Spirality and shrinkage are common problems in knitted fabrics that can be influenced by various factors. [1] Spirality occurs when wales are not perpendicular to courses and is affected by yarn twist, count, fabric structure, and machine settings. [2] Shrinkage is a decrease in length or width upon washing and is mainly due to yarn swelling; it can be impacted by GSM, stitch length, and fabric type. [3] The document discusses measuring and reducing spirality and shrinkage through parameters like yarn and fabric properties as well as processing methods.
(Over Dyeing) to dye for a second or third time with a different color. Over dyeing is such a rewarding way of rescuing an ugly or unsatisfactory colored cloth. It gives uneven look. sometimes over dyeing doesn’t mean all-time dyeing the garment which is previously dyed. Over dyeing may be normal dyeing or piece dyeing process.
Denim is a sturdy cotton warp-faced textile in which the weft passes under two or more warp threads. This twill weaving produces a diagonal ribbing that distinguishes it from cotton duck.
Denim is available in a range of colors, but the most common denim is indigo denim in which the warp thread is dyed while the weft thread is left white. As a result of the warp-faced twill weaving, one side of the textile is dominated by the blue warp threads and the other side is dominated by the white weft threads. Jeans fabricated from this cloth are thus predominantly white on the inside.
Bahauddin Zakariya University College of Textile Engineering.
Warp knitting is a family of knitting methods in which the yarn zigzags along the length of the fabric, i.e., following adjacent columns ("wales") of knitting, rather than a single row ("course"). For comparison, knitting across the width of the fabric is called weft knitting.Warp knitting machines--needles are mounted collectively and rigidly in a horizontal metal bar (the needle bar that runs the full knitting width of the machine).
(Over Dyeing) to dye for a second or third time with a different color. Over dyeing is such a rewarding way of rescuing an ugly or unsatisfactory colored cloth. It gives uneven look. sometimes over dyeing doesn’t mean all-time dyeing the garment which is previously dyed. Over dyeing may be normal dyeing or piece dyeing process.
Denim is a sturdy cotton warp-faced textile in which the weft passes under two or more warp threads. This twill weaving produces a diagonal ribbing that distinguishes it from cotton duck.
Denim is available in a range of colors, but the most common denim is indigo denim in which the warp thread is dyed while the weft thread is left white. As a result of the warp-faced twill weaving, one side of the textile is dominated by the blue warp threads and the other side is dominated by the white weft threads. Jeans fabricated from this cloth are thus predominantly white on the inside.
Bahauddin Zakariya University College of Textile Engineering.
Warp knitting is a family of knitting methods in which the yarn zigzags along the length of the fabric, i.e., following adjacent columns ("wales") of knitting, rather than a single row ("course"). For comparison, knitting across the width of the fabric is called weft knitting.Warp knitting machines--needles are mounted collectively and rigidly in a horizontal metal bar (the needle bar that runs the full knitting width of the machine).
Terry fabric is a knitted fabric with ring yarn or terry covering at one or both sides. It belongs to one of the fancy knitted fabrics. Terry fabric is characterized by soft touch, thick texture, excellent water absorption and heat retention. Terry fabric can be divided into single-sided and double-sided terry loop fabrics. The terry can form pattern effect on the knitting surface distributed according to some certain rules. Terry fabric after shearing or other process can be turned into fleece fabric or velvet fabric.
Pile fabrics: Manufacturing methods include woven pile fabric formation & others methods such as knit pile fabric, tufted pile fabrics etc. A "Terry" or a "Terry Towel" as is generally known is a woven pile fabric formed by slack tension weave process. of weaving.
This presentation is my graduation internship presentation at BSL (LNJ group) Bhilwara (Rajasthan).
In this presentation I describe BSL company profile, Process significance, all steps which use for fibre to fabric in textile.
Terry fabric is a knitted fabric with ring yarn or terry covering at one or both sides. It belongs to one of the fancy knitted fabrics. Terry fabric is characterized by soft touch, thick texture, excellent water absorption and heat retention. Terry fabric can be divided into single-sided and double-sided terry loop fabrics. The terry can form pattern effect on the knitting surface distributed according to some certain rules. Terry fabric after shearing or other process can be turned into fleece fabric or velvet fabric.
Pile fabrics: Manufacturing methods include woven pile fabric formation & others methods such as knit pile fabric, tufted pile fabrics etc. A "Terry" or a "Terry Towel" as is generally known is a woven pile fabric formed by slack tension weave process. of weaving.
This presentation is my graduation internship presentation at BSL (LNJ group) Bhilwara (Rajasthan).
In this presentation I describe BSL company profile, Process significance, all steps which use for fibre to fabric in textile.
For meeting the demand of 21th Century we need many qualified Textile Engineer but in our perspective there are two types of Textile Engineer one is more qualified another is more frantic about their position. No Frustration because you are the right key to touch your success. Don’t draw your life map with pen but pencil (because pencil is erasable). Let bygones be bygones & go ahead with our future as if it will be keep in touch. Make a whistle with vivacious life & vivid future.
Knitting 2 sum For Fabric Very ImportantSadia Textile
Types of warp knitting m/c:
Two major classes of warp knitting m/cs:-
1. Tricot warp knitting m/c
2. Raschel warp knitting m/c.
Features Tricot warp knitting m/c:
In the past, tricot m/cs mainly employed bearded needles with a pressure bar
Tricot m/cs have a gauge expressed in needle per inch and chain link numbering 0, 1, 2, 3, 4 etc. generally with three links per course
Their sinkers, which are joined to each other at the front and back, never move clear of the needles as they combine the functions of holding down, knocking over and supporting the fabric
The fabric is drawn-away towards the batching roller almost at right angles to the needles bar
A terry towel is a textile product which is made with loop pile on one or both sides generally covering the entire surface or forming strips, checks or other patterns. Special type of weaving technique is required for terry towel manufacturing. Terry towels are often very complex with yarns of different types and colors, in combination with various loop pile and flat structures. The name "terry" comes from the word "tirer" which means to pull out, referring to the pulled out by hand to make absorbent traditional. Turkish toweling Latin "vellus" meaning hair has the derivation "velour" which is the toweling with cut loops.There are many types of towel. Baby Towel, Bath Towel, Beach Towels, Golf Towels ,Hand Towel and Hotel Towels now used commonly.
2. SUPERVISING TEACHER
A.K.M FARIDUL AZAD
Assistant Professor
Head Of The Department
Department of Fabric Manufacturing Technology
Pabna Textile Engineering College,
Shalgaria, Pabna-6600
Name Exam Roll Reg. No. Session
MD.EKRAMUL HASAN 070065 4534 2006-2007
PREPARED BY
3. Abstract
• Spirality is a common problem in weft knitted fabric. It is the de-
twisting tendency of yarn in the fabric. It appears in mostly in
single jersey fabrics but in double jersey fabrics this level in
about zero. The causes of formation of spirality in twistness in
the yarn and increase it by using more number of needles and
multifeeders machine so on. It can reduce in different ways but
not remove from the fabrics.
• Shrinkage is the dimensional change in length and width wise in
the fabric. It mainly occurs for swelling of yarn. So, it appears
more in cotton fabrics than synthetic fabrics. It can reduce the
shrinkage by using stenter machine after dyeing and drying the
fabric. Also, if the higher GSM/lower stitches length/lower twist
fabric contains lower shrinkage of fabric.
• For measuring the spirality and shrinkage at first we have done
ISO-6330 washing then use ISO: 16322-2 for spirality and ISO-
5077 for shrinkage. And these are international standard of
these measuring systems.
4. Shrinkage: A dimensional change resulting in a decrease in the length or width
of specimen subjected to specified condition is known shrinkage.
Spirality: If the Wales of the knitted fabric are not perpendicular to the course
and skew to the right or left Spirality occurs in the fabric. This creates serious
problem, especially in the apparel industry.
Yarn twist: Twist is the measures of the spiral turns given to a yarn in order to
hold the constituent fibers or threads together. Amount twist i. e. TPI greatly
influenced the fabric Spirality.
Twist liveliness: The tendency of a yarn is to twist or untwist spontaneously.
The direction of twist liveliness or torque S or Z twist change that takes place
spontaneously when an end or hanging loop is allowed to rotate freely. Higher
amount of twist leads high liveliness and creates fabric Spirality.
Dry Relaxed State: The fabric moves to this state with time. The dry relaxed is
restricted by fabric structure and fiber type. Only wool can attain this state.
Wet Relaxed State: Static soak in water and dry flat. This state tight structure
doesn’t always reach a true relaxed state. Only wool and silk can attain this
state. Soak water with agitation or agitation in steam or static soak at selected
temperature (below 900
C)
5. Calculation for spirality percentage:
X =Average
deflection length from
the seam line
Y= Sample length,
Spirality% =
Washing process:
ISO 6330
Determination of spirality after laundering knitted fabrics:
ISO 16322-2
7. Considering the following parameters can
control spirality
Count
The yarn is finer, the spirality will be more due to more twisting.
Fig: Effect of spirality on GSM (34Ne
Combed yarn)
Fig: Effect of spirality on GSM (26Ne
Carded yarn)
8. Twist
Twist multiplier:
TM=TPI/√count
So when TM is increased, TPI also increased & the spirality of fabric also increased.
TM Twist liveness (cm) Spirality (degree)
3.2 19.69 4.2
3.5 25.99 6.5
3.8 28.96 7.3
Twist factor:
TF= TPcm × √tex
So, when TF is increased, TPcm also increased & spirality of fabric also increased.
9. Blending of fibre
• 100% cotton yarn shows more spirality than polyester-
cotton blend yarn on different procedure of dry.
FOR 100% COTTON OF SINGLE JERSEY
FOR BLENDED (COTTON + POLYESTER) OF SINGLE JERSEY
10. Fabric structure
• In single jersey fabric has more spirality than rib & interlock.
• No appreciable problem of spirality in rib & interlock fabric.
Effect of fabric structure with Tumble dry on spirality
11. GSM
• In plain single jersey fabric GSM increases, spirality
decreases.
12. Direction of m/c rotation
• Z-twist yarn gives z skew, s-twist gives s-skew
to the fabric. With multifeed m/cs , the fabric
is created in helix, which gives rise to course
inclination & consequently wale spirality .
Direction depends on the rotational direction
of the knitting m/c. Earlier research work
revealed that, for a clockwise rotating m/c,
the wale would be inclined towards the left.
Thus producing the spirality.
13. Effect of stenter m/c
Before stenter (For Plain Single Jersey Fabric):
After stenter (For Plain Single Jersey Fabric):
If the fabric is delivered to the dryer without sending through the
stenter m/c and completed garments that show lower spirality,
higher shrinkage. On the contrary, it shows tolerate
limit according to buyer requirements by going through the stenter m/c.
14. Types:
• Relaxation shrinkage,
• Felting shrinkage,
• Compressive shrinkage,
• Residual shrinkage.
Causes:
• Shrinkage is mainly due to yarn swelling and the
resulting crimp increase during washing in case of
cotton fabrics. Yarn swelling percentage is more
in polyester cotton blending yarn.
15. Influencing factors:
• Twist factor: twist factor increases so that shrinkage will be
increases.
• Stitch length: stitch length increases so that shrinkage will be
increases.
• GSM: GSM increases so that shrinkage will be decreases.
• Elasticity of yarn.
Calculation for shrinkage percentage:
• Shrinkage percentage = (L0-L1) ×100/L0
• Where, L0 = the distance between the datum line before washing
and
• L1 = the distance between datum lines after washing.
Washing process:
• ISO 6330
Determination of dimensional change in washing and drying:
International Standard ISO 5077
16. Effect of GSM on Shrinkage (Tumble Dry)
•
In plain single jersey fabric lengthwise and
widthwise decreases with increase in GSM.
Fig: Effect of GSM on Shrinkage in lengthwise
(Tumble Dry)
Fig: Effect of GSM on Shrinkage in widthwise (Tumble
Dry)
17. • In plain single jersey fabric has higher
shrinkage than rib and interlock.
Effect of Fabric Structure on Shrinkage(Tumble Dry)
Fig: Effect of GSM on Shrinkage of different
types of fabrics in length wise (Tumble Dry)
Fig: Effect of GSM on Shrinkage of different
types of fabrics in widthwise (Tumble Dry)
18. • In Terry Fleece Fabric spirality and shrinkage are increases then Fleece
Fabric.
EFFECT OF SINGLE JERSEY DERIVATIVES ON SPIRALITY & SHRINKAGE
(FLEECE & TERRY FLEECE)
19. Result and discussion
• From our project work we can conclude that, in case of
higher count, combed yarn, lower GSM, 100% cotton yarn
used, single jersey structure cause the higher spirality in
the weft knitted fabrics. Also, if anti-clockwise machine
direction and Z twisted yarn causes lower spirality. By using
plating yarn we get lower spirality. Form our experiment
we can also see that among the three drying processes the
result of tumble dry shows greater spirality and flat dry is
lower.
• In case of shrinkage higher the GSM, higher the stitch
length it cause higher shrinkage. In case of fleece, two
thread fleece contains more shrinkage than three thread
fleece. Also we observe from our experiment, the polyester
fabric contains lower shrinkage than 100% cotton fabric.
• Though our project is vast, but we don’t get among time to
arrange the experiment data exactly. It needs more time
data to describe these topics.
20. Remedies For Spirality
Z & S twist yarn package used in alternate feeder:
If Z and S twist yarn packages are used in alternate feeder
then legs than 1% spirality is found and this is the greatest
way to reduce spirality;.
Resin treatment:
Cross linking the fabric by means of inter fibre bonding also
reduces spirality. Resin is the form of aqueous solution is
applied and set by passing the fabric through a high
temperature stenter this method is not recommend fro
cotton fabrics, since it weakens the cotton yarn.
Heat setting:
Steam or hot water setting reduces twist liveliness and
hence spirality. Mercerization is recommended for cotton
yarn, sot that fibers are made to relax permanently.
21. Remedies For Spirality
Compacting:
If the length of the fabric based on its elongation during processing which,
in turn, reduces the width. It helps in controlling the shrinkage of the
fabric. There are two types of compactors, open and tubular. In tubular
compacting the squeezing line gets on the sides in this process and is
done on natural movement thus controlling spirality. If the wales are
straightened manually then it results in spirality.
Yarn twist direction and machine rotation direction:
If the machine rotates clockwise then the spirality can be reduced by
suing yarn of S-twist. Otherwise if the machine rotates anti-clockwise the
spirality can be reduced by using the yarn of Z-twist.
Use of special type of yarn:
One comparative way minimize the spirality is to use the vortex spun yarn
which is obtained from Murata vortex spinning system. And modified
friction spun DREF III yarn reduces yarn snarling and fabric spirality.
By using plating yarn:
In fabric production when used plating yarn it reduce the spirality.
22. Remedies for Shrinkage
• In order to maintain the weight at a lower shrinkage, a
finer yarn is used.
• In order to maintain the width, a larger diameter
knitting machine or a longer stitch length is necessary.
• In order to maintain the same knitted tightness factor,
or cover factor (square root of tex divided by stitch
length) with a finer yarn, a shorter average stitch
length must be knitted.
• Changes in yarn count and stitch length also change
the stitch density which again changes the weight and
the width for a given level of shrinkage. Changes in the
tightness factor will change the extensibility of the
fabric and will also affect the amount of spirality
(fabric twisting) which may be developed.