超声波探伤在车辆检修中的应用Applicationoful.pptx
郑州铁路职业技术学院超声波探伤在车辆检修中的应用Applicationofultrasonicflawdetectioninvehiclemaintenance车辆检测技术Vehicledetectiontechnology主讲人:时蕾FUNDAMENTALSOFSENSORTECHNOLOGYLecturer:ShiLei
超声波检测和探伤是目前应用十分广泛的无损探伤手段。Ultrasonicdetectionandflawdetectionarewidelyusednondestructivetestingmethods.特点:characteristic:基本原理:fundamental:既可检测材料表面的缺陷,又可检测内部几米深的缺陷,这是X光探伤所达不到的深度。Defectsonthesurfaceofthematerialcanbedetectedaswellasdefectsseveralmetersdeepinside,whichisadepththatcannotbereachedbyX-raydetection.用超声波发生器向工件内发射超声波,超声波遇到缺陷时受阻,检测缺陷反射回来的超声波和超声波通过工件后衰减的程度,即可发现缺陷及位置。Usetheultrasonicgeneratortoemitultrasonicwavestotheworkpiece,theultrasonicwavesareblockedwhentheyencounterdefects,detecttheultrasonicwavesreflectedbackbythedefectsandthedegreeofattenuationaftertheultrasonicwavespassthroughtheworkpiece,youcanfindthedefectsandpositions.超声波探伤在车辆检修中的应用
脉冲反射法:根据探伤波形进行判断的探伤,称为缺陷回波法(也称为二次回波法),该方法是脉冲反射法的基本方法。Pulsereflectionmethod:Accordingtothedetectionwaveformtojudgethedetection,calledthedefectechomethod(alsoknownasthesecondaryechomethod),themethodisthebasicmethodofpulsereflectionmethod.一、超声波探伤方法3.底面多次回波法Bottommultipleechomethod1.缺陷回波法Defectechomethod2.底面回波高度法Bottomechoheightmethod
一、超声波探伤方法穿透法:穿透法是依据脉冲或连续波穿透试件之后的能量变化来判断缺陷情况的一种方法。Penetrationmethod:Thepenetrationmethodisamethodtojudgethedefectsituationaccordingtotheenergychangeafterthepulseorcontinuouswavepenetratesthespecimen.
工作原理是:Howitworks:一、超声波探伤方法共振法:根据试件的共振特性来判断缺陷的方法,称为共振法。Resonancemethod:Accordingtotheresonancecharacteristicsofthespecimentojudgethedefectmethod,calledresonancemethod.声波在被探测试件内传播的过程中,当试件的厚度为超声波的半波长或半波长的整数倍时,由于入射波和反射波的相位相同,引起共振,因而仪器可显示出共振频率点,利用相邻的两个共振频率之差,通过以下公式可计算出试件厚度:Duringthepropagationofsoundwaveinthedetectedspecimen,whenthethicknessofthespecimenishalfwavelengthorintegermultipleofhalfwavelengthoftheultrasonicwave