Optimization Frequency Design of Eddy Current Testing

Transcription

1 5th WSEAS Int. Cnfeence n Appled Electagnetcs, Weless and Optcal Cuncatns, Tenefe, Span, Decebe 14-16, Optzatn Fequency Desgn f Eddy Cuent Testng NAONG MUNGKUNG 1, KOMKIT CHOMSUWAN 1, NAONG PIMPU 2 AND TOSHIFUMI YUJI 3 1 Depatent f Electcal Technlgy Educatn Kng Mngkut s Unesty f Technlgy Thnbu,Bangkk 2 Suanaee Unesty f Technlgy, Naknatchasa THAILAND 3 Ota Natnal Cllege f Technlgy, Ota JAPAN Eal:nang_kutt@yah.c Abstact: The pupses f ths eseach wee t cnstuct the nndestucte etal testng ntuent by usng eddy cuent ethd and t fnd an ptal fequency f the etal testng ntuent. The testng ntuent cnsst f a sne wae scllat ccut whch can adjust the fequency between khz, and a 50 hs sens ccut. Thee ae thee knds f testng ntuent. The fst was the nndestucte pefectn testng by usng eddy cuent ethd. The saple ns ae cnstucted wth dffeent pefectn n suface. The utput sgnals f testng f the sens ccut ae cpaed. The secnd was the nndestucte categzatn etal testng by usng eddy cuent ethd. Many knds f etals ae taken t testng. The last ne was the nndestucte testng f fndng the thckness f fls n n by usng eddy cuent ethd. In ths testng the thckness f fls aed between cns. In all testng, dffeences f the sgnal testng wee cpaed t analyze the ptal fequency f the testng ntuent. The esults f eseach shwed that the nndestucte etal testng ntuent by usng eddy cuent ethd can be used t fnd a dffeent pefecte n, categze the etal and fnd thckness f fls. In addtn, the ange f an ptal fequency s 30 khz t 70 khz f testng ntuent. Keywds Nndestucte, eddy cuent, thckness f fls, ptal fequency 1. Intductn Nwadays Thaland has s any ndustal deelpents; theefe, thee ae a lt f nests, bth lcal and ntenatnal. In de t be able t cpete wth the cuntes, Thaland needs t cntl ts pductn standads and elablty [1]. Standads ae the key fact f Thaland ndusty. That s t say, t deelp ndusty eans t deelp technlgy f the st pat. At the ent, thee s technlgy called nndestucte etal testng whch s wdely used n the ndusty. Ths technlgy s used f 3 pupses, whch ae t ensue assue the qualty cntl, t test the qualty accdng t the standads, and t keep antenance. The wdely used nndestucte etal testng ethd n the ndusty s Eddy Cuent Methd Testng ET, f exaple, t test etal qualty suface f etal. Eddy cuent culd be ade by hgh fequency agnetc feld. The agnetc feld happens when hgh fequency AC cuent entes pay cl. In case thee s cntnuus space nsde the wk ateal, the eddy cuent wll be hghe. In case thee s n cntnuus space nsde the wk ateal, the eddy cuent wll be lwe. Ths dffeence culd be used t easue the cntnuty f the wk ateal by usng eddy cuent [2-4]. Ths eseach was t desgn and deelp nndestucte etal testng ntuent by usng eddy cuent ethd, whch cnssted f scllat ccut whch can adjust fequency and a 50 hs sens ccut, and t exane the pact f used fequency n testng as well. 2. Analyss and Desgn Desgn f etal testng ntuent was t be used n fndng pefectn f n, categze any knds f etal, and t fnd the thckness f fls n n suface by nndestucte testng. The eseaches appled the pncples f eddy cuent t desgn sne wae scllat whch culd adjust fequency between khz, wth a 50 hs sens ccut. Detals elated t the analyss and the desgn culd be shwn n fs f blcks cntllng each pat f f nndestucte etal testng ntuent by eddy cuent ethd as fllws:

2 5th WSEAS Int. Cnfeence n Appled Electagnetcs, Weless and Optcal Cuncatns, Tenefe, Span, Decebe 14-16, Sens Apl fe Oscls cpe Pwe Apl fe Mete 470Ω Oscllat 1kΩ Fgue 1. Cpnents f the Nndestucte Metal Testng Syste by Eddy Cuent Methd 5kΩ 5kΩ 2.1 Desgn f Wae Oscllat Ccut[5] Sne wae scllat ccut culd be sply ade by ne IC n de t educe the cplexty f desgn and ateal. IC nube X2206 whch culd be fund at a easnable pce and easy t desgn was used. The ccut stuctue was as shwn n Fgue 2 and the fequency s 1 f = C 2.2 Desgn f Ccut f Electcal Vltage Aplfcatn Sgnal f scllat ccut ust be aplfed s that t culd be used n a pactcal way. Theefe, ccut f electcal ltage aplfcatn ust be desgned by usng p-ap nube CA3130. Ths ccut wuld wk faste and culd be used wth dffeent ange f fequency. Pncple n desgn and pactce was based n netng type sgnal aplfe ccut. Gan ate depends n and f and culd be calculated by aplfe ate A CL f ccut n Fgue 2 as shwn n the fllwng equatn: f ACL = (2) Theefe, utput culd be calculated by the equatn: f VO = xe (3) 2.3 Desgn f Ccut f Electcal Pwe Aplfe Sgnal f scllat ccut had t be aplfed by netng type aplfe ccut. The utput sgnal was hghe but that sgnal culd nt de 50 hs; theefe, ths sgnal had t be aplfed by tansst aplfe ccut. Tansst nube H1061 was electcal pwe aplfe s that t culd dstbute ltage t 50 hs sens ccut (1) Fgue 2 Wae Oscllat Ccut A β' L = = (4) n π A = V Z n = A (5) n L G= A A (6) = A V = V (7) 2.4 Desgn f Sens Ccut Inducte cl was an electcal lad. Electcal cuent whch uns thugh cl wuld nduct because agnetc lnes f fce tk place nsde nducte cl. Vltage dp f nducte cl f ccut culd be calculated by the fllwng equatn: V L n dl = L = L( ωi csωt) = ωli csωt (8) dt When sens ccut was used t test pefectn f etal by usng nndestucte eddy cuent ethd and sens ccut gt clse t etal. The nductance alue f the cl wuld change. Ths change was due t aus easns lke etal type, sze f pefectn, dstance and scllat fequency. Thus, nductance alue f sens changed dffeently. 3. Expeent Ths expeent was t cnstuct 3 knds f nndestucte etal testng by eddy cuent ethd as fllws[6-8]: 1. The fst was t d a nndestucte test f etal pefectn by usng eddy cuent ethd. The test was a sulatn by akng dffeent pefectn sze n etal and then sens ccut was used t test s

3 5th WSEAS Int. Cnfeence n Appled Electagnetcs, Weless and Optcal Cuncatns, Tenefe, Span, Decebe 14-16, by adjustng fequency between khz dung the expeent. Fgue 3 A Nndestucte Test f Metal Ipefectn by Usng Eddy Cuent Methd 2. The secnd was t d a nndestucte categzatn f etal by usng eddy cuent ethd. The test was a sulatn by takng any knds f etal (n, cppe, bass, alunu and stanless steel) t the test n de t categze etal. The test was dne by sens ccut wth a 50 hs ccut and the fequency used was aund 45 khz dung the test. Fgue 5. A Nndestucte Test t Fnd the Thckness f Fls n In by Usng Eddy Cuent Methd 4. esults 4.1 esults f Nndestucte Test f Metal Ipefectn Nndestucte test f etal pefectn by usng eddy cuent ethd was the test t fnd ut the dffeences f pefectn n n. Saple n had been dlled wth dffeent wdth and depth n suface. The fequency used was between khz and then the utput sgnals wee pltted n a gaph t cpae the dffeences f pefectn hle length 2 hle length 3 hle length 5.95 Fgue 4. A Nndestucte Test f Metal Categzatn by Usng Eddy Cuent Methd 3. The thd was t d a nndestucte test f fndng the thckness f fls n n by usng eddy cuent ethd. The thckness f fls n the test aed between cns. The test wuld ncease 100 cns f fl thckness n each te and the fequency used was between khz n de t fnd ut the ptal fequency. It was fund that the fequency between khz shwed the st bus esults f sgnal change. Ths fequency was then was the ptal fequency. Vltage () Hle daete () Fgue 6. In pefectn at 40 khz 4.2 esults f Nndestucte Test f Metal Categzatn Nndestucte test f etal categzatn by usng eddy cuent ethd was the test t fnd ut the

4 5th WSEAS Int. Cnfeence n Appled Electagnetcs, Weless and Optcal Cuncatns, Tenefe, Span, Decebe 14-16, dffeences n knd f etal (n, cppe, bass, alunu and stanless steel). The fequency used was aund 45 khz. The utput sgnals wee pltted n a gaph as shwn n Fgue esults f Test f Fl Thckness n Ins Nndestucte test f fl thckness n n by usng eddy cuent ethd was the test t fnd ut dffeences n fl thckness. Fls wth 7 dffeent knds f thckness wee used f the test wth dffeent fequency. The utput sgnals wee pltted n gaph t shw the elatnshp twads t fl thckness as Fgue 8-9. Fgue 7 Gaph f Electcal Attbute f Metal Fgue 8 Typcal Test at 40 khz Magnet01 Magnet0 Usua l Stalet Bas s Alunu Cppe Fgue 9 Typcal Test at 60 khz 5. Cnclusns Ths eseach was t ppse hw t desgn and cnstuct nndestucte etal testng ntuent by usng eddy cuent ethds. Thee wee 3 knds as fllws: 1. Nndestucte test f etal pefectn by usng eddy cuent ethd was a sulatn test by akng dffeent pefectn sze and then 50 hs sens ccut was used t test. It was fund that the fequency between khz shwed the st bus dffeences and t was sutable f ths knd f test. 2. Nndestucte test f etal categzatn by usng eddy cuent ethd was a sulatn test by takng any knds f etal t the test and then 50 hs sens ccut was used t test. It was fund that n shwed the bus dffeences and t was sutable f ths knd f test. 3. Nndestucte test f fl thckness n n by usng eddy cuent ethd was dne by testng fls wth thckness f cns. The test wuld ncease 100 cns f fl thckness n each te and the fequency used was between khz n de t fnd ut the ptal fequency. It was fund that the fequency between khz shwed the st bus dffeences and t was sutable f ths knd f test. F ths study, t culd be cncluded that the testng nstuent f eddy cuent ethd culd be used t d nndestucte etal tests elated wk n any ndusty. Due t the patent easn, the nfatn f ths nstuent des nt shw n e detal. efeences [1]. Fuj Sat, Pathat Panthubanyng, Pundtj Aayannt, Kkat Bunchukusl, Syt Ssatht, 1987, Nndestucte Test, 2 nd

5 5th WSEAS Int. Cnfeence n Appled Electagnetcs, Weless and Optcal Cuncatns, Tenefe, Span, Decebe 14-16, Ipessn, Technlgy Ptn Asscatn (Thaland-Japan), Bangkk, pp [2] T. Takag, M. Hasht, H. Fukut, M. Kukawa, and K. Mya et al., Benchak del f eddy cuent testng f stea geneat tube: expeent and nuecal analyss, Intenatnal Junal f Appled Electagnetcs n Mateals, l. 5, n. 2, pp , [3] H. Fukut, H. Huang, T. Takag, and J. Tan, Identfcatn f cack depths f eddy cuent testng sgnal, IEEE Tansactns n Magnetcs, l. 34, n. 5, pp , Sept [4] A. Kaea, Slutn f asyetc cnduct wth a whle by FEM usng edge-eleent, COMPEL, l. 9, pp , [5] Wte Asaaangsee, Chatchawal Tetwng, Knchulee Chasatht, 1988, Usage f Op-Ap and Lnea IC, 1 st Ipessn, Se-Educatn, Bangkk, pp [6] V.S.Cecc, G.Van Dunen,and F.L.Shap, 1986, Adanced Manual F: Eddy Cuent Test Methd, Canadan Geneal Standads Bad, Canada, pp 5-24 [7] Tshyuk Takag, 1998,Nuecal Ealuatn f Celatn between Cack Sze and Eddy Cuent Testng Sgnal by a Vey Fast Sulat,IEEE Tansactns n Magnetcs, Vl. 34, N. 5, Septebe 1998, pp [8] Xa-Me Pe, 2002, A Fequency Spectu A n a l y s s M e t h d f E d d y C u e n t Nndestucte Testng, Pceedngs f the Fst Intenatnal Cnfeence n Machne Leanng and Cybenetcs, Bejng, 4-5 Nebe 2002, pp