【英文标准名称】:StandardPracticeforComputedTomographic(CT)ExaminationofCastings
【原文标准名称】:涂层的计算机层析摄影(CT)检查的标准实施规范
【标准号】:ASTME1814-1996(2007)
【标准状态】:现行
【国别】:
【发布日期】:1996
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E07.01
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:castings;computedtomography;CT;examination;NDE;nondestructiveevaluation;nondestructiveexamination
【摘要】:CTmaybeperformedonanobjectwhenitisintheas-cast,intermediate,orfinalmachinedcondition.ACTexaminationcanbeusedasadesigntooltoimprovewaxformsandmoldings,establishprocessparameters,randomlycheckprocesscontrol,performfinalqualitycontrol(QC)examinationfortheacceptanceorrejectionofparts,andanalyzefailuresandextendcomponentlifetimes.ThemostcommonapplicationsofCTforcastingsareforthefollowing:locatingandcharacterizingdiscontinuities,suchasporosity,inclusions,cracks,andshrink;measuringas-castpartdimensionsforcomparisonwithdesigndimensions;andextractingdimensionalmeasurementsforreverseengineering.TheextenttowhichaCTimagereproducesanobjectorafeaturewithinanobjectisdictatedlargelybythecompetinginfluencesofspatialresolution,contrastdiscrimination,andartifactsoftheimagingsystem.Operatingparametersstrikeanoverallbalancebetweenimagequality,examinationtime,andcost.ArtifactsareoftenthelimitingfactorinCTimagequality.(SeePracticeE1570foranin-depthdiscussionofartifacts.)Artifactsarereproduciblefeaturesinanimagethatarenotrelatedtoactualfeaturesintheobject.Artifactscanbeconsideredcorrelatednoisebecausetheyformrepeatablefixedpatternsundergivenconditionsyetcarrynoobjectinformation.Forcastings,itisimperativetorecognizewhatisandisnotanartifactsinceanartifactcanobscureormasqueradeasadiscontinuity.Artifactsaremostprevalentincastingswithlongstraightedgesorcomplexgeometries,orboth.1.1Thispracticecoversauniformprocedurefortheexaminationofcastingsbythecomputedtomography(CT)technique.TherequirementsexpressedinthispracticeareintendedtocontrolthequalityofthenondestructiveexaminationbyCTandarenotintendedforcontrollingtheacceptabilityorqualityofthecastings.Thispracticeimplicitlysuggeststheuseofpenetratingradiation,specificallyXraysandgammarays.1.2ThispracticeprovidesauniformprocedureforaCTexaminationofcastingsforoneormoreofthefollowingpurposes:1.2.1Examiningfordiscontinuities,suchasporosity,inclusions,cracks,andshrink;1.2.2Performingmetrologicalmeasurementsanddeterminingdimensionalconformance;and1.2.3Determiningreverseengineeringdata,thatis,creatingcomputer-aideddesign(CAD)datafiles.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.Forspecificsafetystatements,seeSection7,NBSHandbook114,and21CFR1020.40and29CFR1910.96.
【中国标准分类号】:G50
【国际标准分类号】:77_040_20
【页数】:4P.;A4
【正文语种】:


Product Code:SAE AIR4013
Title:Multiplex Data Bus Networks for Mil-Std-1760 Stores
Issuing Committee:As-1b Aircraft Store Integration Committee
Scope:This SAE Aerospace Information Report (AIR) will examine network aspects of open and shorted stubs, line reflections and bus loading due to network changes. Single network level is assumed, that is, no carriage store hierarchical levels. However, two passive network coupling variants called "branched bus" and "branched stub" will be introduced that possibly could be used in a stores management network.This report assumes familiarity with MIL STD 1553B.