An investigation on the inspection of grey & finished knit fabric in wet processinge

PROJECT ON
An investigation on the inspection of grey &
finished knit fabric in wet processing

SOUTHEAST UNIVERSITY
SOUTHEAST UNIVERSITY
WELCOME TO OUR
PRESENTATION

Company profile
Name of the Company: Aman Tex Ltd
Year of Establishment: 2009
Manufacturing products: Export oriented knit fabrics dyeing and readymade garments
Owner and directors of the factory: MD. RAFIQUL ISLAM
Factory Address: Boiragirchala ,Sreepur Gazipur, Bangladesh
Total Employees: 5900
Number of units: 4 (Four) units
Part-A: Knitting unit
Part-B: Dyeing unit
Part-C: Garments unit – 3 floors
Part-D: Printing unit
Total area: 271,000 square feet.

INDRODUCTION
After fabric is received, inspection should be done to determine its
acceptability from a quality view point; otherwise extra cost in
garment manufacturing may be returns and dissatisfaction due to
poor fabric quality. Either way fabric inspection after the fabric
production process will release the burden responsibility at the
marking, spreading and cutting section. As a result a spreader will
be concentrating more in spreading rather to worry about fabric
inspection and detecting faults.

Aim of the project
1. Research.
2. Analysis various inspection Fault in different process of
wet processing and find out the remedial measure.
3. Product testing.
4. Product Quality improvement.
5. Reduce wastage.
6. To maximize the production.
7. To minimize the production cost.

Inspection Machine
Fabric inspection is usually done on
fabric inspection machines such as
those shown in the Figure. These
machines are designed so that
fabric rolls can be mounted behind
the inspection table under adequate
light and rerolled as they leave the
table. This inspection m/c is either
power driven or the inspector pulls
the fabric over the inspection table.
The defects are tracked, marked and
recorded on an inspection sheets

Fabric Inspection
When, why, where
Producer likes to know the quality of his products (says quality for 500,000 yds fabric)
Buyer wants to assure the product quality he ordered.
10% check will give buyer some ideas of his product quality
25% check maybe necessary for new supplier
3% check maybe enough for a proven record supplier
Fabric inspection must be selected randomly
The fabric sample must be selected from different place, different lot and different
time
Inspector must use a packing list and select different bales on different place
The samples should be selected from early, middle and late production.

Inspection Standards
1. Ten Point System
 Oldest and most used in woven finished fabric
2. Four point System
 Widely adopted and used in knitted fabric
3. The Graniteville’78 System
 major and minor types, used in garment pieces
AMAN TEX LTD (KNIT COMPOSITE) - All inspection 4 point system

Grey Fabric Inspection
Grey fabric inspection is the
process of identifying
knitting faults in the knitted
fabric just after the grey
fabric production in the
knitting machine

Four Point System
Four Point System is adopted by American Apparel Manufacturers Association
(AAMA) for piece goods knitted fabric. Fabric defects is penaltized by maximum
of 4 points.
In this system fabric faults are identified with defect points in the scale of 4. I.e.
maximum defect point is 4.

Four Point System
Calculation:
Such as point =12
WTX1000X39.37 23.82X1000X39.37
MTR = = =52M
F/G X F/D 380X47
POINTX100X39.37 16X100X39.37
TOTAL POINT = = =25 (B)
F/DXMTR 47X52

Grey Fabric Inspection Repot of Aman Tex Ltd

Grey Fabric Inspection Faults
1. Needle Mark
2. Needle Broken
3. Hole Mark
4. Pin Hole
6. Drop Stitches
7. Bariness
8. Loop
9. Lycra Out
5. Star Mark 10. Seat Up

1. Needle Mark
Causes:
1. When a needle breaks down.
2. If a needle or needle hook is
slightly bends .
3. If needle does not catch yarn .
Remedies:
 Needle should be straight as well
as from broken latch.

2. Needle Broken
Causes:
•High Yarn Tension
•Bad Setting of the Yarn Feeders
•Old & Worn out Needle set
Remedies:
Ensure uniform & the right Yarn
tension on all the feeders.
Keep the recommended gap,
between the Yarn Feeders & the
Needles.
Periodically change the complete set
of needles.

3. Hole Mark
Causes:
Yarn breakage or yarn cracks.
If the yarn count is not correct on
regarding structure, gauge, course and
density.
Badly knot or splicing.
Yarn feeder badly set.
If yarn tension too high
Remedies:
Yarn strength must be sufficient to
withstand the stretch as well as uniform.
Use proper count of yarn.
Correctly set of yarn feeder.
Knot should be given properly.

4. Pin Hole
Causes:
Improper tension.
Same drive for both knit & tuck stitch.
Curved needle latch.
Remedies:
Different drive have to maintained
Needle has to change.
Needle has no change.

5. Star Mark
Causes:
Yarn tension variation during production.
Buckling of the needle latch.
Low G.S.M fabric production.
Remedies:
Maintain same Yarn tension during
production.
Use good conditioned needles.

6. Drop Stitches
Causes:
Defective needle.
If yarn is not properly fed during loop
formation i.e. not properly laid on to the
needle hook.
Take-down mechanism too loose.
Insufficient yarn tension.
Badly set yarn feeder.
Remedies:
Needle should be straight & well.
Proper feeding of yarn during loop
formation.
Correct take up of the fabric & correct fabric
tension.
Yarn tension should be properly.

7. Bariness
Causes:
Use of irregular yarn having higher
long term irregularities.
Using different count thread.
Remedies:
Remove irregular yarn.
Use proper yarn count.
We can use it for white fabric.

8. Loop
Causes:
If needle latch is hard or curve.
If yarn tension is loose.
Remedies:
Clean or change the needle.
Set proper yarn tension

9. Lycra Out
Causes:
Cause by If lycra is missed
or Lycra attach with the yarn.
Remedies:
Check the feeder and attach
lycra.

10. Seat Up
Causes:
If needle latch is not work properly.
Causes by thick yarn.
Improper/large knot.
Remedies:
Make sure all the latches of needle
are closed with feeding yarn after a
drop stitch.

Finished Fabric Inspection
Finished inspection is done
after dyeing and finishing
process to find out the dyeing
and finishing faults, calculate
the number of faults ,grading
and taking decision to accept
or reject a finished fabric roll.
In AMAN Tex, 4 point system
is followed for finished fabric
inspection.

Finished Fabric Inspection Repot of Aman Tex Ltd

1. Uneven Dyeing
3. Soda Spots
4. Fabric hole
5. Compacting hole
6. Crease Mark
7. Dark Colored oil Spots
8. Softener Mark
9. Batch to Batch Shade variation
10. Roll to roll variation
11. GSM Variation
2. Dye spot

Finished Fabric Inspection Faults
1. Uneven Dyeing
Sources & Causes:
Uneven pretreatment (uneven scouring & bleaching).
Improper color dosing.
Using dyes of high fixation property.
Uneven heat-setting in case of synthetic fibers.
Lack of control on dyeing m/c.
Effects:
 Dyeing process loss.
Fabric waste in garments section.
More time.
Waste of chemical & dyes.
More water & steam.
Remedy:
By ensuring even pretreatment.
By ensuring even heat-setting in case of synthetic fibers.
Proper dosing of dyes and chemicals.
Proper controlling of dyeing m/c.

2. Dye spot
Sources & Causes:
Improper Dissolving of dye particle in bath.
Improper Dissolving of caustic soda particle in bath.
Effects:
Body fabric rejected in the garments section.
More dye & caustic.
More fabric damage.
Less production.
Cost highly.
Remedies:
By proper dissolving of dyes & chemicals.

3. Soda Spots
Sources & causes:
Soaping start before wash.
CaCO3 or MgCO3 in soaping bath.
Remedy:
Remove hardness water
Use sequestering agent

4. Fabric hole
Sources & causes:
More acid of knit fabric in the dyeing section.
Highly acidity.
Temperature highly.
Effects:
Damage of the knit fabric.
Fabric strength, stiffness & comfortable loss.
Waste of acid.
Loss Time & Temperature.
Remedy:
Use standard Acid.
Proper dosing of Acid.
Proper Control of dyeing m/c.
Temperature Control.
Proper acid addition.

5. Compacting hole
Sources & Causes:
More steam pressure.
Low roller RPM .
Uneven roller.
Remedies:
 Proper steam pressure.
Proper roller RPM.
Feeding the even roller in compacting m/c.

6. Crease Mark
Sources & Causes:
Poor opening of the fabric rope.
Shock cooling of synthetic material.
If pump pressure & reel speed is not equal.
Due to high speed m/c running.
Remedy:
•Maintaining proper reel sped & pump speed.
•Lower rate rising and cooling the temperature.
•Reducing the m/c load.
•Higher liquor ratio.

7. Dark Colored oil Spots
Sources & Causes:
Often encountered when the goods are given
silicone finishing agent treatment in soft flow
machine using SILICONES which are NOT jet
stable.
Remedies:
Use jet-stable silicones.

8. Softener Mark
Sources & Causes:
Improper mixing of the Softener.
Improper running time of the fabric during
application of softener.
Entanglement of the fabric during application of
softener.
Remedies:
Maintaining proper reel sped & pump speed.
Proper Mixing of the softener before addition.
Prevent the entanglement of the fabric during
application of softener.

9. Batch to Batch Shade variation
Sources & Causes:
Fluctuation of Temperature.
Improper dosing time of dyes & chemicals.
Batch to batch weight variation of dyes and chemicals.
Dyes lot variation.
Improper reel speed, pump speed, liquor ratio.
Improper pretreatment.
Remedies:
Use standard dyes and chemicals.
Maintain the same liquor ratio.
Follow the standard pretreatment procedure.
Maintain the same dyeing cycle.
The pH, hardness and sodium carbonate content
supply water should check daily.

9. Roll to roll variation
Sources & Causes:
Poor migration property of dyes.
Improper dyes solubility.
Hardness of water.
Faulty m/c speed, etc.
Remedies:
Use standard dyes and chemicals.
Proper m/c speed.
Use of soft water.

11. GSM Variation
Causes:
Roll to roll variation in the, process parameters, of
the fabric, like; Overfeed & Widthwise stretching of
the dyed fabric, on the Stenter, Calander &
Compactor machines.
Roll to roll variation in the fabric stitch length.
Remedies:
 Make sure that all the fabric rolls in a lot, are
processed under the same process parameters.
 The Knitting Machine settings, like; the Quality
Pulley diameter etc. should never be disturbed

CONCULATION
In Bangladesh most knit dyeing industries are suffering from these above
inspection faults. So they faces high production cost & not fulfill the target of
production. We observed the grey & finished inspection process at our intern
period .We also tried to observe the grey & finished inspection faults , causes of
the faults & tried to find out the remedies of the faults. If an industry follows these
above remedy measures , it can minimize its production cost and improve
quality, productivity and acceptability. We believe that, this project will help us in
our future career and we are very hope full that we can utilize this knowledge I
our practical job life.

An investigation on the inspection of grey & finished knit fabric in wet processinge

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An investigation on the inspection of grey & finished knit fabric in wet processinge