Nto tiav hauv CNC tig ua haujlwm
1. Hom Nto Roughness Achievable
CNC tig ua ntau yam ntawm nto tiav nyob ntawm cov cuab yeej, tsis, thiab cov khoom siv. Rough tig rau cov khoom tshem tawm feem ntau ua tiav qhov roughness ntawm 1.6 thiab 6.3 micrometers Ra, tawm hauv qhov pom pom cov cim thiab yuav tsum tau ua tiav tom ntej rau kev siv precision. General precision tig nrog cov qauv ntxig thiab cov qauv tsis sib xws yields 0.8 mus rau 1.6 micrometers Ra, haum rau feem ntau cov khoom sib dhos thiab tsis yog - qhov tseem ceeb haum. Zoo tig siv polished inserts, optimized geometry, thiab rigid setups ncav cuag 0.4 mus rau 0.8 micrometers Ra, tsim nyog rau bearing rooj thiab sealing nto. Siab-precision tig nrog pob zeb diamond-tipped los yog ua tib zoo npaj cov cuab yeej carbide, pub tsawg tsawg, thiab cov xwm txheej ruaj khov tuaj yeem ua tiav 0.2 txog 0.4 micrometers Ra. Ultra-precision tig ua haujlwm ib leeg- siv lead ua pob zeb diamond cov cuab yeej ntawm cov khoom tsis yog-ferrous cov khoom tsim kho qhov muag- qhov chaw zoo hauv qab 0.1 micrometers Ra, nrog rau kev teeb tsa tshwj xeeb txog 0.01 micrometers lossis zoo dua.
2. Theoretical Surface Roughness Foundation
Lub ncov theoretical - mus rau - hav roughness nyob rau hauv txoj siav yog feem ntau los ntawm cov geometric kev sib cuam tshuam ntawm lub qhov ntswg vojvoog thiab pub tus nqi. Cov kev sib raug zoo tseem ceeb qhia txog qhov kev xav ntawm qhov siab qhov siab raws li kwv yees li pub squared faib los ntawm yim lub qhov ntswg vojvoog. Qhov no txhais tau tias ob npaug ntawm tus nqi pub quadruples theoretical roughness, thaum ob npaug ntawm lub qhov ntswg radius halves nws. Nyob rau hauv kev xyaum, qhov tseeb roughness tshaj qhov theoretical qhov tseem ceeb vim yog ua - nce ntug tsim, cov cuab yeej vibration, cov ntaub ntawv sab ntws, thiab tshuab dynamics. Tus qauv theoretical muab ib lub hauv paus rau kev xaiv parameter tab sis yuav tsum muaj kev lees paub qhov tseeb rau qhov chaw tseem ceeb.
3. Qhov tseem ceeb Parameter cuam tshuam rau saum npoo tiav
Pub tus nqi stands raws li qhov tseem ceeb parameter cuam tshuam qhov kev ntxhib los mos ntawm qhov chaw. Txo tus nqi noj ntawm 0.3 mus rau 0.1 millimeters ib kiv puag ncig feem ntau txhim kho nto roughness los ntawm ib qho ntawm peb mus rau tsib. Txawm li cas los xij, cov khoom noj uas tsis tshua muaj ntau dhau ua rau rub tawm es tsis yog txiav, ua kom sov thiab ua haujlwm - hardening yam tsis txhim kho tiav. Cov tswv yim tsawg kawg nkaus yog nyob ntawm cov cuab yeej ntse thiab cov khoom siv, feem ntau tsis poob qis dua 0.02 millimeters ib kiv puag ncig rau cov cuab yeej carbide.
Txiav ceev cuam tshuam rau saum npoo tiav los ntawm nws txoj kev cuam tshuam ntawm kev tsim- nce ntug. Ntawm qhov nrawm nrawm, cov khoom siv ua haujlwm ua raws li cov cuab yeej taw qhia, tsim cov khoom tsis sib xws uas rhuav tshem qhov chaw thiab tsim cov khoom ntxhib. Raws li kev ceev nce, ua - nce ntug txo qis thiab ua kom tiav kom zoo kom txog thaum muaj ntau yam zoo. Rau aluminium alloys qhov kev pom zoo no feem ntau spans 300 txog 800 meters ib feeb, thaum steels xav tau 150 mus rau 400 meters ib feeb nyob ntawm cov ntsiab lus alloy. Kev nrawm dhau ua kom muaj cua sov ntau dhau, ua kom cov cuab yeej siv nrawm dua thiab ua kom tiav qhov kawg.
Qhov tob ntawm kev txiav cuam tshuam tiav los ntawm nws cov nyhuv ntawm kev txiav quab yuam thiab lub cev deflection. Roughing qhov tob ntawm 2 mus rau 5 millimeters ua ntej muab cov khoom tshem tawm tshaj qhov zoo. Kev ua tiav qhov tob yuav tsum tau txo qis rau 0.1 txog 0.5 millimeter kom txo qis radial txiav quab yuam uas deflect slender workpieces los yog cov cuab yeej hloov tau yooj yim. Kev ua tiav lub teeb heev dhau qis dua 0.05 millimeter tuaj yeem caij ua haujlwm- txheej tawv tawv los ntawm kev dhau los dhau los es tsis tsim cov npoo tshiab, ua rau cov txiaj ntsig tsis zoo.
4. Cov cuab yeej Geometry thiab cov khoom xaiv
Lub qhov ntswg radius ncaj qha txiav txim siab theoretical roughness thiab lub zog lub cuab yeej. Cov kab hluav taws xob me me ntawm 0.4 txog 0.8 millimeter tsim cov txheej txheem theoretical tiav tab sis ua rau cov cuab yeej tsis muaj zog thiab ua rau muaj kev pheej hmoo siab. Loj radii ntawm 1.2 mus rau 2.4 millimeters kis tau txiav quab yuam ntev dua arcs, txhim kho tiav thiab lub neej cuab yeej tab sis yuav tsum tau siv lub tshuab ntau zog thiab rigidity. Cov kev xaiv sib npaug ua tiav cov kev cai tiv thaiv nti tswj thiab cov cuab yeej ua haujlwm ntev.
Lub kaum sab xis cuam tshuam txiav quab yuam thiab nti ntws. Qhov zoo rake kaum ntawm 5 txog 15 degrees txo kev txiav quab yuam thiab txhim kho nto tiav ntawm cov ntaub ntawv zoo li txhuas thiab tooj liab. Qhov tsis zoo rake cov ces kaum nce lub zog ntawm cov ntaub ntawv nyuaj tab sis tsim kom muaj zog ntau dua thiab rougher nto. Nruab nrab rau me ntsis zoo rakes haum dav dav - lub hom phiaj steel tig.
Kev xaiv cov khoom siv cuam tshuam cuam tshuam qhov ua tiav thiab sib xws. Uncoated carbide nrog cov npoo ntse muab kev ua tiav zoo ntawm txhuas thiab cov khoom tsis yog-ferrous. Coated carbides nrog titanium aluminium nitride los yog coatings zoo sib xws txuas lub neej ntawm cov hlau thiab stainless hlau, tab sis tej zaum yuav cuam tshuam me ntsis ntug sharpness. Ceramic inserts kov siab - nrawm nrawm tab sis tsis tshua muaj kev ua tiav zoo hauv qab 0.4 micrometers Ra. Cubic boron nitride cov cuab yeej ua kom muaj zog tig ntawm cov hlau tawv tawv nrog kev ua tiav mus txog kev sib tsoo zoo. Polycrystalline pob zeb diamond cov cuab yeej tsim daim iav tiav ntawm txhuas, tooj liab, thiab cov khoom sib xyaw tab sis tsis tsim nyog rau cov ntaub ntawv ferrous vim kev siv tshuaj lom neeg.
Cov cuab yeej kho mob ua pov thawj tseem ceeb rau kev ua tiav zoo ib yam. Cov cuab yeej hnav tsim kom loj qhov ntswg radii, qhov tsis zoo ntawm ntug profile, thiab ua tau -txoj kev nyiam ntawm ntug uas ua rau cov khoom tsis zoo. Kev tshuaj xyuas tsis tu ncua thiab teem sijhawm hloov pauv raws li lub sijhawm txiav los yog saib xyuas flank hnav khaws cia ua tiav lub peev xwm.
5. Kev txiav txim siab ntawm cov khoom siv ua haujlwm
Cov khoom siv tsim tsim cov kev txwv qhov kawg rau kev ua haujlwm tig. Dawb-machining steels nrog ntxiv sulfur los yog lead inclusions tawg chips yooj yim thiab tshuab rau 0.8 mus rau 1.6 micrometers Ra nrog cov qauv tsis. Austenitic stainless hlau ua haujlwm- tawv sai thiab xav tau ntse, zoo- rake cov cuab yeej nrog cov tsis sib xws los tiv thaiv qhov tawg; tiav hauv qab 1.6 micrometers Ra thov ceev faj optimization. Aluminium alloys tshuab tshwj xeeb zoo, nrog cov qib wrought zoo li 6061 thiab 7075 ib txwm ua tiav 0.4 txog 0.8 micrometers Ra thiab muaj peev xwm ntawm 0.2 micrometers nrog cov tsis zoo. Cam khwb cia txhuas alloys nrog silicon cov ntsiab lus nthuav tawm tus cwj pwm abrasive uas ua kom cov cuab yeej hnav thiab txwv kev ua tiav zoo. Titanium alloys tsim kom muaj qhov kub thiab txias thiab xav tau qeeb qeeb nrog kev teeb tsa nruj; ua tiav hauv qab 0.8 micrometers Ra sib tw cov pa tig. tooj liab thiab tooj dag muab kev ua haujlwm zoo heev thiab tuaj yeem ua tiav daim iav-zoo li tiav nrog cov cuab yeej pob zeb diamond.
6. Lub tshuab txias thiab ruaj khov
Spindle runout yuav tsum tau tswj hauv qab 2 micrometers rau kev ua tiav, raws li txhua qhov eccentricity txhais ncaj qha rau hauv qhov sib txawv ntawm qhov profile. Bearing mob, txoj siv tawv nruj, thiab spindle tshuav nyiaj li cas tag nrho cov kev ua tiav tiav. Lub tshuab rigidity nrog rau lub txaj txhav, swb kev sib dhos, thiab kev txhawb nqa tailstock tiv thaiv kev co -induced chatter marks uas rhuav tshem qhov zoo. Thermal stability los ntawm kev tswj ib puag ncig qhov kub thiab txias ntxaiv tswj qhov sib xws ntawm qhov sib xws thaum txuas txuas ntxiv.
7. Cov tswv yim Coolant thiab lubrication
Daim ntawv thov dej nyab los ntawm kev tswj qhov kub thiab txias tshem tawm cov chips, dissipates cua sov, thiab tiv thaiv kev tsim - nce ntug. Rau txhuas thiab tooj liab, qhov kub thiab txias yuav tsum ua kom haum rau qhov chaw nyob ib puag ncig kom tsis txhob muaj qhov cuam tshuam ntawm thermal shock. High-siab coolant los ntawm cov khoom xa tuaj txhim kho nti tawg thiab khiav tawm hauv qhov tob tob thiab kev ua haujlwm grooving. Qhov tsawg kawg nkaus kom muaj nuj nqis lubrication systems txo cov coolant noj thaum muab txaus lubrication rau tag tig ntawm steels. Rau qee qhov kev siv, qhuav tig nrog compressed cua nti tshem tawm tiv thaiv thermal gradients txuam nrog kua coolant, tab sis qhov no ua rau cov cuab yeej hnav cov nqi.
8. Cov txheej txheem txheej txheem rau kev ua tiav tiav
Spark-tawm cov ntawv hla dhau suav nrog kev khiav qhov kawg dhau ntawm xoom lossis tsawg kawg pub rau hlawv qhov chaw yam tsis muaj kev txiav, txo cov khoom seem seem ntawm 20 mus rau 40 feem pua. Cov txheej txheem no yuav tsum muaj kev teeb tsa nruj kom tsis txhob rub tawm -vim kev co. Polishing tig ntiav cov cuab yeej tshwj xeeb npaj nrog cov radii loj thiab siab zoo rake ces kaum ntawm qhov qis heev los tsim qhov chaw kub hnyiab mus txog 0.1 micrometers Ra. Hard tig nrog cubic boron nitride cov cuab yeej ntawm hardened steels saum 50 HRC ua tiav ntawm 0.4 mus rau 0.8 micrometers Ra, muaj peev xwm tshem tawm kev sib tsoo. Vibratory tig siv ultrasonic lossis qis- zaus cov cuab yeej oscillation hloov cov chip tsim thiab tuaj yeem txhim kho qhov kev ncaj ncees ntawm cov ntaub ntawv nyuaj.
9. Kev Ntsuas thiab Kev Tswj Xyuas Zoo
Kev ntsuas qhov ua tiav hauv kev tig feem ntau yog siv cov stylus profileometers tracing perpendicular rau cov cim pub. Kev ntsuas qhov chaw yuav tsum tsis txhob hloov chaw, cov cuab yeej nkag, thiab cov cheeb tsam sib tham. Rau qhov chaw tig nrog cov lus qhia kev ntxhib los mos, kev ntsuas kev ntsuas cuam tshuam rau kev nyeem ntawv; perpendicular ntsuas captures tag nrho feed mark profile thaum uas tig mus ntsuas yuav underestimate roughness. Cov txheej txheem kev txheeb cais tswj kev taug qab ntawm qhov chaw ua tiav thoob plaws cov khoom tsim khoom txheeb xyuas cov cuab yeej hnav tiam sis thiab qhov ntsuas tsis pom ua ntej tawm - ntawm - qhov tshwj xeeb tshwm sim.
10. Kev daws teeb meem kev ua tiav tag nrho
Pub cov cim coarser tshaj qhov kev kwv yees kwv yees qhia tias pub ntau dhau, lub qhov ntswg tsis txaus, lossis cov cuab yeej deflection hauv qab txiav quab yuam. Ua-liab ntug manifests li torn, irregular nto zoo nkauj nrog cov khoom deposits; nce txiav ceev lossis txhim kho kev xa khoom txias feem ntau daws qhov no. Chatter tsim cov waviness tsis tu ncua perpendicular rau cov kev coj noj coj ua, yuav tsum tau nce lub zog rigidity, kho ceev kom tsis txhob resonant zaus, los yog txo qhov tob ntawm kev txiav. Taper lossis dimensional variation raws qhov ntev qhia tias workpiece deflection los ntawm kev txiav ntau dhau los yog tsis txaus tailstock txhawb. Nto tearing nyob rau hauv cov ntaub ntawv ductile tshwm sim los ntawm qhov tsis zoo rake ces kaum, dull cov cuab yeej, los yog tsis txaus txiav ceev.
Xaus
CNC tig muaj peev xwm ua tiav qhov kawg ntawm kev ua haujlwm ntxhib ntawm 6.3 micrometers Ra mus rau ultra- qhov tseeb daim iav nto hauv qab 0.1 micrometers Ra. Qhov ua tiav tiav yog nyob ntawm kev sib xyaw ua kom zoo ntawm cov khoom noj, txiav ceev, qhov tob ntawm kev txiav, cov cuab yeej geometry thiab cov khoom siv, cov yam ntxwv ntawm lub tshuab, lub tshuab ua haujlwm, thiab lub tswv yim coolant. Kev nkag siab txog cov hauv paus ntsiab lus theoretical thiab kev sib cuam tshuam ntawm cov kev hloov pauv no ua rau cov txheej txheem engineers xaiv cov kev sib txuas tsim nyog uas ua tau raws li qhov yuav tsum tau ua thaum tswj kev lag luam tsim khoom. Rau cov ntawv thov kom raug, kev nqis peev hauv siab - cov cuab yeej zoo, kev teeb tsa nruj, thiab kev tswj hwm ib puag ncig zoo ib yam ua rau muaj kev ncaj ncees ntawm qhov chaw zoo dua piv rau qhov tsis zoo nrog cov cuab yeej marginal.
