1、Designation:A64811 Designation: A648 12Standard Specification forSteel Wire, Hard Drawn for Prestressing Concrete PipeSteelWire, Hard-Drawn for Prestressed Concrete Pipe1This standard is issued under the fixed designation A648; the number immediately following the designation indicates the year ofor
2、iginal adoption or, in the case of revision, the year of last revision. 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-stre
3、ngth, hard-drawn steel wire for use in the manufacture ofprestressed concrete pipe. In application, the wire is helically wrapped on the pipe maintaining tension by mechanical means notincluding drawing dies.1.2 The values stated in inch-pound units are to be regarded as standard. The values given i
4、n parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.1.3Supplementary requirements describe hydrogen embrittlement resistance test acceptance criteria.1.3 A supplementary requirement (S1) is provided for use where hydrogen embri
5、ttlement (HE) resistance testing is required bythe purchaser. Supplementary requirement (S1), which establishes acceptance criteria for HE resistance testing, applies only whenspecified in the purchase order or contract.1.4 The following caveat pertains only to the test method portions of this speci
6、fication, 6.2.3 6.3.3 and 6.4.36.5.3: Thisstandardspecification does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of theuser of this standardspecification to establish appropriate safety and health practices and determine the applicability of
7、regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA510 Specification for General Requirements for Wire Rods and Coarse Round Wire, Carbon SteelA700 Practices for Packaging, Marking, and Loading Meth
8、ods for Steel Products for ShipmentA1032 Test Method for Hydrogen Embrittlement Resistance for Steel Wire Hard Drawn Used for Prestressing Concrete PipeE328 Test Methods for Stress Relaxation for Materials and Structures2.2 ANSI Standard:3C 304 Standard for Design of Prestressed Concrete Cylinder Pi
9、pe3. Ordering Information3.1Orders for material to this specification should include the following information:3.1 It shall be the responsibility of the purchaser to specify all requirements that are necessary for material under thisspecification. Such requirements to be considered include, but are
10、not limited to, the following:3.1.1 Quantity (weight),3.1.2 Name of material (hard-drawn steel wire for prestressingprestressed concrete pipe),3.1.3 Wire diameter (see Table 1),3.1.4 Class (see Table 1),3.1.5Packaging (see Section 113.1.5 If outside inspection is required (9.1),3.1.6ASTM designation
11、 and year of issue, and3.1.7Special requirements, if any (see Supplementary Requirements).1This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.05on Steel Reinforcement.Current edition app
12、roved Jan.March 1, 2011.2012. Published January 2011.April 2012. Originally approved in 1972. Last previous edition approved in 20042011 asA64804a.A648 11. DOI: 10.1520/A0648-112.2For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org
13、. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.1This document is not an ASTM standard and is intend
14、ed only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current
15、 versionof the standard as published by ASTM is to be considered the official document.*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, United States.NOTE1A typical ordering descripti
16、on is as follows: 100000-lb, Hard-Drawn Steel Wire for Prestressing Concrete Pipe, 0.192 in. in diameter, ClassIII, 1500-lb coils, to ASTM A648_.3.1.6 Packaging (see Section 12),3.1.7 Supplementary Requirement S1 (if desired), and3.1.8 ASTM designation and year of issue.4. Manufacture4.1 The steel s
17、hall be made by the electric-arc furnace, open-hearth, basic-oxygen, or basic-oxygen process.4.2 The steel shall be free of injurious piping and undue segregation.4.3 The wire shall be cold drawn to produce the prescribed mechanical properties. The wire manufacturer shall take dependableprecautions
18、during wire drawing to preclude detrimental strain aging of the wire.NOTE 21Allowing wire to remain at elevated temperatures, such as 400F (204C) for more than5sor360F (182C) for more than 20 s, can resultin detrimental strain aging of the wire. Detrimentally strain-aged wire typically has reduced d
19、uctility and increased susceptibility to hydrogenembrittlement.4.4 There shall be no welds or joints in the finished wire. Any welds or joints made during manufacture to enable continuityof operations shall be removed.5. Chemical Requirements5.1 The heat analysis of the steel shall conform to the ch
20、emical requirements specified in Table 2.5.2 An analysis of each heat of steel shall be furnished by the manufacturer showing the percentages of all the elements specifiedin Table 2. The wire shall be subject to permissible variation for product analysis specified in Specification A510, Table 7.6. M
21、echanical Property Requirements Note3Mechanical6.1 Mechanical property requirements are applicable only prior to or during pipe manufacture.TABLE 1 Tensile RequirementsWire Gage orFraction, in.Decimal Size,in. (mm)Class II Wire Class III WireMinimum TensileStrength,Aksi (MPa)Breaking Strength, lbf (
22、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)1/4 0.250 (6.35) 211 (1450) 10 360 (46.1) 11 830 (52.6) 240 (1650) 11 780 (52.4) 13 250 (58.9)5/16 0.312 (7.92) 201 (1390) 15 370 (6
23、8.4) 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 is no requirement orlimit.Classes II and IIICarbon, % 0.500.85Carbon, % 0.500.85Manganese, %
24、0.501.10Manganese, % 0.501.10Phosphorus, max, % 0.030Phosphorus, max, % 0.030Sulfur, max, % 0.035Sulfur, max, % 0.035Silicon, % 0.100.35Silicon, % 0.100.35Nitrogen, max, % 0.007Nitrogen, max, % 0.007Aluminum, %Aluminum, % .Titanium, %Titanium, % .Chromium, %Chromium, % .Nickel, %Nickel, % .Molybdenu
25、m, %Molybdenum, % .Copper, %Copper, % .Vanadium, %Vanadium, % .A648 1226.16.2 Test SpecimensWire specimens for tensile and torsion tests shall be taken from either end of a coil but mustand shallbe representative of that coils wire drawing conditions with regard to wire temperature.6.26.3 Tension Te
26、stsTest:6.2.16.3.1 Tensile RequirementsTensile requirements shall conform to those prescribed in Table 1 for the specified size and class.6.2.26.3.2 Number of TestsOne test specimen shall be taken from each coil.6.2.36.3.3 Test MethodTension tests shall be made in accordance with Test Methods and De
27、finitionsA370,AnnexA4. Tension testreports shall include the coil number tested, the measured wire diameter, and the measured breaking strength.6.2.46.3.4 Reduction-of-Area TestThe reduction of area requirement for the specimens used for the tension test in 6.1 6.2 shall bea minimum of 35 % for 0.19
28、2 in. (4.88 mm) wire and 30 % for larger wire as described and tested in accordance with Test Methodsand Definitions A370, Annex A4.6.36.4 Relaxation Test:6.3.16.4.1 Number of TestsRelaxation test results shall be provided for purposes of qualifying the procedures used to manufacturewire for prestre
29、ssing prestressed concrete pipe. Relaxation test results shall include one specimen from a minimum of three coilsof wire from the same or different heats of steel where the wire specimens are of the same nominal size, the same class, andmanufactured using the same drawing machine and drawing procedu
30、res. It shall be permissible to provide the relaxation test resultsfrom the wire manufacturers historical records.6.3.26.4.2 Test MethodWire shall be tested as described in Test Methods E328.6.3.36.4.3 Conditions of TestsThe conditions of the tests are:6.34.3.1 At least one of the tests performed sh
31、all have a duration of 1000 h minimum, and all other tests shall have a durationof at least 200 h. Measurements shall be made and recorded for at least five data points during each time interval of (1)0to10h, (2) 10 to 100 h, and (3) 100 to 1000 h, except that, if a test is terminated in less than 1
32、000 h, measurements shall be made forat least two data points in the third interval. For tests terminated in less than 1000 h, the expected relaxation of the specimen at1000 h shall be determined from the linear-regression curve of stress loss on a logarithm time scale.6.34.3.2 The temperature of th
33、e test specimen shall be maintained at 68 6 3.5F (20 6 2C).6.34.3.3 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 specimen ends to fit in the testing machine jaws.6.34.3.4 Load
34、ing shall be applied at an essentially constant rate over a period of not less than 3 min and not more than 5 minuntil the initial load is reached. Thereafter, the gage length shall be maintained constant. Load-relaxation readings shall commence1 min after the initial load has been reached.6.34.3.5
35、The initial load shall be 70 % of the specifed minimum breaking strength of the wire. Overstressing of the test specimento a level greater than 70 % of the specified minimum breaking strength during loading shall not be permitted.6.34.3.6 The test gage length shall be at least 60 times the nominal d
36、iameter of the wire.6.34.3.7 The result of each relaxation test shall be reported either as the actual percent of stress loss after 1000 h or theextrapolated percent of stress loss after 1000 h as determined from the linear-regression curve.NOTE4In 2In accordance with ANSI/AWWA C 304, ordinary prest
37、ressed concrete pipe design is based on an assumed maximum wire relaxationof 7.48 % at 1000 h. Wire with higher relaxation can be used, but the higher relaxation loss must be known for consideration in the pipe design.6.46.5 Torsion Test:6.4.16.5.1 Torsion RequirementsTorsion requirements shall conf
38、orm to those prescribed in Table 3 for the specified size and class.6.4.26.5.2 Number of TestsOne test specimen shall be taken from each coil.6.4.36.5.3 Test MethodConduct the torsion test in accordance with the following:TABLE 3 Torsion RequirementsWire Gage orFraction in.Decimal Size,in. (mm)Class
39、 II and Class III minturns per 8 in. (203 mm)6 0.192 (4.88) 101/4 0.250 (6.35) 85/16 0.312 (7.92) 7A648 1236.45.3.1 Use a twist rate of 10 to 30 r/min.6.45.3.2 Load the wire with an axial force of from 0.5 to 2 % of the minimum breaking strength of the wire.6.45.3.3 Use a test specimen length, defin
40、ed as the distance between the testing machine jaws, of a minimum of 8 in. (203 mm).6.45.3.4 Use a minimum number of turns proportional to the length of the test specimen based upon Table 3.6.4.3.56.5.3.5 The test shall be conducted to fracture, defined as complete separation of the broken ends. The
41、 test specimens shall beinspected for primary break shear area and longitudinal (spiral) splitting following completion of the torsion test.(1) Primary Break ShearThe primary break face of the test specimen shall have a clean, flush, full shear face, perpendicularto the wire axis (see Fig. 1).(2) Lo
42、ngitudinal (Spiral) SplittingIf the fractured specimen shows evidence of a spiral split, either visible withoutmagnification (see Fig. 2) or by an offset in the wire surfaces (see Fig. 3) detectable with a fingernail, a retest of that coil shallbe conducted in accordance with 6.4.3.5 6.5.3.5 (3).(3)
43、 Retest for Splitting in Torsion The retest specimen shall have a minimum length of 8 in. (203 mm). The retest shallconsist of twisting the retest specimen proportionally to three twists per 8 in. (203 mm) specimen length, at which point the twistingshall be stopped and the specimen inspected while
44、still in the torsion machine.Aspiral split in this specimen, either visible withoutmagnification or detectable with a fingernail, shall be cause for rejection of the coil.6.45.3.6 The tested coil number, specimen length, and total number of turns shall be recorded.6.56.6 Report of Mechanical Propert
45、y Test Results The wire manufacturer shall furnish a report listing the tensile,reduction-of-area, and torsion test results.7. Dimensions and Permissible Variations7.1 The diameter of the wire shall not vary from that specified by more than 60.002 in. (0.05 mm) in diameter nor more than0.002-in. (0.
46、05-mm) out-of-round.8. Workmanship, Finish, and Appearance8.1 The surface of the wire as received shall be smooth and generally free of rust. A light oxidation film that does not causepitting of the wire surface visible to the unaided eyea person with normal or corrected vision after wiping or light
47、 cleaning, shallnot be cause for rejection. Coils of wire with visible pitting shall be rejected.8.2 The wire shall not have detrimental piping, cross checking, torn surfaces, chatter marks, splits, die marks, scratches, pits,or seams.8.3 The wire shall not be kinked, improperly cast, or show a wavy
48、 condition.8.4 Each coil shall be one continuous length of wire, properly coiled.8.5 The wire shall not be oiled or greased.9. Inspection9.1The manufacturer shall afford the purchasers inspector all reasonable facilities to satisfy him that the material is beingFIG. 1 Acceptable View of the Break Fa
49、ceFIG. 2 Visible Longitudinal (Spiral) Splitting After Torsion TestingFIG. 3 End View of Offset Longitudinal (Spiral) Split After TorsionTestingA648 124produced and furnished in accordance with this specification. All tests and inspections may be made at the place of manufactureprior to shipment and shall be so conducted as not to interfere unnecessarily with the operation of the work.10.9.1 The purchaser shall state at the time of order whether outside inspection is required. If outside inspection is required, themanufacturer shall
