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Greige Fabric Inspection

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Page 1: Session 1 & 2 - Greige Fabric Inspection

Greige Fabric Inspection

Page 2: Session 1 & 2 - Greige Fabric Inspection

Greige Fabric

Newly constructed fabric as it comes from the mill is called as greige fabric

The goods must pass through various processes to make it suitable for its intended use

Page 3: Session 1 & 2 - Greige Fabric Inspection

GREY ROOM GREY ROOM OPERATIONSOPERATIONS

Fabric inspection involves following three Fabric inspection involves following three

processesprocesses

• PerchingPerching

• BurlingBurling

• MendingMending

Page 4: Session 1 & 2 - Greige Fabric Inspection

GREY ROOM GREY ROOM OPERATIONSOPERATIONS

Perching It is a visual inspection and it is carried out

through the inspection table which consists of a frosted glass

with lights behind and above it.

The fabric imperfections like thick places, defects, yarn knots, stains and other flaws are marked.

Burling It is the removal of yarn knots or other imperfection

from the fabric.

Page 5: Session 1 & 2 - Greige Fabric Inspection

GREY ROOM OPERATIONSGREY ROOM OPERATIONS

Mending is the actual repair of imperfections.

• The recent innovation by the use of laser beams. • The imperfections like stains, holes, thick places, loose ends

and protruding threads of warp and weft are detected.

• Eliminates human error.

Sewing: After the goods have been inspected, checked and classed

in the grey room, according to quality and stamped, they are

sewn together, end to end, by sewing machines

Page 6: Session 1 & 2 - Greige Fabric Inspection

• Fabric Inspection

Principle Importance Types of Inspection Requirements Inspection Systems

• Fabric Defects

Minor, Major and Serious Woven & Knitted

Page 7: Session 1 & 2 - Greige Fabric Inspection

Defects

visualsTextile Committee\presentation.exe

Page 8: Session 1 & 2 - Greige Fabric Inspection

Major Defect:

A defect that, if conspicuous (clearly visible) on the finished product, would cause the item to be a second.

A "second" is a garment with a conspicuous defect that affects the sale-ability or service-ability of the item.

Minor Defect:

A defect that would not cause the product to be termed a second either because of severity or location.

Page 9: Session 1 & 2 - Greige Fabric Inspection

WOVEN FABRIC DEFECTS

Jerk-in (major/minor) - Caused by an extra piece of filling yarn being jerked part way into the fabric by the shuttle. The defect will appear at the selvedge

Knots (minor) - Caused by tying of yarns together.

Burl Mark (major) - extra piece of yarn is woven into the fabric

Drawbacks (major) - Caused by excessive loom tension applied by some abnormal restriction. When the restriction is removed the excess slack is woven into the fabric. Usually the ends are broken

Dropped Pick (major) - Caused by the filling insertion mechanism on a shuttle-less loom not holding the filling yarn, causing the filling yarn to bewoven without tension.

Page 10: Session 1 & 2 - Greige Fabric Inspection

End Out (major) - Caused by yarn breaking and loom continuing to run with missing end

Mixed End (major) - Yarn of a different fiber blend used on the warp frame, resulting in a streak in the fabric

Mixed Filling (major) - Caused by bobbin of lightweight yarn or different fiber blend used in filling. Will appear as a distinct shade/color change

Open Reed (major) - Results from a bent reed wire causing warp ends to be held apart, exposing the filling yarn.

Slub (major/minor) - Usually caused by an extra piece of yarn that is woven into fabric. It can also be caused by thick places in the yarn. Often caused by fly waste being spun in yarn in the spinning process

Page 11: Session 1 & 2 - Greige Fabric Inspection

Smash (major) - Caused by a number of ruptured warp ends that have been repaired

Soiled Filling or End (major) - Dirty, oil looking spots on the warp or filling yarns, or on package-dyed yarn

Stop Mark (major/minor) - When the loom is stopped, the yarn elongates under tension; when loom starts again the slackness is woven into the fabric

Thin Place (major) - Often caused by the filling yarn breaking and the loom continuing to run until the operator notices the problem

Page 12: Session 1 & 2 - Greige Fabric Inspection

Barre (major) - Caused by mixing yarn on feed into machine. Fabric will appear to have horizontal streaks

Birdseye (major/minor) - Caused by unintentional tucking from malfunctioning needle. Usually two small distorted stitches, side by side

Broken Color Pattern (major) - Usually caused by colored yarn on frame.

Drop Stitches (major) - Results from malfunctioning needle or jack. Will appear as holes or missing stitches.

End Out (major) - Results from knitting machine continuing to run with missing end

KNITTED FABRIC DEFECTS

Page 13: Session 1 & 2 - Greige Fabric Inspection

Hole (major) - Caused by broken needle

Missing Yarn (major) - Caused by one end of yarn missing from feed and machine continuing to run

Mixed Yarn (major) - Results from wrong yarn (or wrong size yarn) placed on feed. Fabric could appear as thick end or different color if fibers have different affinity for dye

Needle Line (major/minor) - Caused by bent needle forming distorted stitches. Usually vertical line

Page 14: Session 1 & 2 - Greige Fabric Inspection

Press-Off (major) - Results when all or some of the needles on circular knitting fail to function and fabric either falls off the machine or design is completely disrupted or destroyed.

Runner (major) - Caused by broken needle. Will appear as vertical line.

Most machines have a stopping device to stop machine when a needle breaks

Slub (major/minor) - Usually caused by a thick or heavy place in yarn, or by lint getting onto yarn feeds.

Page 15: Session 1 & 2 - Greige Fabric Inspection

•Inspection

Page 16: Session 1 & 2 - Greige Fabric Inspection

PRINCIPLEInspection

Detection of defects

Feedback of these defects to appropriate personnel

Determination of causes of defects

Correction of the defects

Page 17: Session 1 & 2 - Greige Fabric Inspection

IMPORTANCE

• Fabric inspection is done to determine its acceptability.

• If inspection is not done, it may result in

(a)Loss of the material

(b)Loss of time

(c)Dissatisfaction due to poor quality

(d)Poor customer return

Page 18: Session 1 & 2 - Greige Fabric Inspection

Inspection Inspection is carried out mainly to appraise the quality of

products in terms of manufacturing defects and adherence to the specifications and other requirements.

Normally, the visual inspection is carried out on the fabric to examine the occurrence of yarn defects, fabric defects, design/colors besides specification particulars

In the earlier days, the inspection was mainly carried out to segregate the defective products from the good products thereby controlling the quality of products at the exit points.

Page 19: Session 1 & 2 - Greige Fabric Inspection

In the late 80s, the concept of quality has undergone total transformation from quality control to quality assurance and total quality management.

In the changed scenario, the inspection is mainly carried out to ascertain that the products conform to requirement and initiate suitable corrective and preventive action if otherwise.

Page 20: Session 1 & 2 - Greige Fabric Inspection

Types of Inspection There are two ways of doing inspection viz. 100% inspection

and sampling inspection.

The 100% inspection is generally carried out to segregate the products quality-wise and perform mending activity for products having mendable defects whereas the sampling inspection mainly focus on sentencing the lot or batch for acceptance or otherwise based on the sample.

This will lead to reduction in defects in the final product, rejection level, replacement and thereby improve the quality of the final product which results in quality image in the market

Page 21: Session 1 & 2 - Greige Fabric Inspection

Requirements of Inspection Inspection and Mending is to be carried out on a flat table

in a well illuminated/ ventilated place.

Inspection equipments like counting glass, a good calibrated tape, metallic comb, clipper-plucker needle are to be provided to the checkers

Page 22: Session 1 & 2 - Greige Fabric Inspection

CHECKING OF DIMENSIONSMEASUREMENT OF WIDTH:Width shall be measured at three different places of the fabric and recorded.

While measuring width, care should be taken

o · to remove the wrinkles/ crease gently from the fabric surface.o· to keep the measuring tape straight across the fabric horizontally from selvedge to selvedge.o· to measure the width as far as possible near the centre avoiding the ends.o· not to stretch the fabric while measuring.

Page 23: Session 1 & 2 - Greige Fabric Inspection

MEASUREMENT OF LENGTH:Fabric to be measured for length and actual length recorded.

Length is measured by any of the following methods

o· By passing through metre counter fitted roller.o· By manually clipping the fabrics in the fold measuring frame.o· By counting the number of metre fold in case of folded fabrics.

oCare to be taken to ensure that the folds are of one metre length by measuring a few folds.

Page 24: Session 1 & 2 - Greige Fabric Inspection

CHECKING OF CONSTRUCTIONALPARTICULARS

ENDS PER INCH:Ends per inch shall be counted at two places along the width of the fabric and recorded.

PICKS PER INCH:Picks per inch shall be counted at three places along the length of the fabric and recorded.

Care to be taken while placing the pick glass to see that the edges of the template should coincide with the yarn. Ends/Picks per inch may be counted for one inch. Also the picks should not be counted at defective places like weft bars and cracks.

Page 25: Session 1 & 2 - Greige Fabric Inspection

WEIGHT PER SQ.MTR.:Pieces are to be weighed and recorded. Weight per square metre to be calculated and recorded.

CALCULATION OF WEIGHT/SQ.MTR.:· Weigh the individual piece under Inspection and note-down.· Work out the sq.mtrs. of the piece by multiplying the length of the piece in mtrs. and width of the piece in mtrs.Calculate wt./sq.mtrs . as:

Weight in kgs.---------------------------------------------------

Length in mtrs. X Width in mtrs.

Page 26: Session 1 & 2 - Greige Fabric Inspection

Inspection Systems There are three different systems for grading the quality of

fabric, which are as follows:

SYSTEM . I (FLAW BASED) In this system, depending upon the magnitude, defects are

classified as minor, major or serious.

Note:

1) Minor Flaws:

Minor flaws occurring more than one in number within 15 cms. length of the cloth shall be reckoned as one minor flaw only

Page 27: Session 1 & 2 - Greige Fabric Inspection

2) Major Flaws:

a)Major flaws occurring more than one in number within a length of 15 cms. of the cloth shall be reckoned as one major flaw only.

b)Major flaws occurring in a consecutive length beyond 15 cms. shall be reckoned as one major flaw each for every 15 cms. or part thereof.

Page 28: Session 1 & 2 - Greige Fabric Inspection

3) Selvedge Defects:

a)In case of furnishing fabrics all selvedge defects like pulled in selvedge, wavy selvedge etc. of minor nature are also to be reckoned as major flaws.

b)Defective or damaged selvedge exceeding 5% of the length of the piece in case of furnishing fabrics are to be reckoned as serious flaw.

c)All types of selvedge defects or weaving defects very close to the selvedges are not to be reckoned in case of fabrics used for making garments/made-ups.

Page 29: Session 1 & 2 - Greige Fabric Inspection

ACCEPTABILITY CRITERIA FOR FLAWS: The acceptability level for “first” quality fabric is usually

established by mutual agreement between the buyer and the seller.

The different types of fabrics have different point levels of acceptability depending upon their end use.

Some of the commonly followed standard for acceptability for the above mentioned systems are listed here

Note: Minor flaws : @ 25 per 100 meters maximum are

acceptable. Serious flaws: No serious flaw is acceptable.

Page 30: Session 1 & 2 - Greige Fabric Inspection

Sample size (m)

Acceptd no. of major flaws

Sample size (m)

Acceptd no. of major flaws

Standard.A-1 Standard A Standard.A-1 Standard A

1200 29 40 350 7 10

1175 28 39 325 6 9

1150 27 38 300 6 8

1125 26 37 275 5 7

1100 26 36 250 4 6

1075 25 35 225 4 6

1050 25 34 200 3 5

1025 24 33 175 3 4

1000 23 32 150 2 3

975 23 31 125 2 3

950 22 31 100 1 2

Page 31: Session 1 & 2 - Greige Fabric Inspection

SYSTEM . II (4-POINT SYSTEM)

The 4-point system, also called the American Apparel Manufacturers Association (AAMA) point grading system for determining fabric quality, is widely used by producers of apparel fabrics and by the Department of Defence in the United States

Fabric flaws or defects are assigned point values based on the following:

Page 32: Session 1 & 2 - Greige Fabric Inspection

Length of defect in fabric, either length or width

Points allotted

Up to 3 in. (7.5 cms.) 1

Over 3 in. (7.5 cms.) up to 6 in (15 cms.) 2

Over 6 in. (15 cms.) up to 9 in. (23 cms.) 3

Over 9 in. (23 cms.) 4

Holes and openings(largest dimension)

Points allotted

1 in. (2.5 cms.) or less 2

Over 1 in. (2.5 cms.)4

Page 33: Session 1 & 2 - Greige Fabric Inspection

The maximum number of defect points to be counted against any one linear yard/metre is four points.

Overall, fabric quality is assessed on the basis of the number of defect points per 100 sq yards/sq mtrs. of fabric.

ACCEPTABILITY CRITERIA FOR FLAWS:

Normally fabric rolls containing up to 40 points per 100 sq yds. and 48 points per 100 sq mtrs. are acceptable.

However, based on the price line and end product more or less than 40/48 points per 100 sq. yds./100 sq mtrs. respectively may be accepted.

Page 34: Session 1 & 2 - Greige Fabric Inspection

Example - 1 A fabric roll of 120 yds. long and 48 in. wide contains the

following defects:

2 defects up to 3 in.

5 defects over 3 in. but less than 6 in.

1 defects over 6 in. but less than 9 in.

1 defect over 9 in.

Page 35: Session 1 & 2 - Greige Fabric Inspection

Points/100 sq. yds

Total points scored in the roll

= ---------------------------------------------------

Fabric width x Total yard inspected

Answer??????????????????????????????????????

Page 36: Session 1 & 2 - Greige Fabric Inspection

2 defects up to 3 in. 2 x 1 = 2 points5 defects over 3 in. but less than 6 in. 5 x 2 = 10 points1 defects over 6 in. but less than 9 in. 1 x 3 = 3 points1 defect over 9 in. 1 x 4 = 4 points

TOTAL =19 points

Page 37: Session 1 & 2 - Greige Fabric Inspection

Therefore, Points/100 sq. yds.

Total points scored in the roll x 3600

= ---------------------------------------------------

Fabric width in inches x Total yard inspected

19 x 3600

= ---------------

48 x 120

= 11.9 defect points/100 sq. yds.

So if the acceptance criteria is 40 points/100 sq. yds. then this roll is acceptable.

Page 38: Session 1 & 2 - Greige Fabric Inspection

Example - 2:A fabric roll of 100 m long and 150 cm wide contains the following defects:

3 defects up to 7.5 cm. 6 defects over 7.5 cm. but less than 15 cm.2 defects over 15 cm but less than 23 cm.1 defect over 23 cm.

Answer?????????????????????????????

Page 39: Session 1 & 2 - Greige Fabric Inspection

SYSTEM . III (10-POINT SYSTEM)

No linear yard of fabric is assigned more than 10 points, no matter how bad or frequent the defects are.

Acceptability criteria for flaws:

Fabric is considered of “first” quality if the number of defect points are less than the number of yards of fabric inspected.

In the case of fabrics wider than 50 in., the fabric is considered of first quality if the total defect points do not exceed the number of yards of fabric inspected by 10%.

Page 40: Session 1 & 2 - Greige Fabric Inspection

Length of defect, Warp defects

Points allotted

Up to1 inch 1

1 to 5 inch 3

5 to 10 inch 5

10 to 36 inch 10

Filling defect (weft defect) Points allotted

Up to 1 inch 1

1 to 5 inch 3

5 inch to half-width 5

Larger than half-width 10