Designation:E1930/E1930M−12StandardPracticeforExaminationofLiquid-FilledAtmosphericandLow-PressureMetalStorageTanksUsingAcousticEmission1ThisstandardisissuedunderthefixeddesignationE1930/E1930M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thispracticecoversguidelinesforacousticemission(AE)examinationsofnewandin-serviceabovegroundstoragetanksofthetypeusedforstorageofliquids.1.2Thispracticewilldetectacousticemissioninareasofsensorcoveragethatarestressedduringthecourseoftheexamination.Forflat-bottomtankstheseareaswillgenerallyincludethesidewalls(androofifpressureisappliedabovetheliquidlevel).Theexaminationmaynotdetectflawsonthebottomofflat-bottomtanksunlesssensorsarelocatedonthebottom.1.3Thispracticemayrequirethatthetankexperiencealoadthatisgreaterthanthatencounteredinnormaluse.Thenormalcontentsofthetankcanusuallybeusedforapplyingthisload.1.4Thispracticeisnotvalidfortanksthatwillbeoperatedatapressuregreaterthantheexaminationpressure.1.5Itisnotnecessarytodrainorcleanthetankbeforeperformingthisexamination.1.6Thispracticeappliestotanksmadeofcarbonsteel,stainlesssteel,aluminumandothermetals.1.7Thispracticemayalsodetectdefectsintanklinings(forexample,high-bulk,phenolicsandotherbrittlematerials).1.8AEmeasurementsareusedtodetectandlocalizeemis-sionsources.OtherNDTmethodsmaybeusedtoconfirmthenatureandsignificanceoftheAEindications(s).ProceduresforotherNDTtechniquesarebeyondthescopeofthispractice.1.9Examinationliquidmustbeaboveitsfreezingtempera-tureandbelowitsboilingtemperature.1.10Superimposedinternalorexternalpressuresmustnotexceeddesignpressure.1.11Leaksmaybefoundduringthecourseofthisexami-nationbuttheirdetectionisnottheintentionofthispractice.1.12Units—ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedasstandard.Thevaluesstatedineachsyst...
