Ama-double booster pump air seal, aguqulelwe kubuchwepheshe be-compressor air seal, avame kakhulu embonini ye-shaft seal.Lezi zimpawu zihlinzeka ngokukhishwa okuyiziro koketshezi olumpontshwa emkhathini, zinikeza ukumelana okuncane kokungqubuzana ku-shaft yepompo futhi zisebenze ngohlelo olulula lokusekela.Lezi zinzuzo zinikeza izindleko eziphansi zomjikelezo wokuphila wesixazululo.
Lezi zimpawu zisebenza ngokwethula umthombo wangaphandle wegesi enomfutho phakathi kwezindawo zokuvala zangaphakathi nezingaphandle.I-Topography ethile yendawo yokuvala ibeka ingcindezi eyengeziwe kugesi ovimbelayo, okwenza indawo yokuvala ihlukane, okwenza indawo yokuvala intante kufilimu yegesi.Ukulahleka kwefriction kuphansi njengoba izindawo zokuvala zingasathinti.I-barrier gas idlula kulwelwesi ngesilinganiso esiphansi sokugeleza, idla i-barrier gas ngendlela yokuvuza, iningi lakhona elivuza emkhathini ngokusebenzisa izindawo ezingaphandle ze-seal.Izinsalela zingena egumbini lezigxivizo futhi ekugcineni zithathwe umfudlana wenqubo.
Zonke izimpawu ze-hermetic eziphindwe kabili zidinga uketshezi olucindezelwe (uketshezi noma igesi) phakathi kwezindawo zangaphakathi nezingaphandle zokuhlanganiswa kophawu lwemishini.Kudingeka uhlelo lokusekela ukuze kuhanjiswe lolu ketshezi esigxivizweni.Ngokuphambene, ku-liquid lubricated pressure double seal, uketshezi oluvimbelayo luzungeza lusuka ku-reservoir ngokusebenzisa uphawu lomshini, lapho lugcoba khona indawo yophawu, lumunce ukushisa, futhi lubuyele endaweni yokugcina amanzi lapho ludinga ukuqeda ukushisa okumuncwe.Lezi zinhlelo zokusekela umfutho wegazi okabili ziyinkimbinkimbi.Imithwalo eshisayo ikhuphuka ngokucindezela kwenqubo kanye nezinga lokushisa futhi ingabangela izinkinga zokuthembeka uma ingabalwa kahle futhi isethwe.
Isistimu yokusekela izigxivizo zomoya ocindezelweyo ithatha indawo encane, ayidingi amanzi okupholisa, futhi idinga ukulungiswa okuncane.Ngaphezu kwalokho, lapho umthombo onokwethenjelwa wokuvikela igesi utholakala, ukwethembeka kwawo kuzimele ekucindezelweni kwenqubo nokushisa.
Ngenxa yokwamukelwa okukhulayo kwezimpawu zomoya zephampu yengcindezi ekabili emakethe, i-American Petroleum Institute (API) yengeze Uhlelo 74 njengengxenye yokushicilelwa kohlelo lwesibili lwe-API 682.
74 Uhlelo olusekelayo lohlelo ngokuvamile luyisethi yamageji abekwe ngamaphaneli namavalvu ahlanza igesi evimbelayo, alawule ukucindezela okuya phansi komfula, futhi akale ingcindezi nokugeleza kwegesi kuya kuma-mechanical seals.Ukulandela indlela yegesi yokuvimbela ngokusebenzisa iphaneli ye-Plan 74, into yokuqala i-valve yokuhlola.Lokhu kuvumela ukunikezwa kwegesi yokuvimbela ukuba ihlukaniswe nophawu ukuze kushintshwe isici sokuhlunga noma ukulungiswa kwephampu.I-barrier gas ibe isidlula kusihlungi esihlanganisayo esingu-2 kuya ku-3 (µm) esibamba uketshezi nezinhlayiya ezingalimaza izici ze-topographical ze-seal surface, kwakheka ifilimu yegesi ebusweni bophawu.Lokhu kulandelwa isilawuli sokucindezela kanye ne-manometer yokubeka ingcindezi ye-barrier gas supply to the mechanical seal.
Izigxivizo zegesi yephampu yengcindezi ekabili zidinga ingcindezi yokuhlinzeka ngegesi evimbelayo ukuze ihlangabezane noma yeqe ingcindezi encane yokuhluka ngaphezu kokucindezela okukhulu egumbini lophawu.Lokhu kwehla kwengcindezi encane kuyehluka kumkhiqizi wezimpawu nohlobo, kodwa ngokuvamile kungamaphawundi angama-30 iyintshi yesikwele (psi).Umshini wokucindezela usetshenziselwa ukuthola noma yiziphi izinkinga ngengcindezi yokuhlinzeka ngegesi yokuvimbela futhi ukhale i-alamu uma ukucindezela kwehla ngaphansi kwenani eliphansi.
Ukusebenza kophawu kulawulwa yi-barrier gas flow usebenzisa imitha yokugeleza.Ukuchezuka kusuka kumazinga okugeleza kwegesi yophawu olubikwe abakhiqizi bezimpawu zemishini kubonisa ukusebenza okuncishisiwe kokuvala.Ukugeleza kwegesi yokuvimbela okuncishisiwe kungase kube ngenxa yokuzungezisa iphampu noma ukuthuthela koketshezi kubuso be-seal (kusuka kugesi evimbela ukungcoliswa noma uketshezi olucutshungulwayo).
Ngokuvamile, ngemva kwezenzakalo ezinjalo, ukulimala ezindaweni zokuvala kwenzeka, bese ukugeleza kwegesi yokuvimbela kuyanda.Ukwenyuka kwengcindezi empompini noma ukulahlekelwa ingxenye yokucindezela kwegesi evimbelayo nakho kungalimaza indawo yokuvala.Ama-alamu ageleza kakhulu angasetshenziswa ukucacisa lapho kudingeka ukungenelela ukuze kulungiswe ukugeleza kwegesi ephezulu.I-setpoint ye-alamu egeleza kakhulu ngokuvamile iba sebangeni le-10 ukuya kweziyi-100 lokugeleza kwegesi yokuvimbela evamile, ngokuvamile ayinqunywa umkhiqizi womshini wophawu, kodwa kuya ngokuthi ingakanani ukuvuza kwegesi iphampu engakwazi ukukubekezelela.
Kusetshenziswe ama-flowmeters e-gauge aguquguqukayo ngokwesiko futhi akuvamile ukuthi ama-flowmeters aphansi futhi aphakeme axhunywe ochungechungeni.Iswishi egeleza kakhulu ingase ifakwe kumitha yokugeleza kwebanga eliphezulu ukuze kunikezwe i-alamu yokugeleza okuphezulu.Ama-flowmeters wendawo eguquguqukayo angalinganiswa kuphela kumagesi athile kumazinga okushisa athile nezingcindezi.Uma usebenza ngaphansi kwezinye izimo, njengokushintshashintsha kwezinga lokushisa phakathi kwehlobo nobusika, izinga lokugeleza elibonisiwe alikwazi ukubhekwa njengenani elinembile, kodwa liseduze nenani langempela.
Ngokukhishwa kwe-API 682 4th edition, ukugeleza nokukalwa kwengcindezi kusuke ku-analog kuya kudijithali ngokufundwa kwendawo.Ama-flowmeters edijithali angasetshenziswa njengama-flowmeters endawo aguquguqukayo, aguqula indawo yokuntanta ibe amasignali edijithali, noma ama-flowmeters amaningi, aguqula ngokuzenzakalelayo ukugeleza kobuningi kube ukugeleza kwevolumu.Isici esihlukanisayo sama-transmitter okugeleza okukhulu ukuthi ahlinzeka ngokuphumayo okunxephezela ingcindezi nezinga lokushisa ukuze kunikeze ukugeleza kwangempela ngaphansi kwezimo ezijwayelekile zomkhathi.Okubi ukuthi la madivayisi abiza kakhulu kunezindawo eziguquguqukayo ze-flowmeters.
Inkinga ngokusebenzisa i-flow transmitter ukuthola i-transmitter ekwazi ukukala ukugeleza kwegesi evimbelayo ngesikhathi sokusebenza okujwayelekile nasemaphoyinti e-alamu ageleza kakhulu.Izinzwa ezigelezayo zinamanani aphezulu naphansi angafundwa ngokunembile.Phakathi kokugeleza okunguziro kanye nenani elincane, ukugeleza kokuphumayo kungase kungabi nembayo.Inkinga iwukuthi njengoba izinga lokugeleza eliphezulu lemodeli ethile ye-transducer yokugeleza likhuphuka, izinga lokugeleza elincane nalo liyakhula.
Isixazululo esisodwa ukusebenzisa ama-transmitter amabili (imvamisa eyodwa ephansi kanye nemvamisa eyodwa ephezulu), kepha lena inketho ebizayo.Indlela yesibili iwukusebenzisa inzwa yokugeleza yebanga lokugeleza elivamile futhi usebenzise iswishi yokugeleza okuphezulu enemitha yokugeleza ye-analog yobubanzi obuphezulu.Ingxenye yokugcina igesi yokuvimbela idlula i-valve yokuhlola ngaphambi kokuba igesi yokuvimbela ishiye iphaneli futhi ixhume uphawu lwemishini.Lokhu kuyadingeka ukuze kuvinjwe ukugeleza emuva koketshezi olupompowe kuphaneli kanye nokulimala kwethuluzi uma kwenzeka ukuphazamiseka kwenqubo okungavamile.
I-valve yokuhlola kufanele ibe nengcindezi yokuvula ephansi.Uma ukukhethwa kungalungile, noma uma uphawu lomoya lwepompo yokucindezela okubili lunokugeleza kwegesi okuvinjiwe okuphansi, kungabonakala ukuthi ukushaywa kwegesi yokuvimbela ukugeleza kubangelwa ukuvulwa nokuvuselelwa kabusha kwe-valve yokuhlola.
Ngokuvamile, i-nitrogen yezitshalo isetshenziswa njengegesi evimbelayo ngoba itholakala kalula, inezinti futhi ayibangeli ukusabela kwamakhemikhali okubi oketshezini olumpontshwayo.Amagesi angenayo angatholakali, njenge-argon, angasetshenziswa.Ezimeni lapho umfutho wegesi ovikelayo umkhulu kunomfutho we-nitrogen wesitshalo, i-pressure booster ingakhuphula ingcindezi futhi igcine igesi yomfutho ophezulu kumamukeli oxhunywe ku-Plan 74 panel inlet.Amabhodlela e-nitrogen asemabhodleleni ngokuvamile awanconywa ngoba adinga ukushintshwa njalo kwamasilinda angenalutho kufakwe agcwele.Uma izinga le-seal liwohloka, ibhodlela lingasuswa ngokushesha, okubangela ukuthi iphampu ime ukuze kuvinjwe umonakalo owengeziwe kanye nokwehluleka kophawu lwemishini.
Ngokungafani nezinhlelo zokuvimbela uketshezi, amasistimu asekelayo we-Plan 74 awadingi ukuba seduze kwezimpawu zemishini.Okuwukuphela kwe-caveat lapha ingxenye enwetshiwe yeshubhu elincane lobubanzi.Ukwehla kwengcindezi phakathi kwephaneli ye-Plan 74 kanye nophawu kungenzeka epayipini ngezikhathi zokugeleza okuphezulu (ukuwohloka kwe-seal), okunciphisa ingcindezi yokuvimbela etholakalayo ocingweni.Ukwandisa ubukhulu bepayipi kungaxazulula le nkinga.Njengomthetho, amaphaneli we-Plan 74 afakwe endaweni yokuma endaweni efanelekile yokulawula ama-valve nokufunda ithuluzi lokufunda.Abakaki bangafakwa kupuleti lesisekelo sepompo noma eduze kwepompo ngaphandle kokuphazamisa ukuhlolwa nokugcinwa kwepompo.Gwema izingozi ezikhubekayo kumapayipi/amapayipi axhuma amaphaneli e-Plan 74 anezigxivizo zemishini.
Kumaphampu ane-inter-bearing anezimpawu ezimbili zemishini, eyodwa ekugcineni kwepompo, akukhuthazwa ukusebenzisa iphaneli eyodwa kanye nokuhlukanisa igesi yokuvimbela igesi kuphawu ngalunye lomshini.Isixazululo esinconyiwe ukusebenzisa iphaneli ehlukile ye-Plan 74 yophawu ngalunye, noma iphaneli ye-Plan 74 enemiphumela emibili, ngayinye enesethi yayo yama-flowmeters namaswishi agelezayo.Ezindaweni ezinobusika obubandayo kungase kudingeke ukuthi kudlule ubusika amaphaneli e-Plan 74.Lokhu kwenziwa ngokuyinhloko ukuze kuvikelwe izinto zikagesi zephaneli, ngokuvamile ngokufaka iphaneli kukhabhinethi nokwengeza izinto zokushisa.
Into ethokozisayo ukuthi izinga lokugeleza kwegesi elivimbelayo liyakhuphuka ngokuncipha kwezinga lokushisa lokuhlinzekwa kwegesi evimbelayo.Lokhu ngokuvamile akunakwa, kodwa kungabonakala ezindaweni ezinobusika obubandayo noma umehluko omkhulu wezinga lokushisa phakathi kwehlobo nobusika.Kwezinye izimo, kungase kudingeke ukuthi ulungise indawo yokubeka i-alamu egeleza kakhulu ukuze uvimbele ama-alamu amanga.Amapayipi omoya amaphaneli namapayipi/amapayipi axhumayo kufanele ahlanzwe ngaphambi kokufaka amaphaneli e-Plan 74 ekusebenzeni.Lokhu kufinyelelwa kalula kakhulu ngokungeza i-valve yokukhipha umoya eduze noma eduze noxhumano lomshini wophawu.Uma i-valve yokopha ingatholakali, isistimu ingahlanzwa ngokunqamula ishubhu/ishubhu ku-mechanical seal bese iphinda ixhumeke ngemva kokuhlanza.
Ngemva kokuxhuma amaphaneli e-Plan 74 kuma-seal kanye nokuhlola konke ukuxhumeka kokuvuza, isilawuli sokucindezela manje singalungiswa ekucindezelweni okumisiwe ekusetshenzisweni.Iphaneli kufanele inikeze igesi yokuvimbela ukucindezela ocingweni lwemishini ngaphambi kokugcwalisa iphampu ngoketshezi lwenqubo.Izigxivizo namaphaneli e-Plan 74 sezilungele ukuqala lapho ukugunyazwa kwephampu nokukhipha umoya sekuqediwe.
Isici sokuhlunga kufanele sihlolwe ngemva kwenyanga yokusebenza noma njalo ngemva kwezinyanga eziyisithupha uma kungatholakali ukungcola.Isikhathi sokushintsha isihlungi sizoncika ekuhlanzekeni kwegesi enikeziwe, kodwa akufanele sidlule iminyaka emithathu.
Izilinganiso zegesi yokuvimbela kufanele zihlolwe futhi zirekhodwe ngesikhathi sokuhlolwa okujwayelekile.Uma isivimbelo sokugeleza komoya esibangelwa ukuvulwa nokuvalwa kwevalvu yokuhlola kukhulu ngokwanele ukuze kuqalise i-alamu yokugeleza okuphezulu, lawa manani e-alamu angase adinge ukunyuswa ukuze agweme ama-alamu angamanga.
Isinyathelo esibalulekile ekuqedeni ukusebenza ukuthi ukuhlukaniswa nokucindezeleka kwegesi evikelayo kufanele kube isinyathelo sokugcina.Okokuqala, hlukanisa futhi ucindezele isikhwama sepompo.Uma iphampu isesimweni esiphephile, ingcindezi yokuhlinzeka ngegesi evikelayo ingavalwa futhi ingcindezi yegesi isuswe epayipini elixhuma iphaneli ye-Plan 74 kuphawu lomshini.Khipha lonke uketshezi ohlelweni ngaphambi kokuqala noma yimuphi umsebenzi wokulungisa.
Izimpawu zomoya zephampu yengcindezi ekabili ehlanganiswe nezinhlelo zokusekela ze-Plan 74 zinikeza opharetha isisombululo se-zero-emission shaft seal, ukutshalwa kwezimali okuyimali ephansi (uma kuqhathaniswa nama-seal anezinhlelo zokuvimbela uketshezi), izindleko ezincishisiwe zomjikelezo wokuphila, isisekelo sohlelo oluncane lokusekela kanye nezidingo zesevisi encane.
Uma ifakiwe futhi isetshenziswa ngokuhambisana nokusebenza okungcono kakhulu, lesi sixazululo sokuqukatha singanikeza ukwethembeka kwesikhathi eside futhi sikhulise ukutholakala kwemishini ejikelezayo.
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UMark Savage ungumphathi weqembu lomkhiqizo eJohn Crane.USavage uneziqu zeBachelor of Science in Engineering azithola eNyuvesi yaseSydney, e-Australia.Ukuze uthole olunye ulwazi vakashela johcrane.com.
Isikhathi sokuthumela: Sep-08-2022