Vavu yoyimitsa imagwiritsidwa ntchito makamaka poyendetsa ndikuletsa madzi kuyenda kudzera mu payipi. Amasiyana ndi mavavu mongamavavu a mpirandi ma valve a chipata chifukwa amapangidwira kuti azilamulira kuyenda kwa madzi ndipo samangokhala pa ntchito zotseka. Chifukwa chomwe valavu yoyimitsa imatchulidwira chonchi ndichakuti kapangidwe kakale kamakhala ndi thupi linalake lozungulira ndipo kangagawidwe m'magawo awiri, olekanitsidwa ndi equator, komwe kuyenda kumasintha njira. Zinthu zenizeni zamkati mwa mpando wotseka nthawi zambiri sizikhala zozungulira (monga ma valve a mpira) koma nthawi zambiri zimakhala zozungulira, zozungulira, kapena zooneka ngati pulagi. Ma valve a globe amaletsa kuyenda kwa madzi kwambiri akamatsegulidwa kuposa ma valve a chipata kapena mpira, zomwe zimapangitsa kuti kuthamanga kwamphamvu kudutse mwa iwo. Ma valve a globe ali ndi mawonekedwe atatu akuluakulu a thupi, ena mwa iwo amagwiritsidwa ntchito kuchepetsa kutsika kwa kuthamanga kudzera mu valavu. Kuti mudziwe zambiri za ma valve ena, chonde onani Buku lathu la ogula ma valve.

Kapangidwe ka valavu

Valavu yoyimitsa imapangidwa ndi zigawo zitatu zazikulu: thupi la valavu ndi mpando, diski ya valavu ndi tsinde, kulongedza ndi bonnet. Pakugwira ntchito, tembenuzani tsinde lolumikizidwa kudzera mu gudumu lamanja kapena choyendetsera valavu kuti mukweze diski ya valavu kuchokera pampando wa valavu. Njira yamadzimadzi kudzera mu valavu ili ndi njira yooneka ngati Z kotero kuti madzimadzi amatha kukhudza mutu wa diski ya valavu. Izi ndizosiyana ndi mavalavu a chipata komwe madzimadzi amakhala olunjika ku chipata. Kapangidwe kameneka nthawi zina kamafotokozedwa ngati thupi la valavu looneka ngati Z kapena valavu yooneka ngati T. Cholowera ndi chotulukira zimagwirizana.

Mapangidwe ena amaphatikizapo ma angles ndi mapatani ooneka ngati Y. Mu valavu yoyimitsa ngodya, malo otulukira mpweya ali pa 90 ° kuchokera ku malo olowera mpweya, ndipo madziwo amayenda motsatira njira yooneka ngati L. Mu kapangidwe ka thupi la valavu yooneka ngati Y kapena Y, tsinde la valavu limalowa m'thupi la valavu pa 45 °, pomwe malo olowera mpweya ndi malo otulukira mpweya amakhalabe pamzere, mofanana ndi mu njira ya njira zitatu. Kukana kwa pateni ya angular kuti iyende bwino ndi kochepa kuposa kwa pateni yooneka ngati T, ndipo kukana kwa pateni yooneka ngati Y ndi kochepa. Ma valve atatu ndi omwe amapezeka kwambiri mwa mitundu itatuyi.

Chidebe chotsekera nthawi zambiri chimakhala chopindika kuti chigwirizane ndi mpando wa valavu, koma chidebe chosalala chingagwiritsidwenso ntchito. Vavu ikatsegulidwa pang'ono, madziwo amayenderera mofanana mozungulira chidebecho, komanso kufalikira kwa valavu pampando ndi chidebecho. Chifukwa chake, valavu imagwira ntchito bwino pamene madzi akuyenda pang'onopang'ono. Nthawi zambiri, njira yoyendera imakhala mbali ya tsinde la valavu, koma pamalo otentha kwambiri (nthunzi), pamene thupi la valavu lizizira ndikuchepa, madziwo nthawi zambiri amabwerera m'mbuyo kuti valavu isunge chidebecho chotsekedwa bwino. Vavu imatha kusintha njira yoyendera kuti igwiritse ntchito kupanikizika kuti ithandize kutseka (kuyenda pamwamba pa diski) kapena kutseguka (kuyenda pansi pa diski), motero kulola valavu kutseka kapena kulephera kutseguka.

Chida chotsekera kapena pulagi nthawi zambiri chimatsogozedwa pansi kupita ku mpando wa valavu kudzera mu khola kuti zitsimikizire kuti zikugwirizana bwino, makamaka pakugwiritsa ntchito mphamvu zambiri. Mapangidwe ena amagwiritsa ntchito mpando wa valavu, ndipo chidindo chomwe chili mbali ya ndodo ya valavu ya diski chimakanikizana ndi mpando wa valavu kuti chitulutse mphamvu pa cholongedzacho valavu ikatsegulidwa kwathunthu.

Malinga ndi kapangidwe ka chinthu chotsekera, valavu yoyimitsa imatha kutsegulidwa mwachangu potembenuza kangapo tsinde la valavu kuti iyambe kuyenda mwachangu (kapena kutsekedwa kuti imise kuyenda), kapena kutsegulidwa pang'onopang'ono ndi kuzungulira kangapo kwa tsinde la valavu kuti ipange kuyenda koyenera kudzera mu valavu. Ngakhale kuti mapulagi nthawi zina amagwiritsidwa ntchito ngati zinthu zotsekera, sayenera kusokonezedwa ndi mavalavu a pulagi, omwe ndi zida zozungulira kotala, zofanana ndi mavalavu a mpira, omwe amagwiritsa ntchito mapulagi m'malo mwa mipira kuti ayimitse ndikuyamba kuyenda.

ntchito

Ma valve oletsaamagwiritsidwa ntchito potseka ndikuwongolera malo oyeretsera madzi otayira, malo opangira magetsi ndi malo opangira zinthu. Amagwiritsidwa ntchito m'mapaipi a nthunzi, ma coolant circuits, makina odzola, ndi zina zotero, momwe kuwongolera kuchuluka kwa madzi omwe amadutsa m'ma valves kumachita gawo lofunika kwambiri.

Kusankha zinthu zomwe zili m'thupi la valavu ya padziko lonse nthawi zambiri kumakhala chitsulo chopangidwa kapena mkuwa / bronze pogwiritsa ntchito mphamvu zochepa, ndipo chitsulo cha kaboni chopangidwa kapena chitsulo chosapanga dzimbiri chogwiritsidwa ntchito ndi mphamvu zambiri komanso kutentha kwambiri. Zinthu zomwe zafotokozedwa m'thupi la valavu nthawi zambiri zimakhala ndi ziwalo zonse zopanikizika, ndipo "trim" imatanthauza zigawo zina kupatula thupi la valavu, kuphatikizapo mpando wa valavu, diski ndi tsinde. Kukula kwakukulu kumatsimikiziridwa ndi gulu la ASME class pressure, ndipo mabolts wamba kapena ma welding flanges amalamulidwa. Kukula kwa mavalavu a padziko lonse kumafuna khama lalikulu kuposa kukula kwa mitundu ina ya mavalavu chifukwa kutsika kwa mphamvu kudutsa valavu kungakhale vuto.

Kapangidwe ka tsinde lokwera ndi komwe kamapezeka kwambirima valve oletsa, koma ma valve osakwera amatha kupezekanso. Boneti nthawi zambiri imamangidwa ndipo imatha kuchotsedwa mosavuta mukamayang'ana mkati mwa valavu. Mpando wa valavu ndi diski ndizosavuta kusintha.

Ma valve oletsa nthawi zambiri amapangidwa okha pogwiritsa ntchito piston ya pneumatic kapena diaphragm actuators, zomwe zimagwira ntchito mwachindunji pa tsinde la valve kuti zisunthe disc pamalo ake. Piston / diaphragm imatha kuyikidwa m'malo mwa kasupe kuti itsegule kapena kutseka valve ikataya mphamvu ya mpweya. Choyendetsa magetsi chozungulira chimagwiritsidwanso ntchito.