Uma uhambahamba endaweni yokusebenzela yamakhemikhali, uzobona amapayipi athile afakwe amavalvu anezinhloko eziyindilinga, okuyiwona alawula amavalvu.
I-valve yokulawula i-diaphragm yomoya
Ungathola ulwazi oluthile mayelana ne-valve yokulawula kusuka egameni layo. Igama eliyisihluthulelo elithi “umthethonqubo” ukuthi ububanzi bayo bokulungisa bungalungiswa ngokungenanjongo phakathi kuka-0 no-100%.
Abangani abaqaphile kufanele bathole ukuthi kukhona idivayisi elenga ngaphansi kwekhanda levalvu ngayinye elawulayo. Labo abajwayelene nayo kumele bazi ukuthi lena yinhliziyo yevalvu elawulayo, indawo yokufaka ivalvu. Ngale divayisi, ivolumu yomoya engena ekhanda (ifilimu yomoya) ingalungiswa. Lawula ngokunembile indawo yevalvu.
Ama-valve positioners afaka phakathi ama-positioners ahlakaniphile kanye nama-mechanical positioners. Namuhla sixoxa nge-mechanical positioner yokugcina, efana ne-positioner eboniswe esithombeni.
Isimiso sokusebenza se-mechanical pneumatic valve positioner
Umdwebo wesakhiwo se-valve positioner
Isithombe sichaza ngokuyisisekelo izingxenye ze-mechanical pneumatic valve positioner ngayinye ngayinye. Isinyathelo esilandelayo ukubona ukuthi isebenza kanjani?
Umthombo womoya uvela emoyeni ocindezelwe wesiteshi se-air compressor. Kukhona i-valve yokunciphisa umfutho wesihlungi somoya phambi kokungena komthombo womoya we-valve positioner ukuze kuhlanzwe umoya ocindezelwe. Umthombo womoya ovela endaweni yokukhipha i-valve yokunciphisa umfutho ungena kusuka endaweni yokubeka i-valve. Inani lomoya ongena ekhanda le-membrane ye-valve linqunywa ngokuya ngesignali yokukhipha yomlawuli.
Ukukhishwa kwesignali kagesi yisilawuli kungu-4~20mA, kanti isignali yomoya ingu-20Kpa~100Kpa. Ukuguqulwa kusuka esignalini kagesi kuya esignalini yomoya kwenziwa ngesiguquli sikagesi.
Uma ukuphuma kwesignali kagesi yisilawuli kuguqulwa kube yisignali yegesi ehambisanayo, isignali yegesi eguquliwe ibe isisebenza ezimbotsheni. I-Lever 2 ihamba izungeze i-fulcrum, bese ingxenye engezansi ye-lever 2 ihambela ngakwesokudla bese isondela embotsheni. Ingcindezi yangemuva ye-nozzle iyanda, futhi ngemva kokukhuliswa yi-amplifier ye-pneumatic (ingxenye enophawu olungaphansi kwesithombe), ingxenye yomthombo womoya ithunyelwa ekamelweni lomoya le-diaphragm ye-pneumatic. Isiqu se-valve sithwala umongo we-valve phansi bese sivula i-valve ngokuzenzakalelayo. iba ncane kancane. Ngalesi sikhathi, induku yempendulo (induku ye-swing esithombeni) exhunywe embotsheni ye-valve ihamba phansi izungeze i-fulcrum, okwenza ukuthi ingxenye engaphambili ye-shaft iye phansi. I-cam eccentric exhunywe kuyo ijikeleza ngokuphambene newashi, kanti i-roller ijikeleza ngokwewashi bese ihamba ngakwesobunxele. Yelula intwasahlobo yempendulo. Njengoba ingxenye engezansi yentwasahlobo yempendulo yelula i-lever 2 futhi ihambela ngakwesobunxele, izofinyelela ibhalansi yamandla ngokucindezela kwesignali okusebenza ezimbotsheni, ngakho-ke i-valve igxilile endaweni ethile futhi ayinyakazi.
Ngalesi singeniso esingenhla, kufanele ube nokuqonda okuthile nge-mechanical valve positioner. Uma unethuba, kungcono ukuyihlukanisa kanye ngenkathi uyisebenzisa, bese ujulisa indawo yengxenye ngayinye ye-positioner kanye negama lengxenye ngayinye. Ngakho-ke, ingxoxo emfushane yama-mechanical valve iyaphela. Okulandelayo, sizokwandisa ulwazi ukuze sithole ukuqonda okujulile kwama-valve alawulayo.
ukwanda kolwazi
Ukwandiswa kolwazi olulodwa
Ivalvu yokulawula i-diaphragm ye-pneumatic esithombeni iwuhlobo oluvaliwe ngomoya. Abanye abantu bayabuza, kungani?
Okokuqala, bheka indlela yokungena komoya ye-aerodynamic diaphragm, okuwumphumela omuhle.
Okwesibili, bheka indlela yokufaka i-valve core, okuyinto enhle.
Umthombo womoya wegumbi lomoya le-diaphragm, i-diaphragm icindezela phansi iziphethu eziyisithupha ezimbozwe yi-diaphragm, ngaleyo ndlela icindezela isiqu se-valve ukuthi siye phansi. Isiqu se-valve sixhunywe enkabeni ye-valve, futhi i-valve core ifakwe phambili, ngakho umthombo womoya yi-valve Hamba uye endaweni yokuvala. Ngakho-ke, ibizwa ngokuthi i-air-to-close valve. Ukuvula iphutha kusho ukuthi lapho ukunikezwa komoya kuphazamiseka ngenxa yokwakhiwa noma ukugqwala kwepayipi lomoya, i-valve isethwa kabusha ngaphansi kwamandla okusabela entwasahlobo, futhi i-valve isuke isesimweni esivulekile ngokuphelele futhi.
Ungayisebenzisa kanjani i-valve yokuvala umoya?
Indlela yokuyisebenzisa ibhekwa ngokombono wokuphepha. Lesi yisimo esidingekayo ekukhetheni ukuthi uzovula noma uvale umoya.
Isibonelo: idrama lomusi, enye yezinto eziyinhloko zebhoyila, kanye nevalvu yokulawula esetshenziswa ohlelweni lokuphakelwa kwamanzi kumele zivalwe ngomoya. Kungani? Isibonelo, uma umthombo wegesi noma ugesi uphazamiseka ngokuzumayo, isithando sisavutha ngamandla futhi sifudumeza amanzi njalo esigubheni. Uma igesi isetshenziselwa ukuvula ivalvu yokulawula futhi amandla ephazamiseka, ivalvu lizovalwa futhi isigubhu sizoshiswa ngemizuzu embalwa ngaphandle kwamanzi (ukusha okomile). Lokhu kuyingozi kakhulu. Akunakwenzeka ukubhekana nokuhluleka kwevalvu yokulawula ngesikhathi esifushane, okuzoholela ekuvalweni kwesithando. Kwenzeka izingozi. Ngakho-ke, ukuze kugwenywe ukusha okomile noma ngisho nezingozi zokusha komlilo, kumele kusetshenziswe ivalvu yokuvala igesi. Nakuba amandla ephazamiseka futhi ivalvu yokulawula isendaweni evulekile ngokuphelele, amanzi aqhubeka efakwa esigubheni somusi, kodwa ngeke kubangele imali eyomile esigubheni somusi. Kusenesikhathi sokubhekana nokuhluleka kwevalvu yokulawula futhi isithando ngeke sicinywe ngqo ukuze sibhekane naso.
Ngezibonelo ezingenhla, kufanele manje ube nokuqonda kokuqala kokuthi ungakhetha kanjani amavalvu okulawula okuvula umoya kanye namavalvu okulawula okuvala umoya!
Ukwandiswa Kolwazi 2
Lolu lwazi oluncane lumayelana nezinguquko emiphumeleni emihle nemibi yesitholi.
I-valve elawulayo esithombeni isebenza kahle. I-cam eccentric inezinhlangothi ezimbili u-AB, u-A umele uhlangothi olungaphambili kanti u-B umele uhlangothi. Ngalesi sikhathi, uhlangothi u-A lubheke ngaphandle, futhi ukuphendula uhlangothi u-B ngaphandle kuyisenzo. Ngakho-ke, ukushintsha isiqondiso u-A esithombeni siye ohlangothini u-B kuyisimo se-valve mechanical yokusabela.
Isithombe sangempela esithombeni siyi-valve positioner esebenza kahle, kanti isignali yokukhipha isilawuli ingu-4-20mA. Uma ingu-4mA, isignali yomoya ehambisanayo ingu-20Kpa, kanti ivalvu elawulayo ivulekile ngokuphelele. Uma ingu-20mA, isignali yomoya ehambisanayo ingu-100Kpa, kanti ivalvu elawulayo ivaliwe ngokuphelele.
Ama-valve positioners omshini anezinzuzo kanye nokungalungi
Izinzuzo: ukulawula okunembile.
Okubi: Ngenxa yokulawula komoya, uma isignali yesikhundla izobuyiselwa egumbini lokulawula eliphakathi, kudingeka idivayisi eyengeziwe yokuguqula ugesi.
Ukwandiswa kolwazi lwesithathu
Izindaba ezihlobene nokuphazamiseka kwansuku zonke.
Ukwehluleka ngesikhathi senqubo yokukhiqiza kuyinto evamile futhi kuyingxenye yenqubo yokukhiqiza. Kodwa ukuze kulondolozwe ikhwalithi, ukuphepha, kanye nobuningi, izinkinga kumele zixazululwe ngesikhathi. Lokhu ukubaluleka kokuhlala enkampanini. Ngakho-ke, sizoxoxa kafushane ngezimo eziningana zamaphutha ezihlangatshezwane nazo:
1. Umphumela we-valve positioner ufana nofudu.
Ungavuli isembozo sangaphambili se-valve positioner; lalela umsindo ukuze ubone ukuthi ipayipi lomthombo womoya liqhekekile yini futhi libangela ukuvuza. Lokhu kungahlulelwa ngeso lenyama. Futhi lalela ukuthi kukhona yini umsindo wokuvuza ovela egumbini lomoya elifakiwe.
Vula isembozo sangaphambili se-valve positioner; 1. Ukuthi i-orifice engaguquki ivinjiwe yini; 2. Hlola indawo ye-baffle; 3. Hlola ukuqina kwentwasahlobo yempendulo; 4. Hlukanisa i-valve yesikwele bese uhlola i-diaphragm.
2. Umphumela we-valve positioner uyadina
1. Hlola ukuthi ingcindezi yomthombo womoya ingaphakathi kwebanga elibekiwe nokuthi induku yokuphendula iwile yini. Lesi yisinyathelo esilula kakhulu.
2. Hlola ukuthi izintambo zomugqa wesignali zilungile yini (izinkinga eziphakama kamuva ngokuvamile azinakwa)
3. Ingabe kukhona okubambeke phakathi kwekhoyili kanye ne-armature?
4. Hlola ukuthi indawo efanayo ye-nozzle kanye ne-baffle iyafaneleka yini.
5. Hlola isimo sekhoyili yengxenye ye-electromagnetic
6. Hlola ukuthi indawo yokulungisa yentwasahlobo yebhalansi iyafaneleka yini
Bese kuba khona isignali efakwayo, kodwa ingcindezi yokukhipha ayishintshi, kukhona okukhiphayo kodwa akufinyeleli inani eliphezulu, njll. La maphutha atholakala futhi emaphutheni ansuku zonke futhi ngeke kuxoxwe ngawo lapha.
Ukwandiswa kolwazi lwesine
Ukulawula ukulungiswa kwe-valve stroke
Ngesikhathi senqubo yokukhiqiza, ukusebenzisa i-valve yokulawula isikhathi eside kuzoholela ekushayweni okungafanele. Ngokuvamile, kuhlale kunephutha elikhulu lapho uzama ukuvula indawo ethile.
I-stroke ingu-0-100%, khetha iphuzu eliphakeme kakhulu lokulungisa, okungu-0, 25, 50, 75, kanye no-100, konke kuvezwa njengamaphesenti. Ikakhulukazi kuma-valve positioners omshini, lapho ulungisa, kubalulekile ukwazi izindawo zezingxenye ezimbili zesandla ngaphakathi kwe-positioner, okungukuthi indawo yokulungisa engu-zero kanye ne-adjustment span.
Uma sithatha ivalvu elawula ukuvulwa komoya njengesibonelo, yilungise.
Isinyathelo 1: Endaweni yokulungisa engu-zero, igumbi lokulawula noma ijeneretha yesignali inikeza i-4mA. Ivalvu yokulawula kufanele ivalwe ngokuphelele. Uma ingakwazi ukuvalwa ngokuphelele, yenza ukulungiswa okungu-zero. Ngemva kokulungiswa okungu-zero sekuqediwe, lungisa ngqo iphuzu elingu-50%, bese ulungisa ububanzi ngokufanele. Ngesikhathi esifanayo, qaphela ukuthi induku yokuphendula kanye nesiqu sevalvu kufanele kube sesimweni esiqondile. Ngemva kokulungiswa sekuqediwe, lungisa iphuzu elingu-100%. Ngemva kokulungiswa sekuqediwe, lungisa ngokuphindaphindiwe kusukela kumaphuzu amahlanu phakathi kuka-0-100% kuze kube yilapho ukuvulwa kunembile.
Isiphetho; kusukela ku-mechanical positioner kuya ku-intelligence positioner. Ngokombono wesayensi nobuchwepheshe, intuthuko esheshayo yesayensi nobuchwepheshe inciphise amandla abasebenzi abasebenza phambili. Mina ngokwami, ngicabanga ukuthi uma ufuna ukusebenzisa amakhono akho okusebenza ngezandla nokufunda amakhono, i-mechanical positioner iyona engcono kakhulu, ikakhulukazi kubasebenzi abasha bezinsimbi zomculo. Ukubeka ngokusobala, i-intelligence locator ingaqonda amagama ambalwa encwadini bese inyakazisa iminwe yakho. Izolungisa ngokuzenzakalelayo yonke into kusukela ekulungiseni iphuzu elingu-zero kuya ekulungiseni ububanzi. Vele ulinde ukuthi iqede ukudlala bese uhlanza indawo. Vele uhambe. Ngohlobo lwe-mechanical, izingxenye eziningi zidinga ukuhlukaniswa, ukulungiswa nokufakwa kabusha nguwe. Lokhu kuzothuthukisa ikhono lakho lokusebenza ngezandla futhi kukwenze uhlabeke umxhwele kakhulu ngesakhiwo sangaphakathi salo.
Kungakhathaliseki ukuthi ihlakaniphile noma ayihlakaniphile, idlala indima evelele kuyo yonke inqubo yokukhiqiza ezenzakalelayo. Uma “ishaya”, ayikho indlela yokulungisa futhi ukulawula okuzenzakalelayo akusizi ngalutho.
Isikhathi sokuthunyelwe: Agasti-31-2023