WEAVING

TRAINING
MANUAL

mayankbindal.com
1) TEXTILE FIBER CLASSIFICATION
 Natural Fibers
 Man-made Fibers

2) FIBRE SPECIFICATIONS AND DEFINITION

i. Length
ii. Strength
iii. Mic/Denier
iv. Moisture content
v. Moisture regain
vi. Cross-section
vii. Dyes selection for particular fibers

mayankbindal.com
3) IMPORTANT YARN CHARACTERSTICS THAT HAVE AN IMPACT ON FABRIC APPEARANCE,
PROPERTIES AND PERFORMANCE LIKE :

3.1 Structure, twist level & direction, bulk, hairiness, fiber characteristics, count, strength, elongation,
diameter, absorbency etc.

3.2 Significance of Blends

3.3 Yarn twist : Twist multiplier, Twist direction

4) YARN NUMBER SYSTEM AND CONVERSION

i. Direct (Tex, Decitex, Denier)
ii. Indirect (English count, Metric count, Worsted count, Woollen count

5) WOVEN FABRIC DESIGN AND CONSTRUCTION

5.1 Woven fabric construction
 Symbolic representation of a weave
 Drawing-in-draft (DID)
 The reed plan
 Can draft or Chain draft (CD)
 Warp and filling profiles

mayankbindal.com
5.2 Basic weave designs
 Plain weave : Rib, Basket weave
 Twill weave
 Satin & Sateen weave

6) WEAVING PREPARATION
6.1 Introduction of winding process

6.2 Warp preparation

 Direct warping
 Indirect warping

6.3 Slashing/Sizing
6.4 Drawing-in
6.5 Tying-in

mayankbindal.com
7) BASIC WEAVING MOTIONS AND CALCULATIONS

7.1) Primary motion

7.1.1 Shedding : Cam shedding, Dobby Shedding, Jacquard Shedding
7.1.2 Picking : Shuttle, Shuttleless
7.1.3 Beating

7.2 Secondary motion : Let-off, Take-up

7.3 Tertiary motion or Stop motions

7.4 Fabric control

 Fabric width
 Selvedge

8) SHUTTLELESS WEAVING

8.1 Rapier filling insertion

8.2 Air jet filling insertion

mayankbindal.com
9) FABRIC STRUCTURE, PROPERTIES AND TESTING

9.1 Fabric properties

 Fabric weight, Thickness
 Crimp
 Fabric cover factor and Density
 Tensile strength
 Tear resistance
 Fabric bow & skew etc.

10) ANTISTATIC/ BINDER OIL IMPORTANCE

11) COMPRESSED AIR QUALITY AND SPECIFICATION
12) BEAM QUALITY
13) WEAVING FABRIC DEFECTS, REASONS AND HOW TO CONTROL THEM
14) WEAVING CALCULATIONS

mayankbindal.com
mayankbindal.com
 POLYESTER

VISCOSE

mayankbindal.com
FLAX/LINEN
Staple length
• The average length of the longer half of the fibers
• Upper-half-mean length
• It influences Spinning limit, Yarn evenness, Handle of the
product, Luster of the product, Yarn hairiness, Productivity
• Aids in cohesion and twisting
• The longer the fiber, the stronger the yarn
• The staple length groupings are currently used in the trade staple are Short staple, Medium staple,
Long staple, Extra long staple
• Synthetic fibers are produced in the form of continuous filaments, which are long, continuous strands of
fiber.
• They can be used in this form but it is usual for them to be cut into predetermined lengths (i.e. staple
fibers) to suit the type of yarn needed.
• Natural and synthetic fibers are often blended together when making yarns (e.g. wool/nylon,
cotton/polyester), giving the benefits of both fiber types.
• For this purpose the length of the synthetic filament may be cut to match that of the natural fiber, thus
making it possible to use the same spinning machinery for both fibers.
•
mayankbindal.com
Strength
• Strength of any material is derived from the load it supports at break and is thus a measure of its
limiting load bearing capacity.
• Individual fibers must have sufficient strength to withstand normal mechanical strain in the processing.
• The resistance of a fiber to use and wear is considerably dependent on its tensile strength..
• Tensile strength of textile fibre is measured as the maximum tensile stress in force per unit cross-
sectional area or per unit linear density, at the time of rupture called „tenacity‟.
• Expressed in terms of grams per denier or grams per tex units.

Micronaire (mic)/den
• Mic is a measure of the air permeability of compressed cotton fibres
• An indication of both fibre fineness (linear density) and maturity (degree of cell wall development)
• Low mic indicate fine or immature fibres
• High mic indicate coarse or mature fibres
• It influences:
 Processing waste
 Neps
 Spinning performance
 Yarn and fabric quality
 Dye-uptake and dyed fabric appearance
• Denier or den (abbreviated D), a unit of measure for the linear mass density of fibers, is the
mass in grams per 9000 meters of the fiber.
mayankbindal.com
Moisture Regain

• Moisture regain is the amount of moisture that a textile fibers or yarn will absorb when exposed to a
specific level of humidity.
• Moisture regain = 100 * W/D
• Where D = Oven Dry weight of fiber , W= Weight of water in fiber
• The moisture regained from textile fibers is affected by the manufacturing process.
• Fibers with high moisture regain will absorb more moisture from the air, making them more
comfortable to wear in humid environments, and more prone to shrinking and wrinkling.
• Fibers with low moisture regain, on the other hand, will absorb less moisture from the air, making them
less shrink or wrinkle, and be less comfortable to wear in humid environments.

mayankbindal.com
Moisture content
• Moisture content is a measurement of the amount of moisture present in a textile fiber.
• The amount of moisture in a material when expressed as a percentage of total weight is known as the
percentage moisture content.
• Moisture content = 100 * W/(D + W) [Where D = Oven Dry weight of fiber , W= Weight of water in fiber]
• Moisture content becomes the factor in the physical properties of the fibers; those are strength,
elasticity, and flexibility.
• Fibers with high moisture content will be weaker, less elastic, and less flexible than fibers with low
moisture content.
• Moisture content reduces the dyeability of the fibers. Fibers with high moisture content are more
difficult to dye than fibers with low moisture content.
• This is because the water in the fibers can interfere with the chemical reactions that take place during
the dyeing process, resulting in uneven or inconsistent coloration.
• Moisture content can reduces the comfort of the textile product. Textiles with high moisture content can
feel clammy and uncomfortable against the skin,
while textiles with low moisture content can feel dry
and scratchy.
• Moisture content eases of processing the fibers into
yarns and fabrics. High moisture content can cause
fibers to stick together, making them difficult to spin or
weave, while low moisture content can cause fibers to
break or become brittle, making them difficult to
process. mayankbindal.com
Cross-Section

• The cross section depicts the shape of the various textile fibers. Each textile fiber offers a distinct cross
sectional appearance when seen under a microscope. The shapes vary from round to oval and flat,
different shapes determines certain characteristics of the textiles.
• The cross-section of a fiber has an effect on the appearance, hand, drape, flexibility, and moisture
wicking properties.
• The cross sectional shape or form of the fibers specifies their texture.
• Numerous physical characteristics such as hand, bulkiness, and luster are associated with cross sectional
shape.
• Synthetic fibers with a more regular surface seem brighter than natural fibers with an irregular
surface, with the exception of silk, which has a regular surface.

mayankbindal.com
Dye selection for particular fibers

 Dyes are fiber specific based on the chemical nature of the dye and the molecular nature of the fiber.
 Chart which shows the most commonly used textile fibers and what classes of dyes work with each
fiber (represents with X).

mayankbindal.com
3.1 Count/Ply & CV%

 Yarn linear density or thickness of yarn

 Weight and length are the key factors in calculating yarn count.
 There are two systems of expressing yarn number or yarn count.
❶ Direct yarn numbering system (mass/unit length)
This means the higher the yarn count number, the heavier or thicker the yarn. It is fixed length system.
❷ Indirect yarn numbering system (length/unit mass)
This means the higher the yarn count number, the finer or thinner the yarn. It is based on the fixed weight
system.
 Count CV% should be within predefined standard.
 Ply refers to the number of strands or fibers the yarn has. Three-ply yarn, for example, is composed of
three single strands that are twisted together.

mayankbindal.com
Yarn hairiness

 It is a desirable property in certain situations and undesirable in other circumstances, depending upon
the type of end-use and application of the resultant fabric.
 The hand and thermal insulation of textiles call for the most hairy yarn.
 On the other hand, high-speed knitting and weaving machines require
a less hairy yarn.
 It also influences the abrasion resistance of fabrics.

Yarn Structure (Diameter & bulk)

• Yarn diameter helps to determine how closely the yarns can be packed to make a fabric or how well
a given yarn will cover in a given fabric. Although yarn count serves the purpose of defining yarn
fineness, sometimes it is essential to calculate the exact diameter of the yarn.
• In certain applications, yarn fineness expressed in diameter or thickness provides more useful
information.
• For example, determining the structural features of a fabric (e.g., cover factor, yarn crimp, etc.)
requires a prior knowledge of yarn diameter.
• Since thousands of ends or wales are presented side-by-side in the woven or the knit fabrics, a slight
change in yarn diameter can result in a substantial change in the overall cover factor of fabric. Factors
affecting yarn diameter are essentially those that affect yarn density or fiber compactness.

mayankbindal.com
 Bulking creates air spaces in the yarns, imparting absorbency and improving ventilation.
 Bulk is frequently introduced by crimping, imparting waviness similar to the natural crimp of wool fibre.

Elongation

 The fabric woven from synthetic fibres has more elongation percentage than natural fibres.
 The fabric woven from coarse and short staple fibre shows poor elongation than fine and long staple
fibre.
 The fabric woven of fine yarn pose more elongation than coarse yarn.

3.2 Significance of blends

 A blend is a mixture of two or more fibers. In yarn spinning, different compositions, lengths, diameters,
or colors may be combined to create a blend.
 Blends help in reducing the discomfort of certain synthetic clothing.
 Synthetic fibers, such as polyester, have a moisture regain rate of only 0.4-0.8 percent. Poor
absorbency reduces the comfort of clothing that comes into direct contact with the skin.
 Blending polyester with absorbent fibers such as cotton ,viscose improves the wearing comfort.

mayankbindal.com
3.3 Twist & twist direction
 Twist is mainly the spiral arrangement of the fibers around the axis of the yarn.
 The twist binds the fibers together and also contributes to the yarn strength.
 The amount of twist inserted in a yarn defines the appearance and the strength of the yarn.
 The number of twists is known as TPI or Twist per inch.
 Twist CV% should be within predefined standard.
 Twist of the yarn depends on :
• Count of yarn to be spun
• Fineness of the fiber being spun
• The softness of the fabric into which is the yarn is to be converted
 There are two types of twist applied in yarn. One is S twist (right twist/clockwise twist) and another
one is Z twist (left twist/anticlockwise twist).
 The twist level has an effect on the properties of yarn as well as fabric. The following parameters are
affected by twist:
• Hand feel, Moisture absorption, Wearing properties, Aesthetic effects, Moisture wicking, Air
permeability, Luster

mayankbindal.com
 .

There are two systems of expressing yarn number or yarn count.

❶ Direct yarn numbering system (mass/unit length)
This means the higher the yarn count number, the heavier or thicker the yarn. It is fixed length system.

 Denier: The weight in grams of 9000 meters of yarn

e.g. 30D indicates that 9000 meters of yarn weight 30 grams.

 Tex: The weight in grams of 1000 meters of yarn

e.g. 30 Tex indicates that 1000 meters of yarn weight 30 grams.

mayankbindal.com
❷ Indirect yarn numbering system (length/unit mass)
This means the higher the yarn count number, the finer or thinner the yarn. It is based on the fixed weight
system.

 English Cotton Count (Ne): Number of 840 yard hanks of yarn per 1 pound weigh
e.g. 30/1 cotton(1 means single yarn) indicates that 30 x 840 yards of yarn weight 1 pound.
e.g. 40/2‟s (2 means ply yarn) indicates that 20(Resultant count)x 840 yards of yarn weight 1 pound.

 Metric Count (Ne): Number of 1000 m (or 1 Km) of yarn per 1 Kg weight
e.g. 30 Nm indicates that 30 kilometers or 30000 meters of yarn weight 1 kilogram.

 Worsted Count: Number of 560 yards hanks of yarn per 1 pound weight
e.g. 1/20 worsted indicates that 20 x 560 yards of yarn weight 1 pound.

mayankbindal.com
Conversion Table

mayankbindal.com
 .

5.1 Woven fabric construction

 Weaving is the process of interlacing sets of yarns together to form a woven fabric structure. .
 Woven fabrics are made of two sets of yarns: warp and filling.
 These yarns are interlaced at 90° to each other .
 The warp yarns are parallel to each other and run lengthwise through the fabric or along the weaving
machine direction.
 In general, there are thousands of warp ends on a typical
weaving machine making a fabric.
 A single warp yarn is called a “warp end” or an “end”.
 Filling yarns run perpendicular to the warp yarns.
 A single yarn of filling is called a “pick”. Other names that
are used for filling yarns are “weft”.

mayankbindal.com
 Symbolic representation of a weave [Fig. A]
 Drawing-in-draft (DID) [Fig. B]
 The reed plan [Fig. C]
 Can draft or Chain draft (CD) [Fig. D]
 Warp and filling profiles [Fig. E]

Fig. A

Fig. B Fig. C
mayankbindal.com Fig. D
 Fig. E

mayankbindal.com
5.2) DIFFERENT TYPE OF WEAVES AND THEIR
APPLICATION

mayankbindal.com
Plain Weave

 Inexpensive to produce, durable, Flat, tight surface is conducive to printing and other finishes.
 Each weft yarn goes alternately over and under one warp yarn. Each warp yarn goes alternately
over and under each weft yarn.
 There is no right or wrong side to plain weave fabric.
 It does not fray as easily as other fabrics.
 It is not as absorbent as other fabrics & crease easily.
 There is no stretch on the length or the width of the fabric only
on the cross grain.
 Plain weave fabrics range in their weight from heavy weight to sheer lightweight fabrics.

Rib weave: The filling yarns are larger in diameter than the warp yarns. A rib weave produces fabrics in
which fewer yarns per square centimeter are visible on the surface.

Matt Weave or Basket weave:

Two or more yarns are used in both the warp
and filling direction. These groups of yarns
are woven as one, producing a basket effect.

Household Uses:
Draperies, tablecloths, upholstery.
mayankbindal.com
Twill Weave
 Diagonal line can be seen on the faced of the fabric.
 Twill line may be from lower lift to upper right (Z-twill) or from lower right to upper lift (S-twill) corner.
 Smaller repeat twill is (3) It means take at least end and three picks produce twill weave.
 Three or more heald shaft are required for shedding.
 Generally straight draft is used for twill weave besides this pointed or v draft is also used.
 Appearance can be seen from both sides the fabric.
 Diagonal lines run at angle vary between (15-75) Degree but in a
continuous or regular twill is 45 degree.
 Better wrinkle recovery
 Twill weaves are more closely woven, heavier and stronger than weaves
of comparable fiber and yarn size.
 High counts possible (more durable)

mayankbindal.com
Satin Weave
 The fabric surface is very smooth and lustrous.
 By using low twisted yarn and by increasing EPI, smoothness can be increased.
 It is usually constructed by floating the warp or lengthwise yarns over four filling or horizontal yarns.
 The long floats give the fabric luster.
 Only one interlacement between warp and weft & interlacement point is covered with adjacent long
float yarn.
 Loose structure compare to plain and twill.
 No visible twill line.
 Widely used in case of jacquard design.
 Smooth, soft luster, Excellent drapability
 Satin is found in apparel, lingerie, draperies, drapery
lining fabrics and upholstery fabrics.

mayankbindal.com
 .

6.1 Introduction of winding process

mayankbindal.com
6.2 Warp preparation
 The warp yarns go through several processing steps before being wound onto a loom beam that will
be inserted at the back of a weaving machine.
 The processes to prepare the warp yarns for efficient weaving comprise what is called warp
preparation; they include warping, slashing, and drawing-in or tying-in.

Direct Warping

 This method of warping transfers yarns from many cones or tubes and winds them simultaneously onto
a section beam in a parallel arrangement called a yarn sheet.
 For spun yarns, a creel typically holds 400 to 800 yarn packages, while filament yarn creels can hold
over 1,000 yarn packages.
 Each section beam contains the same number of yarns. Because most woven fabrics contain well over
2,000 warp yarns, several section beams are needed to provide the required number of warp yarns
for a given fabric construction.
 It is critical that the warp yarns be wound with equal tension, that they not be crossed or rolled over
one another, and that none be lost (broken and not tied back together) or missing.
 Various elements of the warping machine, such as tension devices, static eliminators, broken yarn
detectors, wild yarn (yarn waste) detectors, eyelet boards, and expansion combs help ensure that the
warping machine forms high-quality beams.
 For most fabrics, all section beams must have identical yarn tension, uniform yarn count, and equal
numbers of yarn ends.

mayankbindal.com
Indirect Warping
 This method of warping uses smaller creels with fewer yarn packages and therefore requires less
space.
 Bands or sections of parallel yarns are wound onto a pattern drum.
 The bands are wound parallel to one another, contain the same number of yarns, and are identical in
make-up.
 Indirect warping is preferred for sample work, short runs, and fabrics with pattern stripes.
 The total required number of warp yarns is wound onto the drum, eliminating the use of section beams.
 However, the yarn on the pattern drum must be then be rewound onto a flanged loom beam suitable
for use in further processing.

mayankbindal.com
6.3 Slashing/Sizing
 The purpose of slashing spun yarns is to encapsulate the yarn in a film of size in order to reduce yarn
hairiness, improve yarn abrasion resistance, and increase yarn strength.
 From the creel, the yarns flow through the size box, where the liquid size solution is applied to the
yarn.
 Size concentration, viscosity, and temperature must be constantly controlled.
 Yarn tension and yarn speed on the slasher must also be controlled.
 Squeeze rolls above the size box remove excess size, and the pressure of these rolls helps control size
add-on.
 The yarns are then dried as they move over steam-heated cylinders or cans.
 All of the warp yarns are then laid in parallel fashion through an expansion comb and wound onto a
loom beam.
 The size remains on the warp yarns through the weaving process and then is removed from the fabric
in a preparation process known as desizing.
 Some sizes, such as PVA, can be reclaimed, but starch cannot be reclaimed.

mayankbindal.com
6.4 Drawing-in
 The last warp yarn preparation step is to draw each warp yarn through the appropriate loom
elements, as illustrated in Figure.
 If a given yarn breaks, the associated drop wire makes an electrical contact that stops the weaving
machine.
 The heddles are necessary to control the weave design, and the reed helps to space the yarns equally
and provide a means of pushing, or beating, each weft yarn into the fabric.
 Each opening or space in a reed is called a dent.
 If all yarns are drawn in properly, then weaving will be more efficient, fabric design will be accurate,
and the overall fabric appearance will be acceptable.

6.5 Tying-in
 In mass production of a fabric in the same fabric
design, it is not necessary to redraw the warp yarns
in order to replace a loom beam that has run out
with a new beam of the same style.
 Instead, the much faster process of tying-in can be
used. A tying-in machine takes each end of warp yarn
on the existing loom beam and ties it to the associated
yarn on the replacement loom beam.

mayankbindal.com
 .

7.1 Primary motion

7.1.1 Shedding
 This loom function separates all the warp yarns into a weave shed (opening) formed between a top
shed (yarns that are raised) and a bottom shed (yarns that are not raised).
 Each weft yarn is inserted into the opening created by shedding of the warp yarns.
 Devices called harnesses contain a certain number of heddles through which warp yarns are drawn .
 Harnesses are raised and lowered to produce a particular woven design.

a) Cam shedding
 Cam shedding typically uses 6 to 8 harnesses, though sometimes up to 12.
 Each harness is controlled by a rotating cam that forces the connected harness to move up and down in
a prescribed manner to produce a particular fabric design.
 The profile or shape of each cam and its position on the camshaft dictate the movement of the
connected harness.
 With cam shedding, designs are limited to basic weaves such as plain weave, simple twill weaves, and
common satin weaves

mayankbindal.com
b) Dobby shedding
 Dobby shedding typically uses 12 to 32 harnesses, which allows for a broader range of woven
designs than with cam shedding.
 In addition to the basic weaves, dobby shedding makes it possible to weave small geometric figures,
spot weaves, and more complex pattern stripes.
 Many machines with dobby shedding use plastic sheets with punched holes to direct the harnesses to
be lifted in a certain sequence to produce a given design.
 A punched hole allows a pin to penetrate the sheet and initiate lifting of the associated harness.
 The weave design is thus controlled by the positioning of the holes in the pattern sheet.
 Today, many weavers are investing in electronic dobby shedding machines that work in a much
simplified manner, with no punched sheets.
 Connected with a computer-aided design system, these machines can quickly download and weave a
developed design.

mayankbindal.com
C) Jacquard shedding

 Instead of using harnesses to control the weave design, Jacquard shedding employs draw cords that
drop down from a Jacquard head.

 Each cord is connected to an individual heddle or a small group of heddles.

 This type of control makes it possible to form large design repeats and very intricate designs.

 A given Jacquard machine will have a certain number of hooks that control the lifting of warp yarns.

 Having more hooks makes it possible to weave larger design repeats and more intricate designs.

 Figure shows a Jacquard machine and its associated draw cords.

mayankbindal.com
mayankbindal.com
7.1.2 Picking
 The filling, or weft yarn, can be inserted into the woven fabric by various methods.
 The oldest method, using a shuttle, has been replaced today by various shuttleless methods, which
include rapier, projectile, air jet, and water jet filling insertion.
a) Shuttle weaving
 Shuttles typically are inserted at the rate of 180 to 220 times per minute, referred to as picks per
minute.
 The shuttle contains a quill on which a small amount of filling yarn is wound.
 The yarn unwinds from the quill as the shuttle goes back and forth through the separated warp yarns.
 A fresh quill of yarn is inserted just before the current quill is completely empty.
 Some shuttle machines are still in operation, weaving vintage denim and specialty fabrics.
 Figure shows a shuttle with an empty quill inserted.
 The shuttle is tapered on each end for easy entrance into and exit and out of the weave shed.
b) Shuttleless weaving : Will discuss in next slides

PICKING

mayankbindal.com
7.1.3 Beating
 The reed pushes, or beats, the weft yarn into the woven fabric.
 The reed moves backwards as the filling yarn is inserted in front of it and forward to beat the yarn into the
fabric.
 Reeds are designated by reed number, which indicates the number of dents or slots in the reed per 2 inches
of width.
 For example, a 24 reed number means that the reed contains 24 dents per 2 inch.
 Ends per inch in the fabric divided by ends per dent in the reed equals the reed number.
 The space between dents must be wide enough to allow any slubs
or thick places in the warp yarn to pass through.
 Therefore, each reed has a required amount of air space depending
on whether filament or spun yarn is used; spun yarns require more air space
because of their unevenness.

7.2 Secondary motion

Let-off motion & Take-up

 Let-off, the warp yarn is unwound from the loom beam.

 The rate of let-off must be controlled so that the warp yarns are not under excessive tension during shedding,
which would result in warp yarn breakage.
 Take-up, or removal of fabric from the weaving machine.
 The rate of take-up thus controls the number of picks per inch inserted into the fabric.
 Slower take-up allows insertion of more weft yarns per inch, while faster take-up allows insertion of fewer
weft yarns per inch and results in a higher production rate.

mayankbindal.com
7.3 Tertiary motion or Stop motions
Similar to winding, warp yarns are threaded through tension devices, stop motions, leasing rods and the
reed. Uniform tension is necessary so that all the warp ends behave the same way. The tension on the
warp yarns is kept relatively low. Every end requires a tension controller which is usually located close to
the package

 A quick response, advanced stop motion is necessary for warping. Due to the high inertia of the beam,
it is difficult to stop the beam suddenly once an end is broken.
 However, the beam must be stopped before the broken end reaches the beam.
 The stop motion electrically links each warp end to the warper braking system; when a warp end
breaks, the warper stops.
 Powerful brakes are used for this purpose. A light indicates the location of the broken end.
 The warping process is generally irreversible, unwinding of the beam would cause yarn entanglement.
The stop motion device, which can be mechanical or electronic for quick response, is usually located
near the creel.
 The weft stop motion controls the correct insertion of the weft into the
shed, that is whether the weft has broken or been too short to reach the
opposite end of the shed (short weft).
 This is necessary to prevent missing weft threads called cracks,
in the fabric.

mayankbindal.com
7.4 Fabric control

a) Fabric width
 At the moment it is woven, the fabric width is equal to the reed width as shown in Figure.
 However, as the weaving continues and fabric gets away from the reed, the fabric starts narrowing
due to several factors like(it should be noted that there are certain fabrics which do not get narrower,
e.g. glass fabrics) Crimp, Fabric construction, High weaving tensions, especially in the warp yarns.
 Warp yarns closest to the selvages of the fabric undergo more stress due to widthwise contraction of
the fabric toward the center, causing linear angular displacement of these outermost yarns.
 The narrowing of fabric width should be prevented, by using a temple on each side of the machine.
 A temple is a metallic device that keeps the fabric stretched by applying a force along the filling
direction

mayankbindal.com
b) Selvedge
 Selvedges provide strength to fabric for safe handling of the fabric.
 Selvage should not curl.
 In shuttle looms, there is no need for special selvage; since the yarn is not cut after each filling
insertion, the edges of the fabric are smooth and strong.
 In shuttleless weaving, since the pick yarn is cut after every insertion, there is fringe selvage on both
sides of the fabric.

mayankbindal.com
 .

8.1 Rapier Filling Insertion

 Rapiers are rigid bars or flexible tapes with an attached gripper system to grip the yarn and insert it
across the warp shed.
 Most rapier weaving machines use a left-hand and a right-hand rapier.
 As illustrated in Figure 16, one rapier (the giver) inserts the weft yarn halfway across the weave shed,
where it meets the other rapier (the taker), which enters the weave shed from the opposite direction,
and the weft yarn is transferred from the giver to the taker.
 Each rapier then retracts from the weave shed to complete the process.
 The insertion process is typically repeated 350 to 600 times per minute,
depending on machine width and model.

The sequence of operations on a

double Rapier machine
mayankbindal.com
8.2 Air Jet Filling Insertion
 Air jet weaving machines use a burst of compressed air from an air nozzle to initially propel the filling
yarn across the weave shed.
 Because the air disperses very quickly, additional relay air nozzles are evenly spaced across the width
of the weave shed (as shown in Figure) to allow for weaving of wider fabrics.
 Air jet machines use a special profile reed to create a tunnel configuration through which the air and
filling yarn travel across the weave shed.
 Air jet weaving machines can insert relatively coarse yarns, such as yarns for heavy bottom-weight
denim; however, yarns any heavier than that would be difficult and more costly to weave, because of
the high air pressures required.
 These machines can also weave finer spun yarns, but not ultra-fine yarns that might be blown apart.
 Spun yarns and textured filament weft yarns run well on these machines, but not slick flat filament
yarns, because of their low surface friction.
 Air jet machines have lower maintenance requirements and fewer replacement parts than do rapier
and projectile machines.
 Insertion rates ranging from 600 to 1200
per minute are typical for air jet machines.

mayankbindal.com
Projectile Filling Insertion

 Projectile weaving machines contain a gripper that holds the filling yarn as the projectile is shot across
the weave shed.

 A torsion bar stores up energy as it is twisted; when the energy is released, a connected lever strikes
the projectile, propelling the yarn across the machine.

 A given machine will contain several projectiles, typically one per 10 inches of machine width.

 Projectiles are returned to the picking side of the machine via a type of conveyor-belt system; at any
one time, several projectiles will be on the belt.

 Projectile filling insertion machines typically run at 300 to 550 insertions per minute.

 With fewer moving parts, they require less maintenance than rapier machines.

 Double-width projectile machines can make two separate fabrics with the same set of projectiles, thus
doubling the speed of weaving.

 Projectile machines can produce denim-weight fabrics, as well as shirting weight.

mayankbindal.com
Water Jet Filling Insertion

 In water jet weaving, only hydrophobic fibers and yarns can be used, such as polyester, nylon, and
olefin fibers.

 Most of the fabrics woven on these machines are made of filament yarns, which are less absorbent
than spun yarns.

 A vacuum slot on the front of the machine front helps to remove any residual water from the fabric.

 All machine parts must be made of non-corrosive materials.

 Insertion rate 800 to 1200 picks per minute.

 The fabric most commonly made on water jet machines is mattress ticking.

mayankbindal.com
 .

mayankbindal.com
 Safety aspect
i. Safety doors
ii. Emergency switches
iii. Fire detection system
iv. Precautions during cleaning
v. Safety Check list
vi. Use of PPE kit while dealing with chemicals

mayankbindal.com
Technical Aspects of Warping

 No. of warping machines, their makes, model, manufacturing year, and approx cost.
 Technical specifications of warping machine (creel type, creel capacity, type of tensioners, stop
motions, cutter, etc.)
 About creel design (peg to peg distance, peg rod to peg rod distance, balloon breaker, tensioner rod
etc).
 About the head stock zone (eg. parts and their functions).
 Specifications of warpers beam (flange diameter, barrel diameter etc.)
 Count wise standard machine speed and settings.
 SOP during cone finish (cones used after cone finish, storage of cones for further use etc.)
 Waste generated in warping department (waste %, waste handling etc.)
 Housekeeping
 Calculation of beam density, efficiency, utilization, end breakage rate, and their comparison with a
standard.
 Measurement of warping tension, beam hardness, etc. (eg. Instrument used, the procedure followed,
and comparison with standards). TECHNICAL ASPECT
 RH and temperature of warping department and its impact on quality.
 Various types of faults and their identification (eg. spinning fault, winding fault, etc)

mayankbindal.com
Technical Aspects of Drawing-in

 Types of reeds, drop pins, and heald wires and their specifications.(eg. reed space ,reed
denting order, dimensions, eye dimensions, duplex ,simplex etc.)
 Quality wise, sort wise reeds, drop pin, heald wires selection
 Reed count checking during drawing.
 Check the quality of heald wire, drop pin and reed.

TECHNICAL ASPECT

mayankbindal.com
Technical Aspects of Weaving-Loom Shed

 Different types of looms with their makes and model.

 Technology-wise total number of looms and there basic differences (eg. loom width, type of shedding,
picking mechanism, beat-up, speeds, specifications, drives, no. of motors etc.)
 Functions of pre-winder and its different diameters for different fabric width.
 Functions of weft breaking systems during picking
 Knowledge about the various settings required during sort change activity (eg. Pre-winder setting, air
pressure setting, etc.)
 Different types of stop motions and there remedies (eg. warp stop, weft filling, package sensors, etc.)
 Knowledge about the different types of warp and weft breaks at different position (eg. H1, H2, false
stop, multiple breaks etc.)
 Indication lamp of machine and there means for different color code.
 Different types of temples used on loom (eg. Medium, superfine, 3-row, plastic etc.)
 Specification of temples with respect to various qualities of fabrics.
 How to do mechanical zero setting, basic setting in warp part and weft part of
various technology. TECHNICAL ASPECT

mayankbindal.com