Its a Yarn Manufacturing subject topic.All about how draw frame works in industries and machine parts.

1. Study on draw
frame

2. The draw frame
 The draw frame is the quality filter of the
spinning mill errors in the draw frame sliver
result inevitably in yarn defect. since quality
can no longer be improved after the draw
frame the sliver quality at the last draw frame
passage is of decisive importance

3. Objects of draw frame
 To straighten the crimped and hook fibers in the card
sliver
 To achieve a fairly through parallelization of the fibers
along the sliver axis so that when they came to be spun
on the spinning frame they will be evenly drafted and
twisted to produce an acceptable yarn
 To improve the short medium and long term
unevenness of the sliver by doubling
 To produce a more uniform sliver of definite
weight/length
 To reduce the weight/unit length of the card sliver

4. A modern draw frame

5.  Actions Involved in Draw Frame
Drafting: It is the process of increasing length per unit weight of
sliver. It is mainly due to peripheral speed of the rollers.
Doubling: The process of combing two or more carded sliver
into a single form is called doubling. In draw frame m/c generally
six slivers are fed to convert into one i.e. six doubling.
Drawing: In the cotton industry the term is applied exclusively to
processing on the draw frame, where the operation is one of
doubling and drafting. Drawing= Drafting + Doubling.

7.  Tasks of Draw frame
Equalizing
 Parallelizing
 Blending
 Dust removal
 Equalizing: One of the main tasks of draw frame is improving evenness over short, medium
and especially long terms. Carded slivers are fed to the draw frame have degree on
unevenness that cannot be tolerated in practice and slivers from the comber contain the
“infamous” piecing. It is obscured by draw frame.
Equalizing is always performed by a first process, namely doubling and can optionally also
be performed by a second process, namely auto leveling. The draft and the doubling have
the same value and lie in the range of 6 to 8.
Parallelizing: To obtain an optional value for strength in the yarn characteristics, the fibers
must be arranged parallel in the fiber strand. The draw frame has the tasks of creating this
parallel arrangement. It fulfills the task by way of the draft, since every drafting step leads to
straightening the fibers.

8. Blending: In addition to the equalizing effect, doubling also
provides a degree of compensation of raw material variation
by blending. Their results are exploited in particular way in
the production of blended yarns comprising cotton or
synthetic blends. At the draw frame metering of the individual
components can be carried out very simply be selection of
the number of slivers entering the machines.
Dust Removal: Dust is steadily becoming a greater problem
both in processing and for the personnel involved. It is
therefore important to remove dust to the greatest practical
extent at every possible point within the overall process

9.  During drafting, the fibers must be moved relative to each other as uniformly as
possible by overcoming the cohesive friction. Uniformity implies in this context
that all fibers are controllably rearranged with a shift relative to each other equal
to the degree of draft.
 However, such regularity is utopian as regards both the fiber material and the
mechanical means available. Drafting operations always run irregularly, and
each draft stage will therefore always lead to an increase in unevenness.
 Drafting is effected mostly on roller-drafting arrangements (Fig. 43). The fibers
are firmly nipped between the bottom steel rollers and the weighted top
pressure rollers. If the rollers are now rotated in such a way that their peripheral
speed in the through flow direction increases from roller pair to roller pair, then
the drawing apart of the fibers, i.e. the draft, takes place. This is defined as the
ratio of the delivered length (LD) to feed length (LF), or the ratio of the
corresponding peripheral speeds:

10.  V =Ld/Lf=Vd/Vf
 Where
 V=peripheral speed of cylinder
 D=delivery
 F=feed
 The drafting arrangement illustrated has two sub
drafting zones normally
 A break draft zone(B):Vb=V2/V3
 A main draft zone(A):Vm=V1/V2
 The total draft is always the product of the individual
draft of the sum
 V total=V1*V2*V3…….Vn

11. Types of drafting arrangement
 Conventional 4 over4 roller drafting system
 It is the old model drafting system here 4top
rollers are on each one of the 4 bottom rollers.
It can be used for all fiber lengths.

12. 4 over 4 roller drafting system

13. 3 over 4 roller drafting system
 The characteristics feature of this
arrangement is engagement of the middle
pressure roller with two bottom rollers are
carried in a common cradle and are not
adjustable relative to each other. This types of
arrangement is now found mainly in the
combing room.

15. 3 over 3 roller drafting
arrangement
 It was first developed by platt in the 1960 as
and still used today. Infect, the pressure bar
arrangement is probably the most widely used
from of drafting arrangement for draw frame.
In the main drafting zone, a spatial guide
system is used for short fiber control

17. 4 over 3 roller drafting
arrangement
 This is also a 3 roller pressure bar drafting
arrangement but a forth roller with lower
loading is added to the delivery roller to act as
a guide. The top roller are uniform in diameter
and are large in order to keep the strain
imposed on them low.

19. 5 over 4 roller drag ting
arrangement
 In this arrangement 5 pneumatically loaded
pressure rollers rest on two large 90 mm and
two small 28 mm non adjustable bottom
rollers. The pressure rollers are suspended
from two yokes. They have diameter off 39
mm. all though the three middle rollers may
be replaced by rollers of 28 mm diameter
depending upon the circumstances.

21. Thankn you