Ukukhethwa Kokuthwala Kwemishini: Izindlela Eziyinhloko Nokucatshangelwa Kokufaneleka

Isingeniso

Ukukhetha i-bearing akuyona nje into yokuzijwayeza ikhathalogi; kuyisinqumo sokuklama esithinta umthamo womthwalo, isivinini, ukuqina, ukungqubuzana, impilo yesevisi, kanye nengozi yokugcinwa kuwo wonke umshini. Ukukhetha okulungile kuncike ekutheni imithwalo ye-radial ne-axial isebenzisana kanjani nesivinini sokusebenza, ukuthambisa, izinga lokushisa, ukungcola, kanye nezimo zokufaka, kufaka phakathi ukulingana phakathi kwe-bearing, i-shaft, kanye nendlu. Lesi sihloko sichaza izindlela eziyinhloko ezisetshenziswa ukuqhathanisa izinhlobo ze-bearing futhi sichaza ukuthi ukukhetha ukulingana kuthinta kanjani ukusebenza, ukususwa kwangaphakathi, kanye nengozi yokwehluleka. Ekugcineni, abafundi bazoba nohlaka olusebenzayo lokufanisa izici ze-bearing nezimo zokusebenza zangempela nokugwema amaphutha avamile okucacisa.

Kungani Ukukhetha Okubalulekile

Ukucacisa i-bearing efanele kuyisifundo sobunjiniyela esiyisisekelo esinquma ngqo ubuqotho bemishini, ukusebenza kahle, kanye nobude besikhathi semishini ejikelezayo. Ngenkathi ama-bearing engase abonakale njengezingxenye ezithengiswa kakhulu, i-physics yobunjiniyela elawula ukusebenza kwawo iyinkimbinkimbi kakhulu, ehilela i-non-linear contact mechanics, i-elastohydrodynamic lubrication, kanye nesayensi yezinto ezibonakalayo enembile. Ukukhetha i-bearing efanele kudinga ukuhlaziywa okujulile kwezimo zemingcele ethile yesicelo kunokuthembela kusibonelo somlando noma ukulinganisa kwekhathalogi.

Lapho onjiniyela belaphaincazelo yokuthwalaNjengokucatshangelwa kamuva, izinhlelo zemishini ezivelayo zivame ukuhlushwa yizilinganiso zokusebenza ezingezinhle kakhulu, ukudlidliza ngokweqile, kanye nokwehluleka okukhulu kwangaphambi kwesikhathi. Indlela ehlelekile yokukhetha amabhere inciphisa lezi zingozi, iqinisekisa ukuthi ingxenye ekhethiwe iyavumelana nomgodi, indlu, kanye nezimo zemvelo zangaphandle.

Umthelela womjikelezo wokuphila ekuthembekeni kanye nezindleko

Imiphumela yezezimali kanye nokusebenza kokukhethwa kwamabhere idlula kakhulu izindleko zokuthenga zokuqala. Ezisetshenzisweni zezimboni, izindleko eziphelele zobunikazi (i-TCO) zigxile kakhulu ezinkathini zokulungisa kanye nesikhathi sokungasebenzi esingahleliwe. Isibonelo, ibhere elibiza u-$500 lingadala kalula imali engenayo yokukhiqiza elahlekile engu-$50,000 uma lehluleka ngaphambi kwesikhathi empahleni ebalulekile. Onjiniyela bavame ukuklama impilo ethile yesilinganiso esiyisisekelo se-L10—ngokuvamile bahlose amahora ayi-100,000 amabhokisi egiya ezimboni asebenza njalo noma imishini yokukhiqiza ugesi.

Ukufeza lo mjikelezo wokuphila okuqondiwe kudinga ukuhambisana okunembile phakathi komthamo womthwalo oguquguqukayo webhereyi kanye nemithwalo yangempela yokusetshenziswa. Ubunjiniyela obudlulele ngokukhetha ibhereyi enesilinganiso somthwalo esiphezulu kakhulu kungaba yingozi njengokungabi nosayizi ophansi; amabhereyi amakhulu kakhulu asebenza ngaphansi kwezimo zomthwalo omncane (ngokuvamile adinga okungenani u-2% wesilinganiso somthwalo oguquguqukayo) asengozini yokuguguleka kwe-roller kanye nokuguguleka kwe-adhesive, okunciphisa kakhulu ukuthembeka.

Izingozi zokusebenza zokucaciswa okungekuhle

Ukwehluleka ukuchaza ngokunembile amapharamitha okusebenza ngesikhathi sesigaba sokucaciswa kuletha izingozi ezinkulu zokusebenza. Idatha yemboni ikhombisa ukuthi yize cishe ama-34% okwehluleka kwama-bearing ngaphambi kwesikhathi kuvela ezinkingeni zokuthambisa, ama-16% abalulekile abangelwa ngqo ukukhethwa okungekuhle kokuqala kanye nokulingana okungafanele. Lapho i-bearing ibhekene nemithwalo, isivinini, noma amazinga okushisa ngaphandle kwesakhiwo sayo, ukucindezeleka okubangelwayo kuvela ngokushesha.

Izindlela ezivamile zokwehluleka ezivela emaphutheni okucacisa zifaka phakathi ukuhlanza okungokoqobo okuvela ekugcwaleni ngokweqile okungaguquki, ukuchelela okuncane ngenxa yokungafaneleki kobukhulu befilimu ye-elastohydrodynamic, kanye nokuqhekeka kwekheji okuvela emandleni amakhulu e-centrifugal ngesivinini esikhulu. Lezi zindlela zokwehluleka azigcini nje ngokubhubhisa ibhereyitha kodwa zivame ukubangela umonakalo obalulekile kuma-shaft, ama-housings, kanye nama-gearing aseduze, okudinga ukulungiswa okukhulu nokubizayo kwemishini.

Izindlela Zobuchwepheshe Zokukhetha Amabhere

Ukuhumusha izidingo zomshini zibe yi-geometry ethile yokuthwala kudinga ukuhlola i-matrix yezindlela zobuchwepheshe ezisebenzisanayo. Akukho pharamitha eyodwa engahlukaniswa; amakhono esivinini athonya ukukhetha kokugcoba, kuyilapho ubukhulu bomthwalo bunquma ukuvuleka kwangaphakathi okudingekayo ukuvimbela ukulayisha kusengaphambili okubi ngesikhathi sokusebenza.

Umthwalo, isivinini, ukuqina, kanye nokungahambisani kahle

Izinto eziyisisekelo ezibangela ukwakheka kwamabhereyitha yimithwalo esetshenzisiwe (i-radial, i-axial, noma ehlanganisiwe) kanye nesivinini sokujikeleza. Isilinganiso somthwalo oguquguqukayo (C) kanye nesilinganiso somthwalo omile (C0) kumele kuhlolwe ngokumelene nomthwalo olinganayo wamabhereyitha oguquguqukayo (P). Kuzinhlelo zokusebenza zesivinini esikhulu, onjiniyela basebenzisa i-speed factor (ndm), ebalwa njengobubanzi bephimbo ngamamilimitha aphindaphindwe ngesivinini ku-RPM. Ama-spindle amathuluzi omshini avame ukudinga amanani e-ndm adlula i-1,000,000, okudinga ukuthintana okuqondile kwe-angular.amabhereyi ebholangezinto ezigoqekayo ze-ceramic.

Izidingo zokuqina zilawula i-geometry yangaphakathi kanye nama-engeli okuxhumana, ikakhulukazi ekusetshenzisweni kwamathuluzi okunembile lapho ukuphambuka komgodi kufanele kuncishiswe khona. Ngaphezu kwalokho, ukungalingani kwesakhiwo kumele kubalwe. Ngenkathi ama-deep groove ball bearing ngokuvamile angamukela ngaphansi kwama-degrees angu-0.15 okungalingani, izinhlelo zokusebenza ezinokugoba okukhulu komgodi zingadingaamabheringi e-roller ayindilingas](https://www.demy-bearings.com) ekwazi ukukhokhela ukungalingani okuguquguqukayo okufika kuma-degree angu-2.0.

Ukulingana, imvume yangaphakathi, kanye nokubekezelelana

Ukubekezelelana kobukhulu kanye nokulingana kulawula indlela ibhereyitha esebenzisana ngayo nezingxenye zayo zokuhlangana. Amabhereyitha akhiqizwa ngokwezigaba ezithile zokubekezelelana kwe-ISO (isb., Okujwayelekile, P6, P5, P4), kanye nezigaba zokunemba okuphezulu ezidingekayo kwizinhlelo zokusebenza ezidinga ukulawulwa okuqinile kokugijima. Ukukhethwa kokulingana kweshafti kanye nendlu—kungakhathaliseki ukuthi ukuphazamiseka (ukucindezela) noma ukususwa (ukushelela)—kuncike ohlotsheni lomthwalo (indandatho ejikelezayo vs. engashintshi).

Okubaluleke kakhulu, ukulingana kokuphazamiseka kwandisa indandatho yangaphakathi futhi kucindezele indandatho yangaphandle, kunciphisa i-radial internal clearance yebheyira (RIC). Uma kudingeka ukulingana kokuphazamiseka okukhulu, onjiniyela kumele bacacise i-beyira ene-initial internal clearance enkulu, njenge-C3 noma i-C4. Isibonelo, ukulingana kokuphazamiseka okujwayelekile kunganciphisa i-internal clearance ngo-0.015 mm kuya ku-0.030 mm; ukwehluleka ukukuqaphela lokhu kungabangela i-internal clearance engemihle, okuholela ekubalekeni okusheshayo kokushisa kanye nokubanjwa.

Ukugcotshwa, ukuvalwa, izinga lokushisa, kanye nokungcola

Indawo yokusebenza inquma izidingo ze-tribological kanye nezinto ezibonakalayo. Insimbi yokuthwala ejwayelekile (njenge-52100 noma i-100Cr6) idlula ekungazinzini kobukhulu emazingeni okushisa aphezulu futhi ivame ukukhawulelwa emazingeni okushisa okusebenza angaphansi kuka-120°C. Uma ukusebenza okuqhubekayo kudlula u-150°C, amasongo okuthwala kumele adlule ezinqubweni ezikhethekile zokushisa (isb., ukuzinza kwe-S1 noma i-S2) ukuvimbela ukuguqulwa kwensimbi kanye nokwanda kwevolumu.

Ukukhetha ukugcotshwa—amafutha uma kuqhathaniswa namafutha—kuqhutshwa yisivinini sokusebenza kanye nezidingo zokushabalalisa ukushisa. I-grease iyathandwa ngenxa yezakhiwo zayo zokuvala kanye nokugcinwa okuphansi kodwa ngokuvamile inqunyelwe kumanani aphansi e-ndm. Ezindaweni ezingcoliswe kakhulu, njengezimayini noma imishini yezolimo, izixazululo zokuvala eziqinile (njengezimbobo ze-elastomer zezindebe ezintathu noma izimbobo ze-labyrinth) ziyimpoqo ukuvimbela ukungena kwezinhlayiya, okonakalisa ngokushesha i-grease futhi kuqalise ukuguguleka komzimba okuthathu.

Ukuqhathanisa Izinhlobo Zokuthwala

Umehluko wesimo phakathi kwezinto ezigoqekayo—ikakhulukazi noma ngabe zisebenzisa ukuthintana kwephuzu noma ukuthintana komugqa—ngokuyisisekelo ushintsha izici zokusebenza kwebhereyi. Ukuzulazula kukhathalogi ehlukahlukene yezinhlobo zebhereyi kudinga ukuqonda ukuthi i-geometry yangaphakathi isabela kanjani emandleni okusetshenziswa kwe-macroscopic.

Umehluko obalulekile phakathi kwezinhlobo ezinkulu zokuthwala

Umehluko omkhulu phakathi kwezinhlobo zamabhere ulele ekusabalalisweni kwawo kokuthwala imithwalo kanye nokuziphatha kwe-kinematic. Amabhere ebhola elijulile aguquguqukayo kakhulu, anikeza amakhono esivinini angavamile kanye nokungqubuzana okuphansi, kodwa anqunyelwe ekusetshenzisweni kwemithwalo esindayo. Ngokuphambene nalokho, amabhere e-cylindrical roller avelele ekusekeleni imithwalo emikhulu ye-radial ngenxa yendawo yawo yokuxhumana ende kodwa anikeza umthamo womthwalo we-axial ongelutho ngaphandle kokuthi ubekwe ngqo.

Ukuqonda lezi mikhawulo ezingokwemvelo kuvumela onjiniyela ukuthi bahlanganise izinhlobo zamabhereyi ngendlela efanele. Ilungiselelo elivamile lisebenzisa ibhereyi engaguquki (isb., ibhereyi yokuxhumana enemigqa emibili) ukuthola i-shaft ngokwe-axial, ehambisana nebhereyi entantayo (isb., ibhereyi ye-roller eyindilinga) ukuze ivumelane nokwanda kokushisa kwe-shaft ngaphandle kokubangela imithwalo yokusunduza ebangelwa yizinambuzane.

Isikhathi sokusebenzisa ama-ball vs roller bearings

Isinqumo phakathi kwama-ball nama-roller bearings sincike kakhulu ngobukhulu bomthwalo osetshenzisiwe kanye nokucindezeleka kokuxhumana kwe-Hertzian okubangelwa yilokhu. Ngenxa yokuthi ama-ball bearings asebenzisa ukuxhumana kwephuzu, ukuhlushwa kokucindezeleka emgwaqweni womjaho kuphakeme kakhulu ngaphansi kwemithwalo elinganayo uma kuqhathaniswa nokuxhumana komugqa kwe-roller bearings. Njenge-heuristic ejwayelekile, i-roller bearings inikeza cishe amandla omthwalo we-radial aphindwe kathathu kuya kahlanu kunomthamo we-ball bearings olingana.

Kodwa-ke, lokhu kukhula komthamo womthwalo kuza ngezindleko ze-kinematic. Ukuxhumana komugqa kuma-roller bearings kudala ukungqubuzana okuphezulu futhi kusengozini enkulu yokulayisha umphetho uma kwenzeka ukungalungi kahle. Ngenxa yalokho, ama-roller bearings ngokuvamile ancishiswa ngo-20% kuya ku-30% ngesivinini esiphezulu esivunyelwe uma kuqhathaniswa nama-ball bearings anobubanzi obufanayo be-bore. Ngakho-ke, ama-ball bearings ayisinqumo esizenzakalelayo sama-electrical motors anejubane eliphezulu kanye nama-spindles aqondile, kuyilapho ama-roller bearings ebusa ama-gearbox asindayo, ama-rolling mills, kanye nama-wind turbine main shafts.

Inqubo Yokukhetha Amabhere

Ukushintsha kusuka ezidingweni zemfundiso kuya kubhili yezinto eziqediwe kudinga umsebenzi ohlelekile kakhulu nophindaphindayo. Inqubo yokukhetha amabhereyi ayivamile ukuba yiqondile; ukuthola imingcele yokushisa esinyathelweni sesine kuvame ukudinga ukubuyela esinyathelweni sesibili ukuze ukhethe ukwakheka kwamabhereyi okuhlukile noma isu lokuthambisa.

Uhlelo lokusebenza lokukhetha isinyathelo ngesinyathelo

Umsebenzi wokukhetha ojwayelekile uqala ngokubhala phansi ngokuphelele izimo zomngcele wohlelo lokusebenza: imithwalo emincane nemikhulu, amaphrofayili esivinini, imijikelezo yomsebenzi, kanye namazinga okushisa azungezile. Ngokusekelwe kulokhu okufakwayo, onjiniyela bakhetha uhlobo olujwayelekile lokuthwala (isb., i-roller ethambile vs. ibhola elijulile lomgodi) oluhambisana nesiqondiso somthwalo kanye nobukhulu.

Uma uhlobo selukhethiwe, usayizi othize unqunywa ngokubala isilinganiso somthwalo oguqukayo esidingekayo ukuze kuhlangatshezwane nokuphila okuqondiwe kwe-L10. Ngemva kokunqunywa kosayizi, umsebenzi ushintshela ekuchazeni indawo ezungezile: ukubala ukubekezelelana okuhle komgodi kanye nezindlu, ukukhetha isigaba sokuhlanza sangaphakathi esifanele, nokucacisa uhlobo lokugcoba kanye nendlela yokulethwa. Isinyathelo sokugcina sihilela ukuqinisekisa ukuthi usayizi wokuthwala okhethiwe kanye nokugcoba kungasusa ngokuphephile ukushisa kokungqubuzana okukhiqizwe emazingeni okushisa okusebenza azinzile.

Ukuqinisekiswa ngokubala nokuhlola

Ukukhethwa kwethiyori kumele kuqinisekiswe ngokuqinile kusetshenziswa amamodeli wokubala athuthukile kanye nokuhlolwa okubonakalayo. Ubunjiniyela besimanje buthembele ku-modified rating life equation (ISO 281), enwebeka ekubalweni okuyisisekelo kwe-L10 ngokwethula i-life modification factor ($a_{ISO}$). Lesi sici sibheka isimo sokugcoba nge-kinematic viscosity ratio ($\kappa$) kanye ne-contamination factor ($e_c$). Ukuze uthole ifilimu yokugcoba ye-elastohydrodynamic efanele, kuhloswe inani le-$\kappa$ eliphakathi kuka-1.0 no-4.0.

Ngaphandle kokubala kokuhlaziya, izinhlelo zokusebenza ezibalulekile zidinga ukuhlaziywa kwezinto ezilinganiselwe (i-FEA) ukuqinisekisa ukuthi ukuphambuka kwezindlu ngaphansi kwemithwalo ephezulu akuphambuki indandatho yangaphandle yokuthwala, okungaholela ekugxilweni okukhulu komthwalo. Okokugcina, ukuqinisekiswa ngokomzimba ngokuhlolwa kwebhentshi okusheshayo—ngokuvamile okudinga amahora angu-500 kuya ku-1,000 okusebenza okuqhubekayo ngaphansi kwemijikelezo yomsebenzi olingiswayo—kwenziwa ukuqinisekisa ukuzinza kokushisa, ukugcinwa kwamafutha, kanye namaphrofayili okukhishwa kwe-acoustic ngaphambi kokugunyazwa kokukhiqiza okugcwele.

Ukuthuthukisa Ukusebenza Nokutholakala

Ukwakha ikhambi elihle kakhulu lokuthwala amabherethi kuyingxenye yenselele kuphela; ingxenye echaziwe kumele futhi ibeokusebenziseka kalula kwezentengiselwano, okukhiqizwayo, futhi okulungisekayo phakathi nesikhathi sokuphila kwemishini. Ukuthola ibhalansi efanele phakathi kokuphelela kobuchwepheshe obuphelele kanye nokusebenza kahle kochungechunge lokuhlinzeka kuyisibopho esibalulekile sonjiniyela wokuklama.

Ukucatshangelwa kokuma kanye nokuhlinzekwa

Imakethe yokuthwala impahla emhlabeni wonke ihlelwe kahle kakhulu ngokuphathelene ne-ISO metric kanye nobukhulu bomngcele we-ABMA intshi. Ukucacisa ikhathalogi ejwayelekile yokuthwala impahla kusukela ochungechungeni olufana no-6200, 6300, noma u-22200 kuqinisekisa ukutholakala kwemithombo eminingi, amanani okuncintisana, kanye nokutholakala kokufakwa esikhundleni ngokushesha kwabasebenzisi bokugcina. Ukuphambuka kulezi zindinganiso kuletha ukungqubuzana okukhulu kweketanga lokuphakelwa.

Uma onjiniyela becacisa amajiyometri angaphakathi ngokwezifiso, ukuvalwa kobunikazi, noma ubukhulu obungejwayelekile, kumele babhekane nezijeziso ezinzima zezokuthutha. Ama-bearings ngokwezifiso avame ukunquma Ubuningi Boku-oda Obuncane (ama-MOQ) obudlula amayunithi ayi-1,000 futhi ahilela izikhathi zokuhola zokukhiqiza ezisukela emavikini angama-24 kuya kwangama-40. Ngaphandle kokuthi uhlelo lokusebenza lukhethekile kakhulu—njengokusebenza kwezindiza noma amarobhothi aqinile kakhulu—izindleko eziphelele zobunikazi zisiza kakhulu ukuklama izindlu ezizungezile kanye neshaft ukuze kufakwe i-bearings ejwayelekile ye-Commercial Off-The-Shelf (COTS).

Isiqondiso sesinqumo sokugcina

Isinqumo sokugcina sokucaciswa kufanele sihlolwe nge-matrix elinganisa ukusebenza kobuchwepheshe ngokutholakala kwezentengiselwano. Onjiniyela kufanele bagunyaze ukubuyekezwa komklamo okuphonsela inselelo isidingo sezigaba zokubekezelelana okunembe kakhulu (njenge-ABEC 7/ISO P4) noma izinto ezingavamile uma uhlelo lokusebenza lungazidingi ngokuqinile, njengoba lezi zici zandisa izindleko zamayunithi ngokushesha.

Ekugcineni, ukukhethwa okuphumelelayo kwamabhereyi kufinyelela emdwebweni wobunjiniyela ophelele ochaza ngokusobala hhayi nje inombolo yengxenye, kodwa nemingcele yokuvula edingekayo, isigaba sokubekezelelana, izinto zekheji, kanye nemingcele yokugcoba. Ngokunamathela ngokuqinile enkambisweni yokukhetha eqinisekisiwe ngokwezibalo futhi enolwazi lwezentengiselwano, onjiniyela baqinisekisa ukutholakala okuphezulu kwempahla futhi bavikele ukuthembeka kwemishini komkhiqizo wokugcina.

Izinto Ezibalulekile Okufanele Uzicabangele

• Iziphetho ezibaluleke kakhulu kanye nesizathu sokukhetha ukuthwala
• Imininingwane, ukuhambisana, kanye nokuhlolwa kwengozi okufanele kuqinisekiswe ngaphambi kokuthi uzibophezele
• Izinyathelo ezilandelayo ezisebenzayo kanye nezixwayiso abafundi abangazisebenzisa ngokushesha

imibuzo ejwayelekile ukubuzwa

Ngilukhetha kanjani uhlobo olufanele lokuthwala umshini wami?

Qondanisa umthwalo nesivinini kuqala: umsele ojulile wemithwalo ejwayelekile ye-radial, ukuthintana kwe-angular kwemithwalo ehlanganisiwe, i-roller ethambile noma eyindilinga yemithwalo esindayo, kanye nama-needle bearings lapho isikhala silinganiselwe khona.

Kunini lapho kufanele ngisebenzise khona i-interference fit esikhundleni se-clearance fit?

Sebenzisa ukulingana kokuphazamiseka endandatho engaphansi komthwalo ojikelezayo ukuze uvimbele ukukhukhuleka. Sebenzisa indawo evulekile noma eshelelayo endandatho engaphansi komthwalo ongashintshi ukuze kube lula ukufaka nokunciphisa ukucindezeleka okubangelwa ukulingana.

Kungani ukuhlukaniswa kwangaphakathi kubalulekile ekukhetheni amabhere?

Ukulingana kanye nokushisa kokusebenza kunganciphisa ukususwa kwangaphakathi kwe-radial. Khetha isigaba sokususwa ukuze i-bearing ingalayishi kusenesikhathi, ikakhulukazi emishinini enesivinini esikhulu, esindayo, noma esebenza ngokushisa.

Yiziphi izinketho zokuthwala ezinikezwa yi-DEMY zezinhlelo zokusebenza ze-OEM nezezimboni?

I-DEMY inikeza ama-ball nama-roller bearings afaka phakathi i-deep groove, i-angular contact, i-tapered, i-cylindrical, i-spherical, i-needle, i-thrust, i-stainless, i-ceramic, kanye nezinhlobo zokuzigcoba ezisetshenziswa imishini eminingi.

Ngingaqinisekisa kanjani ukuthi i-bearing ilungile kusuka kukhathalogi ye-e-DEMY?

Hlola imbobo, ububanzi bangaphandle, ububanzi, uhlobo lomthwalo, isivinini, izidingo zokulingana, kanye nendawo yokusebenza. Bese uqinisekisa isigaba sokunemba, ukususwa, kanye nezinto ezikukhathalogi ye-e noma ucele ukwesekwa kobuchwepheshe ukuze kuqinisekiswe okokugcina.