ISO
2062
INTERNATIONAL
STANDARD
Second edition
1993-10-01
Corrected
and reprinted
1995-03-1 5
TextilesVarns from packages Determination of single-end breaking force
and elongation at break
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Textiles Fils sur enroulements
Détermination de la force de rupture
et I'allongement à la rupture du fi! individuel
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Reference number
ISO 2062:1993(E)
INTERNATIONAL
Textiles
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5TANDARD
ISO 2062:1993(E)
Varns from packages -
Determination of
single-end breaking force and elongation at break
1 Scope
NOTE 2
A method for the testing of glass yarns is given
in ISO 3341 :1984,
Textile glass -
Yarns- Determfnation
of breaking force and breaking elongation.
1.1 This International Standard specifies methods
for the determination of the breaking force and elongation at break of textile yarns taken from packages.
Four methods are given:
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A: manual; specimens are taken directly from
conditioned packages;
B: automatic; specimens are taken directly from
conditioned packages;
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C: manual; relaxed test skeins are used after cc.Jf)ditioning;
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D: manual; specimens are used a(ter wetting.
1.2 Method C should be used in cases of dispute
regarding elongation at break of the yam.
NOTE1 Methods A. 8 and C are expected to give the
same results for yarn strength but method C may give
somewhat truer (and higher) values of elongation than A or
B. Method D is likely to give results differing, for both
breaking force and elongation at break, from t:-Jose obtained
by method A. 8 or C.
,
1.3 This International Standard specifies methods
using constant rate of specimen extension (CRE)
tensile testers. Testing on the now obsolete constant
rate of travei (CRT)and constant rate of loading (CRl)
instruments is covered, for information, in annex A,
in recognition of the fact that these instruments are
still popular and may be used by agreement.
1.4 Tl1is International Standard applies to ali types
of yarn except glass yarns, elastomeric yarns, aramid
yarns, ceramic yarns, carbon yarns and polyolefin tape
yarns.
1.5 This International Standard is applicable to yarns
from packages but can be applied to yarns extracted
from fabrics, subject to agreement between the interested parties.
1.6 It is intended for the single-end (single-strand)
testing of yarns.
NOTE3
The skein method of testing is given in
Textiles - Yarns from packages - Method
of test for breaking strength of yarn by the skein method.
ISO 6939:1988,
2
Normative references
The following standards contain provisioris which,
through reference in this text, constitute provisions
of this International Standard. At the time of publication, the editions indicated were valid. Ali standards
are subject to revision, and parties to agreements
based on this International Standard are encouraged
to investigate the possibility of applying the most recent editions of the standards indicated below.
Members of IEC and ISO maintain registers of currently valid International Standards.
ISO 139:1973,
Texti/es - Standard atmospheres
for
conditioning and testing.
ISO 2060:-1), Textiles - Yarn frem packages - Determination of linear density (mass per unit /ength) by
the skein method.
3
Definitions
For the purposes of this International Standard, the
following definitions apply.
1) To be published. (Revision of ISO 2060:1972)
1
ISO 2062:1993(E)
3.1 breaking force (load):Maximumforce applied
to a specimen in a tensile test carriedto rupture. For
yarns. it is preferablyexpressed in centinewtons.
3.2 elongation at break: Increase in length of a
specimen produced by the breaking force. It is expressed as a percentage of the original nominal
length.
3.3 breaking tenacity: Ratio of a yarn's breaking
force to its lineardensity. It is usually expressedin
centinewtonsper tex.
3.4 constant rate of specimen extension (CRE)
tester: Testing machine in which one end of the
specimen is held in a virtually stationary clamp and the
other end is gripped in a clamp that is driven at a
constant speed. A suitable system is provided for detecting and recording the force applied and the elongation.
3.5 clamp: That part of a tensile testing machine
used to grip the specimen by means of suitable jaws.
3.6 jaws: Those elements of a clamp which grip the
specimen.
3.7 gauge length: Length of the specimen measured between the points of attachment to clamps
while under tension. In bollard or capstan clamps. it
is the distance between their gripping points. measured along the path of the yam.
3.8 package: Length of yarn in a form suitable for
b) The constant rate of displacement of the moving
clamp shall be 500 mm/min or 250 mm/min, to an
accuracy of :I: 2 %, with higher rates being permitted for automatic testers on agreement.
c) The maximum error of the indicated force shall not
exceed 2 % of the true force.
d) The teste r may be of the manual or automatic
type.
e) The clamps for gripping the specimens shall prevent slipping or cutting of the specimens and
breaks at the jaws. Flat-faced unlined jaws shall
be the normal type but. if these cannot prevent
slippage, then other types of clamp may be used
on agreement, such as lined jaws. bollard clamps
or other types of snubbing device. As the type of
clamp may influence the reading of the elongation.
ali parties shall use the same type.
f) The tester shall be equipped with an autographic
force/elongation recording device of sufficiently
fast response. or with a system directly recording
the breaking force and elongation at break.
g) The teste r shall be capable of setting a pretension
either by means of a set of pretensioning weights
or by the use of the force-measuring device.
5.2 Reei. for preparing test skeins from the laboratory sample (for methods C and D).
ported (e.g. cones. bobbins) or unsupported (e.g.
skeins. balls).
5.3 Swift. or similar device, for holding the test
skein under zero tension and permitting easy transfer
of the yarn to the tensile tester (for method C).
4 Principie
5.4 Receptacles, for immersing the sample or the
specimens in water (for method D).
use. handling. storing, etc. Packagesr can be sup-
A specimen of yarn is extended until rupture by a
suitable mechanical device, and the breaking force
and elongation at break are recorded. A constant rate
of specimen extension of 100 % per minute (based
on the ini~ial specimen length) is used. but higher
rates are permitted for automatic testers on agreement. Two gauge lengths are permitted: usually
500 mm
(with a rate of displacement of
500 mm/min), and exceptionally 250 mm (with a rate
of displacement of 250 mm/min).
5
Apparatus and materiais
5.1 Constant rate of specimen extension ICRE)
tester. which complies with the following require-
5.5 Tap water. at room temperature (for method
D).
5.6 Nonionic surfactant,
(for method D).
6
6.1
0.1 % aqueous solution
Sampling
Samples shall be taken in accordance with
a) the directions given in the material specification
when available. or
ments.
b) the procedures described in 6.2 to 6.7.
a) The tester shall be capable of being set at gauge
lengths of 500 mm :t 2 mm or 250 mm :t 1 mm,
or preferably both.
6.2 A bulk sample shall be taken of one or more
cases, as representative of the lot to be tested as
follows:
2
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ISO 2062:1993(E)
No. of cases
No. of cases selected
at random
3 or less
4 to 1O
11 to 30
31 to 75
76 or more
1
2
3
4
5
6.3 If only mean values are required, then 10 packages shall be taken from the bulk sample, distributed
as evenly as possible among the cases and among
the levels in each case.
6.4 Except for the provisions of 6.5, the minimum
number of specimens to be tested shall be 50 for
single spun yarns and 20 for other yarns. The specimens shall be distributed as evenly as possible among
the 10 packages.
6.5
If the variability of the tests is known and only
mean values are required, then the number of specimens shall be calculated as 0,17v2, where v is the
coefficient of variation of the individual breaks (expressed as a percentage) obtained from experience
on similar material.
NOTES
4 This numberof specimenswill give a precision(1,96 x
the standard error of the mean) of :f: 4 % at a probability
levei of 90 %.
5 Strength testing is a "one-tail" test; that is, "yam shall
not be weaker than ..." but "may be stronger than ..."
When specifying 90 % probability, one tair of the distribution
is 5 %, or exactly the same as the two tails together of the
more common 95 % probability appropriate for a "two-tail"
test.
6.6 If the coefficient of variation is to be determined
in addition to the mean, then 20 packages shall be
taken from the bulk sample and at least 200 specimens shall be tested for single spun yarns and at least
100 specimens for ali other types of yarn.
6.7 If ~pecimens are to be extracted from fabrics
[not suitable for automatic testers (method B)], then
the fabric sample shall be large enough to furnish a
sufficient number and length of specimens. The test
specimens shall be taken so that the twist in the yarn
is not changed during sampling. In woven fabrics,
warp specimens shall be taken from different ends
and weft specimens shall be taken at random frem
several sections of the sample to be as representative
of the yarn as possible. In knitted fabrics, specimens
shall refJresentas many different yarns as possible.
7
Preconditioning and conditioning
7.1 The atmospheres for preconditioning, conditioning and testing shall be as specified in ISO 139.
7.2
For methods A to C, the sample packages or
test skeinsshall be preconditionedfor a minimumof
4 h.
NOTE 6
Preconditioning can often be dispensed with if
the samples are conditioned directly "from the dry side".
7.3
After preconditioning, the sample shall be
brought to moisture equilibrium under the conditioning atmosphere. For skeins, overnight conditioning is
usually sufficient, but for tightly wound packages a
minimum of 48 h is necessary.
7.4 Preconditioning and conditioning are not required for wet tests (method D).
8
Procedure
8.1 General
8.1.1 If more than one condition of testing is permitted, usually by agreement, then ali parties interested in the test results shall perform the test under
the same conditions (Le. gauge length, rate of displacement, type of clamp, temperature, pretension).
8.1.2 Two gauge lengths are permitted: the usual
length of 500 mm, and a length of 250 mm which can
be used only if
a) the extension of the instrument is insufficient to
accommodate a 500 mm specimen, or
b) by agreement between the parties.
8.1.3 If calculation of the breaking tenacity is required, determine the linear density of the yarn in accordance with ISO 2060.
8.1.4 Use a rate of displacement of 500 mm/min at
the gauge length of 500 mm, and 250 mm/min at the
gauge length of 250 mm. In addition, for automatic
testers only (method B), higher rates are permitted
by agreement; 400 %/min or 1 000 %/min are recommended.
8.1.5 Unwind the yarn from the package as is done
in normal use.
8.1.6 Before clamping the specimen, check that the
jaw5 are correctly aligned and parallel, 50 that the
force applied produces no angular deviation.
8.1.7 Insert the specimen in the clamps with a pretension of 0,5 cN/tex :i: 0,1 cN/tex for conditioned
specimens, or 0,25 cN/tex :i: 0,05 cN/tex for wet
specimens. For textured yarns, use a pretension
which will remove the crimp but not stretch the yam.
3
ISO 2062:1993(E)
NOTE7
For textured yarns, the following pretensions are
recommended {unless otherwise agreedl. calculated on the
nominal linear density of the yarn:
2,0 cN/tex :t 0,2 cN/tex, for polyester and polyamide
yarns;
1,0 cN/tex :t 0,1 cN/tex, for acetate, triacetate and
viscose yarns;
0,5 cN/tex :t 0,05 cN/tex, for for bi-shrinkage and jetbulked yarns, except for carpet yarns heavier than
50 tex.
8.1.8
Finally, seeure the specimen in the clamps.
8.1.9 Perform the test under the standard atmosphere for testing, as specified in 7.1.
8.4 Method C, manual, conditioned
specimens
8.4.1 Using the reei (5.2). take one test skein from
each package of the sample. The test skeins shall be
of sufficient length to give the required number and
length of test specimens.
8.4.2 Using the swift (5.3). allow the test skeins to
relax under minimal tension in the preconditioning and
eonditioning atmospheres (see 7.1).
8.4.3 Follow the procedures given in 8.1.1 to
8.1.11. When taking a specimen from the test skein
for insertion between the clamps, make sure its
length is at least 100 mm greater than the selected
gauge length; an exeess of 500 mm is recommended.
Be careful not to change the twist.
NOTE 10
With suitable modifications {see 6.71. this
methodmayalsobe usedfor yarnsfrom fabrics.
8.1.10 During the test, eheek that the specimen
does not slip between the jaws by more than 2 mm.
If it does so repeatedly, ehange the elamps or jaw
lining. Diseard tha results of the tests where slippage
oeeurs. Also diseard results of jaw breaks where
breaks oeeur 5 mm to the jaws or eloser.
8.1.11 Reeord the breaking force and elongation at
break (done automatieally in method B). For faney
yarns, reeord values for the first eomponent that
breaks.
NOTES
8 The values recorded for fancy yarns may be lower than
those defined in 3.1 and 3.2.
9 With bollard or capstan clamps, measurement of the
elongation is not accurate and is discouraged.
8.2 Method A, manual
8.5
Method D, manual, wet specimens
8.5.1 Take test skeins as deseribed in 8.4.1.
8.5.2 Before removing the test skein frem the reei,
wrap two or three turns of a strong thread (e.g. sewing thread) tightly around the skein at two places
about 2 em apart and securely tie the ends of the
thread. Cut the skein midway between the two
places. Fill a receptacle (5.4) with water (5.5). Lay the
eut skein flat on the surface of the water and leave it
until it sinks below the $urface under its own weight.
8.5.3 If the skein will not sink in the water, then hold
the yarn under the surface, e.g. by means of weights
attached to the ends, until the yarn is thoroughly
saturated (e.g. for 30 min). When the yarns are
r.ormally resistant to wetting, use a nonionic wetting
agent (5.6). Rinse out the wetting agent thoroughly
with water before testing the yam.
Take specimens directly frem the conditioned packages.
I
8.5.4 Remove the specimens individually frem the
water and test them within 60 s thereafter, following
the procedures given in 8.1.1 to 8.1.11.
Follow the proeedures given in 8.1.1 to 8.1.11. Insert
the test specimens manually into the elamps to perform the tensile test.
9 Test report
9.1 General information
8.3
Method B, automatic
The test report shall include the following information:
Take specimens directly from the conditioned paekages.
a) a reference
(ISO 2062);
Follow the procedures given in 8.1.1 to 8.1.6 and
8.1.9 to 8.1.11. Set the instrument to take specimens
frem the 10 or 20 packages of the sample (see 6.3
and 6.6). The test will be performed automatically.
b) lot number or other identification of the sample;
4
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to
this
International
Standard
c) type of package (cone, bobbin, ete.), its condition
idyed, bleached, etc.), and the manner in which
V
ISO 2062:1993(E)
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the yarn was withdrawn from the package (overend or from the side);
9.2
T est results
The following test results shall be given:
d) conditioning atmosphere and testing atmosphere
used;
e) sampling scheme used, the number of specimens
tested, and number of specimens discarded;
a) mean breaking force, in centinewtons (to three
significant figures);
b) mean elongation at break, as a percentage (to two
significant figures);
f) make of tester used;
g) test method used (A to D);
c) coefficient of variation of the breaking force, if required (to the nearest 0,1 %);
h) gauge length, rate of displacement and pretension
used;
d) coefficient of variation of percent elongation at
break, if required (to the nearest 0,1 %);
i) type of clamp and jaws used;
e) linear density of the yam, if determined, in tex (to
three significant figures);
j) date of the test.
f) breaking tenacity, if required, in centinewtons per
tex (to the nearest 0,1 cN/tex).
5