ASTM E1742 E1742M-2011 Standard Practice for Radiographic Examination《放射照象检验标准操作规程》.pdf

1、Designation:E174208a Designation: E1742/E1742M 11Standard Practice forRadiographic Examination1This standard is issued under the fixed designation E1742/E1742M; the number immediately following the designation indicates the yearof original adoption or, in the case of revision, the year of last revis

2、ion. A number in parentheses indicates the year of last reapproval.A superscript 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. Scope*1.1 This practice2establishes the minimum requirem

3、ents for radiographic examination for metallic and nonmetallic materials.1.2 ApplicabilityThe criteria for the radiographic examination in this practice are applicable to all types of metallic andnonmetallic materials. The requirements expressed in this practice are intended to control the quality o

4、f the radiographic imagesand are not intended to establish acceptance criteria for parts and materials.1.3 Basis of ApplicationThere are areas in this practice that may require agreement between the cognizant engineeringorganization and the supplier, or specific direction from the cognizant engineer

5、ing organization. These items should be addressedin 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、6.6.1.3.7 Non-film techniques, 6.7.1.3.8 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 R

7、esponsibility for examination, 6.27.1.1.3.16 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 be reg

8、arded as standard. The values given in parentheses aremathematical conversions to SI units that are provided for information only and are not considered standard. The values statedin either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may n

9、ot be exactequivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may resultin non-conformance with the standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsib

10、ilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 The following documents form a part of this practice to the extent specified herein:1This practice is under the juri

11、sdiction ofASTM Committee E07 on Nondestructive Testing and is the direct responsibility of Subcommittee E07.01 on Radiology (X andGamma) Method.Current edition approved Dec. 15, 2008.Jan. 1, 2011. Published January 2009.February 2011. Originally approved in 1995. Last previous edition approved in 2

12、008 asE1742 - 08a. DOI: 10.1520/E1742-08A.10.1520/E1742-11.2This practice replaced MIL-STD-453.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically po

13、ssible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.

14、Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2.2 ASTM Standards:3E94 Guide for Radiographic ExaminationE543 Specification for Agencies Performing Nondestructive TestingE747 Practice for Design, Manufacture and Material Grouping Cla

15、ssification of Wire Image Quality Indicators (IQI) Used forRadiologyE801 Practice for Controlling Quality of Radiological Examination of Electronic DevicesE999 Guide for Controlling the Quality of Industrial Radiographic Film ProcessingE1025 Practice for Design, Manufacture, and Material Grouping Cl

16、assification of Hole-Type Image Quality Indicators (IQI)Used for RadiologyE1030 Test Method for Radiographic Examination of Metallic CastingsE1032 Test Method for Radiographic Examination of WeldmentsE1079 Practice for Calibration of Transmission DensitometersE1165 Test Method for Measurement of Foc

17、al Spots of Industrial X-Ray Tubes by Pinhole ImagingE1254 Guide for Storage of Radiographs and Unexposed Industrial Radiographic FilmsE1255 Practice for RadioscopyE1316 Terminology for Nondestructive ExaminationsE1390 Specification for Illuminators Used for Viewing Industrial RadiographsE1411 Pract

18、ice for Qualification of Radioscopic SystemsE1416 Test Method for Radioscopic Examination of WeldmentsE1815 Test Method for Classification of Film Systems for Industrial Radiography2.3 AWS Document:AWS A2.4Symbols for Welding and Nondestructive Testing Standard Symbols for Welding, Brazing, and Nond

19、estructiveExamination42.4 Aerospace Industries Association Document:NAS 410 Certification mechanical devices (see Footnote B).BCalibrated and recorded in accordance with ANSI Z540-13, or ISO 10012, asapplicable.CDocumentation of this check not required.DMay be extended to weekly when substantiated b

20、y actual technical/reliabilitydata and approved by the cognizant engineering organization.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. Dail

21、y documentation of thischeck is required.HEach shift or when maintenance is performed (bulb 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-v

22、erified as long as those conditions are maintained.E1742/E1742M 116NOTE 3Information on reference radiographs can be obtained from the Annual Book of ASTM Standards, Vol 03.03 or from ASTM Headquarters.6.3 Surface PreparationComponents may be examined without surface preparation or conditioning exce

23、pt as required toremove surface conditions that may interfere with proper interpretation of radiographs.6.3.1 Castings, forgings, and weldments may be radiographed in the as-cast, as-forged, or as-welded conditions provided thefollowing requirements are met.6.3.1.1 For castings and forgings, the sur

24、face condition shall not interfere with evaluation.6.3.1.2 Accessible surfaces of welds shall be prepared in accordance with A2.1.6.4 Radiographic IdentificationEach radiograph shall carry the identification or serial number of the component and viewnumber, when multiple views are taken. Each radiog

25、raph shall also carry the identification of the NDT facility examining thecomponent and the date of the examination. Radiographs of a repair area shall be identified with R1, R2, R3, and so forth, indicatingthe number of times that repairs were attempted. Alternative schemes may be used for identifi

26、cation of repair radiographs so longas each film is clearly identified to relate to a particular repair area. For explosives and propellants, the conditioning temperatureshall be identified on each X-ray film if the ordnance has been conditioned to a temperature other than facility ambient for purpo

27、sesof examination.6.5 Examination and CoverageThe number of parts examined, and the radiographic coverage of each part shall be asspecified by drawings, radiographic techniques, radiographic manuals, handbooks for aircraft technical orders, or otherspecifications, as applicable. Areas to be examined

28、 shall be identified on the drawing by using the symbols in accordance withANSI/AWS A2.4 or other systems of designations that are easily identified on the drawing. If the number of parts to be examinedand the amount of coverage of each part is not specified, all parts shall be examined and shall re

29、ceive 100 % radiographic coverage.6.6 Examination SequenceThe sequence for radiographic examination in the production operation should be specified in themanufacturing or assembly process specification, contract, or purchase order. If not specified, radiographic examination shall beperformed at a st

30、age in the process of manufacturing or assembly at which discontinuities can be detected. Radiographicexamination may be performed before heat treatment, provided liquid penetrant or magnetic particle examinations are performedafter heat treatment.6.7 Nonfilm TechniquesWhen permitted by purchase ord

31、er, contract, or specification, radioscopic examination shall be inaccordance with Practice E1255 and appropriate annex. Qualification of radioscopic systems shall be in accordance with PracticeE1411. Prior approval of the detailed examination, evaluation, and quality control procedures shall be obt

32、ained from the Level IIIradiographer of the cognizant engineering organization (see 5.1.1).6.8 Multi-Film TechniquesFilm techniques with two or more films of the same or different speeds in the same film holder,to be used in either single or superimposed film viewing, shall be permitted provided tha

33、t the applicable radiographic quality level,and film density requirements (see 6.9 and 6.10), are achieved for the area of interest.6.9 Radiographic Quality LevelsThe five quality levels listed in Table 3 may be assigned on the basis of IQI thickness andthe perceptibility of one, two, or three holes

34、 in the hole-type IQI image on the radiograph. If the quality level is not specified onthe drawing or other applicable documents, it shall be Level 2-2T. Unless otherwise specified by the cognizant engineeringorganization, hole-type IQIs used for examination of material 0.25 in. (6.35 mm) or less in

35、 thickness shall be 0.005-in. (0.127-mm)minimum thickness.6.10 Film DensityFor single-film viewing, the film density shall be $1.5 in the area of interest. Where superimposed filmviewing is used, the film density of the superimposed films shall be from 2.0 in the area of interest, and each individua

36、l film shallnot have a film density below 1.0 in the area of interest. Film densities above 4.0 are permitted when agreed upon between thecognizant engineering organization and the NDT facility (see Note 1 of Fig. 1). In no case shall the maximum film density exceed4.5. For single-film viewing, film

37、 densities less than 1.5 are permitted only when items not requiring an IQI (see 6.18) areexamined. The maximum readable film density depends on the film viewer used and its maximum luminance (see 6.27.4). Themaximum readable film density shall always be posted on the viewer.6.11 Processing Radiogra

38、phsRadiographs shall be free from blemishes which may interfere with film interpretation.6.12 IQI SelectionThe IQI thickness shall be based on a thickness not greater than the nominal thickness to be radiographed.For double-wall exposures and double-wall viewing techniques, the IQI shall be based on

39、 the double-wall thickness of theTABLE 3 Quality Levels of ExaminationIQI 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 thickn

40、ess.BExpressed as multiple thickness of IQI.CEquivalent IQI sensitivity 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.E1742/E1742M 117component. The IQI thicknesses that are in betwe

41、en, or smaller than, the thickness increments in Fig. A1.1 (for example, ahole-type IQI that is 0.0025 or 0.006 in. (0.0635 or 0.1524 mm) thick) may be used but are not mandatory. For double-wallexposures and single-wall viewing techniques, the IQI shall be based on the single-wall thickness of the

42、component. In no caseshall the IQI thickness be based on a thickness greater than the thickness to be radiographed. For fabrication welds the IQI shallbe selected in accordance with Annex A2. For explosive/propellants, rocket motors, and their components, IQI selection shall beas specified in accord

43、ance with Annex A3.6.13 Placement of IQIsAn IQI shall be placed on each part radiographed for the duration of exposure, unless a number ofidentical parts are simultaneously exposed on a single film. In such a case, a single IQI shall be placed upon the source side ofa part at the outer edge of the c

44、one of radiation or farthest extremity of the exposure setup (that is, farthest from the radiation beamcenterline). For examination of irregular objects, the IQI shall be placed on the area of the part farthest from the film. The IQIsshall be placed adjacent to the area of interest, since accept/rej

45、ect decisions cannot be made in the area directly beneath the IQI.Where it is not practicable to place the IQI on the part, the separate block technique in 6.13.1, or the film-side technique in 6.13.2,may be used as applicable.6.13.1 Shim, Separate Block, or Like-Section IQI TechniqueWhere it is imp

46、ractical to place the IQI upon the partradiographed, the IQI may be placed on the source side of a separate shim, block, or like section, from the same material groupNOTE 1This figure is a depiction of the abscissa axis: Maximum Allowable Film Density versus ordinate axis: Candela/m2and footlamberts

47、 ingraphical format from tabular data derived from Guide E1390 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

48、 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 10 candela/m2.At levels below this value the eye responds scotopically which means lowercontrast disc

49、rimination 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 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 i