Nakuba amavalvu epulasitiki ngezinye izikhathi abonwa njengomkhiqizo okhethekile—inketho ephezulu yalabo abenza noma abaklama imikhiqizo yamapayipi epulasitiki yezinhlelo zezimboni noma okufanele babe nezinto ezihlanzekile kakhulu endaweni—ukuthatha ukuthi la mavalvu awanawo amaningi asetshenziswayo kufushane- obonayo. Eqinisweni, ama-valve epulasitiki namuhla anezinhlobonhlobo zokusetshenziswa njengoba izinhlobo ezikhulayo zezinto kanye nabaklami abahle abadinga lezo zinto zisho izindlela eziningi zokusebenzisa la mathuluzi ahlukahlukene.
IMPAHLA YE-PLASTIC
Izinzuzo zama-valve e-thermoplastic zibanzi-ukugqwala, ukumelana namakhemikhali nokuhuzuka; izindonga ezibushelelezi zangaphakathi; isisindo esincane; kalula ukufakwa; ubude bempilo ende; kanye nezindleko eziphansi zomjikelezo wempilo. Lezi zinzuzo ziye zaholela ekwamukelweni okubanzi kwama-valve epulasitiki ekusetshenzisweni kwezentengiselwano nezimboni njengokusatshalaliswa kwamanzi, ukwelashwa kwamanzi angcolile, ukucutshungulwa kwensimbi namakhemikhali, ukudla nemithi, izitshalo zamandla, izindawo zokuhluza uwoyela nokunye.
Ama-valve epulasitiki angenziwa ngenani lezinto ezihlukahlukene ezisetshenziswa eziningana zokucupha. Amavalvu e-thermoplastic avame kakhulu enziwe nge-polyvinyl chloride (PVC), i-chlorinated polyvinyl chloride (CPVC), i-polypropylene (PP), ne-polyvinylidene fluoride (PVDF). Amavalvu e-PVC kanye ne-CPVC ajwayele ukujoyinwa ezinhlelweni zamapayipi ngokusebenzisa iziphetho zesokhethi ye-solvent, noma iziphetho ezinentambo nezine-flanged; kanti, i-PP ne-PVDF zidinga ukuhlanganiswa kwezingxenye zesistimu yamapayipi, kungaba ngobuchwepheshe bokushisa, i-butt- noma i-electro-fusion.
Amavalvu e-Thermoplastic ahamba phambili endaweni ebolayo, kodwa awusizo ngendlela efanayo kusevisi yamanzi evamile ngoba awanawo umthofu1, amelana nokubola futhi ngeke agqwale. Amasistimu namavalvu amapayipi e-PVC kanye ne-CPVC kufanele ahlolwe futhi anikezwe isitifiketi ku-NSF [National Sanitation Foundation] standard 61 ukuze uthole imiphumela yezempilo, okuhlanganisa nemfuneko ephansi yomthofu ye-Annex G. Ukukhetha into efanele yoketshezi olubolayo kungasingathwa ngokuthintana nomkhiqizi ukumelana namakhemikhali. liqondise futhi liqonde umphumela izinga lokushisa elizoba nawo phezu kwamandla ezinto zepulasitiki.
Nakuba i-polypropylene inengxenye yamandla e-PVC ne-CPVC, inokumelana namakhemikhali okuhlukahlukene kakhulu ngenxa yokuthi azikho izincibilikisi ezaziwayo. I-PP yenza kahle kuma-acetic acid nama-hydroxide agxilile, futhi ilungele izixazululo ezithambile zama-asidi amaningi, ama-alkali, usawoti kanye namakhemikhali amaningi emvelo.
I-PP itholakala njengento enemibala noma engenambala (yemvelo). I-Natural PP yonakaliswa kakhulu imisebe ye-ultraviolet (UV), kodwa izinhlanganisela eziqukethe ngaphezu kuka-2.5% we-carbon black pigmentation azinza ngokwanele i-UV.
Ngenxa yokuthi ama-thermoplastic azwela ukushisa, isilinganiso sokucindezela kwe-valve siyehla njengoba izinga lokushisa likhuphuka. Izinto ezihlukene zepulasitiki zine-deration ehambisanayo nezinga lokushisa elikhulayo. Izinga lokushisa eliwuketshezi lingase lingabi ukuphela komthombo wokushisa ongathinta isilinganiso sokucindezela kwamavalvu epulasitiki—izinga lokushisa eliphezulu langaphandle lidinga ukuba yingxenye yokucatshangelwa komklamo. Kwezinye izimo, ukungaklami ukushisa kwangaphandle kwamapayipi kungabangela ukuhlehla ngokweqile ngenxa yokuntuleka kwezisekelo zamapayipi. I-PVC inezinga lokushisa eliphezulu lesevisi elingu-140°F; I-CPVC inobukhulu obungu-220°F; I-PP inobukhulu obungu-180°F.
Amavalvu ebhola, amavalufu okuhlola, amavalvu ovemvane namavalvu e-diaphragm ayatholakala kuzinto ezihlukene ze-thermoplastic zohlelo lwamapayipi okucindezela angama-80 nawo anenqwaba yezinketho zokunquma kanye nezinsiza. Ivalvu yebhola ejwayelekile itholakala kakhulu iwumklamo wenyunyana wangempela ukusiza ukukhishwa komzimba we-valve ukuze ulungiswe ngaphandle kokuphazamiseka kokuxhuma amapayipi. Ama-valve okuhlola i-Thermoplastic ayatholakala njengamasheke ebhola, amasheke e-swing, ama-y-check kanye namasheke wekhoni. Amavalvu ovemvane ahlangana kalula nama-flange ensimbi ngenxa yokuthi ahambisana nezimbobo zebhawodi, imibuthano yebhawodi kanye nobukhulu bebonke be-ANSI Class 150. Ububanzi obushelelezi bangaphakathi bezingxenye ze-thermoplastic zengeza kuphela ekulawuleni okunembile kwamavalvu e-diaphragm.
Amavalvu ebhola ku-PVC naku-CPVC akhiqizwa izinkampani ezimbalwa zase-US nezakwamanye amazwe ngobukhulu obuyi-1/2 intshi ukuya ku-6 amayintshi anesokhethi, axhumene nentambo noma ane-flanged. Idizayini yangempela yenyunyana yamavalvu ebhola esimanje ihlanganisa amantongomane amabili ajiya emzimbeni, ecindezela ama-elastomeric seal phakathi komzimba nezixhumi zasekugcineni. Abanye abakhiqizi bagcine ivalve yebhola efanayo yokubeka ubude kanye nentambo yamantongomane amashumi eminyaka ukuvumela ukushintshwa kalula kwamavalvu amadala ngaphandle kokuguqulwa kumapayipi axhumene.
Ukufakwa kwe-valve uvemvane lwepulasitiki kuqondile ngoba lawa mavalvu enziwe abe yisitayela se-wafer esinama-elastomeric seals aklanywe emzimbeni. Abadingi ukungezwa kwe-gasket. Kubekwe phakathi kwama-flange amabili okukhwelana, ukuboliswa phansi kwe-valve uvemvane lwepulasitiki kufanele kusingathwe ngokucophelela ngokukhuphukela kuthoshi yebhawodi enconyiwe ngezigaba ezintathu. Lokhu kwenzelwa ukuqinisekisa uphawu olulinganayo endaweni yonke futhi kungabikho ukucindezelwa komshini okungalingani okufakwa ku-valve.
Isikhathi sokuthumela: Dec-24-2019 