ASTM A931-2008 Standard Test Method for Tension Testing of Wire Ropes and Strand《金属丝绳和绞线拉伸试验的标准试验方法》.pdf

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1、Designation: A 931 08Standard Test Method forTension Testing of Wire Ropes and Strand1This standard is issued under the fixed designation A 931; 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

2、 parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the tension testing of wire ropesand strand at room temperature, specifically to determine themeasured breaking force,

3、yield strength, elongation, and modu-lus of elasticity. Methods described in this standard are notintended for other purposes.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for informa

4、tion onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with 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

5、 limitations prior to use. Specific precau-tionary statements are given in Note 1 and Note 2.2. Referenced Documents2.1 ASTM Standards:2A 586 Specification for Zinc-Coated Parallel and HelicalSteel Wire Structural StrandA 603 Specification for Zinc-Coated Steel Structural WireRopeA 1023/A 1023M Spec

6、ification for Stranded Carbon SteelWire Ropes for General PurposesB 6 Specification for ZincE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical Test-ingE8 Test Methods for Tension Testing of Metallic Materials2.2 ISO Standard3ISO 17558 Specificatio

7、n for Steel Wire Ropes SocketingProcedures Molten Metal and Resin Socketing3. Terminology3.1 The terminology relating to tensile testing in Terminol-ogy E6applies to this test method. In addition, the followingdefinitions for wire rope will apply:3.2 Definitions:3.2.1 abrasionfrictional surface wear

8、 on the wires of awire rope.3.2.2 aggregate areasee area, metallic.3.2.3 aggregate strengththe strength derived by totalingthe individual breaking strengths of the elements of the strandor rope. This strength does not give recognition to thereduction in strength resulting from the angularity of thee

9、lements in the rope, or other factors that may affect efficiency.3.2.4 area, metallicsum of the cross-sectional areas of allwires either in a wire rope or in a strand.3.2.5 breaking forcethe maximum load at which a tensilefailure occurs in the sample of wire rope being tested.3.2.5.1 DiscussionThe t

10、erm breaking force is synony-mous with actual strength.3.2.6 cablea term loosely applied to wire rope, wirestrand, and electrical conductors.3.2.7 centerthe axial member of a strand about which thewires are laid.3.2.8 classificationgroup or family designation based onwire rope constructions with com

11、mon strengths and weightslisted under the broad designation.3.2.9 constructiongeometric design description of thewire ropes cross section. This includes the number of strands,the number of wires per strand, and the pattern of wirearrangement in each strand.3.2.10 corethe axial member of a wire rope

12、about whichthe strands are laid.1This test method is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.03 on Steel Rod and Wire.Current edition approved Oct. 1, 2008. Published October 2008. Originallyapproved

13、 in 1994. Last previous edition approved in 2008 as A 931 96 (2008).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM w

14、ebsite.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,

15、 United States.3.2.11 fiber corecord or rope of vegetable or syntheticfiber used as the core of a rope.3.2.12 gradewire rope or strand classification by strengthor type of material, that is, Class 3, Type 302 stainless,phosphor bronze, etc. It does not apply to strength of theindividual wires used t

16、o manufacture the rope or strand.3.2.13 independent wire rope core (IWRC)a wire ropeused as the core of a larger wire rope.3.2.14 inner wiresall wires of a strand except the outer orcover wires.3.2.15 lay(a) the manner in which the wires in a strand orthe strands in a rope are helically laid, or (b)

17、 the distancemeasured parallel to the axis of the rope (or strand) in which astrand (or wire) makes one complete helical convolution aboutthe core (or center). In this connection, lay is also referred to aslay length or pitch.3.2.16 minimum breaking forcespecified value that thebreaking force must m

18、eet or exceed in a prescribed test.3.2.17 modulus of elasticitythe slope of the elastic portionof the stress-strain curve. The ratio of stress to correspondingstrain below the proportional limit. This value is generallytaken between 20 and 50 % of the minimum breaking force.3.2.18 socketgeneric name

19、 for a type of wire rope fitting.3.2.19 stranda plurality of round or shaped wires heli-cally laid about a center.3.2.20 wire ropestrands helically laid around a core.3.2.21 wire strand core (WSC)a wire strand used as thecore of a wire rope.3.2.22 zinc-coated (galvanized) ropewire rope made upof zin

20、c coated (galvanized) wire.3.2.23 zinc coated (galvanized) strandstrand made up ofzinc-coated (galvanized) wire.4. Significance and Use4.1 Wire rope tests are generally to be performed on newrope. The use of wire rope in any application can reduceindividual wire strengths due to abrasion and nicking

21、 that willresult in the wire rope strength being reduced. Damage to theouter wires will also lower the maximum strength achievedduring tension testing.4.2 The modulus of elasticity of wire rope is not consideredto be a standard requirement at this time. The determination ofthis material property req

22、uires specialized equipment andtechniques.4.3 Rope to be tested should be thoroughly examined toverify that no external wire damage is present. If present, itshould be noted. When possible, a new undamaged sampleshould be obtained for testing.4.4 End attachments and their installation can directly a

23、ffectbreaking force achieved during testing. Any attachment thatcan be used to directly achieve the required rope breaking forcecan be used. Standard testing with a poured socket, using zinc,white metal or thermoset resin, has been considered the mostefficient. Proficiency in attachment of any fitti

24、ng can have adirect effect on the final test results.5. Interferences5.1 Visual examination of the sample for any damage toouter wires should be done. If any damage is evident, thesample should not be used.5.2 Measurement of the rope or strand sample is necessaryto document the size, length between

25、end attachments, andlength of lay of the rope if necessary. Further details regardingthis will be discussed in test results.5.3 The length of test specimen shall not be less than 3 ft,(0.91 m) between sockets for wire ropes up to 1 in. (25.4 mm)diameter, inclusive, and not less than 5 ft (1.52 m) be

26、tweensockets for wire ropes 118 in. (28.6 mm) to 3 in. (77 mm)diameter. On wire ropes larger than 3 in. (77 mm), the clearlength of the test specimen shall be at least 20 times the ropediameter.6. Apparatus6.1 Testing MachinesMachines used for tension testingshall conform to the requirements of Prac

27、tices E4. The loadsused in determining tensile strength and yield strength shall bewithin loading range of the tensile machine as defined inPractices E4.6.2 Gripping Devices:6.2.1 GeneralVarious types of gripping devices may beused to transmit the measured load applied by the testingmachine to test

28、specimens. To ensure axial tensile stress withinthe gage length, the axis of the test specimen should coincidewith the center line of the heads of the machine. Any departurefrom this requirement may introduce bending stresses that arenot included in the usual stress computation.6.2.2 Wedge GripsTest

29、ing machines usually are equippedwith wedge grips. These wedge grips generally furnish asatisfactory means of gripping long specimens of ductile metal.If, however, for any reason, one grip of a pair advances fartherthan the other as the grips tighten, an undesirable bendingstress may be introduced.

30、When liners are used behind thewedges, they must be of the same thickness and their facesmust be flat and parallel. For best results, the wedges should besupported over their entire lengths by the heads of the testingmachine. This requires that liners of several thicknesses beavailable to cover the

31、range of specimen thickness. For propergripping, it is desirable that the entire length of the serratedface of each wedge be in contact with the specimen. Specially-designed round-shaped grips may have to be used for testingrope or strand. It is essential that all wires in the rope or strandare unif

32、ormly gripped when the load is applied.6.2.3 Conical GripsConical grips are constructed so thatwhen they are fitted together, a conical-shaped cavity existswhich will hold a cone socket wire rope or strand andattachment (fitting).7. Sample End Terminations7.1 Poured sockets or swaged sockets are typ

33、ically used intensile tests. Properly prepared, they are 100% efficient. Othertypes of end terminations may be used as long as the requiredminimum breaking force is achieved. Refer to ISO 17558 forsocketing procedures.A9310828. Procedure8.1 Take measurements on the sample to determine theactual rope

34、 diameter and sample length between sockets beforeloading on the test machine.NOTE 1Rope diameter should be measured properly to determine theactual diameter. (See Fig. 1 for the correct method.) An incorrectmeasurement is possible and should be avoided. (See Fig. 2 for the methodto avoid.)8.2 After

35、 the sample is placed in the test machine, completethe zeroing before testing begins for accurate results. Startapplying the load to the sample. The maximum rate of loadingshould be 0.032 in. per minute (0.032 mm per min) for each in.(mm) of test gage length when the rate is under the operatorcontro

36、l (a typical test gage length is 60 in. (1524 mm). Applythe load until a reduction from a maximum reading occurs.This reduction will normally be accompanied by a noise whenwires and strand break. Wire and lubricant will be thrown fromthe sample if not contained.NOTE 2Warning: Safety in tensile testi

37、ng of wire rope should be amajor concern for the operator of the test machine, observers and thesurroundings. Uncontained wires, during testing, can impact and penetrateobjects at a great distance. Adequate safety shields directly around thesample, as well as around the operator and observers, shoul

38、d be used at aminimum.8.2.1 The measured breaking force is reached when nofurther increase in applied force is possible. After the initialfailure of some strands, the sample has reached its maximumstrength. It is not necessary to continue the test until all strandsin the sample have failed.NOTE 3Ver

39、ification of meeting the required Minimum BreakingForce is achieved once the applied force to the test specimen meets orexceeds the required Minimum Breaking Force. It is not necessary toobtain the measured breaking force of the specimen to verify conform-ance.8.2.2 The test may be discounted when t

40、he rope strandfracture occurs within a distance equivalent of 6 rope diametersor 10 strand diameters from the base of the grip or thetermination and the intended minimum breaking force has notbeen reached.8.3 If the sample being evaluated does not meet the mini-mum breaking force, additional samples

41、 may be tested. Retestinstructions are detailed in Specifications A 586, A 603 andA 1023.8.4 Final tensile test results are normally measured inpounds.9. Precision and Bias9.1 The primary intent of testing wire ropes and strand is toensure that the wire rope or strand will meet the specifiedbreaking

42、 force. Sometimes yield strength, elongation, or modu-lus of elasticity is required or desired. In the case of zinc coatedstructural strand and zinc coated structural rope tested to meetthe requirements in Specifications A 586 and A 603, theprocedures for determining percent elongation and modulus o

43、felasticity and gage lengths are specified in SpecificationsA 586and A 603.9.1.1 When yield strength is needed, the methods defined inTest Methods E8are recommended.9.2 PrecisionThe precision of this test method has notbeen determined.9.3 BiasThe bias of this test method includes quantitativeestimat

44、es of the uncertainties of the dimensional measuringdevices, the calibrations of testing equipment and the skill ofthe operators. At this time, the statements on bias should belimited to documented performance of particular laboratories.10. Keywords10.1 socket; thermo-set resin; wire ropeFIG. 1 Corr

45、ect MeasurementFIG. 2 Incorrect MeasurementA931083SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue (A 931 96(2002) that may impact the use of this standard. (Approved October 1, 2008.)(1) Deleted Figure 1.(2) Changed “acceptance st

46、rength” to “breaking force”throughout the standard.(3) Added Specification A 1023 and ISO 17558 to ReferencedDocuments in Section 2.(4) Revised Section 7in doing so, deleted Notes 1, 2 and 3.(5) Deleted Section 8. Renumbered subsequent sections.(6) Changed “galvanized” to “zinc-coated” throughout th

47、estandard.(7) Added Note 3.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infri

48、ngement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standar

49、d or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multipl