option of changing from single to triple licker-in unitsor vice versa. This ensures that the flexibilityexists in the spinning mill for future processand raw material changes. For example, fromrotor-spun to ring-spun yarn or from cotton toregenerated fiber.

The C 60 card comes very close to being the universal card for all applications. Whenmaking technological changes, it is veryimportant that the carding and extraction ele-ments can be replaced individually, so that the technological optimum can be achieved.Fig. 21 illustrates the different configuration

14

versions of the C 60 card, depending on theraw material being used. For example, cardingsegments or cover profiles can be fitted atextraction blade positions or vice versa.

In the case of man-made fibers, mainly cardingsegments are used to prevent fiber loss and toachieve optimum opening of the material.

Another important factor is the automatic grind-ing of card clothing. Card clothing is subjectto severe wear. Manual grinding of card cloth-ing is a time-consuming maintenance task andis very labor-intensive. For many years Rieterhas equiped the cards with the IntegratedGrinding System (IGS). This provides for theautomatic grinding of cylinder clothing (IGS-classic) and flats clothing (IGS-top) (Fig. 22).IGS is also available for the C 60 card. Thecylinder and flats clothing is ground periodi-cally, automatically and without any loss ofproduction.

Every yarn manufacturer knows that there is a relationship between the condition of theclothing, nep reduction and trash removal.Sharp clothing removes/releases more nepson the flats and extracts trash particles moreeffectively since the fibers are retained on thecylinder. IGS keeps sliver quality constant in terms of nep content, and at the same time,the service life of the cylinder and flats cloth-ing is prolonged. Empirical values for the C 60 card indicate an increase of 30–50% inservice life.

Shorter processes depend on processoptimizationRieter has responded to customers’ require-ments with the C 60 card by putting coilersfeaturing full-scale drafting passes alongsideclassical coilers enabling the process to be shortened. Fig. 23 illustrates the currentcustomary shorter processes. The better the yarn quality required, the more draftingpasses have to be used. The direct process is a challenging process because this process

Fig. 22:Automatic grinding of cylinder and flats clothingusing the Integrated Grinding System (IGS)

Fig. 23:Process options using the C 60 card as afunction of yarn quality

IGS-classic and IGS-top

improve sliver quality

and extend the service

life of the clothing

Conventional3–4 grinding operations

IGS-classic400 grinding cycles

Microscope photocylinder clothing

Roundedtooth point

Constantly sharpcarding point

Cylinder clothingground with IGS

400 x

IGS-classic for cylinders IGS-top for flats

Fig. 22

Integrated Grinding System (IGS): for flats and cylinder clothing

Fig. 23

C 60 process options: a function of the required yarn quality

The processes are defined according to the yarn quality required

(4–6 cans)

Qual

ity o

f yar

n

15

in particular calls for control and optimizationof the process flows on the card and integrateddrawframe. The sliver coiled in the can must display high uniformity at all times,otherwise the efficiency of the rotor spinningmachine is reduced by more frequent thread breakages, resulting in visible qualitydifferences in the end product. Rieter made no compromises with regard to the processtechnology used when making the processshorter.

In the case of the C 60 SB card (drafting mech-anism without auto levelling) and the C 60 RSBcard (auto levelling drafting mechanism), thismeans that the successful drafting technologyof the Rieter drawframe has been adopted andoptimized for single sliver drafting. More than20,000 Rieter high-performance drawframesinstalled in the past 20 years bear witness totheir success. Fig. 24 shows the combinedcard/drawframe solution featuring the C 60.

In the case of the C 60 RSB card, particularattention was paid to can change in optimizingprocess flows. In contrast to the classicaldrawframe, the card can changes must beperformed while the card is running to avoidsliver breakage.

The combined card/drawframe solutionscurrently available on the market operate inslow motion (at creep speed) during canchanges, resulting in a very low sliver speedof approximately 10 m/min. The consequenceis deterioration in the sliver’s CV value andtechnological values. Can changes on the C 60 with the RSB module take place at a highsliver speed of 100 m/min. Furthermore, thelevelling actuation point as a function of thedelivery speed of the card sliver entering thedrafting system is adjusted automatically. Thissituation is illustrated in Fig. 25. The patentedsolution guarantees that sliver weight is con-stant at every stage during can change.

Fig. 24:Combined card/drawframe solution using the C 60 for the direct process

Fig. 25:C 60 RSB card – levelling actuation point as a function of the speed of the card sliver forconsistently high uniformity

• Proven technology of the Rieter RSB autolevelling drawframe

• 100% levelled card sliver even during can change

• Drafts up to 5-fold

• Rotating scanning roller with minimal friction

• Permits high contact pressure

Perfect uniformity

Fig. 24

Fig. 2C 60 direct process combines card and drawframe

97

100

103

106

109

112

0 50 100 150 200 250 300

Levelling actuation point in %Output 180 kg/hSliver weight 12 ktexCan change

Card sliver speed in m/min

Correction of the levelling actuation point as a function ofsliver speed guarantees high uniformity ot the card sliver at all times

Fig. 25

C 60 RSB: levelling actuation point follows the sliver speed

16

Fig. 26 shows the behavior of the sliver’s CVvalue, comparing the C 60 RSB card and aconventional combined solution operating atcreep speed. This ensures that the sliver’s CVvalue remains constant in the direct process,even at high production rates of 180 kg/h,where a can change takes place every 6minutes. For spinning mill operators, thismeans that they can utilize every meter in thecan for final spinning without having to expectany loss of quality.

Since shorter processes involve much morethan merely connecting up process stages,only optimization of the combined solutionultimately leads to success.

SummaryThe introduction of the new C 60 high-performance card with an output of 180 kg/hmeans that progressively fewer cards areneeded.

For this reason high standards are imposed interms of quality, reliability and availability. The following design features contribute to thesuccess of the system as a whole:

Modular structureThe subdivision of the card into interchange-able licker-in, flats and doffer modulesreduces maintenance effort and increases flex-ibility. For example, the triple licker-in can be exchanged for a single licker-in at any time.This means that the C 60 can be optimallyequipped and adapted to the raw material andtype of yarn to a hitherto unknown degree. A subassembly can be replaced in as little as11/2 hours.

Working width of 1.5 metersThe greater working width of the C 60 resultsin lower fiber coverage on the cylinder. This is what enables output to be increased withouthaving to accept compromises in end productquality. The combination of technology andmanufacturing quality from the card chute tothe coiler results in consistently high sliverand yarn quality, which is impressively demon-strated by the practical examples from milloperations.

Fig. 26:Comparison of sliver uniformity during canchange between the C 60 RSB card and asolution featuring can change at creep speed

Fig. 26

Sliver uniformity during can change

Variation in %(cut length measurement 1 m) Output of 150 kg/h

Sliver length in m

Can change

C 60 RSBOther approach at creep speed

• Count variation is very small (+/– 2%)• Total sliver length can be used for the direct process

17

Shorter processesIntegrating the drawframe into the card boostsprofitability and productivity. Rieter integratescomplete drawframe modules and can thusincorporate the proven technology and exten-sive know-how of the SB and RSB drawframes.The auto levelling process has also beenoptimized for the combined card/drawframesolution. It has become apparent that onlyoptimized system solutions are successful inindustrial-scale operations.

Integrated grinding of the card clothingThe incorporation of the Integrated GrindingSystem (IGS) means that the cylinder and flatsclothing is always sharp. This offers a numberof advantages:

• Improvement in sliver quality throughconsistently higher levels of nep and trashextraction

• A 30%–50% increase in the clothing’sservice life

• Reduced maintenance effort• Increased machine availability

The C 60 card is designed for the futurewith its technology and flexibility. It outperforms all other cards in meetingthe highest quality standards for finering-spun yarns as well as achieving thehighest production performance forrotor yarns in a single machine concept.

Literature references

[1] Müller J., Weidner-Bohnenberger S.,Stampfer A.: Rieter Rotor System. Special print, Rieter Machine Works Ltd.,Winterthur/Switzerland, 2003

[2] Gresser, G.: Eliminating foreign particlesand neps in the carding process.Dissertation, University of Stuttgart, 1998

Rieter Machine Works Ltd.Klosterstrasse 20CH-8406 WinterthurT +41 (0)52 208 71 71F +41 (0)52 208 72 83

Rieter IngolstadtSpinnereimaschinenbau AGFriedrich-Ebert-Strasse 84D-85055 IngolstadtT +49 (0)841 9536-01F +49 (0)841 9536-880

Rieter CZ a.s.Csl. armády 1181CZ-562 15 Ústí nad OrlicíT +420 465 557 389F +420 465 557 249

http://www.rieter.comE-mail: sales.sys@rieter.com

The data and illustrations in thisbrochure refer to the date of print-ing. Rieter reserves the right to makeany necessary changes at any timeand without special notice. Rietersystems and Rieter innovations areprotected by patents in most indus-trialized countries.

1768e-AKAE-5-Printed in Switzerland