ʻOiainā kiwikā palakikai kekahi manawa ua manaʻo ʻia he huahana kūikawā-ʻo ke koho mua no ka poʻe e hana ana a hoʻolālā paha i nā huahana paipu plastik no nā ʻōnaehana ʻoihana a i ʻole ka poʻe e pono e loaʻa nā lako ultra-maʻemaʻe-he pōkole ia ke manaʻo nei ʻaʻole nui nā hoʻohana maʻamau o kēia mau valves-ʻike. ʻO ka ʻoiaʻiʻo, he ākea ka hoʻohana ʻana o nā valves plastik o kēia lā, no ka mea, ke hoʻomau nei ka hoʻonui ʻana o nā ʻano mea, a ʻo nā mea hoʻolālā maikaʻi e pono ai kēia mau mea, ʻo ia hoʻi, he nui nā ala e hoʻohana ai i kēia mau mea hana multifunctional.

Nā Waiwai o ka Palakiko

He ākea nā pono o nā kiwikā thermoplastic—ʻo ia hoʻi ke kūpaʻa i ka palaho, kemika a me ka abrasion; nā paia o loko he laumania; māmā; maʻalahi o ke kau ʻana; lōʻihi ka lōʻihi o ke ola; a me ke kumukūʻai haʻahaʻa o ke ola. Ua alakaʻi kēia mau pono i ka ʻae ākea ʻia o nā kiwikā plastic i nā noi kalepa a me nā ʻoihana e like me ka hoʻolaha ʻana i ka wai, ka mālama ʻana i ka wai ʻino, ka hana ʻana i ka metala a me ke kemika, ka meaʻai a me nā lāʻau lapaʻau, nā mea kanu mana, nā hale hoʻomaʻemaʻe aila a me nā moHiki ke hana ʻia nā kiwikā moPlastic mai nā mea like ʻole i hoʻohana ʻia i nā hoʻonohonoho he nui. Hana ʻia nā kiwikā thermoplastic maʻamau i ka polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), polypropylene (PP), a me ka polyvinylidene fluoride (PVDF). Hoʻopili pinepine ʻia nā kiwikā PVC a me CPVC i nā ʻōnaehana paipu e nā wēlau socket cementing solvent, a i ʻole nā ​​wēlau wili a me nā flanged; ʻoiai, pono ka PP a me PVDF i ka hoʻohui ʻana o nā ʻāpana ʻōnaehana paipu, ma o nā ʻenehana wela, butt a i ʻole electro-fusion.

ʻOi aku ka maikaʻi o nā kiwikā thermoplastic i nā wahi ʻino, akā ua like nō lākou me ka pono i ka lawelawe wai maʻamau no ka mea he ʻole lākou i ke kēpau1, kū i ka dezincification a ʻaʻole e popo. Pono e hoʻāʻo ʻia a hōʻoia ʻia nā ʻōnaehana paipu PVC a me CPVC a me nā kiwikā i ka maʻamau NSF [National Sanitation Foundation] 61 no nā hopena olakino, me ke koi haʻahaʻa o ke kēpau no Annex G. Hiki ke lawelawe ʻia ke koho ʻana i ka mea kūpono no nā wai ʻino ma ka nīnau ʻana i ke alakaʻi pale kemika a ka mea hana a me ka hoʻomaopopo ʻana i ka hopena o ka mahana ma luna o ka ikaika o nā mea plastik.

ʻOiai ʻo ka polypropylene ka hapalua o ka ikaika o PVC a me CPVC, ʻo ia ka mea kū'ē i nā kemika maʻalahi loa no ka mea ʻaʻohe mea hoʻoheheʻe i ʻike ʻia. Hana maikaʻi ʻo PP i nā waikawa acetic i hoʻopaʻa ʻia a me nā hydroxides, a kūpono hoʻi ia no nā hopena palupalu o ka hapa nui o nā waikawa, alkalis, paʻakai a me nā kemika organik he nui.

Loaʻa ka PP ma ke ʻano he mea pigmented a i ʻole pigmented ʻole (kūlohelohe). Hoʻohaumia nui ʻia ka PP kūlohelohe e ka radiation ultraviolet (UV), akā ʻo nā hui i loaʻa ma mua o 2.5% ka pigmentation kalapona ʻeleʻele ua lawa ka UV stabilized.

Hoʻohana ʻia nā ʻōnaehana paipu PVDF i nā ʻano hana ʻoihana like ʻole mai ka lāʻau lapaʻau a i ka mining ma muli o ka ikaika o ka 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 e like me PP, ʻaʻole i hoʻohaumia ʻia ka PVDF e ka lā; akā naʻe, ua moakaka ka plastic i ka lā a hiki ke hōʻike i ka wai i ka radiation UV. ʻOiai he mea maikaʻi loa ka hoʻohui kūlohelohe, ʻaʻohe pigment o PVDF no nā noi maʻemaʻe kiʻekiʻe, ʻo ka hoʻohui ʻana i kahi pigment e like me ka ʻulaʻula papa meaʻai e ʻae i ka hōʻike ʻana i ka lā me ka ʻole o ka hopena maikaʻi ʻole ma ka wai.

He mau pilikia hoʻolālā ko nā ʻōnaehana palaki, e like me ka ʻike i ka mahana a me ka hoʻonui ʻana a me ka hoʻemi ʻana o ka wela, akā hiki i nā ʻenekinia ke hoʻolālā a ua hoʻolālā i nā ʻōnaehana paipu lōʻihi a kūpono hoʻi no nā wahi ākea a me nā wahi ʻino. ʻO ka noʻonoʻo nui o ka hoʻolālā ʻana, ʻoi aku ka nui o ke koina o ka hoʻonui ʻana o ka wela no nā palaki ma mua o ka metala—ʻelima a ʻeono manawa ka thermoplastic o ke kila, no ka laʻana.

I ka hoʻolālā ʻana i nā ʻōnaehana paipu a me ka noʻonoʻo ʻana i ka hopena ma ke kau ʻana o ka valve a me nā kākoʻo valve, he mea nui ka noʻonoʻo ʻana i nā thermoplastics ʻo ia ka elongation thermal. Hiki ke hoʻemi ʻia a hoʻopau ʻia paha nā pilikia a me nā ikaika i loaʻa mai ka hoʻonui ʻana a me ka ʻūlū ʻana o ka thermal ma ka hāʻawi ʻana i ka maʻalahi i nā ʻōnaehana paipu ma o nā loli pinepine i ke kuhikuhi a i ʻole ka hoʻokomo ʻana i nā loops hoʻonui. Ma ka hāʻawi ʻana i kēia maʻalahi ma ka ʻōnaehana paipu, ʻaʻole pono ka valve plastic e omo i ka nui o ke kaumaha (Kiʻi 1).

No ka mea, he ʻano koʻikoʻi nā thermoplastics i ka mahana, e emi ana ke kaomi o kahi valve i ka piʻi ʻana o ka mahana. Loaʻa i nā mea plastik like ʻole ka deration like me ka piʻi ʻana o ka mahana. ʻAʻole paha ʻo ka mahana wai wale nō ke kumu wela e hiki ke hoʻopilikia i ke kaomi o nā valves plastik—pono ka mahana waho kiʻekiʻe loa e lilo i ʻāpana o ka noʻonoʻo ʻana i ka hoʻolālā. I kekahi mau hihia, ʻo ka hoʻolālā ʻole ʻana no ka mahana waho o ka paipu hiki ke hana i ka sagging nui ma muli o ka nele o nā kākoʻo paipu. ʻO 140°F ka mahana lawelawe kiʻekiʻe loa o PVC; 220°F ka CPVC; 180°F ka PP; a hiki i nā valves PVDF ke mālama i ke kaomi a hiki i 280°F (Kiʻi 2).

Ma kekahi ʻaoʻao o ke ana wela, hana maikaʻi ka hapa nui o nā ʻōnaehana paipu plastik i nā mahana ma lalo o ka hau. ʻO ka ʻoiaʻiʻo, piʻi ka ikaika tensile i nā paipu thermoplastic i ka emi ʻana o ka mahana. Eia nō naʻe, emi ka pale ʻana o ka hopena o ka hapa nui o nā plastik i ka emi ʻana o ka mahana, a ʻike ʻia ka brittleness i nā mea paipu i hoʻopilikia ʻia. Inā ʻaʻole i hoʻopilikia ʻia nā valves a me ka ʻōnaehana paipu e pili ana, ʻaʻole i hoʻoweliweli ʻia e nā hahau a i ʻole ke kuʻi ʻana o nā mea, a ʻaʻole i hāʻule ka paipu i ka wā e lawelawe ai, ua hoʻemi ʻia nā hopena maikaʻi ʻole i nā paipu plastik.

Nā ʻAno o nā Valve Thermoplastic

Nā kiwikā poepoe,nā kiwikā nānā,nā kiwikā pepekea loaʻa nā kiwikā diaphragm i kēlā me kēia o nā mea thermoplastic like ʻole no nā ʻōnaehana paipu kaomi papa 80 i loaʻa pū kekahi mau koho hoʻonaninani a me nā mea pono. ʻO ka kiwikā pōpō maʻamau ka mea i ʻike pinepine ʻia he hoʻolālā hui maoli e hoʻomaʻamaʻa i ka wehe ʻana i ke kino kiwikā no ka mālama ʻana me ka ʻole o ka hoʻopilikia ʻana i ka hoʻopili ʻana i nā paipu. Loaʻa nā kiwikā nānā Thermoplastic ma ke ʻano he mau nānā pōpō, nā nānā swing, nā nānā-y a me nā nānā cone. Hoʻopili maʻalahi nā kiwikā butterfly me nā flanges metala no ka mea kūlike lākou me nā lua bolt, nā pōʻai bolt a me nā ana holoʻokoʻa o ANSI Class 150. ʻO ke anawaena o loko o nā ʻāpana thermoplastic e hoʻohui wale i ka mana pololei o nā kiwikā diaphragm.

Hana ʻia nā kiwikā pōpō ma PVC a me CPVC e kekahi mau ʻoihana US a me nā ʻāina ʻē i nā nui 1/2 ʻīniha a hiki i 6 ʻīniha me nā pilina socket, wili a i ʻole flanged. ʻO ka hoʻolālā hui maoli o nā kiwikā pōpō o kēia wā e komo pū ana me ʻelua mau nati e wili ana ma ke kino, e hoʻopaʻa ana i nā sila elastomeric ma waena o ke kino a me nā mea hoʻohui hopena. Ua mālama kekahi mau mea hana i ka lōʻihi like o ke kau ʻana o ka kiwikā pōpō a me nā kaula nati no nā makahiki he ʻumi e ʻae ai i ka hoʻololi maʻalahi o nā kiwikā kahiko me ka ʻole o ka hoʻololi ʻana i nā paipu pili.

Pono e hōʻoia ʻia nā kiwikā pōpō me nā sila elastomeric ethylene propylene diene monomer (EPDM) i ka NSF-61G no ka hoʻohana ʻana i ka wai inu. Hiki ke hoʻohana ʻia nā sila elastomeric Fluorocarbon (FKM) ma ke ʻano he koho ʻē aʻe no nā ʻōnaehana kahi e hopohopo ai ka hoʻohālikelike kemika. Hiki ke hoʻohana ʻia ʻo FKM i ka hapa nui o nā noi e pili ana i nā waikawa mineral, koe wale nō ka hydrogen chloride, nā hopena paʻakai, nā hydrocarbons chlorinated a me nā aila petroleum.

Kiʻi 3. He kiwikā pōpō flanged i hoʻopili ʻia i kahi pahu waiKiʻi 4. He kiwikā nānā pōpō i hoʻokomo pololei ʻia ʻO nā kiwikā pōpō PVC a me CPVC, 1/2-ʻīniha a hiki i 2 ʻīniha, he koho kūpono no nā noi wai wela a me ke anuanu kahi e hiki ai i ka lawelawe wai ʻole-haʻalulu kiʻekiʻe loa e like me 250 psi ma 73°F. ʻO nā kiwikā pōpō nui aʻe, 2-1/2 ʻīniha a hiki i 6 ʻīniha, e loaʻa ka helu kaomi haʻahaʻa o 150 psi ma 73°F. Hoʻohana pinepine ʻia i ka lawe ʻana i nā kemika, nā kiwikā pōpō PP a me PVDF (Kiʻi 3 a me 4), loaʻa i nā nui 1/2-ʻīniha a hiki i 4 ʻīniha me ka socket, threaded a i ʻole nā ​​​​pilina flanged-end i helu pinepine ʻia i ka lawelawe wai ʻole-haʻalulu kiʻekiʻe loa o 150 psi ma ka mahana ambient.

Hilinaʻi nā kiwikā nānā pōpō thermoplastic i kahi pōpō me ka umekaumaha kikoʻī ma lalo o ka wai, no laila inā nalowale ke kaomi ma ka ʻaoʻao uka, e piholo hou ka pōpō i ka ʻili sila. Hiki ke hoʻohana ʻia kēia mau kiwikā ma ka lawelawe like me nā kiwikā pōpō plastik like no ka mea ʻaʻole lākou e hoʻokomo i nā mea hou i ka ʻōnaehana. Hiki i nā ʻano kiwikā nānā ʻē aʻe ke komo pū me nā pūnāwai metala ʻaʻole paha e mau i nā wahi ʻino.

Kiʻi 5. He kiwikā pepeke me ka liner elastomeric ʻO ka kiwikā pepeke palakiko i nā nui mai 2 ʻīniha a 24 ʻīniha he mea kaulana ia no nā ʻōnaehana paipu nui aʻe. Lawe nā mea hana o nā kiwikā pepeke palakiko i nā ʻano hana like ʻole i ke kūkulu ʻana a me ka sila ʻana i nā ʻili. Hoʻohana kekahi i kahi liner elastomeric (Kiʻi 5) a i ʻole O-ring, aʻo kekahi e hoʻohana i kahi diski i uhi ʻia me ka elastomeric. Hana kekahi i ke kino mai hoʻokahi mea, akā ʻo nā ʻāpana kūloko, i pulu ʻia e lawelawe ma ke ʻano he mau mea ʻōnaehana, ʻo ia hoʻi, hiki i ke kino kiwikā pepeke palakiko polypropylene ke loaʻa kahi liner EPDM a me ka diski PVC a i ʻole kekahi mau hoʻonohonoho ʻē aʻe me nā thermoplastics i loaʻa pinepine a me nā sila elastomeric.

He maʻalahi ke kau ʻana o kahi kiwikā pepeke plastik no ka mea ua hana ʻia kēia mau kiwikā e like me ke ʻano wafer me nā sila elastomeric i hoʻolālā ʻia i loko o ke kino. ʻAʻole pono lākou e hoʻohui i kahi gasket. Ma waena o ʻelua mau flanges mating, pono e mālama pono ʻia ka hoʻopaʻa ʻana o kahi kiwikā pepeke plastik ma ka piʻi ʻana i ka torque bolt i ʻōlelo ʻia i ʻekolu mau pae. Hana ʻia kēia e hōʻoia i kahi sila like ma ka ʻili a ʻaʻohe pilikia mechanical like ʻole e kau ʻia ma ka kiwikā.

Kiʻi 6. He kiwikā diaphragmE ʻike nā loea kiwikā metala i nā hana kiʻekiʻe o nā kiwikā diaphragm plastik me nā hōʻailona huila a me ke kūlana i kamaʻāina (Kiʻi 6); akā naʻe, hiki i ka kiwikā diaphragm plastik ke hoʻokomo i kekahi mau pono kūikawā e like me nā paia maʻemaʻe o loko o ke kino thermoplastic. E like me ka kiwikā pōpō plastik, loaʻa i nā mea hoʻohana o kēia mau kiwikā ke koho e hoʻokomo i ka hoʻolālā hui maoli, hiki ke lilo i mea pono no ka hana mālama ma ka kiwikā. A i ʻole, hiki i ka mea hoʻohana ke koho i nā pilina flanged. Ma muli o nā koho āpau o ke kino a me nā mea diaphragm, hiki ke hoʻohana ʻia kēia kiwikā i nā ʻano noi kemika like ʻole.

E like me nā kiwikā a pau, ʻo ke kī i ka hoʻāla ʻana i nā kiwikā palakika ʻo ia ka hoʻoholo ʻana i nā koi hana e like me ka pneumatic versus uila a me ka mana DC versus AC. Akā me ka palakika, pono nō hoʻi ka mea hoʻolālā a me ka mea hoʻohana e hoʻomaopopo i ke ʻano o ke kaiapuni e hoʻopuni ai i ka actuator. E like me ka mea i ʻōlelo ʻia ma mua, he koho maikaʻi loa nā kiwikā palakika no nā kūlana ʻino, e komo pū ana me nā kaiapuni ʻino o waho. Ma muli o kēia, he mea nui ka noʻonoʻo ʻana i nā mea hale o nā actuators no nā kiwikā palakika. Loaʻa i nā mea hana kiwikā palakika nā koho e hoʻokō i nā pono o kēia mau kaiapuni ʻino ma ke ʻano o nā actuators i uhi ʻia i ka palakika a i ʻole nā ​​​​​​hihia metala i uhi ʻia i ka epoxy.

E like me ka mea i hōʻike ʻia ma kēia ʻatikala, hāʻawi nā kiwikā plastik i kēia lā i nā ʻano koho like ʻole no nā noi hou a me nā kūlana.