Carding Booklet

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Table of contents

1. Introduction to cotton & fibres 2A. Cotton 2B. Synthetics 3C Other fibres 4

2. Introduction to carding 5Lickerin 5Cylinder – Back Fixed Flats 5Cylinder – Tops 5Cylinder – Front Fixed Flats 5Cylinder – Doffer 5

3. Product and service offering 7

4. Mounting and maintenance of card clothing 84.1 Introduction on maintenance 8

A Blowroom 8B Card 8

Quality based 8Volume based 8Microscopic 9Maintenance schedules for Duratech wires 10Maintenance schedules for Ultra wires 11

4.2 Mounting metallic wire 12Bare Cylinder and Doffer Grinding 12Cylinder and Doffer Wire Mounting 12

4.3 Tops clipping and mounting 134.4 Maintenance re-sharpening 15

Super cylinder wire 15Duratech and Ultra cylinder wire 15Tops 15A Tops re-sharpening in the card 15B Tops re-sharpening off the card 16Doffer wire 16

5. Fixed flats and fixed flats systems 17XLSA under Lickerin 17XLR & Pretech rear fixed flat systems 17XLX, XLXV, XLXE, XLXEV front fixed flats systems 17

6. Settings and troubleshooting 18Gauge settings 20Speed settings 21Symptom/Cause/Remedy 22Card clothing specifications and maintenance 29Notes 39

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1. Introduction to cotton & fibres

The two main fibre groups that are processed on shortstaple (or revolving flat) cards are as follows:

A. Cotton

B. Synthetics

A COTTON:Cotton is still by far the most important fibre carded onshort staple cards. Cotton is a natural fibre and exists ina range of varieties, differing in quality characteristics.The most commonly used fibre characteristics for cot-ton are as follows:

• Micronaire (a measure combining fibre finenessand maturity)

• Staple Length• Maturity

(indication of fibre wall thickness, see figure 1)• Strength• Grade • Trash Content

For carding, the above parameters are consideredtogether with card make and model and yarn producedwhen specifying card clothing.

Figure 1: Cross section of cotton fibres showing the inherentvariation in fibre maturity (fibre wall thickness)

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Although it is possible to range cotton in different ways, a way of distinguishing cotton according to range of character-istics important for carding is:

• Range for the maturity ratio> 1.00 : very mature0.95 – 1.00 : above average0.85 – 0.95 : mature0.80 – 0.85 : below average0.70 – 0.80 : immature

• Ranges for fibre strength (bundle strength in cN/tex)Below 21 : very weak21 – 24 : weak24 – 27 : medium27 - 30 : strongOver 30 : very strong

Fine, immature and weak cottons have to be cardedcarefully; otherwise, there is a risk to break fibres result-ing in more nep generation. Immature fibres do not onlyform neps easily, but do not absorb dyestuffs easily andwill dye to a lower shade, making immature nepsextremely visible in finished fabrics.Gentle carding can be achieved by reducing productionrates, reducing lickerin and cylinder speeds and via theuse of appropriate card clothing.

It is recommended to use less aggressive card clothing(lower front angle and/or lower point density) and lessaggressive speed settings in the case of delicate andweak cottons.

B SYNTHETICS:

A range of man-made fibres can be carded on short sta-ple cards. The most widely used are as follows:

• Viscose, lyocell and modal (all regenerated cel-lulosic fibres)

• Polyester• Acrylic.

Within each group, fibres exist in different lengths andfinenesses. Fineness is mostly expressed in dtex ordenier, length in mm. Carding of synthetic fibres ismostly done at lower speeds and more open settingsthan cotton carding. Card clothing also has to be adapt-ed to the fibre and the application.

• Range for micronaireBelow 3.0 : very fine3.0 to 4.0 : fine4.0 to 5.0 : medium5.0 to 6.0 : coarseOver 6.0 : very coarse

• fibre length range (staple length or UHML)< 25 mm : short25 – 28 mm : medium28 – 32 mm : medium to long32 – 36 mm : long> 36 mm : very long

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C OTHER FIBRES:Fibres such as linen, silk, wool, ramie and other special-ity fibres can also be processed, on their own, or inblends. For carding, the usual parameters are consid-ered together with card make and model and yarn pro-duced when specifying card clothing.

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2. Introduction to carding

Carding is the process of gradual opening and cleaningof fibre tufts and parallelising of the fibres.Before carding takes place the fibres need to be openedand cleaned in the blowroom. Lack of blowroom effi-ciency will also result in negative yarn results, e.g. inincreased Classimat faults, in decreased card perform-ance and in reduced lifetime of the clothing of the card.

Lickerin: The fibre tufts are presented by the feed roller and takenby the lickerin. The lickerin opens the fibre tufts, trashwill be removed by opening the tufts and via centrifugalforces. Carding segments (or lickerin fixed flats) help to furtherreduce tuft size.

Cylinder - Back Fixed Flats:The opened tufts are transferred from the lickerin to thecylinder. The fibres will pass the rear fixed flats. The graduallyincreased density of the different fixed flats at the backwill improve the efficiency of opening the fibres and pro-tect the revolving flats. Mote knives (and suction ele-ments) at the back remove trash and dust.The back of the card is responsible for tuft opening and

removal of coarser trash. A higher number of Classimatfaults can be a consequence if the back of the card is notworking properly.

Cylinder – Tops:The fine carding (fibre individualisation, nep removal,fine trash removal) is the task of the tops (revolvingflats). The tops setting to the cylinder is gradual: widerat the back, and closer at the front of the card for pro-gressive and efficient carding.The tops are where the main carding process takes place(nep reduction and fine trash removal).

Cylinder - Front Fixed Flats:Front fixed flats have a combing function, to reduce trail-ing hooks and “finish” the parallelisation process priorto stripping the cylinder at the doffer. The result is a

reduced number of imperfections (IPI) in the spun yarn.Mote knives between the front fixed flats allow elimina-tion of dust and trash at the front of the card.

Cylinder – Doffer:The doffer will collect fibres (depending on the transferrate) from the cylinder and deliver these to the strippingrollers after which the sliver is formed.Problems at the front or at the doffer can result in ahigher yarn imperfection index (IPI). The doffer affectsthe regularity (CV) of the card sliver.

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This information applies in general, as the process stepsfollowing the card will also affect yarn quality to a largeextent. Basic recommendations for good quality cardingare:

• The card clothing needs to be selected depend-ing on the specific card, on the fibres and on theend application (spinning process, qualityrequirements,…). Table 1 gives a basis for cardclothing selection.

• Settings of the cards. These are mostly recom-mended by the card manufacturer (OEM),together with the schedules for the verificationof the settings. The fibres, end application andproduction rate can affect the choice of card set-tings.

• Good maintenance schedules of the card cloth-ing are required: all card wire has to be sharpand in good condition. Proper maintenance ofthe blowroom is also required.

• Maintenance and cleaning of the card accordingto the guidelines of the card manufacturer

Cotton Man made fibres BlendsCotton/ Regenerated

OE yarn Carded combed < 1 dtex 1,5-3 dtex > 3 tex man made

Cylinder < 40kg/h C20-30-66 C20-30-86 C20-30-86 C25-20-63 C25-20-63 C25-20-63 C20-30-86 C25-25-72C20-35-86 C20-35-86 C20-35-86 C25-20-72 C25-20-72 C20-30-66

C20-30-95

> 40kg/h C20-35-86 C20-35-86 C20-30-86 C25-20-72 C25-20-63 C25-20-63 C20-30-86 C20-30-66C20-35-95 C20-35-95 C20-30-95 C25-30-72 C25-20-72 C25-35-86 C20-30-86C20-40-95 C20-40-95 C20-35-95 C25-30-86 C25-30-72

Doffer D40-30-30R2 D40-30-30R2 D40-30-30R2 D40-30-30R2 D40-30-30R2 D40-30-30R2 D40-30-30R2 D40-30-30R2D47-30-30R2 D47-30-30R2 D47-30-30R2 D47-30-30R2 D47-30-30R2 D47-30-30R2 D47-30-30R2 D47-30-30R2

Tops TL40 TL50 TL52 TL40 TL40 TL30 TL44 TL40TL44 TL52 TG52 TL44 TL44 TP27 TL50 TL44TG45 TG52 TG55 TG45 TG45 TG45 TG45

TG52

Stationary Flats Lickerin 57/65/88 57/65/88 57/65/88 57/65/88 57/65/88 57/65/88 57/65/88 57/65/88LT - DT - HT - ST XT - LTS2 - LTC2

Stationary Flats Rear 88/160/270 160/270/330 270/330/440 88/160/270 88/160/270 88/160 160/270 88/160CT - ST - XT

Stationary Flats Front 330/440/550 550/660 550/660 4440/550 330/440 270/330 440/550 440/550CT - ST - XT

Table 1: Specifications for card clothing for a range of applications

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3. Product and service offering Bekaert Carding Solutions offers card clothing for blow-rooms and for cards of virtually all makes and modelsand for all applications. Metallic wires are available indifferent steel grades, differing in wear resistance andlifetime.

We offer our services in specifying card clothing for par-ticular applications, as well as in providing maintenanceschedules for optimum quality performance.

Our regional workshops located around the world willperform mounting and maintenance services of thehighest quality to enable spinners to get the best qualityresults.

We are happy to support and inform customers doingcard clothing servicing themselves about the best waysto service card clothing.

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4. Mounting and maintenance of card clothing

4.1 Introduction on maintenance

A Blowroom:• Maintaining the blowroom in good condition will

result in better pre-opened cotton, with lowertrash content and less neps, fed into the card.

• The consequence is a better carding result(lower number of neps and less trash in the cardsliver) as well as a longer lifetime of the cardclothing.

• Therefore, it is recommended to replace blow-room wires every 2000 to 2500 tons.

• Lickerin wire and fixed flats cannot be re-sharp-ened and are recommended to be changed indue time for carding performance and to protectcylinder and tops from accelerated wear.

• Cylinder and tops have to be re-sharpened inorder to counter their normal wear.

The essential rule in maintaining card clothing is to takeaction in time.

It is advised to re-sharpen the tops and cylinder beforethe teeth become excessively worn. It is preferred to re-sharpen lightly and regularly, rather than to wait till wearis excessive, as a heavy grind would be required to cor-rect the worn teeth of the wire. If the wear is excessive,re-sharpening will not be able to rectify the worn teeth.

We encounter different ways of maintenance schedulesin spinning mills:

Quality based:Quality of sliver is measured (mostly neps viaAFIS testing) and corrective maintenance is per-formed when acceptable quality levels are nolonger obtained. Figure 2 shows the principle ofa neps based maintenance schedule.

Volume based: the maintenance periods are defined accordingto throughput volumes. Tables 2 and 3 showtypical maintenance schedules for cardsequipped with respectively Bekaert Duratechand Ultra card clothing.

B Card:• Draw frame blending of slivers from different

cards is the correct practice for good qualityspinning.

• Therefore, we strongly discourage the mainte-nance of card clothing of several cards at thesame time.

• When the maintenance intervals of the differentcards are spread out evenly throughout the life-time of the wire, the sliver blending at thedrawframe will ensure a constant yarn quality.

• The essential goal of the maintenance is tomaintain the quality of the lickerin, fixed flats,cylinder, doffer and tops: keeping the wiressharp.

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Microscopic: Evaluation of card clothing with a portablemicroscope (minimum magnification 30) todetect the first signs of wear after which appro-priate light re-sharpening can be performed

In reality, a combination of any of the above three meth-ods can be used to determine when card clothingreplacement or re-sharpening is required.

A number of parameters will affect the wear rate and life-time of card clothing. Raw material has an importanteffect.

• Cotton blends containing a high level of trash(especially if sand is present) will wear the wirepoints more quickly than clean cottons.

• Dull or matt man-made fibres containing a highamount of delustrant (mostly titanium dioxide)will cause more rapid wear. - Some dyestuffs used in synthetic fibres are

very aggressive against card clothing.

Maintenance requirements also depend on the qualityacceptance requirements of the mill and on the propersettings and general maintenance of the card.Upon request, BEKAERT Carding Solutions can providespecific maintenance schedules according to card cloth-ing and application.

Quality (e.g. neps)

Acceptance limit

Processed volume

re-sharpening

1st 2nd 3rd

Figure 2: Example of maintenance schedulefor cylinder and topsbased on sliver quality.

Sche

dule

1

Sche

dule

2

Sche

dule

3

Sche

dule

4

Feed

Rol

ler

Card

ing

Segm

ents

Lick

erin

Back

Stat

iona

ry F

lats

Revo

lving

flats

Main

Cyli

nder

Flat

Clea

ning

rolle

r

Flat

Clea

ning

Stri

p

Fron

t Stat

iona

ry F

lats

Doffe

r

Doffe

r Clea

ning

Rol

ler

Doffe

r Stri

ppin

g Ro

ller

2000 T 2000 T 2000 T 2000 T

600 T 700 T 900 T 1000 T

515 T 600 T 780 T 860 T

410 T 480 T 615 T 680 T

290 T 340 T 435 T 485 T

160 T 185 T 236 T 260 T

Cylinder wire: Duratech Lickerin: Duratech = replacement = resharpeningMaterial Throughput

CARD CLOTHING - MAINTENANCE SCHEDULES FOR DURATECH WIRES

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1) The selection of the maintenance schedule depends on:• raw material used (e.g. amount and type of trash)• yarns spun• quality requirements of the spinning mill

2) According to quality demands, the recommended guide values may deviate to high-er or lower levels.

3) According to raw materials, the recommended guide values may deviate to higher orlower levels.

4) The main cylinder intervals recommend the use of a traversing stone resharpeningmechanism.

5) Feed rollers if wired change every 2000 ton, otherwise when damaged.6) For cards with brush doffer stripping mechanism, change when damaged.7) An alternative method of controlling quality is by nep test data to resharpen and

replace wire in due time.

Table 2:Volume based maintenanceschedules for BekaertDuratech card clothing

Sche

dule

1

Sche

dule

2

Sche

dule

3

Sche

dule

4

Feed

Rol

ler

Card

ing

Segm

ents

Lick

erin

Flat

Clea

ning

Rol

ler

Flat

Clea

ning

Rol

ler

Back

Stat

iona

ry F

lats

Revo

lving

Flat

Main

Cyli

nder

Fron

t Stat

iona

ry F

lats

Doffe

r

Doffe

r Clea

ning

Rol

ler

Doffe

r Stri

ppin

g Ro

ller

2000 T 2000 T 2000 T 2000 T

700 T 800 T 1000 T 1200 T

600 T 690 T 860 T 1040 T

480 T 550 T 685 T 820 T

340 T 390 T 485 T 580 T

185 T 240 T 260 T 315 T

Cylinder wire: Ultra Li wire: Ultra = replacement = resharpening Material Throughput

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CARD CLOTHING - MAINTENANCE SCHEDULES FOR ULTRA WIRES

1) The selection of the maintenance schedule depends on:• raw material used (e.g. amount and type of trash)• yarns spun• quality requirements of the spinning mill

2) According to quality demands, the recommended guide values may deviate to high-er or lower levels.

3) According to raw materials, the recommended guide values may deviate to higher orlower levels.

4) The main cylinder intervals recommend the use of a traversing stone resharpeningmechanism.

5) Feed rollers if wired change every 2000 ton, otherwise when damaged.6) For cards with brush doffer stripping mechanism, change when damaged.7) An alternative method of controlling quality is by nep test data to resharpen and

replace wire in due time.

Table 3: Volume based maintenanceschedules for Bekaert Ultracard clothing

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4.2 Mounting metallic wire

Bare Cylinder and Doffer Grinding:• With old cards, it is required to verify the con-

centricity of the surfaces prior to mounting wire. • With more modern cards, this is only required in

case there has been a crash. • The maximum acceptable tolerance for level-

ness (concentricity and lateral straightness)over the entire surface of the bare cylinder anddoffer is 0.02 mm for modern high productioncards; and 0.04 mm for older cards.

• In case the concentricity is outside tolerance,the concentricity has to be restored via a suit-able bare cylinder grinder. In case it is requiredto grind the bare cylinder, new border wireneeds to be applied.

Cylinder and Doffer Wire Mounting:• The mounting method must be in accordance

with the instructions of the mounting equipmentsupplier.

• The most important aspect of mounting the wireis in applying the minimum tension, but suffi-cient to ensure that the wire sits firmly on thecylinder surface.

• Excessive tension increases the risk of crackingand breaking the wire during mounting.

• On older cards, the cylinder or doffer surfacecan yield slightly in case of excessive mountingtension, resulting in an uneven surface of thewired cylinder.

• Insufficient tension and lack of form (bending ofthe wire) results in the wire falling over andbeing incorrectly mounted.

• The general rule is to apply at maximum the ten-

sion in kg that corresponds to the rib thicknessin mm, multiplied by 10. For instance, with a 0.5mm rib wire, the maximum acceptable tension is5 kg. Best practice is to use 2 to 3 kg mountingtension for 0.5 mm rib cylinder wire.

• The surfaces must be kept free of dust and dirtduring wire mounting.

• Ensure that the cylinder and doffer wire areapplied as smoothly as possible in order toavoid high spots over the working surface.

• Today’s precise cylinders have very fine points.Thanks to the high quality and height uniformityof metallic wires of BEKAERT Carding Solutions,it is not required (nor advised) to re-sharpen thewires after installation before starting the card.

• However, to check for any errors caused inmounting the wire, first check the doffer tocylinder setting. If unacceptable high spots are

found on the doffer (although wire mountinghas been done carefully) these should beremoved using minimal pressure and the light-est possible cut with a well-maintained re-sharpener or hand stone. A too high pressurecould result in hooked doffer teeth, negative forthe performance of the doffing action.

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BEKAERT’s UNIMECH 2000 system of wire mountingequipment (see figure 3) includes a smooth variable DCdrive unit and a mounting arm and support system,designed specifically to achieve regular and smoothmounting of metallic wire. It has a tension gauge thatallows accurate setting and control of the winding ten-sion.

4.3 Tops clipping and mounting

• BEKAERT tops are manufactured to accurate tol-erances (for carding performance), sharp tips(for carding efficiency) and high hardness andhardness depth (for lifetime of the tops).

• When mounting the tops on the card, the heightuniformity and sharpness need still to be pres-ent.

• The process of preparing the flat bars, clippingthe tops and grinding (if required) has to bedone very carefully by skilled operators usingthe proper equipment.

• A good top can be ruined if the mounting and re-sharpening process has not been done properly.

The whole process of tops clipping and mounting con-tains several steps:

1. Stripping the worn tops from the flat bars2. Cleaning the flats to remove any dirt3. Verification of flat ends and flat end milling (if

required)The bare flats are checked to ensure that theyhave the correct and accurate bevel on the seat-ings. If the bevel is not correct, or if the seatingsare worn, the end seatings have to be milled ona flat end-milling machine. Flat end milling isperformed to make the seating of all the flat barsaccurate before clipping. End milling is not pos-sible on all types of flats.

4. Verification and correction of height uniformityHeight uniformity is measured on a flat test bedusing a dial gauge. Irregularities along the faceof the flat will be reproduced to the points of thetops after clipping. Therefore, it is recommendedto make the flats as level and as uniform in

Figure 3: Unimech 2000 wire mounting equipment

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height as possible prior to clipping the tops. Theend milling process is improving height unifor-mity between flats. Height differences withineach flat can be corrected via manually manipu-lating the flats to straighten and level them. It ispossible to insert paper strips between the topsand the flats during the clipping process to cor-rect inaccuracies. Complete level plastificationof the face of the flat bars is an alternative.

5. Clipping the tops on the flats6. Height uniformity control on a flat test bed using

a dial gauge:Measurement of the height uniformity of thetops on the heel portion of the clipped tops only(step 6, see figure 4) is recommended. Each topwill be mounted on the card under an angle ofabout 1° (the exact angle depends on the card),which means that only the heel portion really

matters for setting the tops to the cylinder.7. Grinding

If there is height variation outside tolerance afterclipping, the tops can be ground on a flat grind-ing machine. Due to the tapered setting of eachindividual top on the card, it is sufficient to onlyheel grind over 3 mm of the surface of the flat(see figure 5). If proper care has been taken inthe preparation of the flat bars a slight heelgrinding (re-sharpening) will be sufficient toachieve the required height tolerance. Excessivegrinding would reduce the lifetime of the tops aswell as the carding performance.

8. BurnishingIf heel grinding has been done then burnishingis also required to polish the wire and to elimi-nate small hooks caused during the grinding.

It can be concluded that for good carding performanceand long lifetime of tops the requirements are:

• The tops need to have sharp points with highhardness for high nep removal efficiency andlong lifetime.

• The accuracy of the whole flat set must be to theabsolute minimum after clipping so that theycan be set as close to the cylinder as possible.

The skills of the operator in the tops clipping and mount-ing process are crucial to achieve these main factors.

Please contact BEKAERT for detailed information aboutclipping and mounting flat tops to achieve the best per-formance and lifetime.

Figure 4: Principle of heightmeasurement on the heel only

1° 1°

Height measurement on heelonly with fixed dial gauge

2 to 3 mm heel grinding

TOPS GRINDINGTOPS HEIGHT

MEASUREMENT

Figure 5: Tops grinding –heel grinding only

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4.4 Maintenance re-sharpening

Super cylinder wire:Super cylinder wire can be re-sharpened using a rotaryconventional re-sharpening device only under strictlycontrolled procedures. The re-sharpener should be setto ensure the highest degree of parallelism with thecylinder. The re-sharpening should be as light as possi-ble with a minimum of spark. The danger is that if the re-sharpener is set to increase spark, the result is damageof the wire, reduced carding quality and dramaticallyreduced lifetime.

Duratech and Ultra cylinder wire:It is recommended to only use modern, well maintainedtraversing stone re-sharpening equipment, used as indi-cated in the guidelines of the equipment. A visual assessment under a microscope (minimum

New wire Maximum allowed wear priorto re-sharpening

Good re-sharpened wire Badly re-sharpened wire with burrs

Figure 6: Evaluation of re-sharpening of cylinder wire

magnification 30) is recommended to evaluate the re-sharpening (see figure 6).

Tops:A) Tops re-sharpening in the card:It is recommended to use a well maintained full-widthemery re-sharpener in the card. The tips of the topsshould be precisely reground over the whole surface.Care should be taken that the re-sharpening roll is setparallel with the tops for equal re-sharpening over thefull width. During re-sharpening, the spark should beeven over the full width of the card. If not, setting of there-sharpening roller to the tops needs to be adjusted. The required level of grinding is to create a sharp lead-ing edge. If the level of re-sharpening is not enough tocreate a sharp leading edge, initial nep results after re-sharpening will be good, but the amount of neps willraise very fast again. Excessive re-sharpening results inloss of lifetime of the tops as too much material is takenaway. Care should be taken not to create a leading burron the teeth of the tops. This could happen when pres-

Figure 7: Tips of tops and re-sharpening

New pointWorn pointAfter grinding

Point of new tooth Point that needs re-sharpened

After correct grinding

Incorrect grindingcausing burrs

sure is too high. Evaluation of the tops can be done witha portable microscope (minimum magnification 30), see figure 7.

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B) Tops re-sharpening off the card:If a spinning mill has no access to a good quality fullwidth tops re-sharpener, the tops can be taken off andre-sharpened on a tops re-sharpening bed.

Doffer wire:The doffer should not be re-sharpened unless there is aproblem in controlling the web. Sometimes, particularlywith abrasive man-made fibres, the doffer wire canbecome polished to the extent that the fibres slip off. Theweb pre-doffs and goes out of control, with consequentreduction in carding efficiency. Re-sharpening the dofferwire will cure this problem. In any case, the doffershould be ground only slightly, otherwise the long deli-cate teeth needed for the doffing action will becomehooked and hence unable to release the web to the strip-ping system. It is recommended to use a striated dofferthat grips the fibre onto the wire.

For all re-sharpening operations, we recommend tocarefully follow the guidelines of the card manufacturerand of the re-sharpening equipment that is used.

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5. Fixed flats and fixed flats systems

Post-cardingfixed flats

Extended pre-cardingfixed flats

Trash extraction system

Pre-carding fixed flats system

Under licker-in fixed flats system

Trash extractionsystem

Figure 8: Card with fixed flatsystems under the

lickerin, at therear and at the

front of the card

Most modern cards are equipped with fixed flatsbeneath the lickerin, at the back plate region and in placeof the front stripping door. Fixed flat upgrade systems(see figure 8) can be installed on older carding machinesto improve the performance. BEKAERT provides suitablestationary flats systems to upgrade a large range ofcards.

XLSA under Lickerin:It combines a minimum loss of good fibres in the lick-erin waste with intensive pre-opening and cleaning ofthe fibre tufts.

XLR & Pretech rear fixed flat systems:Give extra gentle opening and pre-carding of the fibretufts coming from the lickerin. A well opened fibre massis presented to the tops (revolving flats) for the finecarding action. The rear fixed flats act as trash barrier toprotect the revolving flats and increases the lifetime ofthe tops.

XLX, XLXV, XLXE, XLXEV front fixed flats systems:They reduce neps and yarn imperfections. Combinedwith a knife and extraction system (Ventech), trash andmicro-dust are removed prior to the doffer action.

The replacement fixed flats are available in differenttooth densities to suit the widest range of applications.The exchange of fixed flats is easy to carry out.

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6. Settings and troubleshooting

The settings of the card will have an effect on the prop-erties of the card sliver and of the final yarn. In the firstplace, it is recommended to follow the setting instruc-tions provided by the manufacturer of the card. Table 4lists card settings guidelines for a modern high speedcard running at moderate production rates (indicatedsettings are in warm condition of the card). The settings of the card will have an effect on the prop-erties of the card sliver and of the final yarn. In the firstplace, it is recommended to follow the setting instruc-tions provided by the manufacturer of the card. Table 4can be used as a first guideline for settings for modernhigh speed cards running at moderate production rates.After mounting new tops the card is run with the revolv-ing flats in more open setting (0.35 mm or 14 thou) dur-ing 15 tonnes. This allows the tops “to set” on the card.The tops settings are then brought down.

Setting Cotton Synthetics

in mm in thou in mm in thou

Feed plate to lickerin 0,375 15 0,45 18

Knife to lickerin 0,5 20 0,5 20

Carding segment to lickerin 0,45 18 0,45 18

Lickerin to cylinder 0,25 10 0,25 10

Rear stationary flats to cylinder (tapered setting) 0,45 to 0,30 18 to 20 0,45 to 0,30 18 to 20

Mote knife rear to cylinder 0,3 12 0,3 12

Tops to cylinder - entrance 0,25 10 0,3 12

Tops to cylinder - exit 0,2 8 0,25 10

Front stationary flats (tapered setting) 0,25 to 0,20 10 to 8 0,25 to 0,20 10 to 8

Mote knife front to cylinder 0,3 12 0,3 12

Doffer to cylinder 0,15 6 0,15 6

Stripper to doffer 0,15 6 0,15 6

Table 4: Card settings guideline for a modern high speed card running at moderate production rates(Indicated settings are in warm condition of the card)

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Gauge and speed settingsTable 5 (page 20)Table 5 gives an overview of the effects settings have onthe quality and properties of sliver and yarn. The tablecan offer help to optimise carding for particular purpos-es and in trouble shooting. Most of the settings have anoptimum value. The optimum can depend on the qualitylevel that is looked for. (Optimum) Settings will dependon the card model, as well as on the fibres processed,on the end application and on quality requirements.Table 5 gives insight in the effects of settings and is aguideline in troubleshooting and in optimising the cardperformance. The table contains information that is validfor a broad range of cards, older as well as newer cards.

Sometimes, problems can occur during carding. Thetechnician will have to analyse the problem, its causesand take the appropriate action. First source for informa-tion on troubleshooting is the card manual provided bythe manufacturer (OEM). Furthermore, the table includ-ed in this booklet that indicates the effect of card set-tings on carding can already be a help.

Troubleshooting table for cardingTable 6 (page 22)A further help is the SCRA table (Symptom – Cause –Remedy & Action). For a range of problems (symptoms)you find possible causes and how to correct on the card.The SCRA table is not card specific, it contains trou-bleshooting information for old as well as for morerecent cards.

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Lap guide (lap feed cards)

Feed roller to plate

Feed plate to lickerin

Mote knife to lickerin

Lickerin to cylinder

Cylinder to lower back sheet

Positioning of the lap

Firm holding of fibre material

Opening

Amount of droppings

Fiber transfer

Moving fibres from lickerin onto cylinder

Web is widened when widened. When narrowed, both sides ofthe web become thicker.

If widened, fibre tufts are more loose, easy slipping out. If toonarrow setting, feed roller and plate can come into contact andget broken.

Too wide: insufficient opening and increase in fibre waste. Iftoo narrow, fibres get damaged and the transfer of the fibres tothe lickerin becomes difficult

Closer setting to lickerin: more droppings (fibre + waste); moreopen setting: less droppings removed.

If too wide, fibres can remain on the lickerin. It too narrow, fearof wire contact between lickerin and cylinder; and broken fibres

When widened, fibres are liable to remain on the lickerin, napfly increases and web unevenness can occur. If too narrow,fear of wire contacts.

Cylinder to upper back sheet

Cylinder to tops

Cylinder to upper front sheet

Cylinder to bottom sheet

Cylinder to doffer

Cylinder to cylinder casing (doffer side)

Cylinder to center of undercasing

Lifting of fibres off cylinder and adjustment of fibre fly

Carding

Adjustment of flat strip

Improvement of fiber separation from the cylinder and transferratio to the doffer

Transfer of fibres

Adjustment of air flow

Adjustment of falls (good fibres) under the cylinder

Widened setting: lifting of fibres from the cylinder is intensi-fied, possibly touching the top. If narrowed, lifting of fibres isreduced, possibly touching the cylinder.

Wider setting: reduced carding, neps increase and flat stripdecreases. Narrower setting: flat strips increase, fear of wirecontact, fibres are easily damaged. If the setting is not taperedback to front, high number of broken fibres and reduced lifeti-me of tops.

Wider setting: the amount of flat strip increases. Narrower set-ting: decrease of amount of flat strip

The transfer ratio decreases if set wider and cotton can blowout at doffer. Too narrow setting, the web can become unevenand risk of wire contact.

Too wide setting decreases the transfer ratio, neps are easilyformed. Too narrow setting: web becomes poor, fear of wirecontact (wire damage), and fly can increase.

The air flow is disturbed if the clearance is too wide or too nar-row, resulting in poor quality of web and sliver.

Wider setting: the amount of droppings decreases.

Adjust Action Effect

Gauge settingsTable 5: Effect of setting modifications on carding results

2121

Cylinder and undercasing, at lickerin side

Top card clothing and topscleaning system

Adjustment of falls (good fibres) under the cylinder

Separation of flat strip

If widened, the amount of droppings beneath the cylinder dec-reases, the amount of dropping beneath the lickerin increases

If widened excessively, flat strip cannot be separated and thetops load. If setting is too close, there is risk of wire contact.

Card production rate

Cylinder speed

Lickerin speed

Speed of revolving tops

Production in kg/h

Carding intensity

Fiber opening

Movement of tops over the cylinder

Is having a tremendous effect on nep removal efficiency. Thehigher the card output, the lower the nep removal efficiency.Effect on sliver CV and on yarn imperfections is less pronoun-ced. A too high production rate will have a negative effect onthese parameters as well. Longer and/or weaker fibres aremore vulnerable when increasing production rates.

Higher cylinder speeds result in lower trash in sliver, more flatstrip and better carding (higher NRE). Danger with too highcylinder speed is fibre breakage (SFC increases) and increasein yarn IPI.

Higher lickerin speeds protect the lifetime of cylinder and tops.Faster rotation of lickerin results in less neps, less trash andlower IPI. Excessive lickerin speeds are negative becausefibres get broken (higher yarn IPI, more neps). Immature andweak cottons are especially vulnerable at higher lickerinspeeds.

Increase of speed of the revolving tops increases NRE, flatstrip increases.

Adjust Action Effect

Speed settingsAdjust Action Effect

Gauge settings

22

Table 6: Troubleshooting table for carding

Excessive blow-out at cylinderends




Broken or malformed selvedges


Card feed too wide

Incorrectly set underscreen

Card cylinder plates are incorrectly set, particularly the lowerfront plate

Dull cylinder wire

Leakage of oil or grease from bearings

Rough or broken underscreens

Ensure that the lap width is not too wide (see instructions cardmanufacturer)

See setting chart for correct settings and adjust

Verify and adjust settings according to the instructions of thecard manufacturer

Resharpen cylinder wire; or replace if damaged or if excessivewear

Perform proper maintenance of bearings

Repair or replace

Symptom Cause Remedy/Action

Fibre blow-out at web selvedges

Lickerin underscreen is remo-ving too many good fibres

Lickerin underscreen set too wide from the lickerin roller Adjust settings (lickerin underscreen, mote knife)

Fibres in lickerin trash

Lickerin underscreen is remo-ving too many good fibres

Lickerin underscreen is notremoving enough trash

Lickerin underscreen is notremoving enough trash

Accumulation of short fibresbetween the mote knife and thelickerin underscreen

Dull or incorrect type of lickerin wire

The lickerin underscreen is set too close to the lickerin roller

The feed plate is set too far from the lickerin roller

Incorrect mote knife setting

Replace wire

Correct settings

Correct settings

Verify and correct the settings of the mote knife according tothe setting instructions of the card manufacturer

Flat strips too heavy




Front plate top edge setting to cylinder is too wide

Cylinder back plate set too wide

Overloaded cylinder

Lickerin screen too close to lickerin

Adjust settings according to the recommendations of the cardmanufacturer


See at “Cylinder loading”

Make a wider setting

Flat strips

23





Flat waste thickness is not uni-form



Many long fibres in the flat strip



Many leaf wastes in the flat strip

Too narrow setting of the cylinder to the tops

Gauge of bottom sheet too narrow

Wear of cylinder wires

Damage of tops card clothing

Defective fitting of top sheet

Misalignment of gauge tops to cylinder

Defective fitting or misalignment of bottom sheet

Clearance between feed plate and lickerin is too wide

Tops to cylinder set too wide

Rotation of lickerin is too slow

Rotation of lickerin is too slow

Adjust settings cylinder to tops according to recommendationsof the card manufacturer

Adjust setting

Sharpen or replace cylinder wire

Sharpen or replace tops

Adjust fitting and correct settings

Adjust settings cylinder to tops according to recommendationscard manufacturer

Adjust fitting of the bottom sheet

Adjust setting between feed plate and lickerin

Adjust settings tops to cylinder, closer setting

Increase speed of lickerin

Increase speed of lickerin


Many leaf wastes in the flat strip

Fluctuation in the amount of flatstrip

Fluctuation in the amount of flatstrip

Insufficient trash extraction in the lickerin area (in this case,damage of tops is also frequent)

Improper motion of the top card clothing (belt slipping, elon-gation of flat chain, difference in drive left and right)

Contact between tops and cylinder wire

Verify and adjust lickerin area: lickerin wire status, settings, lic-kerin speed, mote knife condition and settings

Verify and adjust/ repair the motion of the tops

Adjust settings, sharpen wire

Lickerin snatchesLickerin snatches

Lickerin snatches

Lickerin snatches

Lickerin snatches

Lickerin snatches

Lickerin snatches

Lickerin snatches

Worn feed roller bearings

Worn feed roller shafts

Bent side shaft (if applicable)

Inefficient weighting system on feed roller

Eccentricity in feed roll

Bowed feed plate

Feed roller to the feed plate setting is too wide

Replace bearings

Replace shafts

Replace side shaft

Analyse operation of the weighting system and repair/ replaceaccordingly

Correct / replace

Correct / replace


Flat strips

24


Cylinder loading

Cylinder loading

Cylinder loading

Cylinder loading

Cylinder loading

Cylinder loading

Cylinder loading

Doffer set too far from the cylinder, consequence can be cylin-der loading and/or higher neps

Accumulations of trash and seed particles

Local damage of the cylinder wire, e.g. flattened, rubbed, bentor hooked wire will all interfere with the correct flow of the fibrethrough the card. Fibres may be retained and bands may formaround the damaged part of the cylinder

Flat settings too close, especially in case of cotton with a rela-tively high trash content and if the tops have a dense populati-on

Contaminated stock

Back plate too close to cylinder

Lap feed: double thickness fed at the selvedges resulting inbanding on the cylinder and neps in the web

Set doffer as close as possible to cylinder. See recommendati-ons of the card manufacturer

Clean the cylinder regularly, depending on the type of cotton.Adjust the raw material reducing the amount of waste. Checkthe blowroom for efficiency, replace the blowroom wire if dull.

Replace cylinder wire. For slow speed cards, local repair ofwire could be possible but should be done with the greatestcare only and is not free of risk.

Widen the settings of the tops

Check opening and stock laydown for contamination. Verifyblowroom effciency and replace blowroom wire if dull.

Adjust plate setting

Check the lap feed. The width of the lap should be narrowerthan the width of the card

Lickerin loading

Lickerin loading

Doffer loading

Doffer loading

Lickerin loading

Lickerin loading

Contaminated stock

Lickerin wire not suited for type of raw material being run

Damaged wire or wire with burrs

Take-off (stripping) improperly set

Damaged lickerin wire

Lickerin setting to cylinder too wide

Check opening and stock laydown for contamination. Verifyblowroom effciency and replace blowroom wire if dull.

Consult manufacturer

Grind, brush or recloth depending upon the degree of damage

Adjust take-off (stripper) settings

Replace lickerin

Adjust setting lickerin to cylinder

Loading on wired rollers

Nep count

High nep count

High nep count

High nep count

High nep count

Incorrect settings: doffer to cylinder, stationary flats, cylinderto flexible tops, or feed region, plates or screens

Dull cylinder or doffer wire

Dull or damaged flat tops

Dull or damaged lickerin wire

Verify all card settings

Clean, resharpen or burnish as required. The sharpness of thedoffer wire is as important as the sharpness of the cylinderwire

Resharpen or replace

Replace the lickerin wire

25

High nep count

High nep count

High nep count

High nep count

High nep count

High nep count

Fibres are retained in the form of bands (rings) on the lickerin.Such loadings will lead to strips of neps in the web.

Relative humidity is too high

Foreign matter, such as broken seeds are adhering to the wires

Dirty wire surface (especially the cylinder)

Loaded cylinder

Tops loading

Rewire lickerin

Relative humidity for cotton 45-55% (temperature 21-27 °C),for synthetics 55-65% relative humidity, temperature 25-30 °C

Brush the wires with a soft hand brush

Brush the wires with a soft hand brush

Clean the cylinder and check/correct all settings + see“Cylinder loading”

See “Tops loading” for Causes and Remedy/ Actions


Disappearing web/ high numberof sliver breaks


Underscreen set too far from cylinder

Dull or damaged doffer wire. If condition of the doffer wire isnot good, the transfer of fibres from the cylinder will not be

Set according to setting instruction of the card manufacturer

Clean, resharpen or replace wire

Sliver or web problems


Losing fibre off the doffer to themain cylinder

Losing fibre off the doffer to themain cylinder

Cloudy web

Cloudy web

Cloudy web

Cloudy web

Cloudy web

Holes in the web

good, which can also result in an increased number of neps.

Too wide setting stripping roller to doffer

Nose of front screen set too close to cylinder

Dull doffer wire

Lickerin undercasing set too far from lickerin

Feed plate set too far from lickerin

Damaged or dull lickerin

Unequal distribution of flat strips. Incorrect settings or sharp-ness of flat tops

Bottom edge of cylinder back plate set too wide

Interference with lay of fibres on doffer due to flocking on dof-fer end screen

Correct setting of the stripping roller to the doffer

Adjust settings

Grind doffer or replace as needed

Correct settings according to recommendations of the cardmanufacturer


Replace lickerin wire

Verify/ correct setting of flat tops. Resharpen flat tops if no lon-ger sharp or replace flat tops


Verify and adjust doffer screen

Nep count

26

Holes in the web

Holes in the web

Web sticking to crushing rollers







Flocking on frame side between doffer and cylinder

Damage to doffer wire. Draft will magnify even small holes ordents of the web on the doffer

Worn or damaged scraper blades

Insufficient tension on scraper blade springs

Insufficient draft between crushing rollers and calender

Crushing roller (calendar roller) pressure is too high

Relative humidity is too high or too low

Too many cotton seed particles

Honeydew in the web

Verify and adjust doffer and/or cylinder screen settings

Replace doffer wire

Do maintenance as per guidelines of card manufacturer

Increase tension

Draft between crushing roller and the calendar rollers shouldbe the highest that material can accept

Lower the pressure accordingly

Relative humidity for cotton 45-55% (temperature 21-27 °C),for synthetics 55-65% relative humidity, temperature 25-30 °C

Clean the edge of scraper blades frequently with solvent.Reduce relative humidity. Take measures to reduce trash

Reduce temperature, clean the crushing rollers frequently.Change the bale laydown: reduce the number of contaminatedbales.




Accumulation of fibre betweencard framing and underscreen;or accumulation of fibre aroundcylinder and doffer co-operationarea.

Accumulation of fibre betweencard framing and underscreen;or accumulation of fibre aroundcylinder and doffer co-operationarea.

Sliver variation

Sliver variation

Sliver variation

Sliver variation

Sliver variation

Lap too wide

Feed guides are incorrectly set

Framework of the card is greasy or dirty

Card underscreens (cylinder or doffer) are not correctly set tocontrol the amount of fibre being blown out at the periphery ofthe cylinder

Irregular feed

Eccentric feed roller

Incorrect meshing of gears

Tooth missing of one of the gears

Bottom edge of cylinder back plate set too wide

Check the lap feed. The width of the lap should be narrowerthan the width of the card

Verify and adjust the settings of the feed guides

Clean framework. Verify for the origin of the grease or dirt andcorrect

Verify and adjust card underscreen settings

Verify the feed and correct accordingly

Correct/replace

Correct gears

Replace defective gear



27

Sliver variation

Sliver variation

Sliver variation

Sliver variation

Sliver variation

Sliver variation

Banding on redirecting (strip-ping) rolls

Banding on redirecting (strip-ping) rolls

Web falling off stripping roller

Eccentric doffer

Eccentric doffing rolls

Eccentric calender rolls

Loose components

Excessive draft between calender rolls and coiler head; orincorrect tension

Dirty stripping roller underscreen

Bent or damaged wire

Dirt or oil patch on the wires

Incorrect setting between stripping roller and doffer

Detect source of eccentricity and correct



Fix components

Reduce draft and/or adjust tension

Clean stripping roller underscreen

Replace the stripping wire

Clean the wire, if required with an appropriate solvent

Adjust setting according to guidelines of the card manufactu-rer


Tops loading

Tops loading (= flat strip remai-ning in the tops)





amaged tops clothing

Tops set too close to the cylinder

Contamination, oil, grease, water or other foreign substance;rough top wire sides

Inaccurate brush settings (gauge)

Wear of the circular brush

Grind, brush or replace clothing as required

Adjust tops settings

Clean tops. Remove contamination from the raw material ifpresent

Adjust settings

Replace brush

TrashTrash in sliver

Trash in sliver

Trash in sliver

Trash in sliver

Low air suction

Choke under lickerin

Incorrect settings (gauges and speeds)

Insufficient trash extraction at the lickerin

Correct central air suction

Clean out choke. Make sure there are no chokes in the pipingand that the central air suction is correct before starting thecard.

Check all settings and adjust when necessary

Modify/ Adjust lickerin setting; increase lickerin speed; check/replace mote knives if required


Yarn strength

28

Trash in sliver

Trash and/or neps in sliver











Dull or damaged lickerin wire

Wear of tops

Wear of the cylnder wire

Too small amount of flat strip

Uneven gauge between tops and cylinder

Tops set too wide from the cylinder

Uneven or incorrect fitting back or front sheet

Wear of underlickerin knife(s), or of knives in the fixed flat sys-tems

Underlickerin knife(s) are not correctly set

Setting of the wings (under the lickerin) are too narrow

Stationary flat knife(s) are not correctly set

Stationary flats are worn, dull wires

Replace lickerin

Sharpen tops or replace

Sharpen cylinder wire or replace

Adjust settings tops

Adjust settings tops

Reduce setting tops to cylinder

Adjust back and/or front sheet and settings

Change the worn knive(s)

Set the underlickerin knive(s)

Open the wings

Check the settings of the knives ( at lickerin, back and front sta-tionary flats) and adjust if necessary

Replace stationary flats


Loss in yarn strength






Crush roller pressure is too high

Excessive lickerin speed

Incorrect type of lickerin wire

Insufficient flat strip

Insufficient trash and waste removed at lickerin

Feed plate to lickerin setting too close resulting in broken fibres

Reduce the pressure according to the guidelines of the cardmanufacturer

Reduce lickerin speed

Replace lickerin wire with appropriate type of wire dependingon fibre characteristics

Verify settings tops to cylinders, verify screen setting. Adjustsettings. Increase speed of revolving flats.

Verify all settings in the lickerin area and adjust to increasetrash removal

Increase the setting of the feed plate to the lickerin accordingto the fibre length and the recommendations of the card manu-facturer

Trash

29

Card clothing specifications and maintenance

Card make and model:

Production rate (kg/h):

Yarn count:

Fibres:

Sliver count:

1. Feed roller

Clothing specificationCard number: Maintenance information

2. Lickerin (single or triple lickerin cards)

3. Carding segments (lickerin)

4. Fixed flats rear

5. Cylinder

6. Revolving flats (tops)

7. Flat cleaning rollers


9. Front stationary flats

10. Doffer

11. Cleaning roller

12. Stripping roller

30




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


31




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


32




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


33




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


34




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


35




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


36




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


37




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


38




Yarn count:

Fibres:

Sliver count:

1. Feed roller




4. Fixed flats rear

5. Cylinder





10. Doffer

11. Cleaning roller


39

Notes:

40

Notes:

41

Notes:

42

Notes:

43

Notes:

44

Notes:

45

Notes:

46

Notes:

Documents

Carding Booklet