Ukwandiswa kokuFikelela kweeValufa zePlastiki

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 zeevalvu zeplastiki zibanzi-i-corrosion, i-chemical and abrasion resistance 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 leenguqu. Iivalvu zeplastiki eziqhelekileyo zenziwe nge-polyvinyl chloride (PVC), i-polyvinyl chloride eyi-chlorinated (CPVC), i-polypropylene (PP), kunye ne-polyvinylide 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.

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.

Iinkqubo zemibhobho ye-PVDF zisetyenziswa kwiintlobo ngeentlobo zezicelo zemizi-mveliso ukusuka kumayeza ukuya emigodini ngenxa yamandla e-PVDF, ubushushu obusebenzayo kunye nokumelana neekhemikhali kwiityuwa, ii-asidi ezinamandla, iziseko ezidityanisiweyo kunye nezinyibilikisi ezininzi zezinto eziphilayo. Ngokungafaniyo nePP, iPVDF ayithotywanga kukukhanya kwelanga; nangona kunjalo, iplastiki iyabonakala ekukhanyeni kwelanga kwaye inokuveza ulwelo kwimitha ye-UV. Ngelixa i-PVDF yendalo, i-unpigmented formulation igqwesile kucoceko oluphezulu, izicelo zangaphakathi, ukongeza ibala elibomvu elifana nokutya okubomvu kuya kuvumela ukuchanabeka elangeni ngaphandle kwesiphumo esibi kwindlela yolwelo.