Carding is a critical process in spinning mills that reduces fibers to a web by separating and orienting them, thus ensuring higher quality yarn. It involves multiple actions, including carding, stripping, doffing, and grinding, each serving specific functions like impurity removal, fiber blending, and sliver formation. The choice of card clothing material—flexible, semi-rigid, or metallic—affects production efficiency, fiber damage, and costs, highlighting the importance of optimizing carding parameters for effective fiber processing.

1. Carding: Heart of Spg :
Carding may be defined as the reduction of an entangled mass of fibres to a filmy web by
working between two closely spaced, relatively moving surface clothed with sharp wire
points. The carding is the heart of the spinning mill & well carded is half-spun-
demonstrate the immense significance of carding for the final result of the spinning
operation. The importance of carding is still greater where new spinning systems are
concerned.
Object/ function/ Task of carding:
1. Opening to individual fibers : The blow room only opens the raw material to flocks
where as the card opens it to the stage of individual fibres. This enables the
elimination of impurities and good performance of the other operation.
2. Elimination of Impurities and dust: Elimination of foreign matter occurs mainly in
the region of the taker in. In addition to free dust, which can be directly sucked
away as in the blow room, the card also removes a large proportion of the micro
particles. The card is a good dust removing m/c.
3. Disentangling of neps: The card reduces the no of neps from the blow room.
Actually neps are not eliminated at the card, they are mostly opened out. An
improvement in disentangling of neps is obtained by: closer spacing between the
clothing; sharper clothing; optimal speeds of the taken- in; low doffer speeds, lower
through put.
4. Elimination of short fibers: Short fibers can only be eliminated if they are pressed
into the clothing. Elimination of short fibers in the card must be viewed in
proportion, actually very small, fewer than, 1% short fibers.
5. Fiber blending: The card is the only m/c to process individual fibers. In formation
of the web and with repeated rotation of the fibers on the main cylinder, intimate
fiber with fiber mixing is achieved.
6. Fiber orientation: It is often attribute the effect of parallelizing. The card can be
given the task of creating partial longitudinal orientation of the fibers.
7. Sliver formation: To deposit the fiber material, to transport it and process it further
, an appropriate product must be formed.
So carding is called Heart of spinning”
Different action in card m/c:
I) Carding Action: If two closed surfaces have opposite wire direction and their speed
direction or relative motion is also opposite, then the action betn two surfaces is known
as carding action:

2.  It is occurred betn flat and cylinder.
 Here wire direction is opposite
 Speed direction is opposite
 If the two surfaces move in the same direction but at different speed.
 There always should be point against point direction.
Result by the action of carding –
 Maximum individualization of fibers isachieved in this region by opposite spikes.
 Neps, short fibers, dirt & dust are removed .
 The difference of surface speed betn cylinder & flat is more.
So carding action is maximum occurred
II) Stripping Action: When two close surfaces have same wire direction and their speed
direction or relative motion is also same then the action betn two surfaces is called
stripping action.
Stripping action is occurred betn
 Taker in and Cylinder
 Doffer and Stripper.

o Same wire direction & speed direction.
o There always should be point against back action.
Result by the action of stripping:
 Trash, reps are transferred from cylinder, taker in and taker in by stripping action.
III) Doffing action: When two close surfaces wire points are inclined in opposite
direction and their speed direction is same, then the action betn two surfaces is
called doffing.
 Stripping action is occurred betn cylinder and doffer

3.  Wire direction is opposite but speed direction is same.
 It is special type of carding
 Sliver formation – is done by this action.
IV) Combing action:
 This action take place betn feed roller & taker in
 Here pin direction is same.
Distinguish betn Carding action and stripping action:
Carding Action Stripping action
1. Two surfaces wire point are
inclined in opposite direction.
2. Their speed direction is opposite
3. It is occurred betn flat & cylinder
4. As in this action, two surfaces are
in opposite direction, so minimum
amount of fiber stay in lower
speedy surface.
5. Fibers are mainly individualized by
this action.
6. Point against point action.
1. Two surfaces wire point are inclined
at the same direction.
2. Their speed direction is same.
3. It is occurred betn (i) Taker in and
cylinder & (ii) Doffer and striper.
4. As in this action, two surfaces are
in the same direction, so maximum
amount of fiber stay in lower
speedy surface.
5. Fibers are mainly individualized by
this action.
6. Point against point action.
Distinguish betn Cording Action & Doffing action:
Carding Doffing
1. Two surfaces wire point are
inclined in opposite direction &
their speed direction is also
opposite.
2. It is occurred betn flat & cylinder
3. The speed difference betn two
surfaces are more.
4. Minm amount of fibre stay in lower
speedy surface.
5. Fibres are mainly individualized
by this action.
1. Two surfaces wire point are
inclined in opposite direction but
their speed direction is same.
2. It is occurred betn cylinder &
doffer.
3. The speed difference betn two
surfaces are less.
4. Some amount of fibre stay in lower
speedy surface.
5. Sliver formation is performed by
this action.
Operating principle of Modern high performance card:
 Raw materials is supplied from the pipe ducting(1) to the card chute(2). The transport
roller(3) forward the material to feed arrangement(4).
 The feed rollers pushes the sheet of fibres to the taker in(5). These flocks are passed over
the grid equipment(6) and transfer to the main cylinder(8).

4.  During passing the materials between (5) and (6) greater parts of impurities looses and
suction duct(7) carries the waste.
 The flock carries along the cylinder, penetrate to the flats(10) up to open individual
fibres the actual carding action cause during passes between these two device.
 The flats are consist of about 80-166 carding bar. Some of 30-45 flats carries with the
cylinder and the rest of are return run.
 During this return, a cleaning unit(11) separate the short fibres, neps and foreign
materials from the flats.
 Two fixed carding bar(9) and (12) are designed to assist the carding operation. After
carding, the cylinder carries loose fibres which lie parallel without hook and they are not
transportable. So a doffer(14) is used to combines the fibres into web.
 A stripping device(15) draw the web from the doffer. After calendar roller(16)
compressed the sliver to some extent. The coiler(18) deposits it in cans(17).
 The working roller, cylinder and flats are provided with clothing which becomes worn
during fibre processing and must be grounded at regular intervals.
Feature:
1. Production: Four times higher than conventional card m/c
2. Speed : Cylinder = 310 r pm, doffer = 7 to 35 rpm, taker in = 910 r pm.
3. Taker in region: Need extra cleaning and opening arrangement.
4. Here combing bar used instead of Mote knife
5. Feed end: Adjustable lap stand to accommodate up to 2.4˝ dia lap
6. Cylinder under casing: strong and distance betn two kept is least.
7. Stop motion: In high production carding m/c use and types of stop motion:
such as - feed end and cam stop.

5. 8. Flats: flat speed remains same but mechanically improvement is done.
9. Doffing: In high production carding m/c, use doffing roller instead of
doffing comb.
10. Suction Unit: Three or four suction units are used.
Advantage:
 High production
 Lower labour cost.
 Less doffing frequency
 Less wastage
 Less stripping
 Less grinding.
Card Clothing:
The inclined wires set in base material, which are covered around the surface of Taker-in,
cylinder, doffer and flat in the carding machine is called.Of all the individual components
of the card, the clothing has the greatest influence on quality and productivity.
Types of card clothing:
Card clothing is divided into three groups –
I) Flexible clothing.
II) Semi – rigid clothing
III) Metallic clothing
I) Flexible Clothing: These have hooks of round or oval wire set into elastic, multiple-ply
cloth backings. Each hook is
bent to a U-shape and is formed with a knee that flexes under bending load and returns to
its original position when the load is removed .Flexible clothing is used in cylinder, flats
and doffer.
Advantage:
 Point density is high, so cording action is good.

6.  Wire point flexible, so fiber damage is less.
 FiNer yarn count can be prepared
 If there is damage in any parts, needs repair in those of parts.
 Low cost.
Disadvantage:
 Foundation material i.e. Textile fabric, rubber required.
 Wires may be loose.
 Low production for stripping action.
 Grinding should be regular.
 Wire and foundation material may get damage because of they are both flexible.
 Fiber becomes lose for grinding action.
 Any carding angle cannot be chosen.
III) Metallic Clothing : These are continuous, self supporting wire structures in which
teeth are cut at the smallest possible spacing. They do not need any base material. The
wire has no knee. Metal surface of m/c acts as a metallic foundation. Now a days, they are
used in Taker-in, cylinder and doffer.
Advantage:
 Metallic clothing needed no separate foundation material but metal surface of m/c
acts as a foundation material.
 As teeth and foundation are both metallic, there is no possibility of “teeth loose”
 Any carding angle can be chosen.
 No change of tooth angle due to carding action and fiber do not embed to teeth. No
need of stripping. As a result, save much time.
 No need of regular grinding.
 Saved 3% good fiber and increase production 18-20% due to no need of stripping
and grinding.
Disadvantage:
 Carding action is not better due to less point density.
 More fiber damage due to metallic of teeth.
 Difficult to repair, complete reclothing necessary.

7.  Initial cost high
 Not suitable to prepare firer count.
 Liberates more fly and pollutes air.
 Requires higher starting torque.
Differentiate betn Flexible & Metallic card clothing:
Flexible card clothing Metallic card clothing
1. Teeth have knees.
2. There is possibility of damage of
foundation; the teeth become loose.
3. Any carding angle cannot be
chosen.
4. Regular grinding is necessary.
5. Stripping is necessary.
6. Carding action is good due to high
point density.
7. Only damaged portion can be
replaced.
8. Low cost.
1. Teeth have no knees.
2. There is no possibility of damage of
foundation; the teeth become loose
on foundation.
3. Any carding angle can be chosen.
4. Regular grinding is not necessary.
5. Stripping is not necessary.
6. Carding action is not better due to
less pint density.
7. Difficult to repair; complete
reclothing necessary.
8. High cost.
Advantage and disadvantage of Metallic clothing over flexible clothing:
I) Advantage of Metallic clothing over flexible clothing:
 Metallic clothing needed no separate foundation mtl and metal surface acts as a
foundation mtl.but Flexible clothing needed textile fabric ,rubber as foundation
material.
 There is no possibility of “teeth loose” in case of metallic clothing but there is
possibility of “flexible wire looses” of flexible clothing.
 Metallic clothing needed less grinding and stripping, but flexible clothing needed
regular grinding and stripping.
 Metallic clothing ensures chosen of any carding angle, but flexible clothing cannot
do this job.
 Teeth cannot be loose in case of metallic clothing and teeth can be loose of Flexible
Clothing.
II) Disadvantage:
 Incase of metallic clothing, carding action is not better due to less point density.
But carding action is better due to high point density.

8.  Metallic clothing is costly. But flexible clothing is cheap .
 More fiber damage in case of metallic clothing, less fibre damage in case of flexible
clothing.
 Difficult to repair, complete reclothing necessary in case of M.C. Incase of flexible
clothing, no difficult to repair; only damaged portion can be repaired.
 Finer yarn count cannot be prepared in case of M.C and finer yarn can be in F.C.
III) Semi–rigid clothing: These are less elastic than those of flexible clothings. These
backing are multiple-ply structures, with more plies, than the backing of flexible clothing,
comprising both cloth and plastics layers. The wires are not formed with a knee. The wires
cannot band and they do not need sharpening. When subjected to bending load, they are
therefore much less capable of yielding than flexible clothing.
Semi – rigid clothing is used in flat for wood and long staple fibre.
Advantage:
1. No need of frequent sharpening.
2. No need of stripping as well as there is no knee and no dirt and dust is stored.
Selection of Card clothing:
 Type and design of card.
 Rotational speed of cylinder.
 Production rate.
 Material through put.
 Raw material type (natural or synthetic fibers)
 Fiber characteristics (mainly fineness , length, bulk etc.)
 Overall quality requirements.
 Price of the clothing.
 Service offered by the clothing supplier.
Effectiveness of clothing influenced by following factors :
 The quality of wire.
 The gauge of wire (no. of wire per sq)
 The insertion angle of wire in the foundation.
 The angle formed at the knee.
 The relative heights of knees and points.
 The grinding of the point

9.  The density of the wires.
 The manner of insertion of the wires in the foundation.
The most important operating parameters of the clothing:
Several important factors & dimensions:
1. Point density.
2. Base width (a1)
3. Height of the clothing (h1)
4. Tooth pitch. (t)
5. Carding angle
6. The tooth point
7. The base of the tooth
8. Tooth hardness.
Carding angle:
This is the most important angle of the teeth, aggressiveness of the clothing, the hold on
the fibers is determined by carding angle.
The angle specifies the inclination of the leading face of the tooth to a vertical.
It is described as positive, negative or neutral.
The angle is neutral if the leading edge of the tooth lies in the vertical (00).
Carding angle normally fall into the following ranges:
Taker in → +50 to -100 (-150)
Cylinder → +120 to 270
Doffer → +200 to +400
Fig: (-) Carding angle (+) Carding angle
Card Clothing Unit/Point density and calculation for point density:
Point density means; point per unit surface area. Point density have significant effect on the
carding action. However, the number of the points and speed of the rotation of cylinder must be
considered.
i.e. Number of point Surface speed ( dN) = Constant


The higher point density, the better carding effect up to a certain optimum limit. After this limit,
negative effect are shown. This limit/ range is depends on the materials. Coarser count need
fewer point and it take up more space into the card. Finer fibre processed in more point,
because, if the fibre throughput is same then more fibre present into the card.
Calculation: Point density is referred by number of point per square inch or square centimeter.
The calculations are,

10. 2
2
645
Point/Inch
Base width(mm) Pitch(mm)
100
Point/cm
Base width(mm) Pitch(mm)




Pitch = Tip to tip of teeth distance.
So, the narrow the base, the more cylinder rotation (i.e. r is decreases) that is, the higher point
density.
Grinding:
Grinding is the operation by which the effectiveness of the wire points of all organs in the
carding m/c is maintained. Wire pints of different organs i.e. Taker-in, doffer, cylinder
and flats, loss their effectiveness in regular fiber processing and variable weight of wire
points and get irregular carding action. So grinding is necessary to make the points, sharp
after grinding, the height of wire is reduced.
If grinding is not done, due to the action of cotton and dirt with the wires the points of
wires (teeth) become round at the top (i.e. blunt) and loose their aggressiveness.
Objects of grinding:
 To increase Sharpness of the wire points.
 To keep equal height of wires.
 To get regular carding action and uniform sliver.
Types of Grinding:
1. Traverse wheel grinding or horse fall grinder.
2. Dead, long grinder.
1. Traverse wheel grinding: Traversing wheel grinding device contains an emery wheel of
3.5˝ width which performs grinding process by traversing motion, moving from one end
to another across the wire pints of different parts.
Advantage: I) Better grinding action.
II) No risk of hooking or fusing of wires.
2. Long roller grinding: This device provides a long roller, which moves over full width of
cylinder surface and performs grinding process.

11. Advantage:
I) It is suitable for high speed grinding.
II)It is used for low and medium count yam.
Card setting of Revolving flat card :
The main components of carding m/cs are taker in to cylinder, cylinder to flat, cylinder to
Doffer etc. have set the distance.
1. Feed plate to taker in: 0.009˝ - 0.012˝
2. Lap guide to edges of feed roller: 0.075˝ - 0.001˝
3. Mote knives to taker in:
Upper knife: 0.010˝
Lower knife: 0.012 to 0.015˝
4. Taker -in to taker- in under caging:
Forward edge: .030˝
Rare edge:
"
16
5
5. Taker -in to cylinder: 0.007˝
6. Flat to cylinder: heal end: 0.010˝
Toe end: 0.030˝
7. Flat to flat stripper: 0.032˝
8. Top feather edge sheet to cylinder:
Upper edge: 0.010 to 0.060˝
Lower edge: 0.032˝
9. Bottom sheet to cylinder:
Upper edge: 0.0324˝
Lower edge: 0.015˝
10. Cylinder to Doffer: 0.005˝
11. Doffer comb to Doffer: 0.012 to 0.015˝
12. Cylinder under caging to taker in: 0.032˝
13. Cylinder under caging to cylinder:
Back: 0.012˝
Middle: 0.032˝
Front: 0.064˝
14. Back sheet to cylinder:
Upper edge 0.010˝
Lower edge 0.012˝

12. Importance of setting betn cylinder & flat:
 The material gets carding action.
 Maximum individualization of fibre
 Removed of neps, short fibers, dust etc.
 Parallelization of fibers.
 Straightening of fibers.
Factors considered for optimum card settings: The optimum card setting are influenced
by the following factors:
 Type of material or staple length of material.
 Amount of trash to be removed.
 Weight of lap per unit length or lap hank.
 Waste percentage desired.
 General mechanical condition of the m/c and card clothing.
 Production rate.
 Types of card clothing.
 Fiber fineness.
Function of front percentage plate: The amount of strips removed by the flats can be
regulated by the adjustable top section of the front plate, the so-called percentage plate,
can regulate the amount of strips removed by the flats. The closer the settings between
cylinder wire and percentage plate, less strips are removed. With the closer setting of the
plate, the wire of the cylinder has a better grip in the fiber compared with wider setting
addition, air velocity at a closer setting might help to keep more fibers on the cylinder
surface.
Function of Heal & Toe Management: The slide surfaces on the bars are not ground level
but are slightly inclined. This arrangement is called heal and toe arrangement. When
viewed form the direction of the material flow the leading edge of each bar is spaced
further form the cylinder clothing than the trailing edge. The result of the arrangement is
that the fibers are not pushed along in front of the flats, but can pass underneath it i.e.
gentle action taker place.
Maintenance:
1. Stripping the clothing
2. Burnishing the clothing
3. Grinding of the clothing
4. Mounting of fillet
5. Oiling and greasing

13. 6. Attending to repair
7. Splicing of ropes.
8. Setting
9. Miscellaneous
1. Stripping the clothing:
If at all possible, metallic clothing should not be cleaned out with a revolving
brush, but rather with a hand scraper while the cylinder is rotated manually (not
by the motor drive). Rapidly rotating brushes create considerable metal-to-metal
friction (brush on semi-tooth-wire) and cause more wear on the clothing points
than do the fibers.
2. Burnishing the clothing:
A single brownish wears down the teeth more strongly then processing tens of
thousands of kilograms of materials. Occasionally, this proves necessary on the
doffer. Then though, burnishing must be carried out in the direction of the teeth
and not against them.
3. Grinding of the clothing:
a. Intervals between grinding:
Cylinder Flats
1st grind after 80-150000kg 120-150,000kg
Each additional grind after 80-120,000kg80-120,000kg
b. Depth of grind: The depth of grind is such that a plane surface with a sharp edge is
produced at the point of the tooth.
c. Grinding of the flats: There are two possibilities, namely grinding in the card under
normal production conditions or grinding of the flats in a special grinding m/c
after removing them from the card.
4. Mounting of fillet:
If broken wire is found in m/c, should be repair instantly. Generally fillet of
cylinder ,doffer is changed after each 26 days and in Taker- in one time in a month.
5. Oiling and greasing: Should be oiling and greasing daily.
6. Attending to repair:
Should repair the m/c instantly otherwise increase loss of production and risk of
dangerous.
7. Splicing of ropes: Should change rope after splicing.
8. Setting: Should observe card setting each ten days.
9. Miscellaneous: Each roller should be kept in stand not keep in floor.

14. Auxiliary Equipment:
I) Dust extractors on high performance card:
The card releases enormous quantities of dust and it is essential to ensure comprehensive
and immediate removal of this waste. For this, modern cards are fully enclosed and
subjected to permanent under pressure, so that dust and fly can no longer escape form the
m/c. Within the casing, suction removal system are provided at some or all of the
following positions:
 In the feed region
 At the entrance to the flats
 Within the flats
 At the exit from the flats
 Between the main cylinder and the doffer
 At the web detaching point
 Beneath the main cylinder.
 In the coiler.
The suction removal systems operate continuously to maintain constant conditions at the
card. The quantity of suction air per card lies in the range from about 2000 to 2500 m3/hr.
II) Waste disposal:
The card eliminates approx 4% waste in a carding room processing 500kg/hr; about 500kg
waste is produced per day in the three-shift operation. This waste falls into two categories:
 Dropping form below the cared.
 Flats and fitter stripping.
Filter waste can be removed manually but now -a-days, attendants can not be asked to
perform manual removal of taker in droppings. Modern cards are there fore fitted with
suction-waste-removal systems. These can operate either continuously or intermittently.
Card waste:
I) Motes and fly 33%
II) Flat strip 45%
III) Cylinder strip 16%
IV) Doffer Strip 2.5%
V) Clearer waste
VI) Sweeping waste
3.5%
VII) Reusable waste







Carding faults:
1.Sliver variation: causes

15.  Irregular and uneven feed.
 Damaged feed roller/doffer/calendar roller
 Wide setting of feed plate to feed roller and Taker in to cylinder.
 To much tension betn doffer and calendar roller and calendar roller to coiler head.
Remedies:
 Regular and even feeding
 Grinding doffer, making effective feed roller and calendar roller.
 Controlling tension is delivery region.
2. Cloudy web: Causes: -
 Over loading of wires
 Damaged wires on cylinder, doffer, flats taker -in
 Wider setting betn cylinder and flats.
 Feed plate is setted too far from taker- in
Remedies:
 Grinding the organs of card
 By correction the error setting.
 Improvement feed roller grip.
3. Hole in web: Causes:
 Damaged wire on organs of card especially on doffer.
 Various heights of wire points.
Remedies:
Location the damaged wire portions on doffer & replacing the damaged portion
skill fully and then leveling the new wires with the rest of doffer wire points.
4. High nep count : causes :
 In correct setting (e.g. doffer to cylinder, cylinder to flat)
 Dull or damaged cylinder, doffer or taken -in wires.
 Wider setting betn cylinder and flat or doffer and cylinder
 Too high R.H%
Remedies:
 Correction the incorrect setting
 Grinding wire points.
 Maintaining R.H%
For cotton R.H → 45-55%, Temp 70-800F
For synthetic, RH → 55-56% Temp 80-900F
5. Web sagging: Causes:

16.  Lower tension draft betn doffer and cylinder
 High doffer speed.
 Low humidity.
Remedies:
 Increasing tension draft betn doffer and cylinder
 Reducing doffer speed
 Maintaining humidity as 50-60%
Function of flats:
 Opening of flocks to individual fibers
 Elimination of remaining impurities.
 Elimination of some of the short fibers
 Untangling neps (possibly their elimination)
 Dust removal
 High degree of longitudinal orientation of the fibres.
Recent development of cotton card:
Using the following process holds the recent development of cotton card:
 Metal detector
 Auto leveling
 Continuous suction
 Chute feed system
 Electronic control system
 Each section is driven by separate motion.
How can reduce reps in card sliver:
1. Closer spacing betn the clothing.
2. Sharper clothing.
3. Optional speed of the taker in
4. Low doffer speed
5. Lower through put.
Influence of taker in speed on yarn quality:
The greatest part of opening and clearing of fiber takes place and performed by taker- in.
About 50% of fiber tuft is made individual fibers by taker- in.
The degree of fiber deterioration can be controlled by adjustment of:
 The thickness of the belt.
 The degree of openness of raw material in feed stock.
 The degree of orientation of fiber in feet stock

17.  The aggressiveness of the clothing
 The distance betn the devices
 The rotational velocity of the taker in the material through put.
Fig: Influence of the rotation rate of the taker-in on the yarn (A)parmameters comparison value in
%
(B) Taker in rotatation rate(rpm)
I- Neps, II- Thick places, III- Thin places, IV- Yarn evenness,
V- Yarn strength , VI- Imperfections
By the above graph, it is obvious that is taker in speed is less (i.e. 740rpm) the yarn
quality will be better than that of higher taker in speed (i.e. 1040 rpm). Lower speed will
cause less reps, thick place thin places, more yarn strength than that of higher speed.
Additional carding segments:
Carding aids can be applied at three positions:
 Under the taker- in
 Between the taker in and the flats
 Between the flats and the doffer
This aids are in the form of carding plates or carding bars in the religion of taker in (a)
plates are usually used, while bars are being located increasingly in the region of the main
cylinder (b) in
740 1040 740 1040 740 1040 740 1040 740 1040 740 1040
100
50
I II III IV V VI
A
B
%

18. case of carding segments, under taker- in grid bass are replaced by carding segments.
There the fiber and flock is guided over the following devices one after another.
(a) Mote knife-1 → (b) Carding segment-1
(c) Mote knife-2 → (d) Carding segment-2
Effect of carding segment on to carding action:
If carding segments are not used, the taker -in delivers more flock. These flocks are compressed
and poorly distribute across the taker -in and when they pass between the flats and cylinder, it
creates extra pressure on the clothing and also the carding action suffers.
But if segment are included-
We can ensure the
 Further opening
 Thinning out.
 Spreading out.
 And over all distribute on to the surface of the card.
Carding segment reduce the loading of flat/cylinder. The diagram illustrated the loading with
and without carding segment used. It is clear that, most open occurs, in the first flat.
The carding segment brings the following advantages:
sImprove the dirt and dust elimination.
1. Improve the speed of the flat and hence production increases.
2. The quality of yarn increases.
3. Improve the entangling neps.
4. Preservation of clothing, hence longer life of clothing.
5. Finer clothing can be used.
6. Cleaner cloth.

19. 7. Greater fibre orientation and more transfers the fibre to the doffer.
Advantage and Dis-advantages of Flat drive for its backward and forward movement.
Movement of the flat: The bar of the flat is individual as like toothed wheel and set it into the
sprocket. The end of the bar of drive flat slide over the continuous bend with metal to metal
friction. To reduce this friction and ensure a steady forward movement, crosrol are provided on
the both ends of the bar by ball-bearing to slide over the bend.
In this principle, the flat can be forward or backward movement i.e. same or opposite
movement to the cylinder.
For movement with(forward) cylinder-
i) The cylinder assist the drive to the flat.
ii) So removal stripping is easier.
But- i) It transport the immediate dirt through the hole machine.
There have some technical advantage in case Backward movement.
1) The bar of flat is cleaned when it come into relationship with the cylinder clothing of
doffer side. After that it moves towards the taker in and then filled up the bar above the
taker. Here disadvantages, the flat capacity is lost to till up. But advantages are, the
remain dirt is eliminated by this action when the fibre first enters into the flat above the
taker in.
2) To clean the fibre, the cylinder carry it into the flat and take up the dirt but the dirt are
not transport through the hole m/c. The Rieter flat is shown tat, the cleanness of the dirt
occurring into the first flat above the taker in.
A – Flat loading.
B – Number of flat bar in the mtl flow direction.
Advantages of carding segments: /Effect
1. Improved dirt and dust elimination.
2. Improved untangling of neps and speed increase and here a production
increases.
3. Preservation of clothing and hence longer life of clothing.
4. The possibility of using firer clothings.
5. Better yarn quality.
6. Less damage to the clothing.
7. Clearer clothings.
Typical Specification of card:
Part Angle wire Speed Dia
Taker in → +50 to -100 (-150) 600-1000 rpm 250mm

20. Cylinder → +120 to +270 250-600 1300 mm
Doffer → +200 to +400 5-15 rpm 600-750mm
Lap Roller → --- 1 ft/min 50 mm
Feed Roller → --- 1ft/min 55mm
What happens when:
I) DCP is changed
II) PCW is changed or Barrow wheel is changed.
III) Feed roller and doffer speed is changed.
IV) Take - in change of speed (Effect of taker-in)
I) DCP: Means Draft Change Pinion. During carding if need to change draft then pinion
generally changes. The no of the teeth of this changed DCP higher then draft will less.
If number of teeth is less then draft will high.
i.e DCP
draft
1

II) PCW: PCW means production change wheel. By the help of PCW, production can be
more or less. If we want to increase the production ,the number of teeth of the wheel
should be increase and if we want to decrease the production ,the no of teeth of the
wheel should be decrease.
i.e. production  pcw
III) Feed roller and doffer speed is changed:
Feed roller and doffer speed decreases, keeping the other parts of the m/c const then it
help to improve web quality. Because taker in, cylinder and flats act upon less material
so opening and cleaning action will be very good and finally carding action will be
high.
If feed roller and doffer speed increased, keeping the other parts of the m/c constant, then
it does not improve web quality. Because taker in, cylinder and flats act upon more
quantity material, so opening and cleaning action will be bad and finally carding
action will be bad .
Auto leveling:
For regular delivery or regular out put of material changing draft according to the change
of input amount is called auto leveling.
The main regulating position is feed, auto leveling is usually performed by adjusting the
feed roller speed. Virtually autoleveling devices exploit this possibility, adjustment of
delivery speed is hardly ever used.
A distinction should also be drawn between:

21. I) Short-term auto leveling systems, regulating lengths of product from 10-12
cm.
II) Medium-term auto leveling systems, for lengths above 3m
II) Long-term auto levelers above 20m
Control Systems of Auto leveling:
I) Open loop control
II) Close loop control
I) Open loop control:
A measuring sensor is provided in the region of the infeed for
Fig: Principle of open loop control
continuous detection of the actual value – mechanically, optically, pneumatically or
otherwise. A regulator compares the result with the set reference value, amplifies the
difference signal and feeds it to an adjusting device. Control by this chain of steps
requires an additional element, namely the store. Since the material has to travel certain
distance betn a measuring and adjusting points and arrives at the adjusting points with a
time delay, the signal must be held back in the store.
Disadvantage:
 Lack of self monitoring
 Vary exact values of the adjustment are required all times.
 If measuring sensor improper, not possible to control regularity.
Advantage:
 Accurate regularity maintaining is possible
 Suitable for compensate the variation of short to medium wave length.
II) Closed loop control:
The measuring sensor is arranged in the delivery region that is
D
C
B
A
t
E
A = Measuring sensor
B = Store
C = Amplifier
D = Adjusting Device
E = Adjusting Point
F = Set Value Input
F

22. Fig: Principle of open loop control
down stream from the adjusting device. The measuring point is after the adjusting point.
The same measuring, regulating and adjusting devices can be used, but no store is
reduced. If too much material passes through the sensor the regulating transmission
receives a negative signal (i.e. reduce speed) until the actual and set values coincide. The
measured portion has long passed the adjusting point when the adjusting signal arrives.
Advantage:
 Suitable for compenastation errors of longwavelength.
 A past of faults can be eliminated by it in 1st passage
Disadvantage:
 Can not eliminates picings as finely as open loop control
 Very costly
Pneumatic measuring device:
In normal card, a funnel is provided before the calender roller (2) in order to collect the
web in to a sliver.
This funnel is developed to form a measuring device. When fiber material enters into the
funnel (3) carries along quite an amount of air held betn the fibers. This generates a super
atmospheric air-pressure.
Fig: Pneumatic measuring system
D
A = Measuring sensor
C = Amplifier
D = Adjusting Device
F = Set Value Input
C
A
F

23. A lateral bore (5) in the funnel and corresponding leads, transmit the pressure into the
chamber of a pneumatic electrical pressure transducer. Comparison of the signal with a set
value enables the generation of pulses to control the electronic units in the regulating
equipment.
Advantage: Simplicity of the system which dues not require additional or sensitive
moving parts.
Disadvantage: The fibre fineness affect measurement and hence fineness variation can
lead to errors.
Characteristics of carded sliver:
1. Carded sliver are oriented in different direction
2. Not proper uniform
3. More wt/unit length
4. The mores fibers are projected out of the slivers.
5. Hook is present.
6. More short fibres %
7. Sliver Hank: 0.12-0.20
8. Draft → 85-100
9. Wt/yds / sliver 70-82 grains
10. Production per hr: 6-16 lbs
Difference between carded & combed yarn:
Carded yarn Combed yarn
1. The yarn that is obtained without
combing is called carded yarn.
1. The yarn that is obtained by combing is
called combed yarn.
2. Quality of carded yarn not better than
combed yarn.
2. Quality of combed yarn better than
carded yarn.
3. Short fibre% is high. 3. Short fibre% is low.
4. Combing action is not done here. 4. Combing action is done here.
5. Less strength. 5. Higher strength.
6. Irregular. 6. Regular.

24. Mathematical problem
Problem-01: Find out the sliver Hank of a Carding m/c from the following data:
Lap weight=14 ozs/yds
Draft=100, Waste=4%
Solution:
-3
Lxw
Lap count=
xW
1 1
840 0.875
=1.36x10
l
x
x
Ne

Mechanical draft=Actual draft x
100 %
100
waste

100x100=Actual draft(100-4)
Actual draft
10000
104.167
100 4
 

Again Delivery Hank=Actual draft x Feed hank
=104.167 X -3
1.36x10
=0.1416 Ne
Problem-02: Find out the production per day in lbs of a Modern Carding m/c from the
following data-
Doffer speed=200m/min
Delivery sliver weight-68grains/Yds
Waste=3%, Efficiency=95%
Tension draft=1.1
Solution:
Production per day=
200x1.09x60x24x68x0.95x1.1x(100-3)
100x7000
3091.13 lbs

Problem-03: A Carding m/c running with following-
RPM of feed roller=1.5
RPM of feed doffer=10
Dia of feed roller=2.25"
Dia of doffer=27"
Hank=0.14
Find Mechanical draft and production.
Mechanical draft
L=1Yds
w=1lb
=840Yds
W=14 ozs/yds
= lb/yds
=0.875 lb/yds

25. Surface speed pf doffer
Surface speed pf feed roller
10 27
80
1.5 2.25
x x
x x



 
Production=
10 27 60 0.95
11.41 /
36 0.14 840
x x x x
lb hr
x x

 
Problem-04: Find the production per shift of Carding machine
Doffer speed=400rpm
Doffer dia=27"
Hank of sliver=0.14
Efficiency= 85%
Tension draft=13
Solution:
x27x400x60x0.85
Production of the Card
36x0.14x840
408.52 /
lb hrs



Problem-05: Find the draft of Carding m/c if lap weight 500gm/m and sliver hank=0.122
Solution:
-3
Delivery hank
Draft=
Feed hank
Lxw
Feed hank or Lap count=
xW
1x1
=
840x1.0046
=1.18x10
l
Ne

500 /
500x0.9114
=
453.6
=1.0046 gm
W gm m

-3
0.122
Draft=
1.18x10
=1.02.95

Problem-06: Lap hank =0.0012 Ne, Sliver hank is 11. Find draft fo Carding m/c.
Solution:
Delivery hank
Draft=
Feed hank
11
= 9166.67
0.0012

Problem-07: Find actual draft of a Carding m/c for mechanical draft=86, Waste extraction=7%,
Lap hank is 0.0012, what will be sliver hank?
Solution:
Mechanical draft
Actual draft= x 100
100-waste%

26. 86
= x100 92.47
100-7
Delivery hank
Actual Draft=
Feed hank
elivery hank=92.47 x0.0012=0.1109
D


Problem-8: Find out Production /day in lb in Modern Carding m/c-
Doffer speed=200m/min
Doffer dia=27"
Delivery slivefr weight=68 grains/yds
Efficiency=95%, Tension draft=1.1
Waste=3%
Solution:
1 x1
=
68
840
7000
=0.122 Ne
Lxw
Sliver count
Wxl
x

200x1.09x60x24x x27x0.95x1.11x(100-3)
Production per day=
36x0.122x840
=7283.313756 lb/day


Problem-09: A Carding Spinning mill has 10 cards. It runs . Find out the production per dau in
kg from the following data-
Delivery speed=200m/min
Doffer dia=27"
Delivery sliver weight=70 grains/ yds
Card efficiency=95%,Dia of the feed roller=2.25"
Solution:
1 x1
Sliver hank= 0.11
70
840
7000
x

200x1.09x60x24x x27x0.95x10
Production per day=
36x0.11x840
=70267.37 lb/day
=31881.74 kg/day

W=68 grains/ yds
= lb/yds
[7000 grain=1 lb]