1、Designation: E 1419 09Standard Practice forExamination of Seamless, Gas-Filled, Pressure VesselsUsing Acoustic Emission1This standard is issued under the fixed designation E 1419; 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 () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides guidelines for acoustic emission(AE) examinations of seamless pressure vessels (tubes)
3、 of thetype used for distribution or storage of industrial gases.1.2 This practice requires pressurization to a level greaterthan normal use. Pressurization medium may be gas or liquid.1.3 This practice does not apply to vessels in cryogenicservice.1.4 The AE measurements are used to detect and loca
4、teemission sources. Other nondestructive test (NDT) methodsmust be used to evaluate the significance of AE sources.Procedures for other NDT techniques are beyond the scope ofthis practice. See Note 1.NOTE 1Shear wave, angle beam ultrasonic examination is commonlyused to establish circumferential pos
5、ition and dimensions of flaws thatproduceAE. Time of Flight Diffraction (TOFD), ultrasonic examination isalso commonly used for flaw sizing.1.5 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.6 This standard does not
6、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 and health practices and determine the applica-bility of regulatory limitations prior to use. Specific precau-tionary statements are gi
7、ven in Section 7.2. Referenced Documents2.1 ASTM Standards:2E 543 Specification for Agencies Performing Nondestruc-tive TestingE 650 Guide for Mounting Piezoelectric Acoustic EmissionSensorsE 976 Guide for Determining the Reproducibility ofAcous-tic Emission Sensor ResponseE 1316 Terminology for Non
8、destructive ExaminationsE 2223 Practice for Examination of Seamless, Gas-Filled,Steel Pressure Vessels Using Angle Beam UltrasonicsE 2075 Practice for Verifying the Consistency ofAE-SensorResponse Using an Acrylic RodE 2374 Guide for Acoustic Emission System PerformanceVerification2.2 ASNT Standards
9、:3Recommended Practice SNT-TC-1A for NondestructiveTesting Personnel Qualification and CertificationANSI/ASNT CP-189 Standard for Qualification and Certi-fication of Nondestructive Testing Personnel2.3 Code of Federal Regulations:Section 49, Code of Federal Regulations, Hazardous Mate-rials Regulati
10、ons of the Department of Transportation,Paragraphs 173.34, 173.301, 178.36, 178.37, and 178.4542.5 Compressed Gas Association Standard:Pamphlet C-5 Service Life, Seamless High Pressure Cylin-ders52.4 AIA Document:NAS-410 Certification and Qualification of NondestructiveTesting Personnel63. Terminolo
11、gy3.1 DefinitionsSee Terminology E 1316 for general ter-minology applicable to this practice.3.2 Definitions of Terms Specific to This Standard:3.2.1 fracture critical flawa flaw that is large enough toexhibit unstable growth at service conditions.3.2.2 marked service pressurepressure for which a ve
12、sselis rated. Normally this value is stamped on the vessel.3.2.3 normal fill pressurelevel to which a vessel is pres-surized. This may be greater, or may be less, than markedservice pressure.1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct r
13、esponsibility of Subcommittee E07.04 onAcoustic Emission Method.Current edition approved Feb. 1, 2009. Published February 2009. Originallyapproved in 1991. Last previous edition approved in 2002 as E 1419 02b.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custom
14、er Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available fromAmerican Society for NondestructiveTesting (ASNT), P.O. Box28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.4Availa
15、ble from U.S. Government Printing Office Superintendent of Documents,732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.5Available from Compressed Gas Association (CGA), 4221 Walney Rd., 5thFloor, Chantilly, VA 20151-2923, http:/.6Available from Aerospace Industri
16、es Association of America, Inc. (AIA), 1000Wilson Blvd., Suite 1700,Arlington, VA22209-3928, http:/www.aia-aerospace.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Practice4.1 The AE sensors are mounted on a vessel
17、, and emissionis monitored while the vessel is pressurized above normal fillpressure.4.2 Sensors are mounted at each end of the vessel and areconnected to an acoustic emission signal processor. The signalprocessor uses measured times of arrival of emission bursts todetermine linear location of emiss
18、ion sources. If measuredemission exceeds a prescribed level (that is, specific locationsproduce enough events), then such locations receive secondaryNDT (for example, ultrasonic examination).4.3 Secondary examination establishes presence of flawsand measures flaw dimensions.4.4 If flaw depth exceeds
19、 a prescribed limit (that is, aconservative limit that is based on construction material, wallthickness, fatigue crack growth estimates, and fracture criticalflaw depth calculations), then the vessel must be removed fromservice.5. Significance and Use5.1 Because of safety considerations, regulatory
20、agencies(for example, U.S. Department of Transportation) requireperiodic examinations of vessels used in transportation ofindustrial gases (see Section 49, Code of Federal Regulations).The AE examination has become accepted as an alternative tothe common hydrostatic proof test. In the common hydrost
21、atictest, volumetric expansion of vessels is measured.5.2 An AE examination should not be used for a period ofone year after a common hydrostatic test. See Note 2.NOTE 2The Kaiser effect relates to decreased emission that isexpected during a second pressurization. Common hydrostatic tests use arelat
22、ively high pressure (167 % of normal service pressure). (See Section49, Code of Federal Regulations.) If an AE examination is performed toosoon after such a pressurization, the AE results will be insensitive to alower examination pressure (that is, the lower pressure that is associatedwith an AE exa
23、mination).5.3 Pressurization:5.3.1 General practice in the gas industry is to use lowpressurization rates. This practice promotes safety and reducesequipment investment. The AE examinations should be per-formed with pressurization rates that allow vessel deformationto be in equilibrium with the appl
24、ied load. Typical currentpractice is to use rates that approximate 500 psi/h (3.45MPa/h).5.3.2 Gas compressors heat the pressurizing medium. Afterpressurization, vessel pressure may decay as gas temperatureequilibrates with ambient conditions.5.3.3 Emission from flaws is caused by flaw growth andsec
25、ondary sources (for example, crack surface contact andcontained mill scale). Secondary sources can produce emissionthroughout vessel pressurization.5.3.4 When pressure within a vessel is low, and gas is thepressurizing medium, flow velocities are relatively high. Flow-ing gas (turbulence) and impact
26、 by entrained particles canproduce measurable emission. Considering this, acquisition ofAE data may commence at some pressure greater than startingpressure (for example,13 of maximum examination pressure).5.3.5 Maximum Test PressureSerious flaws usually pro-duce more acoustic emission (that is, more
27、 events, events withhigher peak amplitude) from secondary sources than from flawgrowth. When vessels are pressurized, flaws produce emissionat pressures less than normal fill pressure. A maximum exami-nation pressure that is 10 % greater than normal fill pressureallows measurement of emission from s
28、econdary sources inflaws and from flaw growth.5.3.6 Pressurization SchedulePressurization should pro-ceed at rates that do not produce noise from the pressurizingmedium and that allow vessel deformation to be in equilibriumwith applied load. Pressure holds are not necessary; however,they may be usef
29、ul for reasons other than measurement of AE.5.4 Excess background noise may distort AE data or renderthem useless. Users must be aware of the following commonsources of background noise: high gas-fill rate (measurableflow noise); mechanical contact with the vessel by objects;electromagnetic interfer
30、ence (EMI) and radio frequency inter-ference (RFI) from nearby broadcasting facilities and fromother sources; leaks at pipe or hose connections; and airbornesand particles, insects, or rain drops. This practice should notbe used if background noise cannot be eliminated or controlled.6. Basis of Appl
31、ication6.1 The following items are subject to contractual agree-ment between the parties using or referencing this practice.6.2 Personnel QualificationIf specified in the contractualagreement, personnel performing examinations to this standardshall be qualified in accordance with a nationally or int
32、erna-tionally recognized NDT personnel qualification practice orstandard such asANSI/ASNT-CP-189, SNT-TC-1A, NAS-410,or a similar document and certified by the employer orcertifying agency, as applicable. The practice or standard usedand its applicable revision shall be identified in the contractual
33、agreement between the using parties.6.3 Qualification of Nondestructive AgenciesIf specifiedin the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in Practice E 543. The applicableedition of Practice E 543 shall be specified in the contractualagreement.6.4 Time of Ex
34、aminationThe timing of examination shallbe in accordance with 5.2 unless otherwise specified.6.5 Extent of ExaminationThe extent of examinationincludes the entire pressure vessel unless otherwise specified.6.6 Reporting Criteria/Acceptance CriteriaReporting cri-teria for the examination results shal
35、l be in accordance withSection 11 unless otherwise specified. Since acceptance criteria(for example, reference radiographs) are not specified in thispractice, they shall be specified in the contractual agreement.6.7 Reexamination of Repaired/Reworked ItemsReexamination of repaired/reworked items is
36、not addressed inthis practice and if required shall be specified in the contractualagreement.7. Apparatus7.1 Essential features of the apparatus required for thispractice are provided in Fig. 1. Full specifications are inAnnexA1.E14190927.2 Couplant must be used to acoustically connect sensorsto the
37、 vessel surface. Adhesives that have acceptable acousticproperties, and adhesives used in combination with traditionalcouplants, are acceptable.7.3 Sensors may be held in place with magnets, adhesivetape, or other mechanical means.7.4 The AE sensors are used to detect strain-induced stresswaves prod
38、uced by flaws. Sensors must be held in contact withthe vessel wall to ensure adequate acoustic coupling.7.5 Apreamplifier may be enclosed in the sensor housing orin a separate enclosure. If a separate preamplifier is used, cablelength, between sensor and preamp, must not exceed 6 ft (1.83m).7.6 Powe
39、r/signal cable length (that is, cable betweenpreamp and signal processor) shall not exceed 500 ft (152.4 m).See A1.5.7.7 Signal processors are computerized instruments withindependent channels that filter, measure, and convert analoginformation into digital form for display and permanent stor-age.As
40、ignal processor must have sufficient speed and capacityto independently process data from all sensors simultaneously.The signal processor should provide capability to filter data forreplay. A printer should be used to provide hard copies ofexamination results.7.7.1 A video monitor should display pro
41、cessed examina-tion data in various formats. Display format may be selected bythe equipment operator.7.7.2 A data storage device, such as a floppy disk, may beused to provide data for replay or for archives.7.7.3 Hard copy capability should be available from agraphics/line printer or equivalent devi
42、ce.8. Safety Precautions8.1 As in any pressurization of metal vessels, ambienttemperature should not be below the ductile-brittle transitiontemperature of the pressure vessel construction material.9. Calibration and Standardization9.1 Annual calibration and verification of pressure trans-ducer, AE s
43、ensors, preamplifiers (if applicable), signal proces-sor (particularly the signal processor time reference), and AEelectronic waveform generator should be performed. Equip-ment should be adjusted so that it conforms to equipmentmanufacturers specifications. Instruments used for calibra-tions must ha
44、ve current accuracy certification that is traceableto the National Institute for Standards and Technology (NIST).9.2 Routine electronic evaluation of the signal processorshould be performed monthly and any time there is concernabout signal processor performance. An AE electronic wave-form generator
45、should be used in making evaluations. Eachsignal processor channel must respond with peak amplitudereading within 62 dBV of the electronic waveform generatoroutput.9.3 Routine evaluation of the sensors should be performedmonthly. An accepted procedure for this purpose found inPractice E 2075 and Gui
46、de E 976.9.4 Pre-examination and post-examination, system perfor-mance verification must be conducted immediately before, andimmediately after, each examination. System performanceverification uses a mechanical device to induce stress wavesinto the vessel wall at a specified distance from each senso
47、r.Induced stress waves stimulate a sensor in the same way asemission from a flaw. System performance verification verifiesperformance of the entire system (including sensors, cables,FIG. 1 Essential Features of the Apparatus with Typical Sensor PlacementsE1419093and couplant). Procedures for system
48、performance verificationare found in Guide E 2374.9.4.1 The preferred technique for conducting a systemperformance verification is a pencil lead break (PLB). Leadshould be broken on the vessel surface no less than 4 in. (10.16cm) from the sensor. The 2H lead, 0.3-mm diameter, 3-mmlong should be used
49、 (see Fig. 4 of Guide E 976).9.4.2 Auto Sensor Test (AST).An electromechanical devicesuch as a piezoelectric pulser (and sensor which contains thisfunction) can be used in conjunction with pencil lead break(9.4.1) as a means to assure system performance. This devicecan be used to replace the PLB post examination, systemperformance verification (9.4).10. Procedure10.1 Visually examine accessible exterior surfaces of thevessel. Note observations in examination report.10.2 Isolate vessel to prevent contact with other vessels,hardware, and so forth. Whe
