Kukonza graphite kungakhale bizinesi yachinyengo, kotero kuyika zinthu zina patsogolo ndikofunikira kuti pakhale phindu komanso phindu.
Zowona zatsimikizira kuti graphite ndizovuta kupanga makina, makamaka ma electrode a EDM omwe amafunikira kulondola kwambiri komanso kusasinthika kwamapangidwe.Nazi mfundo zisanu zofunika kuzikumbukira mukamagwiritsa ntchito graphite:
Magiredi a graphite ndi ovuta kusiyanitsa, koma aliyense ali ndi mawonekedwe apadera komanso magwiridwe antchito.Maphunziro a graphite amagawidwa m'magulu asanu ndi limodzi malinga ndi kukula kwa tinthu tating'ono, koma magulu atatu ang'onoang'ono (tinthu tating'ono ta 10 microns kapena zochepa) amagwiritsidwa ntchito mu EDM yamakono.Udindo m'gululi ndi chizindikiro cha momwe mungagwiritsire ntchito komanso magwiridwe antchito.
Malinga ndi nkhani ya Doug Garda (Toyo Tanso, yemwe adalembera mlongo wathu wofalitsa "MoldMaking Technology" panthawiyo, koma tsopano ndi SGL Carbon), magiredi okhala ndi tinthu tating'onoting'ono tosiyanasiyana 8 mpaka 10 ma microns amagwiritsidwa ntchito roughing.Kumaliza kocheperako komanso mwatsatanetsatane ntchito zimagwiritsa ntchito magiredi a 5 mpaka 8 micron particle size.Ma elekitirodi opangidwa kuchokera ku magirediwa nthawi zambiri amagwiritsidwa ntchito popanga nkhungu ndi zitsulo zotayira, kapena popangira ufa wocheperako komanso zitsulo zokhala ndi sintered.
Mapangidwe atsatanetsatane komanso ang'onoang'ono, ovuta kwambiri ndi oyenera kukula kwa tinthu kuyambira 3 mpaka 5 microns.Ma elekitirodi amtundu uwu amaphatikizapo kudula mawaya ndi mlengalenga.
Maelekitirodi otsogola kwambiri ogwiritsira ntchito magiredi a graphite okhala ndi tinthu ting'onoting'ono toyambira 1 mpaka 3 amafunikira nthawi zambiri kuti agwiritse ntchito zitsulo zapadera zam'mlengalenga ndi carbide.
Polemba nkhani ya MMT, Jerry Mercer wa Poco Materials adazindikira kukula kwa tinthu, mphamvu yopindika, ndi kulimba kwa M'mphepete mwa nyanja monga zinthu zitatu zazikuluzikulu za magwiridwe antchito pakukonza ma electrode.Komabe, microstructure ya graphite nthawi zambiri imakhala yolepheretsa ntchito ya electrode pa ntchito yomaliza ya EDM.
M'nkhani ina ya MMT, Mercer adanena kuti mphamvu yopindika iyenera kukhala yoposa 13,000 psi kuonetsetsa kuti graphite ikhoza kusinthidwa kukhala nthiti zakuya ndi zoonda popanda kuthyoka.Njira yopangira ma electrode a graphite ndi yayitali ndipo ingafunike mwatsatanetsatane, zovuta kupanga makina, kotero kuonetsetsa kulimba ngati izi kumathandiza kuchepetsa ndalama.
Kulimba kwa m'mphepete mwa nyanja kumayesa kugwira ntchito kwa magiredi a graphite.Mercer akuchenjeza kuti magiredi a graphite omwe ali ofewa kwambiri amatha kutseka mipata ya chida, kuchepetsa makina opangira kapena kudzaza mabowo ndi fumbi, potero kuyika mphamvu pamakoma a dzenje.Zikatero, kuchepetsa chakudya ndi liwiro kungalepheretse zolakwika, koma kumawonjezera nthawi yokonza.Panthawi yokonza, graphite yolimba, yaying'ono-grained ingayambitsenso zinthu zomwe zili m'mphepete mwa dzenje.Zidazi zingakhalenso zowonongeka kwambiri ku chida, zomwe zimatsogolera kuvala, zomwe zimakhudza kukhulupirika kwa dzenje la dzenje ndikuwonjezera ndalama zogwirira ntchito.Nthawi zambiri, kuti mupewe kupatuka pazovuta zazikuluzikulu, ndikofunikira kuchepetsa kudya komanso kuthamanga kwa mfundo iliyonse ndi kulimba kwa M'mphepete mwa nyanja kuposa 80 ndi 1%.
Chifukwa cha momwe EDM imapanga chithunzithunzi cha galasi cha electrode mu gawo lokonzedwa, Mercer adanenanso kuti kudzaza kolimba, yunifolomu ya microstructure ndiyofunikira kwa ma electrode a graphite.Osafanana tinthu malire kumawonjezera porosity, potero kuwonjezeka tinthu kukokoloka ndi imathandizira elekitirodi kulephera.Panthawi yopangira makina opangira ma elekitirodi, mawonekedwe osafanana ang'onoang'ono amathanso kupangitsa kuti pakhale mawonekedwe osagwirizana - vutoli ndi lalikulu kwambiri pamakina othamanga kwambiri.Mawanga olimba mu graphite amathanso kupangitsa kuti chidacho chipatuke, zomwe zimapangitsa kuti ma elekitirodi omaliza asakhale osadziwika.Kupatuka uku kungakhale kocheperako kotero kuti dzenje la oblique likuwonekera molunjika polowera.
Pali makina apadera opangira ma graphite.Ngakhale kuti makinawa adzafulumizitsa kupanga makinawo, si makina okhawo amene opanga angagwiritse ntchito.Kuphatikiza pa kuwongolera fumbi (zofotokozedwa pambuyo pake m'nkhaniyi), zolemba zam'mbuyomu za MMS zidanenanso za phindu la makina okhala ndi ma spindles othamanga komanso kuwongolera ndi liwiro lalikulu lopangira ma graphite.Moyenera, kuwongolera mwachangu kuyeneranso kukhala ndi mawonekedwe amtsogolo, ndipo ogwiritsa ntchito azigwiritsa ntchito pulogalamu yokhathamiritsa njira.
Poika ma elekitirodi a graphite, kutanthauza kuti, kudzaza ma pores a graphite microstructure ndi tinthu tating'onoting'ono tating'onoting'ono, Garda amalimbikitsa kugwiritsa ntchito mkuwa chifukwa amatha kupanga mokhazikika ma aloyi apadera amkuwa ndi faifi tambala, monga omwe amagwiritsidwa ntchito popanga zinthu zakuthambo.Magiredi a graphite opangidwa ndi Copper amatulutsa zomaliza zabwino kwambiri kuposa magiredi osalowetsedwa amtundu womwewo.Angathenso kukwaniritsa kukhazikika kokhazikika pamene akugwira ntchito pansi pa zovuta monga kusasunthika bwino kapena osadziwika bwino.
Malinga ndi nkhani yachitatu ya Mercer, ngakhale ma graphite opangidwa - mtundu womwe umagwiritsidwa ntchito popanga ma elekitirodi a EDM-ndiwopanga biologically inert ndipo motero poyamba savulaza anthu kuposa zida zina, mpweya wolakwika ungayambitsebe mavuto.Synthetic graphite ndi conductive, yomwe ingayambitse mavuto ku chipangizocho, chomwe chingakhale chachifupi chikakumana ndi zida zakunja.Kuphatikiza apo, ma graphite opangidwa ndi zinthu monga mkuwa ndi tungsten amafunikira chisamaliro chowonjezereka.
Mercer anafotokoza kuti diso la munthu silingathe kuona fumbi la graphite m'magulu ang'onoang'ono, koma lingayambitsebe kupsa mtima, kung'ambika ndi kufiira.Kukhudzana ndi fumbi kumatha kukhala kowawa komanso kukwiyitsa pang'ono, koma sikutheka kuti kulowetsedwa.Chiwerengero cha nthawi (TWA) chiwongolero chowonetsera fumbi la graphite m'maola a 8 ndi 10 mg / m3, yomwe imakhala yowoneka bwino ndipo sichidzawoneka mu dongosolo losonkhanitsa fumbi lomwe likugwiritsidwa ntchito.
Kuchulukirachulukira kwa fumbi la graphite kwa nthawi yayitali kungayambitse tinthu tating'onoting'ono ta graphite kukhala m'mapapo ndi bronchi.Izi zingayambitse matenda aakulu a pneumoconiosis otchedwa graphite matenda.Graphitization nthawi zambiri imagwirizana ndi graphite yachilengedwe, koma nthawi zina imakhala yogwirizana ndi graphite yopanga.
Fumbi limene limaunjikana kuntchito limatha kuyaka kwambiri, ndipo (m’nkhani yachinayi) Mercer akunena kuti likhoza kuphulika pansi pa zinthu zina.Pamene kuyatsa kumakumana ndi ndende yokwanira ya tinthu tating'ono tomwe timayimitsidwa mumlengalenga, moto wafumbi ndi kuwonongeka kumachitika.Ngati fumbi limamwazikana mochuluka kapena lili pamalo otsekedwa, nthawi zambiri limatha kuphulika.Kuwongolera mtundu uliwonse wa chinthu chowopsa (mafuta, okosijeni, kuyatsa, kufalikira kapena kuletsa) kumatha kuchepetsa kuthekera kwa kuphulika kwa fumbi.Nthawi zambiri, mafakitale amayang'ana kwambiri mafuta pochotsa fumbi kuchokera kugwero kudzera mu mpweya wabwino, koma masitolo ayenera kuganizira zonse kuti apeze chitetezo chokwanira.Zida zowongolera fumbi ziyeneranso kukhala ndi mabowo osaphulika kapena makina oletsa kuphulika, kapena kuyikidwa pamalo opanda mpweya.
Mercer wapeza njira ziwiri zazikulu zoyendetsera fumbi la graphite: makina othamanga kwambiri a mpweya ndi osonkhanitsa fumbi-omwe amatha kukhazikika kapena kunyamulidwa malinga ndi ntchito-ndi machitidwe amadzi omwe amadzaza malo ozungulira wodula ndi madzimadzi.
Masitolo omwe amapanga pang'ono pokonza ma graphite amatha kugwiritsa ntchito chipangizo chonyamulika chokhala ndi fyuluta yapamwamba kwambiri ya particulate air (HEPA) yomwe ingasunthidwe pakati pa makina.Komabe, ma workshop omwe amakonza ma graphite ambiri nthawi zambiri amayenera kugwiritsa ntchito dongosolo lokhazikika.Kuthamanga kwa mpweya wocheperako kuti mugwire fumbi ndi mapazi 500 pa mphindi, ndipo liwiro la njirayo limakwera mpaka mamita 2000 pa sekondi imodzi.
Makina onyowa amatha kukhala pachiwopsezo cha "wicking" wamadzimadzi (kutengeka) muzinthu za elekitirodi kuti achotse fumbi.Kulephera kuchotsa madzimadzi musanayike electrode mu EDM kungayambitse kuipitsidwa kwa mafuta a dielectric.Ogwira ntchito ayenera kugwiritsa ntchito njira zopangira madzi chifukwa njirazi sizimakonda kuyamwa mafuta kusiyana ndi zopangira mafuta.Kuyanika ma elekitirodi musanagwiritse ntchito EDM nthawi zambiri kumaphatikizapo kuyika zinthuzo mu uvuni wa convection kwa pafupifupi ola limodzi pa kutentha pang'ono pamwamba pa nsonga ya evaporation ya yankho.Kutentha sikuyenera kupitirira madigiri 400, chifukwa izi zidzasokoneza ndi kuwononga zinthuzo.Oyendetsa sayeneranso kugwiritsa ntchito mpweya woponderezedwa kuti awumitse electrode, chifukwa kuthamanga kwa mpweya kumangokakamiza madziwo kulowa mkati mwa electrode.
Princeton Tool ikuyembekeza kukulitsa mbiri yake yazinthu, kukulitsa mphamvu zake ku West Coast, ndikukhala ogulitsa amphamvu onse.Kuti mukwaniritse zolinga zitatuzi panthawi imodzi, kupeza malo ogulitsira makina ena kunakhala chisankho chabwino kwambiri.
Chipangizo cha EDM cha waya chimazungulira waya wa electrode wowongoka mozungulira muzitsulo za E zoyendetsedwa ndi CNC, kupereka msonkhanowu ndi chilolezo cha workpiece ndi kusinthasintha kuti apange zida zovuta komanso zolondola kwambiri za PCD.
Nthawi yotumiza: Sep-26-2021