Mu dziko la kulamulira madzi, komwe kulondola ndi kudalirika ndizofunikira kwambiri, mpando wa valavu ndiye ngwazi yosayamikirika. Gawo lofunika kwambiri ili ndiye maziko a magwiridwe antchito a valavu, zomwe zimakhudza mwachindunji umphumphu wake wosatulutsa madzi, moyo wake wautumiki, komanso chitetezo chonse. Kaya ndinu mainjiniya, katswiri wokonza, kapena katswiri wogula, kumvetsetsa bwino zaMpando wa Vavundikofunikira kwambiri kuti dongosolo ligwire bwino ntchito.
Kodi Mpando wa Valuvu ndi Chiyani?
Mpando wa valavu ndi gawo lofunika kwambiri la mkati mwa valavu lomwe limapanga theka la awiri otsekera. Ndi malo osasuntha omwe chinthu chotseka cha valavu—monga mpando wa valavu ya mpira chimalumikizana ndi mpira, kapena mpando wa valavu yozungulira ndi pulagi—zimalumikizana kuti madzi asamayende bwino.
Taganizirani izi ngati "mpando" wokonzedwa bwino wa gawo loyenda. Pamene valavu yatsekedwa, chinthu chotsekacho chimakhala cholimba motsutsana ndi mpando wa valavu, ndikupanga chisindikizo chomwe chimalekanitsa mbali yakumtunda ndi mbali yakumunsi. Ubwino wa mawonekedwe awa umadalira kalasi ya kutayikira kwa valavu ndi kuthekera kwake kunyamula kupanikizika.
Ntchito Zofunika Kwambiri za Mpando wa Valavu
Mpando wa valavu ndi gawo la anthu aluso ambiri, kuchita ntchito zingapo zofunika:
1. Kusindikiza Koyamba:Cholinga chake chachikulu ndikupanga chisindikizo cholimba chomwe chimatseka ndi chinthu chotseka, kuti madzi asadutse pamene valavu ili pamalo otsekedwa.
2. Kuthandizira Chotsekera:Mpando wa valavu uli ndi mphamvu yogwiritsidwa ntchito ndi chinthu chotseka ndi kupanikizika kwa dongosolo, zomwe zimapereka chithandizo chokhazikika pamene valavu yatsekedwa.
3. Chitsogozo ndi Kulinganiza:Mu mitundu ina ya ma valve monga Globe Valve Seats, mpando nthawi zambiri umathandizira kutsogolera pulagi kapena disc, kuonetsetsa kuti chisindikizocho chikugwirizana bwino komanso nthawi zonse chikugwirizana.
4. Gawo Lofunika la Malire Opanikizika:Mpando ndi chinthu chofunikira kwambiri pa thupi la valavu lomwe lili ndi kupanikizika, chomwe chimafuna mphamvu zambiri komanso kukhazikika, makamaka pakugwiritsa ntchito kupanikizika kwambiri.
Zipangizo za Mpando wa Valavu: Kusankha Choyenera
Kusankha zipangizo zoyenera zotetezera valavu ndi njira yolumikizirana pakati pa kugwirizana kwa mankhwala, kutentha, kupanikizika, kukana kuwonongeka, ndi mtengo. Kusankha kumeneku kumatanthauza mtundu wa valavu yomwe ingagwiritsidwe ntchito.
Mipando Yofewa (Polymeric):
• PTFE (Teflon):Imapereka kukana kwapadera kwa mankhwala, kusinthasintha kochepa kwambiri, komanso kutentha kwakukulu. Ndi chisankho chabwino kwambiri pa ntchito zowononga ndi mapulogalamu omwe amafuna kutsekedwa kolimba ngati thovu.
• NBR (Rabala ya Nitrile):Amapereka kukana bwino mafuta ndi mafuta, zomwe zimapangitsa kuti azigwiritsidwa ntchito kwambiri mu mafuta, madzi, ndi mpweya.
• EPDM (Ethylene Propylene Diene Monomer):Amadziwika ndi nyengo yabwino, ozone, komanso kukana nthunzi, abwino kwambiri pamadzi otentha, makina ozizira, ndi mankhwala osiyanasiyana.
•Zisindikizo za Silikoni:Zimapereka kukana kutentha, mankhwala, ndi kukula kwa tizilombo toyambitsa matenda. Zimagwiritsidwa ntchito kwambiri poyambira -100°C mpaka +316°C (-148°F mpaka +600°F)
Mipando yachitsulo:
• Chitsulo Chosapanga Dzira (304, 316):Njira yogwiritsira ntchito madzi, nthunzi, mafuta, ndi mankhwala ambiri, yosawononga dzimbiri.
• Chitsulo cha Aloyi (13Cr, 17-4PH):Amagwiritsidwa ntchito polimbitsa mphamvu ndi kuuma m'malo omwe muli mpweya woipa komanso kutentha kwambiri.
• Chitsulo Chosapanga Dzimbiri:Zimaphatikiza mphamvu zambiri ndi kukana dzimbiri kwambiri, makamaka motsutsana ndi kusweka kwa dzimbiri komwe kumabwera chifukwa cha chloride.
• Ma Alloys Apadera (Monel, Hastelloy):Amagwiritsidwa ntchito pa ntchito zowononga kwambiri, monga madzi a m'nyanja, hydrofluoric acid, kapena hot sulfuric acid.
• Ma Alloy Ochokera ku Cobalt (Stellite):Imayikidwa ngati chinthu cholimba pamwamba pa mpando kuti ipereke kuwononga kwambiri komanso kukana kukokoloka kwa nthaka.
Kugwirizana Koyamba:Mipando yofewa nthawi zambiri imakhala ndi chitseko cholimba ngati thovu koma imakhala ndi malire ochepa a kutentha ndi kupanikizika. Mipando yachitsulo imatha kupirira malo ovuta, otentha/kupanikizika kwambiri koma kupeza malo osatulutsa madzi kungakhale kovuta kwambiri.
Malire a Kutentha kwa Mpando wa Valavu
Mphamvu ya mpando yopirira kutentha imatengera zinthu zomwe uli nazo.
•Mipando Yofewa:Kawirikawiri amagwira ntchito mkati mwa gulu lotentha pang'ono. EPDM nthawi zambiri imakhala ndi malire a ~150°C, NBR mpaka ~80°C, pomwe PTFE imatha kugwira ntchito mpaka ~260°C. Kupitilira izi, ma polima amawonongeka, amalimba, kapena amawonongeka kwamuyaya, zomwe zimapangitsa kuti chisindikizo chilephereke.
•Mipando yachitsulo:Zapangidwa kuti zigwiritsidwe ntchito kutentha kwambiri, zomwe zimatha kugwira ntchito kuyambira kutentha kwa cryogenic mpaka kupitirira 800°C, kutengera ndi alloy. Zipangizozo ziyenera kusunga mphamvu zake ndikukana okosijeni ndi kugwedezeka pazovuta izi.
Mavoti a Kupanikizika kwa Mpando wa Valavu
Mpando wa valavu uyenera kupirira momwe makinawo amagwirira ntchito popanda kusokonekera kapena kulephera.
• Machitidwe Otsika Pakupanikizika: Mipando yofewa komanso yachitsulo yokhazikika ndiyoyenera.
• Machitidwe Opanikizika Pakati Pang'ono Mpaka Pamwamba: Amafuna mipando yachitsulo yolimba. Kapangidwe kake, monga kugwiritsa ntchito mipando yakumbuyo kapena nyumba zolimbitsa, kumakhala kofunikira kwambiri kuti mipando isawonongeke.
• Machitidwe Opanikizika Kwambiri: Kufuna mipando yachitsulo yopangidwa mwapadera, nthawi zambiri yochokera ku zitsulo zolimba kwambiri, yokhala ndi zomaliza zolondola kwambiri pamwamba kuti tipewe kuti zinthu zobisika zisalowe m'malo ofooka a pamwamba.
Ndikofunikira kukumbukira kuti kutentha ndi kupanikizika zimadalirana; kutentha kwambiri kumachepetsa mphamvu ya chinthu.
Kapangidwe ka Mpando wa Vavu Pamitundu Yosiyanasiyana ya Vavu
Kapangidwe ndi kagwiritsidwe ntchito ka mpando wa valavu zimasiyana kwambiri kutengera mtundu wa valavu. Nayi njira zina zodziwika bwino zokonzera.
Mpando wa Valavu ya Mpira
TheMpando wa Valavu ya Mpirandi diski yooneka ngati mphete, nthawi zambiri imakhala iwiri, yomwe imakhala m'thupi la valavu mbali zonse ziwiri za mpira.
• Kapangidwe: Nthawi zambiri “koyandama,” komwe mphamvu ya dongosolo kapena mphamvu ya kasupe imakankhira mpando motsutsana ndi mpira kuti upange chisindikizo. Kapangidwe kameneka kangapereke chisindikizo cha mbali ziwiri kapena chimodzi.
•Njira Yotsekera: Mipando yofewa ndi yachitsulo imagwiritsidwa ntchito kwambiri. Pamapangidwe oteteza moto, mpando wofewa umayaka pamoto, zomwe zimapangitsa kuti chisindikizo chachiwiri chachitsulo ndi chachitsulo chikhale pakati pa mpira ndi mpando wachiwiri.
Mpando wa Valavu wa Globe
Mpando wa Globe Valve nthawi zambiri umakhala ngati mphete yosasuntha, yolumikizidwa m'thupi la valavu, pomwe pulagi kapena diski imatsekedwa.
•Kapangidwe: Mpando nthawi zambiri umakhala mphete yosiyana, yongowonjezedwanso yomwe imalumikizidwa, kukanikiza, kapena kulowetsedwa m'thupi la valavu. Izi zimathandiza kuti kukonza ndi kusintha zikhale zosavuta.
•Njira Yotsekera: Nthawi zambiri zimakhala ndi pulagi yosalala kapena yozungulira yokhala ndi mpando wofanana. Kuphatikiza kwa zipangizo kumatha kukhala kuyambira zitsulo zofewa mpaka zolimba, zomwe zimapereka mphamvu zabwino kwambiri zotsekera ndi kutseka.
Mpando wa Valuti wa Gulugufe
AMpando wa Valuti wa Gulugufendi mphete yozungulira yopitilira yomwe imazungulira m'mimba mwake wamkati mwa thupi la valavu.
•Kapangidwe: Disiki imazungulira kotala la mpando uwu. Mpandowo ukhoza kukhala mphete yokanikizidwa, yolumikizidwa (yovunda) ku thupi, kapena kapangidwe kosungidwa bwino, kosinthika.
•Njira Yotsekera: Mipando yofewa (EPDM, PTFE) ndi yofala kwambiri, pomwe malire a diski amakakamira pampando wolimba. Ma valve a gulugufe okhala ndi zitsulo amagwiritsa ntchito malo ovuta olumikizirana kuti azimitse mwamphamvu pa ntchito zotentha kwambiri.
Mapangidwe Ena Ofunika a Mpando wa Valve
•Mpando Woyang'anira Valavu: Imagwira ntchito mofanana ndi mpando wa valavu yozungulira, yopangidwira kugwira ntchito yokha. Disiki (kapena wafer) imatseka mpando kuti isabwerere m'mbuyo, zomwe zimafuna yankho lachangu komanso kutseka mwamphamvu.
•Mpando wa Valavu ya Chipata: Nthawi zambiri imakhala ndi mphete ziwiri zofanana, zosasuntha m'thupi la valavu. Chipatacho chimagawikana pakati pawo. Mipando nthawi zambiri imakhala yofunika kwambiri pa thupi kapena yolumikizidwa kuti ikhale yolimba mu ntchito zodzipatula zamphamvu.
•Mpando wa Valavu ya Pulagi: Mu valavu yolumikizidwa ndi mafuta, kutseka kumachitika poika chosindikizira pakati pa pulagi ndi thupi. Mu mtundu wosalumikizidwa ndi mafuta, chikwama chopangidwa ndi PTFE kapena zinthu zofanana chimagwira ntchito ngati mpando wa valavu wolimba.
Mapeto
Kuyambira pa mpope wamba mpaka mafakitale ovuta m'mafakitale opanga mankhwala, magetsi, ndi ndege, mpando wa valavu ndi mwala wapangodya wa dongosolo lowongolera madzi. Mwa kuganizira mosamala za zipangizo zake, kapangidwe kake, ndi malire ake ogwirira ntchito, mutha kuwonetsetsa kuti makina anu ogwiritsira ntchito madzi ndi otetezeka, ogwira ntchito bwino, komanso okhalitsa.
Nthawi yotumizira: Okutobala-29-2025