ASTM E1742-2008a Standard Practice for Radiographic Examination《放射照象检验的标准实施规程》.pdf

1、Designation: E 1742 08aStandard 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 ind

2、icates 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

3、for 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

4、not 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, 6.18.1.3.12 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 UnitsThe values stated in inch-pound units are to beregarded as standard. The values given i

8、n parentheses aremathematical conversions to SI units that are provided forinformation only and are not considered standard.1.5 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 appr

9、o-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:2.2 ASTM Standards:3E94 Guide for Radiographic ExaminationE 543 Specification for

10、 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 DevicesE 999 Guide for Controlling the Qual

11、ity 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 1032 Test Method for Radiographic Examinat

12、ion 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 1255 Practice for RadioscopyE 1316 Terminology

13、 for Nondestructive ExaminationsE 1390 Specification for Illuminators Used for Viewing1This 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 Dec. 15, 2

14、008. Published January 2009. Originallyapproved in 1995. Last previous edition approved in 2008 as E 1742 - 08.2This 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 ASTMStandard

15、s volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Industrial RadiographsE 1411 Practice for Qualification of Radioscopic SystemsE 1416 Test Method fo

16、r Radioscopic Examination of Weld-mentsE 1815 Test Method for Classification of Film Systems forIndustrial Radiography2.3 AWS Document:AWS A2.4 Symbols for Welding and Nondestructive Test-ing42.4 Aerospace Industries Association Document:NAS 410 Certification mechanical devices (see Footnote B).BCal

17、ibrated and recorded in accordance with ANSI Z540-1, or ISO 10012,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.EMeasured and recorded when solutions are

18、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 (bulb or aperture changed).IEvery 90 days or w

19、henever 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.E 1742 08a4spot size. For radioisotope sources, the isotope type, sourcestrength

20、(curies), exposure time, and source size.6.1.5 Film designation (for example, brand, type, and pro-cessing parameters), intensifying screens (for example, typeand thickness of screens), or filters (for example, filter material,thickness, and location) if used, film loading instructions, andthe desir

21、ed film density range.6.1.6 Thickness and type of material.6.1.7 The IQI size and type, and 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 s

22、hims or blocks, orboth, if used.6.1.9 Name and address of the NDT facility and the date, 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 cove

23、rs the details common to a variety of components.Allwritten procedures shall be approved 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,spe

24、cifications, or other applicable documents shall indicate thecriteria by which the components 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 referenceradiogra

25、phic standards shall include the grade level for eachtype of discontinuity permitted for 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 s

26、urface preparation or conditioning except as requiredto remove surface conditions that may 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

27、.1.1 For castings and forgings, the surface condition shallnot interfere with evaluation.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 m

28、ultiple views are taken. Each radiographshall also carry the identification of the NDTfacility 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

29、schemes may be used for identification of repairradiographs so long as each film is clearly 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 otherth

30、an facility ambient for purposes of examination.6.5 Examination and CoverageThe number of 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 ap

31、plicable. Areas to be examined shall beidentified on the drawing by using the symbols in 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 shal

32、l be examined and shall receive 100 %radiographic coverage.6.6 Examination SequenceThe sequence for radiographicexamination in the production operation should be specified inthe manufacturing or assembly process specification, contract,or purchase order. If not specified, radiographic examinationsha

33、ll be performed at a stage in the process of manufacturingor assembly at which discontinuities 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 pe

34、rmitted by purchase or-der, contract, or specification, radioscopic examination shall bein 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 contr

35、ol procedures shall be ob-tained from the Level III radiographer of the cognizantengineering 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

36、be permitted provided that the applicable radio-graphic quality level, and film density requirements (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

37、 one, two, or three holes in thehole-type IQI image on the radiograph. If the quality level 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 0.2

38、5 in. (6.35 mm) or less in thickness shallbe 0.005-in. (0.127-mm) minimum thickness.6.10 Film DensityFor single-film viewing, the film den-sity shall be $1.5 in the area of interest. Where superimposedTABLE 3 Quality Levels of ExaminationIQI DesignationRadiographicQuality LevelMaximum IQIThickness,

39、%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 sensitivity is that thickness of the IQI expressed as a percent-age of t

40、he specimen thickness in which a 2T hole would be clearly visible under thesame radiographic conditions.E 1742 08a5film 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 of

41、interest. Film densities 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 notrequi

42、ring an IQI (see 6.18) are examined. The maximumreadable film density depends on the film viewer used and itsmaximum 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 wi

43、th film interpretation.6.12 IQI SelectionThe IQI thickness shall be based on athickness not greater than the nominal 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 th

44、at are in between, orsmaller than, the thickness increments in Fig. A1.1 (forexample, a hole-type IQI that is 0.0025 or 0.006 in. (0.0635 or0.1524 mm) thick) may be used but are not mandatory. Fordouble-wall exposures and single-wall viewing techniques, theIQI shall be based on the single-wall thick

45、ness of the compo-nent. In no case shall the IQI thickness be based on a thicknessgreater than the thickness to be radiographed. For fabricationwelds the IQI shall be selected in accordance with Annex A2.For explosive/propellants, rocket motors, and their compo-nents, IQI selection shall be as speci

46、fied in accordance withAnnex A3.6.13 Placement of IQIsAn IQI shall be placed on eachpart radiographed for the duration of exposure, unless aNOTE 1This figure is a depiction of the abscissa axis: Maximum Allowable Film Density versus ordinate axis: Candela/m2and footlamberts ingraphical format from t

47、abular 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 of 10 000 Candela/m2(2919 Footlamberts), the MaximumAllowable Film Density shall be 3.0. Regardingthe ordinate axis: Candela/m

48、2, 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 10 candela/m2.At levels below this value the eye responds scotopically which means lowercontrast discrimination and resolution

49、. 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 viewers 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 t