Zisindikizo za mpweya zopopera mpweya zopopera mpweya kawiri, zomwe zasinthidwa kuchokera ku ukadaulo wa compressor air seal, ndizofala kwambiri mumakampani opopera mpweya. Zisindikizo izi sizimatulutsa madzi opopera mumlengalenga, sizimakanikiza kwambiri pa shaft ya pampu ndipo zimagwira ntchito ndi njira yosavuta yothandizira. Ubwino uwu umapereka mtengo wotsika wa yankho lonse.
Zisindikizo zimenezi zimagwira ntchito poika mpweya wopanikizika pakati pa malo otsekerera mkati ndi kunja. Malo enieni a malo otsekerera amaika mphamvu yowonjezera pa mpweya wotsekerera, zomwe zimapangitsa kuti malo otsekerera asiyane, zomwe zimapangitsa kuti malo otsekerera ayandame mu filimu ya mpweya. Kutayika kwa mphamvu kumakhala kochepa chifukwa malo otsekerera sakukhudzananso. Mpweya wotsekerera umadutsa mu nembanemba pamlingo wochepa wa madzi, n’kumadya mpweya wotsekerera mu mawonekedwe a kutuluka kwa madzi, omwe ambiri amatuluka mumlengalenga kudzera m’malo otsekerera akunja. Zotsalirazo zimalowa m’chipinda chotsekerera ndipo pamapeto pake zimatengedwa ndi mtsinje wa njira.
Zisindikizo zonse ziwiri zotsekedwa zimafuna madzi opanikizika (madzi kapena mpweya) pakati pa malo amkati ndi akunja a makina osindikizira. Dongosolo lothandizira limafunika kuti madzi awa aperekedwe ku chisindikizo. Mosiyana ndi zimenezi, mu chisindikizo chamadzimadzi chodzazidwa ndi madzi choponderezedwa, madzi otchinga amayendayenda kuchokera mu chisindikizo kudzera mu chisindikizo cha makina, komwe amathira mafuta pamwamba pa chisindikizo, kuyamwa kutentha, ndikubwerera ku chisindikizo komwe amafunika kutulutsa kutentha komwe kumayamwa. Machitidwe othandizira chisindikizo chamadzimadzi awa ndi ovuta. Kulemera kwa kutentha kumawonjezeka ndi kuthamanga kwa njira ndi kutentha ndipo kungayambitse mavuto odalirika ngati sikuwerengedwa bwino ndikukhazikitsidwa.
Dongosolo lothandizira chisindikizo cha mpweya wopanikizika limatenga malo ochepa, silifuna madzi ozizira, ndipo silifuna kukonza kwambiri. Kuphatikiza apo, ngati pali gwero lodalirika la mpweya woteteza, kudalirika kwake sikudalira kuthamanga kwa ntchito ndi kutentha.
Chifukwa cha kukhazikitsidwa kwa zisindikizo za mpweya zopopera mpweya ziwiri pamsika, American Petroleum Institute (API) idawonjezera Pulogalamu 74 ngati gawo la kufalitsa kwa kope lachiwiri la API 682.
74 Dongosolo lothandizira pulogalamu nthawi zambiri limakhala ndi ma gauge ndi ma valve okhala ndi panel omwe amatsuka mpweya wotchinga, kuwongolera kuthamanga kwa madzi, ndikuyesa kuthamanga kwa mpweya kupita ku zisindikizo zamakanika. Potsatira njira ya mpweya wotchinga kudzera mu gulu la Plan 74, chinthu choyamba ndi valavu yowunikira. Izi zimalola kuti mpweya wotchinga utuluke kuchokera ku chisindikizo kuti ulowe m'malo mwa chinthu chosinthira kapena kukonza pampu. Mpweya wotchinga umadutsa mu fyuluta yolumikizana ya maikromita awiri mpaka atatu (µm) yomwe imasunga madzi ndi tinthu tating'onoting'ono tomwe tingawononge mawonekedwe a pamwamba pa chisindikizo, ndikupanga filimu ya mpweya pamwamba pa chisindikizo. Izi zimatsatiridwa ndi chowongolera kuthamanga ndi manometer yokhazikitsira kuthamanga kwa mpweya wotchinga kupita ku chisindikizo chamakanika.
Zisindikizo za mpweya zotchingira mpweya ziwiri zimafuna kuti mphamvu ya mpweya wotchingira mpweya ikwaniritse kapena kupitirira mphamvu yocheperako kuposa mphamvu yayikulu mu chipinda chotchingira mpweya. Kutsika kochepa kwa mphamvu kumeneku kumasiyana malinga ndi wopanga ndi mtundu wa chisindikizo, koma nthawi zambiri kumakhala pafupifupi mapaundi 30 pa sikweya mainchesi (psi). Chosinthira mpweya chotchingira mpweya chimagwiritsidwa ntchito kuzindikira mavuto aliwonse ndi mphamvu ya mpweya wotchingira mpweya ndikuchenjeza ngati mphamvu ya mpweya yatsika pansi pa mtengo wocheperako.
Kugwira ntchito kwa chisindikizo kumayendetsedwa ndi mpweya wotchingira pogwiritsa ntchito choyezera kuyenda kwa madzi. Kupatuka kuchokera ku kuchuluka kwa mpweya wotchingira womwe wanenedwa ndi opanga zisindikizo zamakanika kumasonyeza kuchepa kwa magwiridwe antchito otchingira. Kuchepa kwa kuyenda kwa mpweya wotchingira kungakhale chifukwa cha kuzungulira kwa pampu kapena kusamuka kwa madzi kupita kumaso kwa chisindikizo (kuchokera ku mpweya wotchingira woipitsidwa kapena madzi ochizira).
Kawirikawiri, pambuyo pa zochitika zotere, kuwonongeka kwa malo otsekerera kumachitika, kenako mpweya wotchinga umawonjezeka. Kuthamanga kwa mpweya wotchinga kumawonjezeka mu pampu kapena kutayika pang'ono kwa mpweya wotchinga kungawonongenso malo otsekerera. Ma alamu othamanga kwambiri angagwiritsidwe ntchito kudziwa nthawi yomwe pakufunika kulowererapo kuti akonze mpweya wothamanga kwambiri. Malo okhazikitsira alamu yothamanga kwambiri nthawi zambiri amakhala pamtunda wa nthawi 10 mpaka 100 kuposa mpweya wotchinga wamba, nthawi zambiri samadziwika ndi wopanga zisindikizo zamakina, koma zimatengera kuchuluka kwa mpweya womwe pampuyo ingapirire.
Kawirikawiri, ma flowmeter osinthasintha amagwiritsidwa ntchito ndipo si zachilendo kuti ma flowmeter otsika ndi apamwamba azilumikizidwa motsatizana. Chosinthira cha flowmeter chachikulu chimatha kuyikidwa pa flowmeter yothamanga kwambiri kuti chipereke alamu yothamanga kwambiri. Ma flowmeter osinthasintha amatha kuyesedwa kokha kuti apeze mpweya wina pa kutentha ndi kupsinjika kwina. Mukagwira ntchito pansi pa mikhalidwe ina, monga kusinthasintha kwa kutentha pakati pa chilimwe ndi nyengo yozizira, flowmeter yomwe ikuwonetsedwa siyingaganizidwe kuti ndi yolondola, koma ili pafupi ndi mtengo weniweni.
Ndi kutulutsidwa kwa API 682 4th edition, miyeso ya kayendedwe ka madzi ndi kuthamanga kwa madzi yasamuka kuchoka pa analog kupita pa digito yokhala ndi mawerengedwe am'deralo. Ma flowmeter a digito angagwiritsidwe ntchito ngati ma variable area flowmeters, omwe amasintha malo oyandama kukhala ma digital signals, kapena ma mass flowmeters, omwe amasintha okha mass flow kukhala volume flow. Chinthu chodziwika bwino cha ma mass flow transmitters ndichakuti amapereka zotulutsa zomwe zimakwaniritsa kupanikizika ndi kutentha kuti zipereke kayendedwe koona pansi pa mlengalenga wokhazikika. Choyipa chake ndichakuti zipangizozi ndi zodula kuposa ma variable area flowmeters.
Vuto logwiritsa ntchito chotumizira madzi ndikupeza chotumizira chomwe chingathe kuyeza kuyenda kwa mpweya wotchinga panthawi yogwira ntchito bwino komanso pamalo ochenjeza kuyenda kwa madzi ambiri. Zosensa zamadzi zimakhala ndi mitengo yayikulu komanso yocheperako yomwe ingawerengedwe molondola. Pakati pa zero flow ndi mtengo wocheperako, kutuluka kwa madzi sikungakhale kolondola. Vuto ndilakuti pamene kuchuluka kwa madzi ambiri kwa mtundu wina wa chotumizira madzi kumawonjezeka, kuchuluka kwa madzi ochepa kumawonjezekanso.
Njira imodzi yothetsera vutoli ndi kugwiritsa ntchito ma transmitter awiri (limodzi lotsika ndi lina lokwera), koma iyi ndi njira yokwera mtengo. Njira yachiwiri ndikugwiritsa ntchito sensa yoyendera madzi kuti igwire bwino ntchito ndikugwiritsa ntchito switch yoyendera madzi yokhala ndi mita yoyendera madzi yotsika kwambiri. Gawo lomaliza lomwe gasi wotchinga umadutsa ndi valavu yoyang'anira mpweya wotchinga usanachoke pagawolo ndikulumikizana ndi chisindikizo cha makina. Izi ndizofunikira kuti madzi opompedwa asabwerere m'mbuyo ndikuwonongeka kwa chipangizocho ngati pakhala kusokonezeka kwa njira yogwirira ntchito.
Vavu yofufuzira iyenera kukhala ndi mphamvu yotseguka yochepa. Ngati kusankha sikuli bwino, kapena ngati chisindikizo cha mpweya cha pampu yopondereza kawiri chili ndi mpweya woletsa wotsika, zitha kuwoneka kuti mpweya woletsa mpweya umatuluka chifukwa cha kutsegula ndi kuyikanso malo a valavu yofufuzira.
Kawirikawiri, nayitrogeni wa zomera amagwiritsidwa ntchito ngati mpweya wotchinga chifukwa umapezeka mosavuta, wopanda mphamvu ndipo suyambitsa zotsatira zoyipa za mankhwala mu madzi opompedwa. Mipweya yopanda mphamvu yomwe siilipo, monga argon, ingagwiritsidwenso ntchito. Ngati mphamvu yofunikira ya mpweya woteteza ndi yayikulu kuposa mphamvu ya nayitrogeni wa zomera, chowonjezera mphamvu chimatha kuwonjezera mphamvu ndikusunga mpweya wopanikizika kwambiri mu cholandirira cholumikizidwa ku Plan 74 panel inlet. Mabotolo a nayitrogeni a m'mabotolo nthawi zambiri sakuvomerezedwa chifukwa amafunika kusintha masilinda opanda kanthu nthawi zonse ndi odzaza. Ngati mtundu wa chisindikizo wachepa, botolo likhoza kuchotsedwa mwachangu, zomwe zimapangitsa kuti pampu iyime kuti pasawonongeke komanso kulephera kwa chisindikizo cha makina.
Mosiyana ndi makina otchingira madzi, makina othandizira a Plan 74 safuna kukhala pafupi ndi zisindikizo zamakina. Chenjezo lokhalo apa ndi gawo lalitali la chubu chaching'ono cha m'mimba mwake. Kutsika kwa mphamvu pakati pa gulu la Plan 74 ndi chisindikizo kungachitike mu chitoliro panthawi ya kuyenda kwakukulu (kuwonongeka kwa chisindikizo), zomwe zimachepetsa mphamvu yotchingira yomwe ilipo pa chisindikizo. Kuonjezera kukula kwa chitoliro kungathe kuthetsa vutoli. Nthawi zambiri, mapanelo a Plan 74 amayikidwa pa choyimilira pamalo abwino kuti azitha kuwongolera ma valve ndi kuwerenga zida zowerengera. Bulaketi ikhoza kuyikidwa pa mbale yoyambira pampu kapena pafupi ndi pampu popanda kusokoneza kuyang'anira ndi kukonza pampu. Pewani zoopsa pa mapaipi/mapaipi olumikiza mapanelo a Plan 74 ndi zisindikizo zamakina.
Pa mapampu olumikizana okhala ndi zisindikizo ziwiri zamakina, chimodzi kumapeto kwa pampu, sikoyenera kugwiritsa ntchito gulu limodzi ndikulekanitsa chotulutsira mpweya chotchinga ku chisindikizo chilichonse chamakina. Yankho lovomerezeka ndikugwiritsa ntchito gulu lina la Plan 74 pa chisindikizo chilichonse, kapena gulu la Plan 74 lokhala ndi zotulutsa ziwiri, lililonse lili ndi zida zake zoyezera madzi ndi ma switch oyendera madzi. M'madera omwe kuli nyengo yozizira, kungakhale kofunikira kuti mapampu a Plan 74 alowe m'nyengo yozizira. Izi zimachitika makamaka kuti ateteze zida zamagetsi za gululo, nthawi zambiri poika gululo mu kabati ndikuwonjezera zinthu zotenthetsera.
Chodabwitsa n'chakuti kuchuluka kwa mpweya wotchinga kumawonjezeka ndi kuchepa kwa kutentha kwa mpweya wotchinga. Izi nthawi zambiri sizimawonedwa, koma zimatha kuonekera m'malo omwe nyengo yozizira imakhala yozizira kapena kusiyana kwakukulu kwa kutentha pakati pa chilimwe ndi nyengo yozizira. Nthawi zina, kungakhale kofunikira kusintha malo oti alamu iyende bwino kuti mupewe ma alarm abodza. Ma duct a mpweya ndi mapaipi olumikizira ayenera kutsukidwa musanayike mapanelo a Plan 74. Izi zimachitika mosavuta powonjezera valavu yotulukira mpweya pafupi ndi kapena pafupi ndi cholumikizira cha makina. Ngati valavu yotuluka magazi palibe, makinawo akhoza kutsukidwa mwa kuchotsa chubu/chubu kuchokera ku chisindikizo cha makina kenako n’kuchilumikizanso mutachotsa.
Pambuyo polumikiza mapanelo a Plan 74 ku zisindikizo ndikuwona ngati pali kutayikira kulikonse, chowongolera kuthamanga tsopano chikhoza kusinthidwa kuti chigwirizane ndi kuthamanga komwe kwayikidwa mu pulogalamuyo. Panelo liyenera kupereka mpweya woletsa kupanikizika ku chisindikizo cha makina musanadzaze pampu ndi madzi oyendetsera ntchito. Zisindikizo ndi mapanelo a Plan 74 amakhala okonzeka kuyamba pamene njira zoyankhira ndi kutulutsa mpweya pampu zatha.
Chinthu choseferacho chiyenera kuyang'aniridwa patatha mwezi umodzi chikugwira ntchito kapena miyezi isanu ndi umodzi iliyonse ngati palibe kuipitsidwa komwe kwapezeka. Nthawi yosinthira fyuluta idzadalira kuyera kwa mpweya woperekedwa, koma sayenera kupitirira zaka zitatu.
Kuchuluka kwa mpweya woletsa mpweya kuyenera kufufuzidwa ndikulembedwa panthawi yowunikira nthawi zonse. Ngati mpweya woletsa mpweya womwe umatuluka chifukwa cha kutseguka ndi kutsekedwa kwa valavu yoyezera ndi waukulu mokwanira kuyambitsa alamu yothamanga kwambiri, ma alamu awa angafunike kuwonjezeredwa kuti apewe ma alamu abodza.
Gawo lofunika kwambiri pakuchotsa ntchito ndikuti kulekanitsa ndi kuchepetsa mphamvu ya mpweya woteteza mpweya kuyenera kukhala gawo lomaliza. Choyamba, lekanitsa ndi kuchepetsa mphamvu ya mpweya woteteza mpweya. Pampu ikangokhala bwino, mphamvu ya mpweya woteteza mpweya ikhoza kuzimitsidwa ndipo mphamvu ya mpweya woteteza mpweya ichotsedwe paipi yolumikiza gulu la Plan 74 ku chisindikizo cha makina. Tulutsani madzi onse mu dongosolo musanayambe ntchito iliyonse yokonza.
Zisindikizo za mpweya zopopera mpweya ziwiri pamodzi ndi makina othandizira a Plan 74 zimapatsa ogwiritsa ntchito njira yothetsera vuto la kutseka kwa shaft yopanda mpweya, ndalama zochepa zogulira (poyerekeza ndi zisindikizo zomwe zili ndi makina otchingira madzi), ndalama zochepa zogulira moyo, malo ochepa othandizira komanso zofunikira zochepa pa ntchito.
Ikayikidwa ndikugwiritsidwa ntchito motsatira njira zabwino kwambiri, njira yotetezera iyi ingapereke kudalirika kwa nthawi yayitali ndikuwonjezera kupezeka kwa zida zozungulira.
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Mark Savage ndi manejala wa gulu la zinthu ku John Crane. Savage ali ndi digiri ya Bachelor of Science mu Engineering kuchokera ku University of Sydney, Australia. Kuti mudziwe zambiri pitani ku johncrane.com.
Nthawi yotumizira: Sep-08-2022