Function: The instrument is used for visual inspection of yarn like neps, thick and thin places etc.
The textile industry uses vegetable fibers (such as cotton), animal fibers (notably wool and silk), and a wide range of synthetic materials such as nylon, polyester, and acrylics. The production of natural fibers is approximately equal in amount to the production of synthetic fibers. Polyester accounts for about 50 percent of synthetics. (Chemical production of the polymers used to make synthetic fiber is not covered in this document.) The stages of textile production are: fiber production, fiber processing and spinning, yarn preparation, fabric production, bleaching, dyeing and printing, and finishing. Each stage generates wastes that require proper management.
The garments industry uses processed fabrics from textiles as their raw material. They have a wide range of products like readymade Shirts, T-shirts, Trousers, , etc. The stages of value addition for garments industry are : Sample and Marker making, Cutting, Sewing, Finishing, and Packing and Carton Making. Like textile industry, even these stages generate wastes during processing. Necessary action is required to control and dispose these wastes.
Textile production involves a number of wet processes that may use solvent and other volatile organic compounds (VOCs). Process wastewater is a major source of pollutants. It is typically alkaline and has high BOD5 (700 to 2000 mg/1) and COD (approximately 2000 mg/1), solids, oil and possibly toxic organic, and phenols form dyeing and finishing. Dye waste waters are frequently highly coloured and may contain heavy metals such as copper and chromium. Wool processing may release bacteria or other pathogens.
Thus, the small fabric parts generated during cutting procedure or the yarn particles or fluffs generated during further processing like sewing, inspection or finishing, are the main wastes of garments industry.
Written By - Robert Dkay, Manager, Golder Accessories Ltd. Narayangong
Yarn Examining board is used for visual inspection of textile yarn like naps, thick and thin places.
Yarn Examining Board Specification
Product Category: QC Yarn
Machine Category: Yarn
Product Name: Yarn examining board.
Product Model:According to Manufacturer
Product Class: New
Origin: Made in China / America
Brand/ Manufacturer: Name of Manufacturer
Agent in Bangladesh: No/Yes
Power:380v, AC220V±10% 50HZ.Power:55W
Temperature:Normal
Certification:SGS/Others
Production Capacity:NA
Density of reeling:7,9,11,15,20/cm 20/45mm
Pressing by grade.,Seven yarn grade: 7,9,13,15,19/cm and GB/T399 standard density
Rotate speed of show board:350r/min with staples speed adjustment
Yarn Mixing
Average Micronaire of mixing should be same for entire lot & difference in average micronaire of different mixings of same lot should not be more than 0.1.
The micronaire C.V% of a mixing should be less than 10%.
The micronaire Range should be same.
Cottons with two different origins should not be mixed.
Cottons with too wide micronaire range should not be mixed.
Cottons with too wide reflectance value (Rd) and Yellowness value (+b) should not be mixed.
Immature fibre content should be lowest as it affects dyeing & results in white-specks.
If automatic bale openers are used, bale lay downs should be done properly, so that different micronaire bales & colours are getting mixed up homogeneously even if small quantity is being checked.
If manual mixing is carried out, bales should be arranged & mixed properly so that different micronaire bales & colours are getting mixed up homogeneously even if small quantity is being checked.
For manual mixing, tuft size should be as low as 10gm.
If contaminated cottons are used, the best way is to open bales into small tufts & segregate contaminants. There are mills that employ around 60-80 persons to pick up contamination from a mixing of 20tons.
Japanese insist on mixing at least 36 bales for one mixing to avoid Barre problem.
The fabric examining machine with variable speed control, overhead light (daylight bulbs) and yardage counter. The machine must be clean with no oil and sharp edges to damage the fabric.
How much fabric to inspect
The garment making factory should inspect 10% of rolls from each delivery at random this should include all colors and dyelots within a delivery. If the results show a high fault rate, then an additional 15% rolls should be inspected. If these fail, the delivery is either rejected or 100% inspected.
Procedure
At the beginning of each roll, a 6” full cutting should be taken as a color reference and checked for side-to-side and side-to-center shading.
This is labeled with fabric reference number or name, batch number, piece number, color number, color name and date.
Width of the fabric between the stenter pins must be measured and compared with the given minimum usable width.
Each roll checked must be stopped at least 3 times during inspection (beginning, middle, end). At these points, side-to-side and side-to-center shading should be assessed.
Side-to-end shading must be checked by comparing the full width cutting to a point in the roll. Also the cutable width (between the stenter pins) should be measured.
The cutable width should be recorded on the inspection report, as should any color shading detected.
Check the fabric length stated on piece ticket against the actual length of roll for variance. Record both the values.
Allotment of points on 4-point system
Flaws
Points given
Up to 3″
1
3″-6″
2
6″-9″
3
More than 9″
4
Points/yards2=Actual points counted x 36” x 100
Actual roll length Actual width
Common Defects in various points scheme
1 Point
2 Point
3 Point
4 Point
Foreign Yarn
Weaving faults
Weft Bar
Thick Yarn
Slub
Foreign Yarn
Thick Yarn
Hole
Spot
Thick Yarn
Weaving Fault
Shade Bar
Weaving Fault
Missing Yarn
Missing Bar
Dyeing Effect
Shade Bar
Missing Yarn
Naps
Thick Yarn
Apart from these defects, the fabric is also tested for shrinkage, color fastness, and the shade variation (through light box), within a roll and between two rolls.
Fabric:
1. Are all colours affected? If not which ones are? 2. How many points did the 4pt. inspection come up to? 3. Is/are the sample(s) sent representing the: – worst – average – best 4. Is/are the cutting(s) sent taken from the: – beginning – middle – end of the roll ? 5. Are all rolls or what batches are affected? 6. Is every yard affected or how often do they repeat? 7. Are the faults of this cutting typical for size & severity? 8. Based on your experience do you think the fabric is cuttable? 9. Please advise estimated loss (e.g. in percent).
In case of fabric faults please cut & send 1yd (not from the first 5yds) of 10% of the rolls but no more than 7. In case of shading please cut & send 20cm x full width (not from the first 5yds) of every roll. Garments: 1. Are all colours affected? 2. Is the shirt from bulk production? 3. Is it representing the: – worst – average – best of production ? 4. How many shirts are affected (e.g. percent)? 5. Can these faults be avoided on collar, cuff & A zone? 6. In case of shading is this caused by: – roll to roll shading and therefore mix of panels – shading within the same roll – shading of interlining
