ASTM E1742-2008 Standard Practice for Radiographic Examination.pdf

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1、Designation: E 1742 08Standard Practice forRadiographic Examination1This standard is issued under the fixed designation E 1742; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indi

2、cates 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 This practice2establishes the minimum requirements forradiographic examination f

3、or metallic and nonmetallic materi-als.1.2 ApplicabilityThe criteria for the radiographic exami-nation in this practice are applicable to all types of metallic andnonmetallic materials. The requirements expressed in thispractice are intended to control the quality of the radiographicimages and are n

4、ot intended to establish acceptance criteria forparts and materials.1.3 Basis of ApplicationThere are areas in this practicethat may require agreement between the cognizant engineeringorganization and the supplier, or specific direction from thecognizant engineering organization. These items should

5、beaddressed in the purchase order or the contract.1.3.1 DoD contracts.1.3.2 Personnel qualification, 5.1.1.1.3.3 Agency qualification, 5.1.2.1.3.4 Digitizing techniques, 5.4.5.1.3.5 Alternate image quality indicator (IQI) types, 5.5.3.1.3.6 Examination sequence, 6.6.1.3.7 Non-film techniques, 6.7.1.

6、3.8 Radiographic quality levels, 6.9.1.3.9 Film density, 6.10.1.3.10 IQI qualification exposure, 6.13.3.1.3.11 Non-requirement for IQI, 6.18.4.1.3.12 Examination coverage for welds, A2.2.2.1.3.13 Electron beam welds, A2.3.1.3.14 Geometric unsharpness, 6.23.1.3.15 Responsibility for examination, 6.27

7、.1.1.3.16 Examination report, 6.27.2.1.3.17 Retention of radiographs, 6.27.8.1.3.18 Storage of radiographs, 6.27.9.1.3.19 Reproduction of radiographs, 6.27.10 and 6.27.10.1.1.3.20 Acceptable parts, 6.28.1.1.4 This standard does not purport to address all of thesafety concerns, if any, associated wit

8、h 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 prior to use.2. Referenced Documents2.1 The following documents form a part of this practice tothe extent specified herein:

9、2.2 ASTM Standards:3E 543 Specification for Agencies Performing Nondestruc-tive TestingE 747 Practice for Design, Manufacture and MaterialGrouping Classification of Wire Image Quality Indicators(IQI) Used for RadiologyE 801 Practice for Controlling Quality of Radiological Ex-amination of Electronic

10、DevicesE 999 Guide for Controlling the Quality of Industrial Ra-diographic Film ProcessingE 1025 Practice for Design, Manufacture, and MaterialGrouping Classification of Hole-Type Image Quality Indi-cators (IQI) Used for RadiologyE 1030 Test Method for Radiographic Examination of Me-tallic CastingsE

11、 1032 Test Method for Radiographic Examination ofWeldmentsE 1079 Practice for Calibration of Transmission Densitom-etersE 1165 Test Method for Measurement of Focal Spots ofIndustrial X-Ray Tubes by Pinhole ImagingE 1254 Guide for Storage of Radiographs and UnexposedIndustrial Radiographic FilmsE 125

12、5 Practice for RadioscopyE 1316 Terminology for Nondestructive ExaminationsE 1390 Specification for Illuminators Used for ViewingIndustrial RadiographsE 1411 Practice for Qualification of Radioscopic SystemsE 1416 Test Method for Radioscopic Examination of Weld-mentsE 1815 Test Method for Classifica

13、tion of Film Systems for1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.01 onRadiology (X and Gamma) Method.Current edition approved July 1, 2008. Published August 2008. Originallyapproved in 1995. Last pr

14、evious edition approved in 2006 as E 1742 - 06.2This practice replaced MIL-STD-453.3For 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 Summary pa

15、ge onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Industrial Radiography2.3 AWS Document:AWS A2.4 Symbols for Welding and Nondestructive Test-ing42.4 Aerospace Industries Association Document:NAS 410 Certification

16、 mechanical devices (see Footnote B).BCalibrated and recorded in accordance with ANSI Z540-1, or ISO 10012-1,asapplicable.CDocumentation of this check not required.DMay be extended to weekly when substantiated by actual technical/reliabilitydata and approved by the cognizant engineering organization

17、.EMeasured and recorded when solutions are changed during preventativemaintenance or repair.FMeasured and recorded during preventative maintenance or repair.GTemperatures shall be checked prior to each use. Daily documentation of thischeck is required.HEach shift or when maintenance is performed (bu

18、lb or aperture changed).IEvery 90 days or whenever the densitometer verification check is not withintolerance.JFixed viewing locations with acceptable and controlled ambient lighting condi-tions need not be re-verified as long as those conditions are maintained.E17420846.1.7 The IQI size and type, a

19、nd the required radiographicquality level. If alternate IQIs are used (see 5.5.3), includedetails of the design or reference to documents where suchinformation is found.6.1.8 Thickness and type of material for shims or blocks, orboth, if used.6.1.9 Name and address of the NDT facility and the date,

20、orrevision, of the procedure.6.1.10 Radiographic identification scheme used to correlatepart-to-film. If the examination procedures are similar formany components, a master written procedure may be usedthat covers the details common to a variety of components.Allwritten procedures shall be approved

21、by an individual qualifiedand certified as a Level III for radiography in accordance with5.1.1.6.2 Acceptance RequirementsWhen examination is per-formed in accordance with this practice, engineering drawings,specifications, or other applicable documents shall indicate thecriteria by which the compon

22、ents are judged acceptable.Complex components may be divided into zones and separatecriteria assigned to each zone in accordance with its designrequirements. When used, direct references toASTM referenceradiographic standards shall include the grade level for eachtype of discontinuity permitted for

23、each part or zone.NOTE 3Information on reference radiographs can be obtained fromthe Annual Book of ASTM Standards, Vol 03.03 or from ASTM Head-quarters.6.3 Surface PreparationComponents may be examinedwithout surface preparation or conditioning except as requiredto remove surface conditions that ma

24、y interfere with properinterpretation of radiographs.6.3.1 Castings, forgings, and weldments may be radio-graphed in the as-cast, as-forged, or as-welded conditionsprovided the following requirements are met.6.3.1.1 For castings and forgings, the surface condition shallnot interfere with evaluation.

25、6.3.1.2 Accessible surfaces of welds shall be prepared inaccordance with A2.1.6.4 Radiographic IdentificationEach radiograph shallcarry the identification or serial number of the component andview number, when multiple views are taken. Each radiographshall also carry the identification of the NDTfac

26、ility examiningthe component and the date of the examination. Radiographs ofa repair area shall be identified with R1, R2, R3, and so forth,indicating the number of times that repairs were attempted.Alternative schemes may be used for identification of repairradiographs so long as each film is clear

27、ly identified to relate toa particular repair area. For explosives and propellants, theconditioning temperature shall be identified on each X-ray filmif the ordnance has been conditioned to a temperature otherthan facility ambient for purposes of examination.6.5 Examination and CoverageThe number of

28、 parts ex-amined, and the radiographic coverage of each part shall be asspecified by drawings, radiographic techniques, radiographicmanuals, handbooks for aircraft technical orders, or otherspecifications, as applicable. Areas to be examined shall beidentified on the drawing by using the symbols in

29、accordancewithANSI/AWS A2.4 or other systems of designations that areeasily identified on the drawing. If the number of parts to beexamined and the amount of coverage of each part is notspecified, all parts shall be examined and shall receive 100 %radiographic coverage.6.6 Examination SequenceThe se

30、quence for radiographicexamination in the production operation should be specified inthe manufacturing or assembly process specification, contract,or purchase order. If not specified, radiographic examinationshall be performed at a stage in the process of manufacturingor assembly at which discontinu

31、ities can be detected. Radio-graphic examination may be performed before heat treatment,provided liquid penetrant or magnetic particle examinations areperformed after heat treatment.6.7 Nonfilm TechniquesWhen permitted by purchase or-der, contract, or specification, radioscopic examination shall bei

32、n accordance with Practice E 1255 and appropriate annex.Qualification of radioscopic systems shall be in accordancewith Practice E 1411. Prior approval of the detailed examina-tion, evaluation, and quality control procedures shall be ob-tained from the Level III radiographer of the cognizantengineer

33、ing organization (see 5.1.1).6.8 Multi-Film TechniquesFilm techniques with two ormore films of the same or different speeds in the same filmholder, to be used in either single or superimposed filmviewing, shall be permitted provided that the applicable radio-graphic quality level, and film density r

34、equirements (see 6.9and 6.10), are achieved for the area of interest.6.9 Radiographic Quality LevelsThe five quality levelslisted in Table 3 may be assigned on the basis of IQI thicknessand the perceptibility of one, two, or three holes in thehole-type IQI image on the radiograph. If the quality lev

35、el isnot specified on the drawing or other applicable documents, itshall be Level 2-2T. Unless otherwise specified by the cogni-zant engineering organization, hole-type IQIs used for exami-nation of material 0.25 in. or less in thickness shall be 0.005-in.minimum thickness.6.10 Film DensityFor singl

36、e-film viewing, the film den-sity shall be $1.5 in the area of interest. Where superimposedfilm viewing is used, the film density of the superimposed filmsshall be from 2.0 in the area of interest, and each individualfilm shall not have a film density below 1.0 in the area ofinterest. Film densities

37、 above 4.0 are permitted when agreedupon between the cognizant engineering organization and theNDT facility (see Note 1 of Fig. 1). In no case shall themaximum film density exceed 4.5. For single-film viewing,film densities less than 1.5 are permitted only when items notTABLE 3 Quality Levels of Exa

38、minationIQI DesignationRadiographicQuality LevelMaximum IQIThickness, %AMinimum HoleDiameterBEquivalent IQISensitivity, %C00 11T 1 1T 0.70 12T 1 2T 1.01 21T 2 1T 1.42 22T 2 2T 2.03 24T 2 4T 2.8AExpressed as a percentage of material thickness.BExpressed as multiple thickness of IQI.CEquivalent IQI se

39、nsitivity is that thickness of the IQI expressed as a percent-age of the specimen thickness in which a 2T hole would be clearly visible under thesame radiographic conditions.E1742085requiring an IQI (see 6.18) are examined. The maximumreadable film density depends on the film viewer used and itsmaxi

40、mum luminance (see 6.27.4). The maximum readable filmdensity shall always be posted on the viewer.6.11 Processing RadiographsRadiographs shall be freefrom blemishes which may interfere with film interpretation.6.12 IQI SelectionThe IQI thickness shall be based on athickness not greater than the nomi

41、nal thickness to be radio-graphed. For double-wall exposures and double-wall viewingtechniques, the IQI shall be based on the double-wall thicknessof the component. The IQI thicknesses that are in between, orsmaller than, the thickness increments in Fig. A1.1 (forexample, a hole-type IQI that is 0.0

42、025 or 0.006 in. thick) maybe used but are not mandatory. For double-wall exposures andsingle-wall viewing techniques, the IQI shall be based on thesingle-wall thickness of the component. In no case shall the IQIthickness be based on a thickness greater than the thickness tobe radiographed. For fabr

43、ication welds the IQI shall be selectedin accordance with Annex A2. For explosive/propellants,rocket motors, and their components, IQI selection shall be asspecified in accordance with Annex A3.6.13 Placement of IQIsAn IQI shall be placed on eachpart radiographed for the duration of exposure, unless

44、 anumber of identical parts are simultaneously exposed on asingle film. In such a case, a single IQI shall be placed upon thesource side of a part at the outer edge of the cone of radiationor farthest extremity of the exposure setup (that is, farthestfrom the radiation beam centerline). For examinat

45、ion ofirregular objects, the IQI shall be placed on the area of the partfarthest from the film. The IQIs shall be placed adjacent to thearea of interest, since accept/reject decisions cannot be made inthe area directly beneath the IQI. Where it is not practicable toNOTE 1This figure is a depiction o

46、f the abscissa axis: Maximum Allowable Film Density versus ordinate axis: Candela/m2and footlamberts ingraphical format from tabular data derived from Guide E 1390 and ISO 5580 (also known as EN 25580). Conversion from tabular data to a graph accountsfor the step in the line. For Film Viewer Output

47、of 10 000 Candela/m2(2919 Footlamberts), the MaximumAllowable Film Density shall be 3.0. Regardingthe ordinate axis: Candela/m2, the minimum luminance level required for the average human eye to achieve photopic eye response (that is wheremaximum resolution and contrast discrimination occurs) is at

48、10 candela/m2.At levels below this value the eye responds scotopically which means lowercontrast discrimination and resolution. While photopic vision typically occurs at a threshold of 10 candela/m2for the average human eye, this curve takesadvantage of the fact that at lower film densities most vie

49、wers can achieve an amount of light that guarantees that virtually all operators will be viewingfilm in the photopic vision mode, that is 30 candela/m2for densities 6)atD=4above fog and base. These double sided NDT film systemshave a high silver content and do not saturate as early as medical and classes III, W-A, W-B and W-C film systems. The basic advantage of increasingthe density is the increase of contrast with density. Since the contrast/noise ratio also increases (with the square root of density), the perception ofindications of small flaws improves with