Kev ua graphite tuaj yeem yog kev lag luam tsis yooj yim, yog li muab qee qhov teeb meem ua ntej yog qhov tseem ceeb rau kev tsim khoom thiab kev muaj txiaj ntsig.
Qhov tseeb tau ua pov thawj tias graphite yog qhov nyuaj rau tshuab, tshwj xeeb tshaj yog rau EDM electrodes uas yuav tsum tau ua kom zoo tshaj plaws thiab cov qauv sib xws.Nov yog tsib lub ntsiab lus tseem ceeb uas yuav tsum nco ntsoov thaum siv graphite:
Graphite qib yog qhov pom kev nyuaj rau kev paub qhov txawv, tab sis txhua tus muaj lub cev tshwj xeeb thiab kev ua tau zoo.Graphite qib tau muab faib ua rau pawg raws li qhov nruab nrab particle loj, tab sis tsuas yog peb pawg me me (particle loj ntawm 10 microns lossis tsawg dua) feem ntau siv hauv EDM niaj hnub.Qhov qeb duas hauv kev faib tawm yog qhov qhia txog kev siv tau thiab kev ua tau zoo.
Raws li ib tsab xov xwm los ntawm Doug Garda (Toyo Tanso, uas tau sau rau peb tus viv ncaus luam tawm "MoldMaking Technology" thaum lub sijhawm, tab sis tam sim no nws yog SGL Carbon), qib nrog qhov loj me ntawm 8 txog 10 microns yog siv rau roughing.Tsawg dua qhov tiav thiab nthuav dav daim ntawv thov siv qib ntawm 5 txog 8 micron particle loj.Electrodes ua los ntawm cov qib no feem ntau yog siv los ua forging pwm thiab tuag-casting pwm, los yog kom tsis tshua muaj hmoov thiab sintered hlau daim ntaub ntawv.
Kev nthuav dav tsim thiab me me, cov yam ntxwv zoo dua yog qhov tsim nyog rau qhov ntau thiab tsawg ntawm 3 txog 5 microns.Electrode daim ntaub ntawv nyob rau hauv no ntau yam xws li hlau txiav thiab aerospace.
Ultra-fine precision electrodes siv cov qib graphite nrog qhov loj me ntawm 1 txog 3 microns feem ntau xav tau rau cov ntawv thov tshwj xeeb aerospace hlau thiab carbide.
Thaum sau ib tsab xov xwm rau MMT, Jerry Mercer ntawm Poco Cov Khoom Siv tau txheeb xyuas qhov loj me, khoov lub zog, thiab Shore hardness raws li peb qhov tseem ceeb ntawm kev ua haujlwm thaum lub sij hawm ua electrode.Txawm li cas los xij, microstructure ntawm graphite feem ntau yog qhov txwv tsis pub ua haujlwm ntawm cov electrode thaum lub sijhawm ua haujlwm EDM kawg.
Hauv lwm tsab xov xwm MMT, Mercer tau hais tias lub zog khoov yuav tsum siab dua 13,000 psi kom ntseeg tau tias graphite tuaj yeem ua tiav rau hauv cov tav sib sib zog nqus thiab nyias yam tsis muaj kev tawg.Cov txheej txheem tsim khoom ntawm graphite electrodes yog ntev thiab tej zaum yuav xav tau cov ncauj lus kom ntxaws, nyuaj-rau-tsim tshuab, yog li ua kom ruaj khov zoo li qhov no yuav pab txo cov nqi.
Shore hardness ntsuas lub workability ntawm graphite qib.Mercer ceeb toom tias cov qib graphite uas muag muag heev tuaj yeem cuam tshuam cov cuab yeej siv, ua kom cov txheej txheem ua haujlwm qeeb lossis ua rau lub qhov nrog cov plua plav, yog li tso siab rau ntawm phab ntsa ntawm lub qhov.Hauv cov xwm txheej no, txo qhov pub thiab ceev tuaj yeem tiv thaiv qhov tsis raug, tab sis nws yuav ua rau lub sijhawm ua haujlwm ntau ntxiv.Thaum ua tiav, qhov nyuaj, me me-grained graphite tuaj yeem ua rau cov khoom ntawm ntug ntawm lub qhov tawg.Cov ntaub ntawv no kuj tseem tuaj yeem ua rau cov cuab yeej abrasive heev, ua rau hnav, uas cuam tshuam rau kev ncaj ncees ntawm lub qhov taub thiab nce nqi ua haujlwm.Feem ntau, kom tsis txhob deflection ntawm qhov siab hardness qhov tseem ceeb, nws yog ib qho tsim nyog yuav tsum tau txo cov khoom noj thiab ceev ntawm txhua qhov taw tes nrog Shore hardness siab dua 80 los ntawm 1%.
Vim hais tias ntawm txoj kev uas EDM tsim ib daim iav duab ntawm cov electrode nyob rau hauv cov txheej txheem, Mercer kuj tau hais tias ib tug nruj packed, uniform microstructure yog qhov tseem ceeb rau graphite electrodes.Tsis sib npaug particle ciam teb nce porosity, yog li nce particle yaig thiab accelerating electrode tsis ua hauj lwm.Thaum lub sij hawm thawj electrode machining txheej txheem, qhov tsis sib xws microstructure kuj tuaj yeem ua rau qhov tsis sib xws ntawm qhov chaw tiav-qhov teeb meem no tseem ceeb dua ntawm cov chaw ua haujlwm siab ceev.Cov pob tawv tawv hauv cov graphite kuj tuaj yeem ua rau lub cuab yeej deflect, ua rau cov electrode zaum kawg tawm ntawm qhov tshwj xeeb.Qhov deflection no yuav yog me ntsis txaus tias lub qhov oblique tshwm ncaj nraim ntawm qhov nkag.
Muaj cov tshuab ua graphite tshwj xeeb.Txawm hais tias cov cav tov no yuav ua kom ntau lawm, lawv tsis yog tib lub tshuab uas manufacturers siv tau.Ntxiv nrog rau kev tswj cov plua plav (tshwj xeeb tom qab hauv tsab xov xwm), cov ntawv MMS yav dhau los kuj tau tshaj tawm cov txiaj ntsig ntawm cov tshuab nrog ceev spindles thiab tswj nrog kev ua haujlwm siab rau graphite manufacturing.Qhov zoo tshaj plaws, kev tswj hwm sai yuav tsum muaj cov yam ntxwv saib yav tom ntej, thiab cov neeg siv yuav tsum siv cov cuab yeej ua kom zoo dua software.
Thaum impregnating graphite electrodes - uas yog, sau lub pores ntawm graphite microstructure nrog micron-loj hais - Garda pom zoo kom siv tooj liab vim nws muaj peev xwm stably txheej txheem tshwj xeeb tooj liab thiab npib tsib xee alloys, xws li cov siv nyob rau hauv aerospace daim ntaub ntawv.Copper impregnated graphite qib ua tiav zoo dua li cov qib uas tsis yog-impregnated ntawm tib qhov kev faib tawm.Lawv tuaj yeem ua tiav kev ua haujlwm ruaj khov thaum ua haujlwm nyob rau hauv cov xwm txheej tsis zoo xws li dej ntws tsis zoo lossis cov neeg ua haujlwm tsis muaj kev paub.
Raws li Mercer tsab xov xwm thib peb, txawm hais tias hluavtaws graphite-cov khoom siv los ua EDM electrodes-yog kev lom neeg tsis muaj zog thiab yog li thawj zaug tsis muaj teeb meem rau tib neeg dua li lwm cov ntaub ntawv, qhov cua tsis zoo tuaj yeem ua rau muaj teeb meem.Synthetic graphite yog cov khoom siv hluav taws xob, uas tuaj yeem ua rau qee qhov teeb meem rau lub cuab yeej, uas yuav ua rau luv luv thaum nws los ntawm kev sib cuag nrog cov khoom siv txawv teb chaws.Tsis tas li ntawd, graphite impregnated nrog cov ntaub ntawv xws li tooj liab thiab tungsten yuav tsum tau saib xyuas ntxiv.
Mercer piav qhia tias tib neeg lub qhov muag tsis tuaj yeem pom cov hmoov av graphite hauv cov ntsiab lus me me, tab sis nws tseem tuaj yeem ua rau khaus, tearing thiab liab.Kev sib cuag nrog cov plua plav yuav ua rau abrasive thiab khaus me ntsis, tab sis nws tsis zoo li yuav nqus tau.Lub sij hawm-weighted nruab nrab (TWA) raug cov lus qhia rau graphite hmoov av nyob rau hauv 8 teev yog 10 mg / m3, uas yog ib tug pom concentration thiab yuav tsis tshwm sim nyob rau hauv cov plua plav sau system siv.
Kev raug cov graphite plua plav ntev ntev tuaj yeem ua rau cov khoom nqus graphite nyob hauv lub ntsws thiab bronchi.Qhov no tuaj yeem ua rau mob hnyav pneumoconiosis hu ua kab mob graphite.Graphitization feem ntau muaj feem xyuam rau ntuj graphite, tab sis nyob rau hauv tsawg zaus nws muaj feem xyuam rau hluavtaws graphite.
Cov plua plav uas khaws cia hauv qhov chaw ua haujlwm yog qhov hluav taws kub heev, thiab (hauv tsab xov xwm thib plaub) Mercer hais tias nws tuaj yeem tawg tau raws li qee yam xwm txheej.Thaum lub ignition ntsib ib tug txaus concentration ntawm nplua hais raug tshem tawm nyob rau hauv cov huab cua, ib tug hmoov av hluav taws thiab deflagration yuav tshwm sim.Yog tias cov plua plav tawg mus rau hauv qhov loj lossis nyob hauv qhov chaw kaw, nws yuav tawg ntau dua.Kev tswj txhua yam khoom txaus ntshai (roj, oxygen, ignition, diffusion lossis txwv) tuaj yeem txo tau cov hmoov av tawg.Feem ntau, kev lag luam tsom rau roj los ntawm kev tshem cov plua plav tawm ntawm qhov chaw los ntawm qhov cua, tab sis cov khw muag khoom yuav tsum xav txog txhua yam kom ua tiav qhov kev nyab xeeb siab tshaj plaws.Cov khoom siv tswj cov plua plav yuav tsum muaj qhov tawg-pov thawj lossis tawg-pov thawj, lossis muab tso rau hauv qhov chaw tsis muaj oxygen.
Mercer tau txheeb xyuas ob txoj hauv kev los tswj cov graphite plua plav: kev kub ceev cua tshuab nrog cov khoom siv plua plav-uas tuaj yeem kho lossis txav tau raws li daim ntawv thov-thiab cov tshuab ntub dej uas ua rau thaj tsam ib ncig ntawm lub tshuab txiav nrog kua.
Cov khw muag khoom uas ua cov graphite me me tuaj yeem siv lub tshuab nqa tau nrog lub tshuab ua haujlwm siab (HEPA) lim uas tuaj yeem txav mus los ntawm cov tshuab.Txawm li cas los xij, cov kev cob qhia uas ua cov graphite ntau yuav tsum tau siv cov txheej txheem ruaj khov.Qhov tsawg kawg nkaus huab cua tshaj tawm los ntes cov plua plav yog 500 ko taw ib feeb, thiab qhov nrawm hauv cov kav dej nce mus rau tsawg kawg 2000 ko taw ib ob.
Cov tshuab ntub dej ua rau muaj kev pheej hmoo ntawm cov kua "wicking" (raug absorbed) rau hauv cov khoom siv electrode kom tshem tawm cov plua plav.Kev ua tsis tiav ntawm cov kua dej ua ntej tso cov electrode hauv EDM tuaj yeem ua rau muaj kev sib kis ntawm cov roj dielectric.Cov neeg khiav dej num yuav tsum siv cov kev daws teeb meem dej vim tias cov kev daws teeb meem no tsis tshua muaj kev nqus roj ntau dua li cov kev daws teeb meem roj.Kev ziab cov electrode ua ntej siv EDM feem ntau yog muab cov khoom tso rau hauv qhov cub convection rau li ib teev ntawm qhov kub me ntsis saum toj no evaporation point ntawm cov tshuaj.Qhov kub yuav tsum tsis pub tshaj 400 degrees, vim qhov no yuav oxidize thiab corrode cov khoom.Cov neeg ua haujlwm yuav tsum tsis txhob siv cov cua compressed kom qhuav cov electrode, vim hais tias cov huab cua siab tsuas yog yuam kom cov kua dej tob rau hauv cov qauv electrode.
Princeton Tool vam tias yuav nthuav dav nws cov khoom lag luam, ua rau nws muaj kev cuam tshuam rau West Coast, thiab dhau los ua tus neeg xa khoom muaj zog.Yuav kom ua tiav peb lub hom phiaj tib lub sijhawm, kev nrhiav tau ntawm lwm lub khw machining tau los ua qhov kev xaiv zoo tshaj plaws.
Cov hlau EDM tig cov kab rov tav coj electrode hlau nyob rau hauv CNC-tswj E axis, muab lub rooj cob qhia nrog workpiece clearance thiab yooj los tsim complex thiab high-precision PCD cov cuab yeej.
Post lub sij hawm: Sep-26-2021