Mapampu ndi amodzi mwa omwe amagwiritsa ntchito kwambiri zisindikizo zamakina. Monga momwe dzinalo likusonyezera, zisindikizo zamakina ndi zisindikizo zamtundu wa kukhudzana, zosiyana ndi zisindikizo za aerodynamic kapena labyrinth zosakhudzana.Zisindikizo zamakinaamadziwikanso ngati chisindikizo chamakina cholinganizidwa kapenachisindikizo chamakina chosalinganikaIzi zikutanthauza kuchuluka kwa mphamvu ya ndondomeko, ngati ilipo, komwe kungabwere kumbuyo kwa nkhope yosindikizira yosasuntha. Ngati nkhope yosindikizira siikankhidwira ku nkhope yozungulira (monga momwe zimakhalira ndi chisindikizo cha mtundu wa pusher) kapena madzi a ndondomeko pa mphamvu yomwe ikufunika kutsekedwa saloledwa kufika kumbuyo kwa nkhope yosindikizira, mphamvu ya ndondomekoyo ingapukute nkhope yosindikizira kumbuyo ndikutseguka. Wopanga chisindikizo ayenera kuganizira momwe zinthu zimagwirira ntchito kuti apange chisindikizo ndi mphamvu yotseka yofunikira koma osati mphamvu yochuluka kwambiri kotero kuti katundu wonyamula pa nkhope yosindikizira yosinthasintha imapanga kutentha kwambiri ndi kuwonongeka. Iyi ndi njira yosalala yomwe imapangitsa kapena kusokoneza kudalirika kwa pampu.
Chisindikizo champhamvu chimayang'ana mwa kulola mphamvu yotsegulira m'malo mwa njira yachizolowezi yochitira
Kulinganiza mphamvu yotsekera, monga tafotokozera pamwambapa. Sikuchotsa mphamvu yotsekera yofunikira koma kumapatsa wopanga pampu ndi wogwiritsa ntchito chogwirira china choti atembenuze mwa kulola kuchotsa kapena kutsitsa nkhope zotsekera, pamene akusunga mphamvu yotsekera yofunikira, motero kuchepetsa kutentha ndi kuwonongeka pamene akukulitsa mikhalidwe yogwirira ntchito.
Zisindikizo Zouma za Gasi (DGS), yomwe nthawi zambiri imagwiritsidwa ntchito mu ma compressor, imapereka mphamvu yotsegulira pamwamba pa chisindikizo. Mphamvu iyi imapangidwa ndi mfundo yoyendetsera mpweya, pomwe mizere yopapatiza bwino imathandizira kulimbikitsa mpweya kuchokera kumbali ya kupanikizika kwamphamvu kwa chisindikizo, kulowa m'malo otseguka komanso pamwamba pa chisindikizo ngati chonyamulira chamadzimadzi chosakhudzana ndi kukhudzana.
Mphamvu yotsegulira mpweya wouma pa malo osungira mpweya. Kutsetsereka kwa mzerewu kukuyimira kuuma kwa malo osungira mpweya. Dziwani kuti malo osungira mpweyawo ali mu ma microns.
Chomwecho chimachitika mu ma bearing amafuta a hydrodynamic omwe amathandizira ma compressor akuluakulu ambiri a centrifugal ndi ma pump rotor ndipo chimawonekera mu rotor dynamic eccentricity plots omwe akuwonetsedwa ndi Bently. Izi zimapangitsa kuti kumbuyo kukhale kokhazikika ndipo ndi chinthu chofunikira kwambiri pakuchita bwino kwa ma bearing amafuta a hydrodynamic ndi DGS. Zisindikizo zamakanika zilibe ma grooves abwino opompa omwe angapezeke pankhope ya DGS ya aerodynamic. Pakhoza kukhala njira yogwiritsira ntchito mfundo zoyendetsera mpweya wopanikizika kunja kuti muchepetse mphamvu yotseka kuchokera kunkhope yosindikizira yamakinas.
Ma grafu abwino a magawo oyendetsera filimu yamadzimadzi poyerekeza ndi chiŵerengero cha eccentricity cha journal. Kuuma, K, ndi damping, D, ndizochepa kwambiri pamene journal ili pakati pa bearing. Pamene journal ikuyandikira pamwamba pa bearing, kuuma ndi damping kumawonjezeka kwambiri.
Ma bearing a mpweya wopanikizika akunja amagwiritsa ntchito gwero la mpweya wopanikizika, pomwe ma bearing amphamvu amagwiritsa ntchito mayendedwe pakati pa malo kuti apange kupanikizika kwa mpata. Ukadaulo wopanikizika wakunja uli ndi ubwino wofunikira ziwiri. Choyamba, mpweya wopanikizika ukhoza kulowetsedwa mwachindunji pakati pa nkhope za seal mwanjira yolamulidwa m'malo molimbikitsa mpweya kulowa mu mpata wa seal ndi mipata yosaya yomwe imafuna kuyenda. Izi zimathandiza kulekanitsa nkhope za seal musanayambe kuzungulira. Ngakhale nkhope zitakulungidwa pamodzi, zidzatseguka kuti zisakhale ndi kukangana ndipo zimayima pamene kupanikizika kwalowetsedwa mwachindunji pakati pawo. Kuphatikiza apo, ngati seal ikutentha, ndizotheka ndi kupanikizika kwakunja kuwonjezera kukakamiza kumaso kwa seal. Mpatawo ungawonjezereke mofanana ndi kupanikizika, koma kutentha kuchokera ku shear kumagwera pa ntchito ya cube ya mpata. Izi zimapatsa wogwiritsa ntchito mphamvu yatsopano yogwiritsira ntchito motsutsana ndi kupanga kutentha.
Pali ubwino wina mu ma compressor chifukwa palibe kuyenda kwa mpweya pamwamba pa nkhope monga momwe zilili mu DGS. M'malo mwake, kuthamanga kwakukulu kumakhala pakati pa nkhope za seal, ndipo kuthamanga kwa mpweya wakunja kudzalowa mumlengalenga kapena kutuluka mbali imodzi ndi kulowa mu compressor kuchokera mbali inayo. Izi zimawonjezera kudalirika poteteza njirayo kuti isalowe m'malo olakwika. Mu ma pump izi sizingakhale zabwino chifukwa zingakhale zosafunikira kukakamiza mpweya wopanikizika kulowa mu pamp. Mpweya wopanikizika mkati mwa ma pump ukhoza kuyambitsa mavuto a cavitation kapena air hammer. Komabe, zingakhale zosangalatsa kukhala ndi seal yosakhudzana kapena yopanda kukangana ya ma pump popanda vuto la kuyenda kwa mpweya kulowa mu pamp. Kodi zingatheke kukhala ndi mpweya wopanikizika wakunja wopanda kuyenda konse?
Malipiro
Ma bearing onse opanikizika akunja ali ndi mtundu wina wa malipiro. Malipiro ndi mtundu wa malire omwe amaletsa kupanikizika. Njira yodziwika kwambiri yolipirira ndi kugwiritsa ntchito ma orifices, koma palinso njira zolipirira ma groove, step and porous. Malipiro amalola ma bearing kapena ma seal faces kuti aziyenda pafupi popanda kukhudza, chifukwa akayandikira, mpweya wapakati pawo umakwera, zomwe zimapangitsa kuti nkhopezo zigawanike.
Mwachitsanzo, pansi pa mpweya wozungulira wopindika (Chithunzi 3), avareji
Kupanikizika mu mpata kudzafanana ndi katundu wonse pa bearing wogawidwa ndi malo a nkhope, uku ndi kukweza kwa unit. Ngati kuthamanga kwa mpweya wa gwero ili ndi mapaundi 60 pa inchi imodzi (psi) ndipo nkhope ili ndi inchi imodzi ya inchi imodzi ndipo pali mapaundi 300 a katundu, padzakhala avareji ya 30 psi mu mpata woperekera. Nthawi zambiri, mpata umakhala pafupifupi mainchesi 0.0003, ndipo chifukwa chakuti mpatawo ndi wochepa kwambiri, kuyenda kwake kumakhala pafupifupi 0.2 standard cubic feet pamphindi (scfm). Chifukwa pali choletsa cholowera m'mphepete mwa msewu chisanafike mpata womwe ukuletsa kupanikizika kumbuyo, ngati katunduyo akwera kufika pa mapaundi 400, mpata woperekera umachepetsedwa kufika pa mainchesi 0.0002, zomwe zimaletsa kuyenda kudzera mu mpatawo pansi pa 0.1 scfm. Kuwonjezeka kumeneku kwa choletsa chachiwiri kumapereka choletsa cholowera m'mphepete mwa msewu mokwanira kuti chilole kupanikizika kwapakati pa mpatawo kukwera kufika pa 40 psi ndikuthandizira katundu wowonjezeka.
Iyi ndi mbali yowonekera ya mpweya wozungulira womwe umapezeka mu makina oyezera (CMM). Ngati makina ozungulira mpweya akuwoneka ngati "wozungulira mpweya wokwanira" ayenera kukhala ndi choletsa pamwamba pa choletsa cha mpweya wozungulira.
Kulipira kwa Orifice vs. Porous Compensation
Kubwezera kwa orifice ndi njira yodziwika kwambiri yobwezera. Orifice wamba akhoza kukhala ndi mainchesi 0.010 m'mimba mwake, koma popeza akudyetsa mainchesi angapo, amadyetsa malo ambiri kuposa iye mwini, kotero liwiro la mpweya likhoza kukhala lalikulu. Nthawi zambiri, orifice amadulidwa bwino kuchokera ku rubies kapena safiro kuti apewe kuwonongeka kwa kukula kwa orifice ndipo motero kusintha kwa magwiridwe antchito a bearing. Vuto lina ndilakuti pamipata yochepera mainchesi 0.0002, malo ozungulira orifice amayamba kuletsa kuyenda kwa madzi kupita kunkhope yonse, pomwe filimu ya gasi imagwa. Zomwezo zimachitikanso pamene mpweya wachotsedwa, chifukwa malo a orifice ndi mizere iliyonse ndi omwe amapezeka kuti ayambitse kukweza. Ichi ndi chimodzi mwa zifukwa zazikulu zomwe ma bearing opanikizika akunja samawonekera mu mapulani osindikizira.
Izi sizili choncho pa bere lokhala ndi porous completed bearing, m'malo mwake kuuma kumapitirirabe
Kuwonjezeka pamene katundu akuwonjezeka ndipo kusiyana kumachepa, monga momwe zilili ndi DGS (Chithunzi 1) ndi
ma bearing amafuta a hydrodynamic. Pankhani ya ma bearing akunja okhala ndi porous, bearing idzakhala mu balanced force mode pamene input pressure imachulukitsa dera lomwe likufanana ndi katundu wonse pa bearing. Iyi ndi nkhani yosangalatsa ya tribological chifukwa pali zero lift kapena air gap. Padzakhala zero flow, koma hydrostatic force ya air pressure motsutsana ndi counter surface pansi pa bearing imachotsabe kulemera kwa katundu wonse ndipo imabweretsa pafupifupi zero coefficient of friction—ngakhale kuti nkhopezo zikukhudzanabe.
Mwachitsanzo, ngati nkhope ya graphite seal ili ndi malo okwana mainchesi 10 ndi mphamvu yotseka yokwana mapaundi 1,000 ndipo graphite ili ndi mphamvu yokwanira ya 0.1, ingafunike mphamvu yokwana mapaundi 100 kuti iyambe kuyenda. Koma ndi mphamvu yakunja ya 100 psi yomwe imadutsa mu graphite yomwe ili ndi mapokoso kupita kumaso kwake, sipadzakhala mphamvu yofunikira kuti iyambe kuyenda. Izi zili choncho ngakhale kuti pakadali mphamvu yotseka yokwana mapaundi 1,000 yomwe imakanikiza nkhope ziwirizo pamodzi ndipo nkhopezo zikukhudzana.
Gulu la zipangizo zonyamula zinthu monga: graphite, carbons ndi ceramics monga alumina ndi silicon-carbides zomwe zimadziwika ndi mafakitale a turbo ndipo zimakhala ndi ma pore mwachilengedwe kotero kuti zitha kugwiritsidwa ntchito ngati ma bearing opanikizika akunja omwe ndi ma bearing a filimu yamadzimadzi osalumikizana. Pali ntchito yosakanikirana pomwe kupanikizika kwakunja kumagwiritsidwa ntchito kuchepetsa kupsinjika kwa kukhudzana kapena mphamvu yotseka ya chisindikizo kuchokera ku tribology yomwe ikuchitika m'maso mwa chisindikizo cholumikizana. Izi zimathandiza woyendetsa pampu kusintha china chake kunja kwa pampu kuti athe kuthana ndi mavuto omwe akugwiritsidwa ntchito komanso kuthamanga kwambiri pogwiritsa ntchito zisindikizo zamakina.
Mfundo imeneyi imagwiranso ntchito pa maburashi, ma commutator, ma exciter, kapena contactor iliyonse yolumikizirana yomwe ingagwiritsidwe ntchito kutenga deta kapena magetsi pa zinthu zozungulira kapena kuzimitsa. Pamene ma rotor akuzungulira mofulumira ndikutha mphamvu akuwonjezeka, zimakhala zovuta kusunga zipangizozi kuti zigwirizane ndi shaft, ndipo nthawi zambiri zimakhala zofunikira kuwonjezera mphamvu ya spring yomwe imawagwira motsutsana ndi shaft. Mwatsoka, makamaka pankhani yogwira ntchito mwachangu, kuwonjezeka kwa mphamvu yolumikizirana kumeneku kumabweretsanso kutentha ndi kuwonongeka kwambiri. Mfundo yofananayo yosakanikirana yomwe imagwiritsidwa ntchito pa nkhope zosindikizira zamakina zomwe zafotokozedwa pamwambapa ingagwiritsidwenso ntchito pano, komwe kukhudzana kwakuthupi kumafunika kuti magetsi ayendetsedwe pakati pa zigawo zosasunthika ndi zozungulira. Kupanikizika kwakunja kungagwiritsidwe ntchito ngati kupanikizika kuchokera ku silinda ya hydraulic kuti achepetse kukangana pa mawonekedwe osinthika pamene akuwonjezera mphamvu ya spring kapena mphamvu yotseka yomwe imafunika kuti burashi kapena nkhope yosindikizira igwirizane ndi shaft yozungulira.
Nthawi yotumizira: Okutobala-21-2023