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PROJECT REPORTSummer Training
WEAVING DEPARTMENT
Trident Home Textiles Unit: 2
Dhaula Complex, Barnala
UNDER THE GUIDANCE OF:Mr. A.K.S. GANGWAR
SUBMITTED BY:SHIVAM SHANDILYA
B. Tech. (FINAL YEAR), UPTTI, KANPUR
ACKNOWLEDGEMENT
I would like to thank Mr. SURENDRA SWAMY and Mr. R.B. MISHRA who has been a great support and guide during my training period. The project given by him has proved to be a source of immense learning for me.
I express my sincere gratitude to Mr. A.K.S. GANGWAR who constantly guided me and
helped me at every stage with their valuable suggestions and ideas.
I would also like to thank the director of the institute Mr. ALOK KUMAR and special
thanks to Mr. V.K. MALHOTRA for constantly encouraging me to go ahead towards my
work. I am also very thankful to all the people working in Trident who co-operated with
me and were a great help during my PROJECT.
Thank you all for everything.
To find out basic causes of warp breakage and to reduce warp breaks/cmpx in the loom shed.
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A dissertation submitted in Partial fulfilment of the requirement of the degree of
BACHELOR OF TECHNOLOGY
In
TEXTILE TECHNOLOGY
By
SHIVAM SHANDILYA
B.TECH (FINAL YEAR)
Under the guidance of
Mr. A.K.S. Gangwar
Uttar Pradesh Textile Technology Institute, Kanpur-208001
Session: 2012-13
CERTIFICATE
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This is to certify that the dissertation entitled “To find out basic causes of warp breakages and to
reduce the warp breaks/cmpx in the loom shed” by Shivam Shandilya submitted to the Department
of Textile Technology, UPTTI, Kanpur in the partial fulfillment of requirement for the award of
degree of Bachelor of Technology in Textile Technology is a record of bonafide work done by him
under my supervision and guidance during the session 2012-13. This work has not been submitted to
any other university or institute for the award of any degree or diploma.
Mr. A.K.S. Gangwar
Department of Textile Technology
U.P.T.T.I
Kanpur-208001
CONTENTS
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S.No. Title
1. Introduction…………………………………………………………………………
2. Acknowledgement…………………………………………………………………..
3. Literature…………………………………………………………………………….
4. Objective…………………………………………………………………………….
5. Materials & Methods………………………………………………………………...
6. Cost Benefit…………………………………………………………………………
7. Inferences…………………………………………………………………………....
8. Conclusions………………………………………………………………………….
9. References…………………………………………………………………………..
INTRODUCTION
Textile – Fibre to Fabric Processing
Abstract:
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This paper is an attempt to provide all basic information related to textile Industry – in the field of
manufacturing, purchasing, promoting, selling and so on. This article covers comprehensive outline
of fibres and steps involved in conversion of fibre to variety of yarns, fabric manufacturing and wet
processing of fabric for value addition.
Introduction:
Textile industry is one of the few basic industries, which is characterised as a necessary component
of human life. One may classify it as a more glamorous industry, but whatever it is, it provides with
the basic requirement called clothes. There are numerous kinds of fibres and other raw materials,
which are used to produce a cloth. This paper provides an insight about the basics of textiles and the
terms that are used all around the world in context of textile industry. Regarding study of textile
fabrics, meaning of the word textile must be made quite clear. The dictionary states that the word is
derived from the Latin word texere1 to weave, but a wider meaning of weaving must be accepted
since it is one of the various ways to produce textile fabrics. The initial stage of textile manufacturing
involves the production of the raw material either by farmers who raise cotton, sheep, silkworms, or
flax or by chemists who produce fibre from various basic substances by chemical processes. The
fibre is spun into yarn, which is then converted into fabric in a weaving or knitting mill. After dyeing
and finishing, the woven material is ready for delivery either directly to manufacturer of textile
products where they are finally stitched into clothes.
Polymers are the resource for man-made fibres, which are derived mostly from oil. Plant fibres and
animal fibres constitute the natural fibres. After the fabric is formed, it is generally subjected to
finishing and/or dyeing process, in which the raw fabric properties are modified for the end use.
Methods of fabric formation:
The most commonly used fabric forming methods are weaving, braiding, knitting, felting, tufting and
nonwoven manufacturing. However, major method of fabric construction is weaving.
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Weaving:Weaving is the interlacing of warp and filling yarns perpendicular to each other. There are practically
an endless number of ways of interlacing warp and filling yarns. Each different way results a
different fabric structure. Approximately 70% of the fabrics made in the world are woven fabrics.
Below is the diagram of woven fabrics.
Woven fabrics
Braiding:Braiding is probably the simplest way of fabric formation. A braided fabric is formed by diagonal
interlacing of yarns. Although there are two sets of yarns involved in the process, these are not
termed as warps and fillings as in the case of woven fabrics. Each set of yarns moves in an opposite
direction. Braiding does not require shedding, filling insertion, and beat up. Below is the diagram of
braded fabrics.
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Braided fabrics
Knitting:Knitting refers to interloping of one yarn system into vertical columns and horizontal rows of loops
called wales and courses, respectively. There are two main types of knitting: weft knitting and warp
knitting.
Tufting:Tufting is the process of manufacturing some categories of carpets and similar structures. In this
process surface yarn system of loops is 'sewn' or 'stitched' through a primary backing fabric, usually
a woven or nonwoven fabric. The loops are arranged in vertical columns (rows) and horizontal lines
(stitches). Loops can be in the form of cut or uncut loops (piles) or a combination of thereof. The
fabric is usually back-coated in a later process to secure tufted loops. Orientation of tuffed loops is
shown in Figure below.
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Tuffed loop
Bonding:Bonding is the method of manufacturing nonwovens using textile, paper, extrusion, or combination
of these technologies, to form and bond polymers, fibres, filaments, yarns or combination sheets into
a flexible, porous structure. In fact, some nonwoven products are subjected to both textile and paper
industry. Figure below shows the bonding of nonwoven fabric.
Bonding of nonwoven fabric
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Weaving:-
Introduction to Weaving:
The technique of fabric forming probably became known to mankind before spinning. Primitive
people may have observed the interlaced grasses and twigs in the nests of birds and thus discovered
the way to make clothing for themselves, baskets and nets, thatch like huts and fences using such
materials as grass, leaves, twig, branches etc. Spinning developed later when people discovered that
the raw material could be improved before they were woven. In course of time, rude looms were
made, which were crudely simple and hand operated. The modern looms used in the textile industry
today essentially performs the same operations as the simple hand operated loom (but in much
sophisticated manner). Weaving process contains these steps warping, sizing and final weaving. The
flow diagram of weaving process is shown in Figure below:
Flow diagram weaving process
Warping:This process is also known as beaming. A beam contains large number of individual threads parallel
to each other. The resulting package is a warper's beam.
Sizing:It is the heart of weaving. In the sizing process, coating of a starch based adhesive is applied to the
sheet of yarn to improve its weavability. Sizing increases yarn strength, reduces hairiness, which
minimize the abrasion that occur between the warp thread and various parts of the loom.
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Cone/cheese warping[ Warper's beam]
Sizing [weaver'sbeam]
[Warper's beam]
Weaving [clothroller beam]
[Weavers' beam]
Weaving:A woven cloth consists of two sets of yarns namely warp and weft. The yarns that are placed
lengthwise or parallel to the selvedge of the cloth are called warp yarn and the yarns that run
crosswise are called weft yarns. Each thread in the weft is called a pick.
Basic motions of weaving:Every loom requires three primary motion to produce woven fabric.
1. Shedding:This process refers to separate the warp threads into two layers. One layer is raised and other
lowered.
2. Picking:This process refers to insert a weft thread across the warp ends through the shed.
3. Beat-up:This process refers to push the weft thread that has been inserted across the warp ends up to the cloth
fell.
Secondary motions: Besides the three main basic motions in weaving, there are other two
subsidiary motions necessary for continuous weaving which are termed as secondary motion-
1) Take Up:This is the motion to pull the cloth forward after the beat-up of weft, maintaining the same pick
density and spacing throughout weaving of a cloth and winding the woven cloth on to a roller.
2) Let-off:This motion allows the warp to unwind from the warp beam during weaving and also maintain an
average constant tension of warp as it weaves down.
Auxiliary motions: In order to produce a good quality of cloth and to prevent damages, it is
necessary to have some stop motions provided on the loom which are termed as auxiliary motions-
I. Warp Protector:This motion protect the warp threads by stopping the loom when the shuttle fails to reach, the
selvedge side and box properly into either the shuttle box during picking.
II. Warp Stop:This auxiliary motion to able to stop the loom when a warp thread breaks or get excessively
loosened.
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III. Weft Stop:This motion able to stop the loom when a weft breaks or the weft runs out of the pirn (weft package).
IV. Temple:This motion holds the cloth firmly at the fell to assist the formation of a uniform width cloth.
Types of loom:Weaving of yarn into a fabric is performed on a weaving machine which has also been called a loom.
Looms can be classified in two categories: Shuttle loom and Shuttleless loom.
Shuttle Loom:There are mainly four types of shuttle looms:
Hand loom,
Non-automatic power looms,
Automatic power loom,
Circular loom.
In shuttle looms, winding of weft yarn on pirns and picking and checking of shuttle, which carries
the pirns, are common feature, which limits the speed of the looms.
Disadvantages of shuttle loom are as follows:
Smaller weft package, that require frequent replenishment.
Limited scope for increase in speed and performance.
Noise and performance.
Space and workers required for weft pirn winding.
Complicated mechanism on Multi-colour loom.
Shuttleless Loom:Shuttleless looms can be classified in six major groups:
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Projectile Weaving:
This machine contains a bullet like shuttle, which is 90 mm long and weighs 40 g, technically termed
as gripper projectile, which draws the weft thread into the warp shed from a large, stationary cross-
wound package always from the same side.
Features of Projectile Weaving Machine:
The gripper projectile are made from fine steel, 90 mm long, 14 mm wide and 6 mm
thickness, weighs 40 g.
The weft is drawn directly from a large, stationary cross wound package, where as weft
winding is absent.
During its flights through the shed, the projectile runs in a rake like steel guide, so that warp
threads are touched neither by the projectile nor weft threads.
Weft insertion rate ranges from 900 m/min to 1500 m/min.
Sulzer projectile weaving machine available in two four colour versions with working width
of 190 cm to 390 cm.
The upgraded version of machine is P7200 where as the model P7100 is with central
microprocessor control.
On P7200 model, weft insertion rate is 1500 mpm (3.92 m x 400 rpm)
Rapier Weaving:
Rapier weaving machine produces versatile range of fabrics from outerwear fabrics to sophisticated
label weaves.
Rapier looms are classified as follows:
Single Rapier:
The weft is inserted during rapier insertion, and the weft put in the shed during rapier insertion.
Advantage:
Problem of weft transfer does not arise and normal range of fabric can be woven.
Disadvantage:
One movement of rapier is wasted.
Loom speed is very slow. The maximum weft insertion rate is 400 m/min.
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Double Rapier:(i) These looms work on bilateral principle of rapier insertion. Two rapiers are used for insertion of a
full pick in each shed. Both the rapiers enter simultaneously in the same shed from opposite ends-one
from the giver end with a weft thread and other from the taker end in empty condition.
(ii) The weft is transferred from the giver to the taker.
Weft Insertion Principle: Loop Transfer Gabler System:
The weft is taken by the giver rapier from supply package in loop form.
Tip Transfer Dewas System:
The end of weft is directly transferred from one side of the rapier to the other side at the time of
proper shed opening.
Air-jet Weaving:Weft Insertion by means of airjet has made a major breakthrough in the early 70s and its importance
is increasing further being of its ability to weave a wide range of fabrics at a very high weft insertion
rate of about 2000 m/min. The width restriction is about 150 cm for a single jet with confuser can be
overcomed by a relay jet principle.
Different systems of air-jet weaving are as follows:
Single nozzle with confuser type guide.
Multiple nozzle with guide.
Multiple nozzle with profile reed.
The most commonly used air jet weaving process is the multiple nozzle with profile read.
Water Jet Weaving:Water jet weaving machine has limitation, since only hydrophobic (water-insensitive) yarns can be
woven. But these machines have been successful in the filament area as it is a low cost machine with
low level of energy consumption, characterised with simple maintenance feature.
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Multi-phase Weaving:Within the last decade, Sulzer textile has developed a new multi-phase weaving machine called
M8300 multi linear shed. M8300 is a multiphase air-jet weaving machine in which four picks are
inserted simultaneously. It has a filling insertion rate of over 5000 m/min.
Single phase air-jet loom having 190 cm width typically weaves 23 m of fabric/h. However, M8300
multi-phase loom produces 69 m of fabric for the same width during the same time.
Triaxial Weaving:In this machine, two warp and one weft yarn systems are interwoven at an angle of 60°. The two
warp yarn systems are taken from series of (six) rotating warp beam located above the weaving
machine. The result is interlacing of warp yarn at an angle of 60°. After leaving the warp beams, the
warp ends are separated into two layers and brought vertically down into interlacing zone. The weft
is inserted by two rigid rapier with tip transfer at the centre of shed.
Development of equipment to produce biaxially woven fabric is done by Barbar Colman Company,
USA.
Circular Weaving:Circular weaving machines are not frequent in the textile industry due to the lack of flexibility in the
fabric width and narrow range of options. Only sacks and tubes are woven on circular weaving
machines. In this machine, weft revolves in a circular path.
INFERENCES-Textile materials are of interest to everyone, which play the most important part in human
civilization. As a result, today there are wide variety of textile materials pertaining to wide
application, further improvements can also be anticipated perhaps at a rate, greater than ever before.
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LITERATURE
Weaving with Air Jet
Abstract: In the field of industry, there are only a very few examples of material transport with air
jet, and one of these is the air jet loom. In this weaving technology, the weft (the transversal yarn of
the fabric) is shot by air jet.
Description of Air Jet Looms:In air-jet looms, the weft is introduced into the shed opening by air flow.
The energy resulting from air pressure is converted into kinetic energy in the nozzle. The air leaving
from the nozzle transfers its pulse to stationary air and slows down.
To this end, in order to achieve a larger rib width, V. Svaty developed in 1947 a confuser, which
maintains air velocity in the shooting line.
The confuser drop wires are profiles narrowing in the direction of shoot, and they are of nearly
circular cross section open at the top. These drop wires are fitted one behind the other as densely as
possible. Therefore, they prevent in the shooting line the dispersion of air jet generated by the nozzle.
The Figure below shows the arrangement and design of the confuser drop wires applied in machines
of the P type, as well as the arrangement schematic of weft intake. The nozzle is secured to the
machine frame, and the confuser drop wires and the suction pipe are fixed to the loose reed.
The confuser drop wires are profiles narrowing in the flow direction, and they have a conicity of 6°.
These profiles may be made of metal or plastic.
To be considered almost as a closed ring from the aspect of flow, a baffle plate of nearly circular
cross section is placed on top of the latter.
In the top part – in comparison with the metal confuser – they substantially reduce the air outflow,
and therefore the reduction of air jet velocity will be smaller in the direction of shoot in the confuser
drop wires.
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The slay is oscillated by a specific drive mechanism, to make sure that during the shoot, the swinging
motion of confuser drop wires does not possibly influence the conditions of flow. This is because in
case the displacement of the confuser drop wires is large during the shoot, the air flow conditions are
unfavourable from the aspect of introducing the weft into the shed, and hence the warps may reach
into the inner space of the confuser.
Arrangement and design of the confuser drop wires applied in a type P machinea) metal confuser and its fixing b) plastic confuser
In a type P machine, the nozzle is secured to the machine frame, while the confuser drop wires swing
with the rib.
During the shoot, the nearly stationary position of the slay is ensured by an eccentric articulated
movement. In machine P 165 mentioned as an example, the introduction of the weft is carried out in
0.08 sec, four times in a second.
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Movement of the confuser drop wires
By the application of the confuser drop wires, a rib width of b=165 cm was achieved. This is where
the name of loom type P 165 comes from. The confuser drop wires cover 75 to 85% of the rib width.
The design of the loom nozzle is shown in Figure below, indicating the velocity patterns of the air
leaving the nozzle, in addition to the weft.
Velocity distributions evolving in the nozzle
In front of the nozzle there is a yarn box, the function of which is to store one shoot of yarn. The box
is designed in a way that the yarn can be removed from it almost without resistance.
One type of these boxes is the pneumatic yarn box as shown in Figure below:
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Pneumatic yarn box
The pneumatic yarn box has a simple design, and its stores the yarn of specified length in a tube with
a slow airflow, in the form of a loop. For introducing the weft, depending on the structure of the
yarn, compressed air of 1.5 to 3.0 bar pressure is required.
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WARP BREAKAGES
INTRODUCTION:
Warp breakages are major cause of stoppages in the looms. Stoppages due to warp breakage result in reduced efficiency and productivity. The time taken to mend a warp break is comparatively higher than the weft. Not only this entails that there is increase in work load for the weaver but it also increases the manpower requirements with each weaver managing less no of looms due to these breakages. Therefore reduction of warp breakages is of prime importance to any industry.
During the process of weaving, the warp yarn is subjected to a complex action consisting of extension, abrasion and bending. Locations of these actions are shown in the table below.
These forces act together on warp yarn resulting in complex force field on warp yarn. It is not easy to define any mathematical equation to quantify the effect of all these forces.
Preparatory section also plays a very important role in the strength of warp yarns. Apart from yarn parameters sizing is also very important process with respect to warp breakages.
The sized yarn consist of two elements i.e. yarn and the size film which have different extensions under mechanical stresses.
The main causes of warp breakages during weaving are due to following:
Faults occurring in warping zone. Faults occurring in the sizing zone. Faults occurring in the weaving zone.
FAULTS OCCURING IN WARPING –These are mostly related to yarn quality.
Faults Causes Weak yarns Slippage of drive belt from wharve wheel
Reduction in spindle speed and thus reduction in tpi.
Improper functioning of the ring frame.
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Loom Action LocationFlex abrasion Back roller, healds, dropwires and fell of cloth.
Scraping action Any part where yarn contacts moving parts.Yarn to yarn abrasion, cyclic stretching, bending
and entanglementHealds and reed motion.
High percentage of short fibres in yarn raw material.
Cut aprons or breaks in the teeth of ring frame gears.
Thin place Non uniform draft in the drafting zone. Faulty ring frame. High percentage of short fibres or
drafting wave. Thick places or slubs Thin place is generally followed by a
thick place. Reasons are same as that of thin place. Fly and fluff gets caught during yarn
spinning leading to formation of slubs. Extra yarn Suction system in the winding zone not
working properly. Cut cones Broken ends in the cones. Improper splicing Improper length of yarn taken for
splicing. Twist per inch given to the yarn is
different. Variability in the cone weight Large variation in package weight results
in some package finishing before others. Slough off Improper winding of the package.
Inappropriate package hardness. Defective cones Damage to the cone during transport Slip knot or skip splice Knot slips and unfolds during warping.
Low surface friction of yarn. Knotting not done tightly.
Slubs or thick yarns More loose fly in mill. Twistless yarns or improper twist in the
yarn. Thin yarn More tension is applied in the spinning
zone. Fibre slippage in the spinning zone.
Hairiness Always more in unsized yarn. Improper twisting of fibers. More amount of short fibers during
mixing. Excess abrasion of yarn with guides
during winding. Inappropriate twist Due to faulty ring frame setting. Piecing up of yarn Not having found the tail of the package.
To tie the yarn from any other broken yarn coil on the winding package.
Sometimes the operator doesnot tie the yarn end but merely winds the yarn on the package.
Missing end Mainly due to faulty stop motions. Machine unable to detect the breakage.
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Yarn breaks due to dead weight , tension variations and yarn problems.
FAULTS IN SIZING SECTION-
Faults Causes Fluctuating warp tension Warp tension incorrectly set or faulty
load cell in sizing m/c. The drive chain has insufficient tension,
the warp sheet is non uniformly stretched. One or more of the drying cylinders are
defective Improper shape of the drying cylinders.
Warp sheet adhering to the drying cylinders or the guide rollers.
Teflon coating on the guide rollers and cylinders is damaged.
The temperature of the drying cylinder is too low.
Tacky warp yarns Excessive sizing of the warp sheet due to nip pressure being too low.
Excessive size liquor concentration. Faulty sizing due high viscosity of the
sizing paste. Sticky ends Different degree of sizing at different
places Incorrect drawing of threads through
lease rods. Roller licking Broken end adhering to the rollers and
winding around it. Size liquor too viscous. Faulty load cell and roller pressure.
Increased warp neppiness The rubber coverings on the squeeze rollers are defective.
Formation of bands and gaps in the warp sheet.
Warp tension in size box too low. The immersion roller not bearing on the
bottom roller. Pressure variations.
Different degree of sizing across the width.
Squeeze rollers have non uniform nip pressure because of variation in rubber hardness , roll diameter and roll shape.
Difference in warp tension due to different beam diameters.
FAULTS IN WEAVING SECTION-
Faults Causes
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Missing ends Defective mending in the warping and sizing process.
Cross ends High winding tension. Tension variation in individual ends
End migration Improper drawing of warp beam layers. Improper drawing over lease rods. Improper mending of broken ends.
Sticky ends More amount of size material accumulated.
Hardness of squeeze roller is less. Buffing action of rollers. Immersion roller depth. Sizing m/c is working but steamer of the
m/c is off, wet beam is formed. Hairiness resulting in yarn entanglement. Improper twist in the yarn during
spinning. More amount of short fibres during
mixing. Excess abrasion of yarn with the guides.
High fly generation in shuttle-less looms. Looms operate at very high speeds. More abrasion of yarn at higher speed
and with heald frames and also yarn to yarn abrasion.
Fly formation due to sharp edges and rusting of drop pins.
PARAMETERS:
Before beginning with the study to reduce warp breakages , the parameters associated were identified. They were divided into 4 categories-
1) Yarn parameters.2) Warping parameters.3) Sizing parameters.4) Loom parameters.
Each of these parameters has direct bearing on the warp performance in loom shed.
1) YARN PARAMETERS:
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Parameters Effect Count Lower the count, higher is the breaking
strength of the yarn, but lower tenacity. RKm Higher the rKm, higher is the breaking
strength of the yarn. Min rkm The yarn always breaks from the place
having lowest rkm, thus min rkm>9 for smooth operation. Higher min rkm, better the yarn performance of the loom.
Rkm cv% Lower the variation in rkm, better the performance on the loom.
Elongation Higher the elongation, better the performance of the yarn on the loom.
Elongation cv% Lower the elongation cv% , better the performance of yarn.
Twist multiplier , T.M. It plays important role in the strength of the yarn, it must be optimized.
Hairiness Hairiness must be optimised since lower hairiness would in increased production cost due to higher air pressure. Higher hairiness would also result in problem of flying weft due to very high air drag force.
Uster% Determines the quality of yarn according to standards set by Uster. Lower the Uster% better the performance.
Thin places , thick places , neps They should be as low as possible
2) WARPING PARAMETERS:
PARAMETERS EFFECTS Breakage/100000m More the no. of breakages , more the
chance of yarn abrasion from the press roll, thus more chances of breakages.
Tension in each thread Positive control over the creel tension upto the tension of 400m/min. , the creel tension then reduces to zero. The tension then is only due to the dead weight of the yarn. Tension in each thread should be uniform, otherwise zig – zag shaped package will be formed with varying tightness, high breakage in sizing section.
Warping beam hardness ( Density) Needs to be optimized. Loosely wound package may result in high breakage in sizing zone, whereas if we increase the
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package hardness, either the speed or tension need to be increased which would result in high warp breakages in warping zone ( when the loosely wound part would be unwounded).
Slough off Results in high breakage Distance between flanges (D.B.F.) Must be fixed. Stop motions The stop motions need to be working
properly in order to avoid missing ends. Missing ends result in multiple breakages in loom shed.
Yarn quality Yarn quality has huge bearing on overall performance and efficiency of the process.
3) SIZING PARAMETERS:
PARAMETERS EFFECTS Alignment of the creel Must be properly aligned Beam tension in sizing creel Must be equal for uniformity in the
weaver’s beam, otherwise zig – zag package with non uniform density will be formed increasing the warp breakages.
Preparation of sizing paste Paste must be prepared in appropriate concentration, using excess or insufficient size would result in breakages.
Viscosity of the sizing paste It should be appropriate for correct size penetration and pick up.
Temperature of the drying zone Excess or insufficient moisture would result in increased breakage.
Stretch Lower the stretch better the performance on the loom. Ideally there should be no stretch in the warp yarns.
Leasing zone The sheet should separate appropriately in the leasing zone otherwise might result in sticky ends or crossing or end migration.
Temperature of the size box Needs to maintained for appropriate viscosity.
Denting calculation Needs to be done according to the end density ( Ends/cm)
Angle of the sheet Should be less than 80 degrees. D.B.F. D.B.F. varies according to the size of
the towel being prepared, different size require different D.B.F. being used even for the same width.
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Hardness of the packages Harder the package better would be performance on the loom. Pile is comparatively loose wound.
Winding roller tension Has bearing on stretch alone, higher the value, more will bee stretch.
Press roller tension It determines the beam density, higher the value more dense the beam.
Moisture in the warp It is very important factor, directly related to the strength of the yarn in the loom shed. It should be optimizid for best results.
Note: The machine speed in the sizing is determined by both, moisture required in the warp yarns and the temperature of the drying cylinder. It should be set accordingly. Suppose the temperature of the drying drum is low then the machine would operate at lower speed so that desired level of drying can be achieved. Similarly if moisture required in the yarn is higher then m/c would operate at higher speed so that warp is not in contact with the drying cylinder for a long time.
4) LOOM PARAMETRES: Effect of individual loom parameters on warp breaks is very complex, thus they have been classified as under-
Abrasion:-i. Condition of drop pins
ii. Condition of heald wires.iii. Condition of reed.iv. Yarn to yarn abrasion.
Cyclic stresses:-i. Force of beat up.
ii. Cloth fell distance.iii. Fell plate height.iv. Frame height ( Dobby notch setting)v. Crossing angle.
vi. Terry bed motion.vii. Rpm of the loom.
Bending:-i. At the beam during let off.
ii. Tension roller.iii. Shed angle.iv. Height of back roller and dropper.
Construction:-i. Picks/cm
ii. Pile height.iii. Cover factor.
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iv. Weave/design. Environmental factors:-
i. Temperature of the loom shed.ii. RH of the loom shed.
iii. Temperature at the loom.iv. RH at the loom.
Now individual parameters have been discussed below:-
ABRASION:- The abrasion depends on the friction the yarn experiences during its path from weaver’s beam to cloth fell. The yarn path is as follows:-
More friction the yarn experiences, weaker it becomes; resulting in warp breakages. Thus breakage due to abrasion would depend on the condition of the drop pins, heald wires, reed, and also on the friction that yarn offer to each during the shedding.
CYCLIC STRESSES:- Yarn experiences cyclic stresses during shedding and beat up. During shedding, more
is the displacement of yarn from crossing position more would be the stress on the yarn and consequently more warp breakages.
More is the cloth fell plate height, higher would be the cloth fell, more will be the pile height. These affect the cyclic stresses. The relationship is complex and not clearly defined.
More is the dobby notch setting ,lower would be the frame height and lower stress on warp hence lower would be the breakages. Inadequate frame height would lead to weft entanglement inside the shed and increase the breakages.
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BEAM TENSION ROLLER
DROP PINS
HEALD WIRES
REEDCLOTH FELL
Terry bed motion should be set according to the warp tension. If it is not then it would lead to warp breakages.
More is the RPM of the machine, more is the breakages as cyclic stress would increase in frequency.
More is the force of beat up, more would be the chances of warp breakages. If the force of beat is too high, it would into smashing of yarn at the cloth fell. Angle of crossing is also an important parameter, more is the angle of crossing easier is the weft insertion.
BENDING:-Any bending consists of two kinds of forces:-
a) Tensile forces.b) Compressive forces.
Whenever the yarn is wrapped around any roller it would bending which is both compressive and tensile. The yarn also bends around the heald eye, thus shed angle is also a parameter. The height of back roller also plays a significant role in determining tension in warp yarns.
CONSRUCTIONS:- Pile height increases the no. of warp breakages. Increasing cover factor would again increase the bumping thereby increasing the warp
breakages. Design also has a significant effect on warp breakages, with the design having pleated
borders would have more breakages. Knot slipping and entanglements also contribute to warp breakages.
ENVIRONMENTAL FACTORS:-The loom RH and temperature must be maintained. The standard RH and temperature for looms are 80% RH and 30 degree temperatureThe loom shed must be maintained at 65% RH.
SOME TYPICAL LOOM SETTINGS:-Below is the list of some typical loom settings which can be easily varied on the loom with their correlation with warp breakages.
Height of the back roller and dropper.As the back roller and dropper lift up, the tension of the centre sheds will increase and that of open shed warp will decrease. This will affect the warp breakages.
Heald frame height.Lower the heald frame lower would be the tension in the warp thus higher heald frame height would lead to higher breakages.
Shed size ( Heald frame stroke).The larger the shed size, the easier becomes picking; the smaller, the more difficult the picking. The more difficult the picking, more would be the warp breakages.
Shed close timing.
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The earlier the shed close timing, the easier the picking; the latter, the more difficult. The easier the picking, lower will be the no. of warp breakages.
Easing timing.Earlier the easing timing , the more difficult the picking, hence more breakages.
Easing amount.For high tension, decrease the easing amount; for lower tension, increase it. Failure to do so would result in increased warp breakages.
Height of cloth fell.The higher the cloth fell, the easier the picking. For higher tension lift up the cloth fell; for lower tension, lower it.
Analysis of warp breaks
BROWN classified the warp breaks under eight headings which are as follows:
1. Knots: 30-35% of the warp breaks during weaving are due to the presence of knots. This is because, firstly the knot may slip or it may break if it fails to pass through the healds, reed etc. Secondly due to the scissoring action of knots, the adjacent warp threads are damaged and breaks are caused by the obstructions resulting from the action of the knots on the yarn that creates abnormal tension in the obstructed threads. The rigidity of protuberance on the yarn increased with the increase in size contact and this increases the possibility of breaks. This type of breakages can be reduced by using spliced joints in place of knots.
2. Breaks due to impurities: Fly which is sized and flattened produces warp breaks by reason of its inability to pass through the reed dent, heald eyes and drop wires or flattened slub becoming involved in the shedding zone. This type of breaks occurs in the shedding zone. This type of breaks occurs in the shedding zone as well as in the back zone.
3. Chopped ends: Chopped ends are considered as such when they occur and reoccur adjacent to beam flanges. Severe treatment of bad handling of the weaver’s beam is the main cause of this type of breakages.
4. Abrasion: These breaks are usually confined to the shedding region with the majority occurring either in the healds or in the front shed. A majority of the abraded breaks particularly undersized are caused at normal peak tension.
5. Soft yarn: Thin or soft places are the region of weakness and some breaks occur at the weak places at the weak places at the normal peak tension without any contribution from abnormal tension or disturbance of the yarn by abrasion.
6. Twisted ends: In this case two ends are twisted together tightly and compactly and considerable effort is required to effect separation. The frequency of occurrence of such fault is very low.
7. Taped ends: Two or more number of ends sticking together also cause warp breaks. This is mainly due to faulty working at sizing.
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DOLECKI classified warp breaks as under:
1. Breaks near lumps on the same thread (LST) i.e. on broken thread: The great majority of such breaks occur in yarn of normal strength owing to some form of obstruction that causes abnormal tensions to occur. Such a tension increase may be caused by a lump failing to pass freely through the drop wire, or reed dent. In addition some LST breaks occur in back zone of the loom at the points of abnormal weakness associated with lumps under the normal peak tension.
2. Breaks near lumps on the other thread (LOT) or nearby unbroken threads whose locations were recorded: These breaks are caused by obstruction resulting from lumps on the yarn that creat abnormal tension in the obstructed threads.
3. Breaks due to other causes (OC): These breaks are further classified as rubbed breaks characterized by disturbance and slippage of fibres, tension breaks- distinguished by a clean break at which nearly all fibres are broken and the yarn is of normal thickness and thin places breaks- those that occured at places at which the yarn diameter is appreciably less than the average.
LOT, LST and tension breaks increased with increasing size content. Rubbed breaks decreased with increasing size content as consequence of increasing
resistance of the yarn to abrasion. The effect of lubrication is to reduce all breaks with the exception of LST breaks at the higher
size content.
MATERIALS AND METHODS
STUDY REGARDING YARN PROPERTIES
Following yarn study was performed on USTER TENSOJET-4--
Date Lot no. Count Supplier RKm Min RKm Elongation21/6/12 12NRZX27 1/12KW Nandan 19.13 14.40 5.422/6/12 524 1/12KW TC 19.97 14.81 5.71
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22/6/12 1206 1/12KW Bhaskar 18.99 13.46 6.0722/6/12 525 1/12KW Satia 19.31 14.63 5.5329/6/12 124120308 1/12KW Ty 4 13.65 9.58 5.7429/6/12 921412010 1/12KW Oswal 16.82 12.44 4.242/7/12 2121294 1/12KW Vallabh 20.13 14.63 5.362/7/12 SAMPLE 1/12KW Sangam 19.62 14.73 6.493/7/12 121212038 1/12KW Ty 1 19.06 14.10 5.584/7/12 124212425 1/12KW Ty 4 19.11 15.10 4.8810/7/12 121212040 1/12KW Ty 1 19.31 14.63 5.5714/6/12 22422 2/24KW Punjab 18.10 12.83 4.219/7/12 125124A81 2/24KW Ty 5 21.84 16.26 4.3312/7/12 242101 2/24KW Pratap 19.34 13.69 4.7914/7/12 7122224037 2/24KW Nahar 20.63 15.10 5.1827/6/12 22057 2/20KW Punjab 18.35 13.63 4.529/6/12 124120308 2/20KW Ty 4 13.65 9.58 5.746/7/12 Spintex 2/20KW Punjab 18.38 13.76 4.610/7/12 411220455 2/20KW Nahar 15.36 10.76 4.8213/7/12 123210862 1/10OE TY 3 12.99 8.28 5.914/6/12 124126316 2/26CW TY 4 13.03 10.25 5.079/7/12 1222602 2/26CW Nahar 14.59 10.47 5.2613/7/12 A11232811 2/26CW Maral 23.13 14.24 7.683/7/12 122116524 2/16CW TY 2 18.16 12.42 4.697/7/12 21602 2/16CW Punjab 22.14 18.21 5.0514/7/12 1221216001 2/16CW Avani 20.27 16.12 5.264/7/12 Rung.lot 1/12CW Mahima 21.92 11.8 6.864/7/12 124112415 1/12CW TY 4 19.10 14.48 5.3321/6/12 18Airrich 2/18CW TY 17.24 10.54 4.91
Inferences:- a) Since the yarn having higher rkm, higher min rkm,and higher elongation provide
better weavability, thus the yarn must be taken from those vendors/suppliers which provide better properties.
b) The 1/12KW yarn made of Trident is inferior in above mentioned properties as compared to Vallabh and Sangam. It is prone to high warp breakages.
c) The 2/24KW yarn of Nahar provides better weavability as compared to Pratap, Punjab and Trident yarn..
d) The 2/20KW yarn of Nahar and Punjab have better properties than the Trident yarn, thus 2/20KW yarn must be taken from these vendors.
e) For 2/16CW yarn Avani and Punjab are preferred.f) The 2/26CW yarn of Maral is better than that of Nahar and Trident in terms of rkm,
min rkm and elongation, thus it must be preferred.
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STUDY OF LOOM SHED
WHY-WHY ANALYSIS
A why-why analysis was done to identify and solve the reasons of following types of warp breakages—
False breakages. Multiple breakages in warp sheet Breakages due to improper loom settings. Breakages after knotting.
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False breakages:-
Causes Solutions Why(1) Drop pins touches continuously.
False breakage at serrated ends. Knotting pass should
be done by passing knots by pulling after loosening the sheet
Why(2) Bent drop pins. Insulation gap is less.
Why(3) Drop pins bent at time of knotting pass. Worn out plastic insulation sheet.
Why(4) Knotting pass in running condition. Life cycle of plastic sheet completed.
Multiple breakages in warp sheet:-
Causes Solutions Why(1) Warp breaks but machine running. Checking of adopter
for proper tightening. Checking stop motion
wire for proper tightening.
Standard setting display in gemba.
Why(2) Warp stop motion adopter is loose. Stop motion wire is loose. Dropper settings not as per standards.
Why(3) Stop motion adopter loosely tightened. Clamping of wire with adopter is loose. Feed of wrong dropper settings when
problem occurs.Why(4) Loosening and tightening at time of
changeover. Loose wire clamping. Lack of knowledge.
Why(5) Size change. Loosening and tightening of adopter with
every change over in loom
Breaks due to improper loom settings:-
Causes SolutionsWhy(1) Breakage at beating.
Breakage in shedding zone. Breakage before shedding zone. Breakage at separators.
Info. for high pile ratio quality at time planning of loom in log book.
Checking loom after start of new quality and quality sheet should be prepared.
Checking of change of ground beam tension as per
Why(2) Abrupt pressure on warp sheet. Wrong frame and dobby knotch setting. Higher ground tension than required. Warp sheet rubs near separators.
Why(3) Reed touches with beating point for longer time.
Frame height and dobby knotch setting not as
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per quality. Tension not set after quality change. Non parallel separator settings.
quality. Alignment of
separators after beam change.
Alignment of separators after change over loom.
Why(4) Fell plate height is low especially in high pile ratio quality.
Lack of knowledge. Separators not aligned after knotting. Separators not aligned after changeover.
Why(5) Fell plate height not as per quality. Beam change. Quality change.
Breakage after knotting:-
Causes SolutionsWhy(1) Warp yarns cross over
adjoining ends near drop wires.
Cross knotting. Dressing not parallel. Brush application at sheet
is above frame.
Application of brush from dropper bar.
Why(2) Cross ends after knotting. Less ends in between the
towels and extra ends at sides.
Selvedge and body ends not separated before framing.
Separation of body and selvedge ends at time of framing and counting of threads after knotting.
Why(3) Multiple breakages. Broken yarn entangles
with running warp sheet. Machine is running at time
thread is broken. Dropper is missing.
Checking of threads to ensure dropper on each thread.
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Why(4) Warp sheet is cross. Warp sheet cross on
frame. Warp sheet crosses when
taken on frame. No positive control over
complete sheet.
Double tap application on beams with 1/10OE yarn.
Why(5) Crossing at small areas of cross sheet.
Crossing at time of reed application.
Gap between reed dents is more
Reed dents are bent.
Straightening of bent dents to maintain proper gap in the reed dents.
STUDY OF LOOM PARAMETERS
METHODOLOGY:-
1. Study was conducted to find out worst performing loom.2. These looms were observed and samples of various kinds of breakages were collected.3. The worst performing qualities were chosen for experimentation so that if there is failure
in experiment, the production is not affected.4. Various crossing angles, tensions, fell plate distances were measured.5. It was supposed that increasing the fell plate height could reduce number of warp
breakages.6. It was also proposed that the delay in crossing would further help in improving
performance of the loom as it will lower the weft breakages. 7. New data was compared with the previous data from conventional loom settings. Marked
improvement was found in warp breakages.8. The new settings were tried on other looms to check the reproducibility of the results.9. Various variations were done to enhance the results and reproducibility.10. Positive results were obtained.
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WORST PERFORMING LOOMS (LOOMS WITH MAX. BREAKAGES):- To identify the causes of breakages it was decided to observe the worst performing looms. Various machine and material parameters that were recorded are as-
1. Loom no.2. Type ( pile/ground)3. Quality4. Yarn vendor5. Yarn count6. Tensions7. Cloth fell plate height8. Frame height9. TG code.
Worst performing looms on 31/7/2012:-
Loom no.
Type Tg code
Quality Yarn vendor
Count Tensions Fell plate
height
Frame height
30 Pile 3766 Walmart TFO 2/16LT P=110G=450
6 G=100P=105
114 Pile 3766 Walmart TFO 2/16LT P=100G=410
6 G=100P=105
86 Pile 3766 Walmart TFO 2/16LT P=120G=390
6 G=100P=105
111 Pile 3742 Ralph Rewinded 1/12C P=120G=470
6 G=100P=105
41 Pile 3760 Target TFO 2/21C P=120G=400
6 G=100P=105
134 Pile 4163 Sam’s TFO 2/16C P=100G=440
6 G=100P=105
45 Pile 3694 IKEA ABIL 1/16C P=110G=450
6 G=100P=105
137 Pile 4180 Macy ABIL 2/26 P=90G=420
6 G=100P=105
126 Pile 4180 Macy ABIL 2/26C P=80G=380
6 G=100P=105
25 Pile 3693 IKEA ABIL 1/16C P=100G=420
6 G=100P=105
152 Pile 4180 Macy ABIL 2/26C P=100G=470
6 G=100P=105
187 Ground
3692 IKEA Pratap 2/24K P=120G=470
6 G=100P=105
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83 Ground
4836 Walmart ABIL 1/10OE P=110G=420
6 G=100P=105
16 Ground
3997 JCP Nahar 2/20K P=110G=480
6 G=100P=105
73 Ground
3760 Target Avani 2/20K P=90G=380
6 G=100P=105
57 Ground
3742 Ralph Avani 2/20K P=100G=350
6 G=100P=105
161 Ground
3692 IKEA Pratap 2/24K P=140G=400
6 G=100P=105
20 Ground
4839 Walmart Nahar 2/24K P=80G=310
6 G=100P=105
111 Ground
3742 Ralph Punja b 2/20K P=120G=470
6 G=100P=105
Frequency of different quality on worst performing looms:-
TG CODE QUALITY TYPE FREQUENCY12003766 Walmart Pile 312003742 Ralph Pile
Ground12
12003760 Target PileGround
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12004163 Sam’s Pile 112003694 IKEA Pile 112004180 Macy Pile 212003693 IKEA Pile 112004839 Walmart Ground 112004836 Walmart Ground 112003692 IKEA Ground 2
Inferences:-1. TFO 2/16 material is showing maximum no. of breakage.2. Since 2/20KW showed most ground breakages, study was concentrated on this count.3. Since only some of the looms running on a particular quality were showing high no. of
breakages it was decided that loom settings should be changed to reduce the no. of breakages rather than focusing on yarn parameters which essentially depend on vendors.
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Causes of improvement in warp breakages due to change in loom settings:-
Change in setting Earlier Present EffectGround tension Random 400 Reduction in warp
breakageFell plate height 6mm 6.5mm Reduction in warp
breakagesTorsion bar setting Random 5.5 Reduction in warp
breakagesAngle of crossing 300 310 Reduction in weft
breakages
1. Fell plate height:- According to measurements it was observed that warp line was not passing exactly to profile of the reed when shed were levelled at the angle of crossing.There are two factors which might be reduced on increasing the height of cloth fell, first there were high cyclic stresses on the warp yarns near the reed which could be reduced in magnitude and secondly the abrasion between warp yarn and reed could be lowered.Also, increasing the fell plate would mean that the beat-up would take place earlier than before. This will lower the force experienced by yarn at the beat-up hence reducing the no. of breakages.Traditionally , higher the cloth fell easier the picking; the lower the more difficult. For higher tensions lift up the cloth fell; for lower tension lower it. Failure to do above would result in higher weft breakages. A trial was taken on this fact.Methodology:-
The loom with high no. of breakages was selected for trial so as to minimize the risk of loss in production.
The height of fell plate was increased from 6mm to 6.5mm. The problem of weft entanglement was observed. It was due to change in angle of insertion of weft and shape of the shed. Thus the angle of crossing was changed to 310degrees. The weft entanglement stopped. It was decided that the ground beam tension should be varied to see any improvement
in breakages. The torsion rod was set according to the beam tension.
2. Angle of crossing:- Increasing the fell plate height increased the number of weft entanglements in the shed while closing lead to increased weft breakages.It was reasoned that increasing the angle of crossing would help in solving the problem as the increase in cloth fell plate changed the shape of the shed.Increasing the angle of crossing changed the angle of insertion of weft relative to the shed and allows the weft to pass without entanglement in new shed shape ( which is due to increased fell plate height).
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3. Decreasing the tension in ground beam:- Increasing the fell plate height would result in increase in force on the towel at cloth fell. Thus the cloth fell must be flexible. Thus the warp yarn tension in the ground beam was reduced which automatically results in reduced warp breakages. Various tension settings were tested. There is a weak correlation between tension and warp breakages as the breakage don’t change in range of 380-420kgf.
4. Setting of torsion bar:- It was found that torsion bar setting varied randomly on the looms. It was decided to standardize and fix it corresponding to tension on ground beam. Each division of torsion rod corresponds approximately to 70kgf of tension in ground beam.Thus,Tension in ground beam—400kgfTension corresponding to one division—70kgfNumber of divisions required—400/70 = 5.55Since the least count of the scale was 0.5 it was decided to fix the torsion bar setting at 5.6
The loom 57 was selected for performing the trials, tables present the brief summary of the experiment,
DATE PILE BREAKS/CMPX GROUND BREAKS/CMPX
2012.08.08.A 20.88 6.142012.08.08.B 16.28 13.952012.08.08.C 10.64 5.82012.08.09.A 15.83 13.972012.08.09.B 12.60 18.332012.08.09.C 20.90 10.452012.08.10.A 18.11 11.142012.08.10.B 17.39 13.042012.08.10.C 8.23 6.97
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2012.08.11.A 0.00 1.022012.08.11.B 3.13 1.562012.08.11.C 3.89 3.892012.08.12.A 2.95 7.362012.08.12.B 1.42 2.232012.08.12.C 1.06 4.232012.08.13.A 1.23 3.692012.08.13.B 1.13 0.562012.08.13.C 0.00 1.562012.08.14.A 1.38 2.072012.08.14.B 1.77 1.18
CONCLUSIONS
1. A marked reduction in breakages was observed.2. Both pile and ground breakages were reduced.
COST ANALYSIS
Average pile and ground breaks/cmpx before 18/06/2012 = 3.856 + 3.817 Average pile and ground breaks/cmpx before 14/06/2012 = 3.739 + 3.707 Reduction in pile and ground breaks/cmpx = ( 3.856-3.739 ) + ( 3.817-3.707 )
= 0.117 + 0.1097 = 0.2265 breaks/cmpx/loom/day
Average total CMPX per day = 1050 cmpx Thus , total reduction in breaks/cmpx per day = 0.2265*1050
= 237.825 Average time of mending one break = 2 min. Thus , total time saved per day = 2*237.825/60
= 7.9275 hrs. Average production by 1 loom in 24 hrs = 350 kgs Thus , total production savings per day = 350/24*7.9275
= 115.6 kgs/day Now , conversion cost of material = Rs. 30/kg
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Thus , total financial savings per day = 115.6*30 = Rs. 3468.28/ day
So, total financial savings per month = 30*3468.28 = Rs. 1,04,048
Thus total savings in 1 year = 12*104048 = Rs. 12,48,576/annum.
FUTURE SCOPE
There are two issues regarding future scope of this project:-
1. Are the settings reproducible on other looms as well?2. What are the parameters which decide whether these settings are reproducible or not?
The answer is yes, these settings are completely reproducible because the breakages have been reduce on account of increased cloth fell and angle of crossing. These parameters are equally important for every quality. Other factors like GSM and design have no drastic changes.
REFERENCES
1. WEVING – TALUKDAR& AJGAONKAR.2. TECHNOLOGY OF WEAVING BY N.N. BANNERJEE
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THANK YOU
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