1、Designation: E 2023 99 (Reapproved 2004)Standard Practice forFabrication of Neutron Radiographic Sensitivity Indicators1This standard is issued under the fixed designation E 2023; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the fabrication of Sensitivity Indi-cators (SI), which can be used to determine the rel
3、ative qualityof radiographic images produced by direct, thermal neutronradiographic examination.1.2 The values stated in inch-pound units are regarded to bestandard. The SI equivalents given in brackets in the text arefor information only.1.3 This standard does not purport to address all of thesafet
4、y 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 prior to use.2. Referenced Documents2.1 ASTM Standards:2E 543 Practice for Evaluating Age
5、ncies Performing Nonde-structive TestingE 545 Method for Determining Image Quality in DirectThermal Neutron Radiographic ExaminationE 748 Practices for Thermal Neutron Radiography of Ma-terialsE 1316 Terminology for Nondestructive Examinations3. Terminology3.1 DefinitionsFor definitions of terms use
6、d in this prac-tice, see Terminology E 1316, Section H.4. Summary of Practice4.1 The Sensitivity Indicator (SI) is used for qualitativedetermination of the sensitivity of detail visible on the neutronradiograph. It consists of a step wedge containing gaps andholes of known dimensions. Visual inspect
7、ion of the image ofthis device provides subjective information regarding totalradiographic sensitivity with respect to the step-block material,as well as optional subjective data, regarding detrimental levelsof gamma exposure.4.2 Neutron radiography practices are discussed in PracticesE 748. The neu
8、tron radiograph used to determine image qualityusing the SI shall meet the requirements of Method E 545.5. Significance and Use5.1 The only truly valid image quality indicator is a materialor component, equivalent to the part being neutron radio-graphed, with a known standard discontinuity, inclusio
9、n, omis-sion or flaw (reference standard comparison part). The SI isdesigned to substitute for the reference standard, providingqualitative information on hole and gap sensitivity in a singleunit. Fabrication in accordance with this practice is vital foraccurate and consistent measurements.5.2 This
10、practice shall be followed for the fabrication of allSIs to be used with Method E 545 to determine image qualityin direct thermal neutron radiography.6. Basis of Application6.1 Qualification of Nondestructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evalua
11、ted as described in Practice E 543. The applicableedition of Practice E 543 shall be specified in the contractualagreement.6.2 Procedures and TechniquesThe procedures and tech-niques to be utilized shall be as described in this practice unlessotherwise specified. Specific techniques may be specified
12、 in thecontractual agreement.6.3 Reporting Criteria/Acceptance CriteriaReporting cri-teria for the examination results shall be in accordance withSections 9 and 10 unless otherwise specified. Acceptancecriteria, for example, reference radiographs, shall be specifiedin the contractual agreement.6.4 R
13、eexamination of repaired/reworked items is not ad-dressed in this practice and, if required, shall be specified in thecontractual document.1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.05 onRadiology (Ne
14、utron) Method.Current edition approved May 1, 2004. Published June 2004. Originallyapproved in 1999. Last previous edition approved in 1999 as E 2023 - 99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM
15、Standards 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.7. Sensitivity Indicator (SI)7.1 The Sensitivity Indicator (SI) shall be constructed ofcast
16、 acrylic resin, lead (optional), and aluminum. The construc-tion and dimensions are shown in Fig. 1.7.2 The optional lead step in the SI may be replaced with ablank, cast acrylic resin step. The lead provides a visualindication of beam gamma content; however, the lead image isnot used for any of the
17、 SI calculations of Method E 545.7.3 The acrylic resin shall be methylmethacrylate.7.4 All dimensional tolerances are as noted on the figures.7.5 Aluminum shims and strips shall be 99.9 % pure el-emental material.7.6 The SI may be encased in a 6061 aluminum dust cover,0.012-in. 0.305-mm thick.7.7 Wh
18、en used, the optional lead shim shall be at least99.9 % pure elemental material.8. Fabrication38.1 Components:8.1.1 Mill a Channel, 0.850-in. (21.6-mm) wide by 6.5-in.165-mm long from an aluminum block, 1-in. 25.4-mm wideby at least 0.303-in. 7.70-mm high by 6.5-in. 165-mm long.The channel should be
19、gin 0.075-in. 1.90-mm from edge Aand leave 0.103-in. 2.62-cm aluminum in the bottom of thechannel (see Fig. 2).8.1.2 Mill the A Channel (see Fig. 1), within this channel,0.125-in. 3.18-mm wide by 0.005-in. 0.127-mm deep by6.5-in. 165-mm long. The near edge of channel A should be0.450-in. 11.4-mm fro
20、m edge A (see Fig. 3).8.1.3 Mill the B Channel, adjacent to the A channel,0.125-in. 3.18-mm wide by 0.010-in. 0.254-mm deep by6.5-in. 165-mm long. The near edge of channel B should be0.325-in. 8.26-mm from edge A (see Fig. 3).8.1.4 Mill the C Channel, adjacent to the B channel,0.125-in. 3.18-mm wide
21、 by 0.020-in. 0.508-mm deep by6.5-in. 165-mm long. The near edge of channel C should be0.200 in. 5.08 mm from edge A (see Fig. 3).8.1.5 OptionalMill the D channel adjacent to the Cchannel, 0.125-in. 3.18-mm wide by 0.010-in. 0.254-mmdeep by 6.5-in. 165-mm long. The near edge of channel Dshould be 0.
22、075-in. 1.90-mm from edge A.3The instructions in Section 8 assume the simultaneous fabrication of five unitsfor practical reasons. Units may be fabricated singly, if desired.Material MethylmethacrylateShim Thickness Hole DiameterA 0.005 0.005B 0.010 0.010C 0.020 0.020D 0.010 0.010NOTE 1All dimension
23、s are in inches.NOTE 2The lead step may be replaced with a methylmethacrylate strip with the D shim eliminated.FIG. 1 Sensitivity IndicatorE 2023 99 (2004)2NOTE 1Unless otherwise specified, use the following:Dimensions are in inches.Tolerances on machined dimensions: .XX = 6 .01 .XXX = 6 .002.FIG. 2
24、 Main Channel in Aluminum BlockNOTE 1Unless otherwise specified, use the following:Dimensions are in inches.Tolerances on machined dimensions: .XX = 6 .01 .XXX = 6 .002.FIG. 3 Channels A Through D in Main ChannelE 2023 99 (2004)3NOTE 1The D channel is not required and shall not be milled if thelead
25、shim is not to be used.8.1.6 Prepare five methylmethacrylate strips, 0.060-in.1.52-mm thick by at least 0.200-in. 5.08-mm wide by6.5-in. 165-mm long. These strips will be used in 8.2.11.8.1.7 Prepare four methylmethacrylate strips, 0.125-in.3.18-mm thick by at least 0.200-in. 5.08-mm wide by6.5-in.
26、165-mm long. One of the methylmethacrylate stripsmay be replaced with an optional lead strip of the samedimensions. These strips will be used in 8.2.5.8.1.8 Prepare one each strip from aluminum shim stock, atleast 0.200-in. 5.08-mm wide by 6.5-in. 165-mm long, withthe following thickness:0.0005 in.
27、0.0127 mm0.0010 in. 0.0254 mm0.0020 in. 0.0508 mm0.0030 in. 0.0762 mm0.0040 in. 0.102 mm0.0050 in. 0.127 mm0.0100 in. 0.254 mm8.1.9 Prepare one each methylmethacrylate strip to fitsnugly in the 0.125-in. 3.18-mm wide by 6.5-in. 165-mmlong with the following thickness:0.0050 in. 0.127 mm (Shim A)0.01
28、00 in. 0.254 mm (Shim B)0.0200 in. 0.508 mm (Shim C)0.0100 in. 0.254 mm (Shim D) (If used, this strip is to be fab-ricated from lead stock (see Fig. 4). These strips will becomeShim A through Shim D in 8.1.10.)8.1.10 Drill four holes in the shims from 8.1.9, starting0.218 in. 5.54 mm from one end an
29、d centering the other threeholes 0.215 in. 5.46 mm from the first hole. Repeat theprocess along the rest of the 6.5-in. 165-mm length (see Fig.4). The diameter of the holes are as follows:Shim A 0.005-in. 0.127-mm diameterShim B 0.010-in. 0.254-mm diameterShim C 0.020-in. 0.508-mm diameterShim D 0.0
30、10-in. 0.254-mm diameter, if optional Shim D is tobe used.To verify that the various shims have the proper holes drilledinto them, a certified hole measurement report is required.8.1.11 To keep the SI intact during use, it is highly recom-mended that a dust cover be kept on the unit. One dust coverf
31、or each SI may be prepared from aluminum shim stock,0.012-in. 0.305-mm thick by 1.50-in.238.1-mm2 by cuttingout a 0.250-in.26.35-mm2 from each corner and folding thealuminum to form a cover, 1-in.225.4-mm2 by 0.250-in.6.35-mm high (see Fig. 1).8.2 Assembly:8.2.1 Insert Shim C into the C channel mill
32、ed in 8.1.4 (seeFig. 5).8.2.2 Insert Shim B into the adjacent B channel milled in8.1.3 (see Fig. 5).8.2.3 Insert Shim A into the adjacent A channel milled in8.1.2 (see Fig. 5).8.2.4 If the D channel was milled in 8.1.5, insert the leadshim (see Fig. 5).8.2.5 Insert a 0.125-in. 3.18-mm methylmethacry
33、late strip(previously prepared in 8.1.7) into the channel so that thesecond strip is positioned over Shim C. Over Channel D, inserteither the optional lead strip or a 0.125-in. 3.18-mm methyl-methacrylate strip (see Fig. 6).8.2.6 Insert the 0.010-in. 0.254-mm thick aluminum stripnext to the methylme
34、thacrylate strip between the B and Cchannels (see Fig. 6).8.2.7 Insert another 0.125-in. 3.18-mm methylmethacry-late strip next to the aluminum strip (see Fig. 6).8.2.8 Insert the 0.005-in. 0.127-mm thick aluminum strip(see Fig. 6).8.2.9 Insert the last 0.125-in. 3.18-mm methylmethacry-late strip ne
35、xt to the previously inserted aluminum strip (seeFig. 6).8.2.10 Insert the 0.0005-in. 0.0127-mm thick aluminumstrip next to the previously inserted methylmethacrylate strip(see Fig. 6).Shim Thickness Hole DiameterA 0.0050 0.0050B 0.0100 0.0100C 0.0200 0.0200D 0.0100 0.0100FIG. 4 ShimsE 2023 99 (2004
36、)48.2.11 Insert a 0.060-in. 1.52-mm thick methylmethacry-late strip next to the previously inserted aluminum strip (seeFig. 6).8.2.12 Repeat the steps described in 8.2.10 and 8.2.11,alternating increasing aluminum strip thickness with 0.060-in.1.52-mm thick methylmethacrylate strips (see Fig. 6), th
37、at is:0.001-in. 0.0254-mm thick aluminum strip0.060-in. 1.52-mm thick methylmethacrylate strip0.002-in. 0.0508-mm thick aluminum strip0.060-in. 1.52-mm thick methylmethacrylate strip0.003-in. 0.0762-mm thick aluminum strip0.060-in. 1.52-mm thick methylmethacrylate strip0.004-in. 0.102-mm thick alumi
38、num strip0.060-in. 1.52-mm thick methylmethacrylate strip8.2.13 Cut and insert aluminum shims sized as required fora tight fit between the last 0.060-in. 1.52-mm methyl-methacrylate strip and the wall of the channel to wedge all thestrips in place (this step is important for later machining of theun
39、it) (see Fig. 6).8.3 Fabrication:8.3.1 Mill off a 1.0-in. 25.4-mm long section of thestacked channel from the 6.5-in. 165-mm length.NOTE 1See Fig. 4.FIG. 5 Shims in ChannelsUnless otherwise specified, use the following:Dimensions are in inches.Tolerances on machined dimensions: .XX = 6 .01 .XXX = 6
40、.002.FIG. 6 Strips in Main ChannelE 2023 99 (2004)58.3.2 Mill the top surface of the sectioned unit to a height of0.303 in. 7.70 mm. This height is equivalent to the first stepof 0.200 in. 5.08 mm of methylmethacrylate (see Fig. 7).8.3.3 Mill a 0.215-in. 5.46-mm wide channel, 0.230-in.5.84-mm from E
41、dge B (as shown in Fig. 7) across the fullwidth of the stacked assembly, including the aluminum walls.The bottom of the channel should be 0.203 in. 5.16 mm fromthe bottom of the block.8.3.4 Mill another 0.215-in. 5.46-mm wide channel,0.445-in. 11.30-mm from Edge B (as shown in Fig. 8) acrossthe full
42、 width of the stacked assembly, including the aluminumwalls. The bottom of the channel should be 0.153 in. 3.89 mmfrom the bottom of the block.8.3.5 Finish milling all stock between the aluminum wallsfrom the last channel to Surface C to a height of 0.153 in. 3.89mm from the bottom of the block, as
43、shown in Fig. 7.Donotremove material from the aluminum walls. After completion,the block should look as shown in Fig. 8.8.3.6 Mill the final 0.215-in. 5.46-mm wide channel,0.660-in. 16.76-mm from Edge B, including the aluminumwalls. The bottom of the channel should be 0.128 in. 3.25 mmfrom the botto
44、m of the block (see Fig. 9).8.3.7 Machine a base in the completed unit by cutting 0.015in. 0.381 mm from all four sides. The machining should leavea 0.080-in. 2.03-mm thick base (see Fig. 9).8.3.8 The SI is complete and should look identical to the SIshown in Fig. 1.8.3.9 Slip-fit the dust cover fro
45、m 8.1.11. Do not use glue.9. Certification9.1 Upon request of the purchaser by contract or purchaseorder, any fabricator of the SI described in this practice shallprovide materials certification. To verify the details of con-struction, a measurement certification of individual compo-nents and assemb
46、ly to verify correct location and sizes and acomparison thermal neutron radiograph of the assembled SIwith that of a reference standard SI (preferably on a singleneutron radiograph) shall be provided.9.2 All dimensions should be measured with a micrometeror an optical comparator to determine the SI
47、dimensions.9.3 The comparison thermal neutron radiograph of theassembled SI, along with a reference standard SI, shall showthe following:9.3.1 All shims and strips are in place and aluminum stripsare vertical (no blurred edges).9.3.2 A minimum of six or seven holes should be visible,identical to tho
48、se in the reference SI.9.3.3 Using a magnifier with a calibrated scale, measure thesize of the gaps and visible holes. If the measured dimensionsmatch those in the reference standard SIs image, the unit(s)are acceptable and can be certified.9.4 The comparison thermal neutron radiograph of theassembl
49、ed SI with the reference standard SI shall meet qualitylevel Category I, specified in the latest edition of MethodE 545.9.5 Any SI certified under Method E 54581, 86, or 91 isassumed to be a reference SI, unless there is known to be adisqualifying deficiency.10. Records10.1 Complete records of the fabrication details shall bemaintained by the manufacturing facility for three years or as
