Makhalidwe a 1.EDM a zipangizo za graphite.
1.1.Kutulutsa liwiro la makina.
Graphite ndi zinthu zopanda zitsulo zomwe zimasungunuka kwambiri 3, 650 ° C, pamene mkuwa uli ndi malo osungunuka a 1, 083 ° C, kotero kuti electrode ya graphite imatha kupirira mikhalidwe yambiri yamakono.
Pamene kumaliseche m'dera ndi sikelo ya elekitirodi kukula ndi zazikulu, ubwino mkulu dzuwa akhakula Machining wa zinthu graphite zoonekeratu.
Kutentha kwa graphite ndi 1/3 yamkuwa, ndipo kutentha komwe kumapangidwa panthawi yotulutsa kungagwiritsidwe ntchito kuchotsa zipangizo zachitsulo bwino.Choncho, processing dzuwa la graphite ndi apamwamba kuposa elekitirodi mkuwa sing'anga ndi processing bwino.
Malinga ndi zomwe zidachitika pokonza, kuthamanga kwa ma electrode a graphite ndi 1.5 ~ 2 nthawi mwachangu kuposa ma elekitirodi amkuwa pansi pamikhalidwe yoyenera.
1.2.Kugwiritsa ntchito ma elekitirodi.
Graphite elekitirodi ali ndi khalidwe kuti akhoza kupirira zinthu mkulu panopa, kuwonjezera, pansi pa chikhalidwe yoyenera roughing kolowera, kuphatikizapo mpweya zitsulo workpieces opangidwa pa Machining kuchotsa zili ndi madzimadzi ntchito pa kutentha kutentha kuwonongeka kwa particles mpweya, zotsatira polarity, pansi mchitidwe wa tsankho kuchotsa zili, mpweya particles kutsatira elekitirodi pamwamba kupanga wosanjikiza zoteteza, kuonetsetsa graphite elekitirodi mu imfa yaing'ono mu Machining akhakula, kapena ngakhale "ziro zinyalala".
Kutayika kwakukulu kwa electrode mu EDM kumachokera ku makina ovuta.Ngakhale kuti chiwongoladzanja ndichokwera kwambiri pokonzekera kumaliza, kutayika konseko kumakhala kochepa chifukwa cha malipiro ang'onoang'ono a makina omwe amasungidwa magawo.
Nthawi zambiri, kutayika kwa elekitirodi ya graphite ndikocheperako poyerekeza ndi ma elekitirodi amkuwa pamakina ovuta kwambiri apano komanso pang'ono kuposa ma elekitirodi amkuwa pakumaliza kukonza.Kutayika kwa electrode kwa graphite electrode ndikofanana.
1.3.Ubwino wa pamwamba.
The tinthu awiri a graphite zakuthupi zimakhudza mwachindunji roughness pamwamba EDM.Zing'onozing'ono ndi momwe zimakhalira, kutsika kwapamwamba kungathe kupezeka.
Zaka zingapo zapitazo pogwiritsa ntchito tinthu tating'ono ta phi 5 microns m'mimba mwake graphite zakuthupi, malo abwino kwambiri amatha kukwaniritsa VDI18 edm (Ra0.8 microns), masiku ano m'mimba mwake ma graphite atha kukwaniritsa mkati mwa 3 microns wa phi, malo abwino kwambiri. akhoza kukwaniritsa khola VDI12 edm (Ra0.4 mu m) kapena mlingo wapamwamba kwambiri, koma graphite elekitirodi kuti galasi edm.
Zida zamkuwa zimakhala ndi zochepetsera zochepetsera komanso zosakanikirana, ndipo zimatha kukonzedwa mokhazikika pansi pazovuta.Pamwamba pa roughness akhoza kukhala zosakwana Ra0.1 m, ndipo akhoza kukonzedwa ndi galasi.
Chifukwa chake, ngati makina otulutsa amatsata bwino kwambiri pamwamba, ndibwino kugwiritsa ntchito zinthu zamkuwa ngati ma elekitirodi, omwe ndi mwayi waukulu wa elekitirodi yamkuwa pamagetsi a graphite.
Koma mkuwa elekitirodi pansi pa chikhalidwe lalikulu panopa lokhazikika, elekitirodi pamwamba n'zosavuta kukhala akhakula, kuoneka ngakhale mng'alu, ndi graphite zipangizo sakanakhala ndi vutoli, pamwamba roughness chofunika VDI26 (Ra2.0 microns) za processing nkhungu, ntchito graphite elekitirodi akhoza kuchitidwa kuchokera coarse kuti bwino processing, amazindikira yunifolomu pamwamba tingati, zofooka pamwamba.
Kuonjezera apo, chifukwa cha mapangidwe osiyanasiyana a graphite ndi mkuwa, malo otsekemera amadzimadzi a graphite electrode amakhala okhazikika kuposa a electrode yamkuwa.Choncho, pamene pamwamba roughness wa VDI20 kapena pamwamba ndi kukonzedwa, pamwamba granularity wa workpiece kukonzedwa ndi elekitirodi graphite ndi wosiyana kwambiri, ndipo zotsatira za njere pamwamba kuposa kutulutsa pamwamba pa elekitirodi mkuwa.
1.4.Kulondola kwa makina.
The coefficient of matenthedwe kukula kwa graphite zakuthupi ndi yaing'ono, ndi coefficient of matenthedwe kukula kwa zinthu zamkuwa ndi 4 nthawi graphite zakuthupi, kotero mu kumaliseche processing, graphite elekitirodi ndi zochepa sachedwa mapindikidwe kuposa electrode mkuwa, amene angapeze khola ndi odalirika processing kulondola.
Makamaka pamene nthiti yakuya ndi yopapatiza ikukonzedwa, kutentha kwapafupi kumapangitsa ma elekitirodi amkuwa kupindika mosavuta, koma electrode ya graphite satero.
Kwa electrode yamkuwa yokhala ndi chiŵerengero chakuya-m'mimba mwake, mtengo wina wowonjezera kutentha uyenera kulipidwa kuti uwongolere kukula kwake panthawi yokonza makina, pamene electrode ya graphite sikufunika.
1.5.Kulemera kwa elekitirodi.
Zinthu za graphite ndizochepa kwambiri kuposa zamkuwa, ndipo kulemera kwa electrode ya graphite ya voliyumu yomweyi ndi 1/5 yokha ya electrode yamkuwa.
Zitha kuwoneka kuti kugwiritsa ntchito graphite ndikoyenera kwambiri kwa electrode ndi voliyumu yayikulu, yomwe imachepetsa kwambiri katundu wa spindle wa chida cha makina a EDM.The elekitirodi sadzachita kusokoneza clamping chifukwa kulemera kwake lalikulu, ndipo adzatulutsa kusamuka kusamutsidwa mu processing, etc. Tingaone kuti n'zofunika kwambiri ntchito graphite elekitirodi mu yaikulu nkhungu processing.
1.6.Kuvuta kwa Electrode.
Kuchita kwa makina a graphite ndikwabwino.Kukana kudula ndi 1/4 yokha ya mkuwa.Pansi pamikhalidwe yoyenera, mphamvu ya mphero ya graphite elekitirodi ndi nthawi 2-3 kuposa electrode yamkuwa.
Elekitirodi ya graphite ndiyosavuta kuyimitsa Angle, ndipo itha kugwiritsidwa ntchito pokonza chogwirira ntchito chomwe chiyenera kumalizidwa ndi maelekitirodi angapo kukhala electrode imodzi.
Wapadera tinthu dongosolo la zinthu graphite amalepheretsa burrs kuchitika pambuyo electrode mphero ndi kupanga, amene akhoza mwachindunji kukwaniritsa zofunika ntchito pamene burrs sali kuchotsedwa mosavuta ma modelling ovuta, motero kuthetsa ndondomeko kupukuta pamanja la elekitirodi ndi kupewa mawonekedwe. kusintha ndi kukula zolakwika chifukwa cha kupukuta.
Tikumbukenso kuti, chifukwa graphite ndi fumbi kudzikundikira, mphero graphite kutulutsa fumbi kwambiri, kotero makina mphero ayenera kukhala ndi chisindikizo ndi fumbi kusonkhanitsa chipangizo.
Ngati kuli kofunikira kugwiritsa ntchito edM pokonza ma elekitirodi a graphite, ntchito yake yokonza si yabwino ngati zinthu zamkuwa, kuthamanga kwachangu kuli pafupi 40% pang'onopang'ono kuposa mkuwa.
1.7.Kuyika ndi kugwiritsa ntchito Electrode.
Zinthu za graphite zili ndi katundu wabwino wolumikizana.Itha kugwiritsidwa ntchito kumangiriza graphite ndi fixture ndi mphero ya elekitirodi ndi kutulutsa, zomwe zimatha kupulumutsa njira yopangira dzenje lopangira ma elekitirodi ndikusunga nthawi yogwira ntchito.
Zinthu za graphite zimakhala zowonongeka, makamaka electrode yaying'ono, yopapatiza komanso yayitali, yomwe imakhala yosavuta kusweka pamene ikugwiritsidwa ntchito ndi mphamvu yakunja, koma imatha kudziwa nthawi yomweyo kuti electrode yawonongeka.
Ngati ndi electrode yamkuwa, imangopindika osati kusweka, yomwe ndi yoopsa kwambiri komanso yovuta kuipeza pogwiritsira ntchito, ndipo idzatsogolera mosavuta ku zidutswa za workpiece.
1.8.Mtengo.
Zinthu zamkuwa ndizinthu zosasinthika, mtengo wamtengo wapatali udzakhala wokwera mtengo, pamene mtengo wa graphite umakhala wokhazikika.
Mkuwa chuma mtengo kukwera m'zaka zaposachedwapa, opanga zazikulu za graphite kuwongolera ndondomeko kupanga graphite kupanga mwayi mpikisano, tsopano, pansi pa buku lomwelo, ambiri a graphite elekitirodi mtengo zinthu ndi mtengo wa zipangizo mkuwa elekitirodi ndithu, koma ndi graphite akhoza kukwaniritsa processing imayenera, kuposa ntchito elekitirodi mkuwa kupulumutsa maola ambiri ogwira ntchito, ofanana kuchepetsa mtengo kupanga mwachindunji.
Mwachidule, pakati pa 8 edM makhalidwe a graphite elekitirodi, ubwino wake n'zoonekeratu: dzuwa la mphero elekitirodi ndi kumaliseche processing ndi bwino kwambiri kuposa electrode mkuwa;Elekitirodi yayikulu imakhala yolemera pang'ono, kukhazikika kowoneka bwino, ma elekitirodi owonda siwosavuta kupunduka, komanso mawonekedwe apamwamba kuposa ma elekitirodi amkuwa.
Kuipa kwa zinthu za graphite ndizomwe siziyenera kukonzedwa bwino pansi pa VDI12 (Ra0.4 m), komanso kugwiritsa ntchito bwino kwa edM kupanga electrode kumakhala kochepa.
Komabe, kuchokera ku mfundo zothandiza, chimodzi mwa zifukwa zofunika kwambiri kupititsa patsogolo Kukwezeleza zipangizo graphite ku China ndi kuti makina apadera graphite processing chofunika mphero maelekitirodi, amene amaika patsogolo zofunika zatsopano processing zida mabizinesi nkhungu, ena mabizinesi ang'onoang'ono. mwina alibe chikhalidwe ichi.
Nthawi zambiri, ubwino wa ma electrode a graphite umakhudza nthawi zambiri za edM processing, ndipo ndizoyenera kutchuka ndi kuzigwiritsa ntchito, ndi phindu lokhalitsa.Kuperewera kwa kukonza bwino pamtunda kungapangidwe pogwiritsa ntchito ma electrode amkuwa.
2.Kusankhidwa kwa graphite electrode zipangizo za EDM
Pazinthu za graphite, pali zizindikiro zinayi zotsatirazi zomwe zimatsimikizira momwe zinthuzo zikuyendera:
1) Avereji tinthu awiri a zinthu
The pafupifupi tinthu awiri a zinthu mwachindunji zimakhudza kumaliseche chikhalidwe cha zinthu.
Zing'onozing'ono za tinthu tating'onoting'ono ta graphite ndizomwe zimakhala zofanana kwambiri, zomwe zimatuluka zimakhala zokhazikika, zimakhala bwino komanso zimakhala zotsika kwambiri.
Zokulirapo za kukula kwa tinthu tating'onoting'ono, kutsika kwabwinoko kutha kupezedwa mukupanga makina ovuta, koma zotsatira zakumapeto ndizosauka komanso kuwonongeka kwa elekitirodi ndi kwakukulu.
2) Mphamvu yopindika ya zinthu
Mphamvu yosinthasintha ya chinthu ndikuwonetseratu mphamvu zake, kusonyeza kulimba kwa mkati mwake.
Zinthu zokhala ndi mphamvu zambiri zimakhala ndi ntchito yabwino yokana kutulutsa.Kwa electrode yolondola kwambiri, zinthu zomwe zili ndi mphamvu zabwino ziyenera kusankhidwa momwe zingathere.
3) Kuuma kwa m'mphepete mwa zinthu
Graphite ndi yolimba kuposa zida zachitsulo, ndipo kutayika kwa chida chodulira ndi chachikulu kuposa chitsulo chodula.
Pa nthawi yomweyo, kuuma mkulu wa graphite zakuthupi mu kumaliseche kutayika ulamuliro bwino.
4) Kukhazikika kwachilengedwe kwazinthuzo
Kutulutsa kwa zinthu za graphite zokhala ndi zopinga zapamwamba kudzakhala pang'onopang'ono kusiyana ndi kutsika kwa resistivity.
Kukwera kwa resistivity yachibadwa, kumachepetsa kutayika kwa electrode, koma kumtunda kwa resistivity yachibadwa, kukhazikika kwa kutulutsa kumakhudzidwa.
Pakali pano, pali mitundu yosiyanasiyana ya ma graphite yomwe ikupezeka kuchokera kwa otsogola padziko lonse lapansi opanga ma graphite.
Nthawi zambiri malinga ndi pafupifupi tinthu awiri a zipangizo graphite kuti wachinsinsi, tinthu m'mimba mwake ≤ 4 mamita limatanthauzidwa ngati zabwino graphite, particles mu 5 ~ 10 mamita limatanthauzidwa ngati sing'anga graphite, particles mu 10 mamita pamwamba limatchedwa coarse graphite.
Zing'onozing'ono za tinthu tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono tating'ono timatha kusankhidwa molingana ndi zofunikira ndi mtengo wa EDM.
3.Kupanga electrode ya graphite
Ma electrode a graphite amapangidwa makamaka ndi mphero.
Kuchokera pamalingaliro aukadaulo waukadaulo, ma graphite ndi mkuwa ndi zida ziwiri zosiyana, ndipo mawonekedwe awo odulidwa ayenera kuphunzitsidwa bwino.
Ngati graphite elekitirodi kukonzedwa ndi ndondomeko mkuwa elekitirodi, mavuto mosalephera kuchitika, monga pafupipafupi fracture ya pepala, amene amafuna kugwiritsa ntchito zipangizo zoyenera kudula ndi magawo kudula.
Machining graphite elekitirodi kuposa mkuwa elekitirodi chida kuvala, pa nkhani zachuma, kusankha carbide chida ndicho chuma kwambiri, kusankha diamondi ❖ kuyanika chida (chotchedwa graphite mpeni) mtengo ndi okwera mtengo, koma diamondi ❖ kuyanika chida moyo wautali utumiki, mkulu processing mwatsatanetsatane, phindu lonse lazachuma ndilabwino.
Kukula kwa mbali yakutsogolo ya chida kumakhudzanso moyo wake wautumiki, 0 ° kutsogolo kwa chipangizocho kudzakhala mpaka 50% kuposa 15 ° kutsogolo kwa moyo wautumiki wa chida, kukhazikika kumakhalanso bwino, koma chachikulu Angle, bwino Machining pamwamba, ntchito 15 ° Angle chida akhoza kukwaniritsa bwino Machining pamwamba.
Liwiro kudula mu Machining akhoza kusinthidwa malinga ndi mawonekedwe a elekitirodi, kawirikawiri 10m/mphindi, ofanana Machining a aluminiyamu kapena pulasitiki, kudula chida akhoza mwachindunji pa ndi kuchoka workpiece mu Machining akhakula, ndi chodabwitsa cha Angle. kugwa ndi kugawikana n'zosavuta kuchitika pomaliza Machining, ndi njira kuwala mpeni kuyenda mofulumira nthawi zambiri anatengera.
Graphite elekitirodi mu kudula ndondomeko adzabala fumbi kwambiri, pofuna kupewa graphite particles anakokera makina opota ndi wononga, pali njira ziwiri zazikulu pakali pano, mmodzi ndi ntchito yapadera graphite processing makina, winayo ndi wamba processing likulu. refit, yokhala ndi chipangizo chapadera chosonkhanitsira fumbi.
Makina apadera a graphite high speed mphero pamsika ali ndi mphamvu zambiri za mphero ndipo amatha kumaliza mosavuta kupanga maelekitirodi ovuta ndi olondola kwambiri komanso abwino pamwamba.
Ngati EDM ikufunika kupanga electrode ya graphite, tikulimbikitsidwa kugwiritsa ntchito zinthu zabwino za graphite ndi tinthu tating'onoting'ono.
Makina opangira ma graphite ndi osauka, momwe tinthu tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'onoting'ono tating'ono tating'onoting'ono monga kuthyola waya pafupipafupi komanso m'mphepete mwake kumatha kupewedwa.
4.EDM magawo a graphite electrode
Kusankhidwa kwa magawo a EDM a graphite ndi mkuwa ndi osiyana kwambiri.
Magawo a EDM makamaka akuphatikizapo panopa, pulse width, pulse gap ndi polarity.
Zotsatirazi zikufotokoza maziko ogwiritsira ntchito mwanzeru magawo akuluwa.
Kachulukidwe kakachulukidwe ka ma elekitirodi a graphite nthawi zambiri amakhala 10 ~ 12 A/cm2, okulirapo kuposa a elekitirodi yamkuwa.Choncho, m'kati mwazomwe zimaloledwa m'dera lofananirako, kukula kwamakono kumasankhidwa, mofulumira kuthamanga kwa graphite kutayika kwachangu kudzakhala, kuchepa kwa electrode kudzakhala kochepa, koma kuuma kwapamwamba kudzakhala kokulirapo.
Kukula kwake kwa pulse ndiko, kuchepa kwa electrode kudzakhala kochepa.
Komabe, kugunda kwamphamvu kokulirapo kumapangitsa kuti kukhazikika kwadongosolo kukhale koipitsitsa, komanso kuthamanga kwapang'onopang'ono komanso kukulirapo.
Pofuna kuonetsetsa kuti ma elekitirodi atayika pang'onopang'ono panthawi yokonza movutikira, kugunda kwamphamvu kwambiri kumagwiritsidwa ntchito, komwe kumatha kuzindikira kutayika kochepa kwa ma elekitirodi a graphite pomwe mtengo uli pakati pa 100 ndi 300 US.
Kuti mupeze zotsatira zabwino komanso zosasunthika za kutulutsa, m'lifupi mwake muyenera kusankhidwa.
Nthawi zambiri, kugunda m'lifupi mwa elekitirodi graphite ndi pafupifupi 40% zochepa kuposa mkuwa elekitirodi.
The zimachitika kusiyana makamaka zimakhudza kumaliseche Machining liwiro ndi Machining bata.Mtengo wokulirapo, m'pamenenso kukhazikika kwa makinawo kudzakhala kothandiza, zomwe zimathandiza kuti pakhale kufanana kwapamwamba, koma liwiro la makina lidzachepetsedwa.
Pansi pa chikhalidwe chowonetsetsa kuti kukhazikika kwazitsulo, kuwonjezereka kwapamwamba kungathe kupezedwa posankha kusiyana kochepa, koma pamene dziko lotulutsa liri losasunthika, kugwiritsira ntchito kwapamwamba kungathe kupezedwa posankha kusiyana kwakukulu kwa pulse.
Mu graphite elekitirodi kumaliseche Machining, zimachitika kusiyana ndi zimachitika m'lifupi nthawi zambiri amakhala pa 1: 1, pamene mkuwa ma elekitirodi Machining, kugunda kusiyana ndi zimachitika m'lifupi zimayikidwa pa 1:3.
Pansi pa khola la graphite processing, chiŵerengero chofananira pakati pa kugunda kwapakati ndi kugunda kwapakati kungasinthidwe kukhala 2: 3.
Pankhani ya kugunda kwazing'ono, ndizopindulitsa kupanga chophimba chophimba pamwamba pa electrode, zomwe zimathandiza kuchepetsa kutaya kwa electrode.
Kusankhidwa kwa polarity kwa graphite electrode mu EDM kumakhala kofanana ndi electrode yamkuwa.
Malinga ndi zotsatira za polarity za EDM, makina abwino a polarity amagwiritsidwa ntchito popanga zitsulo zakufa, ndiko kuti, electrode imagwirizanitsidwa ndi mtengo wabwino wamagetsi, ndipo chogwiritsira ntchito chimagwirizanitsidwa ndi pulasitiki yoipa ya magetsi.
Pogwiritsa ntchito kukula kwakukulu kwamakono ndi kugunda, kusankha makina abwino a polarity amatha kutaya kwambiri ma electrode.Ngati polarity ndiyolakwika, kutayika kwa electrode kumakhala kwakukulu kwambiri.
Pokhapokha pamene pamwamba pakufunika kukonzedwa bwino zosakwana VDI18 (Ra0.8 m) ndi kugunda m'lifupi ndi laling'ono kwambiri, ndi zoipa polarity processing ntchito kupeza bwino pamwamba khalidwe, koma electrode imfa ndi lalikulu.
Tsopano zida zamakina a CNC edM zili ndi magawo opangira ma graphite discharge.
Kugwiritsiridwa ntchito kwa magawo amagetsi ndikwanzeru ndipo kungapangidwe kokha ndi katswiri wa makina opangira makina.
Nthawi zambiri, makina akhoza sintha wokometsedwa processing magawo posankha zinthu ziwiri, mtundu ntchito, pamwamba roughness mtengo ndi inputting malo processing, processing kuya, electrode kukula makulitsidwe, etc. Pa mapulogalamu.
Anakhazikitsa graphite elekitirodi wa edm makina chida laibulale wolemera processing magawo, mtundu zakuthupi angasankhe mu coarse graphite, graphite, graphite limafanana zosiyanasiyana workpiece zakuthupi, kugawa mtundu ntchito kwa muyezo, poyambira, lakuthwa mfundo, lalikulu. m'dera, patsekeke lalikulu, monga chabwino, amaperekanso imfa otsika, muyezo, dzuwa mkulu ndi zina zotero mitundu yambiri processing patsogolo kusankha.
5.Mapeto
Zatsopano za graphite elekitirodi ndizofunikira kutchuka mwamphamvu ndipo zabwino zake zidzazindikirika pang'onopang'ono ndikuvomerezedwa ndi makampani opanga nkhungu zoweta.
Kusankhidwa koyenera kwa zida za graphite electrode ndikuwongolera maulalo okhudzana ndiukadaulo kudzabweretsa magwiridwe antchito apamwamba, apamwamba kwambiri komanso phindu lotsika mtengo kwa mabizinesi opanga nkhungu.
Nthawi yotumiza: Dec-04-2020