1、Designation: E280 10Standard Reference Radiographs forHeavy-Walled (412 to 12-in. (114 to 305-mm) Steel Castings1This standard is issued under the fixed designation E280; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These reference radiographs2illustrat
3、e various catego-ries, types, and severity levels of discontinuities occurring insteel castings that have section thicknesses of 412 to 12 in. (114to 305 mm). The reference radiograph films are an adjunct tothis document and must be purchased separately from ASTMInternational, if needed (see 2.2). C
4、ategories and severitylevels for each discontinuity type represented by these refer-ence radiographs are described in 1.2.NOTE 1The basis of application for these reference radiographsrequires a prior purchaser supplier agreement of radiographic examinationattributes and classification criterion as
5、described in Sections 4, 6, and 7of this standard. Reference radiographs for other steel casting thicknessesmay be found in Reference Radiograph standards E446 and E186.Reference radiograph E186 provides some overlap of severity levels forsimilar discontinuity categories within the same energy level
6、 range (see4.2, 5.1, and 6.3).1.2 These reference radiographs consist of two separatevolumes as follows1.2.1 Volume I: 2-MV X-rays and Cobalt-60This includescobalt-60 or equivalent isotope radiation and from 2-MV up to4-MV X-rays. Set of 28 plates in 812 by 11 in. (216 by 279mm) ring binders.1.2.2 V
7、olume II: 4-MV to 30-MV X-raysSet of 28 plates in812 by 11 in. (216 by 279 mm) ring binders.1.2.3 Unless otherwise specified in a purchaser supplieragreement (see 1.1), each volume is for comparison only withproduction radiographs produced with radiation energy levelswithin the thickness range cover
8、ed by this standard. Eachvolume consists of three categories of graded discontinuities inincreasing severity levels, and three categories of ungradeddiscontinuities. Reference radiographs containing ungradeddiscontinuities are provided as a guide for recognition of aspecific casting discontinuity ty
9、pe where severity levels are notneeded. Following is a list of discontinuity categories, typesand severity levels for the adjunct reference radiographs of thisstandard:1.2.3.1 Category AGas porosity; severity levels 1 through5.1.2.3.2 Category BSand and slag inclusions; severitylevels 1 through 5.1.
10、2.3.3 Category CShrinkage; three types:(1) Ca Linear ShrinkageSeverity levels 1 through 5(called Type 1 in previous revisions).(2) Cb Feathery ShrinkageSeverity levels 1 through 5(called Type 2 in previous revisions).(3) Cc Sponge ShrinkageSeverity levels 1 through 5(called Type 3 in previous revisi
11、ons).1.2.3.4 Category DCrack; one illustration D5 in pre-1972documents.1.2.3.5 Category EHot tear; one illustration D3 in pre-1972 documents.1.2.3.6 Category FInsert; one illustration EB2 in pre-1972 documents.1.3 The values stated in inch-pound units are to be regardedas the standard. SI values are
12、 shown for information only.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 regulatory limitations
13、prior to use.2. Referenced Documents2.1 ASTM Standards:3E94 Guide for Radiographic ExaminationE186 Reference Radiographs for Heavy-Walled (2 to 412-in. 51 to 114-mm) Steel CastingsE242 Reference Radiographs for Appearances of Radio-graphic Images as Certain Parameters Are ChangedE446 Reference Radio
14、graphs for Steel Castings Up to 2 in.51 mm in Thickness1These reference radiographs are under the jurisdiction of ASTM CommitteeE07 on Nondestructive Testing and are the direct responsibility of SubcommitteesE07.02 on Reference Radiological Images and E07.93 on Illustration Monitoring.Current editio
15、n approved Jan. 1, 2010. Published February 2010. Originallyapproved in 1965. Last previous edition approved in 2004 as E280 - 98(2004)1.DOI: 10.1520/E0280-10.2For ASME Boiler and Pressure Vessel Code applications see related ReferenceRadiographs SE 280 in Section V of that Code.3For referenced ASTM
16、 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 Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
17、ken, PA 19428-2959, United States.E1316 Terminology for Nondestructive Examinations2.2 ASTM Adjuncts:4Reference Radiographs for Heavy-Walled (412 to 12-in.(114 to 305-mm) Steel Castings:Volume I, 2-MV to 4 MV X-rays and Cobalt-605Volume II, 4-MV to 30-MV X-Ray63. Terminology3.1 DefinitionsFor defini
18、tions of terms relating to radio-graphic examination, see Terminology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 production radiographa radiograph under reviewfor compliance with this standard.3.2.2 discontinuity typea specific discontinuity character-ized by its cause and appear
19、ance. For example: linear shrink-age is a specific discontinuity type.3.2.3 discontinuity categorya nomenclature system usedfor grouping discontinuity types. For example: linear shrinkageis assigned category “Ca” where “C” represents the generalshrinkage category and “a” represents the specific line
20、arshrinkage discontinuity type.3.2.4 discontinuity severity levela relative rank in termsof “quantity, size and distribution” of a collection of disconti-nuities where “1” is the least and “5” is the greatest “quantity,size and distribution” present on the reference radiograph.Example: a severity le
21、vel of “1” is more restrictive (requires ahigher level of workmanship fabrication quality) than a sever-ity level of “2”.3.2.5 discontinuity classan assigned workmanship fabri-cation quality rating characterized by a discontinuity type,category and severity level. For example: “Ca 2” is a discon-tin
22、uity class comprised of linear shrinkage with a severity levelof “2”.3.2.6 classification specificationa set of user defined ac-ceptance criterion that prescribes the radiographic workman-ship discontinuity class requirements for a specified usercasting service application (see Sections 6 and 7).3.2
23、.7 graded illustrationa category of discontinuity that isassigned a severity level.3.2.8 ungraded illustrationa category of discontinuitywithout an assigned severity level.3.2.9 proratingassignment of quantity, size and distribu-tion on a production radiograph in proportion to a similar sizearea of
24、a reference radiograph. For example: a productionradiograph covers an area that is smaller than the unit area ofa reference radiograph and the extent of discontinuity on theapplicable reference radiograph is reduced proportionately.4. Significance and Use4.1 Graded reference radiographs are intended
25、 to provide aguide enabling recognition of specific casting discontinuitytypes and relative severity levels that may be encounteredduring typical fabrication processes. Reference radiographscontaining ungraded discontinuities are provided as a guide forrecognition of a specific casting discontinuity
26、 type whereseverity levels may not be needed. These reference radiographsare intended as a basis from which manufacturers and purchas-ers may, by mutual agreement, select particular workmanshipclasses to serve as standards representing minimum levels ofacceptability (see Sections 6 and 7).4.2 Refere
27、nce radiographs represented by this standard maybe used, as agreed upon in a purchaser supplier agreement, forenergy levels, thicknesses or both outside the range of thisstandard when determined applicable for the casting serviceapplication. Overlapping severity levels of similar discontinu-ity cate
28、gories and energy level range of E186 referenceradiographs may alternatively be used, as determined appro-priate for the casting service application, if so agreed upon ina purchaser supplier agreement (see 5.1).4.3 Procedures for evaluation of production radiographsusing applicable reference radiogr
29、aphs of this standard areprescribed in Section 8; however, there may be manufacturing-purchaser issues involving specific casting service applicationswhere it may be appropriate to modify or alter such require-ments. Where such modifications may be appropriate for thecasting application, all such ch
30、anges shall be specificallycalled-out in the purchaser supplier agreement or contractualdocument. Section 9 addresses purchaser supplier requisiteswhere weld repairs may be required.5. Method of Preparation5.1 The original radiographs used to prepare the adjunctreference radiographs were produced on
31、 ASTM Class I or IIfilm systems by the respective use of radiation energies statedin 1.2.1 and 1.2.2. The original radiographs were made with apenetrameter sensitivity as determined by ASTM penetram-eters (see Guide E94) of 2-2T. The adjunct reference radio-graphs are reproductions prepared to an op
32、tical density of 2.00to 2.25 and they have substantially retained the contrast of theoriginal radiographs. In preparing these reference radiographs,the objective was to obtain progressively graduated severitylevels for each graded discontinuity category over the thicknessrange of this standard. Addi
33、tionally, some overlap of severitylevels may occur for similar discontinuity categories of Refer-ence Radiograph standard E186 with the same energy levelrange. For example, aggregate gas porosity severity level 1 ofthis standard is less severe than aggregate porosity severitylevel 5 of E186 (see 6.3
34、).5.2 Film DeteriorationRadiographic films are subject towear and tear from handling and use. The extent to which theimage deteriorates over time is a function of storage condi-tions, care in handling and amount of use. Reference radio-graph films are no exception and may exhibit a loss in imagequal
35、ity over time. The radiographs should therefore be peri-odically examined for signs of wear and tear, includingscratches, abrasions, stains, and so forth. Any reference radio-graphs which show signs of excessive wear and tear whichcould influence the interpretation and use of the radiographsshould b
36、e replaced.6. Determination of Radiographic Classification6.1 For purposes of evaluation of castings, a determinationmust be made of the radiographic discontinuity classification to4Available from ASTM Headquarters.5Order RRE028001.6Order RRE028002.E280 102be assigned to individual castings or speci
37、fic areas of castings.The determination of the applicable radiographic discontinuityclassification shall be based on an evaluation of the castingapplications, design, and service requirements. In these evalu-ations, consideration shall be given to such factors as pressure,temperature, section thickn
38、ess, applicable design safety factor,vibration, shock, resistance to corrosion, involvement of pen-etrating radiations or radiation products, and involvement ofdangerous gases or liquids.6.2 For each individual casting or specific area of a castingto be radiographed, the discontinuity class must be
39、clearlyspecified. For example: severity level 2 might be specified forlinear shrinkage, Category Ca, and severity level 3 for gasporosity, Category A, since the latter are generally much lessdeleterious to tensile properties (see Section 7).6.3 When determining discontinuity severity levels for in-d
40、ividual castings spanning multiple thickness ranges outsidethe range of this standard, consideration should be given to thepotential for overlapping severity levels as described in 4.2 andSection 5.6.4 Production radiographs which are compared to refer-ence radiographs should have an optical density
41、 in the area ofinterest in accordance with Guide E94 and a specified mini-mum radiographic sensitivity (quality level) of 2 % (2-2T).5Other radiographic quality levels or optical densities may bedesignated, but then a corresponding change in severity levelfor each discontinuity category should be an
42、ticipated and hencespecified.7. Classification Specifications7.1 The applicable radiographic discontinuity classificationshould be designated by the contracting agency in formalspecifications or drawings and in the specific contract or order.The specifications, drawings, contract, or order should al
43、sodesignate the sampling plan for the castings to be radiographedand the extent of radiographic coverage, radiographic practiceto be followed (Guide E94), image quality desired (see Note 2)as well as the severity of acceptable discontinuity for gradedcategories.NOTE 2For description of sensitivity o
44、r image quality levels, seeGuide E94 and Reference Radiograph standard E242.8. Procedure for Evaluation8.1 Compare the production radiographs of the castingsubmitted for evaluation with the reference radiographs ex-posed at an equivalent energy range within the thickness rangeof this standard (unles
45、s otherwise specifiedsee Section 4).8.2 When the severity level of discontinuities in the produc-tion radiograph being evaluated is equal to or less than theseverity level in the specified reference radiograph, that part ofthe casting represented by the production radiograph shall beacceptable. If t
46、he production radiograph shows discontinuitiesof greater severity than the reference radiograph, that part ofthe casting shall be rejected.8.3 A unit area on the production radiograph shall beevaluated to a unit area of like size on the reference radiograph.Any evaluation unit area that shares a dis
47、continuity with anadjacent unit evaluation area shall meet the minimum unit areaacceptability requirements within the combined unit area.When the unit area of interest of a production radiograph is lessthan the unit area of the applicable reference radiograph, suchunit area of the production radiogr
48、aph shall be prorated to thereference radiographic area.8.4 When two or more categories of discontinuity arepresent in the same production radiograph, the predominatingdiscontinuities, if unacceptable, shall govern without regard tothe other categories of discontinuity and that part of the castingsh
49、all be judged unacceptable.8.5 When two or more categories of discontinuity arepresent to an extent equal to the maximum permissible level asshown in the applicable standards for each category, then thatpart of the casting shall be judged unacceptable. When two ormore categories of discontinuity are present in the sameradiograph to an extent less than the maximum permissiblelevel, as shown in the applicable standards for each category,the severity shall be evaluated by the overall aggregatecondition. The aggregate condition is defined as the balanc
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