ASTM A931-2008(2013) 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

1、Designation: A931 08 (Reapproved 2013)Standard Test Method forTension Testing of Wire Ropes and Strand1This standard is issued under the fixed designation A931; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis

2、ion. A number in 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

3、breaking force, 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 prov

4、ided for information 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-bili

5、ty of regulatory limitations prior to use. Specific precau-tionary statements are given in Note 1 and Note 2.2. Referenced Documents2.1 ASTM Standards:2A586 Specification for Zinc-Coated Parallel and HelicalSteel Wire Structural StrandA603 Specification for Zinc-Coated Steel Structural WireRopeA1023

6、/A1023M Specification for Stranded Carbon SteelWire Ropes for General PurposesB6 Specification for ZincE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE8 Test Methods for Tension Testing of Metallic Materials2.2 ISO Standard3ISO 17558 Sp

7、ecification for Steel Wire Ropes SocketingProcedures Molten Metal and Resin Socketing3. Terminology3.1 The terminology relating to tensile testing in Terminol-ogy E6 applies to this test method. In addition, the followingdefinitions for wire rope will apply:3.2 Definitions:3.2.1 abrasionfrictional s

8、urface wear 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 angular

9、ity of theelements 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 Disc

10、ussionThe term 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 constructio

11、ns with common 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

12、 wire rope about whichthe strands are laid.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 o

13、f theindividual wires used to manufacture the rope or strand.3.2.13 independent wire rope core (IWRC)a wire ropeused as the core of a larger wire rope.1This test method is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of Sub

14、committeeA01.03 on Steel Rod and Wire.Current edition approved April 1, 2013. Published April 2013. Originallyapproved in 1994. Last previous edition approved in 2008 as A931 08. DOI:10.1520/A0931-08R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Ser

15、vice at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.*A Summary of Changes section a

16、ppears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.14 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 a

17、re helically laid, or (b) 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

18、 thebreaking force must meet 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.

19、3.2.18 socketgeneric name for a type of wire rope fitting.3.2.19 stranda plurality of round or shaped wires helicallylaid 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) rope

20、wire rope made up ofzinc 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

21、to abrasion and nicking 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 ofthi

22、s material property requires 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 inst

23、allation can directly affectbreaking 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

24、attachment of any fitting 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 th

25、e size, length between 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 les

26、s than 5 ft (1.52 m) betweensockets 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 t

27、he requirements of Practices 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

28、testingmachine to test 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 computatio

29、n.6.2.2 Wedge GripsTesting 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 bendingstr

30、ess may be introduced. 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 be

31、available to cover the 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

32、 rope or strandare uniformly 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

33、 swaged sockets are typically 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.8. Procedure8.1 Take measurements on the sample to determi

34、ne theactual rope diameter and sample length between sockets beforeloading on the test machine.NOTE 1Rope diameter should be measured properly to determine theA931 08 (2013)2actual diameter. (See Fig. 1 for the correct method.) An incorrectmeasurement is possible and should be avoided. (See Fig. 2 f

35、or the methodto avoid.)8.2 After 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

36、rate is under the operatorcontrol (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 2

37、Warning: Safety in tensile testing 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 t

38、he operator and observers, should 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

39、the sample have failed.NOTE 3Verification of meeting the required Minimum Breaking Forceis achieved once the applied force to the test specimen meets or exceedsthe required Minimum Breaking Force. It is not necessary to obtain themeasured breaking force of the specimen to verify conformance.8.2.2 Th

40、e test may be discounted when the 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 bre

41、aking force, additional samples may be tested. Retestinstructions are detailed in Specifications A586, A603 andA1023/A1023M.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 str

42、and will meet the specifiedbreaking 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 A586 and A603, the proce-dures for determini

43、ng percent elongation and modulus ofelasticity and gage lengths are specified in Specifications A586and A603.9.1.1 When yield strength is needed, the methods defined inTest Methods E8 are recommended.9.2 PrecisionThe precision of this test method has notbeen determined.9.3 BiasThe bias of this test

44、method includes quantitativeestimates 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; the

45、rmo-set resin; wire ropeFIG. 1 Correct MeasurementFIG. 2 Incorrect MeasurementA931 08 (2013)3SUMMARY OF CHANGESCommittee A01 has identified the location of selected changes to this standard since the last issue (A931 96(2002) that may impact the use of this standard. (Approved October 1, 2008.)(1) D

46、eleted Figure 1.(2) Changed “acceptance strength” to “breaking force”throughout the standard.(3) Added Specification A1023/A1023M and ISO 17558 toReferenced Documents in Section 2.(4) Revised Section 7in doing so, deleted Notes 1, 2 and 3.(5) Deleted Section 8. Renumbered subsequent sections.(6) Cha

47、nged “galvanized” to “zinc-coated” throughout thestandard.(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

48、 of any such patent rights, and the riskof infringement 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

49、 are invited either for revision of this standard 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,Uni