1. Faults in Knit Dyed Fabric

2. Name : MAZADUL HASAN SHESHIR
ID: 2010000400008
Batch: 13th Batch (Session 2009-2013)
Department: Wet Processing Technology
Email: mazadulhasan@yahoo.com
Blog: www. Textilelab.blogspot.com
Southeast University
Department of Textile Engineering
PREPARED BY ©right

3. Knitting faults

4. Yarn dust
Causes of faults: -
 Fly yarn/ foreign fiber
Remedies: -
 Proper air suction

5. Set-up
Causes of faults: -
 For badly needle break
 Yarn break
Remedies: -
 Remove bad needle
 Maintain proper tension

6. Loop mark
Causes of faults: -
 Defective needle
 Not properly needle latch
work
Remedies: -
 Change new needle
 By clean needle latch, hook

7. Needle break
Causes of faults: -
 High yarn tension
 Bad setting of the yarn
feeders
 Old and worn out needle
set
Remedies: -
 Ensure uniform and right
yarn tension on the feeders
 Keep the recommended
gap between the yarn
feeders and the needles
 Periodically change
complete set of needles

8. Oil spot
Causes of faults: -
 Due to contact with oil or
grease covered exposed
m/c parts
 Careless handling could be
another cause
Remedies: -
 Use of strong knitting oil
which can be removed
 After every process, if
possible check filter and
clean it

9. Thick place
Causes of faults: -
 Different yarn count
 Use unmatured fiber
Remedies: -
 Select matured fiber
 Check /indentify the yarn
thick/thin place

10. Mix yarn/Lot mix
Causes of faults: -
 Unawareness of operator
Remedies: -
 Awareness in production

11. Hole
Causes of faults: -
 Holes are the results of
yarn breakage
 Yarn tension too high
 Presence of knots in yarn
 If the yarn count is not
correct
Remedies: -
 Yarn strength must be
sufficient
 Maintain proper tension
 Knots should be given
properly
 Use proper count of yarn

12. Lycra out
Causes of faults: -
 Yarn tension too high
 Lycra guide roller block or
jam
 Needle not properly work
Remedies: -
 Maintain proper yarn
tension
 Ensure smooth running of
guide roller
 Change defective needle

13. Yarn contamination
Causes of faults: -
 Presence of dead fibers
and other foreign materials
 Presence of the foreign
materials, in the stable fiber
mixing
Remedies: -
 Use rich fiber mixing for the
yarns
 Segregate the knitting m/c
with mosquito nets to
prevent the fibers flying
from neighboring

14. Miss yarn
Causes of faults: -
 Yarn break
 Positive feeder jam
 Excessive needle tension
 Weak yarn
Remedies: -
 Yarn strength must be
sufficient
 Smooth running of feeder
 Proper needle tension

15. Tara fault (Star)
Causes of faults: -
 For high r.p.m of m/c
cylinder
 One part dyeing
Remedies: -
 Maintain proper r.p.m of
m/c cylinder
 Range should be upto 23

16. Dyeing faults

17. Uneven dyeing
Causes of faults: -
 Inadequate scouring of the grey
fabric
 Correct pH value not maintained
 Water hardness
 Improper neutralization
 Improper migration
Remedies: -
 Scour the grey fabric
thoroughly, to remove all the
impurities from the fabric
 Maintain the correct pH value
 Maintain water hardness
 Proper neutralization
 Proper migration

18. Uneven dyeing
Causes of faults: -
 Improper neutralization
 Improper dyes dosing
 Improper soda dosing
 Improper migration
 Improper leveling agents
Remedies: -
 Proper neutralization
 Proper dyes dosing
 Proper soda dosing
 Proper migration
 Proper leveling agents

19. Uneven dyeing
Causes of faults: -
 Dyeing m/c stoppage, due to
power failure or the fabric
entanglement in the dyeing
m/c
 Correct pH value not
maintained
 Improper leveling agent
 Water hardness
Remedies: -
 Use a power back up for the
dyeing operation to be
completed uninterrupted
 Maintain correct pH value
 Use appropriate leveling
agents
 Maintain water hardness

20. Dye spots
Causes of faults: -
 Colored spots due to dye
deposits on the m/c
Remedies: -
 Pay attention to cleanness
in the m/c

21. Pilling
Causes of faults: -
 Due to friction of fabric
 Poor yarn quality
Remedies: -
 Need good enzyme
treatment
 By using combed yarn

22. Uneven dyeing
Causes of faults: -
 Improper migration
 Improper neutralization
 Inadequate scouring of the
grey fabric
Remedies: -
 Scouring the grey fabric
thoroughly
 Proper migration
 Proper neutralization

23. Soda spot
Causes of faults: -
 Improper dosing of soda
Remedies: -
 Proper dosing of soda

24. Finishing fault of knit
dyeing fabric

25. Uneven
Causes of faults: -
 Unstable dye dispersion
 Dispersing agent not
enough
 Wrong temperature
Remedies: -
 Select dyes with better
dispersion stability
 Proper temperature
maintained

26. Skew
Causes of faults: -
 Over width for this fabric
Remedies: -
 By using weft straightening
device
 Maintain proper width

27. Slitting fault
Causes of faults: -
 It is causes due to operator
carelessness
Remedies: -
 Operators have to slit fabric
through slitting mark

28. Uneven brushing
Causes of faults: -
 Not proper soft
 Roller pins problem
Remedies: -
 Use softener
 Check pins

29. Crease mark
Causes of faults: -
 Improper motion of padder
 Improper fabric movement
Remedies: -
 Proper motion of padder
 Ensure smooth running of
fabric
 Use anti-creasing agents

30. Unwanted mark
Causes of faults: -
 Due to contact with oil or
grease covered exposed
m/c parts
 Careless handling could be
another cause
Remedies: -
 Use of strong oil which can
be removed
 Proper handling should be
taken

31. Oil mark
Causes of faults: -
 Due to contact with oil or
grease covered exposed
m/c parts
 Careless handling could be
another cause
Remedies: -
 Use of strong oil which can
be removed
 After every process, if
possible check filter and
clean it

32. Silicon spot
Causes of faults: -
 Long time deposit of
solution
 Improper mixing of the
silicon
Remedies: -
 Proper mixing of the silicon
 Use the right silicon
 Maintain the correct pH
value, before application

33. Silicon mark & Burn effect
Causes of faults: -
 Long time deposit of
solution
 Improper mixing
 For over or high
temperature this burn effect
is visible
 Twice stenter
Remedies: -
 Proper mixing
 Select suitable silicon
 Maintain correct
temperature

34. Line mark
Causes of faults: -
 This mark are caused due
to the excessive pressure
of the roller
Remedies: -
 Pressure of roller should be
maintained
 Take care of fabric

35. Burning effect
Causes of faults: -
 For wrong temperature
 Unawareness of operator
Remedies: -
 Maintained proper
temperature
 By using experienced
manpower

36. Chemical spot
Causes of faults: -
 Improper mixing of
chemical
 Weak chemical
 Unawareness of operator
Remedies: -
 Proper mixing of chemical
 Use appropriate chemical
 By using experienced
manpower

37. Uneven brushing
Causes of faults: -
 Too much pressure of the
cylinder roller is the causes
Remedies: -
 Operator should take care
when fabric is running
 Uniform motion
 R.P.M should maintained

38. Uneven brushing
Causes of faults: -
 Too much pressure of the
cylinder roller is the causes
Remedies: -
 Operator should take care
when fabric is running
 Uniform motion
 R.P.M should maintained

39. Sewding fault
Causes of faults: -
 Wrong m/c set up
 Over speed /r.p.m
 Displace of pin
Remedies: -
 Installed proper m/c set up
 Maintain correct cylinder
speed
 Check and proper
placement of pin

40. Unwanted mark
Causes of faults: -
 Due to contact with iron
rust from m/c parts
 If fabric wet long time
 Unclean roller or padder
Remedies: -
 Try to clean m/c parts
 Keep fabric dry
 Clean roller and padder