Testing yarns is essentials. The basic tests that are essential are explained in this video. The yarn number systems the different tests for yarn like strength, length, elongation are discussed here.

1. TEST FOR
YARN
DR. S. AISHWARIYA
INSPIRE(DST) &ASSISTANTPROFESSOR,
DEPARTMENTOFTEXTILES ANDCLOTHING
AVINASHILINGAMUNIVERSITY FORWOMEN,
COIMBATORE.
Date

2. Contents in this presentation
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

3. Evaluation of Yarn
Yarn Numbering
[Direct system, Indirect and Metric system]

4. It is used to denote relationship
between length and weight of
the yarn
1 tex = 1 gm/km
50/1 = 50 singleyarns840 yards= 1lbs=1sWeight (in grams) of
9,000 metresof filament
Weight in gramsof
onekilometreof yarn
Mass/ length Length/ mass

5. Yarn NumberingYarn Numbering
• Yarn is measured using
yarn number/count /size
• Yarn numbering describes the
relationshipof lengthandweight
• Since various parts of world has
different system – universal
referencewasinvented

6. Direct Numbering
1. Deniersystem (9000 mts - ? weight)
 Used to measuresizeof silk and man-made filaments and yarns
 Denier isweight (in grams) of 9,000 metres of filament (length)
Eg:
 9,000 metresof ayarn weigh 15 grams, it isa15-denier yarn
 9,000 metresof ayarn weigh 100 grams, it isa100-denier yarn and much
coarserthan the 15 - denieryarn
(more length – more weight)
Thus, a smaller number indicatesafiner yarnsmaller number indicatesafiner yarn
 15 denier isfineyarn and 100 denier iscoarseyarn
 Limitation: This cannot be used to measure staple yarns
(Eg. Bamboo/Bananafiber)

7. Direct numbering
2. TEX system (1 km yarn -?weight)
 Found in 1873
 Used for stapleand filament yarn
 Measured using
Weight in grams of one kilometre (1000mts. /3,300 feet) of yarn

8. Indirect systems [based on lengthperunitweight]
• 1 pound isfixed asstandard unit (weight) – yarn’slength will bemeasured until
it reach 1 pound
• Sizenumber indicateslength of yarn needed to reach aweight of onepound.
Staplefibresweight - for specific length of yarn
• This means, very fine yarn, will have to be much longer (to attain that weight)
than acoarseyarn to weigh thesamepound.
• Higherthe number(count) – finerthe yarn
• In US, number of hanksper pound
Fine - 840 yards forcotton and spun silk = 1 pound (Metric method)
560 yards forworsted yarns = 1 pound
300 yards (a lea) forlinen = 1 pound
256 yards forwoollen yarns = 1 pound
Each of above fibre, differin length to reach that 1 pound target

9. 1 lb = 0.4541 kgs

10. Contents
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

11. To know Yarn numberdifferent
instruments are used
1.Beesley Balance
2.Wrap Reel Balance
3.Quadrant Balance
4.Stubb Yarn Balance

12. To assessyarn weight
Physical balanceand
Quadrant balance(+
Wrap reel)

13. 1. Physical balance
Using theweight on
onesidethesample
placed on other sideis
weight hencecan be
calculated

14. 2. Quadrant
Balance (GSM)

15. a. Wrap reel
• Using wrap reel skeins of yarn
can be prepared
• The yarns of required length can be
prepared
• It has 1 meter, 1 yard/ 54
inch circumference collapsible
reel
• An electronic counter helps in
making the number of rotations
count.

16. b. Quadrant balance
Using Wrap reel aspecific length of yarn istaken
A given length of yarn isplaced and theweight can beseen on thebalance
Unlike the beam balance which uses the standard weight, quadrant
balance can weigh the samples weight directly on the scale.
Even small count - 0.001 grams can bemeasured
Latest - digital quadrant balance
Significance:
Count can be directly found by the reading that is displayed on the scale
We have weight from Q. balance and length from wrap reel. Yarn count can
be calculated

17. Scale Sample length
0.1 to 1.0 4 yard sampleof sliver
0.1 to 0.6 20 yard roving sample
4sto 80s 840 yardsof yarn
Using the quadrant balance
Morethan onetypeof scaleisseen
Paper, cardboard, fleece, rubber, leather and
felt aremeasured using quadrant balance Quadrant balance
Formulae:
Yarn count (N) =(Wx I)
L
W- Weight of the sample
L- Length of sample
I– Unit of length of the sample

18. Contents
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

19. Yarn twist - Importance
Twist estimation
1. Single yarn
2. Twist &untwist method

20. • Yarn strength
• Colour accuracy after dyeing
• Degreeof cheese yarn
• Rateof rewinding – preparation of weaving
• Fabric Shrinkage (moretwist – moreshrinkage– in summer)
TWISTAFFECTS
Yarn twist isdefined asthespiral arrangement of fibres
Yarn name Low yarn twist Medium yarn twist Strong yarn twist SuperStrong yarn
twist
Yarn twist
(No. of twist/ meter)
Under 300 300 - 1000 1000 - 3000 Above3000
YARN TWIST- IMPORTANCE

21. Test for Twist
• Thesample of yarn istaken in normalcondition
• Careistaken not to touch the area where twist is measured, but
on theendsof theyarn
Test 1:
Straightened fibretechnique/ DirectCountMethod(yarn is taken and holding
one point untwisting is done)
Test 2 :
Twist contraction technique/ Untwist And Re-twist metho d (yarn is taken and
holding one point untwisting and then re-twisting is done – difference
length is noted)

22. • Thesampleyarn istaken and kept in between thejaw and untwisted until all thetwist is
removed.
• Using thecounter, numberof turns used to untwist theyarn can begot.
• Thisdivided by length of the yarn for test givesthevalue– twist perunit length
STRAIGHTENEDFIBRETECHNIQUE/
DIRECTCOUNTMETHOD

23. 2. Twist measurement - untwist and twist method
• It is fact that when yarn is twisted,
length decreased.
• Similarly, when untwisting a twisted
yarn, length increase
• The difference can be used to understand
thetwist.
Method: untwist the known length of yarn –
and visually check if twist isremoved
• Done: Manually/automatic
• Morereliable

24. The method is based on the assumption that
amount of twist put in
is equal to
the twist that has been removed
1.Thisisdoneby placing the yarn on clamp with pointer
2.Theweight isused at theend of theyarn
3.Astwist isremoved, yarn extends, pointerreaches vertical position
4.Now jaw iskept rotating, so
twist isadded and pointeris
back to zero again

25. Contents
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

26. Yarn diameter
(Video shown on finding diameter)
• The fiber/ and the volume it can
create insideayarn isimportant
• Using a microscope (optical method)
the yarn diameter can be obtained - but
will not be uniform.
Yarn diameteraffects
• fabric properties like width, cover
factor, porosity and comfort
properties
• Compressibility and other mechanical
property of fabric

27. Yarn diameter
It isdifferent for each fibretype
•Wool hasnearly round cross-section
•Silk hasatriangularcross-section
•Cotton islikeflattened tube
•Man-madefibresareoften madewith trilobal (nylon), staror
hollow cross-section for particular purposes
Measuring isnot easy asflattening of yarn is done by
applying pressure, which createsan unstable/ unreliableresult
Also twist cannot be uniform throughout the yarn.
•Thick yarn– medium twist
•and thin yarn – finetwist
Test : Doneby using
microscope– software–
ruler – excel sheet. (As
video)

28. Contents
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

29. Yarn strength –
Singleyarn strength (leastrength)
• Strength is important during yarn
processing and end products
life
• Testing is done by finding of
load - elongation curve or
stress - strain curve and
breaking point orstress

30. Lea strength tester
Testing strength of cotton yarn
Definition:
Strength is the force required to break a material and is
measured pounds
•We assume that sample is extensible and no external force is
acting
Things needed:
•Cotton yarn (1 lea), wrap reel, lea strength tester and electrical
balanceareneeded
•1 lea= 120 yards

31. Procedure
1.One lea cotton yarn is measured using
wrap reel
2.20 samples like that are taken for
testing
3.Sample is taken and fixed between
upperand lowerjaw
4.Machine is turned on, and readings are
seen, till yarn is torn/broken. After
break – readings are noted
5.It is repeated for all 20 and finally
averageistaken.

32. Contents
1. Evaluation of yarns Direct system, indirect and metric system
2. Quadrant balance
3. Physical balance
4. Twist
5. Yarn diameter
6. Yarn strength singleyarn strength, leastrength
7. Yarn evenness
• Importance
• Twist estimation
• Singleyarn
• Twist & untwist method

33. 33
Yarn evenness–
Importanceand test
• Surface irregularity of ayarn is
important for processing
and also theappearanceof thefabric.
• It istested by analysing the lengthwise
of the variation in diameter of theyarn
• Visual evaluation and electronic
methods areused for thispurpose.

34. References
1. https://nptel.ac.in/courses/116102029/
2.https://textilelearner.blogspot.com/2013/07/different-types-of-fabric-testing-
with.html
3. Principlesof TextileTesting: An Introduction to Physical Methodsof Testing
TextileFibres, Yarnsand Fabrics, J. E. Booth, 1986
4. Handbook of TextileTesting and Quality Control. Elliot B. Grover and D. S.
Hamby. TextileBook Publishers(Interscience), New York, 1960
5. A Practical Guideto TextileTesting, K. Amutha, Woodhead Publishing
Company, India, 2016.