ASTM D1907/D1907M-12(2018)

Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method

SIGNIFICANCE AND USE
5.1 Test Method D1907/D1907M is considered satisfactory for acceptance testing of commercial shipments, since it has been used extensively in the trade for that purpose.  
5.1.1 In case of dispute arising from differences in reported test results when using Test Method D1907/D1907M for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories.  
5.1.2 Competent statistical assistance is recommended for the determination of such a bias. As a minimum, the two parties should take a group of test specimens that are as homogeneous as possible, and that are from the same lot of the material in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using statistical analysis for unpaired data, and an acceptable probability level chosen by the parties before testing begins. If a bias is found, either its cause must be identified and corrected, or the purchaser and supplier must agree to interpret future test results for that material with consideration to the known bias.  
5.2 This test method is intended primarily for the determination of the average linear density of yarns. However, the variations identified by the results may also provide useful information. If the coefficient of variation is to be calculated, each skein must be weighed separately, and a larger number of skeins will need to be tested (as compared to the number of skeins to be tested for the determination of the average yarn linear density alone).  
5.3 This test method includes seven options, depending on whether the yarn is scoured before weighing, weighed in the conditioned or oven-dried state, or whether or not the results obtained are adjusted for commercial moisture regain, or a commercial allowance. Option 1 (unscoured, conditioned yarn) is generally used f...
SCOPE
1.1 This test method covers the determination of the linear density of all types of yarn in package form, subject to the limitations of size and stretch given in 1.2 and 1.3. Provision is made for expressing yarn linear density in all the traditional yarn numbering systems.  
1.2 This test method is applicable to yarns that stretch less than 5 % when tension on the yarn is increased from 0.25 to 0.75 cN/tex [0.25 to 0.75 gf/tex]. By mutual agreement, and use of a lower than specified reeling tension, this method may also be adapted to measure the linear density of yarns that stretch more than 5 %, under the above force.  
1.3 This method is applicable to yarns finer than 2000 tex. However, it may be also adapted to coarser yarns by the use of skeins of shorter than specified lengths, and alternate reeling conditions, agreeable to the interested parties.  
1.4 Depending on the procedure used to calculate the moisture content of the yarn being tested, and its actual moisture content, or finish content, or both, one or more of the following options may be utilized.  
1.4.1 Unscoured Yarn: Option 1—Yarn at equilibrium with the standard atmosphere for testing textiles.
Option 2—Oven-dried yarn.
Option 3—Oven-dried yarn, plus commercial moisture regain.  
1.4.2 Scoured Yarn: Option 4—Scoured yarn at equilibrium with the standard atmosphere for testing textiles.
Option 5—Oven-dried, scoured yarn.
Option 6—Oven-dried, scoured yarn, plus commercial moisture regain.
Option 7—Oven-dried, scoured yarn, plus commercial allowance (commercial moisture regain, plus an allowance for finish).  
1.5 Specimens used to determine yarn linear density may also be used to determine the skein breaking strength of the yarn. Hence, this method provides the sequence of steps to be followed, to determine both these yarn properties.  
Note 1: The linear density of yarns produced with jute, or glass, may also be determined by the follo...

General Information

• Status: Published
• Publication Date: 30-Jun-2018
• ICS: 59.080.20 - Yarns
• Technical Committee: D13 - Textiles
• Drafting Committee: D13.58 - Yarns and Fibers

Relations

• Replaces: ASTM D1907/D1907M-12 - Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method
• Effective Date: 01-Jul-2018
• Refers: ASTM D2494-13(2020) - Standard Test Method for Commercial Mass of a Shipment of Yarn or Manufactured Staple Fiber or Tow
• Effective Date: 01-Feb-2020
• Refers: ASTM D4849-13(2018) - Standard Terminology Related to Yarns and Fibers
• Effective Date: 01-Jul-2018
• Refers: ASTM D123-17 - Standard Terminology Relating to Textiles
• Effective Date: 01-Mar-2017
• Refers: ASTM D123-15b - Standard Terminology Relating to Textiles
• Effective Date: 15-Sep-2015
• Refers: ASTM D123-15a - Standard Terminology Relating to Textiles
• Effective Date: 01-Sep-2015
• Refers: ASTM D123-15 - Standard Terminology Relating to Textiles
• Effective Date: 01-Apr-2015
• Refers: ASTM D4849-13e1 - Standard Terminology Related to Yarns and Fibers
• Effective Date: 01-Oct-2013
• Refers: ASTM D4849-13 - Standard Terminology Related to Yarns and Fibers
• Effective Date: 01-Oct-2013
• Refers: ASTM D4849-13e2 - Standard Terminology Related to Yarns and Fibers
• Effective Date: 01-Oct-2013
• Refers: ASTM D4849-13e3 - Standard Terminology Related to Yarns and Fibers
• Effective Date: 01-Oct-2013
• Refers: ASTM D2494-13 - Standard Test Method for Commercial Mass of a Shipment of Yarn or Manufactured Staple Fiber or Tow
• Effective Date: 01-Jul-2013
• Refers: ASTM D123-13a - Standard Terminology Relating to Textiles
• Effective Date: 15-Jun-2013
• Refers: ASTM D123-13ae1 - Standard Terminology Relating to Textiles
• Effective Date: 15-Jun-2013
• Refers: ASTM D123-13 - Standard Terminology Relating to Textiles
• Effective Date: 15-May-2013

Overview

ASTM D1907/D1907M-12(2018), titled “Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method,” establishes a widely accepted procedure for determining the linear density of yarns in package form. This standard is used across the textile industry to assess yarn quality for commercial shipments. Linear density, often referred to as yarn count or yarn number, is a critical property that defines the mass per unit length of yarn, impacting both processing and end-product performance.

This test method accommodates a range of yarns, including those spun on cotton, worsted, woolen, and bast fiber systems, as well as filament yarns. The method provides options for testing both scoured and unscoured yarns, under various moisture conditions such as conditioned, oven-dried, or under commercial moisture regain.

Key Topics

• Scope of Application: The test covers nearly all yarn types in package form, up to 2000 tex, and can be adapted to coarser yarns using modified skein lengths and reeling conditions.
• Multiple Testing Options: Seven distinct procedures allow for testing unscoured or scoured yarns, both in conditioned and oven-dried states, with adjustments for commercial moisture regain or commercial allowance as required in industry practice.
• Sampling and Statistical Considerations: The standard provides directions for sample selection, laboratory comparisons, and statistical analysis to resolve test result discrepancies between suppliers and purchasers.
• Variability Measurement: Besides determining the average linear density, the procedure allows evaluation of mass variation through the coefficient of variation, which is especially valuable for quality control.
• Dual Utility: The same test specimens can be used for measuring skein breaking strength, streamlining laboratory testing processes.

Applications

ASTM D1907/D1907M is a fundamental tool for:

• Quality Control: Ensuring consistent yarn linear density is essential for textile manufacturers and buyers to meet product specifications and functional requirements.
• Acceptance Testing of Shipments: The method is recognized as satisfactory for commercial acceptance testing, making it a standard reference in supply agreements.
• Laboratory Comparisons: In cases of disputed results, the standardized procedure enables objective, statistically-valid resolution.
• Research and Development: Yarn producers and R&D labs use this method to benchmark new fiber blends, spinning techniques, or finishing operations.
• Regulatory Compliance: As an internationally recognized method, it supports due diligence for compliance with trade and industry guidelines.

Related Standards

For comprehensive evaluation of yarn properties and complementary test methods, consider the following related ASTM standards:

• ASTM D1059: Test Method for Yarn Number Based on Short-Length Specimens
• ASTM D1578: Test Method for Breaking Strength of Yarn in Skein Form
• ASTM D4849: Terminology Related to Yarns and Fibers
• ASTM D2258/D2258M: Practice for Sampling Yarn for Testing
• ASTM D1909: Standard Tables of Commercial Moisture Regains and Commercial Allowances for Textile Fibers
• ASTM D2494: Test Method for Commercial Mass of a Shipment of Yarn or Manufactured Staple Fiber or Tow

These standards complement ASTM D1907/D1907M, offering additional guidance on yarn measurement, moisture regain, sampling, and related testing procedures.

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Keywords: ASTM D1907, skein method, linear density, yarn number, yarn count, textile testing, acceptance testing, yarn sampling, quality control, yarn linear density test.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D1907/D1907M − 12 (Reapproved 2018)
Standard Test Method for
Linear Density of Yarn (Yarn Number) by the Skein Method
This standard is issued under the fixed designation D1907/D1907M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope yarn. Hence, this method provides the sequence of steps to be
followed, to determine both these yarn properties.
1.1 This test method covers the determination of the linear
density of all types of yarn in package form, subject to the
NOTE 1—The linear density of yarns produced with jute, or glass, may
also be determined by the following approved methods: Specifications
limitationsofsizeandstretchgivenin1.2and1.3.Provisionis
D541, D578/D578M, and D681. The linear density of short yarn
made for expressing yarn linear density in all the traditional
segments, raveled from fabrics, may be determined by Test Method
yarn numbering systems.
D1059.
1.2 This test method is applicable to yarns that stretch less
1.6 The values stated in either SI units or inch-pound units
than 5% when tension on the yarn is increased from 0.25 to
are to be regarded separately as standard. The values stated in
0.75 cN/tex [0.25 to 0.75 gf/tex]. By mutual agreement, and
each system may not be exact equivalents; therefore, each
use of a lower than specified reeling tension, this method may
system shall be used independently of the other. Combining
also be adapted to measure the linear density of yarns that
values from the two systems may result in non-conformance
stretch more than 5%, under the above force.
with the standard.
1.3 This method is applicable to yarns finer than 2000 tex.
1.7 This standard does not purport to address all of the
However, it may be also adapted to coarser yarns by the use of
safety concerns, if any, associated with its use. It is the
skeins of shorter than specified lengths, and alternate reeling
responsibility of the user of this standard to establish appro-
conditions, agreeable to the interested parties.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.4 Depending on the procedure used to calculate the
1.8 This international standard was developed in accor-
moisture content of the yarn being tested, and its actual
dance with internationally recognized principles on standard-
moisture content, or finish content, or both, one or more of the
ization established in the Decision on Principles for the
following options may be utilized.
Development of International Standards, Guides and Recom-
1.4.1 Unscoured Yarn: Option 1—Yarn at equilibrium with
mendations issued by the World Trade Organization Technical
the standard atmosphere for testing textiles.
Barriers to Trade (TBT) Committee.
Option 2—Oven-dried yarn.
Option 3—Oven-dried yarn, plus commercial moisture re-
2. Referenced Documents
gain.
1.4.2 Scoured Yarn: Option 4—Scoured yarn at equilibrium 2.1 ASTM Standards:
with the standard atmosphere for testing textiles.
D123Terminology Relating to Textiles
Option 5—Oven-dried, scoured yarn. D541Specification for Single Jute Yarn (Withdrawn 1996)
Option6—Oven-dried,scouredyarn,pluscommercialmois-
D578/D578MSpecification for Glass Fiber Strands
ture regain. D681Specification for Jute Rove and Plied Yarn for Elec-
Option 7—Oven-dried, scoured yarn, plus commercial al-
trical and Packing Purposes (Withdrawn 2000)
lowance (commercial moisture regain, plus an allowance for D1059Test Method for Yarn Number Based on Short-
finish). Length Specimens
D1578Test Method for Breaking Strength of Yarn in Skein
1.5 Specimens used to determine yarn linear density may
Form
also be used to determine the skein breaking strength of the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
ThistestmethodisunderthejurisdictionofASTMCommitteeD13onTextiles contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
and is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers. Standards volume information, refer to the standard’s Document Summary page on
CurrenteditionapprovedJuly1,2018.PublishedJuly2018.Originallyapproved the ASTM website.
in 1961T. Last previous edition approved in 2012 as D1907/D1907M–12. DOI: The last approved version of this historical standard is referenced on
10.1520/D1907_D1907M-12R18. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1907/D1907M − 12 (2018)
D1909Standard Tables of Commercial Moisture Regains conditioned or oven-dried state, or whether or not the results
and Commercial Allowances for Textile Fibers obtained are adjusted for commercial moisture regain, or a
D2257Test Method for Extractable Matter in Textiles commercialallowance.Option1(unscoured,conditionedyarn)
D2258/D2258MPractice for Sampling Yarn for Testing is generally used for yarns spun on the cotton system, while
D2494Test Method for Commercial Mass of a Shipment of Options 6 and 7 (scoured, oven dried yarn, plus commercial
Yarn or Manufactured Staple Fiber or Tow moisture regain, or allowance) are generally used for filament
D4849Terminology Related to Yarns and Fibers yarns, or yarns containing wool fibers. The specific options to
be used in any instance shall be agreed upon by the parties, or
3. Terminology
as prescribed in test methods or tolerances.
3.1 For all terminology relating to D13.58, Yarns and
5.4 In Options 2, 3, 5, 6, and 7, an oven-dried sample is
Fibers, refer to Terminology D4849.
obtained by exposing the yarn in an oven with a supply of air
3.1.1 The following terms are relevant to this standard:
at standard textile testing conditions, as described in 6.3.
commercial allowance, commercial moisture regain, direct
yarnnumberingsystem,indirectyarnnumberingsystem,linear
6. Apparatus and Reagents
density for fiber and yarn, skein, yarn number, yarn numbering
6.1 Reel:
system.
6.1.1 General—A hand reel or motor driven reel having a
3.2 For all other terminology, refer to Terminology D123.
perimeterof1.000mor1.500yd.withatoleranceof 60.25%
is recommended. By prior agreement, reels having a perimeter
4. Summary of Test Method
of between 1.0 and 2.5 m [1.5 and 3.0 yd] may be used. The
reel shall be fitted with a traversing mechanism that will avoid
4.1 Specified lengths of yarn are wound on reels as skeins,
bunchingsuccessivewrapsofyarn,andwithanindicatorofthe
and weighed. The linear density of the yarn is computed from
lengthwound.Awarningbellthatringsataspecifiedlength,is
the mass and length of the skein. In some options, the skein is
alsorecommended.And,itisadvisablethatonearmofthereel
scouredbeforeweighing,and,dependingontheoptionchosen,
be collapsible, to allow for easy removal of the wound skeins.
the mass of the skein may be determined after oven drying, or
6.1.2 ReelPerimeter—Determinetheactualperimeterofthe
after conditioning.
reel by winding a 0.6 cm. [0.25 in.] wide steel measuring tape
around the reel. Tension the tape prior to directly reading the
5. Significance and Use
circumference of the reel, by attaching a 0.5 kg [1.0 lb] weight
5.1 Test Method D1907/D1907M is considered satisfactory
to the end of the tape. Repeat this measurement near each end
for acceptance testing of commercial shipments, since it has
of the bars of the reel, and in the center. If the circumference
been used extensively in the trade for that purpose.
at any of these areas is outside the limits of 1.000 6 2.5 mm
5.1.1 In case of dispute arising from differences in reported
[1.500+0.1 in.], adjust the fly wheel to bring the measure-
test results when using Test Method D1907/D1907M for
ment(s) within the limits.
acceptancetestingofcommercialshipments,thepurchaserand
6.1.3 Yarn Tensioning—The reel shall be fitted with either a
the supplier should conduct comparative tests to determine if
positive feed system at a controlled tension of 0.5 cN/tex
there is a statistical bias between their laboratories.
[0.05gf⁄ tex] or with an adjustable tension device. The length
5.1.2 Competent statistical assistance is recommended for
oftheskeinsshouldbechecked,andvariationsinlengthnotbe
thedeterminationofsuchabias.Asaminimum,thetwoparties
allowed to exceed 60.25 % (see Annex A1).
should take a group of test specimens that are as homogeneous
6.2 Balance—For the determination of average yarn linear
as possible, and that are from the same lot of the material in
density, a balance of suitable capacity, graduated in grams or
question.Thetestspecimensshouldthenberandomlyassigned
grains, with a sensitivity of 1 part in 1000 should be used. If
in equal numbers to each laboratory for testing. The average
single skeins are weighed, a balance graduated directly in yarn
results from the two laboratories should be compared using
linear density may be used.
statistical analysis for unpaired data, and an acceptable prob-
ability level chosen by the parties before testing begins. If a
NOTE 2—The 1:1000 balance sensitivity is needed to ascertain the
bias is found, either its cause must be identified and corrected,
completion of conditioning, or oven drying. For subsequent weighings of
skeins, a 1:500 sensitivity has been found to be sufficient.
orthepurchaserandsuppliermustagreetointerpretfuturetest
NOTE 3—For the calculation of the variation of yarn linear density, a
results for that material with consideration to the known bias.
1:100 balance sensitivity is sufficient to weigh individual skeins, after the
5.2 This test method is intended primarily for the determi-
skeins are conditioned, or oven-dried.
nation of the average linear density of yarns. However, the
6.3 Drying Oven—Anoven,ventilatedandcapableofbeing
variations identified by the results may also provide useful
controlled in a temperature range of 105 6 3°C [221 6 5°F],
information. If the coefficient of variation is to be calculated,
is required to dry the skeins. The oven should be of sufficient
each skein must be weighed separately, and a larger number of
design to facilitate the free passage of air through the
skeins will need to be tested (as compared to the number of
specimens, and should be supplied with a current of air
skeins to be tested for the determination of the average yarn
sufficient to change the air in the oven once every 4 min. The
linear density alone).
specimens shall be protected from any direct heat, radiating
5.3 This test method includes seven options, depending on from the heating units of the oven. Air supplied to the oven
whether the yarn is scoured before weighing, weighed in the shall be at the standard atmosphere for testing textiles. The
D1907/D1907M − 12 (2018)
oven may be provided with facilities to shut off the air current Ifsuchdifferencesaresuspected,testmorethanoneskeinfrom
and weigh the specimens, without removing them from the each package, without reducing the number of packages
oven. sampled for testing, taking skeins at intervals throughout the
packages.
6.4 Facilities for Scouring (Options 4, 5, 6, and 7), as
indicated in Appendix X2, or in Sections 6.1 and 6.3 of Test
8. Conditioning
Method D2494.
8.1 Before reeling test skeins, condition yarn in skein form
6.5 Weighing Cans, with tight fitting lids, and of sufficient
in the standard atmosphere for testing textiles for a minimum
size to hold all skeins, or groups of skeins (Options 2, 3, 5, 6,
of 1 h, and yarn on packages for a minimum of 3 h.
and7),iftheweighingistobedoneoutsidetheoven.Weighing
Additionally, prior to testing, preconditioning of the test skeins
bottles with ground-glass stoppers may also be used.
may be required for Option 1, but is not necessary for Options
6.6 Auxiliary Facilities, suited to the specimens and options
2 through 7.
used, such as sample supports, tared wire gauze baskets of
NOTE 6—For Options 2 through 7, where the yarn is scoured or
corrosion resistant metal, dessicators of sufficient size to hold
oven-driedafterreeling,conditioningpriortoreelingisrequiredtoensure
the weighing cans or bottles, and an efficient dessicant.
a correct skein length.
7. Sampling
9. Procedure
7.1 LotSample—Asalotsampleforacceptancetesting,take
9.1 General:
at random the number of shipping units directed in an
9.1.1 The procedure used depends on the options selected;
applicable material specification, or other agreement between
Table 1 shows the steps to be followed for each option.
the purchaser and supplier, such as an agreement to use
9.1.2 If both the breaking load and linear density are to be
Practice D2258/D2258M. Consider cartons or other shipping
determined, test conditioned skeins for breaking strength
units to be the primary sampling units.
before scouring, as directed in Test Method D1578.
For Option 1, condition the yarn prior to reeling test skeins.
NOTE 4—An adequate specification or other agreement between the
Pre-condition, then condition the test skeins; perform skein
purchaser and the supplier requires taking into account the variability
between shipping units, between packages or ends within a shipping unit, breaking load tests prior to weighing the skeins. For all the
andbetweenspecimensfromasinglepackage,toprovideasamplingplan
other Options, condition the yarn prior to reeling test skeins.
with a meaningful producer’s risk, user’s risk, acceptable quality level,
Precondition, then condition the test skeins, break them, then
and limiting quality level.
proceed with oven drying or scouring, or both, and the
7.2 Laboratory Sample—As a laboratory sample for accep-
subsequent steps shown in Table 1.
tance testing, take at random from each shipping unit in the lot
sample the number of packages or ends directed in an
TABLE 1 General Procedures
applicable material specification, or as agreed to between
purchaser and supplier (such as an agreement to use Practice Referenced Sections
D2258/D2258M). Preferably, the same number of packages
Step 1
All Options:
should be taken from each shipping unit in the lot sample.
Selection of lot sample, and packages 7
7.2.1 Average of Yarn Linear Density—When only the
Conditioning prior to reeling 8.1
average of the yarn linear density is to be determined, take a
Setting of skein gage, and reeling of skeins 9.3 to 9.6
Step 2
laboratory sample as follows:
Option 1—Unscoured yarn in standard atmosphere for
Filament yarns — 5 packages
testing textiles:
Yarns spun on Worsted
Preconditioning and conditioning 9.7, and 9.8
or Cotton systems — 10 packages
Weighing of skeins, and calculation of yarn linear 9.10, 10.1, and 10.2
Yarns spun on Bast, or
density
Woollen systems — 20 packages
Option 2—Unscoured, moisture free yarn, and,
Option 3—Unscoured, moisture free yarn, with
7.2.2 Average and Variability of Yarn Linear Density—
commercial moisture regain:
When both the average and variability of the linear density of
Oven drying 9.9
Weighing of skeins, and calculation of yarn linear 9.10, and 10
yarn are to be determined, take a laboratory sample of 30
density
packages. If possible, take an equal number of randomly
Option 4—Scoured yarn, in standard atmosphere for
selected packages from each case in the lot sample.
testing textiles:
Scouring 9.6, and X2
7.3 Test Specimens—Test one skein from each package in
Preconditioning, and conditioning 9.7, and 9.8
the laboratory sample. Weighing of skeins, and calculation of yarn linear 9.10, 10.1, and 10.2
density
NOTE 5—Since the variation in yarn linear density is usually higher Option 5—Scoured, oven-dried yarn
between packages than within packages, no appreciable improvement in Option 6—Scoured, oven-dried yarn, with commercial
moisture regain:
precision can be expected by testing more than one skein from each
Option 7—Scoured, oven-dried yarn, with commercial
package.
allowance:
7.3.1 An exception to the information provided in Note 5 Scouring 9.6, and X2
Oven drying 9.9
mayoccurinpackagesoffilamentyarns;consistentdifferences
Weighing of skeins, and calculation of yarn linear 9.10, 10.1, and 10.2
in yarn linear density are sometimes present between yarn on
density
the outside of the package, as compared to yarn on the inside.
D1907/D1907M − 12 (2018)
9.2 Tension for Reeling: dures listed in Sections 7.8, 7.9, and 7.12 of Test Method
9.2.1 To establish the required tension for reeling, reel a D2494 may also be used.
skein from each of two packages, and immediately check their
9.6 Preconditioning (Options 1 and 4 only)—Precondition
lengths,asprescribedinAppendix.Ifthelengthofeitherskein
skeins of the as received yarn, reeled for Option 1, or scoured
departs from the set length by more than 0.25%, adjust the
and air-dried skeins for Option 4, for at least3hinan
reeling tension and repeat the reeling measurement until both
atmosphere that does not exceed a temperature of 50°C
skeinsfallwithinthe 60.25%tolerance.Ifyarnissuppliedon
[122°F], and with a relative humidity between 10 and 25%.
more than one type of package, check two skeins from each
9.6.1 Ifpreconditioningiscarriedoutinanoven,ensurethat
type of package as above. It may be necessary to use different
the yarn does not become too dry.
reeling tensions for each package type.
9.2.2 If,whenreeledundertheleastpossibletension,skeins NOTE8—InOption1,preconditioningandconditioningofyarnmaybe
done before reeling. However, it is usually not convenient to precondition
are more than 0.25% shorter than the nominal length, reel
large packages in an oven or a cabinet. Therefore, it may be preferable to
skeinslongerthanspecifiedinTable2,andallowthemtorelax
precondition the yarn in skein form.
in the standard atmosphere for testing textiles for at least 3 h.
9.7 Conditioning (Options 1 and 4 only)—Condition skeins
Then reel test skeins from the relaxed skeins, for the determi-
that have been preconditioned as directed in Section 9.6 in a
nation of yarn linear density.
standard atmosphere for testing textiles, 21 6 1°C [70 6 2°F]
9.2.3 Once the correct tension for reeling has been estab-
and 65 6 2% relative humidity, until moisture equilibrium is
lished for a specific type of yarn and package, subsequent
reached, that is, until the mass of the specimen increases by no
testing of that yarn on the same reel does not require recheck-
more than 0.1% after2hin that atmosphere.
ing of skein lengths.
9.8 Oven Drying (Options 2, 3, 5, 6, and 7)
9.3 Length of Test Skein:
9.3.1 For reels with perimeters of1mor1.5yd, select the 9.8.1 Place the skeins as reeled, or after scouring, in an
oven, maintained at 105 6 3°C [221 6 5°F]. Arrange the
number of wraps and skein length from Table 2. If a reel with
adifferentperimeterisusedbyagreement,selectthenumberof skeins to permit free air access.
wraps based on a whole number of turns of the reel, that will 9.8.2 Drytheskeinstoconstantmass,thatis,untiltheylose
give approximately one of the skein lengths shown in Table 2. no more than 0.1% of their mass at 15 min. intervals if
weighed in the oven, or at 30 min. intervals if weighed outside
NOTE 7—If both the skein breaking force and yarn linear density are to
the oven.
be determined, note that in certain cases, skein lengths shorter than those
9.8.2.1 Cooling in hot, closed containers in a dessicator
shown in Table 2 are permitted. For example, Option 1 of Test Method
D1578 specifies a skein length of 110 m [120 yd], but permits the use of
frequently c
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