1、Designation: A 435/A 435M 90 (Reapproved 2007)Standard Specification forStraight-Beam Ultrasonic Examination of Steel Plates1This standard is issued under the fixed designation A 435/A 435M; the number immediately following the designation indicates the yearof original adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification2covers the procedure and acceptancestandards for straight-beam, pulse-echo, ul
3、trasonic examina-tion of rolled fully killed carbon and alloy steel plates,12 in.12.5 mm and over in thickness. It was developed to assuredelivery of steel plates free of gross internal discontinuitiessuch as pipe, ruptures, or laminations and is to be usedwhenever the inquiry, contract, order, or s
4、pecification statesthat the plates are to be subjected to ultrasonic examination.1.2 Individuals performing examinations in accordance withthis specification shall be qualified and certified in accordancewith the requirements of the latest edition of ASNT SNT-TC-1A or an equivalent accepted standard
5、. An equivalentstandard is one which covers the qualification and certificationof ultrasonic nondestructive examination candidates and whichis acceptable to the purchaser.1.3 The values stated in either inch-pound units or SI unitsare to be regarded separately as standard. Within the text, theSI uni
6、ts are shown in brackets. The values stated in eachsystem are not exact equivalents, therefore, each system mustbe used independently of the other. Combining values from thetwo systems may result in nonconformance with the specifi-cation.2. Referenced Documents2.1 ASNT Documents:3ASNT SNT-TC-1A Reco
7、mmended Practice for PersonnelQualification and Certification in Nondestructive Testing3. Apparatus3.1 The manufacturer shall furnish suitable ultrasonicequipment and qualified personnel necessary for performingthe test. The equipment shall be of the pulse-echo straight beamtype. The transducer is n
8、ormally 1 to 118 in. 25 to 30 mm indiameter or 1 in. 25 mm square; however, any transducerhaving a minimum active area of 0.7 in.2450 mm2 may beused. The test shall be performed by one of the followingmethods: direct contact, immersion, or liquid column coupling.3.2 Other search units may be used fo
9、r evaluating andpinpointing indications.4. Test Conditions4.1 Conduct the examination in an area free of operationsthat interfere with proper functioning of the equipment.4.2 Clean and smooth the plate surface sufficiently tomaintain a reference back reflection from the opposite side ofthe plate at
10、least 50 % of the full scale during scanning.4.3 The surface of plates inspected by this method may beexpected to contain a residue of oil or rust or both. Anyspecified identification which is removed when grinding toachieve proper surface smoothness shall be restored.5. Procedure5.1 Ultrasonic exam
11、ination shall be made on either majorsurface of the plate. Acceptance of defects in close proximitymay require inspection from the second major surface. Platesordered in the quenched and tempered condition shall be testedfollowing heat treatment.5.2 A nominal test frequency of 214 MHz is recommended
12、.Thickness, grain size, or microstructure of the material andnature of the equipment or method may require a higher orlower test frequency. However, frequencies less than 1 MHzmay be used only on agreement with the purchaser. A clear,easily interpreted trace pattern should be produced during theexam
13、ination.5.3 Conduct the examination with a test frequency andinstrument adjustment that will produce a minimum 50 to amaximum 75 % of full scale reference back reflection from theopposite side of a sound area of the plate. While calibrating theinstrument, sweep the crystal along the plate surface fo
14、r adistance of at least 1T or 6 in. 150 mm, whichever is thegreater, and note the position of the back reflection. A shift inlocation of the back reflection during calibration shall be causefor recalibration of the instrument.1This specification is under the jurisdiction of ASTM Committee A01 on Ste
15、el,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.11 on Steel Plates for Boilers and Pressure Vessels.Current edition approved March 1, 2007. Published March 2007. Originallyapproved in 1959. Last previous edition approved in 2001 as A 435/A 435M 90 (2001).2Fo
16、r ASME Boiler and Pressure Vessel Code applications, see related Specifi-cations SA-435/SA-435M in Section II of that Code. Available from AmericanSociety of Mechanical Engineers (ASME), ASME International Headquarters,Three Park Ave., New York, NY 10016-5990, http:/www.asme.org.3Available fromAmeri
17、can Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.4 Scanning shall be continuous along perpendicular gridli
18、nes on nominal 9-in. 225-mm centers, or at the manufac-turers option, shall be continuous along parallel paths, trans-verse to the major plate axis, on nominal 4-in. 100-mmcenters, or shall be continuous along parallel paths parallel tothe major plate axis, on 3-in. 75-mm or smaller centers. Asuitab
19、le couplant such as water, soluble oil, or glycerin, shallbe used.5.5 Scanning lines shall be measured from the center or onecorner of the plate. An additional path shall be scanned within2 in. 50 mm of all edges of the plate on the scanning surface.5.6 Where grid scanning is performed and complete
20、loss ofback reflection accompanied by continuous indications isdetected along a given grid line, the entire surface area of thesquares adjacent to this indication shall be scanned continu-ously. Where parallel path scanning is performed and completeloss of back reflection accompanied by continuous i
21、ndicationsis detected, the entire surface area ofa9by9-in. 225 by225-mm square centered on this indication shall be scannedcontinuously. The true boundaries where this condition existsshall be established in either method by the following tech-nique: Move the transducer away from the center of thedi
22、scontinuity until the heights of the back reflection anddiscontinuity indications are equal. Mark the plate at a pointequivalent to the center of the transducer. Repeat the operationto establish the boundary.6. Acceptance Standards6.1 Any discontinuity indication causing a total loss of backreflecti
23、on which cannot be contained within a circle, thediameter of which is 3 in. 75 mm or one half of the platethickness, whichever is greater, is unacceptable.6.2 The manufacturer reserves the right to discuss rejectableultrasonically tested plates with the purchaser with the objectof possible repair of
24、 the ultrasonically indicated defect beforerejection of the plate.6.3 The purchasers representative may witness the test.7. Marking7.1 Plates accepted in accordance with this specificationshall be identified by stamping or stenciling UT 435 adjacent tomarking required by the material specification.S
25、UPPLEMENTARY REQUIREMENTSThe following shall apply only if specified in the order:S1. Instead of the scanning procedure specified by 5.4 and5.5, and as agreed upon between manufacturer and purchaser,100 % of one major plate surface shall be scanned. Scanningshall be continuous along parallel paths,
26、transverse or parallelto the major plate axis, with not less than 10 % overlapbetween each path.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 determin
27、ation 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 andif not revised, either reapproved or wit
28、hdrawn. 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 committee, which you may attend. If you feel that yo
29、ur 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,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).A 435/A 435M 90 (2007)2
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