1、Designation: A 490 06American Association StateHighway and TransportationOfficials StandardAASHTO No.: M 253Standard Specification forStructural Bolts, Alloy Steel, Heat Treated, 150 ksi MinimumTensile Strength1This standard is issued under the fixed designation A 490; the number immediately followi
2、ng the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approve
3、d for use by agencies of the Department of Defense.1. Scope*1.1 This specification covers two types of quenched andtempered, alloy steel, heavy hex structural bolts having atensile strength of 150 to 173 ksi.1.2 These bolts are intended for use in structural connec-tions. These connections are cover
4、ed under the requirements ofthe Specification for Structural Joints Using SpecificationA 325 or A 490 bolts, approved by the Research Council onStructural Connections; endorsed by the American Institute ofSteel Construction and by the Industrial Fastener Institute.21.3 The bolts are furnished in siz
5、es12 to 112 in., inclusive.They are designated by type denoting chemical composition asfollows:Type DescriptionType 1 Medium carbon alloy steelType 2 Withdrawn in 2002Type 3 Weathering steel1.4 This specification provides that heavy hex structuralbolts shall be furnished unless other dimensional req
6、uirementsare specified on the purchase order.1.5 Terms used in this specification are defined in Termi-nology F 1789 unless otherwise defined herein.1.6 For metric bolts, see Specification A 490M Classes 10.9and 10.9.31.7 The following safety hazards caveat pertains only to theTest Methods portion,
7、Section 12 of this specification: Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions p
8、rior to use.2. Referenced Documents2.1 ASTM Standards:3A 194/A 194M Specification for Carbon and Alloy SteelNuts for Bolts for High Pressure or High TemperatureService, or BothA 325 Specification for Structural Bolts, Steel, HeatTreated, 120/105 ksi Minimum Tensile StrengthA 354 Specification for Qu
9、enched and Tempered AlloySteel Bolts, Studs, and Other Externally Threaded Fasten-ersA 490M Specification for High-Strength Steel Bolts,Classes 10.9 and 10.9.3, for Structural Steel Joints MetricA 563 Specification for Carbon and Alloy Steel NutsA 751 Test Methods, Practices, and Terminology forChem
10、ical Analysis of Steel ProductsD 3951 Practice for Commercial PackagingE 384 Test Method for Microindentation Hardness of Ma-terialsE 709 Guide for Magnetic Particle ExaminationE 1444 Practice for Magnetic Particle TestingF 436 Specification for Hardened Steel WashersF 606 Test Methods for Determini
11、ng the Mechanical Prop-erties of Externally and Internally Threaded Fasteners,Washers, and RivetsF 788/F 788M Specification for Surface Discontinuities ofBolts, Screws, and Studs, Inch and Metric SeriesF 959 Specification for Compressible-Washer-Type DirectTension Indicators for Use with Structural
12、FastenersF 1470 Guide for Fastener Sampling for Specified Mechani-cal Properties and Performance InspectionF 1789 Terminology for F16 Mechanical FastenersG 101 Guide for Estimating the Atmospheric CorrosionResistance of Low-Alloy Steels1This specification is under the jurisdiction of ASTM Committee
13、F16 onFasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts,Nuts, Rivets, and Washers.Current edition approved Aug. 1, 2006. Published August 2006. Originallyapproved in 1964. Last previous edition approved in 2004 as A 490 04a.2Available from American Institute of Steel C
14、onstruction (AISC), One E.Wacker Dr., Suite 700, Chicago, IL 60601-2001, http:/www.aisc.org.3For 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 S
15、ummary page onthe ASTM website.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, United States.2.2 ASME Standards:4B1.1 Unified Screw ThreadsB18.2.6 Fasteners for Use in Structural Ap
16、plicationsB18.24 Part Identification Number (PIN) Code SystemStandard for B18 Fastener Products2.3 SAE Standard:5SAE J121 Decarburization in Hardened and TemperedThreaded Fasteners3. Ordering Information3.1 Orders for heavy hex structural bolts under this speci-fication shall include the following:3
17、.1.1 Quantity (number of pieces of bolts and accessories);3.1.2 Size, including nominal bolt diameter, thread pitch,and bolt length. The thread length shall not be changed;3.1.3 Name of product: heavy hex structural bolts, or othersuch bolts as specified;3.1.4 Type of bolt (Type 1 or 3). When type i
18、s not specified,either Type 1 or Type 3 shall be furnished at the suppliersoption;3.1.5 ASTM designation and year of issue,3.1.6 Other components such as nuts, washers, and washer-type direct tension indicators, if required;3.1.7 Test Reports, if required (see Section 15); and3.1.8 Special requireme
19、nts.3.1.9 For establishment of a part identifying system, seeASME B18.24.NOTE 1A typical ordering description follows: 1000 pieces 18 in.dia 3 4 in. long heavy hex structural bolt, Type 1, ASTM A 490 02; eachwith two hardened washers, ASTM F 436 Type 1; and one heavy hex nut,ASTM A 563 Grade DH.3.2
20、Recommended Nuts:3.2.1 Nuts conforming to the requirements of SpecificationA 563 are the recommended nuts for use with SpecificationA 490 heavy hex structural bolts. The nuts shall be of the classand have a surface finish for each type of bolt as follows:Bolt Type and Finish Nut Class and Finish1, p
21、lain (uncoated) A 563DH, DH3 plain (uncoated)3, weathering steel A 563DH3, weathering steel3.2.2 Alternatively, nuts conforming to Specification A 194/A 194M Gr. 2H plain (uncoated) are considered a suitablesubstitute for use with Specification A 490 Type 1 heavy hexstructural bolts.3.3 Recommended
22、WashersWashers conforming to Speci-fication F 436 are the recommended washers for use withSpecification A 490 heavy hex structural bolts. The washersshall have a surface finish for each type of bolt as follows:Bolt Type and Finish Washer Finish1, plain (uncoated) plain (uncoated)3, weathering steel
23、weathering steel3.4 Other AccessoriesWhen compressible washer typedirect tension indicators are specified to be used with thesebolts, they shall conform to Specification F 959 Type 490.4. Materials and Manufacture4.1 Heat TreatmentType 1 and Type 3 bolts shall be heattreated by quenching in oil from
24、 the austenitic temperature andthen tempered by reheating to a temperature of not less than800F.4.2 ThreadingThe threads shall be cut or rolled.4.3 Protective CoatingsThe bolts shall not be coated byhot-dip zinc coating, mechanical deposition, or electroplatingwith zinc or other metallic coatings (N
25、ote 2).NOTE 2For more detail see the H. E. Townsend Report “Effects ofZinc Coatings on Stress Corrosion Cracking and Hydrogen Embrittlementof LowAlloy Steel,” published in Metallurgical Transactions, Vol. 6,April1975.5. Chemical Composition5.1 Type 1 bolts shall be alloy steel conforming to thechemi
26、cal composition specified in Table 1. The steel shallcontain sufficient alloying elements to qualify it as an alloysteel (see Note 3).NOTE 3Steel is considered to be alloy by the American Iron and SteelInstitute when the maximum of the range given for the content of alloyingelements exceeds one or m
27、ore of the following limits: manganese, 1.65 %;silicon, 0.60 %; copper, 0.60 %; or in which a definite range or a definiteminimum quantity of any of the following elements is specified orrequired within the limits of the recognized field of constructional alloysteels: aluminum, chromium up to 3.99 %
28、, cobalt, columbium, molybde-num, nickel, titanium, tungsten, vanadium, zirconium, or any otheralloying elements added to obtain a desired alloying effect.5.2 Type 3 bolts shall be weathering steel conforming to thechemical composition requirements in Table 2. See GuideG 101 for methods of estimatin
29、g the atmospheric corrosionresistance of low alloy steel.5.3 Product analyses made on finished bolts representingeach lot shall conform to the product analysis requirementsspecified in Tables 1 and 2, as applicable.5.4 Heats of steel to which bismuth, selenium, tellurium, orlead has been intentional
30、ly added shall not be used for boltsfurnished to this specification. Compliance with this require-ment shall be based on certification that steels having theseelements intentionally added were not used.5.5 Chemical analyses shall be performed in accordancewith Test Methods, Practices, and Terminolog
31、y A 751.6. Mechanical Properties6.1 HardnessThe bolts shall conform to the hardnessspecified in Table 3.4Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.5Available from Society of Automotive
32、Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.TABLE 1 Chemical Requirements for Type 1 BoltsElement Heat Analysis, % ProductAnalysis, %CarbonFor sizes through 138 in. 0.300.48 0.280.50For size 112 in. 0.350.53 0.330.55Phosphorus, max 0.040 0.045Sulfur, max 0.040
33、0.045Alloying Elements See 5.1 A 4900626.2 Tensile Properties:6.2.1 Except as permitted in 6.2.2 for long bolts and 6.2.3for short bolts, sizes 1.00 in. and smaller having a length of 214D and longer and sizes larger than 1.00 in. having a length of3D and longer shall be wedge tested full size and s
34、hall conformto the minimum and maximum wedge tensile load, and proofload or alternative proof load specified in Table 4. The loadachieved during proof load testing shall be equal to or greaterthan the specified proof load.6.2.2 When the length of the bolt makes full-size testingimpractical, machined
35、 specimens shall be tested and shallconform to the requirements specified in Table 5. When boltsare tested by both full-size and machined specimen methods,the full-size test shall take precedence.6.2.3 Sizes 1.00 in. and smaller having a length shorter than214 D down to 2D, inclusive, that cannot be
36、 wedge tensiletested shall be axially tension tested full size and shall conformto the minimum tensile load and proof load or alternate proofload specified in Table 4. Sizes 1.00 in. and smaller having alength shorter than 2D that cannot be axially tensile tested shallbe qualified on the basis of ha
37、rdness.6.2.4 For bolts on which hardness and tension tests areperformed, acceptance based on tensile requirements shall takeprecedence in the event of low hardness readings.7. Carburization/Decarburization7.1 This test is intended to evaluate the presence or absenceof carburization and decarburizati
38、on as determined by thedifference in microhardness near the surface and core.7.2 Requirements:7.2.1 CarburizationThe bolts shall show no evidence of acarburized surface when evaluated in accordance with 12.2.7.2.2 DecarburizationHardness value differences shallnot exceed the requirements set forth f
39、or decarburization inSAE J121 for Class 2/3H materials when evaluated in accor-dance with 12.2.8. Dimensions8.1 Head and Body:8.1.1 Unless otherwise specified, bolts shall conform to thedimensions for heavy hex structural bolts specified in ASMEB18.2.6.8.1.2 The thread length shall not be changed fr
40、om thatspecified in ASME B18.2.6 for heavy hex structural bolts.Bolts requiring thread lengths other than those required by thisspecification shall be ordered under Specification A 354 Gr.BD.8.2 ThreadsThreads shall be the Unified Coarse ThreadSeries as specified in ASME B1.1 and shall have Class 2A
41、tolerances.9. Workmanship9.1 The allowable limits, inspection, and evaluation of thesurface discontinuities, quench cracks, forging cracks, headbursts, shear bursts, seams, folds, thread laps, voids, toolmarks, nicks, and gouges shall be in accordance with Specifi-cation F 788/F 788M (see Note 4).NO
42、TE 4Specification F 788/F 788M nor Guide F 1470 do not guar-antee 100 % freedom from head bursts. Sampling is designed to providea 95 % confidence level of freedom from head bursts in any test lot. Headbursts, within the limits in Specification F 788/F 788M, are unsightly butdo not affect mechanical
43、 properties or functional requirements of the bolt.10. Magnetic Particle Inspection for LongitudinalDiscontinuities and Transverse Cracks10.1 Requirements:10.1.1 Each sample representative of the lot shall be mag-netic particle inspected for longitudinal discontinuities andtransverse cracks.10.1.2 T
44、he lot, as represented by the sample, shall be freefrom nonconforming bolts, as defined in 10.3, when inspectedin accordance with 10.2.1-10.2.4.10.2 Inspection Procedure:10.2.1 The inspection sample shall be selected at randomfrom each lot in accordance with Table 6 and examined forlongitudinal disc
45、ontinuities and transverse cracks.10.2.2 Magnetic particle inspection shall be conducted inaccordance with Guide E 709 or Practice E 1444. Guide E 709shall be used for referee purposes. If any nonconforming boltis found during the manufacturers examination of the lotselected in 10.2.1, the lot shall
46、 be 100 % magnetic particleinspected, and all nonconforming bolts shall be removed andscrapped or destroyed.10.2.3 Eddy current or liquid penetrant inspection shall bean acceptable substitute for the 100 % magnetic particleinspection when nonconforming bolts are found and 100 %inspection is required
47、. On completion of the eddy current orliquid penetrant inspection, a random sample selected fromeach lot in accordance with Table 5 shall be re-examined by themagnetic particle method. In case of controversy, the magneticparticle test shall take precedence.10.2.4 Magnetic particle indications of the
48、mselves shall notbe cause for rejection. If in the opinion of the quality assurancerepresentative the indications may be cause for rejection, asample taken in accordance with Table 5 shall be examined bymicroscopic examination or removal by surface grinding todetermine if the indicated discontinuiti
49、es are within the speci-fied limits.10.3 Definitions:10.3.1 Nonconforming BoltsAny bolt with a longitudinaldiscontinuity (located parallel to the axis of the bolt in thethreads, body, fillet, or underside of head), with a depth normalto the surface greater than 0.03D, where D is the nominalTABLE 2 Chemical Requirements for Type 3 BoltsElement Heat Analysis, % Product Analysis, %CarbonSizes 0.75 in. and smaller 0.200.53 0.190.55Sizes larger than 0.75 in. 0.300.53 0.280.55Manganese, min 0.40 0.37Phosphorus, max 0.035 0.040Sulfur, max 0.040 0.0
