1、Designation: D 2969 04Standard Test Methods forSteel Tire Cords1This standard is issued under the fixed designation D 2969; 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 parentheses indicate
2、s the year of last reapproval. Asuperscript epsilon (e) 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 agreement, these test
3、 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 of testing tire
4、cords and tire cord fabrics,refer to Methods D 885, Test Methods D 1871, Specifications D 122, andTest Methods D 2692 and D 2970. For tolerances on tire cords and tirecord fabrics, refer to Specifications D 122 and Methods D 885.1.2 These test methods include test procedures only; they donot establi
5、sh 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 X1Elongation at
6、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 with its use. It
7、 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 This standard is written in SI units. No other units ofmeasurement are included in this standard.2
8、. Referenced Documents2.1 ASTM Standards:2D 76 Specification for Tensile Testing Machines for TextilesD 122 Specifications for Tire Fabrics Other Than Tire CordFabrics3D 123 Terminology Relating to TextilesD 885 Methods of Testing Tire Cords, Tire Cord Fabrics,and Industrial Filament Yarns and Cords
9、 Made fromManufactured Organic-Based FibersD 1777 Test Method for Thickness of Textile MaterialsD 1871 Test Methods for Adhesion of Single-Filament SteelWire to RubberD 2229 Test Method for Adhesion Between Steel TireCords and RubberD 2692 Test Method for Air Wicking of Tire Fabrics, TireCord Fabric
10、s, Tire Cord, and YarnsD 2904 Practice for Interlaboratory Testing of a Textile TestMethod that Produces Normally Distributed DataD 2970 Methods of Testing Tire Cords, Tire Cord Fabricsand Industrial Yarns Made from Glass FilamentsD 4393 Test Method for Strap Peel Adhesion of ReinforcingCords or Fab
11、rics to Rubber CompoundsD 6477 Terminology Relating to Tire Cord, Bead Wire,Hose Reinforcing Wire, and FabricsE 663 Practice for Flame Atomic Absorption Analysis42.2 International Bureau for the Standardization of Man-Made Fibers (BISFA):Internationally Agreed Methods for Testing Steel TireCords53.
12、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 D 6477.1These test methods are under the jurisdiction of ASTM Committee D13 onTextiles and are the direct responsibility of Subcommittee D13.19 on Tire Co
13、rd andFabrics.Current edition approved Oct. 1, 2004. Published October 2004. Originallypublished as D 2969 71 T. Last previous edition D 2969 02.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards
14、volume information, refer to the standards Document Summary page onthe ASTM website.3Discontinued. See 1993 Annual Book of ASTM Standards, Vol 07.01.4Discontinued. See 1996 Annual Book of ASTM Standards, Vol 03.06.5Available from BISFA, Lauren Garten Strasse 12, PO Box, CH-4010 BASLESwitzerland.1Cop
15、yright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.1.1 The following terms are relevant to this standard:core, direction of lay, flare, high elongation, in steel tire cord,length of lay, residual torsion, steel cord, steel cord wrap, st
16、eelfilaments, steelstrand, straightness, in steel cord, and wildness.3.1.2 For definitions of other terms related to textiles, referto Terminology D 123.3.1.2.1 The following terms are relevant to this standard:direction of twist.4. Summary of Test Method4.1 A summary of the test methods prescribed
17、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 D 2969 for the deter-mination of the properties of steel tire cord and relatedmaterials are considered satisfactory for accep
18、tance testing ofcommercial shipments of such products because the proceduresare the best available and have been used extensively in thetrade. When a purchaser frequently uses a specific supplier, itis recommended that the two parties investigate the methods todetermine if there is any bias between
19、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 if there isa statistical bia
20、s 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. Test specimensshould then be
21、 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 found, either itscause must
22、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 sample for acceptance testing,tak
23、e at random the number of primary sampling units asdirected in an applicable material specification or other agree-ment between the purchaser and the supplier. Consider cartonsof cords or rolls of fabric as primary sampling units.NOTE 2A realistic specification or other agreement between thepurchase
24、r 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 risk,acceptable quality level,
25、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 between the purchaser and thesupp
26、lier.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 of1moffabric from the outside layer of the roll (see6.2.3).6.2.3 Place each laboratory sampling unit in a moisture-proof container to protect it from atmospheric corro
27、sion 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 otherpackages in the laboratory sample.7. Co
28、nditioning7.1 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 appearance and test procedures for resi
29、dualtorsion, 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 is taken from each laboratory sa
30、mplingunit 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 a right angle bend about 25 mm f
31、rom 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 cord on the package. Release the fr
32、ee 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 aspositive (+) and anti-clockwise r
33、otations 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 applied to the cord, place the cord
34、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.NOTE 3It is common practice to make residual torsion and straight-ness observations on the same speci
35、men. Residual torsion is measuredfirst, then straightness.D29690428.4.3 FlareCut a straight section of cord (not less than100 mm) using cutters6held at right angles to the axis of thespecimen and measure to the nearest 1 mm of the distancealong the longitudinal axis that any filament or strand unrav
36、-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, or 8.4.3 and recordthe presence of any dirt, rust, oil, or any other foreign material.Also look for and record any pitting, inclu
37、ding 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 MethodsD 2969. Describe the material sampled and the method usedfor sampling and report the follo
38、wing 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.8.6 Precision and BiasNo justifiable s
39、tatement can bemade either on the precision or bias of the procedures in TestMethods D 2969 for the evaluation of visual appearancebecause the test results merely state conformance to the criteriafor success specified in the procedures.8.6.1 Twenty cord samples of 2X.30 HT construction weremeasured
40、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 right-skewed distribution, with values b
41、e-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 0.22 0.62 NA NASris the intra-laboratory
42、 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”that can “reasonably” be expected betwee
43、n 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 test results are obtained from differ
44、entlaboratories.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 cordis used to calculate the expected mass of pneumatic ti
45、res andthe various components used in their manufacture as a part ofthe process 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 fromfabric, use a sufficient number of
46、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 linear density ofhigh-elongation cords
47、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 L0!/L0! (1)(4) Calculate and report
48、the linear density, as follows:Linear density, tex 5 M/L0! 3 1 1 EF! (2)where:M = mass, g,L (0) = length, km, andEF = extension factor.9.4 ProcedureDetermine the mass of the specimen ofcord by weighing to the nearest 1 mg.9.5 CalculationCalculate the linear density to the nearest10 tex using Eq 3:Li
49、near 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 D 2969. 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 four obser-vations, the difference between averages should not exceed 10tex in 95 out of 100 cases when all of the observations aret
