Document OeDx88aekBM7rx3XnedY9G1X

mm I t.eTlfc * , 4 i i i : J .1 tmm. ***< .cfmsmm** LIA2A801 *di lAimifr r LEAD INDUSTRIES ASSOCIATION, INC. It! MADISON AVENUE NCW vomc 17, N. Y. March JO, X9& SUBJECT: LEAD EIKCOWATE TITAKATg To Meriber* of the Lead Industries Association, Zacs Attached la a reprint free the February 19& Issue of "Cerealc Age* of aa article describing the use of lead rlrcooate tlteneta In ultraeonlc cleaning device*. This article vaa baaed on the paper presented at the l&it annual aeetlng of L.I.A. We bellere that It 1* a useful, handy and condensed treat ment of this subject vhlch ve vill use for distribution at our trade show exhibits, such aa the Design Engineering `Ibcv, and In ansverlng inquiries an this subject. Very truly yours. RLZ:ak Enc. Executive Vice President - 5 o r----------' Look AJt *4 T wsrr-jp pan LIA24802 // . f PZT Transducers Help Broaden Market for Ultrasonic Cleaning Sy: H. F. 0*f*rm*n Vk Pre*kfnt. Marketing Bronkon Instruments, Inc u, fts*ostc ckaniny a complex phenomena which in lhe urtplc*l *en\c can he conwdefed at an cvcelkm k rubbing action. The speed and cf fioenc) of an ultratonic cleaning operation depenJ upon the amount of castUtional energy or activity. the phyvcal and chemical prop erty of the ckamny solution and 'he nature of the *otl at well at the pa.1 being cleaned. Sound m in a liquid can he considered at ahetnaic compressions and rarrlaclKTit Cavities are formed when the %ound energy tod it suIfKient to stress the liquiJ be yond tt tenwk urcnglh during the rarefaction phase At the pressure *>np pNiac, the cavity collapse themselves creating high. instantancsHis pressures SKck emanate from the point id implosion The rale at which thoc easily burn and imptdc n proportional to the some frequency, which normally is between 2*V*tO and W.tico pvln per vciwil The expand*w and adfapsc of a caul) in a liquid * known casrtatMHt and carnet a strong mechanical scrub bing actant ah.h **ccurs at art) surface in the casitatiny liquid factors controlling casitation in a liquid include surface lcns**n. taper procure. density ..nd sn^osit' tn a yi\cn Ik iu h I ihcve fact*** tend to *ptum/e in a particular temperature ranye to produce the greatest cavitational i-ncfp and (hut the nvnt intensive KfuWHnf action This scrubbing action, for alt practical purpsHcx, can he con sidered mechanical criHum In actual use the scrubbing rffcvt of cavitation rs usualI) combined with the actam of aqueous or solvent ckaniny sotutavns so that the advantage o( Kdh ckaniny processes arc obtained In additaHt to mechamcal scrubbing. cavttatwvi also Irrvh to speed-up cleaning h solvent actant bs rrduemy chemical concentration gradients, removing re action products and maintaining a fresh supply l wdutMHi at the cleamny interface. An ultrasonic fcncfatot is used to onvert line current into radio frequency current at the desired frequency, which subsequently ts convened h> a transducer into sound ot mechanical energy at the same frequency Adapted from a |apcr presented before the '2nd inrmJ meeting of the I Cad Industries Association held in Chi cago. May J, 1961. Transducers fall into two main classes: piezoelectric and maynetivstnctise In the first instance a material which changes dimension in the pretence rf an electrical field is uiih/ed. In the second the material rs influenced by a magnet* field. Due to the Urge difference in conversion efficiencies, 70*1 to VO4! for cfcctrostrictive compared with 2o*T u> 40*1 for magneUHUxttve, we uulue Jram- duccfs of the elcctrostrvctise type. Initial!)- hafium tiunate was used as the acuv* ma terial. hut it had two mayor drawbacks its inability to operate continuous!) ahose 160 F and poor maintenance Characteristics from the standpoint of transducer rebuilding costs. The use of PZT (lead nrcacute tiunate) has eliminated these pfidslems. Ahhouyh more espensise than hanura titanaie. H is capable of handling much greater power in puts A unique sanjwieh l>pe design, which clamps a rcU- tiseU smalt anvHint of P/T between metal plain, has yielded a transduce/ element with )l I WcttKal u mechanical cssnufsion efficiency of **i' ctHpp-frx! with 7o'. tor Barium liunate 2 <>fKiatiny temperatufts m cvcs*ss >f 2W0 F f in^inienata'c eWs lr.*nvlu<ir r*cr-erts in their mjnut.*.-turcd can- rw< he u m.iI ii fr. iis m a It i\ f.e this that thes rf/i n.*fni.ill>. prlt.vted h> a stainless steel or other chenK j| icMstart *tt.*s Multiple ek*m*fiis arc attached to a si jinli-ss we, I K h\ a spcsial h*nJir.y technique, whr^h i* n>bin,v h./h nKNh-mcal strength with psyj acxwzv Ik * ctfi.K>Rk 11r * wtHHi i-l the b,nwnp which rs in o h i- U\1 wh the liquid <vo ih h : w.*e and the elements on the fXiv.1 i- talkJ tl< lasJiatlfiy MirtakC Sitae ultraM'nu- vlc->nmy i\ mcv'hanK'al it easy to realize that a radutiny surla.c wl! cttsJe As it riHJghi ns H kiss's it ahtlils to cfticicnth radiate enerys. I ong term evpericTKC inJuates an cffrctisc transducer life sd h,i*m ii 9.iin h*u/s after which it is necessary to re build them Transducers utih/my PZT can he rebuilt at >)'# of their initial cost a% compared with H0'i rehuikliny ctWs f^ oklcf fspc lfanv!u,s*r> Ihis fact well justifWs the uc of P/I, smee it has made piisvhk large mstallatawss whwh w s h j IJ not he cciHvsous'atly feasible using inJinary tram- ducerv due to high rebuilding cods. I'liwu a capit.il investment xtandptanl. the higher oper ating ctlis Kixy td p/| transducer ekments has made |w h - ubk a fssliKtKMi in si>st smee a larger anwHint id the in- Ci>ming Invs* pimer is converted to useful mechanKal cncrgv Ihcsc rcslustnins will broaden the use id ultra- w h ik * s kaiung whn h is CiHiipeftlivc with m*fe CinventK*nj! fiHms of cleaning / N7> Xwpektfad from CCSAMfC AGF fCftRUAftY 1942 Ouinbufed by lead fndu(ret Attockrlion, Inc. 292 Moduon Avenue New York 17, N Y. N 1753.01