(duba kuma polymer® PTFE da polymer® FEP & PFA Specifications ) Kayan aikin injiniya na PTFE ba su da ƙasa idan aka kwatanta da sauran robobi, amma kaddarorinsa suna kasancewa a matakin amfani akan kewayon zafin jiki na -100 ° F zuwa + 400 ° F (- 73 ° C zuwa 204 ° C).
Abubuwan da aka saba na polymer® PTFE Fluoropolymer Resins
Juriya yanayin zafi
Zazzabi sama da 77°C ba su da kyau ga sassa na yawancin elastomers da robobi, yayin da PTFE ke jure yanayin zafi har zuwa 260°C.Ko da ƙasa da 77°C, idan aka haɗa acid ɗin da ke lalata da ƙarfe da abubuwan kaushi na halitta, ana fifita layin layi da kayan aikin PTFE sau da yawa saboda elastomers da sauran robobi sukan rasa juriya ga kumburin ƙarfi da laushi.
Sinadarin rashin kuzari
Ta hanyar rashin kuzarin sinadari, muna nufin cewa PTFE fluorocarbon resins na iya kasancewa cikin ci gaba da tuntuɓar wani abu ba tare da wani abin da zai iya ganowa ba.Gabaɗaya, PTFE fluorocarbon resins ba su da ƙarancin sinadarai.Duk da haka, wannan magana, kamar duk na gaba ɗaya, dole ne ta cancanta idan ana son ta zama daidai.Cancancin ba zai haifar da rudani ba, duk da haka, idan mutum ya tuna da ainihin gaskiyar game da halayen resin PTFE.
Takaitaccen bayanin da aka saba yi na bayanan gwaji daban-daban na iya zama yaudara, domin yana iya haɗa nau'ikan halayen “Chemical” daban-daban.Idan bayanin zai bayyana a sarari, dole ne ya bambanta tsakanin tsananin halayen sinadarai da ayyukan jiki kamar sha.Bayanin dole ne ya bawa mai amfani damar yin la'akari da alaƙar kayan aikin jiki da sinadarai waɗanda zasu iya shafar takamaiman aikace-aikacen.
Misali, resins na PTFE ba za su sami tasiri ba ta hanyar nutsewa a cikin ruwa regia.Amma duk da haka idan zazzabi da sakamakon sakamakon wannan reagent ya zama babba, ɗaukar abubuwan da ke cikin reagent shima zai ƙaru.Canje-canje na gaba, kamar asarar matsi na kwatsam, na iya yin lahani a jiki saboda faɗaɗa tururin da ke cikin guduro.Babu shakka, sa'an nan, idan muka magana game da sinadaran Properties na PTFE dole ne mu bambanta tsakanin tsananin sinadaran halayen, kamar yadda muka bayyana a cikin sharuddan "Chemical karfinsu" da kuma jiki ayyuka, kamar "sha" hade da inji da kuma thermal danniya.
A cikin yanayin yanayin amfani na yau da kullun, PTFE resins ana kaiwa hari da wasu sinadarai kaɗan maimakon tsara sinadarai waɗanda suka dace da su.Wadannan reactants suna daga cikin mafi tashin hankali oxidizers da rage jamiái da aka sani.Sodium elemental a cikin kusancin hulɗa tare da fluorocarbons yana cire fluorine daga kwayoyin polymer.Ana amfani da wannan dauki a ko'ina a cikin maganin anhydrous don etch saman PTFE domin resins na iya zama m bonded.Sauran karafa na alkali (potassium, lithium, da sauransu) suna amsa irin wannan.
A wasu lokuta a ko kusa da iyakar zafin sabis na 260 ° C don TFE & PFA, da 204 ° C don FEP, an ba da rahoton wasu sinadarai masu yawa a babban taro suna mayar da martani ga PTFE.An samar da hari mai kama da sodium etch a irin wannan yanayin zafi da 80% NaOH ko KOH, ƙarfe hydrides kamar boranes (misali, B2H6), aluminum chloride, ammonia (NH3), da wasu amines (R-NH2) da imines ( R = NH).Har ila yau, jinkirin harin oxidative an lura da shi ta hanyar 70% nitric acid a ƙarƙashin matsin lamba a 250 ° C.Ana buƙatar gwaji na musamman lokacin da aka kusanci irin wannan matsananciyar ragewa ko yanayin iskar oxygen.
Sha
Ya bambanta da karafa, filastik da elastomers suna ɗaukar nau'o'in nau'ikan kayan da suke tuntuɓar su, musamman ruwan ruwa.Absorptivities a cikin PTFE suna da ƙasa da ba a saba gani ba, kuma halayen sinadarai tsakanin filastik da sauran abubuwa ba su da yawa (tare da ƴan abubuwan da aka ambata a baya).Koyaya, lokacin da aka haɗa sha tare da wasu tasirin, wannan kadarar zata iya yin tasiri akan sabis na waɗannan resins a cikin wani yanayi na sinadari.Misali, idan saurin saurin yanayin zafi ko matsi ya faru, ana iya haifar da yanayi masu lahani a jiki.Faɗin zafin sabis na resins na PTFE yana fallasa su ga irin wannan lalacewar jiki akai-akai fiye da sauran robobi.
Ta hanyar bayani, bari mu yi la'akari da gwajin "zagayowar tururi" da aka kwatanta a cikin ka'idodin ATSM * don bututu mai layi.Samfurori na bututu mai layi suna ƙarƙashin 0.8MPa (125 psi) tururi, musanya tare da ƙarancin ruwan sanyi, yana haifar da matsanancin zafi da haɓakar matsa lamba hakika.Ana maimaita wannan don zagayawa 100.Turi ya haifar da matsa lamba da yanayin zafin jiki ta hanyar layin da ke haifar da ɗaukar ɗan ƙaramin tururi wanda ke tashe ruwa a cikin bangon layin.A lokacin da aka saki matsa lamba, ko kuma a sake dawo da tururi, ruwan da aka makale zai iya fadada zuwa tururi yana haifar da asalin micro pore.Matsakaicin maimaitawa da hawan keke na zafi yana haɓaka ƙananan pores, a ƙarshe yana haifar da blisters mai cike da ruwa a cikin layin.Ka'idodin ASTM sun lura cewa blisters ba sa yin illa ga aikin bututun mai - kaurin shingen sinadarai har yanzu yana nan.
Akwai matakan lalata da ke rage tsananin kumburi.Ƙunƙarar zafi na bututu mai layi ko jirgin ruwa yana rage yawan zafin jiki a cikin layin, ta haka sau da yawa yana hana tashewa da haɓakar magudanar ruwa.Hakanan ya rage gudu da girman canje-canjen zafin jiki, don haka rage kumburi.Don haka, ta hanyar rage guduro, rufi zai iya ba da ma'aunin kariya a yawancin lokuta.Ana iya samar da ƙarin kariya ta amfani da hanyoyin aiki ko na'urori waɗanda ke ƙayyadadden ƙimar rage matsi ko haɓaka zafin jiki.
Tsayawa
Zubar da ciki wani abu ne da ke da alaƙa da sha, amma kuma aiki ne na wasu tasirin jiki, kamar yaduwa da zafin jiki.A cikin fiye da shekaru 20 na gwaninta tare da bututu mai layi na PTFE, adadin gazawar da aka danganta da ratsawar tururi mai lalacewa wanda ya biyo bayan lalata memba na tallafi ya kasance kaɗan.Matsakaicin kauri na 1.27 zuwa 6.35mm wajibi ne don ƙarfin jiki a yanayin zafi mai girma yana rage zubewa har ya zama ƙaramin la'akari.Saboda sauye-sauye da yawa suna shafar ratsawa, yaudara ne don amfani da bayanan iyawar dakin gwaje-gwaje da aka samu tare da fina-finai na polymer na bakin ciki a matsayin tushen zaɓi na takamaiman rufin polymer na fluoroplastic.Baya ga ƴan kaɗan, bambance-bambance a cikin iyawa tsakanin fluoroplastics ba su da ɗan tasiri kan aikin bututun da aka ƙirƙira da kayan aiki.Ana sarrafa aiki da farko ta ƙira, ƙira da sarrafa inganci.Don haka, babban abin damuwa shine yawanci tare da sha, tunda wannan shine kayan da ya fi nuni da sabis na resin fluorocarbon a cikin yanayin da aka ba da sinadarai.
A cikin rufin da ba a da iyaka, yana da mahimmanci cewa sararin da ke tsakanin layin layi da memba na goyan baya ya fito zuwa sararin samaniya, ba wai kawai don ba da damar tserewa na minti kaɗan na tururi ba amma don hana haɓakar iska daga faɗuwar layin.Har ila yau, ana amfani da waɗannan huɗaɗɗen don gwajin kula da ingancin bututu mai layi da kuma azaman na'urar aminci don nuna ɗigogi a yanayin lalacewar layin.Sau da yawa ana danganta rugujewar layi zuwa ga ɓarna yayin da ainihin dalilin farko shine faruwar vacuum a cikin magudanar ruwa.Masu kera bututun da aka lika suna buga juriya ga injin injin da aka ƙididdige girman girmansu daban-daban da kaurin layinsu, amma wani lokaci yakan zama dole don hana ƙura da ƙura ta hanyar ƙirar ƙira da hanyoyin aiki.
Lokacin aikawa: Fabrairu-14-2019