Izivalo zomoya zepompo yokuqinisa kabili, ezithathwe kubuchwepheshe be-compressor air seal, zivame kakhulu embonini yezivalo ze-shaft. Lezi zivalo azikhiphi lutho oluphumayo emoyeni, zinikeza ukumelana okuncane kokungqubuzana emshafini wepompo futhi zisebenza ngohlelo lokusekela olulula. Lezi zinzuzo zinikeza izindleko eziphansi zomjikelezo wokuphila kwesixazululo.
Lezi zivalo zisebenza ngokungenisa umthombo wangaphandle wegesi ecindezelwe phakathi kwezindawo zokuvala zangaphakathi nezangaphandle. I-topography ethile yendawo yokuvala ibeka ingcindezi eyengeziwe kugesi yokuvimba, okwenza indawo yokuvala ihlukane, okwenza indawo yokuvala intante efilimini yegesi. Ukulahlekelwa kokungqubuzana kuphansi njengoba izindawo zokuvala zingasathinti. Igesi yokuvimba idlula elwengeni ngesivinini sokugeleza esiphansi, idle igesi yokuvimba ngendlela yokuvuza, iningi layo elivuza liye emkhathini ngezindawo zokuvala zangaphandle. Izinsalela zingena ekamelweni lokuvala futhi ekugcineni zithwalwa umfula wenqubo.
Zonke izivalo eziphindwe kabili ezivalekile zidinga uketshezi olucindezelwe (uketshezi noma igesi) phakathi kwezindawo zangaphakathi nezangaphandle zenhlangano yesivalo semishini. Kudingeka uhlelo lokusekela ukuze kuhanjiswe lolu ketshezi esivaloni. Ngokuphambene nalokho, esivaloni esiphindwe kabili esivalweni sokucindezela esinoketshezi, uketshezi oluvimbelayo lujikeleza lusuka esibayeni ludlule esivaloni somshini, lapho lugcoba khona izindawo zesivalo, lumunce ukushisa, bese lubuyela esibayeni lapho ludinga khona ukuqeda ukushisa okumuncwe. Lezi zinhlelo zokusekela isivalo esiphindwe kabili esivalweni sokucindezela uketshezi ziyinkimbinkimbi. Imithwalo yokushisa iyanda ngokucindezela kwenqubo kanye nokushisa futhi ingabangela izinkinga zokuthembeka uma ingabalwa futhi ibekwe kahle.
Uhlelo lokusekela isivalo esiphindwe kabili somoya olucindezelwe aluthathi isikhala esiningi, aludingi manzi okupholisa, futhi aludingi ukulungiswa okuningi. Ngaphezu kwalokho, lapho umthombo othembekile wegesi yokuvikela utholakala, ukuthembeka kwawo akuxhomekile ekucindezelweni kwenqubo kanye nokushisa.
Ngenxa yokwamukelwa okwandayo kwezivalo zomoya zepompo yokucindezela ezimbili emakethe, i-American Petroleum Institute (API) yengeze i-Program 74 njengengxenye yokushicilelwa kohlelo lwesibili lwe-API 682.
74 Uhlelo lokusekela uhlelo ngokuvamile luyisethi yama-gauge nama-valve afakwe kumaphaneli ahlanza igesi yokuvimbela, alawule ingcindezi engezansi, futhi alinganise ingcindezi kanye nokugeleza kwegesi kuya ezivalweni zemishini. Ukulandela indlela yegesi yokuvimbela ngephaneli ye-Plan 74, into yokuqala yi-valve yokuhlola. Lokhu kuvumela ukuthi ukuhlinzekwa kwegesi yokuvimbela kuhlukaniswe nesivalo ukuze kufakwe isihlungi noma kulungiswe iphampu. Igesi yokuvimbela ibe isidlula esihlungini sokuhlanganisa esingu-2 kuya ku-3 micrometer (µm) esibamba uketshezi kanye nezinhlayiya ezingalimaza izici zesimo sendawo yokuvimba, kwakha ifilimu yegesi ebusweni bokuvimba. Lokhu kulandelwa umlawuli wokucindezela kanye ne-manometer yokusetha ingcindezi yokuhlinzekwa kwegesi yokuvimbela esivalweni semishini.
Izivalo zegesi zephampu yokucindezela ezimbili zidinga ingcindezi yokuphakelwa kwegesi yokuvimbela ukuthi ihlangabezane noma idlule ingcindezi encane yomehluko ngaphezu kwengcindezi ephezulu ekamelweni lokuvala. Lokhu kwehla kwengcindezi encane kuyahlukahluka kuye ngomkhiqizi wesivalo kanye nohlobo, kodwa ngokuvamile kuba cishe amakhilogremu angu-30 nge-intshi yesikwele (psi). Iswishi yokucindezela isetshenziselwa ukuthola noma yiziphi izinkinga ngengcindezi yokuphakelwa kwegesi yokuvimbela futhi izwakalise i-alamu uma ingcindezi yehla ngaphansi kwenani eliphansi.
Ukusebenza kwesivalo kulawulwa ukugeleza kwegesi yesivalo kusetshenziswa imitha yokugeleza. Ukuphambuka emazingeni okugeleza kwegesi yesivalo okubikwe abakhiqizi besivalo semishini kubonisa ukusebenza okunciphile kokuvala. Ukugeleza kwegesi yesivalo okunciphile kungase kubangelwe ukujikeleza kwephampu noma ukufuduka koketshezi ebusweni besivalo (kusuka kugesi yesivalo esingcolisiwe noma uketshezi lwenqubo).
Ngokuvamile, ngemva kwezehlakalo ezinjalo, kwenzeka umonakalo ezindaweni zokuvala, bese ukugeleza kwegesi evimbelayo kuyanda. Ukwanda komfutho empompini noma ukulahlekelwa okuyingxenye komfutho wegesi evimbelayo nakho kungalimaza indawo yokuvala. Ama-alamu okugeleza okuphezulu angasetshenziswa ukunquma ukuthi kudingeka nini ukungenelela ukulungisa ukugeleza kwegesi ephezulu. Indawo ebekwe kuyo i-alamu yokugeleza okuphezulu ngokuvamile iphakathi kwezikhathi eziyi-10 kuya kweziyi-100 zokugeleza kwegesi evimbelayo evamile, ngokuvamile enganqunywa umenzi wesivalo semishini, kodwa kuncike ekutheni ipompo ingakubekezelela ukuvuza kwegesi okungakanani.
Ngokwesiko kuye kwasetshenziswa ama-flowmeter aguquguqukayo futhi akuvamile ukuthi ama-flowmeter aphansi naphezulu axhunywe ngokulandelana. Iswishi yokugeleza ephezulu ingabe isifakwa ku-flowmeter yebanga eliphezulu ukuze inikeze i-alamu yokugeleza ephezulu. Ama-flowmeter endawo aguquguqukayo angalinganiswa kuphela ngamagesi athile emazingeni okushisa athile kanye nokucindezela. Uma esebenza ngaphansi kwezinye izimo, njengokushintshashintsha kwezinga lokushisa phakathi kwehlobo nobusika, izinga lokugeleza elibonisiwe alikwazi ukubhekwa njengenani elinembile, kodwa liseduze nenani langempela.
Ngokukhishwa kwe-API 682 uhlelo lwesine, izilinganiso zokugeleza nokucindezela ziye zashintsha kusuka ku-analog kuya kudijithali ngokufundwa kwendawo. Ama-flowmeter edijithali angasetshenziswa njenge-variable area flowmeters, aguqula indawo yokuntanta ibe yizibonakaliso zedijithali, noma ama-mass flowmeters, aguqula ngokuzenzakalelayo ukugeleza kwesisindo kube ukugeleza kwevolumu. Isici esihlukanisayo sama-mass flow transmitters ukuthi ahlinzeka ngemiphumela ekhokhela ingcindezi kanye nokushisa ukuze ahlinzeke ukugeleza kwangempela ngaphansi kwezimo ezijwayelekile zomkhathi. Okubi ukuthi la madivayisi abiza kakhulu kune-variable area flowmeters.
Inkinga yokusebenzisa i-flow transmitter ukuthola i-transmitter ekwazi ukukala ukugeleza kwegesi okuvimbelwe ngesikhathi sokusebenza okuvamile kanye nasezindaweni zokuxwayisa ukugeleza okuphezulu. Izinzwa zokugeleza zinenani eliphakeme neliphansi kakhulu elingafundwa ngokunembile. Phakathi kokugeleza okungu-zero nenani eliphansi kakhulu, ukugeleza kokukhipha kungenzeka kungabi okunembile. Inkinga iwukuthi njengoba izinga lokugeleza eliphezulu kakhulu lemodeli ethile ye-flow transducer landa, izinga lokugeleza eliphansi kakhulu nalo liyakhula.
Isixazululo esisodwa ukusebenzisa ama-transmitter amabili (elinye imvamisa ephansi nelinye imvamisa ephezulu), kodwa lokhu kuyindlela ebiza kakhulu. Indlela yesibili ukusebenzisa inzwa yokugeleza kwebanga lokugeleza elijwayelekile lokusebenza bese usebenzisa iswishi yokugeleza ephezulu ene-analog flow meter ephezulu. Ingxenye yokugcina igesi evimbelayo edlula kuyo yi-valve yokuhlola ngaphambi kokuba igesi evimbelayo ishiye iphaneli bese ixhuma esivikelweni somshini. Lokhu kuyadingeka ukuvimbela ukugeleza koketshezi olupompiwe kuphaneli kanye nomonakalo wethuluzi uma kwenzeka ukuphazamiseka kwenqubo okungavamile.
Ivalvu yokuhlola kumele ibe nomfutho ophansi wokuvula. Uma ukukhetha kungalungile, noma uma uphawu lomoya lwephampu yokucindezela okubili lunokugeleza kwegesi yokuvimbela okuphansi, kungabonakala ukuthi ukushaya kwegesi yokuvimbela kubangelwa ukuvulwa nokufakwa kabusha kwevalvu yokuhlola.
Ngokuvamile, i-nitrogen yezitshalo isetshenziswa njengegesi yokuvimbela ngoba itholakala kalula, ayisebenzi futhi ayibangeli noma yikuphi ukusabela kwamakhemikhali okubi kuketshezi olupompiwe. Amagesi angasebenzi angatholakali, njenge-argon, angasetshenziswa futhi. Ezimweni lapho umfutho wegesi ovikelayo odingekayo umkhulu kunomfutho we-nitrogen yezitshalo, i-pressure booster ingandisa umfutho futhi igcine igesi yomfutho ophezulu ku-receiver exhunywe ku-Plan 74 panel inlet. Amabhodlela e-nitrogen asemabhodleleni ngokuvamile awanconywa njengoba edinga ukufaka njalo amasilinda angenalutho ngama-full cylinders. Uma ikhwalithi yesivalo iwohloka, ibhodlela lingasuswa ngokushesha, okubangela ukuthi ipompo ime ukuze kuvinjelwe umonakalo owengeziwe kanye nokwehluleka kwesivalo somshini.
Ngokungafani nezinhlelo zokuvimbela uketshezi, izinhlelo zokusekela ze-Plan 74 azidingi ukusondela eduze kwezivalo zomshini. Okuwukuphela kwesizathu lapha yisigaba eside sepayipi elincane elinobubanzi. Ukwehla kwengcindezi phakathi kwephaneli ye-Plan 74 kanye nesivalo kungenzeka epayipini ngezikhathi zokugeleza okuphezulu (ukuwohloka kwesivalo), okunciphisa ingcindezi yesivalo etholakalayo esivaloni. Ukwandisa usayizi wepayipi kungaxazulula le nkinga. Njengomthetho, amaphaneli e-Plan 74 afakwa esitendini endaweni ephakeme elula yokulawula ama-valve kanye nokufundwa kwezinsimbi zokufunda. Ibhulakhethi lingafakwa epuletini lesisekelo sepompo noma eduze kwepompo ngaphandle kokuphazamisa ukuhlolwa nokugcinwa kwepompo. Gwema izingozi zokukhubeka emapayipini/amapayipi axhuma amaphaneli e-Plan 74 ngezivalo zomshini.
Kumaphampu ahlanganisayo anezivalo ezimbili zemishini, eyodwa ekugcineni ngakunye kwephampu, akukhuthazwa ukusebenzisa iphaneli elilodwa kanye nokuhlukanisa i-barrier gas outlet ku-seal ngayinye yemishini. Isixazululo esinconywayo ukusebenzisa iphaneli ehlukile ye-Plan 74 ku-seal ngayinye, noma iphaneli ye-Plan 74 eneziphuma ezimbili, ngayinye inesethi yayo yama-flowmeter kanye nama-flow switch. Ezindaweni ezinobusika obubandayo kungadingeka ukuthi amaphaneli e-Plan 74 adlule ebusika. Lokhu kwenziwa ngokuyinhloko ukuvikela imishini kagesi yephaneli, ngokuvamile ngokufaka iphaneli ekhabhinethi nokwengeza izinto zokushisa.
Isenzakalo esithakazelisayo ukuthi izinga lokugeleza kwegesi evimbelayo liyakhula ngokuncipha kwezinga lokushisa lokunikezwa kwegesi evimbelayo. Lokhu kuvame ukunganakwa, kodwa kungabonakala ezindaweni ezinobusika obubandayo noma umehluko omkhulu wokushisa phakathi kwehlobo nobusika. Kwezinye izimo, kungadingeka ukulungisa indawo yokusetha i-alamu yokugeleza okuphezulu ukuze kuvinjelwe ama-alamu angamanga. Amapayipi omoya wephaneli namapayipi/amapayipi axhumanisayo kumele ahlanzwe ngaphambi kokufaka amaphaneli e-Plan 74 ekusebenzeni. Lokhu kufezwa kalula ngokufaka i-vent valve eduze noma eduze kokuxhumeka kwe-mechanical seal. Uma i-blood valve ingatholakali, uhlelo lungahlanzwa ngokunqamula ipayipi/ithubhu esivalweni semishini bese luphinde luxhunywe kabusha ngemva kokuhlanza.
Ngemva kokuxhuma amaphaneli e-Plan 74 ezivalweni nokuhlola konke ukuxhumana ukuthi akunawo yini amapayipi, isilawuli sokucindezela manje singalungiswa kungcindezi ebekwe ekusetshenzisweni. Iphaneli kumele inikeze igesi yokuvimbela ecindezelwe esivalweni somshini ngaphambi kokugcwalisa ipompo ngoketshezi lwenqubo. Izivalo namaphaneli e-Plan 74 asekulungele ukuqala lapho izinqubo zokuqalisa nokukhipha umoya wepompo seziqediwe.
Ingxenye yesihlungi kumele ihlolwe ngemva kwenyanga yokusebenza noma njalo ezinyangeni eziyisithupha uma kungatholakali ukungcola. Isikhathi sokushintsha isihlungi sizoncika ekuhlanzekeni kwegesi enikezwayo, kodwa akufanele sidlule iminyaka emithathu.
Amazinga egesi e-barrier kufanele ahlolwe futhi aqoshwe ngesikhathi sokuhlolwa okuvamile. Uma ukugeleza komoya we-barrier okubangelwa ukuvulwa nokuvalwa kwe-check valve kukhulu ngokwanele ukuqala i-alamu yokugeleza okuphezulu, lawa manani e-alamu angadinga ukukhushulwa ukuze kugwenywe ama-alamu angamanga.
Isinyathelo esibalulekile ekususeni ukusebenza ukuthi ukuhlukaniswa kanye nokunciphisa ukucindezeleka kwegesi yokuvikela kufanele kube yisinyathelo sokugcina. Okokuqala, hlukanisa futhi unciphise ukucindezeleka kwesikhwama sephampu. Uma iphampu isisesimweni esiphephile, umfutho wokuphakelwa kwegesi yokuvikela ungacinywa futhi umfutho wegesi ususwe epayipini elixhumanisa iphaneli ye-Plan 74 nesivalo somshini. Khipha lonke uketshezi ohlelweni ngaphambi kokuqala noma yimuphi umsebenzi wokulungisa.
Izivalo zomoya zepompo yokucindezela ezimbili ezihlanganiswe nezinhlelo zokusekela ze-Plan 74 zinikeza opharetha isisombululo sesivalo somgodi esingenawo ugesi, ukutshalwa kwezimali okuphansi (uma kuqhathaniswa nezivalo ezinezinhlelo zokuvimbela uketshezi), izindleko zomjikelezo wokuphila ezincishisiwe, indawo encane yokusekela uhlelo kanye nezidingo zesevisi ezincane.
Uma ifakiwe futhi isetshenziswa ngokuhambisana nomkhuba omuhle kakhulu, lesi sixazululo sokuvimbela singanikeza ukuthembeka kwesikhathi eside futhi sandise ukutholakala kwemishini ejikelezayo.
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UMark Savage ungumphathi weqembu lemikhiqizo eJohn Crane. USavage uneziqu zeBachelor of Science in Engineering ezivela eNyuvesi yaseSydney, e-Australia. Ukuze uthole ulwazi olwengeziwe vakashela ku-johncrane.com.
Isikhathi sokuthunyelwe: Septhemba-08-2022