1、Designation: A648 18Standard Specification forSteel Wire, Hard-Drawn for Prestressed Concrete Pipe1This standard is issued under the fixed designation A648; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 specification covers two classes of uncoated, high-strength, hard-drawn steel wire for use in the manufacture ofprestressed co
3、ncrete pipe. In application, the wire is helicallywrapped on the pipe maintaining tension by mechanical meansnot including drawing dies.1.2 A supplementary requirement (S1) is provided for usewhere hydrogen embrittlement (HE) resistance testing is re-quired by the purchaser. Supplementary requiremen
4、t (S1),which establishes acceptance criteria for HE resistance testing,applies only when specified in the purchase order or contract.1.3 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
5、information onlyand are not considered standard.1.4 The following caveat pertains only to the test methodportions of this specification, 6.3.3 and 6.5.3: This standarddoes not purport to address all of the safety concerns, if any,associated with its use. It is the responsibility of the user of thiss
6、tandard to establish appropriate safety, health, and environ-mental practices and determine the applicability of regulatorylimitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision
7、on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA510 Specific
8、ation for General Requirements for Wire Rodsand Coarse Round Wire, Carbon SteelA700 Guide for Packaging, Marking, and Loading Methodsfor Steel Products for ShipmentA941 Terminology Relating to Steel, Stainless Steel, RelatedAlloys, and FerroalloysA1032 Test Method for Hydrogen Embrittlement Resistan
9、cefor Steel Wire Hard-Drawn Used for Prestressed ConcretePipeE328 Test Methods for Stress Relaxation for Materials andStructures2.2 ANSI Standard:3C 304 Standard for Design of Prestressed Concrete CylinderPipe3. Terminology3.1 Definitions:3.1.1 For definition of terms used in this specification, ref
10、erto Terminology A941.4. Ordering Information4.1 Orders for hard-drawn steel wire under this specificationshall contain the following information:4.1.1 Quantity (weight),4.1.2 Name of material (hard-drawn steel wire for pre-stressed concrete pipe),4.1.3 Wire diameter (see Table 1),4.1.4 Class (Table
11、 1), and4.1.5 ASTM designation and year of issue.4.2 The purchaser shall have the option to specify additionalrequirements, including but not limited to, the following:4.2.1 Requirements for inspection (9.1),4.2.2 Special package marking requirements (Section 12),4.2.3 Supplementary Requirement S1,
12、and4.2.4 Other special requirements, if any.5. Manufacture and Chemical Requirements5.1 The steel shall be made by any commercially acceptedprocess.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of Subc
13、ommitteeA01.05 on Steel Reinforcement.Current edition approved March 1, 2018. Published March 2018. Originallyapproved in 1972. Last previous edition approved in 2012 as A648 12. DOI:10.1520/A0648-18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Servic
14、e 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 appe
15、ars at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Princip
16、les for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15.2 The steel shall be free of injurious piping and unduesegregation.5.3 The wire shall be cold drawn to produce the prescribedmechanical
17、properties. The wire manufacturer shall take de-pendable precautions during wire drawing to preclude detri-mental strain aging of the wire.NOTE 1Allowing wire to remain at elevated temperatures, such as400F (204C) for more than5sor360F (182C) for more than 20 s, canresult in detrimental strain aging
18、 of the wire. Detrimentally strain-agedwire typically has reduced ductility and increased susceptibility tohydrogen embrittlement.5.4 There shall be no welds or joints in the finished wire.Any welds or joints made during manufacture to enablecontinuity of operations shall be removed.5.5 Chemical Req
19、uirements:5.5.1 The heat analysis of the steel shall conform to thechemical requirements specified in Table 2.5.5.2 An analysis of each heat of steel shall be furnished bythe manufacturer showing the percentages of all the elementsspecified in Table 2. The wire shall be subject to permissiblevariati
20、on for product analysis specified in Specification A510,Table 7.6. Mechanical Property Requirements6.1 Mechanical property requirements are applicable onlyprior to or during pipe manufacture.6.2 Test SpecimensIt shall be permissible to take wirespecimens for tensile and torsion tests from either end
21、 of a coil.Wire test specimens shall be representative of that coils wiredrawing conditions with regard to wire temperature.6.3 Tension Test:6.3.1 Tensile RequirementsTensile requirements shallconform to those prescribed in Table 1 for the specified sizeand class.6.3.2 Number of TestsOne test specim
22、en shall be takenfrom each coil.6.3.3 Test MethodTension tests shall be made in accor-dance with Test Methods and Definitions A370, Annex A4.Tension test reports shall include the coil number tested, themeasured wire diameter, and the measured breaking strength.6.3.4 Reduction-of-Area TestThe reduct
23、ion of area re-quirement for the specimens used for the tension test in 6.2shall be a minimum of 35 % for 0.192 in. (4.88 mm) wire and30 % for larger wire as described and tested in accordance withTest Methods and Definitions A370, Annex A4.6.4 Relaxation Test:6.4.1 Number of TestsRelaxation test re
24、sults shall beprovided for purposes of qualifying the procedures used tomanufacture wire for prestressed concrete pipe. Relaxation testresults shall include one specimen from a minimum of threecoils of wire from the same or different heats of steel where thewire specimens are of the same nominal siz
25、e, the same class,and manufactured using the same drawing machine and draw-ing procedures. It shall be permissible to provide the relaxationtest results from the wire manufacturers historical records.6.4.2 Test MethodWire shall be tested as described in TestMethods E328.6.4.3 Conditions of TestsThe
26、conditions of the tests are:6.4.3.1 At least one of the tests performed shall have aduration of 1000 h minimum, and all other tests shall have aduration of at least 200 h. Measurements shall be made andrecorded for at least five data points during each time intervalof (1)0to10h,(2) 10 to 100 h, and
27、(3) 100 to 1000 h, exceptthat, if a test is terminated in less than 1000 h, measurementsshall be made for at least two data points in the third interval.For tests terminated in less than 1000 h, the expected relaxationof the specimen at 1000 h shall be determined from thelinear-regression curve of s
28、tress loss on a logarithm time scale.6.4.3.2 The temperature of the test specimen shall bemaintained at 68 6 3.5F (20 6 2C).6.4.3.3 The test specimen shall not be subjected to loading,including specimen straightening, prior to the relaxation test,except that it shall be permissible to straighten the
29、 specimenends to fit in the testing machine jaws.6.4.3.4 Loading shall be applied at an essentially constantrate over a period of not less than 3 min and not more than 5min until the initial load is reached. Thereafter, the gage lengthTABLE 1 Tensile RequirementsWire Gage orFraction, in.Decimal Size
30、,in. (mm)Class II Wire Class III WireMinimum TensileStrength,Aksi (MPa)Breaking Strength, lbf (kN) Minimum TensileStrength,Aksi (MPa)Breaking Strength, lbf (kN)min max min max6 0.192 (4.88) 222 (1530) 6 430 (28.6) 7 300 (32.5) 252 (1740) 7 300 (32.5) 8 170 (36.3)14 0.250 (6.35) 211 (1450) 10 360 (46
31、.1) 11 830 (52.6) 240 (1650) 11 780 (52.4) 13 250 (58.9)516 0.312 (7.92) 201 (1390) 15 370 (68.4) 17 660 (78.6) 221 (1520) 16 900 (75.2) 19 190 (85.4)ABased on nominal wire diameter.TABLE 2 Chemical RequirementsNOTE 1Class I wire has been discontinued.NOTE 2Where “. . .” appear in this table, there
32、is no requirement orlimit.Classes II and IIICarbon, % 0.500.85Manganese, % 0.501.10Phosphorus, max, % 0.030Sulfur, max, % 0.035Silicon, % 0.100.35Nitrogen, max, % 0.007Aluminum, % . . .Titanium, % . . .Chromium, % . . .Nickel, % . . .Molybdenum, % . . .Copper, % . . .Vanadium, % . . .A648 182shall b
33、e maintained constant. Load-relaxation readings shallcommence 1 min after the initial load has been reached.6.4.3.5 The initial load shall be 70 % of the specifiedminimum breaking strength of the wire. Overstressing of thetest specimen to a level greater than 70 % of the specifiedminimum breaking st
34、rength during loading shall not be per-mitted.6.4.3.6 The test gage length shall be at least 60 times thenominal diameter of the wire.6.4.3.7 The result of each relaxation test shall be reportedeither as the actual percent of stress loss after 1000 h or theextrapolated percent of stress loss after 1
35、000 h as determinedfrom the linear-regression curve.NOTE 2In accordance with ANSI/AWWA C 304, ordinary prestressedconcrete pipe design is based on an assumed maximum wire relaxation of7.48 % at 1000 h. Wire with higher relaxation can be used, but the higherrelaxation loss must be known for considera
36、tion in the pipe design.6.5 Torsion Test:6.5.1 Torsion RequirementsTorsion requirements shallconform to those prescribed in Table 3 for the specified sizeand class.6.5.2 Number of TestsOne test specimen shall be takenfrom each coil.6.5.3 Test MethodConduct the torsion test in accordancewith the foll
37、owing:6.5.3.1 Use a twist rate of 10 to 30 r/min.6.5.3.2 Load the wire with an axial force of from 0.5 to 2 %of the minimum breaking strength of the wire.6.5.3.3 Use a test specimen length, defined as the distancebetween the testing machine jaws, of a minimum of 8 in. (203mm).6.5.3.4 Use a minimum n
38、umber of turns proportional to thelength of the test specimen based upon Table 3.6.5.3.5 The test shall be conducted to fracture, defined ascomplete separation of the broken ends. The test specimensshall be inspected for primary break shear area and longitudinal(spiral) splitting following completio
39、n of the torsion test.(1) Primary Break ShearThe primary break face of thetest specimen shall have a clean, flush, full shear face,perpendicular to the wire axis (see Fig. 1).(2) Longitudinal (Spiral) SplittingIf the fractured speci-men shows evidence of a spiral split, either visible withoutmagnifi
40、cation (see Fig. 2) or by an offset in the wire surfaces(see Fig. 3) detectable with a fingernail, a retest of that coilshall be conducted in accordance with 6.5.3.5 (3).(3) Retest for Splitting in TorsionThe retest specimenshall have a minimum length of 8 in. (203 mm). The retest shallconsist of tw
41、isting the retest specimen proportionally to threetwists per 8 in. (203 mm) specimen length, at which point thetwisting shall be stopped and the specimen inspected while stillin the torsion machine. A spiral split in this specimen, eithervisible without magnification or detectable with a fingernail,
42、shall be cause for rejection of the coil.6.5.3.6 The tested coil number, specimen length, and totalnumber of turns shall be recorded.6.6 Report of Mechanical Property Test ResultsThe wiremanufacturer shall furnish a report listing the tensile,reduction-of-area, and torsion test results.7. Dimensions
43、 and Permissible Variations7.1 The diameter of the wire shall not vary from thatspecified by more than 60.002 in. (0.05 mm) in diameter normore than 0.002-in. (0.05-mm) out-of-round.8. Workmanship, Finish, and Appearance8.1 The surface of the wire as received shall be smooth andgenerally free of rus
44、t.Alight oxidation film that does not causepitting of the wire surface visible to a person with normal orcorrected vision after wiping or light cleaning, shall not because for rejection. Coils of wire with visible pitting shall berejected.8.2 The wire shall not have detrimental piping, crosschecking
45、, torn surfaces, chatter marks, splits, die marks,scratches, pits, or seams.8.3 The wire shall not be kinked, improperly cast, or showa wavy condition.8.4 Each coil shall be one continuous length of wire,properly coiled.8.5 The wire shall not be oiled or greased.TABLE 3 Torsion RequirementsWire Gage
46、 orFraction in.Decimal Size,in. (mm)Class II and Class III minturns per 8 in. (203 mm)6 0.192 (4.88) 1014 0.250 (6.35) 8516 0.312 (7.92) 7FIG. 1 Acceptable View of the Break FaceFIG. 2 Visible Longitudinal (Spiral) Splitting After Torsion TestingFIG. 3 End View of Offset Longitudinal (Spiral) Split
47、After Tor-sion TestingA648 1839. Inspection9.1 Inspection of the hard-drawn steel wire shall be agreedupon between the purchaser and the manufacturer as part of thepurchase order or contract.10. Certification10.1 At the time of shipment, the purchaser shall befurnished with a written certification t
48、hat specimens represent-ing each lot have been either tested or inspected as required inthis specification and the requirements have been satisfied. Thecertification shall include ASTM designation A648, year ofissue, and revision letter, if any.10.2 A material test report, certificate of inspection,
49、 orsimilar document printed from or used in electronic form froman electronic data interchange (EDI) transmission shall beregarded as having the same validity as a counterpart printed inthe certifiers facility. The content of the EDI transmitteddocument shall meet the requirements of the invoked ASTMstandard(s) and conform to any existing EDI agreement be-tween the purchaser and the manufacturer. Notwithstanding theabsence of a signature, the organization submitting the EDItransmission is responsible for the content of the report.NOTE 3The indu
