Comber
Comber
Comber
Introduction:
Combing is a very important process for a spinning mill. The object of combing is removal of
short fibres, Neps, impurities and to improve the fibre length uniformity followed with
improvement in mean length. The removal of immature cotton, foreign matter and improvement
in fibre fineness and fibre bundle strength are the additional advantages of combing process. In
totality combing process significantly improves the cotton characteristics by removing the
useless fibres (i.e. Fibres which are not suitable for a particular end use) from the process. These
fibres are extracted as comber Noil waste. This Complete combing process carried out by action
of different combing elements. During combing process along with useless fibres good quality
fibres are also removed especially in modern high speed combers which are huge raw material &
financial losses for the industry. We have studied in detail the combing action of these different
combing elements w.r.t. removal of Neps, SFC % & other impurities with mean length
improvement. The object of this article is to present the effect of different combing elements on
cotton processed and how we can perfectly set these combing elements to get the better combing
process with respect to desire Quality, so we can achieve maximum removal of useless fibres
with minimum losses of good fibres.
Keywords:
Comber, Combing elements, Top Comb, Top comb penetration, Top comb penetration depth,
Feed/Nips, Nips/Minutes, Lap batt, Sliver, Noil, Unicomb, Afis Pro, Imperfection, classimat
faults.
History of Comber:
There are two competing combing technologies: the Noble (1853) comb (variants Lister,
Heilman (1846) and Holden) and the French comb. The Noble comb technology is inefficient,
hence most combing in the world is carried out on the French system. The French system is
superior as it combs the entire length of a fiber. Noble combs suffer from the problem that they
will not comb 2 mm of a fiber's length. The 2 mm is the distance between counter-rotating pins.
The French system is a rectilinear combing system as opposed to earlier woollen systems
developed in England. Although the Heilman and Noble comb was an original circular design
(also developed in min and 18–19th-century England) as it happens in modern history, English
mills didn't share technology – resulting in development of superior technology on continental
Europe in the mid-19th century, as in France.
Combing: It is the process which is used to upgrade the raw material. It influences the
following yarn quality
yarn evenness
strength
cleanness
smoothness
visual appearance
In addition to the above, combed cotton needs less twist than a carded yarn.
To produce an improvement in yarn quality, the comber must perform the following
operation.
elimination of short fibres as noil.
elimination of remaining impurities .
elimination of neps.
The basic operation of the comber is to improve the mean length or staple length by
removing the short fibres.
Trailing hooks from carding should be fed as leading hooks to reduce long fibre loss in
the noil.
Elimination of short fibers produces an improvement mainly in staple length, but also affects the
fineness of the raw material. The micronaire value of combed sliver is slightly higher than that of
feedstock (elimination of dead fibers). Also the degree of parallelization might reduce the inter-
fiber adhesion in the sliver to such an extent that fibers slide apart while being pulled out of the
can – i.e. sliver breaks or false drafts might be caused.
Types of Comber:
The major types of combers include:-
The basic elements of the combing machine are shown in figure. These are the feeding element,
the nipper plate, the combing system and the detaching rollers. The main function of the feeding
element is to feed the comber lap in a series of short lengths. The nipper plate grips the fibers as
a means of holding long fibers while the short fibers, neps, and trash are being removed.
The combing system consists of two combs. The first one is a rotating bottom circular comb that
performs the main combing action. The second one is a linear top comb that completes the
function of the bottom comb through vertical combing movement.
The detaching rolls are two pairs of gripping rolls that rotate forward and backward in intermittent
fashion to hold and move the combed web for a net forward travel. The objectives of combing
mentioned earlier are accomplished by a precise sequence and synchronized series of actions
performed by the combing elements. The following text will review this sequence of actions, or the
combing cycle, in a very simplified manner to demonstrate the function of each comber component.
SEQUENCE OF OPERATION IN A COMBER
Feeding, lap is fed by feed roller
fed lap gripped by the nipper
gripped lap is combed by circular comb
detaching roller grips the combed lap and moves forward
while the detaching roller delivers the material, top comb comes into action to further
clean the lap
While going back, nipper opens and receives a new bit of lap.
Types of feeds:
1. Forward feed (concurrent feed):Feed of the sheet into the nippers occurs while the
nippers move towards the detaching roller
2. Backward feed (counter-feed): Feed of the sheet occurs during return of the nippers.
PRODUCTION CALCULATIONS
Production of the comber is dependent upon the following:
Input feed:
Lap width: 270-300mm
No. of lap per machine: 8
Batt weight per meter: 60-80 gm/mt
Production data:
Lap diameter: up to 650mm
Feed per nip: 4.3/4.7/5.2/5.9mm
Noil: 8-25 %
Drafting system: 3/5
Doubling: 8 fold
Sliver weight: 3-6 kTex
Break draft: 1.14-1.5
Total draft: 9.0-23.1
Pressure:
Loading: pneumatic
Top detaching roller: 3-4bar
Drafting system front roll: 2.5-3bar
Drafting system 2nd and 3rd rolls: 3.5-4.5bar
Analysis by figure:
Conclusion:
All the above informations are collected for the acknowledgement of textile spinning learning
purpose. Thank you for enjoying.