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ASTM D2731-07(2012)

(Test Method)

Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)

Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)

SIGNIFICANCE AND USE
This test method is considered satisfactory for acceptance testing of commercial shipments since current estimates of between-laboratory precision are acceptable and the method is used extensively in the trade for acceptance testing.
If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use samples for such comparative tests that are as homogeneous as possible, drawn from the same lot of material as the samples that resulted in disparate results during initial testing, and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.
Force at Specified Elongation (FASE) is a measure of the tensile force required to extend a textile material within specified limits. This characteristic of elastomeric yarn indicates the resistance that will have to be overcome by the wearer while putting on a garment made of the material and is also an indication of the garment's resistance to deformation caused by normal body movements during wear. The elongations used for these measurements are typically 100 %, 200 % and 300 %.
Permanent Deformation (set) is a measure of the increase in length of an elastomeric yarn resulting from cyclic stretching and relaxation. The characteristic is a visible indication of the realignment of intermolecular bonds within the elastic material. As with stress decay, the amount of set increases with yarn extension; however, for any particular extension, little or no additional set takes place after five cycles of exercising. ...
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1.1 This test method covers the determination of elastic properties of “as produced” elastomeric yarns made from rubber, spandex or other elastomers. Elastic properties include force at specified elongations, permanent deformation and stress decay. Other hysteresis related properties can be calculated.
Note 1—For a method designed specifically for testing rubber threads, refer to Test Method D2433.
1.2 This test method is not applicable to covered, wrapped, or core-spun yarns or yarns spun from elastomeric staple.
1.3 This test method is applicable to elastomeric yarns having a range of 40 to 3200 dtex (36 to 2900 denier).
1.4 The values stated in either SI units or U.S. Customary units are to be regarded separately as standard. Within the text, the U.S. Customary units are in parentheses. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
30-Jun-2012
ICS
59.080.20 - Yarns
Technical Committee
D13 - Textiles
Drafting Committee
D13.58 - Yarns and Fibers
Current Stage
Ref Project

Relations

Replaces
ASTM D2731-07 - Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)
Effective Date
01-Jul-2012

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ASTM D2731-07(2012) - Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)ASTM D2731-07(2012) - Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)
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ASTM D2731-07(2012) - Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)
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Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D2731 − 07(Reapproved 2012)
Standard Test Method for
Elastic Properties of Elastomeric Yarns (CRE Type Tensile
1
Testing Machines)
This standard is issued under the fixed designation D2731; 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.
3
1. Scope D2433 Test Methods for Rubber Thread (Withdrawn 2012)
D2591 Test Method for Linear Density of ElastomericYarns
1.1 This test method covers the determination of elastic
(Short Length Specimens)
properties of “as produced” elastomeric yarns made from
D2653 Test Method for Tensile Properties of Elastomeric
rubber, spandex or other elastomers. Elastic properties include
Yarns (CRE Type Tensile Testing Machines)
force at specified elongations, permanent deformation and
D4848 Terminology Related to Force, Deformation and
stress decay. Other hysteresis related properties can be calcu-
Related Properties of Textiles
lated.
D4849 Terminology Related to Yarns and Fibers
NOTE 1—For a method designed specifically for testing rubber threads,
D6717 Test Method for Linear Density of ElastomericYarns
refer to Test Method D2433.
(Skein Specimens)
1.2 This test method is not applicable to covered, wrapped,
3. Terminology
or core-spun yarns or yarns spun from elastomeric staple.
3.1 For all terminology relating to D13.58, Yarns and
1.3 This test method is applicable to elastomeric yarns
Fibers, refer to Terminology D4849.
having a range of 40 to 3200 dtex (36 to 2900 denier).
3.1.1 The following terms are relevant to this standard:
1.4 The values stated in either SI units or U.S. Customary
deformation, elastomeric yarn, elongation, force at specified
units are to be regarded separately as standard. Within the text,
elongation,lineardensity,permanentdeformation,stress,stress
the U.S. Customary units are in parentheses. The values stated
decay.
in each system are not exact equivalents; therefore, each
3.2 For definitions of other terms related to force and
system shall be used independently of the other.
deformation, refer to Terminology D4848. For all other terms
1.5 This standard does not purport to address all of the
related to textiles, refer to Terminology D123.
safety concerns, if any, associated with its use. It is the
4. Summary of Test Method
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
4.1 Aspecimen, mounted in a CRE-type tensile machine, is
bility of regulatory limitations prior to use.
initially subjected to a series of five loading/unloading cycles
in which the specimen is extended and relaxed between zero
2. Referenced Documents
and 75 % of the elongation at first filament break (FFB).
2
During the fifth cycle, the specimen is held at the maximum
2.1 ASTM Standards:
extension point for 30 s, then unloaded to allow a return to its
D76 Specification for Tensile Testing Machines for Textiles
original gage length position. The specimen is then subjected
D123 Terminology Relating to Textiles
to a sixth load/unload cycle.
D1776 Practice for Conditioning and Testing Textiles
D2258 Practice for Sampling Yarn for Testing
4.2 Force at specified elongations are calculated from the
force-elongation curve for the first and fifth loadings and for
thefifthunloading.Stressdecayiscalculatedonthefifthcycle.
Extension at a specified force is determined on the sixth
loading and is used to calculate the permanent deformation.
1
This test method is under the jurisdiction ofASTM Committee D13 on Textiles
and is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.
5. Significance and Use
Current edition approved July 1, 2012. Published August 2012. Originally
approved in 1968. Discontinued 1979 and reinstated as D2731 – 01. Last previous
5.1 This test method is considered satisfactory for accep-
edition approved in 2007 as D2731–07. DOI: 10.1520/D2731-07R12.
tance testing of commercial shipments since current estimates
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
3
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D2731 − 07 (2012)
of between-laboratory precision are acceptable and the method ofcycling,anddesignedforoperationatapullingspeedof500
is used extensively in the trade for accep
...

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SIGNIFICANCE AND USE
5.1 This is a quick method used for the determination of the approximate yarn number of short-length specimens taken from packages or fabrics.  
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5.1 Test Method D6612 for yarn number and yarn number variability is satisfactory for acceptance of commercial shipments and is used in the trade.  
5.1.1 If there are differences of practical significance between the reported test results for two or more laboratories, comparative tests should be performed by those laboratories to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, samples used for each comparative tests should be as homogeneous as possible, drawn from the same lot of material as the samples that results in disparate results during initial testing, and randomly assigned in equal numbers to each laboratory. Other fabrics with established tests values are used for this purpose. The test results from the laboratories involved should be compared appropriate statistical analysis and a probability level chosen by the two parties before testing begins, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results adjusted in consideration of the known bias.  
5.1.2 The average results from the two laboratories should be compared using appropriate statistical analysis and a probability level chosen by the two parties before the testing is begun. If a bias is found, either its cause must be found and corrected or the purchaser and the supplier must agree to interpret future test results with consideration to the known bias.  
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5.3 Indices of Variability:  
5.3.1 Coefficient of Variation—%CV is a standard statistical calculation and is the most common index of yarn unevenness. For most textile applications in the 80 to 330 dtex (70 to 300 denier) range, a 1.0 to 1.3 %CV is adequate. %CV of yarns coarser than 666 dtex (600 denier) is not routine and usually not meaningful. %CV is less discriminating that %DS.  
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1.2 Yarn number variability properties include percent density spread (%DS), coefficient of variation (%CV), density frequency variation.  
Note 1: For determination of yarn number by use of reel and balance, refer to Test Method D1907. For another method of measuring variability (unevenness) in yarn, refer to Test Method D1425.  
1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore to ensure conformance with this standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
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ASTM D1423/D1423M-16(2022)(Test Method)
Standard Test Method for Twist in Yarns by Direct-Counting

SIGNIFICANCE AND USE
5.1 Test Method D1423 for testing twist in yarns by direct-counting is considered satisfactory for acceptance testing of commercial shipments because current estimates of between-laboratory precision are acceptable and the method has been used extensively in the trade for acceptance testing.  
5.1.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum use the samples for such comparative tests as homogeneous as possible, drawn from the same lot of material that resulted in the disparate test results and randomly in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If a bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.  
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1.3 This test method is not intended for yarns that extend more than 5.0 % when tension is increased from 2.5 to 7.5 mN/tex [0.25 to 0.75 gf/tex]. Following the procedures of this test method for such yarns would be independent of the bias and precision determined for this test method. The report from such testing should include the tension used for this testing.  
1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.
Note 1: For a more rapid but less accurate method of determining twist in single spun yarns, refer to Test Method D1422.
Note 2: This test method has been evaluated for use in de...

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ASTM D2258/D2258M-16(2022)(Practice)
Standard Practice for Sampling Yarn for Testing

SIGNIFICANCE AND USE
5.1 Assigning a value to any property of the material in a container or in a lot, consignment, or delivery involves a measurement process that includes both sampling and testing procedures. The correctness of the value assigned depends upon the variability due to testing and sampling plan. Even when the variability due to testing is minimized by carefully developed procedures, correct and consistent estimates of the true value of the property are possible only when the sampling procedure avoids systematic bias, minimizes variations due to sampling, and provides a laboratory sample of adequate size.  
5.2 Practice D2258 may not give the most efficient sampling plan that might be devised in special situations but does present a general procedure that gives satisfactory precision with an economical amount of sampling. Many plans that include stratified sampling can be found in textbooks and through the use of statistical software tools and calculators.  
5.2.1 If not specified by the purchaser, the manufacturer will define suitable production lots based on one or more of the following: supply lot, production shift/time segment, production equipment or production line, operator, designated shipment, production run, or a combination herein.  
5.2.2 If not specified by the purchaser, the manufacturer will define sampling and testing frequency based on the following: process capability or capability analysis, historical trends, level of detection rate required, confidence level requirements, known variations or special causes, or both. Every attempt to ensure conforming product is being produced, identify potential nonconforming product or proper isolation and identification, will be carried out by the manufacturer.  
5.2.3 Sampling count and number of specimens will be based on standard practice listed within the document. Increase or decrease in count or frequency might be applied based on typical standard deviation, precision and confidence level, Measurement System...
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1.1 This practice describes a procedure for the division of shipments of yarn into test lots and the sampling of such lots for testing.  
1.1.1 This practice can be used for lot sample testing of yarns for both pre-fabric production and post-fabric production.  
1.2 This practice is applicable to single, plied, or cabled yarns, and cords, made of any fiber or mixture of fibers, and supported on any form of package, including beams.  
1.3 This practice also describes procedures for the sampling of yarn(s) removed from woven or knitted fabrics; however, when thus sampled, the yarns are usually not representative of entire shipments, as referred to in 1.1. Consequently, the resultant sampling can only be used to determine the characteristics of the yarn and is usually not used for acceptance testing. Moreover, it should be recognized that the characteristics of yarns from fabrics may be different than the characteristics of the same yarn(s), prior to being entered into the fabric manufacturing process.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 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...

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ASTM
ASTM D3693-02(2021)(Specification)
Standard Specification for Labeled Length per Holder of Sewing Thread

ABSTRACT
This specification covers the requirements for the labeled lengths per holder of sewing threads of all materials. The test specimen is a thread holder whether a cone, tube, spool, ready-made bobbin, or any other holders. The observed length for all holders such as home sewing spools, ready-made bobbins, or all other holders which depends on the sampling size shall equal or exceed a certain percentage of the minimum allowable labeled length.
SCOPE
1.1 This specification covers requirements for the labeled lengths of sewing threads of all materials.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 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.

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ASTM D2731-21(Test Method)
Standard Test Method for Elastic Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)

SIGNIFICANCE AND USE
5.1 This test method is considered satisfactory for acceptance testing of commercial shipments since current estimates of between-laboratory precision are acceptable and the method is used extensively in the trade for acceptance testing.  
5.1.1 If there are differences of practical significance between reported test results for two laboratories (or more), comparative tests should be performed to determine if there is a statistical bias between them, using competent statistical assistance. As a minimum, use samples for such comparative tests that are as homogeneous as possible, drawn from the same lot of material as the samples that resulted in disparate results during initial testing, and randomly assigned in equal numbers to each laboratory. The test results from the laboratories involved should be compared using a statistical test for unpaired data, at a probability level chosen prior to the testing series. If bias is found, either its cause must be found and corrected, or future test results for that material must be adjusted in consideration of the known bias.  
5.2 Force at Specified Elongation (FASE) is a measure of the tensile force occurring while extending a textile material within specified limits. This characteristic of elastomeric yarn indicates the resistance that will have to be overcome by the wearer while putting on a garment made of the material and is also an indication of the garment's resistance to deformation caused by normal body movements during wear. The elongations used for these measurements are typically 100 %, 200 % and 300 %.  
5.3 Permanent Deformation (set) is a measure of the increase in length of an elastomeric yarn resulting from cyclic stretching and relaxation. The characteristic is a visible indication of the realignment of intermolecular bonds within the elastic material. As with stress decay, the amount of set increases with yarn extension; however, for any particular extension, little or no additional set takes place after...
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1.1 This test method covers the determination of elastic properties of “as produced” elastomeric yarns made from rubber, spandex or other elastomers. Elastic properties include force at specified elongations, permanent deformation and stress decay. Other hysteresis related properties can be calculated.
Note 1: For a method designed specifically for testing rubber threads, refer to Test Method D2433.  
1.2 This test method is not applicable to covered, wrapped, or core-spun yarns or yarns spun from elastomeric staple.  
1.3 This test method is applicable to elastomeric yarns having a range of 40 to 3200 dtex (36 to 2900 denier).  
1.4 The values stated in either SI units or U.S. Customary units are to be regarded separately as standard. Within the text, the U.S. Customary units are in parentheses. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 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.

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