fabric faults & remedy-updated

MD. SAIDUL HAQ MASUM Production Officer (Weaving)

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ARTICLE ON:

FAULTS IN WOVEN FABRIC & THEIR REMEDY

Prepared By:

MD. SAIDUL HAQ MASUM B.Sc. In Textile Engineering (CU)

MBA In Textiles (BUTex) [Ongoing] Production Officer (Weaving)

Ha-Meem Denim Ltd. Mawna, Sreepur, Gazipur.

e-mail: [email protected]

P

reface:

This article has prepared based on my practical findings about faults in woven (denim) fabrics. Here I have focused on the frequently occurring weaving faults in woven (denim) fabrics. I hope this article will be helpful for any kind of research & development related with woven fabric faults & heir recovery. t

I am specially thanking to the authority of Ha-Meem Denim Ltd. MD. SAIDUL HAQ MASUM Friday, June 14, 2013


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FAULTS IN WOVEN FABRI & THEIR REMEDY

The international textile market is quite quality sensitive. Therefore to have a sound knowledge about the quality of textile products is essential for the person oriented with the textile manufacturing & marketing. Here I am going to focus on the faults of woven fabric & their recovery procedure. The frequently occurring faults in weaving can be categorized as follows: a) Faults related with Warp. b) Faults related with Weft. c) Faults related with loom operation. d) Faults due to poor vigilance. e) Miscellaneous faults. The frequently occurring faults in weaving are enlisted bellow according to their category: a) Faults Related With Warp:

In this category the following faults exist:

1. Double Ends. 2. End Out/Miss Warp. 3. Wrong Drawing-In. 4. Wrong Denting. 5. Balls.

b) aults Related With Weft:F

In this category the following faults exist: 6. Snarls. 7. Broken Pick. 8. Miss Pick. 9. Weft Yarn Fault.


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c) aults Related With Loom Operation:F In this category the following faults exist:

10. Starting Mark. 11. Temple Mark. 12. Line Mark. 13. Crease Mark.

d) Faults Due To Poor Vigilance:

In this category the following faults exist: 14. Weft Yarn Count Mistake. 15. Weft Yarn Ratio Mistake. 16. Unwanted Slub In Weft. 17. Slub Miss In Weft.

e) Miscellaneous Faults:

In this category the following faults exist: 18. Gout.

The causes of formation of these faults & their recovery procedures are described bellow in detail.

a) Faults Related With Warp: 1. Double Ends: When two adjacent warp ends are drawn through the same heald eye, then those two ends are woven in the same weave & faulty fabric is produced. This fault is known as double ends. Causes: ■ The most vital cause of double ends is incorrect drawing. Always each warp ends should be drawn through each heald eye. But if two adjacent warp ends are drawn through the same heald eye, then it will result the formation of double ends.


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■ Double ends can also be resulted due to the negligence during warping or sizing. When any end is being broken during warping or sizing; then it should be mended (re-knotted) with the respective end. But sometimes the operators of warping or sizing don’t do that. Rather they wrap that broken end with an adjacent end to save their time. As a result, when that end reaches to the heald eye, it enters into the heald eye with the other end with which it wrapped. As a result double end is being woven. Remedy: ■ Drawing-in should be done very carefully. ■ If any end is being broken during warping or sizing, it should be mended re-knotted) with the correct respective end. (

■ The operators should have to be trained & careful. As they can find any

ouble ends& can mend it right there. d ■ Vigilance in the weaving floor should be increased in such a level that no double ends can run for a long time. That means, when a double ends just passes the weaving zone, it should be find out & mend right there. 2. End Out/Miss Warp: When any warp end is missed in the woven fabric, then it is called end out or missed warp. Causes: ■ The main cause of end out is the malfunction of warp stop motion. Now a days all kinds of automatic & semi-automatic looms are provided with warp stop motion. Vital working elements of warp stop motion are electrode & drop-wires. The purpose of warp stop motion is to stop the loom immediately just then, when any warp yarn is broken. Each warp end is being drawn through the drop-wires. The drop-wires remain under tension by the warp ends & therefore they can’t touch the electrode. As any warp end breaks, the corresponding drop-wire falls on the electrode & shorts the two metal parts of the electrode; that sends a signal to the processor of the loom & stops the loom immediately. Now if the drop-wire fails to touch the electrode when a warp end is being broken, then the loom will continue to run with the broken end. This will


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cause to woven the fabric with a missing end; that means the fault- end out will be resulted. The described phenomenon happens when the drop-wires & electrode are being blocked by dust or any kind of other non-conductive substances. ■ End out can also be caused due to drawing-in any warp end through the heald eye without drawing that yarn through drop-wire. Remedy: ■ Loom should be kept neat & clean; so that the warp stop motion doesn’t malfunction. The operators should be ordered strictly to clean the drop wires &electrode properly after a regular periodic interval by directing compressed ir. a

■ During drawing-in it should be confirmed that each warp end has drawn hrough drop-wires. t

■ Vigilance in the weaving floor should be increased in such a level that when an end out just occurs, it could be find out & mend right there. 3. Wrong Drawing-In: The fault in a woven fabric that is caused due to the incorrect order of drawing-in is called wrong drawing-in. Drawing-in is done according to the Drafting Plan. Drafting plan is a graphical instruction that indicates which warp end will be drawn through heald wire of which heald shaft. The described tropics will be clear with some practical illustrations. So let us have a look to the following designs on page-6 & 7. There are 3 designs. The drafting plan of design-A (3/1 Right Hand Twill) & design-B (3/2 Vertical Herringbone) are Straight Draft, where the no. of heald shafts is equal to the no. of ends in the repeat. The drafting plan of design-C (3/3Dimond) is “V” Draft, where the no. of heald shafts is half of the no. of ends in the repeat.


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↑SHA 4 → → → → → → → Shafts 1 2 3 4F 3 → → → → → → ↓T 2 → → → → → ↓ ↓ E * 1 2 3 4S 1 → → → → ↓ ↓ ↓ N

↓ ↓ ↓ ↓ D * 5 6 7 8↑ 4 4 SP 3 3 → Up (Warp Yarn) * 9 10 11 12I 2 2 ToC 1 1 → Down (Weft Yarn) Be * 13 14 15 16

Ks # 1 2 3 4 1 2 3 4D * 17 18 19 20RAW * 21 22 23 24N

10 → → → → → → → → → → → → → →9 → → → → → → → → → → → → → ↓8 → → → → → → → → → → → → ↓ ↓

↑ 7 → → → → → → → → → → → ↓ ↓ ↓S 6 → → → → → → → → → → ↓ ↓ ↓ ↓H 5 → → → → → → → → → ↓ ↓ ↓ ↓ ↓A 4 → → → → → → → → ↓ ↓ ↓ ↓ ↓ ↓F 3 → → → → → → → ↓ ↓ ↓ ↓ ↓ ↓ ↓T 2 → → → → → → ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓S 1 → → → → → ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓

↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓ ↓↑ 5 ↑ 5P 4 P 4 → Up (Warp Yarn)I 3 I 3C 2 C 2 → Down (Weft Yarn)K 1 K 1S # 1 2 3 4 5 6 7 8 9 10 S 1 2 3 4 5 6 7 8 9 10

Note: Drawing In Instruction of Design-B Is Same as Design-A

Drawing-In Instruction

And So On

Weave PlanShafts→

Lifting PlanEnds→

Created By M@SUM

Drafting Plan

Design-A: 3/1 Right Hand Twill

(Based On 3/2 Right hand Twill)Design-B: 3/2 Vertical Herringbone

Ends→Weave Plan

Shafts→Lifting Plan

Drafting Plan

↑ 6 → → → → → → → → → →S 5 → → → → → → → → → ↓H 4 → → → → → → → → ↓ ↓A 3 → → → → → → → ↓ ↓ ↓F 2 → → → → → → ↓ ↓ ↓ ↓Ts 1 → → → → → ↓ ↓ ↓ ↓ ↓

↓ ↓ ↓ ↓ ↓ ↓12 1211 1110 109 98 87 76 6 → Up (Warp Yarn)

↑ 5 ↑ 5P 4 P 4 → Down (Weft Yarn)I 3 I 3C 2 C 2K 1 K 1S # 1 2 3 4 5 6 7 8 9 10 11 12 S 1 2 3 4 5 6

Shafts 1 2 3 4 5 612 → 1 2 5 6

E * 1 2 3 4 5 6 11 → 1 4 5 6N 11 10 9 8 7 12 10 → 3 4 5 6D 9 → 2 3 4 5S * 13 14 15 16 17 18 8 → 1 2 3 4

23 22 21 20 19 24 7 → 1 2 3 6To 6 → 1 2 3 4Be * 25 26 27 28 29 30 5 → 2 3 4 5

35 34 33 32 31 36 4 → 3 4 5 6D 3 → 1 4 5 6R * 37 38 39 40 41 42 2 → 1 2 5 6AW 47 46 45 44 43 48 1 → 1 2 3 6N

Created By M@SUM

And So On

Drawing-In Instruction

Shaft To Be LiftedPicks

Design-C: 3/3 Dimond

Drafting Plan

Ends→ Shafts→Weave Plan Lifting Plan

The drawing-in instruction of these designs are also shown. MD. SAIDUL HAQ MASUM

Production Officer (Weaving) Ha-Meem Denim Ltd.

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The fault- wrong drawing-in occurs when the warp ends are drawn in wrong order. For example let us illustrate design-A.

Here the repeat consists of 4 ends; that should have to be drawn in four separate heald shaft serial wise.


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Now if 19 no. warp; that should have to be drawn through the heald eye of 3 no. heald shaft is drawn through the heald eye of 1 or 2 or 4 no. heald shaft; then it should result in wrong drawing. As a result of wrong drawing the corresponding end/ends are being woven in wrong order & therefore faulty fabric is produced.

Shafts→ 1 2 3 4

* 1 2 3 4 * 5 6 7 8 * 9 10 11 12 * 13 14 15 16 * 17 18 19 20 * 21 22 23 24 * 25 26 27 28 * 29 30 31 32

Ends To Be D

rawn↑

And So On

Causes: ■ Incorrect order of drawing. Remedy: ■

Drawing-in should be done very carefully.

■ Vigilance during mounting a new beam should be strict enough so that wrong drawing-in can be detected & rectified immediate after running a new beam & it doesn’t occurs any more after mending once. 4. Wrong Denting:


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The fault in a woven fabric that is caused due to the incorrect order of enting of warp ends through the reed is called wrong denting. d

For example; let us consider a fabric is running with 71 EPI in a loom having reed count 698 DM (DM→ Dents Per Miter). So 4 ends should be drawn through each dent of the reed. Now if more or less then 4 ends are

rawn in any one of the dent; then it will result in wrong denting. d Due to wrong denting line mark is produced in the fabric. Causes: ■

Incorrect order of denting of warp ends through the reed during denting.

■ Incorrect order of denting of warp ends through the reed after breakage of warp end. Remedy: ■ Denting should be done very carefully. ■ Vigilance during mounting a new beam should be strict enough; so that wrong denting can be detected & rectified immediate after running a new beam. ■ After warp breakage if it needs to draw the broken end through the dent of the reed; then this task should be done very carefully & the fabric should be checked properly immediate after re-starting the loom for detecting the existence of wrong denting. 5. Balls: When small globular fibrous substances appear on the fabric surface (either on face or on back or on bath side); then it is called balls. Balls are the result of entanglement of fibrous substances on the yarn surface. Usually all kinds of yarns contain more or less hairiness. When those protruding fibers are being aborated by the loom parts like drop-wires, heald eyes & dents; the yarn become more hairy. When some hairy warp ends passes together through a single dent; the protruding loose fiber on their surface tends to be entangled together. In this way balls are generated. Existence of fibrous dust in the weaving floor emphasizes the formation of balls.


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Causes: ■

Excessive hairiness in the warp.

■ Drawing more no. of ends then recommended through the dents of the eed. r

■ Rough surface of drop-wires, heald eyes & dents of the reed. ■ Excessive fibrous dust in the weaving floor. ■ Less cleaning effort of looms. Remedy: ■

Better quality warp (less hairy) should be used.

■

Excessive no. of ends shouldn’t be drawn through the dents of the reed.

■ Rough surfaced drop-wires, heald eyes & dents of the reed (if any) should be changed. ■ Standard temperature & RH% should be maintained for reducing floating dust. ■ The weavers beam (mounted on the loom) & the yarn sheet exposed from the weavers beam to the weaving zone should be cleaned after a regular interval by directing compressed air.

b) Faults Related With Weft: 6. Snarls: Snarl is the result of defective pick insertion. When a weft yarn can’t pass through the shed smoothly & obstacles in its path then snarl is formed. Due to snarl formation the fabric surface take a rough look & rough hand fill at the place where snarl has formed. Causes: ■ Defective picking arrangement.


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■

Incorrect setting of picking arrangement.

■

Incorrect air pressure in air-jet looms.

■ Polyester or any other synthetic yarn show higher tendency of snarl ormation. f

■ When cotton-lycra plied yarn is used as weft yarn in air-jet looms, then after each loom stoppage if the weft yarn end doesn’t release from nozzle during re-starting loom; then there is too much higher possibility of snarl formation. Remedy: ■

Faultless picking arrangement should be used.

■

Accurate setting of picking arrangement should be confirmed.

■ In air-jet looms air pressure should be adjusted accurately depending on the yarn type (cotton/synthetic, single ply/multiple ply, lycra etc.). ■ During using polyester or any other synthetic yarn, extra vigilance should be imposed. ■ When cotton-lycra plied yarn is used as weft yarn in air-jet looms, after each loom stoppage the weft yarn end must be released from nozzle during re-starting loom. 7. Broken Pick: If any weft yarn doesn’t reach to the other side of the selvedge; rather it remains at any place between two selvedges of both sides then this fault is termed as broken pick. Due to broken pick a mark is found across the width of the fabric that is visualized in that place where the weft yarn is missing. Causes: ■ In case of air jet looms this problem is created due to excess air pressure or fluctuating air pressure. Excessive air pressure cause the weft yarn to be torn & thus broken pick is inserted. ■ In any kind of loom broken pick can be generated due to defective pick nsertion arrangement. i

■ Incorrect setting of pick insertion arrangement is another vital cause of roken pick b

■

Insufficient strength of weft yarn is responsible for broken pick.

■ Malfunctioning of the weft stop motion is another vital cause of broken pick. All modern looms are provided with electric weft stop motion. This motion is provided with a sensor that is fitted to the opposite side from the picking side. This sensor bears 3 LED at its sensing head. The setting is done in such way that each weft yarn passes through beneath of those LED. When the sensor finds that a pick has already been inserted but it has not reaches to the Led; then the sensor will send a signal to the processor of the loom that will stop the machine immediately.


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According to the described mechanism it seems that there is no possibility of insertion of broken pick until the sensor works on properly.

Figure-1

The Sensing Head Courtesy : Ha-Meem Denim Ltd.

But sometimes the LED in the sensing head becomes covered with dust; as a result the sensor fails to detect broken picks. If the sensor bears any electrical or mechanical fault; that will also fail to detect broken picks, but in this case any corresponding signal lamp or the display of the loom will provide message about the fault of sensor. Remedy: ■ In case of air jet loom pressure setting should be adjusted accurately. ■ Pick insertion arrangement should be checked regularly & defective pick insertion arrangement (if any) should be replaced. ■

Accurate setting of pick insertion arrangement should be confirmed.

■

Bad weft packages should be avoided.

■

Functioning & setting of weft stop sensor should be checked regularly.

■ The sensing head of the weft stop sensor should be cleaned by soft cloth for several times within a shift for preventing it’s malfunctioning for dust.


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■ Atmospheric cleanliness should be ensured for preventing malfunctioning of pick insertion arrangements & weft stop sensors. Standard atmospheric condition (temperature & RH %) should be maintained in the weaving floor. 8. Miss Pick: When a pick doesn’t insert but the loom continues to run with a pick missing; then faulty fabric is being produced. This fault is termed as miss pick. Due to miss pick; a horizontal mark is visualized across the full width of the fabric. The mark is obtained in that place where the pick had missed. Causes: ■

Defective pick insertion arrangement.

■

Incorrect setting of pick insertion arrangement.

■ Malfunctioning of the weft stop motion due to dust or electrical or mechanical problem. Remedy: ■ Pick insertion arrangement should be checked regularly & defective pick nsertion arrangement (if any) should be replaced. i

■

Accurate setting of pick insertion arrangement should be confirmed.

■

Functioning & setting of weft stop sensor should be checked regularly.

■ The sensing head of the weft stop sensor should be cleaned by soft cloth for several times within a shift for preventing it’s malfunctioning for dust. ■ Atmospheric cleanliness should be ensured for preventing malfunctioning of pick insertion arrangements & weft stop sensors. Standard atmospheric condition (temperature & RH %) should be maintained in the weaving floor. 9. Weft Yarn Fault: In fact weft yarn fault is not a weaving fault. This fault is obtained due to bad quality of weft yarn. Darker & lighter shaded bands obtained across the


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full width of the fabric either in periodic (most common) or non periodic order. The shaded bands are prominent on that side on which the weft yarn is prominent. For example, in case of 3/1 right hand twill fabric the shaded bands will be prominent on technical back side of the fabric. But in case of 1/1 plain fabric the shaded bands will be prominent on both sides of the fabric. Causes: ■ Bad weft supply package. Remedy: ■

Bad weft supply package should be avoided.

■ Vigilance should be strict enough; so that weft yarn fault can be detected rectified immediately when it starts to occur. &

■ During & after feeding new weft supply package; fabric should be checked properly for detecting weft yarn fault (if any).

c) Faults Related With Loom Operation: 10. Starting Mark: Starting mark is a fabric fault that is created due to loom stoppage. When a running loom stops for any reason; then after re-starting the loom a horizontal mark across the fabric width is visualized. This is called starting mark. Basic reason of formation of starting mark: When a loom continues to run then both the warp ends & the weft yarn remain in motion. Sudden stoppage of loom will break that motion & due to he inertia the fell of the cloth will not reach at the correct position. t

Starting mark is created when fell of the cloth doesn’t remain at the correct position; rather it stays slightly rearer position. As the fell of the cloth stay rearer then its accurate position; so the newly inserted weft doesn’t mash with the cloth fell properly, rather a slight gap exist between the cloth fell & the newly inserted pick. As a result starting mark is created.


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Basic mechanism for preventing formation of starting mark: Modern looms are provided with automatic anti starting mark procedure. The purpose of this procedure is to prevent the formation of starting mark. The basic mechanism for preventing starting mark is different for different

rands of looms. Here I am giving the description of two procedures. b ■ In PICANOL looms after each loom stoppage the take-up roller along with the fabric moves in opposite direction. So, the fell of the cloth moves slightly backward (towards the reed). Therefore after re-starting the loom, the reed will strike the newly inserted pick at a comparatively high force then that of the regular force. As a result the gap between the cloth-fell & the

ewly inserted pick (if any) should be removed. n ■ In TSUDAKAMA looms the mechanism of automatic anti starting mark procedure is based on reed motion. In this loom after each loom stoppage when the loom is re-started the reed strike is done at a higher force then regular beat-up. This higher beat-up force will remove the gap between the cloth-fell & the newly inserted pick (if any). Causes: ■

Incorrect setting of reed in its profile.

■

Incorrect setting of back-rest.

■ Incorrect tension on the warp. ■ After loom stoppage for weft stop, it is recommended to remove one pick before re-starting the loom. But if more then one pick is removed; then starting mark can be obtained. ■ Excessive jerking in the weaving zone during stoppage & starting a loom due to mechanical problem. ■ In case of looms provided with automatic anti starting mark procedure excessive delay for re-starting a loom after stoppage will result in formation of starting mark. Remedy: ■ Setting of reed should be accurate.


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■ Setting of back-rest should be accurate depending on warp yarn count & eave. w

■ Tension on the warp should be accurately set depending on the warp yarn ount. c

■ Any kind of undue jerking should be avoided by proper setting & regular servicing of loom. ■ In case of loom stoppage due to weft stop only one pick should be removed. ■ In case of looms provided with automatic anti starting mark procedure; the loom should be re-started as early as possible after each stoppage. 11. Temple Mark: Temple mark is one of the most typical faults in woven fabric. It comes vertically in the fabric beneath within the range of the temple width. In case of fabrics produced from dyed warp, a white mark is visualized across the length of fabric due to temple mark. In case of fabrics produced from grey warp, the problem associated with temple mark is being visualized after dyeing. In this case shade variation occurs across the area affected by temple mark. Causes: ■ Defective temple, e.g. blunt temple ring, jammed temple ring or roller. ■

Incorrect setting of temple support.

■ Incorrect setting of temple. Remedy: ■ If temple is defected; that should be changed. ■ The setting of temple support should be correct. ■ The setting of temple should be correct.


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■ Some times temple mark comes even after taking all the described actions. In that case; the temple should be dis-assembled & some of the temple ring should be removed from it. The temple rings should be removed until that portion where the temple mark had generated. Then the temple should be re-assembled again. 12. Line Mark: Line mark is a fabric fault for which vertical mark appears in fabric. It may appears in one place or more than one places at a time. Causes: ■ Improper arrangement of warp ends with different counts is one of the most vital reasons of line mark. Sometimes there may be more than one count in a single beam. For example let us consider the following construction: (7Oe+9 Oe+12 Oe) x 16-L40D/66 x 46 Oe→ Open End. [1:2:2] 16L-40D→ 16 Lycra-40 Denier.

Here the warp contains 3 types of yarns having different counts. Those are 7Oe, 9 Oe & 12 Oe. Their corresponding ratio is 1:2:2. That means throughout the warp sheet there should be 1 end of7Oe , 2 ends of 9 Oe & 2 ends of 12 Oe. This arrangement of warp must be maintained throughout the warp sheet. Where this arrangement will be broken; there line mark will be obtained. ■ Defective loom parts e.g.-drop-wires, heald eyes & dents of the reed. ■ Wrong denting. ■ Existence of foreign count in the weavers beam. For example, let a weavers beam contains warp of 30R (Ne). Now if one single end of 40R (Ne) or 16R (Ne) or any other count except 30R (Ne) exist in that beam; then the fabric produced from that beam will bear a line mark in the place where the yarn of foreign count [40R (Ne) or 16R (Ne) or any other count except 30R

(Ne)] exists. Remedy:


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■ In case of beams that contains warp ends with different counts; the ends should be properly arranged by maintaining the correct ratio. Proper rrangement of warps can be achieved by leasing. a

■

Defective loom parts should be replaced (if any).

■

Wrong denting should be avoided.

■ Foreign count should be avoided. Foreign count in the beam is the result of defective warping. So warping should be done carefully. But if foreign count exist in the beam; then it should be detected & replaced by the reserve end of accurate count. 13. Crease Mark: Most of the modern looms are provided with batchers; on which the produced fabric is being rolled. It is expected that a fabric roll should be cylindrical in shape. But sometimes rolls are found to be slightly funnel shaped (convex on one side of the roll & concave on other side of the roll). Due to this unwanted shape, fabric tends to be curled on the concave edge. When any portion of fabric is being curled that portion is being warped with other layers of fabric. So eventually the curled portion has to withstand huge pressure as the roll becomes larger in size. As a result crease mark is generated on the curled portion of the fabric. Causes: ■ Incorrect shape of roll on the batcher when it is formed. ■ Improper synchronization between batcher speed & take-up roller speed. ■ Loose or imbalanced tension on both edge & centre on the fabric that exists between batcher & take-up roller. Remedy: ■

Shape of roll on the batcher should be accurate cylindrical.

■ Batcher speed & take-up roller speed should be properly synchronized. ■ Tension on the fabric that exists between batcher & take-up roller should be sufficiently balanced on both edge & centre. The fabric roll should be formed under sufficient high tension.

d) Faults Due To Poor Vigilance:

14. Weft Yarn Count Mistake: Sometimes wrong count of weft yarn is feed in the loom; that results weft yarn count mistake. For example let a particular style requires 16/1 Ne as weft yarn. Now if 12/1 Ne or 16/1 Oe yarn or any other yarn except 16/1 Ne is used for that fabric; then the produced fabric will be faulty. Causes: ■ Poor vigilance. ■ Careless duty of the operators & line in-charges. Remedy: ■ Strict vigilance should be confirmed so that this fault can be detected & ectified immediately when it occurs. r

■ Operators & line in-charges should be more careful. 15. Weft Yarn Ratio Mistake: Some fabrics require 2 or more different types of yarn. The weft yarns may contain different ratio. Two constructions of such fabrics are given bellow:

Ratio Distribution Sl. No. Construction Weft Yarn Ratio

12Oe 1 1. 30R x (12Oe+16Oe)/66 x 45 (1:1) 16Oe 1

16Oe 1 2. 20R x (16Oe+300DPL)/71 x 52 (1:3) 300DPL 3

R → Ring Yarn Oe → Open end DPL→ Denier Polyester

During manufacturing fabrics containing different weft yarns with different ratios; it should be confirmed that accurate ratio have set for each particular ype of yarn. t


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For clear impression let us illustrate the 2nd construction. Here there are 2 different weft yarns. 16Oe should insert 1 pick & 300DPL should insert 3 picks. If we select 1 pick for both type of yarn or the reverse ratio(16Oe →3

icks 300p

DPL →1 pick) then faulty fabric will produced.

In case of modern looms which are provided with display; the weft ratio can set & checked very easily by using the display. In case of semi-automatic looms; the ratio is set manually. Causes: ■ Poor vigilance. ■ Careless duty of the operators & line in-charges. Remedy: ■ Strict vigilance should be confirmed so that this fault can be detected & rectified immediately when it occurs. ■ Operators & line in-charges should be more careful. 16. Unwanted Slub In Weft: If any fabric doesn’t require slub yarn as weft yarn; but slub yarn is inserted as weft yarn, then the fault is termed as unwanted slub in weft. Causes: ■

Faulty weft package that contains unwanted slub.

■

Poor vigilance.

■

Careless duty of the operators & line in-charges.

Remedy: ■ Faulty weft package should be avoided. ■ Strict vigilance should be confirmed so that this fault can be detected & rectified immediately when it occurs. ■ Operators & line in-charges should be more careful. 17. Slub Miss In Weft: If any fabric requires slub yarn as weft yarn; but yarn without slub is inserted as weft yarn, then the fault is termed as slub miss in weft.


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Causes: ■ Poor vigilance. ■ Careless duty of the operators & line in-charges. Remedy: ■ Strict vigilance should be confirmed so that this fault can be detected & rectified immediately when it occurs. ■ Operators & line in-charges should be more careful.

e) Miscellaneous Faults: 18. Gout: Gout is not a frequently occurring fabric fault it occurs seldom. If any small hard but pliable material e.g.- small pitch of wood or hard paper or polythine is being woven in the fabric, then when that material is taken out from fabric; a hole appears in that place where the foreign material existed. This fault is known as gout. Causes: ■

Falling of any small hard but pliable material in the weaving zone.

■ Floating dust in the weaving floor. Remedy: ■ Floor cleanliness should be strengthen. ■ Standard temperature & RH% should be maintained for reducing floating dust. These are the faults that frequently occur in weaving.

…………… ■ ……………

fabric faults & remedy-updated

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