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QUALITY CONTROL
by
M.Amsaveni, Assistant Professor, Dept. Costume Design and Fashion,
Kongunadu Arts and Science College, Coimbatore.
Apparel Quality Inspection and Standards
Testing: Testing means checking, examine and verification of some items. On the other way we can define testing as; it is the process or procedure to determines the quality of a product.
Objects of Quality Control:To produce required quality product.To fulfill the customer's demand.To reduce the production cost.To reduce wastage.To earn maximum profit at minimum cost.
Quality means customer needs is to be satisfied. Failure to maintain an adequate quality standard can therefore be unsuccessful. But maintaining an adequate standard of quality also costs effort.
"The systems required for programming and coordinating the efforts of the various groups in an organization to maintain the requisite quality".
In the garment industry quality control is practiced right from the initial stage of sourcing raw materials to the stage of final finished garment. For textile and apparel industry product quality is calculated in terms of quality and standard of fibres, yarns, fabric construction, colour fastness, surface designs and the final finished garment products.
Quality Control:
Total Quality Control:"To ensure that the requisite quality of product is achieved". This ensures customer satisfaction, but it leaves quality control as a necessary but expensive evil.
To ensure, at minimum practicable cost, that the requisite quality of product is being achieved at every stage of manufacture from raw materials to boxed stock
Objectives:To maximize the production of goods within the specified tolerances correctly the first time.To achieve a satisfactory design of the fabric or garment in relation to the level of choice in design, styles, colours, suitability of components and fitness of product for the market
Textile Quality Control Experts:Quality Control: AQM performs quality control and inspection services for different customers from all over the world. Using international standards such as ISO 2859, our Quality Controllers (QC) method consists to check different control points:
Conformity: The QC checks the conformity of the product (design, colors, raw material…) with the Pre-Production Sample (PPS) and other technical files.Quality: Our QC checks for defects (fabric defects, colors defects, accessories and label defects, manufacturing defects) and classifies them accordingly.Measurement: Following the measurement chart, our QC checks the measures for each size of the product.
Packaging: Our QC checks the quantity of cartons, size of cartons, their weight, shipping marks, etc.
What is Quality Control in Textiles?Quality control is a set of steps or guidelines designed to guarantee that a product or service meets certain performance standards. The goal of quality control is to ensure that an item meets the needs and specifications of the consumer population. Good quality control also helps a company to more efficiently navigate manufacturing and production processes to cut down on mistakes and waste, and maximize profit.In the textile industry, quality control is not much different than the standard definition provided here. It is a program put into place from the very beginning of the textile manufacturing process, starting from the sourcing of raw fibers to the final stages of garment production.Textile quality control is measured by a garment's quality as well as the various production components:
• Selection of raw materials• Fiber manufacturing• Yarn manufacturing• Fabric construction• Dye and coloration• Printing and designs• Finishing components such as zippers or embellishments
Way of control quality:
Have the proper approach toward operators.• Train the operator to sew with good quality from the beginning.• Know quality specifications and tolerance. Be sure you understand what constitutes good and poor quality. Be consistent in your decisions toward quality.• Comment on both good and bad quality. We all have a tendency to be silent during good times and vocal during the bad.• Be sure to check each operators work daily.• Use a check list. Do not rely on memory of specifications.• Do not rely on inspectors to tell you the quality level of your operators, instead find out yourself.• Do not have a compromising attitude towards problem related to quality.
Garments Inspection
The inspection that is done for controlling the quality of garments
is mainly meant to examine in bare eyes. Checking of the fabrics of garments, sewing, button, thread, zipper, measurements of
garments etc. with the standard process is called the inspection.
In each section of a garments industry, there are arrangements for
inspection. The main purpose of inspection is to identify the faults
at the earliest possible steps for production of garments and
earlier the defects will be detected lesser will be the wastage of
time and money.
For conducting successful and meaningful inspection, steps can be adopted as per the ‘inspection loop’ described below. First,
identify defects through inspection, inform about the defects to the
concerned person, identify the causes of defects, and rectify
them.
Garments Inspection Steps
In garments Industry, inspection is generally conducted in three steps:
•Raw material
•In Process and
•Final
Raw material Inspection
In garments industry, raw material means mainly the fabrics, but sewing
thread, zipper or chain, interlining etc. also may be considered under the
items of raw material.
Fabric Inspection
Just the moment for production of garments, fabric is required, which is the
main element of garment. Local or foreign that means whatever be the
country of origin of fabrics, the quality of fabrics should be well judged
before purchasing of fabrics, because, if not so, both time and money may
be wasted. Specially, due to the low grade fabrics, burden of irreparable
loss may have to be borne. Some factories do inspection after reaching the
fabrics at their factories. But it is wise to do the fabric inspection at sellers
factory.
Sewing thread Inspection
Frequent breaking of sewing threads during sewing of garment indirectly influences
on the production of garments and its quality. It is necessary to mention here that in
running condition of machine, the sewing threads run through the needles at a speed
of 140 to 165 K.M per hour. The strength of thread may be decreased from 2 to 32%
due to the friction of threads with the various parts of machines and fabrics. For this
reason, before purchasing of sewing threads, the below mentioned characteristics of
threads should be verified –
•Ticket number
•Sewability\
Chain (Zipper)
Chain or zipper is a special part of a garment, which if defective, the garment may be
unfit for wearing. Need to be ensured beforehand about the below issues so that the
defects related to the zippers should not arise.
•Dimension
•Stops
•Uniform color
•Puckering
•Slider
•Lock
•Arrow mark
In-Process Inspection
The process of inspection of the various parts of a garment
before joining is called in-process inspection. In garments
industry, inspection is done in each section starting from
spreading to finishing. The main objective of in-process
inspection is to identify the defects in the primary stages of
various sections and to adopt the necessary steps to rectify
the defects. Because, the defects detected as earlier, its
rectification cost will be lesser. In order to control the quality of
garments, the measures that can be adopted in the steps of
garments making, are discussed below in steps:
Marker making
If mistakes or defects occurred in marker making, the quality of
garments will be lower. So all the matters involved in marker
making, should be inspected properly. As for example, need to
examine whether the labeling or code numbers have been
placed properly in each of the patterns drawn in the marker.
Fabric SpreadingThe defects during spreading of the fabrics, for which the
quality of garments may be lower, should be taken care at the
time of spreading of fabrics. As for example, during
spreading, fabric should be spread as per the length and
width of the marker and the edges of fabric both in the
directions of length and in width have to be aligned.
Otherwise, the wastage of the fabric will increase.
Fabric Cutting
The most important precondition for making of high quality
garments is the cutting of fabrics in high quality. So the
factors related to fabric cutting, should be inspected carefully.
As for example, whether the dimension of the patterns and
the cut fabrics are exactly same or not should be inspected.
Fabric Sewing
In garments manufacturing industries, the most specious and the
most important section is the fabric sewing section. The jobs of
each sewing machine operator of this section should be regularly
inspected, and specially, it is to be specified that up to what level
of faults in each job is acceptable, and always arrangements
should be made for identifying the defects through inspection, and
to adopt measures for rectifications, and to control the defects.
Pressing or FinishingThe main objective of pressing or finishing is to make arrangement
so that garments look good, because, in most of the cases a
customer takes the buying decision of the garment based on
whether it looks good or not though buying of a garment also
depends on its price, quality, standard etc. For this reason,
pressing or finishing is very much important.
Final Inspection
In the final inspection, mainly the whole inspection of
garments is done, because, before this stage, there is no
opportunity to do inspection of a complete garment. This
final inspection is very much important from the buyers
end. In this final inspection, mainly the size of the
garments, form fitting, and the defects of the garments
are inspected.
Final Inspection of Garments Quality:
The supplier must perform an internal quality inspection
before offering the lot to the manufacturer QA Auditor. To
confirm the product quality, use the AQL sampling
plan table and follow these steps-
1. Establish the number of units in the consignment.
2. Use the AQL table to determine the number of units to
be inspected.
3. Randomly select the sample quantity from across the
sizes and color.
4. Check the sample lot quantity for all quality performance
standards (i.e. Packing Standards/ Function and Testing
Standards/Visual Standards).
S/L Section Criteria
01 Presentation
Do the goods meet retailing standards?
Are the garments crushed, creased or glazed?
Are the garments soiled, stained or wet?
02 Labeling
Is there a correct logo?
Is there a correct size label?
Are there correct labels on fiber content and wash care instructions?
Are the bar-code tags or swing tickets incorrect or missing?
03
Components and
Trims
Are the components or trims rusting, tarnishing or broken?
Are there incorrect attachments (for example handles)?
Are the zippers faulty or incorrect?
Are the tie cords correct?
04 Make Up
Are the seams insecure, puckered, grinning, roping or twisting?
Is there needle damage (includes laddering)?
Are there excessive threads or is there poor trimming?
Are the collars, pockets, zippers or darts incorrectly sewn or panels
misaligned?
Final Inspection Check List:
When goods are received at manufacturer warehouse/RDC, they are assessed using the
checklist below. The inspection will be based on ISO 2859, BS 6001, ANSI /ASQC 1.4:1993
and JIS Z 9015-1.Garments manufacturer always recommends that inspection before
presenting the goods for final inspection. This is particularly important for Export
orders where the goods by-pass warehouse/DC processing.
05 Fabric faults
Are there printing or dyeing faults?
Are there faults in the fabric or interlining?
Is there varying shading within the garment?
Is there varying shading from garment to garment?
06 Miscellaneous
Is the garment measurement within acceptable tolerance
as defined in the Gold Sample / Design Pack?
Are the correct numbers of spare buttons provided?
Did all colors passed all required Laboratory Testing
Procedures?
Did it meet all government regulatory requirements?
Did it meet all safety requirements?
Fabric Inspection Method:
Fabric is inspected to determine its acceptability from a quality view point.
There are various fabric inspection system such as-
•4- point system
•10- point system
•2.5- point system etc.
4- Point System:
The 4- point system is widely used for fabric inspection, in the united states it
is known as AAMA point grading system (AAMA- American Apparel
manufacturers association).
Procedure of Four Point System:
•Fabric inspection is usually done on fabric inspection machineries.
•These machineries are designed so that rolls of fabric can be mounted behind
the inspection table under adequate light and re-rolled as they leave the table.
•Inspection machineries are either power driver or the inspector pulls the fabric
over the inspection table.
•The defects are located, marked and recorded on an inspection form.
•Some machinery is equipped to measure the length of each roll of fabric
(meter/yard).
Length of defect in Fabric Points allotted
Up to 3 inch 1
Over 3 inch up to 6 inch 2
Over 6 inch up to 9 inch 3
Over 9 inch 4
Holes and Opening
1 or less 2
Over 1 inch 4
Fabric defects point values based on the following:
Calculations and Result:
Total defect points per 100 yard square are calculated.
If fabric rolls contains less than 40 points per 100 yard square are
considered “first” quality and as an Acceptance criteria.
If fabric rolls containing more than 40 points per 100 yards square are
considered “second”.
Example:
A fabric roll 130 yard long and 45 inch wide contains the following defects:-
6 defects up to 3 inch- ...................................6 X 1 = 6 points
5 defects over 3 inch but less 6 inch- ............. 5 X 2 = 10 points
2 defects over 6 inch but less 9 inch- ..............3 X 2 = 6 points
1 defects over 9 inch- ....................................1 X 4 = 4 points
1 hole over 1 inch dimensions- .......................1 X 4 = 4 points
Total defect points................................................= 30 points
Therefore,
Points per 100 yard square =
Total points scored in roll X 36 inch
……………………………………………………………… X 100
Fabric width/inches X Total length yard inspected
30 X 36
= ……………………… X 100
130 X 45
= 18.4 (Defect points per 100 yard square.)
So, the roll is Accepted.
10 Points SystemFor production of high quality garments, need high quality piece goods. It is an universal
truth. When a sewing factory receives fabric from the mill, it is difficult to conduct a full
100% inspection of the fabric. So then minimum 10% inspection of all piece goods prior to
spreading the fabric. There are several methods of fabric inspection in garments industry.
Ten Points system is one of them.
The 10 point method is a point per fault system, which gives a measurable guide to quality
grading per roll. In 1955s “Ten Points” piece goods evaluation was adapted by the Textile
Distributors and National Federation of Textiles. The system assigns penalty points to each
defect as per following guideline.
Warp Defects
Size of defects →→→→→→→→→→→→→→Penalty
•Up to 1 inch →→→→→→→→→→→→→1 Point
•1 to 5 inches →→→→→→→→→→→→→3 Points
•5 to 10 inches →→→→→→→→→→→→5 Points
•10 to 36 inches →→→→→→→→→→→10 Points
Filling/Weft Defects
Size of defects →→→→→→→→→→→→→Penalty
•Up to 1 inch →→→→→→→→→→→→ 1 Point
•1 to 5 inches →→→→→→→→→→→→3 Points
•5 inches to half the width →→→→→→5 Points
•Half to Full width →→→→→→→→→→10 Points
A maximum 10 Points is charged for one linear yard of fabric.
Working Procedures•Under the 10 Points system, a piece is graded as “First”, if the total penalty points do not
exceed the total yardage of the piece.
•In case of a fabric wider than 50 inches; “First” quality is considered if the total defect points
do not exceed the total yardage of the fabric.
•A piece is graded as “Second” if the total penalty points exceed the total yardage of the
piece.
Graniteville “78” system:The system assigns penalty points to each defect as per following guideline.
For either Length or Width
Size of defects→→→→→→→→→→→Penalty
•Up to 9 inches →→→→→→→→→→→1 Point
•9 to 18 inches →→→→→→→→→→→2 Points
•18 to 27 inches →→→→→→→→→→→3 Points
•27 to 36 inches →→→→→→→→→→→4 Points
The maximum penalty points per linear yard that can be assigned are determined by
dividing the fabric width in inches by 9.
Therefore,
Maximum penalty points for 48 inches wider fabric = 48/9 = 5.33 or 6.
Maximum penalty points for 60 inches wider fabric = 60/9 = 6.33 or 7.
The maximum penalty point per square yard is 4.
Dallas SystemThis system was developed in 1970s specifically for knits. It was approved by Dallas Manufacturers Association. According to this system, if any defect was found on a finished garment, the garment would then be termed as a "second". For fabrics, this system defines a second as "more than one defect per ten linear yards, calculated to the nearest ten yards". For example, one piece 60 yards long would be allowed to have six defects.
General Inspection Procedures•Fabric inspection is done in suitable and safe environment with enough ventilation and proper lighting.•Fabric passing through the inspection frame must be between 45 - 60 degree angles to inspector and must be done on appropriate Cool White light above viewing area. Back light can be used as and when needed.•Fabric speed on inspection machine must not be more than 15 yards per minute.•All fabric inspection must be done when 80% of good or lot is received.•Standard approved bulk dye lot standards for all approved lots must be available prior to inspection.•Approved standard of bulk dye lot must be available before starting inspection for assessing colour, hand, weight, construction, finish and visual appearance.•Shade continuity within a roll by checking shade variation between centre and selvage and the beginning, middle and end of each roll must be evaluated and documented.•Textiles like knits must be evaluated for weight against standard approved weight.•Fabric width must be checked from selvage to selvage against standard.•All defects must be flagged during inspection.•The length of each roll inspected must be compared to length as mentioned on supplier ticketed tag and any deviation must be documented and reported to mill for additional replacement to avoid shortage.•If yard dyed or printed fabrics are being inspected the repeat measurement must be done from beginning, middle and end of selected rolls.
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