Fabric Inspection Methods | four point system | General Fabric Inspection Procedures | Types of defects found in fabric.

Fabric Inspection | four point system

Inspection: Inspection is the process required to maintain the quality of the raw materials used in the manufacture of the finished product. For garments, there is a need to check the quality of the fabric, sewing threads, trims etc. The process is followed by a specific SOP to check specific items.

Four-Point System: The most commonly used method in the garment industry for textile inspection that is followed by ASTM D5430-93 (Standard Test Methods for Visually Inspecting and Grading Fabrics). Defects are identified at a clearly noticeable distance of 3 feet and marked with dots. Each possible defect in this system has a demerit point depending on its severity.

To use this system one needs to know the following:

• Fabric Inspection Method or Preparation
• Comprehensive thoughts on the nature of fabric defects (what an error looks like and its nature)
• Criteria for awarding penalty points based on defect and length of defect
• Method for Calculation of Total Penalty Points for Total Defects Found in a Roll of Fabric or More
• a check sheet or format for recording data.

• Fabric Inspection Method: 

• The fabric is inspected to determine its acceptability from the point of view of quality. There are various textile inspection systems such as-

•    4-point system
•    10-point system
•    2.5-point system etc.

• Defect classification: 

• 4-point system assigns 1, 2, 3 and 4 penalty points according to the size, quality and importance of the defect. Not more than 4 penalty points are assigned for any one defect. A defect can be measured in either the length or the width direction; The system remains the same. Only major errors are considered. No penalty points are awarded for minor defects. Whenever errors are identified during fabric inspection under 4 point system and defect severity or length should be assigned to multiple points.

 

INCHES ( ˝ )	(MM)	POINTS
From 0 > 3″ length/width	Up to 75mm	1 point
From 3.1″ > 6″ length/width	75mm  > 150mm	2 points
From 6.1″ > 9″ length/width	150mm  > 230mm	3 points
More than 9″ length/width	More than 230mm	4 points

Only the major flaws are being taken into account. A serious defect is any defect that causes the final garment to be second.

• A linear yard can be awarded a maximum of 4 points, depending on the number and size of flaws in a given yard.
•  Four points may be awarded for each linear yard when a defect is running continuously along the length of the fabric.
•  Hole point can be evaluated by size.

HOLES AND OPENINGS (THE LARGEST DIMENSION)	POINTS
1“ or less	2
Over 1“	4

General Inspection Procedures.

• Clothing is inspected in a suitable and safe environment with adequate ventilation and proper lighting.
• The fabric passing through the frame should be at an angle of 45-60 degrees from the inspector and above the field of view on the appropriate Cool White Light 2 F96 fluorescent bulb. The back light can be used when needed.
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• The speed of the fabric on the inspection machine should not exceed 15 yards per minute.
• Standards for all accepted lots Approved bulk die lots should be available prior to the standard inspection (if possible)
• An accepted standard of bulk die lot must be available prior to initiating an inspection to assess colour, build, finish and visual appearance.
• Shade continuity within a roll and the beginning, middle and end of each roll should be evaluated and documented by examining shadow variation between center and selvage.
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• Fabrics such as knits should be rated for weight against the standard accepted weight.
• The width of the fabric should be checked from selvage to selvage against the standard.
• All defects must be marked during inspection
• The length of each roll inspected should be compared to the length mentioned on the supplier ticket tag and any deviation should be documented and reported to the mill for additional replacement to avoid shortfalls.
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• If yarn dyed or printed fabrics are being inspected, repeat measurement should be done from the beginning, middle and end of the selected rolls.
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• No penalty points are recorded or assigned for minor defects. Only major defects are considered.

• Acceptable Level:

• Many used to say that up to 40 points per 100 square yards is acceptable. In the apparel and textile industry, textile mills, apparel brands and buyers set their own standards for acceptable points. A standard level is set by the ASTM.

• Many mills grade the fabric rolls or fabric lots as first quality and second quality rather than pass/fail. Re-grading is done based on the number of penalty points per 100 square yards.

• Another thing you should remember is that acceptable points can be defined as points per 100 linear yards as well as points per 100 square yards. Secondly, the admissible marks for different rolls and admissible average marks for all the rolls are determined at different levels.

• An international buyer who explains something like the following

• Any defect running more than 4 yards in a row will result in rejection of the roll.

• Fabric widths up to 64-66 inches will be classified as quality first if the number of penalty points does not exceed 50 points per 100 linear yards.

The admissible penalty points should be in the ratio of 50 marks per 100 linear yards for widths of fabric more than 64-66 inches. (Use 64 inches for such calculations)

In general, acceptable levels of 'points per 100 linear yards' or 'points per 100 square yards' vary for different fabric types. for example:

Cotton Twill / Denim 28 points per 100 square yards (23 dots per 100 square meters) for individual fabric rolls

20 points per 100 square yards (16 points per 100 square meters) for individual fabric rolls for all synthetic fabrics

Example: A roll of fabric 120 yards long and 46 inches wide has the following defects.

DEFECTS	DEFECTS POINT
4 defects up to 3 inch length 3 defects from 3 to 6 inch length 2 defects from 6 to 9 inch length 1 defect over 9 inch length 1 hole over 1 inch	4 x 1 3 X 2 2 X 3   1 X 4 1 X 4	4 points 6 points 6 points 4 points 4 points
Total defect points		24 Points

                                              =15.652. So, defect is acceptable.

Check sheet or Inspection Format                                                              

 

A simple check sheet should be used to record or collect defects during the inspection. A check sheet contains general description, description of fabric lots, fabric defects as per their size, summary of fabric defects, quantity inspected and total penalty points and result of fabric lot after inspection. Use tally marking for recording the number of defects. A sample 4 point system fabric inspection format is attached below.

Types of defects found in fabric.

The fabric checker should know the common defects found in the fabric and identify the defects on the fabric at the time of fabric inspection. Some fabric defects are given below:

A major defect is any defect which, if found in the finished fabric/garment, will classify that fabric/garment as Class II.

MAJOR WOVEN FABRIC DEFECTS	SLUBS, HOLE, MISSING YARN, CONSPICUOUS YARN VARIATION, END OUT, SOILED YARN, WRONG YARN.
Major knitted fabric defects	mixed yarn, yarn variation, runner, needle line, barre, slub, hole, and press off.
Major dye or printing defects	out of register, dye spots, machine stop, color out, color smear, or Shading.

 

The Quality Inspector may include any other defects which he feels to be of a major category and may forward such defect details to the customer for feedback, if required.

Minimum allowable width.

This width is excluding selvage. The width of the fabric shall be checked at least three times during the inspection of a piece (beginning, middle and end of a piece). Pieces with a measurement width less than the specified purchased width will be classified as second quality.

Fault Rule:

• For each linear meter or yard in which it occurs, a continuous fault will be assigned four points.
• Any piece that is more than three continuous linear meters or so running through the yard will be rejected. Even though in point count.
• Any piece with a full width defect of more than six inches will be rejected.
• Any piece that has more than three full-width defects per hundred linear meters or yards shall be rejected.
• No piece shall be accepted which has the defect of full width in first and last three meters or yards.
• A hole or torn is considered a major defect and shall be punished with four
• Fabric construction and weight, no tolerance will be allowed.
• The distance between major faults should be more than 20 meters.
• All major and full width defects should appear to be a polyester thread on the selvage.
• Wavy, tightness, ripples, puckering in the body of the fabric that prevents the fabric from being flat when stretched in the traditional way are not acceptable.

Penalty will be imposed on the following offenses as per rules:

Kinks, knots, slubs, contamination, spots, and half/double pick, cocked yarn, coarse pick. Heavy weight bar less than 6" in length, set mark, wrapping, broken pick, out mark, hole and float up to "

The following defects are cut tables and will be rejected:

• Frequent kinks, knots, slubs, contamination, spots etc.any persistent fault
• More than one meter broken end, double end, wrong draw reed mark
• The holes burst and floated up"
• Irregular Selvage, Light Weight Bar, Count Variation, Leco, Shade Variation
• Over 6 Heavy Weft Strips: In Length
• The most commonly used system is the American 4 point system.
• The ASTM D5430 standard describes how to assign marks to each defect—mostly based on its size.
• The overall result consists of two numbers (and those are all buyers want to know about defects):
• Average number of points for all inspected rolls (based on 100 meters),
• Ratio of rolls exceeding the acceptance limit.

Maximum allowable marks = 20 marks per 100 square yards or 22 marks per 100 square meters.