The document discusses developments in draw frame technology. Recent developments include higher production rates up to 1000 m/min, improved drafting systems like 4-over-3 with pressure bars, automatic sliver regularity controllers, quality monitoring systems, automatic doffing systems, and pre-set sliver length measuring. Additional new developments mentioned are automatic break draft setting, clean coil technology to reduce cleaning needs, pneumatic pressure heads for rollers, and tension measuring systems.
2. What is draw frame?
Draw Frame
Draw frame is a machine for combining and drawing slivers of a textile fiber (as of
hemp for rope manufacture or cotton for spinning). Drawing is the operation by
which slivers are blended, doubled and leveled. In short staple spinning the term is
only applied to the process at a draw frame.
In drawing slivers are elongated when passing through a group of pair rollers,
each pair is moving faster than previous one.
3. .
Objectives of draw frame
To straighten the fibers in
the slivers.
To make parallel the fibers
in their sliver axis.
Hooks created in the card
are straightened
through the suction
,intensive dust removal is
achieved
To make perfect blending
of the slivers.
To reduce irregularities of
fiber by doubling and
drafting.
To improve the uniformity
and evenness of the sliver
4. Task of draw frame
1.Equalizing
2.Parallelizing
3.Blending
4.Dust removal
Actions Involved in Draw Frame
Drafting: It is the process of increasing length per unit
due to peripheral speed of the rollers.
weight of sliver. It is mainly
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.
11. Introduction:
The Draw Frame is another important machine of the spinning mill because it also
magnifies the yarn. Quality of yarn is directly related to the quality of Draw Frame
Sliver, so the modern developments are carried out produce better Draw Frame sliver.
There are some common developments which are evolved such as Auto leveler, Can
Changing systems, suction devices etc… These are developing day by day to be more
precise by means of electronic and mechanical improvements.
12. RECENT DEVELOPMENT IN DRAW FRAME
Particular
Lakshmi Machine
Works Ltd.
Rieter Machine
works Ltd.
Vouk spa
TOYOTATextile
Machinery
Trützschler
GmbH & Co.
Model LR SB 851 RSB Unimax DX8 TD 03
Delivery speed
(max)
800 m/min 1100 m/min 1050 m/min 1000 m/min 1000 m/min
Drafting system
3-over-3 With
pressure bar
4-over-3 With
pressure bar
3-over-4 With
pressure bar
3-over-3 With
pressure bar
4-over-3 With
pressure bar
Draft range 3.05 to 11.6 4.5 to 11.6 4 to 11.6 4 to 14 4 to 11
Roller loading Pneumatic Pneumatic
Spring or
hydraulic
Spring Pneumatic
Autoleveller Yes Yes Yes Yes Yes
No of deliveries
Single or twin
(LD0/6)
Single or twin
(SB)
Single or twin
(Duomax)
Single or twin Sigle
Can system
(delivery)
Auto doffing
(round cans)
Auto doffing
(round or
rectangulatr cans)
Auto doffing
(round cans)
Auto doffing
(round cans)
Auto doffing
(round or
rectangulatr
cans)
13. Draw Frame Recent Developments:
01. High production rate – up to 1000 m/min delivery speed
02. Improve drafting system
a).4 over 3 with pressure bar
b).Roller pressure pneumatic
03. Automatic sliver regularity controller (Auto leveler)
04. Sliver quality monitoring system
→ Red (stop)
05. Fault locating indication lamp → Green (break)
→ Yellow (cane change)
06. Auto doffing
07. Pre – set sliver length measuring system
08. Rectangular can
Draw Frame Process Parameters:
Delivery speed 600 m/min
Sliver Wight → Feed → 60 – 70 gr/yds (7000 grain = 1 lbs)
→ Delivery → 60 – 70 gr/yds (1m = 1.09 yds)
Draft → 6 – 8
Doubling → 6 – 8
Wastage → 0.5% (Std)
Efficiency → 80 – 85%
14. Followings are some of other new developments.
Auto break draft setting - Incorrect break draft increases yarn U%. When there are
imperfections and neps, the total draft does not affect yarn quality much. So break draft
plays a very significant role in yarn quality and must be set correctly. In Trutzschler
new draw frames has this Technology and it optimize the sliver by estimating the
corresponding values of the break draft merely in one minute and takes important
parameters, like fibre-fibre friction, fibre to metal friction, etc and calculate the break
draft.
15. CLEAN coil - The deposition of spin finish on the underside of the coiler plate of
draw frame when processing MMF leads to displacement of the sliver layer in can. To
avoid this, the coiler has to be cleaned frequently resulting in production loss. Rieter has
patented a coiler plate that has honeycomb like surface and claimed to reduce cleaning
frequency from 2 to 3 hours to 1 - 3 days depending upon the type and quantity of
finishing agents.
Pneumatic Pressure Head for the drafting rollers. This technology can control the
pressure for sliver automatically and from that better fibre control can be achieved.
Tension measuring system – when the card sliver is fed to the draw frame, there is a
long path to travel. So on way there will be tension variations due to friction forces and
weight of the sliver. To avoid these tension variations there are tension measuring
sensors to detect and adjust the roller speeds according to it.
Short-term auto levelers - In principle, leveling takes place in the entire speed range of
the draw frame. Even when reducing speed before and during run-up after a can
change, short-term leveling (SERVO DRAFT) remains in operation. Due to this each
meter of draw frame sliver has its optimum quality.
16. Draw Frame LD 2
SALIENT FEATURES
•Delivery speed of upto 1000 m/min (mechanical) .
Technologically up to 800 mpm
•Spring loaded 4 over 3 pressure bar drafting arrangement for
controlled fibre flow
•Timing belt drive for noiseless transmission
•Delivery Can Size of 20” x 45” / 48”, 24” x 48” with can changer
and 40” x 48” without can changer
•Ergonomically designed creel for accommodating feed cans
upto 40” diameter
•Increases the efficiency of downstream process by upto 10%
•Reduces manpower requirements
17. DRAWFRAME LD2
The newly designed high speed non autoleveller draw frame model LD2 with two
delivery heads with automatic can changer for cans of upto 600 x 1200 mm (24” x 48”)
and delivery size of 40” x 48” without can changer arrangement enables the spinner to
reduce the cost of production considerably. With technological speeds of upto 800 mpm
(1000 mpm mechanical) , slivers of high evenness can be produced out of a wide range
of raw materials such as cotton, man-made fibres and blends.
HIGH SPEED TECHNOLOGY
High delivery speeds of upto 800 mpm are achieved by means of the design of the
drafting arrangement and the guidance of slivers. The design of the drafting system
ensures shorter web travel distance after parallelization, eliminating lengthy web guide
tube and guaranteeing less sliver breakage at high delivery speeds.
DRAFTING SYSTEM
The newly designed 4 over 3 pressure bar drafting arrangement with pneumatic
weighting system facilitates the machine to run at high delivery speeds. The drafting
system is equipped with spring loaded top rollers and the holding & releasing of the top
arm is through mechanical locking. Electrical stop motion is provided to
instantaneously stop the machine in case of roller lapping. The provision of adjustable
suction nozzles over the top rollers ensures cleaner slivers.
COILER ARRANGEMENT
The machine is equipped with two types of coiler arrangement, 40” Coiler – For delivery
can size of 40” x 48” without can changer arrangement and 20” / 24” Coiler – For
delivery can size of 20” and 24” with automatic can changer arrangement. Draw off
rollers are provided for production of compact sliver. Coiler is designed with a special
canal for low friction.
18. Draw Frame LDAZ
SALIENT FEATURES
•High delivery speed of up to 1,100 mpm (mechanical)
•4 Over 3 drafting arrangement with Pressure bar
•Centralized bottom roller setting
•Digital auto levelling system
•Integrated suction system for drafting, console, and sliver feed
at Scanning
•Filter box with auto clean arrangement
•Creel to suit feed Can 24” dia. x 48” ht. and Optionally
40” dia. x 48” ht.
•Delivery Cans dia. 16” to 24” with castor / Delivery Can ht. 42”, 45” and 48”
•Common Can changer arrangement for 18”, 20” and 24”
19. SCANNING SYSTEM & AUTO LEVELLING
Drawframe LDAZ works under the principle of open loop control system. Proven
tongue and groove rollers are used for scanning the feed sliver variations. Slivers show
unsurpassed evenness in the shor t, medium and long time range. These result in
quality output of the delivered sliver, 1mtr CV% of sliver by cut and weigh method as <
0.4.
DRAFTING SYSTEM
The machine is equipped with a new 4 over 3 drafting arrangement. The bottom rollers
are specially fluted and a technologically optimized profiled pressure bar is provided in
the main draft zone in order to control the floating fibres. These ensure optimum draft
to achieve better sliver evenness.
WEB COLLECTION
The web nozzle profile is optimized in order to achieve optimum sliver formation. The
shor test web travel distance after parallelization guarantees less sliver breakages and
higher delivery speeds. This increases the productivity and the efficiency of the
machine.
20. Draw Frame LDF3
Salient Features
•Deliver y speed of up to 1,100 mpm (mechanical)
•4 Over 3 drafting arrangement with Pressure bar
•Duo – Digital auto levelling system
Change Gearless Drive
•Inverter controlled main drive facilitates deliver y speed change from display
•– Stepless increase in speed
•– No change pulleys
•Servo motor drive to drafting
•– Main Draft adjustment through display
•– Elimination of main draft change pulleys
Quality
•Automatic suggestion of Autoleveller correction point based on Roller setting and Break draft
•Sliver monitor ensures the quality of output sliver
•Spectrogram for self diagnosis of mechanical faults
21. Use a camera to monitor the sliver quality
– This is used to monitor the output sliver
behalf on quality aspects such as fibre
arrangement, fibre imperfections and
irregularities. This is done by using a
camera which capture images of the
output sliver and compared with the
references by means of image processing
techniques. When there is an imperfection,
the machine is automatically adjusted to
eliminate by varying the machine speed
etc...
Simple and automatic adjustment of drafting zone widths - The drafting system rolls
are precisely positioned on parallel guides. Since the nip distance can be set by reading
on a dial, it is not necessary to use any gauges. Top roll support, top rolls and bottom
cylinders are firmly connected to each other and are automatically adjusted as well. Due
to a special belt guide, it is not necessary to tension again the belts after readjustment.
Use of microwave sensors – this is used in auto leveling to determine band mass of an
elongated, substantially non twisting fibre structure. This is used the moisture content
of the sliver as the measuring principle.