1、Designation: D2969 04 (Reapproved 2014)Standard Test Methods forSteel Tire Cords1This standard is issued under the fixed designation D2969; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pare
2、ntheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods cover the testing of cords made fromsteel that are specifically designed for use in the reinforcementof pneumatic tires. By agreem
3、ent, these test methods may beused to test similar cords or filaments used for reinforcing otherrubber products. The steel cords may be wound on spools orbeams. The steel cords may also be woven into fabric, in whichcase they must be removed from the fabric prior to testing.NOTE 1For other methods o
4、f testing tire cords and tire cord fabrics,refer to Methods D885, Test Methods D1871, Specifications D122, andTest Methods D2692 and D2970/D2970M. For tolerances on tire cordsand tire cord fabrics, refer to Specifications D122 and Methods D885.1.2 These test methods include test procedures only; the
5、y donot establish specifications or tolerances.1.3 This test method includes the following sections:Subject SectionAdhesion of Steel Cords and Filaments to Elastomers 16Brass Coating Composition and Mass 14, 15Breaking Force (Strength) 10Construction 12Data Form for Reporting Test Results Appendix X
6、1Elongation at Break 10Elongation Between Defined Forces (EDF) 11Flare 8Lay 12Linear Density 9Visual Appearance 8Nomenclature System Annex A1Residual Torsions 8Straightness 8Thickness and Out-of-Roundness 131.4 This standard does not purport to address all of thesafety concerns, if any, associated w
7、ith its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. See 14.3 and Note11.1.5 The values stated in SI units are to be regarded asstandard. No other units of meas
8、urement are included in thisstandard.2. Referenced Documents2.1 ASTM Standards:2D76 Specification for Tensile Testing Machines for TextilesD122 Tolerances for Tire Fabrics Other Than Tire CordFabrics (Withdrawn 1993)3D123 Terminology Relating to TextilesD885 Test Methods for Tire Cords, Tire Cord Fa
9、brics, andIndustrial Filament Yarns Made from ManufacturedOrganic-Base FibersD1871 Test Method for Adhesion Between Tire Bead Wireand RubberD2229 Test Method for Adhesion Between Steel Tire Cordsand RubberD2692 Test Method for Air Wicking of Tire Fabrics, TireCord Fabrics, Tire Cord, and YarnsD2904
10、Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed Data (With-drawn 2008)3D2970/D2970M Test Methods for Testing Tire Cords, TireCord Fabrics, and Industrial Yarns Made From GlassFilamentsD4393 Test Method for Strap Peel Adhesion of ReinforcingCords or Fab
11、rics to Rubber CompoundsD6477 Terminology Relating to Tire Cord, Bead Wire, HoseReinforcing Wire, and FabricsE663 Practice for FlameAtomicAbsorptionAnalysis (With-drawn 1997)32.2 International Bureau for the Standardization of Man-Made Fibers (BISFA):Internationally Agreed Methods for Testing Steel
12、TireCords43. Terminology3.1 Definitions:3.1.1 For definitions of terms relating to tire cord, bead wire,hose wire, and tire cord fabrics, refer to Terminology D6477.1These test methods are under the jurisdiction of ASTM Committee D13 onTextiles and are the direct responsibility of Subcommittee D13.1
13、9 on IndustrialFibers and Metallic Reinforcements.Current edition approved May 15, 2014. Published June 2014. Originallyapproved in 1971. Last previous edition approved in 2010 as D2969 04(2010).DOI: 10.1520/D2969-04R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact
14、ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.4Available from BISFA, Lauren Garten Strasse 12, PO Box,
15、CH-4010 BASLESwitzerland.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.1.1 The following terms are relevant to this standard:core, direction of lay, flare, high elongation, in steel tire cord,length of lay, residual torsion, ste
16、el cord, steel cord wrap, steelfilaments, steelstrand, straightness, in steel cord, and wildness.3.1.2 For definitions of other terms related to textiles, referto Terminology D123.3.1.2.1 The following terms are relevant to this standard:direction of twist.4. Summary of Test Method4.1 A summary of t
17、he test methods prescribed for thedetermination of specific properties is stated in each of thesections pertaining to the respective properties.5. Significance and Use5.1 The procedures in Test Methods D2969 for the determi-nation of the properties of steel tire cord and related materialsare conside
18、red satisfactory for acceptance testing of commer-cial shipments of such products because the procedures are thebest available and have been used extensively in the trade.When a purchaser frequently uses a specific supplier, it isrecommended that the two parties investigate the methods todetermine i
19、f there is any bias between their two laboratories asdirected in 5.1.1.5.1.1 In case of a dispute arising from differences inreported test results when using this test method for acceptancetesting of commercial shipments, the purchaser and the sup-plier should conduct comparative tests to determine
20、if there isa statistical bias between their laboratories. Competent statis-tical assistance is recommended for the investigation of bias.As a minimum, the two parties should take a group of testspecimens that are as homogeneous as possible and that arefrom a lot of material of the type in question.
21、Test specimensshould then be randomly assigned in equal numbers to eachlaboratory for testing. The average results from the twolaboratories should be compared using the appropriate statis-tical analysis and an acceptable probability level chosen by thetwo parties before testing is begun. If bias is
22、found, either itscause must be found and corrected or the purchaser and thesupplier must agree to interpret future test results with consid-eration to the known bias.5.2 The significance and use of particular properties arediscussed in the appropriate sections.6. Sampling6.1 Lot SampleAs a lot sampl
23、e for acceptance testing, takeat random the number of primary sampling units as directed inan applicable material specification or other agreement be-tween the purchaser and the supplier. Consider cartons of cordsor rolls of fabric as primary sampling units.NOTE 2A realistic specification or other a
24、greement between thepurchaser and the supplier requires taking into account the variabilitybetween cartons of cords and between spools or other packages within acarton, or the variability between and within rolls of fabric so as to providea sampling plan with meaningful producers risk, consumers ris
25、k,acceptable quality level, and limiting quality level.6.2 Laboratory SampleAs a laboratory sample for accep-tance testing, proceed as follows:6.2.1 For cords, take at random the number of spools orother packages per carton as directed in the applicable materialspecification or other agreement betwe
26、en the purchaser and thesupplier.6.2.2 For fabric, take a full-width swatch 1 m long from theend of each roll in the lot sample, after first discarding aminimum of 1 m of fabric from the outside layer of the roll (see6.2.3).6.2.3 Place each laboratory sampling unit in a moisture-proof container to p
27、rotect it from atmospheric corrosion andcontamination.6.3 Test SpecimensTake the number of specimens fromeach laboratory sampling unit as directed in each specific testmethod.6.4 Specimen PreparationFor cords, when practical, per-form tests on specimens taken directly from the spools or otherpackage
28、s in the laboratory sample.7. Conditioning7.1 Conditioning of materials covered by these test methodshas not been found necessary, except to maintain cleanliness.8. Visual Appearance, Residual Torsion, Straightness,Flare8.1 ScopeThis test method covers the visual examinationof steel cord for appeara
29、nce and test procedures for residualtorsion, straightness, and flare.8.2 Significance and UsePhysical properties of steel tirecord may be affected by the methods of manufacturing andhandling procedures. Cleanliness has a direct effect on theadhesion of steel tire cord to elastomers.8.3 One specimen
30、is taken from each laboratory samplingunit for residual torsion, flare, and straightness. Specimens forother tests may be used for visual appearance.8.4 Procedures:8.4.1 Residual TorsionDetermine residual torsion by re-moving at least3mofcord from the package, cutting it off, anddiscarding it. Make
31、a right angle bend about 25 mm from thecord end on the package. Hold this bent end tightly so that itcannot turn while pulling out a specimen having a length of 66 0.2 m. Pull the specimen from the package in such a mannerthat does not change the residual torsions of the specimen fromthat of the cor
32、d on the package. Release the free end of the cordand allow this end to rotate while the cord is free of externaltension. Count and record the number of rotations of the cordend to the closest one-half rotation and, viewing the cord fromthe bent end toward the package, denote clockwise rotations asp
33、ositive (+) and anti-clockwise rotations as negative ().8.4.1.1 Calculate the average residual torsion for the lot.8.4.2 StraightnessWithout cutting the specimen from thepackage, pull out a length of cord 66 0.2 m and lay it on asmooth, hard surface and allow it to rotate freely. With notension appl
34、ied to the cord, place the cord specimen approxi-mately equidistant from two straight parallel lines spaced at adistance of 75 6 3 mm. If the specimen does not touch bothlines consider the specimen straight. Record the observation.D2969 04 (2014)2NOTE 3It is common practice to make residual torsion
35、and straight-ness observations on the same specimen. Residual torsion is measuredfirst, then straightness.8.4.3 FlareCut a straight section of cord (not less than 100mm) using cutters5held at right angles to the axis of thespecimen and measure to the nearest 1 mm of the distancealong the longitudina
36、l axis that any filament or strand unrav-elled. Record this distance.8.4.3.1 Calculate the average flare for the lot.8.4.4 ContaminationMake a visual inspection of thespecimen taken as directed in 8.4.1, 8.4.2,or8.4.3 and recordthe presence of any dirt, rust, oil, or any other foreign material.Also
37、look for and record any pitting, including rough spots. Avisual inspection of the package and its integrity may beincluded, if appropriate.8.5 ReportState that the inspection of visual appearancewas made in accordance with Section 8 of Test MethodsD2969. Describe the material sampled and the method
38、used forsampling and report the following information:8.5.1 Residual Torsion, for each sampling unit and the lot.8.5.2 Straightness, for each sampling unit and the lot.8.5.3 Flare, for each sampling unit and the lot.8.5.4 ContaminationVisual appearance observations foreach laboratory sampling unit.8
39、.6 Precision and BiasNo justifiable statement can bemade either on the precision or bias of the procedures in TestMethods D2969 for the evaluation of visual appearance be-cause the test results merely state conformance to the criteriafor success specified in the procedures.8.6.1 Twenty cord samples
40、of 2X.30 HT construction weremeasured for residual torsion and flare in accordance with 8.4.1and 8.4.2. A single operator in a single laboratory performedthe testing. A statistical analysis was used to quantify intral-aboratory variability for these properties. The property flareshowed a strongly ri
41、ght-skewed distribution, with values be-tween 0 and 65 mm; the median value was 3 mm. Repeatabilitywas not calculated for flare because of its non-normal distri-bution. Results are shown in the following:Property Average SrRepeatability SRReproducibilityFlare 8.6 16.3 - NA NAResidual Torsion 1.45 0.
42、22 0.62 NA NASris the intra-laboratory standard deviation. SR, the totalstandard deviation, is formed by taking the square root of thesum of intra-laboratory and interlaboratory variance compo-nents. SRcannot be determined from these data.Method repeatability is defined as the “maximum difference”th
43、at can “reasonably” be expected between two test resultsobtained on the same material when the test results areobtained in the same laboratory. Method reproducibility isdefined as the “maximum difference” that can “reasonably” beexpected between two test results obtained on the samematerial when the
44、 test results are obtained from differentlaboratories.9. Linear Density9.1 ScopeIn this test method, a specified length of steelcord is weighed using an analytical balance and linear densityis calculated as mass per unit length.9.2 Significance and UseThe linear density of steel cord isused to calcu
45、late the expected mass of pneumatic tires and thevarious components used in their manufacture as a part of theprocess control procedure.9.3 Number and Preparation of SpecimensTake a speci-men having a minimum length of 1 m from each sample ofcord (see Note 4 for high-elongation cords). For samples f
46、romfabric, use a sufficient number of ends to give a minimumlength of1mofcord for each specimen. Measure the length ofthe specimen to within 0.1 % using a tension of 10 6 1Ntokeep the cord straight. Cut the specimen at the required length.Record the length.NOTE 4A proposed method for measuring the l
47、inear density ofhigh-elongation cords is as follows:(1) Clamp an extensometer onto the specimen that is straight, but underno tension; read the gage length L (0);(2)Apply a tension of 1.5 6 0.2 N to the cord and read the gage length,L (1);(3) Calculate the extension factor, EF, as follows:EF 5 L1! 2
48、 L0!/L0! (1)(4) Calculate and report the linear density, as follows:Linear density, tex 5 M/L0! 3 11EF! (2)where:M = mass, g,L (0) = length, km, andEF = extension factor.9.4 ProcedureDetermine the mass of the specimen of cordby weighing to the nearest 1 mg.9.5 CalculationCalculate the linear density
49、 to the nearest10 tex using Eq 3:Linear density, tex 5 M/L (3)where:M = mass, g, andL = length, km.9.5.1 Calculate the average linear density for the lot.9.6 ReportReport that the specimen was tested in accor-dance with Section 9 of Test Methods D2969. Describe thematerial sampled and the method of sampling used. Report thelinear density for each laboratory sampling unit and for the lot.9.7 Precision and Bias:9.7.1 SummaryIn comparing two averages of fourobservations, the difference between averages should notexceed 10 tex in 95 out of 100 cases w
