BASICS OF ONLINE MONITORING OF MACHINE AND PROCESS PERFROMANCE AT DIFFERENT STAGES OF FABRIC PRODUCTION The machine and p rocess performance of the following stages of fabric production are monitored online. 1. Cone wi nding 2. Warping 3. Sizing 4. Weaving MODERN CONE WIDNING MACHINES The modern highly automated cone winding department is faced with ever increasing demands. Cross-wound packages with perfect winding-off qualities and long, knot free yarn lengths are required which in their size and form are adapted to the requirements of the subsequent processes. Added to this are the requirements for consistently higher quality of the wound yarn. Modern cone winding means constant optimizing of productivity while at the same time achieving the required quality. The co ne winding department is therefore almost ideally suited for the on-line monitoring of quality and productivity at all p roduction locations. In weaving the weft accumulator u nwinds yarn from a large weft supply packages and then releases a precise amount to the weft insertion element of the loom. Variations in winding tensions during fibre production are totally unacceptable as the slightest change in tension on the forming yarn will change its physical and dying properties. The advent of splicing yarns means that ends may be joined in such a way that the differences from the base yarn is virtually impossible to see. This has opened the way forproduction of full size packages of knotless yarns being produced from part packages of what once would have bee n simply waste. In a spinning plant this recovery can represent substantial savings. FULL CONE MONITORS In cone winding, maintaining uniform and specified cone weight is major problem in almost all the mills. Various methods are followed to maintain the cone weight. The weight variations between cones, occurs mainly because of the variations in cop weight and also the breakage between the cops. This problem has become acute after the introduction of electronic clearers. This results in low cone winding productivity, weight complaints from the customers and increased cost of production. Hence full cone monitor has become essential to manage the above problems.
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8/6/2019 Copy of 35174000 Computer Application in Textiles 3 Vig Dhanabalan Pavitra
BASICS OF ONLINE MONITORING OF MACHINE AND PROCESS PERFROMANCE AT
DIFFERENT STAGES OF FABRIC PRODUCTION
The machine and process performance of the following stages of fabric production are monitored
online.
1. Cone winding
2. Warping
3. Sizing
4. Weaving
MODERN CONE WIDNING MACHINES
The modern highly automated cone winding department is faced with ever increasing
demands. Cross-wound packages with perfect winding-off qualities and long, knot free yarnlengths are required which in their size and form are adapted to the requirements of the
subsequent processes. Added to this are the requirements for consistently higher quality of the
wound yarn. Modern cone winding means constant optimizing of productivity while at the same
time achieving the required quality. The cone winding department is therefore almost ideally
suited for the on-line monitoring of quality and productivity at all production locations.
In weaving the weft accumulator unwinds yarn from a large weft supply packages and then
releases a precise amount to the weft insertion element of the loom.
Variations in winding tensions during fibre production are totally unacceptable as theslightest change in tension on the forming yarn will change its physical and dying properties.
The advent of splicing yarns means that ends may be joined in such a way that the
differences from the base yarn is virtually impossible to see. This has opened the way for
production of full size packages of knotless yarns being produced from part packages of what
once would have been simply waste. In a spinning plant this recovery can represent substantial
savings.
FULL CONE MONITORS
In cone winding, maintaining uniform and specified cone weight is major problem inalmost all the mills. Various methods are followed to maintain the cone weight. The weight
variations between cones, occurs mainly because of the variations in cop weight and also the
breakage between the cops. This problem has become acute after the introduction of electronic
clearers. This results in low cone winding productivity, weight complaints from the customers
and increased cost of production. Hence full cone monitor has become essential to manage the
above problems.
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In manual cone winding machines, an attempt was made by providing ring in the
cone holder. When the cone touches this ring, the winder will doff the cone. This methodcauses damages or strains to the cone and hence was not successful.
2. Cyclic cop replenishment
Mills normally provide cone weight tolerance ranging from 10grams to 25 grams
for every cone. Hence, if the cop weight is maintained within plus or minus 2 grams and the
breakage rate is less than 2 per lakh meters, then the winders can follow cyclic cop
replenishment method, check our cone weight after attaining the specified size and doff all the
cones. If the variation between cops is high, then the winders have to spend not less than 0.5
minute for every cone by keeping all other drums idle by following winding and rewinding
method. When they do not wind, after weighing, it leads to cone defects.
3. Measuring discs
In this method, the yarn is passed over a measuring disc. The pulses from the disc are
converted into length and thus the cone is monitored. This system has not become
commercially successful because of high cost.
4. Template
Some mills use templates to measure the cone size and doff the full cones. The cone size
vary depending upon the climatic conditions, unwinding tension and winding tensiongiven to the yarn. Hence, this method has also failed.
AUTOMATIC DOFFER
• Doffing is carried out when the package reaches the pre-set meter age or diameter,
which can be set from 125 mm to 300 mm maximum.
• Auto doffing is carried out by one or two doffers.
• The doffers doff the package and deposits over the conveyor
• It restarts the heads
• These doffers are moved by a motor at a speed of 24 m/min on a track.
Operation Logic
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The cut yarn ends are sucked into the untwisting nosily pipe and untwisted. At this time,
the yarn guide lever-R returns a little to allow a sufficient length of yarn to be twisted.
4. Splicing
The yarn guide lever-R is pushed in again, and it pulls the yarn ends out of the untwisting
nozzle. While the yarn ends are out they are held by the yarn holding lever, and a jet of
compressed air from the splicing nozzle tangles and twists the yarn ends together to
complete the splicing.
ELECTRONIC YARN CLEARER
Electronic yarn clearer functions either based on capacitance principle or photoelectric principle.
The setting is kept depending on the yarn count and the fault is identified based on the thickness
of the fault in the yarn and as well as the length of the fault.
The yarn is passed through the capacitors. Whenever there is variation in the yarn thickness and
also the length of the fault, the capacitance changes. This pulse is amplified and the knife is
activated by the sensitivity control and the yarn is cut.
The yarn passes through the light beam. Depending on the variation in the light intensity, the
photosensitive device gives the signal which is amplified and the knife is activated by the
sensitivity control and the yarn is cut.
WARPING
Warping is the process of winding warp threads on to a beam that can be used as the
warper’s beam in the further process of weaving. This is done with the help of a warping
machine. In this process the supply packages in the form of cones or cheeses are mounted on a
creel and the number of supply packages in the creel determines the number of ends in the beam.
The warp ends are fed in the form of a sheet wound on a beam in which all ends are parallel to
each other. Warping can be classified into direct beam warping and sectional warping. The of
control systems in this process is significant and directly influences the quality like the
appearance of the fabric that is finally woven in a loom. Warp specifications can be stored for
different parameters that are memorized by the PLC and can also be obtained even during power
failure. This PLC base control can also produce the data in a printout form. A Digital NumericalControl ensures that all beams are of the same length. It calculates the number of metres by
continuously measuring the circumference of the beam.
Controls in warping
1. Automatic Feed control system:
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The supertronic section warper measures the take up behavior of the warp material after the
first section is started and then adapts the feed automatically. The measuring system employs a
high precision electronic micrometer. After a small amount of material has been wound on, the
machine stops at a defined drum position. The measuring system relays the material height to the
computer. The machine is then restarted and continues warping until the second measuring stop,
which again takes place after only a few millimeters have been built up. The measuring operation
is repeated and the computer works out the correct feed from the two measurements.
2. Automatic Tension Controller:
The yarn tension while warping continuously changes during the course of the process. To
regulate the tension of the yarn from the supply package, it is necessary to control the yarn
tension. The required yarn tension in warp section is precisely set on electronic tension sensor
meter. The set value of creel tension is continuously monitored by pressure load cells mounted
on warp table. When there is loss in tension it gives a signal to the creel PLC, which in turn
regulates the yarn tension very precisely so as to get perfect warping in all sections. This is themost important feature required for preparing highest quality sectional warp beams for onward
sizing operation.
3. Automatic warp divider:
Electronically controlled feed roller that ensures that all sections in the conical area are of the
same height, thus ensuring that every end of the beam is of the same length. The lateral traverse
is computed electronically. A feed roller is laid against the drum surface and its position is
registered. The section is then run-on, pushing the roller back in accordance with the build-up.
An electronic transmitter device divides the distance travelled into timed impulses, which are fedto the computer that calculates the rate of traverse and displays it digitally.
4. Precision Length Measuring Unit:
A presser roller presses on to the circumference of the beam and senses the build in diameter of
the beam. This type of presser is used in case of grey yarns. When the set value is reached the
machine is automatically stopped and the beam can be removed from the warper. When dyed
yarns are used, the presser roller may abrade the colour on the yarn and hence laser-sensing is
used for sensing the diameter of the warp beam. The computer controlled wind-up of the beam
guarantees the identity of all sectional beams of the warping set. During the warping process, the
diameter of the beam is measured by a LASER system. The computer compares the current
warping values with the given values of the master beam and be adjusted by alternating of the
revolutions.
5. Automatic braking system:
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Block Diagram of Photoelectric Type Electronic Yarn Clearer
The block diagram shows the principle of the photo-cell type electronic yarn clearer. The
yarn is passed through a light source and is scanned by the light source. Opposite to the light
source, a receiver is provided to receive the light rays emitted from the light beam.
The yarn faults, limits for thickness, length and spinner’s double are set by using suitable
knobs in the instrument. As the yarn passes through the light source, the yarn is scanned by the
light beam. The scanned portion interrupts the light beam which changes the signal from photo-cell. These signals are fed to an amplifier which amplifies the signals. The amplified voltage is
transferred to a discriminator which measures the pre-set fault limits. If the signals exceed the
limits, the signal is fed forward and through cutting impulse, a knife is actuated to cut the yarn.
LIGHT
SOURCE
PHOTO
SENSITIVE
DEVICE
KNIFE
ACTUATOR
SLUB SIZE
DISCRIMINATO
R
AMPLIFIER
TEMPERATURE
STABILISER
LIGHT
COMPENSATOR
SENSITIVITY
CONTROL
LIGHT
SOURCE
KNIFE ACTUATOR
SLUB SIZE
DISCRIMINATO
R
AMPLIFIER
TEMPERATURE
STABILISER
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If sensors and measuring instruments are used in the textile industry in the appropriate
manner, production process becomes safer and reproducibility is improved. This increases the
level of quality and productivity while reducing energy costs resulting in lower manufacturing
costs for any given textile material. To obtain these objectives sensors, measuring and controldevices are proposed.Sizing is a very important process to produce warps for weaving. If the size
application can be successfully controlled by the control system, the size application can be
uniform without safety reserves.
Modern sizing machines from SUKER, MULLER, BENNIGER, ZELL, TOYOTA are
having sensor controlled systems which monitor the process and operating condition and
maintain at set level, so the machine can run without stoppage and uniform size will be applied.
The following controls are employed in sizing
• Temperature control
• Size level control
• Automatic tension control on single end sizing
• Stretch control
• Size application measurement control
TEMPERATURE CONTROL
It determines the viscosity of the size paste which plays a decisive role which in turn
determines the following:
1. Percentage of size pickup
2. Size penetration
3. End breakages during weaving
The thermostat tube is inserted into the size paste through a hole on the side of the size box. It is
connected to the throttling valve by means of a capillary tube. The thermostat is equipped with atemperature setting unit which can be adjusted by means of a key at the end of the thermostat
tube. The throttling valve is situated in the steam supply line. A bypass arrangement is also
provided to supply the steam directly to the size box. In such cases the valves X and Y should
remain closed and the valve Z should be open. When temperature of the size mixture in the size
box reaches the predetermined degree, the fluid in the thermostat tube expands along the
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The electrically operated controlling device uses two electrodes located in the size mixture. The
electrode conductivity of the size paste itself provides the basis for the application of the level
control system. A slight difference between the electrodes prevents the system of cyclic opening
and closing of the size-flow value due to turbulence or foaming in the size box. When the sizelevel falls below the lower electrode the circuit is broken and the electro pneumatic relay is de-
energized and the air operated valve controlling the flow of the size paste is open. When the size
paste level rises and reaches the upper electrode the electric circuit is closed and the relay closes
the control valve.
The system maintains the size level within + or – 5mm of the desired level. The disadvantage of
this deposition of the size material on the electrode affects the working of the control device.
This problem can be overcome by coating the electrode with Teflon material. In the place of the
air operated control valve a solenoid operated control can also be used.
AUTOMATIC TENSION CONTROL ON SINGLE END SIZING
Section Beams Loom Beam
TG IM
TG PC MB
PB PB PB TG
Tension set Winding Tension set
Taper Tension set Speed set
PB- Power Brake M- Motor
PC – Power Clutch IM –Induction Motor
MB – Mechanical Brake TG – Tacho generator
Tension
Controlle
Speed
Controlle
r
Tension
Controlle
r
M
MM
M
M
TensionControlle
r
Speed
Controlle
r
Tension
Controlle
r
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The headstock is designed to operate at high speed of 140-150m/min. The winding
tension is also high. Each beam has a power brake impulse from the beam tension controller.the
power brake not only deal with emergency stops but controls the creel tension by progressively
reducing the braking torque as the beams are reduced in unwinding diameter. The draw roll in
the head stock is driven through a power clutch which is imposed from a second tension
controller. Both controller have independent settings and are interconnected and each separately
linked to the Tacho-generator. The creel power brakes are also capable of providing taper-
tension or tension gradient down the weaver’s beam.
STRETCH CONTROL
BTRA has recently developed a digital stretch meter specially designed for continuous
monitoring of percent stretch on sizing machines. The display unit along with the sensing units
consists of two special transducers and the display unit. One of the transducers is mounted on the
guide roller preceding the sow-box. The other transducer is placed on one of the rollers of the
drag roller assembly at the headstock. The pulses generated by the transducers are processed byan electronic circuit and the result is digitally displayed as percent stretch. The gadget is useful
as it gives the operating stretch instantaneously thus is facilitating corrective action whenever
necessary. One display unit can cater to three sizing machines, while a pair of transducers is
required separately for each machine. The salient features of this stretch meter are its fully solid
state circuitry, high accuracy and easily readable bright red display. The construction of the unit
is robust which help to withstand vibrations and hot humid conditions.
SIZE APPLICATION MEASUREMENT CONTROL
The moisture content of sized warp is measured continuously after the yarn passes through the
sizing trough and before the drier without contact and free of inertia by means of microwave
absorption. With constant size liquor concentration, a change in moisture content means an
immediate change in the degree of sizing.
Transducer
1
Display Unit
Electronic
Circuit Transducer
2
Guide roller Drag rollerSow-Box Headstock
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The microwave measuring heads are mounted on a stainless steel measuring frame. Since steam
clouds and high temperature occur behind the sizing trough, the measuring heads are protected
by a temperature controlled warm air cushion, a warm air unit producing hot air, which heats the
entire measuring frame and washes round each measuring head.
Measuring faults due to steam clouds are thus avoided and the measuring heads are protectedagainst too high temperature and condensation on the measuring frame and consequently
droplets on the fabric are prevented.
AS measurements can be processed visually with PLC for controlling squeeze roller pressure in
the sizing trough. In order to meet the special sizing requirements, special control algorithm have
been developed, guaranteeing a uniform degree of sizing at any time and thus maximum weaving
efficiency.
Size application is affected by numerous parameters.
• Speed
• Squeeze pressure
• Squeeze roller hardness
• Liquor temperature
The effect of all of this parameters can be identified on time with the size application meter AS.
Sizing can be largely uniform with consistent use of the AS 120 and size application control.
Sizing Trough Drier
AS
Digital
Display
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Electronic Monitoring devices on Rapier weaving machines
Electronics are used on rapier machines primarily for weft monitoring. For rapier weaving
machines operating on the Dewas system (tip transfer), the piezoelectric monitoring system is
used for preference. The weft thread without any additional tensioning is passed at low angle
over the sensing unit. The start duration of monitoring are determined by the control system. TheLoepfe system consists of a stationary coil and a switching quadrant rotating with the weaving
machine crankshaft. A signal is thus produced by induction. Eltex uses a light cell for control
which operates in conjunction with a marker on the crankshaft as an electronic switch. On
electronic weft detectors for rapier weaving machines have shown that the required minimum
speeds for the positive functioning of the device on the Dewas weft insertion system is
dependent upon the following criteria.
1) The warp-round angle of the weft thread
2) The thread material
3) The yarn count and
4) The potentiometer setting
It was demonstrated that a certain “pressure” must be exerted on thread guide eye or the warp-
round pin for the weft detector to be able to register any thread movement. The following
advantages of electronic compared with mechanical weft yarn detectors may be quoted
Monitoring of weft yarns of all types over the full working width
No movable sensing parts
Simple mounting, adjustment and maintenance
Monitoring of single, double and multiple weft insertion, and
Low thread tension and no weft thread breaks in the centre of the cloth
Real time monitoring and planning for weave room
Real time machine monitoring and production reporting is still one of the primary functions of a
CIM system for a textile plant. Weave Master is a loom monitoring system. Through a GraphicalUser Interface(GUI), Weave master users are constantly informed about the actual situation in
the weave room resulting in faster reactions to problems and an increased efficiency. Powerful
analysis tools allows quick identification of poor performing machines and bottlenecks in
planning, resulting in an optimal usage of production capacities. With today’s small order
quantities and short delivery times, scheduling has become a critical function for the textile mill.
Weave Master offers the planning department an interactive tool allowing them to optimize loom
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loading based on real time information. Using the World Wide Web, the salesman can give
immediate and correct information about deliveries.
Color Mill:
The most important real time analysis tool of the Weave Master is the Color Mill. On this colour coded lay-out of the mill, the machines are pictured in a number of colour, each colour indicating
a certain machine status or alarm condition. From a data selection window, the user selects the
type of information to be displayed: efficiency, speeds, stop rates etc., For each data item,
exception limits can be defined and problem machines are automatically flagged. User definable
“filter sets” allow the user to display only these machines which correspond with a certain
condition, for example all machines with an efficiency less than 85%, all machines waiting for
an intervention, all machines weaving a specific style etc., A “mouse click” on a specific
machine opens a window with a detailed report showing all required information for the selected
machines. As a unique feature within Weave Master, these detail reports may contain any user
defined mixture of text and graphics.
Cockpit view:
The Cockpit view is the ultimate analysis tool for the plant manager and the industrial engineer.
Four graphs show the vital information needed to take quick decisions at the glance of just one
screen.
Film Report:
The film report is the result of an automatic machine activity sampling carried out by Weave
master. Based on user definable time intervals, the film report makes a complete machinediagonistic and shows whether efficiency loses were due to one long stop or were caused by
several short stops.
Electronic yarn tension control:
An additional tension meter allows you to quickly measure weft tensions accurately. The
portable and precise sensor is connected to the microprocessor of the machine. The tension
values are displayed as a graph, so that operator obtains the information needed to fine-tune and
control setting very fast. Fine-tuning and troubleshooting is easy thanks to the immediate
feedback. The results are repeatable and reproducible on other machines.
Using the tension meter will have a direct impact on productivity and quality. Each prewinder
can be equipped with a new type of Programmable Filling Tensioner (PFT). This PFT is
microprocessor-controlled and ensures optimum yarn tension during complete insertion cycle.
Reducing the basic tension is an important advantage when picking up weak yarns, while adding
tension is an advantage at transfer of the yarns and avoids the formation of loops. The tension
control enables you to weave strong or weak yarns at even higher speeds. It also drastically
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Technology is radically changing the relationship between the designer and the finished product.
As the work that occupies the space between the designer and consumer is now capable of being
totally automated, job functions, job descriptions and the entire product development and
production process are changing. Software simplify and streamline the endless repetition that gointo producing designs, revising size specifications, costing, infact the entire product
development process.
Textile CAD refers to products for Fabric Design. The software is not only meant to assist you in
design but also for further implementation to different production procedures. Apart from the
vast array of facilities, the three main applications of any of our products are
1. Research and Development of Design and Fabric
2. Production Planning and Implementation
3. Presentation for Marketing and sales
Design creation softwares
Some of the design creation software used are
• Adobe Photoshop
• Adobe Illustrator
•
Corel draw
• Photo Paint
• Micrografx picture publisher
• MS paint etc.,
Software Companies
• Textronics
• Wonder Weaves System
• Dream weavers
• TDS Jacquard
Software Development
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