ASTM A898 A898M-2007(2012) Standard Specification for Straight Beam Ultrasonic Examination of Rolled Steel Structural Shapes 《轧制结构钢型材的直束超声检验标准规范》.pdf

1、Designation: A898/A898M 07 (Reapproved 2012)Standard Specification forStraight Beam Ultrasonic Examination of Rolled SteelStructural Shapes1This standard is issued under the fixed designation A898/A898M; the number immediately following the designation indicates the yearof original adoption or, in t

2、he case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the procedure and acceptancestandards for straight beam, pu

3、lse echo, ultrasonic examinationof rolled structural shapes having a minimum section thicknessof12 in. 12.5 mm. It was developed to ensure delivery of steelstructural shapes free of gross internal discontinuities such aspipe, ruptures, or laminations and is to be used whenever theinquiry, contract,

4、order, or specification states that the shapesare to be ultrasonically examined. Two levels of acceptancestandards are included. Level II is intended for normal appli-cations where freedom from gross internal discontinuities isdesired, particularly in connection regions. Level I is intendedfor criti

5、cal applications such as welded chord members used intension loading, where internal discontinuities could be detri-mental. Level II is normally applicable unless otherwisespecified in contract documents or the purchase order. Supple-mentary requirements for alternative scanning coverages areprovide

6、d.1.2 The values stated in either inch-pound or SI units are tobe regarded separately as standard. Within the text, the SI unitsare shown in brackets. The values stated in each system are notexact equivalents; therefore, each system must be used inde-pendently of the other. Combining values from the

7、 two systemsmay result in nonconformance with the specification.2. Referenced Documents2.1 ASTM Standards:2A6/A6M Specification for General Requirements for RolledStructural Steel Bars, Plates, Shapes, and Sheet PilingE317 Practice for Evaluating Performance Characteristicsof Ultrasonic Pulse-Echo T

8、esting Instruments and Systemswithout the Use of Electronic Measurement Instruments2.2 ASNT Standard:3SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing33. Ordering Information3.1 The inquiry and order should indicate the following:3.1.1 Acceptanc

9、e level requirements will be Level II unlessotherwise specified.3.1.2 Any additions to the provisions of this specification asoutlined in 8.3.3.1.3 Supplementary requirements, if any.4. Apparatus4.1 The manufacturer shall furnish suitable ultrasonicequipment and qualified personnel necessary for per

10、formingthe examination. The equipment shall be straight beam, pulse-echo and span a nominal test frequency range of 1 to 5 MHz.The search unit shall be within the range of12 in. 12.5 mm to118 in. 30 mm in diameter or12 12.5 mm to 1 in. 25 mmsquare (including the pitch-catch type probe). The test sha

11、ll beperformed by one of the following methods: contact, immer-sion, or liquid column coupling.4.2 Other search units may be used for evaluating andpin-pointing indications.5. Personnel Qualification5.1 Individuals performing examinations in accordance withthis specification shall be qualified and c

12、ertified in accordancewith the requirements of the latest edition of ASNT SNT-TC-1A or an equivalent accepted standard. An equivalentstandard is one that covers the qualification and certification ofultrasonic nondestructive examination candidates, and that isacceptable to the purchaser.6. Test Cond

13、itions6.1 Conduct the examination in an area free of operationsthat interfere with proper functioning of equipment and testingpersonnel.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.

14、02 on Structural Steel for Bridges, Buildings, Rolling Stock and Ships.Current edition approved March 1, 2012. Published April 2012. Originallyapproved in 1990. Last previous edition approved in 2007 as A898/A898M 07.DOI: 10.1520/A0898_A0898M-07R12.2For referenced ASTM standards, visit the ASTM webs

15、ite, 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 website.3Available fromAmerican Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus,

16、OH 43228-0518, http:/www.asnt.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 The section surfaces shall be sufficiently clean andsmooth to maintain a back reflection from the opposite side ofthe flanges, legs, and webs appro

17、ximately comparable to theheight observed at the scanning gain level obtained in 8.2.6.3 The surfaces of the shapes inspected by this method maybe expected to contain a residue of oil or rust or both. Anyspecified identification that is removed when grinding as aresult of surface preparation or exam

18、ination shall be restored.7. Calibration7.1 Standards having14 in. 6 mm diameter flat bottomedholes are used for calibration. The metal distance between thehole bottom and sound entry surface in relation to sectionthickness is given in Table 1.7.2 Standards shall be obtained from a rolled structural

19、shape or plate having surface conditions and acoustic proper-ties similar to that of the product being inspected.8. Test Method8.1 Ultrasonic examination shall be made on the majorsurface of each flange and one major web surface. Evaluationof indications may require inspection from an opposite surfa

20、ce.8.2 The reference level sensitivity shall be established byadjusting the maximum response obtained from the flat-bottomed hole between 50 and 80 % of full screen scale. Whenscanning, the gain level shall be increased to at least twice thereference level sensitivity as measured on the cathode ray

21、tube(CRT) (typically 6 dB).All indications shall be evaluated at thereference level sensitivity.8.2.1 When scanning the flanges or legs above the web, thecalibrated range control (sweep) of the instrument should be setso there is adequate display range for indications that may liebetween fillets, at

22、 a depth greater than the flange or legthickness.8.3 A nominal frequency between 1 and 5 MHz is recom-mended for examination. Thickness, grain size, or microstruc-ture of the material and nature of the equipment or method mayrequire a different test frequency. However, frequencies lessthan 1 MHz may

23、 be used only by agreement with thepurchaser. A clear, easily interpreted trace pattern should beproduced during the examination.8.4 Scanning Coverage:8.4.1 Scanning coverage of the web and flange is illustratedin Fig. 1. A 6-in. wide 150 mm lateral strip with a 10 %overlap between each scan path sh

24、all be scanned at each end,and a zig-zag scan shall be utilized over the length of theremaining flanges and web areas.8.4.2 When an indication of concern (reference level) isdetected along a given scan line in Fig. 1, the flange or webshall be continuously scanned (100 %) with not less than 10 %over

25、lap between each scan path for 9 in. 230 mm adjacent tothe scan line in both directions.8.4.3 All indications shall be evaluated on the flat-bottomedhole reference level criteria, and not by loss of back reflection.8.5 A suitable couplant such as water, water soluble oil, oil,or glycerin, shall be u

26、sed when the contact method is utilized.9. Acceptance Standards9.1 Any discontinuity indication that equals or exceeds thereference level response from the flat-bottomed hole shall beevaluated. A reference level indication that exceeds any of thefollowing criteria is cause for material rejection.9.2

27、 Level I:9.2.1 Flanges or LegsAny reference level indication thatis continuous for a distance of 3 in. 75 mm or greater in anydirection is cause for rejection. Any reference level indicationless than 3 in. 75 mm long must be separated from anotherreference level indication by one-half the flange or

28、leg thick-ness or 2 in. 50 mm, whichever is greater, or the twoindications must be contained within a 3-in. 75 mm diametercircle for acceptance.NOTE 1A loss of back reflection over the web will be experiencedduring the flange scan and is not a cause for rejection.9.2.2 WebAny reference level indicat

29、ion that is continu-ous for a distance of 4 in. 100 mm or greater in any directionis cause for rejection. Any reference level indication less than4 in. 100 mm long must be separated from another referencelevel indication by one-half the web thickness or 2 in. 50 mm,whichever is greater, or the two i

30、ndications must be containedwithin a 4-in. 100 mm diameter circle for acceptance.9.3 Acceptance StandardsLevel II, Flanges, Legs, andWebAny reference level indication shall be rejectable if it iscontinuous for a distance of more than 15 in. 375 mm in anydirection or its area exceeds 7 in.24375 mm2.N

31、OTE 2A loss of back reflection over the web will be experiencedduring the flange scan and is not a cause for rejection.10. Rejection and Rehearing10.1 The manufacturer reserves the right to discuss reject-able ultrasonically tested structural shapes with the purchaserwith the object of possible repa

32、ir of the ultrasonically indicatedimperfection in lieu of rejection of the shape.TABLE 1 Relationship of Distance and ThicknessSection Thickness, T, (in.) Metal Distance, in. mm12 to 112 in. 12.5 mmOver 1 to 11212 to34 TOver 112 to 2 1 in. 25 mmOver 212 to34 TFIG. 1 Scanning Pattern and CoverageA898

33、/A898M 07 (2012)211. Product Marking11.1 Structural shapes accepted in accordance with thisspecification shall be marked UT-A-898-1 for Level I orUT-A-898-2 for Level II, adjacent to marking required by thematerial specification.12. Keywords12.1 acceptance standards; internal discontinuities; proce-

34、dure; pulse echo; rolled; shapes; steel; straight beam; structuralsteel; ultrasonic examinationSUPPLEMENTARY REQUIREMENTSThese supplementary requirements shall apply only when individually specified by the purchaser.When details of these requirements are not covered herein, they are subject to agree

35、ment between themanufacturer and purchaser.S1. Scanning Designated Additional AreasS1.1 In addition to the scanning specified in 8.4, scanning ofadditional areas or different scanning patterns may be specifiedby agreement between the manufacturer and purchaser.S1.2 Acceptance Level II shall apply un

36、less otherwiseagreed to between the manufacturer and purchaser.S2. Scanning 100 %S2.1 Scanning shall be continuous over 100 % with a 10 %overlap between each scan path of both flange or leg surfacesand one major web surface.S2.2 The acceptance criteria for Level I shall apply.S3. Restrictive Accepta

37、nce and Scanning CriteriaS3.1 More stringent acceptance and scanning criteria mayapply upon agreement between the purchaser andmanufacturer.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this

38、standard are expressly advised that determination of the validity 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

39、 andif not revised, either reapproved or withdrawn. Your comments 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 committe

40、e, 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-

41、2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).A898/A898M 07 (2012)3