1、Designation: E94 04 (Reapproved 2010)Standard Guide forRadiographic Examination1This standard is issued under the fixed designation E94; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of last revision.Anumber in parenthes
2、es indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide2covers satisfactory X-ray and gamma-rayradiographic examination as applied to industrial radiographicfilm recording. It includes statements about
3、 preferred practicewithout discussing the technical background which justifies thepreference. A bibliography of several textbooks and standarddocuments of other societies is included for additional infor-mation on the subject.1.2 This guide covers types of materials to be examined;radiographic exami
4、nation techniques and production methods;radiographic film selection, processing, viewing, and storage;maintenance of inspection records; and a list of availablereference radiograph documents.NOTE 1Further information is contained in Guide E999, PracticeE1025, Test Methods E1030, and E1032.1.3 Inter
5、pretation and Acceptance StandardsInterpretation and acceptance standards are not covered by thisguide, beyond listing the available reference radiograph docu-ments for castings and welds. Designation of accept - rejectstandards is recognized to be within the cognizance of productspecifications and
6、generally a matter of contractual agreementbetween producer and purchaser.1.4 Safety PracticesProblems of personnel protectionagainst X rays and gamma rays are not covered by thisdocument. For information on this important aspect of radiog-raphy, reference should be made to the current document of t
7、heNational Committee on Radiation Protection and Measure-ment, Federal Register, U.S. Energy Research and Develop-ment Administration, National Bureau of Standards, and tostate and local regulations, if such exist. For specific radiationsafety information refer to NIST Handbook ANSI 43.3, 21CFR 1020
8、.40, and 29 CFR 1910.1096 or state regulations foragreement states.1.5 This standard does not purport to address all of thesafety problems, 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 ap
9、plica-bility of regulatory limitations prior to use. (See 1.4.)1.6 If an NDT agency is used, the agency shall be qualifiedin accordance with Practice E543.2. Referenced Documents2.1 ASTM Standards:3E543 Specification for Agencies Performing Nondestruc-tive TestingE746 Practice for Determining Relati
10、ve Image QualityResponse of Industrial Radiographic Imaging SystemsE747 Practice for Design, Manufacture and MaterialGrouping Classification of Wire Image Quality Indicators(IQI) Used for RadiologyE801 Practice for Controlling Quality of Radiological Ex-amination of Electronic DevicesE999 Guide for
11、Controlling the Quality of Industrial Radio-graphic Film ProcessingE1025 Practice for Design, Manufacture, and MaterialGrouping Classification of Hole-Type Image Quality Indi-cators (IQI) Used for RadiologyE1030 Test Method for Radiographic Examination of Me-tallic CastingsE1032 Test Method for Radi
12、ographic Examination of Weld-mentsE1079 Practice for Calibration of Transmission Densitom-etersE1254 Guide for Storage of Radiographs and UnexposedIndustrial Radiographic FilmsE1316 Terminology for Nondestructive ExaminationsE1390 Specification for Illuminators Used for ViewingIndustrial Radiographs
13、E1735 Test Method for Determining Relative Image Qual-ity of Industrial Radiographic Film Exposed toX-Radiation from 4 to 25 MeVE1742 Practice for Radiographic ExaminationE1815 Test Method for Classification of Film Systems forIndustrial Radiography2.2 ANSI Standards:PH1.41 Specifications for Photog
14、raphic Film for Archival1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.01 on Radiology(X and Gamma) Method.Current edition approved June 1, 2010. Published November 2010. Originallyapproved in 1952. Last pre
15、vious edition approved in 2004 as E94 - 04. DOI:10.1520/E0094-04R10.2For ASME Boiler and Pressure Vessel Code applications see related GuideSE-94 in Section V of that Code.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For An
16、nual 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 Conshohocken, PA 19428-2959, United States.Records, Silver-Gelatin Type, on Polyester Base4PH2.22 Methods for Determi
17、ning Safety Times of Photo-graphic Darkroom Illumination4PH4.8 Methylene Blue Method for Measuring Thiosulfateand Silver Densitometric Method for Measuring ResidualChemicals in Films, Plates, and Papers4T9.1 Imaging Media (Film)Silver-Gelatin Type Specifi-cations for Stability4T9.2 Imaging MediaPhot
18、ographic Process Film Plate andPaper Filing Enclosures and Storage Containers42.3 Federal Standards:Title 21, Code of Federal Regulations (CFR) 1020.40,Safety Requirements of Cabinet X-Ray Systems5Title 29, Code of Federal Regulations (CFR) 1910.96,Ionizing Radiation (X-Rays, RF, etc.)52.4 Other Doc
19、ument:NBS Handbook ANSI N43.3 General Radiation SafetyInstallations Using NonMedical X-Ray and SealedGamma Sources up to 10 MeV63. Terminology3.1 DefinitionsFor definitions of terms used in this guide,refer to Terminology E1316.4. Significance and Use4.1 Within the present state of the radiographic
20、art, thisguide is generally applicable to available materials, processes,and techniques where industrial radiographic films are used asthe recording media.4.2 LimitationsThis guide does not take into consider-ation special benefits and limitations resulting from the use ofnonfilm recording media or
21、readouts such as paper, tapes,xeroradiography, fluoroscopy, and electronic image intensifi-cation devices. Although reference is made to documents thatmay be used in the identification and grading, where appli-cable, of representative discontinuities in common metal cast-ings and welds, no attempt h
22、as been made to set standards ofacceptance for any material or production process. Radiogra-phy will be consistent in sensitivity and resolution only if theeffect of all details of techniques, such as geometry, film,filtration, viewing, etc., is obtained and maintained.5. Quality of Radiographs5.1 T
23、o obtain quality radiographs, it is necessary to consideras a minimum the following list of items. Detailed informationon each item is further described in this guide.5.1.1 Radiation source (X-ray or gamma),5.1.2 Voltage selection (X-ray),5.1.3 Source size (X-ray or gamma),5.1.4 Ways and means to el
24、iminate scattered radiation,5.1.5 Film system class,5.1.6 Source to film distance,5.1.7 Image quality indicators (IQIs),5.1.8 Screens and filters,5.1.9 Geometry of part or component configuration,5.1.10 Identification and location markers, and5.1.11 Radiographic quality level.6. Radiographic Quality
25、 Level6.1 Information on the design and manufacture of imagequality indicators (IQIs) can be found in Practices E747,E801, E1025, and E1742.6.2 The quality level usually required for radiography is2 % (2-2T when using hole type IQI) unless a higher or lowerquality is agreed upon between the purchase
26、r and the supplier.At the 2 % subject contrast level, three quality levels ofinspection, 2-1T, 2-2T, and 2-4T, are available through thedesign and application of the IQI (Practice E1025, Table 1).Other levels of inspection are available in Practice E1025Table1. The level of inspection specified shou
27、ld be based on theservice requirements of the product. Great care should be takenin specifying quality levels 2-1T, 1-1T, and 1-2T by firstdetermining that these quality levels can be maintained inproduction radiography.NOTE 2The first number of the quality level designation refers to IQIthickness e
28、xpressed as a percentage of specimen thickness; the secondnumber refers to the diameter of the IQI hole that must be visible on theradiograph, expressed as a multiple of penetrameter thickness, T.6.3 If IQIs of material radiographically similar to that beingexamined are not available, IQIs of the re
29、quired dimensionsbut of a lower-absorption material may be used.6.4 The quality level required using wire IQIs shall beequivalent to the 2-2T level of Practice E1025 unless a higheror lower quality level is agreed upon between purchaser andsupplier. Table 4 of Practice E747 gives a list of variousho
30、le-type IQIs and the diameter of the wires of correspondingEPS with the applicable 1T, 2T, and 4T holes in the plaque IQI.Appendix X1 of Practice E747 gives the equation for calcu-lating other equivalencies, if needed.7. Energy Selection7.1 X-ray energy affects image quality. In general, the lowerth
31、e energy of the source utilized the higher the achievableradiographic contrast, however, other variables such as geom-etry and scatter conditions may override the potential advan-tage of higher contrast. For a particular energy, a range ofthicknesses which are a multiple of the half value layer, may
32、 beradiographed to an acceptable quality level utilizing a particu-lar X-ray machine or gamma ray source. In all cases thespecified IQI (penetrameter) quality level must be shown onthe radiograph. In general, satisfactory results can normally beobtained for X-ray energies between 100 kV to 500 kV in
33、 arange between 2.5 to 10 half value layers (HVL) of materialthickness (see Table 1). This range may be extended by asmuch as a factor of 2 in some situations for X-ray energies inthe 1 to 25 MV range primarily because of reduced scatter.8. Radiographic Equivalence Factors8.1 The radiographic equiva
34、lence factor of a material is thatfactor by which the thickness of the material must be multi-plied to give the thickness of a “standard” material (often steel)4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.5Available from U.S. Government P
35、rinting Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.6Available from National Technical Information Service (NTIS), U.S. Depart-ment of Commerce, 5285 Port Royal Rd., Springfield, VA 22161.E94 04 (2010)2which has the same absorption. Radiographic eq
36、uivalencefactors of several of the more common metals are given inTable 2, with steel arbitrarily assigned a factor of 1.0. Thefactors may be used:8.1.1 To determine the practical thickness limits for radia-tion sources for materials other than steel, and8.1.2 To determine exposure factors for one m
37、etal fromexposure techniques for other metals.9. Film9.1 Various industrial radiographic film are available tomeet the needs of production radiographic work. However,definite rules on the selection of film are difficult to formulatebecause the choice depends on individual user requirements.Some user
38、 requirements are as follows: radiographic qualitylevels, exposure times, and various cost factors. Severalmethods are available for assessing image quality levels (seeTest Method E746, and Practices E747 and E801). Informationabout specific products can be obtained from the manufactur-ers.9.2 Vario
39、us industrial radiographic films are manufacturedto meet quality level and production needs. Test Method E1815provides a method for film manufacturer classification of filmsystems. A film system consist of the film and associated filmprocessing system. Users may obtain a classification table fromthe
40、 film manufacturer for the film system used in productionradiography.Achoice of film class can be made as provided inTest Method E1815. Additional specific details regardingclassification of film systems is provided in Test MethodE1815. ANSI Standards PH1.41, PH4.8, T9.1, and T9.2 pro-vide specific
41、details and requirements for film manufacturing.10. Filters10.1 DefinitionFilters are uniform layers of materialplaced between the radiation source and the film.10.2 PurposeThe purpose of filters is to absorb the softercomponents of the primary radiation, thus resulting in one orseveral of the follo
42、wing practical advantages:10.2.1 Decreasing scattered radiation, thus increasing con-trast.10.2.2 Decreasing undercutting, thus increasing contrast.10.2.3 Decreasing contrast of parts of varying thickness.10.3 LocationUsually the filter will be placed in one ofthe following two locations:10.3.1 As c
43、lose as possible to the radiation source, whichminimizes the size of the filter and also the contribution of thefilter itself to scattered radiation to the film.10.3.2 Between the specimen and the film in order to absorbpreferentially the scattered radiation from the specimen. Itshould be noted that
44、 lead foil and other metallic screens (see13.1) fulfill this function.10.4 Thickness and Filter Material The thickness andmaterial of the filter will vary depending upon the following:10.4.1 The material radiographed.10.4.2 Thickness of the material radiographed.10.4.3 Variation of thickness of the
45、material radiographed.10.4.4 Energy spectrum of the radiation used.10.4.5 The improvement desired (increasing or decreasingcontrast). Filter thickness and material can be calculated ordetermined empirically.11. Masking11.1 Masking or blocking (surrounding specimens or cov-ering thin sections with an
46、 absorptive material) is helpful inreducing scattered radiation. Such a material can also be usedto equalize the absorption of different sections, but the loss ofdetail may be high in the thinner sections.12. Back-Scatter Protection12.1 Effects of back-scattered radiation can be reduced byconfining
47、the radiation beam to the smallest practical crossTABLE 1 Typical Steel HVL Thickness in Inches (mm) forCommon EnergiesEnergyThickness,Inches (mm)120 kV 0.10 (2.5)150 kV 0.14 (3.6)200 kV 0.20 (5.1)250 kV 0.25 (6.4)400 kV (Ir 192) 0.35 (8.9)1 MV 0.57 (14.5)2 MV (Co 60) 0.80 (20.3)4 MV 1.00 (25.4)6 MV
48、 1.15 (29.2)10 MV 1.25 (31.8)16 MV and higher 1.30 (33.0)TABLE 2 Approximate Radiographic Equivalence Factors for Several Metals (Relative to Steel)MetalEnergy Level100 kV 150 kV 220 kV 250 kV 400 kV 1 MV 2 MV 4 to 25 MV192Ir60CoMagnesium 0.05 0.05 0.08Aluminum 0.08 0.12 0.18 0.35 0.35Aluminum alloy
49、 0.10 0.14 0.18 0.35 0.35Titanium 0.54 0.54 0.71 0.9 0.9 0.9 0.9 0.9Iron/all steels 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0Copper 1.5 1.6 1.4 1.4 1.4 1.1 1.1 1.2 1.1 1.1Zinc 1.4 1.3 1.3 1.2 1.1 1.0Brass 1.4 1.3 1.3 1.2 1.1 1.0 1.1 1.0Inconel X 1.4 1.3 1.3 1.3 1.3 1.3 1.3 1.3Monel 1.7 1.2Zirconium 2.4 2.3 2.0 1.7 1.5 1.0 1.0 1.0 1.2 1.0Lead 14.0 14.0 12.0 5.0 2.5 2.7 4.0 2.3Hafnium 14.0 12.0 9.0 3.0Uranium 20.0 16.0 12.0 4.0 3.9 12.6 3.4E94 04 (2010)3section and by placing lead behind the film. In some caseseither or both the back lead screen and the lead contained
