Cov kev xav tau ntawm kev lag luam thickness gauges ntawm qhov chaw soj ntsuam ntawm lub workpiece
Nyob rau theem no ntawm lub thickness gauge nyob rau hauv lub nrhiav kom tau ntawm mechanical instruments feem ntau siv ultrasonic technology, ultrasonic kis tau tus mob nyob rau hauv cov khoom yog heev me me, nrhiav kom tau qhov tob yog loj, vim lub ultrasonic yoj nyob rau hauv lub heterogeneous interface yuav tshwm sim nyob rau hauv lub reflection, refraction. thiab lwm yam phenomena, tshwj xeeb tshaj yog, tsis tuaj yeem dhau los ntawm cov khoom siv roj av. Yog hais tias muaj qhov pores nyob rau hauv cov hlau, tawg, delamination thiab lwm yam tsis xws luag (tsis xws luag nyob rau hauv cov roj) los yog inclusions, ultrasonic propagation rau lub interface ntawm cov hlau thiab cov tsis xws luag, nws yuav yog tag nrho los yog ib feem ntawm qhov kev xav.
Cov kev cuam tshuam ultrasonic tsis tau txais los ntawm kev sojntsuam, ua tiav los ntawm cov khoom siv hluav taws xob sab hauv, thiab cov qauv sib txawv ntawm qhov siab thiab nrog qee qhov sib txawv tau tshwm sim ntawm lub vijtsam fluorescent ntawm lub ntsuas. Qhov saum npoo roughness ntawm lub workpiece yog loj heev, ua rau tsis zoo coupling ntawm lub sojntsuam thiab kev sib cuag nto, lub reflected echo yog tsawg, los yog txawm tsis tau txais lub ncha teeb liab. Rau saum npoo corrosion, coupling nyhuv yog cov khoom siv tsis zoo hauv kev pabcuam, cov kav dej, thiab lwm yam tuaj yeem ua rau sanded, grinded, thwarted thiab lwm yam kev kho saum npoo, txo qhov roughness, tab sis kuj oxides thiab xim txheej tuaj yeem raug tshem tawm, nthuav tawm cov hlau luster. , kom qhov kev sojntsuam thiab cov khoom raug tshuaj xyuas los ntawm tus neeg sawv cev sib txuas tuaj yeem ua tiav cov txiaj ntsig zoo sib txuas.
Lub vojvoog ntawm curvature ntawm lub workpiece yog me me heev, tshwj xeeb tshaj yog thaum lub me me txoj kab uas hla cov yeeb nkab thickness ntsuas, vim hais tias cov feem ntau siv sojntsuam nto rau lub dav hlau, thiab nkhaus nto tiv tauj rau qhov taw tes los yog kab sib cuag, lub suab siv ntawm tsawg transmittance ( kev sib txuas tsis zoo). Qhov tshwj xeeb sojntsuam rau me me yeeb nkab txoj kab uas hla (<6mm) can be used to measure the curved surface materials such as pipes more accurately. The detecting surface is not parallel to the bottom surface, the acoustic wave encounters the bottom surface to produce scattering, the probe can not accept the bottom wave signal.
Castings, austenitic steel vim lub koom haum tsis sib luag los yog ntxhib lis, ultrasound nyob rau hauv uas lub ultrasonic yoj los ntawm qhov loj tawg attenuation, lub ultrasonic yoj yog tawg mus rau hauv txoj kev nyuaj propagation, nws muaj peev xwm ua rau lub ncha annihilation, uas ua rau tsis pom. Ib qho kev sojntsuam tshwj xeeb (2.5MHz) rau cov pob zeb ntxhib uas muaj qhov qis dua tuaj yeem siv tau. Kev sojntsuam kev sib cuag nto muaj qee qhov hnav. Feem ntau siv cov thickness sojntsuam nto rau acrylic resin, kev siv mus sij hawm ntev yuav ua rau nws qhov chaw roughness, ua rau txo qis rhiab heev, ua rau cov zaub tsis raug.
500 # daim ntawv xuab zeb tuaj yeem siv rau xuab zeb, ua kom nws du thiab ua kom muaj kev sib luag. Yog tias nws tseem tsis ruaj khov, xav txog kev hloov qhov kev sojntsuam. Muaj ntau qhov corrosion nyob rau sab nraub qaum ntawm cov khoom ntsuas. Raws li lwm sab ntawm cov khoom nyob rau hauv kev ntsuam xyuas muaj xeb me ntsis, corrosion pits, ua rau acoustic attenuation, ua rau cov kev hloov pauv tsis tu ncua ntawm kev nyeem ntawv, thiab nyob rau hauv cov xwm txheej heev txawm tias tsis nyeem ntawv. (Cov khoom nyob rau hauv kev sim (xws li cov yeeb nkab) muaj deposits nyob rau hauv, thaum qhov sib txawv ntawm cov deposits thiab lub acoustic impedance ntawm lub workpiece tsis loj, lub thickness gauge qhia tus nqi ntawm phab ntsa thickness ntxiv rau cov thickness ntawm cov deposits.
