INDEX

1. Acknowledgement
2. Introduction
3. Carding
 Introduction of Carding
 Object of Carding Machine
 Machine Parts of Carding Machine
4. Actions In Carding
5. Wastage In Carding Machine
6. Flat
 Construction
 Types of Flat
 Movement of The Flat
7. Flat Waste And Its Reduction
8.
Acknowledgement
We would like to extend our sincere and heartful gratitude to our
teacher Dr. R.K. Malik who has helped us in the endeavour and
has always been very cooperative and without his cooperation,
guidance and encouragement the project could not have been what
it evolved to be.

We extend our heartful thanks to our faculty for their guidance

and constant supervision, as well as for providing necessary
information regarding the project.

We are also thankful to our parents for their courage and

encouragement.

At last but not the least, gratitude to all our friends who helped
us to complete this projects within limited time frame.
Introduction
The purpose of this report is to

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CARDING
Carding is a mechanical process that disentangles, cleans and intermixes fibres
to produce a continuous web or sliver suitable for subsequent processing. This
is achieved by passing the fibres between differentially moving surfaces
covered with card clothing. It breaks up locks and unorganised clumps of fibre
and then aligns the individual fibres to be parallel with each other. In preparing
wool fibre for spinning, carding is the step that comes after teasing.
The word is derived from the Latin carduss meaning thistle or teasel, as dried
vegetable teasels were first used to comb the raw wool.

 Objects of Carding Machine

1. Opening to individual fibres.

2. Elimination of impurities.
3. Elimination of dust.
4. Disentangling of naps.
5. Elimination of short fibres.
6. Fibre blending.
7. Fibre orientation.
8. Sliver formation.

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 CARDING MACHINE
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Machine Parts of Carding Machine
1. Ducting pipe.
2. Chute feed.
3. Feed roller.
4. Transport roller.
5. Brush roller.
6. Flat.
7. Fixed carding bars.
8. Taker in.
9. Grid bar.
10. Suction duct.
11. Main cylinder.
12. Doffer.
13. Stripping device.
14. Calendaring roller
15. Coiler.
16. Can.

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Action in Carding Machine
The following actions take place in a carding machine.
1. Combing action.
2. Carding action.
3. Stripping action.
4. Doffing action.
1. Combing action

Combing action takes place feed roller & taken in. Here the pin directions
of two surfaces are the same. Combing is the straightening & paralleling
of fibers & the removal of short fibres & impurities by using a comb or
combs which is assisted by roller & brushed.

2. Carding action

Carding action takes place between flat & cylinder.

In carding action,
 Directions of wire in two surfaces are opposite.
 The moving directions of roller are also opposite.
 One roller is slower & other is faster.
So carding action is known as “Point against point” action.
3. Stripping action

Stripping action takes place between,

a) Taker in and Cylinder &
b) Doffer and stripper.
In stripping action,
 Wire direction will be the same.
 Roller moving direction will be the same.
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  One roller will be faster than another.
So stripping action is known as “Point back point” action.

4. Doffing action

This action takes place between cylinder & doffer. In this place fibre is
transferred from cylinder to differ. Low speed doffer is called fibre form
of high speed cylinder & makes a condensed web for formation of sliver.

WASTAGE IN CARDING

Continuous waste collection system (WCS) has become an integral part of the
spinning mills especially in the preparatory section at the expense of
additional electricity. It is observed in a majority of the spinning mills that the
power spent on this system varies from 4% to 10% on the total energy
consumption considering all waste collection systems serving blowroom,
carding, combing, spinning and winding.
Most of the systems working in the spinning mills are basically similar in
construction, installation type, operation and performance. A study was
conducted on carding waste collection system (WCS) of a spinning mill to
reveal facts specifically in terms of energy saving. The selected mill is a
modernised mill and a full-fledged waste collection system is in place for each
section. The present study focused only on the carding section WCS.

Carding Waste Collection System

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Carding waste collection system in this mill has two main suction blowers with
compactors. One is dedicated for flats suction line and the other is for licker-in
wastes. Each blower is driven by 45kW motor through ‘V’ belt transmission
medium. The study was aimed with single point objective of varying the suction
pressure at the plenum (header) and to discover energy saving options out of
it.To proceed in this task, suction control damper was selected as a primary tool
to vary the suction pressure and the results are presented here with reference to
suction optimisation using control damper only.

Control (shut-off) Damper

The circular duct system is designed to evacuate wastes for 16 carding

machines but presently serving for 14 cards only. This single speed WCS
develops and maintains suction pressure without any leverage for feedback and
control. Manual control dampers fabricated with butterfly louvers are in use in
the inlet of plenum as well as on the duct risers (after the plenum) for shut-off
operation. The control damper has 9 positions and is provided with extended
handle to move from one position to other for suction control.
Existing operational setup (Original setup)

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The damper control of the suction system was set to deliver its full capacity to
an extent of about 180 mm WC suction pressure. The suction level at the
machine is higher than the required level of 80 mm WC. The pressure switch
was to trip the machine whenever the pressure drops below 80 mm WC and this
pressure setting was not altered throughout the study for better performance.

Study procedure
The study was characterised by simultaneous measurement of power and
suction pressure for various levels of openings such as 100%, 75%, 50% and
25%. The reference measurement point for suction pressure was fixed as
plenum in the case of upstream and card No. 16 in downstream.

Trial 1
The following table shows power and suction values corresponding to damper
position 8 (the existing condition).

Trial 2
The damper was moved from the position 8 to 6 by pulling the lever and the
measurement procedure was repeated.

Trial 3
The damper was moved from position 6 to 4. The corresponding power and
suction values are tabulated.

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Trial 4
The damper was moved from the position 4 to 2 and the study was ended. The
outcome of trials is consolidated in the following Table for analysis and
depicted in Figure 1.

Consolidate Information
It can be clearly seen from the above Table that the reduction in suction
pressure and power consumption are not proportional to each other with the
percentage reduction in damper position. Even a fifty per cent reduction in
damper control results only in minor reduction in power as well as suction.

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Conclusion

The following conclusions have been drawn from the energy audit trials.
 Control through shut-off damper is not an effective tool in terms of
smooth regulation of suction pressure
 Power saving observed was negligible compared to the drastic reduction
in suction pressure.
 Finally, it is a crude technique not suitable for suction optimisation
application and thereby energy saving, which was the primary aim.

FLATS
Together with the cylinder, the flats form the main carding zone. Here, the
following effects should be achieved:

1. Opening of tufts into individual fibres;

2. Elimination of remaining impurities;
3. Elimination of some of the short fibres;
4. Untangling neps (possibly their elimination); dust removal
5. High degree of longitudinal orientation of the fibres.

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Construction of the Flats

The bars of the flats are made of cast iron and are somewhat longer than the
operating width of the card, since they rest on adjustable (so-called flexible)
bends to the left and right of the main cylinder and must slide on these guide
surfaces. Each bar is approximately 32 - 35 mm wide (might change to smaller

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widths). The bars are given a ribbed form (T-shape) in order to prevent

longitudinal bending. A clothing strip (108 b) of the same width is stretched

over each bar and secured by clamping, using clips (c) pushed onto the left- and
right-hand sides of the assembly. Since some space is taken up by the upper
edge of each clip, only a strip about 22 mm wide remains for the clothing
(hooks or teeth). For this reason, the flats do not enable an absolutely
continuous carding surface to be formed above the cylinder; there are gaps
between the clothing strips.
The flats as used on the flat type carding machine designed for
processing cotton and fibres of similar staple length to cotton may be fixed in
relation to the carding cylinder or part of a chain of revolving flats which move
around part of the circumference of the carding cylinder.

Operation of Flats

 In order to fulfill all these requirements, a large continuous carding

surface is needed. The surface is created by a large number of individual
clothing strips secured to the bars of the flat (2) and arranged in
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  succession. 40 to 46 such strips are commonly used (30 in Trutzschler
machines) to make up the carding surface in the operating position.
 Elimination of Waste:
Since elimination of waste can be carried out only by filling the clothing,
the flats must be cleaned continuously. They must therefore be moved
past a cleaning device (4) (hence the name ‘the revolving flat cards’).
 Endless Path:
The bars of the flat must be joined together to form an endless, circulating
belt, for which purpose they are fixed to chains or toothed belts. In
addition to the 40-46 flats (2) (Reiter C 60 card: 27 flats) that interact
with the cylinder (1), further flats are needed for the return movement on
the endless path so that altogether 100-120 flats (Reiter 79).

Heel and Toe Arrangement

The slide surface on the bars are not ground level but are slightly inclined(in
fig.). Therefore, as the flats move over the cylinder, they have a slight tilt, i.e.
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viewed in the direction of material flow the leading edge of each bar is spaced
further from the cylinder clothing than the trailing edge (1).The result is that
the fibres are not pushed along in front of the flats, but can pass underneath
them.

Types of Flat
Flat are two types....
1. Revolving flat
2. Stationary flat
Revolving flat
Conventionally, the revolving flat is T-shaped and made of cast-iron, machined
to accept a top of card-clothing attached to its flange by steel clips, each end of
the flat being machined for correct location of the flat in close proximity to the
carding cylinder, against which the card-clothing top has to operate. The rib of
the flat is designed to provide the necessary stiffness to enable the flat to span
the width of the carding machine and ensure that an equal setting of the card-
clothing on the flat to that on the carding cylinder is sustainable over the
working width of the cylinder.

Stationary flats
Stationary flats can be used in addition to revolving flats or can be entirely
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substituted for revolving flats, such stationary flats being conventionally also T-
shaped in the form of an iron casting or an aluminium extrusion. The flange
carries a card-clothing top or other operative element such as a trash extracting
knife which is clipped or attached by screws to the surface of the flat, and the
rib is designed to support the flat correctly across the width of the carding
cylinder. The ends of the flat are machined to accept the setting and securing
arrangements for fixing the flat to the carding machine frame in its required
relationship to the carding cylinder.

With both stationary and revolving flats, when the card- clothing top or other
operative element becomes worn out or damaged, it is removed from the flat
and a new top or other element is clipped or screwed to the flat in replacement.
Replacement of the card-clothing top which is conventionally clipped or bonded
to the revolving flat involves the use of specialised machinery which adds to the
cost of the replacement. Replacement of the top which is screwed to the flat
requires investment in the specially designed flat adapted to receive a screw-on
type of top.

Movement of the flats

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The bars of the flats mesh individually, like an internally toothed wheel, with
the recesses in a sprocket gear, and are carried along by rotation of the sprocket.
The ends of the bars of the operative flats slide over a continuous bend with
metal-to-metal friction.

As the flats move at a very low speed compared with that of the cylinder in
principle, the flats can be moved forward or backward, i.e. in the same direction
as or in opposition to the cylinder.

If the flats move with the cylinder (forward), the cylinder assists in driving the
flats and the removal of strippings is easier. Forward movement therefore gives
design advantages. On the other hand, reverse movement (against the cylinder)
brings technological advantages. In this system, the flats come into operative
relationship with the cylinder clothing on the doffer side. At this stage, the flats
are in a clean condition.

They then move toward the licker-in and fill up during this movement. Part of
their receiving capacity is thus lost, but sufficient remains for elimination of
dirt, since this step takes place where the material first enters the flats.

At that position, above the licker-in, the cylinder carries the material to be
cleaned into the flats. The latter take up the dirt but do not transport it through
the whole machine as in the forward movement system; instead, the dirt is
immediately removed from the machine (directly at the point where the flats
leave the machine).

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Flat Top Bar Picture

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FLAT WASTE AND ITS REDUCTION
1. Cause- If wire point density, wire point profile, and wire point
height not maintained properly then there will be wastage of fibre.
Reduction- Maintain the wire point density, wire point profile and
wire point height properly.
2. Cause- Speed of flat is also directly related to the amount of waste
removed in the form of flat strip i.e. the higher the flat speed
heavier is the flat strips.
Reduction- Maintain the speed of flat to reduce flat strip.
3. Cause- If flat top wire are not aligned at specific angle , then flat
waste will increase because the flat will hold the fibres.
Reduction- The angle of the wires should be maintained properly.

4. Cause- If temperature and humidity is not according to the fibre ,

then flat waste will increase.
Reduction- Maintain the temperature and humidity according to
the fibre profile.
5. Cause- If the setting between the flat and cylinder is too wide, then
there will be formation of neps and knots.
If the setting between flat and cylinder is too close, then there will
be chances of loss of good fibre which will go with the flat waste.
Reduction- Maintain the setting between flat and cylinder for a
good carding action and to reduce the formation of neps and knots.
6. Cause-If there will be very less supply of fibre then flat wire and
cylinder wire will collapse with each other and wire angle change
which will decrease the rate of carding action.
Reduction- Maintain the supply of fibres as per needed by the
machine to keep a better carding action.
7. Cause- If there will be more supply of fibre between the flat and

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 the cylinder, then there will be more carding force between flat and
cylinder wire, then both flat and cylinder wire will get bend.
Reduction- Maintain the supply of fibres to keep the wire safe.
8. Cause- If proper cleaning of flat strip, naps, neps and foreign
matters not done then this will create hinderence in the carding
action.
Reduction- Proper cleaning of flat strips, neps, naps, and foreign
maters should be done.
9. Cause- Wider setting of top percent plate of front plate with
cylinder, increases the flat strips waste.
Reduction- Keep the setting of top plate and front plate
maintained.

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