Hobaneng ha Baenjiniere ba Khetha Li-Sintered Bearings: Molemo oa Powder Metallurgy
Saense e ka Mora ho Sintered Bronze Bearings
Saense ea tlhahiso ea li-bronze bearings e itšetlehile ka taolo e nepahetseng ea metallurgic e fetolang likaroloana tsa tšepe tse hlephileng hore e be likarolo tse sebetsang tse nang le porosity e entsoeng. Mokhoa ona o tsotehang o qala ka lisebelisoa tse tala 'me o qetella ka karolo e fanang ka lubrication e tsitsitseng bophelong bohle ba eona ba ho sebetsa.
Metallurgy ea phofo: Ho Fetola Metal ho Powder le Back
Metallurgy ea phofo e sebetsa e le motheo oa tlhahiso ea sintered, ho qala ka tlhahiso ea phofo ea tšepe. Baetsi ba sebelisa phofo ea boronse ea atomized e nang le koporo e nang le 9-11% tin. Phofo e tsoakoa le li-additives, ho kenyeletsoa litlolo tsa waxy tse thusang tšebetsong ea compaction. Motsoako ebe o fetela ka har'a compaction ea mochini ka har'a likhatello tse tlohang ho 200 ho isa ho 1,500 MPa ho ipapisitsoe le boholo bo lakatsehang ba ho qetela.
Karolo e "tala" e fetela ts'ebetsong ea sintering ka mor'a ho kopana. Potoloho ena ea mocheso e futhumatsa karolo e ka bang 820 ° C sebakeng se laoloang sa nitrogen le hydrogen (hangata ka karolelano ea 70:30). Thempereichara e lula e le ka tlas'a ntlha ea ho qhibiliha ea tšepe empa e fihla holimo ho lekana ho baka ho hasana ha boemo bo tiileng. Likaroloana tsa tšepe li kopana hammoho libakeng tsa ho kopana nakong ena ea bohlokoa 'me li etsa sebopeho se tiileng empa se le masoba se bolokang botsitso ba eona.
Microstructure ea Sintered Materials: Porosity ka Moralo
Sintered bronze bearings li na le porosity ea ka boomo e sebeletsang morero, ho fapana le litšepe tse tiileng. Li-bearings tsena hangata li na le porosity lipakeng tsa 15% le 25% ka molumo. Tšobotsi ena e arola thepa e sirelelitsoeng ho litšepe tse entsoeng ka tšepe 'me e ama mekhoa ea eona ea mochini, mocheso le ts'ebetso ka bongata.
The bearing's microstructure e na leli-pores tse hokahanengtse etsang marang-rang ho pholletsa le thepa. Marang-rang ana a lumella lubricant hore e tsamaee ka bolokolohi ka har'a mohaho oa ho jara. Litšobotsi tsa phofo, khatello ea compaction, le maemo a sintering a khetholla boholo le kabo ea li-pores tsena. Porosity e lula e "butsoe" ha e laoloa hantle, ho bolelang hore li-pores lia hokahana ho fapana le ho ba teng e le li-voids tse ka thoko.
The porosity e fokotsa matla a mochine ha a bapisoa le litšepe tse tiileng empa e etsa hore li-bearings tsena e be tsa bohlokoa ka ho etsa hore motho a itšepe.[2]. Baenjiniere ba ka fetola peresente ea porosity ho latela seo sesebelisoa se se hlokang, ho fumana tekanyo e nepahetseng lipakeng tsa matla le litlhoko tsa lubrication.
Oli Impregnation Process: Ho iketsetsa Boithapo
Boronse bo nang le porous bo fetela ka har'a ho kenngoa ha oli ka mor'a ho sintering. Ts'ebetso ena ea bohlokoa e e fetola karolo ea ho itlotsa. Sekhahla se kena ka likamoreng tsa vacuum moo moea o tlohang masobeng pele o qoelisoa ka oli e khethehileng. Oli e tlatsa bonyane 90% ea molumo o fumanehang oa pore ka ts'ebetso ea capillary.
Bearing e sebetsa ka mokhoa o ikhethileng oa ho lubrication nakong ea ts'ebetso. Mocheso o bakoang ke ho potoloha ha shaft khahlano le bokaholimo bo tsamaisang oli, o etsa hore oli e tsoe ka masobeng ho ea lebaleng la bearing shaft. Sena se etsa filimi e tšesaane ea ho tlotsa lipakeng tsa likarolo tse tsamaeang. Oli e khutlela pores ka ts'ebetso ea capillary ha ho hema ho pholile nakong ea ho se sebetse, ho boloka potoloho e tsoelang pele ea lubrication.[2].
Phallo ea oli e theha seo baenjiniere ba se bitsang "ketso ea ho pompa". Likarolo tse laetsoeng li lokolla oli nakong ea ts'ebetso ha libaka tse sa laoloang li e hula hape. Sena se theha tsamaiso e sa feleng ea lubrication e sebetsang ntle le tlhokomelo. Li-bearings tsena tse itšebetsang li ka sebetsa ka mokhoa o ts'epahalang lihora tse 3,000-5,000 ntle le ho hloka mafura a mangata.
Thepa ea Lintho Tse Ntlafatsang Ts'ebetso
Li-bearings tse sintered li fumana ts'ebetso ea tsona e ntle ho tsoa ho thepa e ikhethang e tsoang homokhoa oa tlhahiso ea phofo ea metallurgy. Mehaho ena e fa likarolo tsa sintered melemo e meholo ho feta lisebelisoa tse tloaelehileng kapa tse entsoeng ka mochini lits'ebetsong tse ngata.
Kabo ea Matla a Uniform vs. Cast Materials
Ts'ebetso ea metallurgy ea phofo e hlahisa melemo e metle ea sebopeho ho feta mekhoa ea khale ea ho lahla. Hangata likarolo tsa cast li na le mathata hobane lintho tse entsoeng ka alloy ha li pholile ka ho lekana. Sena se lebisa ho phapano ea matla, letsoalo, le thepa ea mocheso ho pholletsa le thepa. Sehlahisoa sa ho qetela se ka silafala ha tšepe e qhibilihisitsoeng e kopana le lisebelisoa tsa matsete nakong ea ho lahla.
Likarolo tse sintered li fapane. Li na le sebopeho se lekanang sethaleng se seng le se seng sa tlhahiso. Likaroloana tsa phofo tsa tšepe li hasana ka mokhoa o ts'oanang pele li kopana 'me li lula li le teng nakong ea sintering. Sena se theha microstructure e tsitsitseng e matla, e thata, le e sa khoneng ho apara ho pholletsa le karolo eohle.
Ts'ebetso ea sintering e fana ka taolo e betere holim'a microstructure ea thepa ho feta ho forging kapa casting. Lipatlisiso li bontšitse hore likarolo tse entsoeng hantle tse sintered li ka ba matla ka makhetlo a 2-10 ho feta tšepe e entsoeng ka tšepe. Matla a ka 'na a fokotseha ka lebaka la porosity, empa a ata ka ho lekana ho pholletsa le karolo. Sena se etsa hore ts'ebetso e tlas'a mojaro e lebeletsoe esale pele.
Dimensional Botsitso Tlas'a Mocheso Fluctuations
Li-bearings tse sintered li khanya haholo ha ho tluoa tabeng ea ho boloka sebōpeho sa tsona ka mocheso o fapaneng. Likarolo tsena li boloka mamello e tiileng ea mahlakore ka ho khopama ho fokolang ka lebaka la mokhoa oa tsona o ikhethang oa tlhahiso.
Lintlha tse peli tse ka sehloohong li baka botsitso bona. Li-pores li fana ka sebaka sa katoloso e nyane ea mocheso ntle le ho fetola litekanyo tse akaretsang. The microstructure ea junifomo e boetse e atoloha le ho etsa likonteraka ka mokhoa o ts'oanang ho feta lisebelisoa tse lahliloeng, tse thibelang ho loana le libaka tsa khatello ea maikutlo.
Botsitso bona bo thusa haholo ha mocheso o fetoha nakong ea tšebeliso. Mehlala ea aluminium oxide e honyela ka 17.6% nakong ea sintering ho 1600 ° C empa e ntse e boloka 98.3% ea boima ba 'mele ka botsitso bo boholo. Likarolo tsa tšepe li lula li nepahetse le ha li chesitsoe ka holimo ho 2500°F (1370°C) .
Ho nepahala ho betere ho tsoa ho li-additives tse laoloang. Silicon nitride e kenyellelitsoeng ho lisampole tse fetotsoeng tsa boron e thusa ho thibela ho sotha ho hoholo nakong ea sintering.
Apara Litšobotsi tsa Resistance tsa Li-Alloys tse Tloaelehileng
U ka fumana li-bearings tsa sintered ka metsoako e fapaneng ea alloy, e 'ngoe le e' ngoe e na le likarolo tsa eona tsa ho hanyetsa:
Li-Alloys tse thehiloeng ho Bronze: Kamehlasintered bronze(90% koporo, 10% tin) e hanyetsa ho apara hantle 'me e tšoarella nako e telele, e leng se etsang hore e be khetho e phahameng bakeng sa tšebeliso e ngata. Ho kenya graphite ho metsoako e entsoeng ka koporo ho li thusa hore li sebetse betere ka khohlano e fokolang le ho lula li tsitsitse lithempereichara tse ngata.
Lead BronzeLi-alloys tsena li na le lead ea 14-16% le thini e ka tlase ho 20% ho feta boronse e tloaelehileng ea 90-10. Li etsa hore likhohlano li fokotsehe 'me li hane ho lla hantle ha mafura a theoha. Liteko li paka hore lisebelisoa tsena li ka nka nako e telele ka makhetlo a 7-10 ho feta tšepe e phuthoang maemong a itseng (Pv=6-12 MPa·m/sec).
Metsoako ea Koporo-Tšepe: Meeli ena ea lebelo la li-alloys bakeng sa matla a ntlafetseng a khatello. Li sebetsa hantle bakeng sa ho tšoha le meroalo e boima. Ho eketsa 1.5% k'habone e sa lefelloeng ho etsa hore lisebelisoa tsena li phekoloe mocheso ho fihlela boima ba Rockwell C65, e leng se etsang hore li se ke tsa hlola li ama haholo.
Li-alloys tse thehiloeng ho tšepe: Tsena li theko e tlase empa li ntse li etsa li-bearings tse ntle, e leng se etsang hore li ratoe ke likoloi. Ba tšoara oli e ngata ka lebaka la porosity e phahameng 'me ba hana ho apara hantle, le hoja ba na le meeli e tlaase ea PV.
Mocheso oa sintering o phetha karolo e kholo ea ho apara thepa. Ultra High-Temperature Sintering (UHTS) e ka holimo ho 2500°F (1370°C) e etsa li-pores tse nyenyane, tse phatlalalitsoeng ho pholletsa le thepa. Sena se etsa hore likarolo li be matla, li be thata, 'me li se ke tsa roala ho feta mekhoa e tloaelehileng ea sintering.
Li-Self-Lubricating Sintered Bearings: Kamoo li Sebetsang Kateng
Li-bearings tsa sintered tse itšebetsang li sebetsa ka mokhoa o tsotehang o koetsoeng oa lubrication o sebetsang ntle le thuso ea kantle. Likarolo tsena li itlhokomela ka mekhoa e ikhethileng e lumellanang le maemo a ts'ebetso.
Mokhoa oa ts'ebetso ea Capillary
Matla a li-bearings tsa sintered tse itšebetsang a tsoa mohahong oa tsona o hokahaneng oa porous, o nang le 10% ho ea ho 35% ea palo eohle ea ho beleha. Li-pores tsena li theha marang-rang a rarahaneng ho pholletsa le thepa mme li sebetsa e le matamo a oli. Ho tlatsoa ha pele ha li-voids tsena ho etsahala ka "vacuum impregnation", moo moea o tlohang masobeng pele oli e kena. Mabota a masoba ebe a hula le ho tšoara oli ka matla a capillary - ts'ebetso e ts'oanang ea tlhaho e etsang hore mokelikeli o hloelle khahlanong le matla a khoheli libakeng tse thata.
Karolo ena ea capillary e theha seo baenjiniere ba se bitsang "running-in" bokaholimo ba lera le thellang. U tla bona ts'ebetso e tlase ea likhohlano le pele bering e fihla sebakeng sa eona se monate. The microstructure e sebetsa joaloka seponche se bolokang le ho ntša mafura ha ho hlokahala bophelong bohle ba sona.
Ho lokolloa ha oli nakong ea ts'ebetso
Bearing e ntša oli holim'a eona ka mekhoa e mengata ha e qala ho sebetsa. Mocheso o bakoang ke khohlano pakeng tsa shaft le bearing o etsa hore oli e atolohe. Katoloso ena e sutumelletsa oli e 'ngoe ka masobeng ho ea sebakeng se thellang.
Ho potoloha ha shaft ho etsa "ketso ea ho pompa" ka nako e le 'ngoe. Ketso ena e hlahisa libaka tse mpe tsa khatello filiming ea oli e tlotsang le ho hula oli e ngata ho tloha 'meleng o jereng ho ea holimo. Hammoho, phello ea ho pompa le ho atolosoa ha mocheso ho theha filimi e sireletsang ea oli pakeng tsa shaft le bere ho thibela ho kopana ha tšepe le tšepe.
Bearing e hloka ho sisinyeha ho potoloha ho sebetsa hantle. U hloka lebelo le phahameng le ho potoloha ho tsoelang pele ho boloka filimi e tletseng lubricating holim'a sebaka sa ho beha.
Ho tsosolosoa hape nakong ea Lipotoloho tsa ho Pholisa
Potoloho ea ho itšehla thajana e tsoela pele ha ho potoloha ho emisa 'me ho tsilatsila ho theoha. Oli e feteletseng e khutlela sebopeho sa porous ka liketso tsa capillary ha mocheso o theoha. Ho kenngoa hape hona ho thibela oli leha e le efe ho haha kapa ho rotha.
Bearing e hula oli e ileng ea qobelloa ho tsoa libakeng tse laetsoeng nakong ea ts'ebetso. Phapanyetsano ena e sa feleng - oli e tsoang nakong ea ts'ebetso le ho khutlela morao nakong ea phomolo - e theha potoloho e sa feleng ea lubrication. Ts'ebetso e boloka lubricant e hasana ka ho lekana sebakeng se thellang, kahoo ts'ebetso e lula e le matla le ha lera le thellang le ntse le putlama.
Metrics ea Ts'ebetso: Lintlha tsa PV le Meeli ea Mojaro
Baenjiniere ba sheba metrics e khethehileng ea ts'ebetso ho khetha li-bearings tse sintered tse lumellanang le litlhoko tse fapaneng tsa ts'ebetso. Litekanyetso tsena tsa tekheniki li thusa ho tseba meeli ea ts'ebetso e bolokehileng le ho thibela ho hloleha kapele.
Ho utloisisa Lintlha tsa PV ho Khetho ea ho Bearing
Ntlha ea PV e bapala karolo ea bohlokoa ho khethoeng li-bearings tse sintered. U e bala ka ho atisa mojaro oa ho beleha (P) ka liponto ka lisekoere tsa lisenthimithara tsa sebaka se lekanyelitsoeng sa ho beha ka lebelo la bokaholimo (V) maotong ka motsotso. Sena se re fa index ea mocheso o ferekaneng holim'a bokaholimo bo amang ka kotloloho hore na o nka nako e kae. Li-bearings tse tloaelehileng tsa porous hangata li na le boleng bo phahameng ba PV ba 50,000. Baetsi ba khothaletsa ho boloka ts'ebetso e tsoelang pele ho 20,000 ho lelefatsa bophelo ba ts'ebeletso ntle le lubrication e eketsehileng. Li-thrust bearings li hloka ho ts'oaroa ka hloko haholoanyane ka litekanyetso tse phahameng tsa PV tsa 10,000.
Nako ea bophelo ea Bearing e sebetsa ho fapana le boleng ba eona ba PV - PV e phahameng e bolela bophelo bo khuts'oane ba ts'ebeletso. Ke ka lebaka lena baenjiniere ba atisang ho khetha boleng bo tlase bo sireletsehileng ba PV nakong ea moralo ho etsa hore likarolo li tšoarelle nako e telele.
Static vs. Dynamic Load Capacity
Boemo bo sa sisinyeheng bo etsahala ha libaka tse nang le bokaholimo li sa sisinyehe. Matla a lintho tse bonahalang a fetoha ntho e ka sehloohong e fokotsang maemong ana. Moeli o tsitsitseng oa mojaro o bonts'a matla a fetolang bophara ba bering ka halofo ea mamello eohle e lumelletsoeng.
Moroalo o matla o kenyelletsa ho sisinyeha ho fokotsang ho beleha. Li-bearings tsa sintered hangata li na le litekanyetso tse matla tsa mojaro ho karolo ea boraro ea litekanyetso tsa tsona tse tsitsitseng. Phokotso ena e kholo e bontša kamoo ho sisinyeha ho tsoelang pele ho amang libaka tsa ho jara.
Meeli ea Lebelo la Lisebelisoa tse fapaneng tsa Sintered
Sebopeho se seng le se seng sa sintered se na le meeli ea lebelo la sona. Lisebelisoa tse thehiloeng ho boronse li u lumella ho matha ka lebelo le holimo. Liqapi tse thehiloeng ho tšepe li rekisa lebelo le itseng bakeng sa matla a ntlafetseng. Li-bearings tse tloaelehileng tsa sintered hangata li matha ka lebelo le holimo ho fihla ho maoto a 1000 ka motsotso.
Liphello tsa Mocheso Meeli ea Ts'ebetso
Mocheso o fetola haholo tsela eo li-bearings tse sintered li sebetsang ka eona. Bongata ba oli e tlotsang ka liminerale e sebetsa hantle lipakeng tsa 0-80°C. Ts'ebetso e theoha ka potlako ho feta 80 ° C, e theohela ho hoo e ka bang 60% ea litekanyetso tse tloaelehileng.
Mocheso o boetse o fetola tsela eo oli e tsamaeang ka eona ka har'a sebopeho sa porous. Lithempereichara tse futhumetseng li etsa hore oli e atolohe 'me e phalle habonolo ho tloha ho li-pores ho ea libakeng tse behang. Lithempereichara tse batang li etsa hore oli e be motenya, e leng se ka fokotsang ho tlotsa hantle ha o qala.
Ho bapisa Sintered Bearings vs Ball Bearings
Baenjiniere ba hloka ho utloisisa liphapang tsa mantlha lipakeng tsa sintered le li-ball bearings ho fihlela ts'ebetso e phahameng. Mefuta ena ea li-bearings e tla le melemo ea eona e etsang hore e be e loketseng tikolohong e itseng ea ts'ebetso.
Friction Coefficient Papiso
Li-ball bearings le sintered bearings li bonts'a litšobotsi tse fapaneng tsa likhohlano. Li-coefficients tsa likhohlano tsa libering tsa bolo li tlase, ho tloha ho 0.0008 ho isa ho 0.0035 ho latela mofuta. Li-bearings tse sintered li na le litekanyetso tse phahameng tsa likhohlano empa lia e etsa ka tsonasebopeho se kentsoeng ka oliseo se etsa hore li lule li tlotsoa. Khokahano ea likhohlano ka har'a li-sintered bearings e nyoloha ha oli e ntse e fokotseha, e leng se etsang hore e be khetho e mpe bakeng sa lits'ebetso tsa lebelo le holimo ntle le lubrication e nepahetseng.
Li-ball bearings ke bethe ea hau e ntle ka ho fetisisa ea ho fokotsa tahlehelo ea matla hobane e thella ho fapana le ho thella joalo ka li-bering tse sintered. Empa li-sintered bearings e ka ba khetho e ntle ho ts'ebetso ea ho emisa le ho ea. Litšobotsi tsa tsona tsa ho itlholisa li thibela litaba tsa ho thella ha lithupa tseo hangata u li bonang ho li-ball bearing tse sa tlotsoang hantle.
Litšobotsi tsa Lerata le Vibration
Li-bearings tse sintered li matha ho khutsitse ho feta li-ball bearings, haholo-holo ka lebelo le phahameng. Li-ball bearings li baka lerata hobane lintho tsa tsona tse bilikang lia kopana. Maemo a lerata a atisa ho eketseha ha li-ball bearings li fihla qetellong ea bophelo ba tsona.
Li-ball bearings li romela ho thothomela haholoanyane ka litsamaiso tsa mochini. Lipatlisiso li bontša hore ho thothomela ho hoholo ho ka khutsufatsa bophelo le ho etsa lerata le ho feta. Ho thella ho li-bearings tse sintered ho li thusa ho monya ho thothomela hantle. Sena se ba etsa khetho e ntle bakeng sa lits'ebetso moo lerata le hlokang ho beoa fatše.
Litlhoko tsa Tlhokomelo: E hlophisitsoeng vs. Ho Itlhokomela
Litlhoko tsa tlhokomelo ea li-bearings tsena li fapane haholo. Li-ball bearings li hloka ho tlotsoa khafetsa ho lula li matha hantle le ho qoba ho hloleha kapele. Li-bearings tse sirelelitsoeng li boloka oli ka har'a sebopeho sa tsona sa porous, e leng se etsang hore ho be le mokhoa oa ho itlotsa o hlokang tlhokomelo e fokolang.
U hloka litsebi tse nang le litsebo ho hlahloba li-ball bears ka nako ea litšebeletso. Li-bering tse sintered li ntse li sebetsa le ha li qala ho hloleha. Hangata li etsa lerata ho e-na le hore li phahamise ka ho feletseng—ho fapana le li-bearings tse ka ’nang tsa notlela ntle ho temoso.
Nako ea Bophelo Tlas'a Maemo a fapaneng a Ts'ebetso
Li-ball bearings li tšoarella nako e telele maemong a lebelo le phahameng. Tikoloho ea ho sebetsa e na le karolo e kholo ea hore na mofuta o mong le o mong o sebetsa hantle hakae. Li-bearings tse sintered li sebetsa hantle ts'ebetsong e tsitsitseng, e itekanetseng. Li-ball bearings li sebetsana hantle le ho emisa ho qala le ho khutlisetsa morao.
Mocheso o ama hore na mefuta e 'meli e behang e nka nako e kae. Li-ball bearings li sebetsa hantle ho pholletsa le mefuta e mengata e fapaneng ea mocheso, e phahameng le e tlase. Li-bearings tse sintered li sebetsa hantle ho fihla ho 85°C. Ka holim'a moo, ba lahleheloa ke bokhoni ba bona ba ho tlotsa ka potlako.
Qetello
Li-Sintered bearings li emela katleho ea boenjiniere e kopanyang metallurgy ea phofo le bokhoni ba ho itlotsa. Sebopeho sa bona sa porous se etsa 10% ho 35% ea kakaretso ea molumo 'me se etsa marang-rang a likanale tse hokahaneng tse tiisang hore lubrication e tsoela pele.
Li-bearings tsena tse ncha li lula li tsitsitse ka mokhoa o fapaneng mochesong o fapaneng 'me li boloka matla ka ho lekana ho pholletsa le sebopeho sa tsona. Leha likhokahano tsa tsona tsa likhohlano li feta tsa li-ball bearing, tlhaho ea tsona ea ho itlotsa e li etsa hore li phethahale bakeng sa lits'ebetso tse hlokang tlhokomelo e fokolang le ts'ebetso e tsitsitseng.
Ts'ebetso ea tlhahiso e itšetlehile ka ho nepahala ha metallurgical le mocheso o khethehileng oa sintering pakeng tsa 800 ° C le 850 ° C. Sena se theha li-bearings tse sebetsang ka ts'epo ho lintlha tsa PV ho fihla ho 50,000. Mefuta e tloaelehileng ea boronse e nang le 90% ea koporo le 10% tin e fana ka tšireletso e babatsehang khahlanong le ho senya le ho senya. Thepa ena e etsa hore e be ea bohlokoa maemong a phahameng a tlhahiso.
Baenjiniere ba fumana melemo ea sintered bearings e le ea bohlokoa. Li sebetsa ka khutso, ha li hloke tlhokomelo e fokolang, 'me li sebetsa ka mokhoa o tšepahalang tlas'a lebelo le mejaro e itekanetseng. Ha li kopantsoe le ho itšehla thajana, likarolo tsena li li etsa khetho e ntle ka ho fetisisa ha ts'ebetso e tsitsitseng, e sa hlokeng tlhokomelo e bohlokoa ho feta lebelo le phahameng kapa boima ba mojaro.