ʻOiai ʻike ʻia nā ʻili wai i kekahi manawa he huahana kūikawā - kahi koho maikaʻi loa o ka poʻe e hana a hoʻolālā paha i nā huahana paipu plastik no nā ʻōnaehana ʻoihana a i ʻole nā mea hoʻomaʻemaʻe ultra-maʻemaʻe ma kahi - me ka manaʻo ʻaʻole i nui ka hoʻohana maʻamau o kēia mau pahu. ʻike ʻia.ʻO ka ʻoiaʻiʻo, ʻoi aku ka nui o ka hoʻohana ʻana o nā kīwī plastik i kēia lā e like me ka hoʻonui ʻana o nā ʻano mea hana a me nā mea hoʻolālā maikaʻi e pono ai kēlā mau mea i manaʻo nui aʻe nā ala e hoʻohana ai i kēia mau mea hana.
NA WAIWAI O PLASTIK
ʻO nā mea maikaʻi o nā valve thermoplastic he ākea-ʻo ka corrosion, kemika a me ke kūpaʻa abrasion;pahee o loko;māmā kaumaha;maʻalahi o ka hoʻokomo;ka lōʻihi o ke ola;a haʻahaʻa ke kumu kūʻai o ke ola.ʻO kēia mau mea maikaʻi i alakaʻi i ka ʻae nui ʻana i nā valve plastik i nā ʻoihana kalepa a me nā noi ʻoihana e like me ka hāʻawi ʻana i ka wai, ka mālama ʻana i ka wai ʻino, ka metala a me ka hana kemika, nā meaʻai a me nā lāʻau lapaʻau, nā mea kanu mana, nā ʻaila hinu a me nā mea hou aku.
Hiki ke hana ʻia nā valve plastik mai nā ʻano mea like ʻole i hoʻohana ʻia i kekahi mau hoʻonohonoho.Hana ʻia nā kīwī thermoplastic maʻamau me ka polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), polypropylene (PP), a me ka polyvinylidene fluoride (PVDF).Hoʻohui pinepine ʻia nā kiwikā PVC a me CPVC i nā ʻōnaehana paipu ma nā ʻaoʻao kumu hoʻoheheʻe hoʻoheheʻe ʻana, a i ʻole nā ʻaoʻao wili a me nā flanged;akā, koi ʻo PP a me PVDF e hoʻohui i nā ʻāpana ʻōnaehana paipu, ma o nā ʻenehana wela, butt- a i ʻole electro-fusion.
ʻOi aku ka maikaʻi o nā valve Thermoplastic i nā kaiapuni corrosive, akā ua like lākou me ka pono i ka lawelawe wai maʻamau no ka mea ʻaʻole lākou ke alakaʻi 1, pale i ka dezincification a ʻaʻole e pala.Pono e ho'āʻo a hōʻoia ʻia nā ʻōnaehana paipu PVC a me CPVC i ka NSF [National Sanitation Foundation] maʻamau 61 no nā hopena olakino, me ke koi haʻahaʻa haʻahaʻa no Annex G. ʻO ke koho ʻana i nā mea kūpono no nā wai corrosive hiki ke mālama ʻia ma ke kūkākūkā ʻana i ke kūpaʻa kemika o ka mea hana. alakaʻi a hoʻomaopopo i ka hopena o ka wela ma luna o ka ikaika o nā mea plastik.
ʻOiai ʻo ka polypropylene ka hapalua o ka ikaika o PVC a me CPVC, loaʻa iā ia ke kūpaʻa kemika nui loa no ka mea ʻaʻohe mea hoʻohenehene i ʻike ʻia.Hana maikaʻi ʻo PP i nā ʻakika acetic concentrated a me nā hydroxides, a ua kūpono hoʻi ia no nā hoʻonā haʻahaʻa o ka hapa nui o nā waikawa, alkalis, paʻakai a me nā kinikona he nui.
Loaʻa ʻia ʻo PP ma ke ʻano he pigmented a i ʻole nā mea ʻole (maoli).Hoʻohaʻahaʻa nui ʻia ka PP kūlohelohe e ka radiation ultraviolet (UV), akā ua hoʻopaʻa pono ʻia nā pūhui i ʻoi aku ma mua o 2.5% carbon black pigmentation.
Hoʻohana ʻia nā ʻōnaehana paipu PVDF i nā ʻano ʻoihana like ʻole mai ka lāʻau lapaʻau a i ka mining ma muli o ka ikaika o PVDF, ka mahana hana a me ke kūpaʻa kemika i nā paʻakai, nā waikawa ikaika, nā kumu dilute a me nā mea hoʻoheheʻe organik he nui.ʻAʻole like me PP, ʻaʻole hoʻohaʻahaʻa ʻia ka PVDF e ka lā;akā naʻe, akaka ka plastic i ka lā a hiki ke hōʻike i ka wai i ka radiation UV.ʻOiai he mea maikaʻi loa ka hoʻokumu ʻia ʻana o ka PVDF no ka maʻemaʻe kiʻekiʻe, ka hoʻohana ʻana i loko, me ka hoʻohui ʻana i kahi puaʻa e like me ka ʻulaʻula meaʻai e ʻae i ka ʻike ʻana i ka lā me ka ʻole o ka hopena maikaʻi ʻole i ke ʻano wai.
Loaʻa i nā ʻōnaehana plastik nā pilikia hoʻolālā, e like me ka naʻau i ka wela a me ka hoʻonui ʻana a me ka hoʻohaʻahaʻa ʻana, akā hiki i nā ʻenekinia ke hana a hoʻolālā i nā ʻōnaehana paipu maikaʻi loa no nā kaiapuni maʻamau a me ka corrosive.ʻO ka manaʻo nui o ka hoʻolālā ʻana, ʻoi aku ka nui o ka coefficient o ka hoʻonui wela no nā plastics ma mua o ka metala - ʻo ka thermoplastic he ʻelima a ʻeono manawa o ke kila, no ka laʻana.
I ka hoʻolālā ʻana i nā ʻōnaehana paipu a me ka noʻonoʻo ʻana i ka hopena i ka hoʻokomo ʻana i ka valve a me nā kākoʻo valve, kahi mea nui e noʻonoʻo ai i ka thermoplastics ka elongation thermal.Hiki ke hōʻemi a hoʻopau ʻia nā koʻikoʻi a me nā ikaika i loaʻa mai ka hoʻonui ʻana i ka wela a me ka hoʻopau ʻana ma o ka hāʻawi ʻana i ka maʻalahi i nā ʻōnaehana paipu ma o ka hoʻololi pinepine ʻana i ke kuhikuhi a i ʻole ka hoʻokomo ʻana i nā puka lou.Ma ka hāʻawi ʻana i kēia maʻalahi ma ka ʻōnaehana paipu, ʻaʻole koi ʻia ka valve plastic e komo i ka nui o ke kaumaha
Ma muli o ka maʻalahi o ka thermoplastics i ka wela, e emi ana ka helu kaomi o ka valve i ka piʻi ʻana o ka mahana.Loaʻa i nā mea plastik like ʻole ka deration me ka piʻi ʻana o ka mahana.ʻAʻole paha ʻo ka wela o ka wai wale nō ke kumu wela e hiki ke hoʻopilikia i ka helu kaomi ʻana o nā kiwi palaki—ʻo ka wela o waho ke kiʻekiʻe e pono e lilo i ʻāpana o ka noʻonoʻo ʻana.I kekahi mau hihia, ʻaʻole i hoʻolālā ʻia no ka wela o waho e hiki ke hoʻonui i ka sagging ma muli o ka nele o nā kākoʻo paipu.He 140°F ka mahana lawelawe o PVC;Loaʻa i ka CPVC ka lōʻihi o 220°F;Loaʻa iā PP ka 180°F kiʻekiʻe;a hiki i nā kiwi PVDF ke mālama i ke kaomi a hiki i 280°F
Ma ka ʻaoʻao ʻē aʻe o ka pālākiō wela, hana maikaʻi ka hapa nui o nā ʻōnaehana paipu plastik i nā mahana ma lalo o ka hau.ʻOiaʻiʻo, piʻi ka ikaika tensile i ka paipu thermoplastic i ka emi ʻana o ka mahana.Eia nō naʻe, e emi ana ke kūpaʻa hopena o ka hapa nui o nā plastics i ka hāʻule ʻana o ka mahana, a ʻike ʻia ka palupalu i nā mea paipu i hoʻopilikia ʻia.ʻOiai ʻaʻole i hoʻopilikia ʻia nā kiwi a me nā ʻōnaehana paipu e pili ana, ʻaʻole i pilikia i ka paʻi ʻana a i ʻole ke kuʻi ʻana o nā mea, a ʻaʻole i hāʻule ka paipu i ka wā e lawelawe ai, e hōʻemi ʻia nā hopena ʻino i ka paipu plastik.
NA ANO O NA WAIWAI THERMOPLASTIC
Loaʻa nā kiwi kinipōpō, nā kiwi hoʻopaʻa, nā kiwi lele a me nā kiwi diaphragm i kēlā me kēia o nā mea thermoplastic like ʻole no ka papa kuhikuhi 80 puʻupuʻu puʻupuʻu paipu i loaʻa pū kekahi o nā koho ʻoki a me nā mea pono.ʻO ka valve pōleʻa maʻamau ka mea maʻamau i ʻike ʻia he hoʻolālā uniona maoli e hoʻomaʻamaʻa i ka wehe ʻana i ke kino valve no ka mālama ʻana me ka ʻole o ka hoʻopili ʻana i ka paipu.Loaʻa nā kiwi hoʻopaʻa Thermoplastic e like me ka nānā ʻana i ka pōleʻa, nā loiloi koʻi, nā y-checks a me nā māka cone.Hoʻopaʻa maʻalahi nā kiwi kīpē me nā ʻāpana metala no ka mea ua kūlike lākou i nā puka pōʻai, nā pōʻai pōʻai a me nā ana holoʻokoʻa o ANSI Class 150. ʻO ke anawaena maʻemaʻe o loko o nā ʻāpana thermoplastic e hoʻohui wale i ka mana pololei o nā kiwi diaphragm.
Hana ʻia nā ʻāpana kinipōpō ma PVC a me CPVC e kekahi mau hui US a me nā ʻāina ʻē i ka nui o 1/2 iniha a hiki i 6 iniha me ke kumu, nā kaula a i ʻole nā loulou flanged.ʻO ka hoʻolālā uniona maoli o nā kīpē pōleʻa o kēia wā e loaʻa i ʻelua mau nati e wili ana i ke kino, e hoʻopaʻa ana i nā sila elastomeric ma waena o ke kino a me nā mea hoʻopili hope.Ua mālama kekahi po'e mea hana i ka lō'ihi o ka ho'opa'a 'ana i ka valve pōle'ele a me nā kaula nut no nā makahiki he 'umi e hiki ai ke ho'ololi ma'alahi i nā valve kahiko me ka ho'ololi 'ole i ka paipu pili.
Pono e hōʻoia i ka NSF-61G nā pahu pahu me ka ethylene propylene diene monomer (EPDM) e hoʻohana i ka wai inu.Hiki ke hoʻohana ʻia nā sila elastomeric Fluorocarbon (FKM) ma ke ʻano he mea ʻē aʻe no nā ʻōnaehana kahi e hopohopo ai ka hoʻohālikelike kemika.Hiki ke hoʻohana ʻia ka FKM i ka hapa nui o nā noi e pili ana i nā ʻakika mineral, koe wale ka hydrogen chloride, nā paʻakai paʻakai, chlorinated hydrocarbons a me nā aila ʻaila.
PVC a me CPVC poepoe kiwikā, 1/2-'īniha a hiki i 2 'īniha, he koho kūpono no ka wai wela a me ka wai anuanu kahi e hiki ai ka nui o ka lawelawe wai ho'ōho 'ole e like me 250 psi ma 73°F.'Oi aku ka nui o na kiwi poepoe, 2-1/2 'īniha a hiki i 6 'īniha, e loa'a i ka helu kaomi ha'aha'a o 150 psi ma 73°F.Hoʻohana maʻamau ʻia i ka lawe ʻana i nā kemika, nā kiwi pōpō PP a me PVDF (Nā Kiʻi 3 a me 4), loaʻa i nā nui 1/2-iniha a hiki i 4 iniha me ke kumu, kaula a i ʻole nā hopena flanged-hopena e helu pinepine ʻia i kahi lawelawe wai hoʻohālua ʻole. 150 psi i ka wela ambient.
Ke hilinaʻi nei nā kiwi pōleʻa Thermoplastic i ka pōpō me ka ʻumekaumaha kikoʻī ʻoi aku ka liʻiliʻi o ka wai, no laila inā e nalowale ke kaomi ma ka ʻaoʻao i uka, e hoʻi hou ka pōleʻa i ka ʻili o ka sila.Hiki ke hoʻohana ʻia kēia mau valves i ka lawelawe like me nā valve ball plastic like no ka mea ʻaʻole lākou e hoʻolauna i nā mea hou i ka ʻōnaehana.Hiki i nā ʻano ʻano ʻokoʻa ʻē aʻe ke hoʻokomo i nā pūnāwai metala ʻaʻole hiki ke hoʻopaʻa ʻia ma nā wahi ʻino.
He mea kaulana ka valve butterfly plastic i ka nui o 2 inches a hiki i 24 inches no nā ʻōnaehana paipu anawaena.ʻO nā mea hana o nā kiwi lele plastik e lawe i nā ala like ʻole i ke kūkulu ʻana a me ka hoʻopaʻa ʻana i nā papa.Hoʻohana kekahi i kahi liner elastomeric (Figure 5) a i ʻole O-ring, aʻo kekahi e hoʻohana i kahi diski i uhi ʻia e ka elastomeric.Hana kekahi i ke kino mai loko mai o ka mea hoʻokahi, akā ʻo nā ʻāpana i hoʻomaloʻo ʻia e lilo i mea ʻōnaehana, ʻo ia hoʻi he polypropylene butterfly valve body hiki ke loaʻa kahi liner EPDM a me PVC disc a i ʻole kekahi mau hoʻonohonoho ʻē aʻe me nā thermoplastics maʻamau a me nā sila elastomeric.
He mea maʻalahi ka hoʻokomo ʻana i ka valve butterfly no ka mea ua hana ʻia kēia mau kiwi i ke ʻano wafer me nā sila elastomeric i hoʻolālā ʻia i loko o ke kino.ʻAʻole pono lākou e hoʻohui i kahi gasket.E hoʻonoho ʻia ma waena o ʻelua mau lehelehe male, pono e mālama ʻia me ka mālama ʻana i ka bolting down of a plastic butterfly valve ma ka piʻi ʻana i ka torque bolt i ʻōlelo ʻia i ʻekolu mau pae.Hana ʻia kēia i mea e hoʻopaʻa pono ai i ka sila ma luna o ka ʻili a ʻaʻole i kau ʻia ke koʻikoʻi mechanical ʻole ma ka valve.
E ʻike ka poʻe loea valve metala i nā hana kiʻekiʻe o nā kiwi diaphragm plastic me ka huila a me nā hōʻailona kūlana i kamaʻāina (Figure 6);akā naʻe, hiki i ka pahu diaphragm plastic ke hoʻokomo i kekahi mau pōmaikaʻi ʻokoʻa me nā paia o loko o ke kino thermoplastic.E like me ka pahu pōpō plastik, hiki i nā mea hoʻohana o kēia mau valve ke koho e hoʻokomo i ka hoʻolālā uniona maoli, hiki ke hoʻohana pono no ka hana mālama ʻana i ka valve.A i ʻole, hiki i kahi mea hoʻohana ke koho i nā pili flanged.Ma muli o nā koho āpau o ke kino a me nā mea diaphragm, hiki ke hoʻohana ʻia kēia valve i nā ʻano hana kemika.
E like me kēlā me kēia valve, ʻo ke kī i ka hoʻokō ʻana i nā valve plastic ke hoʻoholo nei i nā koi hana e like me ka pneumatic versus electric a me DC versus AC mana.Akā me ka plastic, pono e hoʻomaopopo ka mea hoʻolālā a me ka mea hoʻohana i ke ʻano o ke kaiapuni e hoʻopuni ai i ka mea hana.E like me ka mea i haʻi mua ʻia, he koho maikaʻi loa nā valve plastic no nā kūlana corrosive, e komo pū ana me nā wahi corrosive waho.Ma muli o kēia, he mea koʻikoʻi ka noʻonoʻo ʻana i ka mea hale o nā actuators no nā valve plastic.Loaʻa i nā mea hana valve plastik nā koho e hoʻokō i nā pono o kēia mau wahi corrosive ma ke ʻano o nā mea hana i uhi ʻia i ka plastik a i ʻole nā hihia metala epoxy-coated.
E like me ka hōʻike ʻana o kēia ʻatikala, hāʻawi nā pahu plastik i kēia lā i nā ʻano koho āpau no nā noi a me nā kūlana hou
Ka manawa hoʻouna: Iulai-30-2020