1、Designation: E1930/E1930M 17Standard Practice forExamination of Liquid-Filled Atmospheric and Low-PressureMetal Storage Tanks Using Acoustic Emission1This standard is issued under the fixed designation E1930/E1930M; the number immediately following the designation indicates the yearof original adopt
2、ion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers guidelines for acoustic emission(AE) examinations o
3、f new and in-service aboveground storagetanks of the type used for storage of liquids.1.2 This practice will detect acoustic emission in areas ofsensor coverage that are stressed during the course of theexamination. For flat-bottom tanks these areas will generallyinclude the sidewalls (and roof if p
4、ressure is applied above theliquid level). The examination may not detect flaws on thebottom of flat-bottom tanks unless sensors are located on thebottom.1.3 This practice may require that the tank experience a loadthat is greater than that encountered in normal use. The normalcontents of the tank c
5、an usually be used for applying this load.1.4 This practice is not valid for tanks that will be operatedat a pressure greater than the examination pressure.1.5 It is not necessary to drain or clean the tank beforeperforming this examination.1.6 This practice applies to tanks made of carbon steel,sta
6、inless steel, aluminum and other metals.1.7 This practice may also detect defects in tank linings (forexample, high-bulk, phenolics and other brittle materials).1.8 AE measurements are used to detect and localize emis-sion sources. Other NDT methods may be used to confirm thenature and significance
7、of the AE indications (s). Proceduresfor other NDT techniques are beyond the scope of this practice.1.9 Examination liquid must be above its freezing tempera-ture and below its boiling temperature.1.10 Superimposed internal or external pressures must notexceed design pressure.1.11 Leaks may be found
8、 during the course of this exami-nation but their detection is not the intention of this practice.1.12 UnitsThe values stated in either SI units or inch-pound units are to be regarded as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used indep
9、endently of the other. Combiningvalues from the two systems may result in non-conformancewith the standards.1.13 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 appro-priate safety
10、 and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are given in Section 8.1.14 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Dec
11、ision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E543 Specification for Agencies Performing NondestructiveTestingE650 Guide for M
12、ounting Piezoelectric Acoustic EmissionSensorsE976 Guide for Determining the Reproducibility ofAcousticEmission Sensor ResponseE1106 Test Method for Primary Calibration of AcousticEmission SensorsE1316 Terminology for Nondestructive ExaminationsE1781 Practice for Secondary Calibration of Acoustic Em
13、is-sion Sensors1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.04 onAcoustic Emission Method.Current edition approved June 1, 2017. Published June 2017. Originallyapproved in 1997. Last previous edition ap
14、proved in 2012 as E1930 - 12. DOI:10.1520/E1930_E1930M-17.2For 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.*A
15、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 standardization establi
16、shed 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.1E2374 Guide for Acoustic Emission System PerformanceVerification2.2 ANSI/ASNT Standard:Recommended Practice
17、ASNT SNT-TC-1A for Qualificationand Certification of Nondestructive Testing Personnel3ANSI/ASNT CP-189 Standard for Qualification and Certifi-cation of NDT Personnel32.3 ASME Standard:Section V, Article 12, Boiler & Pressure Vessel Code42.4 AIA Document:NAS-410 Certification and Qualification of Non
18、destructiveTesting Personnel52.5 ISO Standard:6ISO 9712 Non-Destructive Testing: Qualification and Certi-fication of NDT Personnel3. Terminology3.1 Definitions:3.1.1 This practice makes use of definitions provided inTerminology E1316. Definitions for terms that do not appear inTerminology E1316 are
19、given below.3.2 Definitions of Terms Specific to This Standard:3.2.1 AE activitythe presence of acoustic emission duringan examination. It is normally measured by one or more AEparameters such as number of hits, events, signal strength orAE counts. A source is considered active if its AE activitycon
20、sistently increases with increasing load.3.2.2 maximum operating pressurelargest pressure withinthe tank during the six-month period prior to AE examination.This pressure involves the maximum liquid contents level, therange of temperature experienced during operation, superim-posed hydrostatic or pn
21、eumatic pressure, or both, and anyoverload or upset conditions which may have occurred.3.2.3 signal strengththe measured area of the rectified AEsignal.4. Summary of Practice4.1 GeneralThis practice consists of subjecting storagetanks to increasing stress while monitoring with sensors thatare sensit
22、ive to acoustic emission (transient stress waves)caused by growing flaws. The instrumentation and techniquesfor sensing and analyzing AE are described herein.4.2 LoadingThis practice requires stressing the tank.Stressing can be accomplished by filling the tank with itsnormal contents or with an alte
23、rnative liquid and in some casesapplying a superimposed hydrostatic or pneumatic pressure, orboth.4.3 ReportThe report documents results of the AE exami-nation and other important information. The report also pro-vides recommendations for follow-up NDT examinations atspecific locations.5. Significan
24、ce and Use5.1 GeneralThis procedure is used for evaluation of thestructural integrity of atmospheric storage tanks. The AEmethod can detect flaws which are in locations that are stressedduring pressurization. Such locations include the tank wall,welds attaching pads to the tank, nozzle attachments,
25、and weldsattaching circumferential stiffeners to the tank. Among thepotential sources of acoustic emission are:5.1.1 In both parent metal and weld associated regions:5.1.1.1 Cracks,5.1.1.2 The effect of corrosion, including cracking of cor-rosion products or local yielding,5.1.1.3 Stress corrosion c
26、racking,5.1.1.4 Certain physical changes, including yielding anddislocations,5.1.1.5 Embrittlement, and5.1.1.6 Pits and gouges.5.1.2 In weld associated regions:5.1.2.1 Incomplete fusion,5.1.2.2 Lack of penetration,5.1.2.3 Undercuts, and5.1.2.4 Voids and porosity.5.1.2.5 Inclusions:5.1.2.6 Contaminat
27、ion.5.1.3 In parent metal:5.1.3.1 Laminations.5.1.4 In brittle linings:5.1.4.1 Cracks,5.1.4.2 Chips, and5.1.4.3 Inclusions.NOTE 1Not all of these sources are typically encountered in fieldexamination, some are detected under laboratory conditions.5.2 Accuracy of the results from this practice can be
28、influenced by factors related to setup and calibration ofinstrumentation, background noise, material properties andcharacteristics of an examined structure.5.3 The outcome of this practice is to determine if the tankis suitable for service or if follow-up NDT is needed before thatdetermination can b
29、e made.5.4 Unstressed AreasFlaws in unstressed areas and pas-sive flaws (those that are structurally insignificant under theapplied load) will not generate AE. Such locations can includethe roof and certain welds associated with platforms, ladders,and stairways.5.5 Passive Flaws (in Stressed Areas)S
30、ome flaws instressed areas might not generate acoustic emission duringstressing. This usually means that the flaw has a higher stresstolerance than the examination stress.5.6 FillingFilling proceeds at rates which minimize AEactivity caused by fluid flow and which allow vessel deforma-tion to be in
31、equilibrium with applied load. Hold periods are3Available fromAmerican Society for Nondestructive Testing (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.4Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park
32、 Ave., New York, NY 10016-5990, http:/www.asme.org.5Available from Aerospace Industries Association of America, Inc. (AIA), 1000Wilson Blvd., Suite 1700,Arlington, VA22209-3928, http:/www.aia-aerospace.org.6Available from International Organization for Standardization (ISO), ISOCentral Secretariat,
33、BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,Geneva, Switzerland, http:/www.iso.org.E1930/E1930M 172used throughout the filling schedule to evaluate AE activityproduced by the loaded structure in the absence of fill noise.5.7 Follow-upSources detected by AE should be exam-ined using other N
34、DT methods.5.8 Background NoiseExcess background noise may dis-tort AE data or render them useless. Users must be aware ofcommon sources of background noise: high fill rate (measur-able flow noise), mechanical contact (impact, friction, fretting)with the tank by objects, electromagnetic interference
35、 (EMI)(motors, welders, overhead cranes) and radio frequency inter-ference (RFI) (broadcasting facilities, walkie talkies), leaks atpipe or hose connections, leaks in the tank bottom or walls,airborne particles, insects, or rain drops, heaters, spargers,agitators, level detectors and other component
36、s inside the tank,chemical reactions occurring inside the tank, and hydrody-namic movement of gas bubbles. This practice should not beused if background noise cannot be eliminated or controlled.6. Basis of Application:6.1 The following items are subject to contractual agree-ment between the parties
37、using or referencing this practice.6.2 Personnel Qualifications6.2.1 If specified in the contractual agreement, personnelperforming examinations to this standard shall be qualified inaccordance with a nationally or internationally recognizedNDT personnel qualification practice or standard such asANS
38、I/ASNT-CP-189, SNT-TC-1A, NAS-410, ISO 9712, or asimilar document and certified by the employer or certifyingagency, as applicable. The practice or standard used and itsapplicable revision shall be identified in the contractual agree-ment between the using parties.6.2.2 Training and ExaminationIn ad
39、dition, it is requiredthat personnel performing acoustic emission examination ofstorage tanks attend a dedicated training course on the subjectand pass a written examination. The training course shallinclude the following topics:6.2.2.1 Storage tank construction and terminology,6.2.2.2 Failure mecha
40、nisms of metal and metal fabricatedsystems,6.2.2.3 Case histories of metal vessels examined withacoustic emission,6.2.2.4 Storage tank examination procedures, includingloading requirements,6.2.2.5 Data collection and interpretation, and6.2.2.6 Examination report and permanent record require-ments.6.
41、3 Qualification of Nondestructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in Practice E543. The applicableedition of Practice E543 shall be specified in the contractualagreement.6.4 Timing of ExaminationThis practice may be used onn
42、ew tanks, erected, in place or tanks that have been in service.6.5 Extent of ExaminationThe extent of examination shallbe in accordance with 1.2, 1.6, 1.7 and 1.11 unless otherwisespecified.6.6 Reporting Criteria/Acceptance CriteriaReporting cri-teria for the examination results shall be in accordan
43、ce with10.11 unless otherwise specified.6.6.1 Non-mandatory acceptance criteria are described inAppendix X2.6.7 Reexamination of Repaired/Reworked ItemsReexamination of repaired/reworked items is not addressed inthis standard and if required shall be specified in the contrac-tual agreement.7. Appara
44、tus7.1 Essential features of the apparatus required for thisexamination method are provided in Fig. 1. Full specificationsare in Annex A1.7.2 AE sensors are used to detect stress waves produced byflaws. Sensors must be held in contact with the vessel wall toensure adequate acoustic coupling. Sensors
45、 may be held inplace with magnets, adhesive tape, or other mechanical means.7.3 A preamplifier may be enclosed in the sensor housing orin a separate enclosure. If a separate preamplifier is used, cablelength between sensor and preamplifier should not exceed 2 m6 ft. Longer cables may cause unaccepta
46、ble signal attenuationand increase the likelihood of EMI and RFI.7.4 Signal cable length (that is, cable between preamplifierand signal processor) should not exceed 150 m 500 ft. Forlonger cable lengths signal repeaters may be required tominimize signal attenuation.7.5 Signals shall be processed wit
47、h computerized systemswith independent channels that filter, measure, and convertanalog information into digital form for display and permanentstorage. A signal processor must have sufficient speed andcapacity to process data independently from all sensors simul-taneously. A printer should be used t
48、o provide hard copies ofexamination results.7.6 A video monitor should display processed data invarious formats. Display format may be selected by theequipment operator.7.7 A data storage device, such as a hard drive, may be usedto provide data for replay or for archives.7.8 Hard copy capability sho
49、uld be available from a graph-ics printer or equivalent device.8. Safety Precautions8.1 Ambient temperature should not be below the ductile-brittle transition temperature of the pressure vessel construc-tion material.9. Calibration and Verification9.1 Annual calibration of AE sensors, preamplifiers, signalprocessor and AE electronic signal simulators shall be per-formed. Equipment should be adjusted so that it conforms toequipment manufacturers specifications. Instruments used forstandardizations must have current accuracy certification that istr
