Fabric Inspections

D.S.C. JayasingheB.Sc. Eng ( Moratuwa )

1. 100% Shade Grouping2. Color Confirmation3. 10% Fabric Inspection4. GSM Testing5. Shrinkages - Testing

Inspections & Testing'sDone at Fabric Inspections

1. Swatches of fabric is cut away from each roll at

the unloading stage.2. Each Piece is given the roll number of it’s origin.3. Cut away pieces from these swatches are shade

grouped under the standard lighting conditions of the relative Buyer.

4. If the fabric is for washed garments , then the shade grouping is done after washing.

5. Grouped Shades are inserted in to the computer software for the information of cutting department.

100% Shade Grouping

Swatches of fabric is cut away from each roll at the unloading stage.

100% Shade Grouping

Roll number is written down on the piece

100% Shade Grouping

These pieces are shade grouped under the standard lighting conditions of the certain Buyer. For washed garments, this is done after washing the piece.

100% Shade Grouping

1. Solid Color Fabrics should be folded along the

width of the fabric.2. Stripes Should be folded across the stripes

when shade grouping.3. Small prints should be grouped based on the

size of the print as well.4. Stripes should be grouped considering the

repeat width also.5. While achieving all the above, work towards

achieving the minimum shades possible.

Shade Grouping Tips

Shade Grouping Tips

A roll with a Different

Repeat Width Should be put

in to a Different Shade

Shade Grouping Tips

A roll with a Different Size Prints Should be put in to a

different Shade

Shade Groups are Finally Entered in to a System for the information of cutting

100% Shade Grouping

The color of The bulk is checked Against an approved bulk Hanger.

** Matching of rolls in aBulk Shade should be very higher Than the matching of bulk Hanger With the bulk shades.

Color Confirmation

1. 3 Pieces of Fabric is cut away diagonally from

each roll of 10% inspection.2. 3 Circles ( each = 1/100 of a square meter) is cut

away using the circular cutter from these pieces and measure the weight.

3. The weight of all 3 pieces is totaled and divided by 3 to get the median value.

4. A piece closer to the median value is affixed in the GSM report and mention the GSM.

GSM Testing

3 Pieces of Fabric is cut away diagonally from each roll of 10% inspection.

GSM Testing

3 Pieces ( 1/100 of a square meter) is segregated using the circular cutter from

these pieces and measure the weight

GSM Testing

Measuring the weight of a pieces.

GSM Testing

Calibrated Scale is used to measure the weight

of the piece.

3 Pieces together or individually measured by this method. Divide the total value by 3 to get the median value.

When we multiply this value by 100, we

receive the actual GSM of the fabric.

GSM Report is Prepared affixing one pieceCloser to median value ofThe GSM of the fabric,

+/- 5% tolerance Is acceptable.

GSM Report

1. 10% of rolls are taken from every batch at the

unloading stage.2. Rolls are inspected according to standard 4

point inspection method.3. Based on the average point count

0-16 Points – Fabric Pass 16-28 Points – Fabric in the High Fault Rate

Range 28 + -- Fabric is Rejecting

10% Fabric Inspection

Rolls being inspected

We use standard 4 point inspection method for grading and

inspecting fabric. Based on this method the points to defects are given as follows. Maximum points can be given to a linear

yard is 4.

Inspection Method

Defect Size / Type Points Given

Hole 4

Other Defects

0”-3” 1

3”-6” 2

6”-9” 3

9” + 4

There are several types of fabric defects. Few of them can be

mentioned as follows.1. Fly Yarns2. Holes3. Slubs4. Stains5. Printing Mistakes6. Miss Yarns ( Composites )7. Missing Wales8. Dye Patches9. Crease Marks10. Thick Yarns11. Thin Yarns12. Dirt Marks

Defects on Knitted Fabrics

This is due to Different color yarn contaminate with the fabric. Points are given based on the

size , 90% of fly yarns can be removed by using sharp tweezers , Fly Yarns can be easily removed on a 100% cotton fabric than in a 95/5 Cotton /

Spandex Mix. Higher the yarn thickness easier the removing of

fly yarns.

Fly Yarn

Fly Yarn ( Image )

Holes are due to various issues , Mostly due to breaking of knitting needles. Damages due to sharp instruments is also a reason for holes , Holes are always given 4 points neglecting it’s size, Holes are hard to repair and consume more technical skills and sharp instruments.

Hole

Hole ( Image )

Slubs are due to entangling of yarns and slubs precent in the raw yarns. Points to a slub is given based on it’s size. Repairing of slub need excellent patience and skill.

If a slub is not repaired correctly it would end up as a hole.

Slubs

Slub ( Image )

Stains ( Image)

Stains occur due to chemicals and natural material as well. There are basically 3 types of stains.

1. Water Born Stain2. Oil Born Stain3. Heat Set Stain

Approximately 99% of all stains are removable on white fabrics while it is quite hard to remove on a color fabric due to the objective of saving the color.

Stains

Stains have 2 basic combination which affect the fabric

1. Bonding with the fabric2. Color

For oil born stain you have to use a hydrocarbon ( Thinner ) to remove the stain from bonding , For a water born stain you can use water or an alcohol ( Surgical Spirit ). To remove the color of a stain you have to use a tough oxidizer ( Liquid Chlorine ). When you are testing trial an error method for a stain you have to begin with water , hot water and soap before all others.

Stains ( How to Remove )

Printing mistakes happen due to various reasons.

1. Damage of the Screen2. Screen Setting off3. Squeegee malfunctioning4. Tension of the fabric is wrong or varying

Most of the Printing mistakes become critical and impossible to repair, some small damages are

correctable yet you may need buyers approval for uncured painting.

Printing Mistake

Printing Mistakes ( Image )

Usually a miss yarn in a knitted fabric should be

an opening of the fabric , Yet in a composite fabric( ex. 95/5 Cotton / Spandex ) a miss yarn can be found with the availability of the body

yarn or the elastic yarn.

Miss Yarns

Miss Yarn ( Image )

Dye patches occur due to pouring of chemicals

carelessly, due to having less homogeneous dye baths and entanglements of the fabric in the dyeing process. Points are given based on the

size of the defect.Dye patches are hard to be corrected.

Dye Patches

Dye Patches ( Image )

A continuous gap between adjacent wales is called as a missing wale. Missing wales are due to continuing of knitting at the breakage of a needle or malfunctioning of a needle lifting

mechanism.

Missing Wale

Missing Wale ( Images )

Crease Marks Happen due to the crushing of fabric at the finishing stage , rolling stage and transport stage and stocking stage as well.

Crease marks on knitted fabrics is not a serious defect while it become very serious on woven fabrics.

Crease Marks

Crease Marks ( Image)

Thick yarns occur due to feeding of higher thickness of yarn to the knitting machine or lower tension of a certain yarn.

Thick yarns cannot be correct at a sewing facility.

Thick Yarns

Thick Yarn ( Image )

Thin yarns occur due to feeding of lower thickness yarn to the knitting machine or higher tension of a certain yarn.

Thin yarns cannot be correct at a sewing facility.

Thin Yarn

Thin Yarn ( Image)

Long looped courses are specially can be seen at 95 / 5 Elastane blends. This happens due to the breakage of elastic yarn at the knitting stage,

when the elastic yarn is broken the loop length of a certain course increases and the fabric

become more transparent along that course.

Long Looped Courses

The long loops seen with the

assistance of a backlight

Long Loops ( Images )

Dirt marks occur mainly at rolling stages, packing and transporting stages ,

Most dirt marks are easily washable yet should and can be avoided.

Dirt Marks

Inspection report is prepared by inserting length, width, points, correctly.

The point count is expressed as Average Points Per 100 Square Yards.

Next slide will describe the complete method of calculating Average point count.

Preparing Inspection Report

Formula to Calculate Average Point Count

4 Point Inspection Report

Points 0 to 16 - Fabric Pass

Proceed Normally

Points 16 to 28 – Fabric is in High Fault Rate range

Need to do CPI prior issuing to line

Points 28 + - Fabric is in Rejecting RangeNeed to inform to supplier to arrange CPI

teams and receive the replacement yardages

Fabric Status Based on Average Point Count

3 pieces of fabric is cut away from the start , middle and end of the rolls at the inspection stage.

These Pieces are joined together as we can monitor the color shading both length wise and width wise.

Width Wise , Length Wise Color Shading Inspection

Shading Blanket

If Length wise color shading found

Inform the cutting to do 100 % numbering

If Width wise color shading found Inform to cutting and CAD room to draw and cut in grouped

markers and receive increasing YY from mill

Both length and width wise color shading found Inform the cutting to proceed with group markers and 100%

numbering.

For washed Garments , shading panel is inspected after the washing process.

Shading Panel Inspection

Skewness

Skewness is expressed as a percentage.

Measuring Skewness

x

y

Skewness = x X 100%y

Leg Twisting of garments. Side seam twisting of garments. Various shape measurement alterations in

complex garments after washing.

Effects of Skew Movement

Residual Shrinkage is used to measure the residual stress on a fabric remaining after various processes.

Residual shrinkage is measured at the time periods of 6 hours , 18 hours , 24 hours and 48 hours.

By Monitoring 0 difference between time intervals , we can decide the relaxing time of fabric.

Residual Shrinkages

Marking Shrinkage Panels

Measuring Shrinkages at the right intervals

Residual Shrinkage Report

Wash Shrinkages are done mostly for 100% rolls and is done as same as residual shrinkages, the only difference is , the shrinkages are taken after washing the pieces in the standard condition.

Not like residual shrinkages, wash shrinkages are inserted in to the computer system for the information of cutting department, patterns are adjusted according to it.

Wash Shrinkages

All below tests should pass to proceed a fabric for cutting,1. 10 % fabric inspection2. Color matching3. GSM test4. ShrinkagesAt the end of the process all passing rolls are shade vise inserted in to system for cutting.

Summary

The End