1、Designation: A 578/A578M 96 (Reapproved 2001)Standard Specification forStraight-Beam Ultrasonic Examination of Plain and CladSteel Plates for Special Applications1This standard is issued under the fixed designation A 578/A578M; the number immediately following the designation indicates the yearof or
2、iginal adoption or, in the case of revision, 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.This standard has been approved for use by agencies of the Department of
3、 Defense.1. Scope1.1 This specification2covers the procedure and acceptancestandards for straight-beam, pulse-echo, ultrasonic examina-tion of rolled carbon and alloy plain and clad steel plates,38 in.10 mm in thickness and over, for special applications. Themethod will detect internal discontinuiti
4、es parallel to the rolledsurfaces. Three levels of acceptance standards are provided.Supplementary requirements are provided for examination ofclad plate and for alternative procedures.1.2 Individuals performing examinations in accordance withthis specification shall be qualified and certified in ac
5、cordancewith the requirements of the latest edition of ASNT SNT-TC-1A or an equivalent accepted standard. 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
6、either inch-pound units or SI unitsare to be regarded separately as standard. Within the text, theSI units 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
7、in nonconformance with the specifi-cation.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulator
8、y limitations prior to use.2. Referenced Documents2.1 ASTM Standards:A 263 Specification for Corrosion-Resisting ChromiumSteel-Clad Plate, Sheet, and Strip3A 264 Specification for Stainless Chromium-Nickel Steel-Clad Plate, Sheet, and Strip3A 265 Specification for Nickel and Nickel-Base Alloy-CladSt
9、eel Plate32.2 ANSI Standard:B 46.1 Surface Texture42.3 ASNT Standard:SNT-TC-1A53. Ordering Information3.1 The inquiry and order shall indicate the following:3.1.1 Acceptance level requirements (Sections 7, 8, and 9).Acceptance Level B shall apply unless otherwise agreed to bypurchaser and manufactur
10、er.3.1.2 Any additions to the provisions of this specification asprescribed in 5.2, 13.1, and Section 10.3.1.3 Supplementary requirements, if any.4. Apparatus4.1 The amplitude linearity shall be checked by positioningthe transducer over the depth resolution notch in the IIW orsimilar block so that t
11、he signal from the notch is approximately30 % of the screen height, and the signal from one of the backsurfaces is approximately 60 % of the screen height (two timesthe height of the signal from the notch). A curve is then plottedshowing the deviations from the above established 2:1 ratiothat occurs
12、 as the amplitude of the signal from the notch israised in increments of one scale division until the backreflection signal reaches full scale, and then is lowered inincrements of one scale division until the notch signal reachesone scale division. At each increment the ratio of the twosignals is de
13、termined. The ratios are plotted on the graph at theposition corresponding to the larger signal. Between the limitsof 20 and 80 % of the screen height, the ratio shall be within1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the
14、direct responsibility of SubcommitteeA01.11 on Steel Plates for Boilers and Pressure Vessels.Current edition approved March 10, 2001. Published November 1996. Originallypublished as A 578 67 T. Last previous edition A 578/A 578M 92.2For ASME Boiler and Pressure Vessel Code applications, see related
15、Specifi-cation SA-578/SA-578M in Section II of that Code.3Annual Book of ASTM Standards, Vol 01.03.4Available from American National Standards Institute, 11 W. 42nd St., 13thfloor, New York, NY 10036.5Available from American Society for Nondestructive Testing, 1711 ArlingatePlaza, Columbus, OH 43228
16、.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.10 % of 2:1. Instrument settings used during inspection shallnot cause variation outside the 10 % limits established above.4.2 The transducer shall be 1 or 118 in. 25 or 30 mm indiamet
17、er or 1 in. 25 mm square.4.3 Other search units may be used for evaluating andpinpointing indications.5. Procedure5.1 Perform the inspection in an area free of operations thatinterfere with proper performance of the test.5.2 Unless otherwise specified, make the ultrasonic exami-nation on either majo
18、r surface of the plate.5.3 The plate surface shall be sufficiently clean and smoothto maintain a first reflection from the opposite side of the plateat least 50 % of full scale during scanning. This may involvesuitable means of scale removal at the manufacturers option.Condition local rough surfaces
19、 by grinding. Restore anyspecified identification which is removed when grinding toachieve proper surface smoothness.5.4 Perform the test by one of the following methods: directcontact, immersion, or liquid column coupling. Use a suitablecouplant such as water, soluble oil, or glycerin. As a result
20、ofthe test by this method, the surface of plates may be expectedto have a residue of oil or rust or both.5.5 A nominal test frequency of 214 MHz is recommended.When testing plates less than34 in. 20 mm thick a frequencyof 5 MHz may be necessary. Thickness, grain size or micro-structure of the materi
21、al and nature of the equipment or methodmay require a higher or lower test frequency. Use the trans-ducers at their rated frequency. A clean, easily interpreted tracepattern should be produced during the examination.5.6 Scanning:5.6.1 Scanning shall be along continuous perpendicular gridlines on nom
22、inal 9-in. 225-mm centers, or at the option of themanufacturer, shall be along continuous parallel paths, trans-verse to the major plate axis, on nominal 4-in. 100-mmcenters, or shall be along continuous parallel paths parallel tothe major plate axis, on 3-in. 75-mm or smaller centers.Measure the li
23、nes from the center or one corner of the platewith an additional path within 2 in. 50 mm of all edges of theplate on the searching surface.5.6.2 Conduct the general scanning with an instrumentadjustment that will produce a first reflection from the oppositeside of a sound area of the plate from 50 t
24、o 90 % of full scale.Minor sensitivity adjustments may be made to accommodatefor surface roughness.5.6.3 When a discontinuity condition is observed duringgeneral scanning adjust the instrument to produce a firstreflection from the opposite side of a sound area of the plate of75 6 5 % of full scale.
25、Maintain this instrument setting duringevaluation of the discontinuity condition.6. Recording6.1 Record all discontinuities causing complete loss of backreflection.6.2 For plates34 in. 20 mm thick and over, record allindications with amplitudes equal to or greater than 50 % of theinitial back reflec
26、tion and accompanied by a 50 % loss of backreflection.NOTE 1Indications occurring midway between the initial pulse andthe first back reflection may cause a second reflection at the location of thefirst back reflection. When this condition is observed it shall be investi-gated additionally by use of
27、multiple back reflections.6.3 Where grid scanning is performed and recordable con-ditions as in 6.1 and 6.2 are detected along a given grid line, theentire surface area of the squares adjacent to this indicationshall be scanned. Where parallel path scanning is performedand recordable conditions as i
28、n 6.1 and 6.2 are detected, theentire surface area ofa9by9-in. 225 by 225-mm squarecentered on this indication shall be scanned. The true bound-aries where these conditions exist shall be established in eithermethod by the following technique: Move the transducer awayfrom the center of the discontin
29、uity until the height of the backreflection and discontinuity indications are equal. Mark theplate at a point equivalent to the center of the transducer.Repeat the operation to establish the boundary.7. Acceptance StandardLevel A7.1 Any area where one or more discontinuities produce acontinuous tota
30、l loss of back reflection accompanied by con-tinuous indications on the same plane that cannot be encom-passed within a circle whose diameter is 3 in. 75 mm or12 ofthe plate thickness, whichever is greater, is unacceptable.8. Acceptance StandardsLevel B8.1 Any area where one or more discontinuities
31、produce acontinuous total loss of back reflection accompanied by con-tinuous indications on the same plane that cannot be encom-passed within a circle whose diameter is 3 in. 75 mm or12 ofthe plate thickness, whichever is greater, is unacceptable.8.2 In addition, two or more discontinuities smaller
32、thandescribed in 8.1 shall be unacceptable unless separated by aminimum distance equal to the greatest diameter of the largerdiscontinuity or unless they may be collectively encompassedby the circle described in 8.1.9. Acceptance StandardLevel C9.1 Any area where one or more discontinuities produce
33、acontinuous total loss of back reflection accompanied by con-tinous indications on the same plane that cannot be encom-passed within a 1-in. 25-mm diameter circle is unacceptable.10. Report10.1 Unless otherwise agreed to by the purchaser and themanufacturer, the manufacturer shall report the followi
34、ng data:10.1.1 All recordable indications listed in Section 6 on asketch of the plate with sufficient data to relate the geometryand identity of the sketch to those of the plate.10.1.2 Test parameters including: Make and model of in-strument, test frequency, surface condition, transducer (typeand fr
35、equency), and couplant.10.1.3 Date of test.11. Inspection11.1 The inspector representing the purchaser shall haveaccess at all times, while work on the contract of the purchaseris being performed, to all parts of the manufacturers worksthat concern the ultrasonic testing of the material ordered. The
36、A 578/A578M 96 (2001)2manufacturer shall afford the inspector all reasonable facilitiesto satisfy him that the material is being furnished in accordancewith this specification. All tests and inspections shall be madeat the place of manufacture prior to shipment, unless otherwisespecified, and shall
37、be conducted without interfering unneces-sarily with the manufacturers operations.12. Rehearing12.1 The manufacturer reserves the right to discuss reject-able ultrasonically tested plate with the purchaser with theobject of possible repair of the ultrasonically indicated defectbefore rejection of th
38、e plate.13. Marking13.1 Plates accepted according to this specification shall beidentified by stenciling (stamping) “UT A 578A” on onecorner for Level A, “UT A 578B” for Level B, and “UT A578C” for Level C. The supplement number shall be addedfor each supplementary requirement ordered.14. Keywords14
39、.1 nondestructive testing; pressure containing parts; pres-sure vessel steels; steel plate for pressure vessel applications;steel plates; ultrasonic examinationsSUPPLEMENTARY REQUIREMENTSThese supplementary requirements shall apply only when individually specified by the purchaser.When details of th
40、ese requirements are not covered herein, they are subject to agreement between themanufacturer and the purchaser.S1. ScanningS1.1 Scanning shall be continuous over 100 % of the platesurface.S2. Acceptance StandardS2.1 Any recordable condition listed in Section 6 that (1)iscontinuous, (2) is on the s
41、ame plane (within 5 % of the platethickness), and (3) cannot be encompassed by a 3-in. 75-mmdiameter circle, is unacceptable. Two or more recordableconditions (see Section 5), that (1) are on the same plane(within 5 % of plate thickness), (2) individually can beencompassed by a 3-in. 75-mm diameter
42、circle, (3) areseparated from each other by a distance less than the greatestdimension of the smaller indication, and (4) collectively cannotbe encompassed by a 3-in. 75-mm diameter circle, areunacceptable.S2.2 An acceptance level more restrictive than Section 7 or8 shall be used by agreement betwee
43、n the manufacturer andpurchaser.S3. ProcedureS3.1 The manufacturer shall provide a written procedure inaccordance with this specification.S4. CertificationS4.1 The manufacturer shall provide a written certificationof the ultrasonic test operators qualifications.S5. Surface FinishS5.1 The surface fin
44、ish of the plate shall be conditioned toa maximum 125 in. 3 mAA(seeANSI B 46.1) prior to test.S6. Examination of Integrally Bonded Clad Plate,Acceptance Level S 6S6.1 Examine the plate from the clad surface using proce-dures and techniques in accordance with this specification.S6.2 Inspect the backi
45、ng steel to Level B or, if specificallyrequested by customer, to Level A or Level C.S6.3 The cladding shall be interpreted to be unbonded whenthere is complete loss of back reflection accompanied by anecho indication from the plane of the interface of the clad andbacking steel.S6.4 Unless otherwise
46、specified, indications of unbonddetermined in accordance with S 6.3 that cannot be encom-passed within a 3-in. 75-mm diameter circle shall be weldrepaired subject to the requirements and limitations for therepair of defects in cladding of the appropriate materialspecification.S6.5 This supplementary
47、 requirement is applicable to Speci-fications A 263, A 264, and A 265.S7. Examination of Integrally Bonded Clad Plate,Acceptance Level S 7S7.1 The plate shall be examined from the clad surfaceusing procedures and techniques according to this specificationexcept 100 % surface search is mandatory.S7.2
48、 Inspect the backing steel to Level B or, if specificallyrequested by customer, to Level A or Level C.S7.3 The cladding shall be interpreted to be unbonded whenthere is complete loss of back reflection accompanied by anecho indication from the plane of the interface of the clad andbacking steel.S7.4
49、 Unless otherwise specified, indications of unbonddetermined in accordance with S 7.3 that cannot be encom-passed within a 1-in. 25-mm diameter circle shall be weldrepaired subject to the requirements and limitations for therepair of defects in cladding of the appropriate materialspecification. Additionally, prior approval must be obtained ifthe weld repaired surface exceeds 1.5 % of the claddingsurface.S7.5 This supplementary requirement is applicable to Speci-fications A 263, A 264, and A 265.A 578/A578M 96 (2001)3S8. Ultr
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