Nangona iivalvu zeplastiki maxa wambi zibonwa njengemveliso ekhethekileyo—ukhetho oluphezulu kwabo benza okanye bayile iimveliso zemibhobho yeplastiki kwiinkqubo zoshishino okanye abafanele babe nezixhobo ezicoceke kakhulu endaweni—becinga ukuba ezi zivalo azinakusetyenziswa ngokuqhelekileyo kufutshane— ukubona. Enyanisweni, iivalvu zeplastiki namhlanje zineendlela ezininzi zokusetyenziswa njengoko iintlobo ezandayo zezixhobo kunye nabayili abalungileyo abafuna ezo zixhobo zithetha iindlela ezininzi zokusebenzisa ezi zixhobo eziguquguqukayo.
IIPROPATI ZEPLASTIKI
Iingenelo zee-valve ze-thermoplastic zibanzi-i-corrosion, i-chemical and abrasion resistance; iindonga ezigudileyo zangaphakathi; ubunzima obulula; lula ukufakela; ixesha elide lokuphila; kunye neendleko eziphantsi zomjikelo wobomi. Ezi nzuzo ziye zakhokelela ekwamkelweni okubanzi kweevalvu zeplastiki kwizicelo zorhwebo kunye nezoshishino ezifana nokuhanjiswa kwamanzi, ukucocwa kwamanzi amdaka, ukulungiswa kwesinyithi kunye neekhemikhali, ukutya kunye namayeza, izityalo zamandla, iindawo zokucoca ioli kunye nokunye.
Iivalve zePlastiki zinokwenziwa kwinani lezinto ezahlukeneyo ezisetyenziswa kwinani loqwalaselo. Iivalve ze-thermoplastic eziqhelekileyo zenziwe nge-polyvinyl chloride (PVC), i-polyvinyl chloride eyi-chlorinated (CPVC), i-polypropylene (PP), kunye ne-polyvinylidene fluoride (PVDF). Iivalvu ze-PVC kunye ne-CPVC zidla ngokudityaniswa kwiinkqubo zokubhobhoza ngokudibanisa iziphelo zesamente ye-solvent, okanye iziphelo ezinemisonto kunye ne-flanged; kanti, iPP kunye nePVDF zifuna ukudibanisa amacandelo enkqubo yemibhobho, mhlawumbi ngobushushu, impundu- okanye iteknoloji ye-electro-fusion.
Iivalvu ze-Thermoplastic zigqwesa kwindawo enomhlwa, kodwa ziluncedo ngokufanayo kwinkonzo yamanzi ngokubanzi kuba azina lead1, ziyakwazi ukumelana ne-dezincification kwaye aziyi kurusi. Iinkqubo zemibhobho ye-PVC kunye ne-CPVC kunye neevalvu kufuneka zivavanywe kwaye zingqinwe kwi-NSF [National Sanitation Foundation] umgangatho we-61 weziphumo zempilo, kubandakanywa nemfuno ephantsi ehamba phambili yeSihlomelo G. Ukukhetha imathiriyeli efanelekileyo yolwelo oluhlwayo lunokuphathwa ngokubonisana nokumelana nemichiza yomenzi. isikhokelo kunye nokuqonda ifuthe lobushushu eliya kuba nalo kumandla ezinto zeplastiki.
Nangona i-polypropylene inesiqingatha samandla e-PVC kunye ne-CPVC, ineyona nto ixhaphakileyo yokuxhathisa imichiza ngenxa yokuba akukho zinyibilikisi ezaziwayo. I-PP iqhuba kakuhle kwi-acetic acid kunye ne-hydroxides egxininisiweyo, kwaye ifanelekile kwizisombululo ezithambileyo ze-acids ezininzi, i-alkalis, iityuwa kunye neekhemikhali ezininzi eziphilayo.
I-PP ifumaneka njenge-pigmented or unpigmented (yendalo). I-PP yendalo yonakaliswa kakhulu yimitha ye-ultraviolet (UV), kodwa iikhompawundi eziqulethe ngaphezu kwe-2.5% ye-carbon black pigmentation i-UV izinzileyo ngokwaneleyo.
Ngenxa yokuba i-thermoplastics ivakalelwa kwiqondo lokushisa, izinga loxinzelelo lwevalve liyehla njengoko ubushushu buphakama. Izinto ezahlukeneyo zeplastiki zineempawu ezihambelanayo kunye nokunyuka kobushushu. Iqondo lobushushu lolwelo lisenokungabi ngowona mthombo wobushushu kuphela onokuchaphazela umlinganiselo woxinzelelo lweevalvu zeplastiki—ubushushu obona buninzi bangaphandle bufuna ukuba yinxalenye yoqwalaselo loyilo. Kwezinye iimeko, ukungacwangciswa kobushushu bangaphandle bombhobho kunokubangela ukudodobala okugqithisileyo ngenxa yokungabikho kwezixhasi zemibhobho. I-PVC inobushushu benkonzo obuphezulu be-140 ° F; I-CPVC inobuninzi be-220 ° F; I-PP inobuninzi be-180°F.
Iivalvu zebhola, iivalve zetshekhi, iivalve zebhabhathane kunye ne-diaphragm valves ziyafumaneka kwisixhobo ngasinye se-thermoplastic esahlukileyo kwishedyuli yeenkqubo zemibhobho yoxinzelelo lwe-80 ekwanobuninzi beendlela zokunquma kunye nezixhobo. Ivalve yebhola esemgangathweni idla ngokufunyaniswa iluyilo lomanyano lokwenyani ukuququzelela ukususwa komzimba wevalve ukulungiselela ulondolozo ngaphandle kokuphazamiseka kwemibhobho yokudibanisa. Iivalvu zokujonga i-Thermoplastic ziyafumaneka njengeetshekhi zebhola, iitshekhi zokujingi, iitshekhi kunye neetshekhi zekhowuni. Iivalve zebhabhathane zidibana ngokulula neeflange zentsimbi kuba zihambelana nemingxunya yebholiti, izangqa zebholiti kunye nemilinganiselo epheleleyo ye-ANSI yoKlasi 150. Idayamitha egudileyo yangaphakathi yamalungu e-thermoplastic yongeza kuphela kulawulo oluchanekileyo lweevalvu ze-diaphragm.
Iivalvu zebhola kwi-PVC kunye ne-CPVC zenziwe ngamaqela amaninzi ase-US kunye neenkampani zangaphandle ngobukhulu be-1/2 intshi nge-intshi ezi-6 ezinesokethi, intambo okanye i-flanged. Uyilo oluyinyani lomanyano lweevalvu zebhola zangoku lubandakanya amandongomane amabini ajija umzimba, ukucinezela izitywina ze-elastomeric phakathi komzimba kunye nezihlanganisi eziphela. Abanye abavelisi bagcine ivalve yebhola efanayo yokubeka ubude kunye nemisonto yenut kangangamashumi eminyaka ukuvumela ukutshintshwa lula kweevalvu ezindala ngaphandle kokuguqulwa kwemibhobho edibanayo.
Ukufakwa kwevalve yebhabhathane yeplastiki kuthe ngqo kuba ezi zivalo zenziwe ukuba zibe sisitayile se-wafer esinezitywina ze-elastomeric eziyilwe emzimbeni. Abafuni ukongezwa kwe-gasket. Ukuseta phakathi kweeflange ezimbini zokukhwelana, ukubolithwa kwevalve yebhabhathane yeplastiki kufuneka kuphathwe ngononophelo ngokunyuka ukuya kwitorque ecetyiswayo ngezigaba ezithathu. Oku kwenzelwa ukuqinisekisa itywina elilinganayo kuwo wonke umphezulu kwaye akukho xinzelelo lomatshini olungalinganiyo lufakwa kwivalvu.
Ixesha lokuposa: Dec-24-2019 