1、Designation: E215 16Standard Practice forStandardizing Equipment and Electromagnetic Examinationof Seamless Aluminum-Alloy Tube1This standard is issued under the fixed designation E215; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisio
2、n, the year of last revision. A number in parentheses indicates 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 U.S. Department of Defense.1. Scope*1.1 This practice2is
3、 for standardizing eddy current equip-ment employed in the examination of seamless aluminum-alloytube. Artificial discontinuities consisting of flat-bottomed orthrough holes, or both, are employed as the means of standard-izing the eddy current system. General requirements for eddycurrent examinatio
4、n procedures are included.1.2 Procedures for fabrication of reference standards aregiven in Appendixes X1.1 and X2.1.1.3 This practice is intended for the examination of tubularproducts having nominal diameters up to 4 in. 101.6 mm andwall thicknesses up to the standard depth of penetration (SDP)of
5、eddy currents for the particular alloy (conductivity) beingexamined and the examination frequency being used.NOTE 1This practice may also be used for larger diameters or heavierwalls up to the effective depth of penetration (EDP) of eddy currents aslong as adequate resolution is obtained and as spec
6、ified by the using partyor parties.1.4 This practice does not establish acceptance criteria.They must be established by the using party or parties.1.5 The values stated in inch-pound units are to be regardedas the standard.The values given in parentheses are mathemati-cal conversions to SI units tha
7、t are provided for informationonly and are not considered standard.1.6 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
8、plica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive Examinations2.2 Federal Standard:Fed Std. No. 245D Tolerance for Aluminum Alloy andMagnesium Alloy Wroug
9、ht Products42.3 Other Documents:SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing5ANSI/ASNT-CP-189 ASNT Standard for Qualification andCertification of Nondestructive Testing Personnel5NAS-410 NAS Certification and Qualification of Nonde-structive
10、 Personnel (Quality Assurance Committee)62.4 ISO Standards:7ISO 9712 Non-Destructive TestingQualification and Cer-tification of NDT Personnel3. Terminology3.1 DefinitionsFor definitions of terms used in thispractice, refer to Terminology E1316.4. Significance and Use4.1 The examination is performed
11、by passing the tubelengthwise through or near an eddy current sensor energizedwith alternating current of one or more frequencies. Theelectrical impedance of the eddy current sensor is modified by1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the dir
12、ect responsibility of Subcommittee E07.07 onElectromagnetic Method.Current edition approved Dec. 1, 2016. Published January 2017. Originallyapproved in 1963. Last previous edition approved in 2011 as E215 -11. DOI:10.1520/E0215-16.2For ASME Boiler and Pressure Vessel Code applications see related Pr
13、acticeSE-215 in the Code.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 page onthe ASTM website.4Available from Standardization Docu
14、ments Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.5Available fromAmerican Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.6Available from Aerospace Industries
15、 Association of America, Inc. (AIA), 1000Wilson Blvd., Suite 1700,Arlington, VA22209-3928, http:/www.aia-aerospace.org.7Available from International Organization for Standardization (ISO), ISOCentral Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,Geneva, Switzerland, http:/www.is
16、o.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardizatio
17、n established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1the proximity of the tube. The extent of this modification isdetermined by the distance between th
18、e eddy current sensorand the tube, the dimensions, and electrical conductivity of thetube. The presence of metallurgical or mechanical discontinui-ties in the tube will alter the apparent impedance of the eddycurrent sensor. During passage of the tube, the changes in eddycurrent sensor characteristi
19、cs caused by localized differences inthe tube produce electrical signals which are amplified andmodified to actuate either an audio or visual signaling device ora mechanical marker to indicate the position of discontinuitiesin the tube length. Signals can be produced by discontinuitieslocated either
20、 on the external or internal surface of the tube orby discontinuities totally contained within the tube wall.4.2 The depth of penetration of eddy currents in the tubewall is influenced by the conductivity (alloy) of the materialbeing examined and the excitation frequency employed. Asdefined by the s
21、tandard depth of penetration equation, the eddycurrent penetration depth is inversely related to conductivityand excitation frequency (Note 2). Beyond one standard depthof penetration (SDP), the capacity to detect discontinuities byeddy currents is reduced. Electromagnetic examination ofseamless alu
22、minum alloy tube is most effective when the wallthickness does not exceed the SDP or in heavier tube wallswhen discontinuities of interest are within one SDP. The limitfor detecting metallurgical or mechanical discontinuities byway of conventional eddy current sensors is generally acceptedto be appr
23、oximately three times the SDP point and is referredto as the effective depth of penetration (EDP).NOTE 2The standard depth of penetration is defined by the followingequations:SDP 5 503.31fwhere:SDP = one standard depth of penetration, mf = frequency, Hz (cycles per second), and = conductivity, Sieme
24、ns/metre.or:SDP 5 261fwhere:SDP = one standard depth of penetration, inchesf = frequency in Hz (cycles per second), and = conductivity, % IACS.5. Basis of Application5.1 If specified in the contractual agreement, personnelperforming examinations to this practice shall be qualified inaccordance with
25、a nationally recognized NDT personnel quali-fication practice or standard such as ANSI/ASNT-CP-189,SNT-TC-1A, MIL-STD-410, NAS-410, ISO 9712, or a similardocument and certified by the certifying agencys as appli-cable. The practice or standard used and its applicable revisionshall be specified in th
26、e contractual agreement between theusing parties.NOTE 3MIL-STD-410 is canceled and has been replaced withNAS-410, however, it may be used with agreement between contractingparties.5.2 If specified in the contractual agreement, NDT agenciesshall be qualified and evaluated in accordance with Specifica
27、-tion E543. The applicable edition of Specification E543 shallbe specified in the contractual agreement.6. Apparatus6.1 Electronic ApparatusThe electronic apparatus shall becapable of energizing eddy current sensors with alternatingcurrents of suitable frequencies and shall be capable of sensingthe
28、changes in the electromagnetic characteristics of the eddycurrent sensors. Equipment may include a detector, phasediscriminator, filter circuits, gating circuits, and signalingdevices as required for the particular application.6.2 Eddy Current SensorsEddy current sensors shall becapable of inducing
29、currents in the tube and sensing changes inthe electrical characteristics of the tube. The eddy currentsensors may be of the encircling coil (annular) type or surfaceprobe type.7. Standardization of Apparatus7.1 The apparatus shall be adjusted with an appropriatereference standard to ensure that the
30、 equipment is operating atthe proper level of sensitivity, with the following consider-ations:7.1.1 Primary reference standards employed for this pur-pose shall be prepared in accordance with the methods de-scribed in Appendix X1.1.7.1.2 Equivalent secondary reference standards, prepared inaccordanc
31、e with methods described in Appendix X2.1, alsomay be employed for standardizing the apparatus.7.1.3 Reference standards normally are of the same alloy,temper, and dimensions as the tube to be examined.7.1.4 Examinations shall not be conducted unless the equip-ment can be set to the levels required
32、by this standardizationprocedure.7.1.5 For practical applications, reference standards alsomay be employed to establish quality control levels.8. Procedure8.1 Standardize the examination instrument using the ap-propriate reference standard prior to examination and check atleast every 4 h during cont
33、inuous operation, or wheneverimproper functioning of the examination apparatus is sus-pected. If improper functioning occurs, restandardize theapparatus in accordance with Section 7, and reexamine alltubes examined since the last successful standardization.8.2 Tubes may be examined in the final draw
34、n, annealed, orheat-treated temper, or in the drawn temper prior to the finalanneal or heat treatment.8.3 The length of tube over which end effect is significantmay be determined by placing a series of holes or notches inspecial reference tubes and determining the distance from thetube end at which
35、the signal amplitude from the discontinuitiesbegins to decrease.8.3.1 When standardizing and testing using secondary stan-dard Method B (X2.5.2), if full length testing is required, theE215 162tube must be ordered to be electromagnetic tested in a roughcut length and have the untested 7 in. (175 mm)
36、 removed fromeach end.NOTE 4There is an area near each end which cannot be tested eitherbecause of an alarm from end effect or because end suppression is used toeliminate an alarm from end effect. Up to 7 in. (175 mm) on each end isto be considered untested, regardless of the standard used. Customer
37、s mustspecify if they want these untested areas removed.9. Application9.1 This application covers the electromagnetic examinationof aluminum-alloy seamless tube using primary and secondaryreference standards.9.2 Primary and secondary reference standards, described inAppendixes X1.1 and X2.1, respect
38、ively, when used as accep-tance standards, will establish probable detection of defectsthat are of a severity likely to cause leaks or substantialweakening of the tube.9.3 Using electronic apparatus and eddy current sensorsdescribed in Section 6, the equipment sensitivity shall bestandardized in acc
39、ordance with Section 7 under the followingexamination conditions:9.3.1 FrequencyThe frequency shall be in the range from1 to 125 kHz. The examination frequency should be adjusted toprovide optimum penetration of the tube wall or to placediscontinuities of interest within one SDP. Discontinuitiesloca
40、ted deeper than the SDP point will be detected with lesssensitivity. The SDP point will vary as a function of the tubealloy (conductivity) and examination frequency and may bedetermined by the depth of penetration equation given inSection 4, Note 2.9.3.2 Speed of ExaminationThe examination rate, ors
41、peed of the tube with respect to the eddy current sensor, mayvary with the application. In encircling coil applications,examination speeds of 50 ft/min (15 m/min) to 500 ft/min (150m/min) are recommended where possible, but examinationspeeds as high as 1000 ft/min (300 m/min) are permissible. Insurf
42、ace probe applications, examination speeds are inherentlyslower due to reduced surface coverage and the necessity torotate the eddy current sensor or the tube to produce a helicalscan. All instrument adjustments, that is, frequency, phasesetting, filter setting, sensitivity setting, threshold-level
43、setting,etc., shall be made with the reference standard or acceptancestandard or both passing through or by the eddy current sensorat the same speed at which the examination of tube is to beconducted.9.3.3 Phase SettingThe phase setting should be selectedto provide the best signal-to-noise ratio for
44、 the referencestandard employed, that is, the maximum ratio of indicationheight from the appropriate artificial discontinuities to theindication height from non-detrimental discontinuities.9.3.4 Filter SettingThe filter setting should be selectedcommensurate with the examination speed to provide opt
45、imumfiltering of non-detrimental, time-varying discontinuities suchas geometry, pathline variation, high-frequency noise, etc.9.3.5 Sensitivity SettingThe sensitivity setting shall beadjusted to provide clearly discernible indications of a conve-nient height for the appropriate accept holes (A or da
46、), but itshall not be high enough to cause off-scale or saturatedindications for the appropriate reject holes (2A or db)ofthereference standard.9.3.6 Threshold-Level SettingThe threshold-level setting(reject level) shall be adjusted to automatically trigger an audioor visual-signaling device or a me
47、chanical marker when theappropriate artificial discontinuity (or discontinuities) of theacceptance standard passes through or by the eddy currentsensor.9.4 Using Reference Standards as Acceptance Standards:9.4.1 Method A (X2.1) Reference Standards: When usingreference standards as acceptance standar
48、ds the threshold levelshould be adjusted to accept tubes exhibiting eddy currentresponses smaller than those obtained from the appropriatereject holes (2A or db) and to reject those with responsesequivalent to or greater than those obtained from the appropri-ate reject holes (2A or db) in the refere
49、nce standard. Experienceshows that this procedure will aid in the rejection of severedefects and, at the same time, minimize erroneous rejection oftubes that might exhibit noise from non-detrimental disconti-nuities.9.4.2 Method B (X2.2) Reference Standard Selection: Ref-erence standards selected for use must be the same alloy,temper, diameter, and wall thickness as the material beingtested. The reference standard selected for use must contain theproper size reject holes and must have been fabricated andidentified in accordance with this procedure.9.4.2.1 Wh
