Indawo encibilikayo yekristalu ye-PTFE ingu-327℃, kodwa inhlaka kufanele ibe ngaphezu kuka-380℃ ukuze ibe sesimweni sokuncibilika.Ngaphezu kwalokho, i-PTFE inokumelana ne-solvent enamandla kakhulu.Ngakho-ke, ayikwazi ukusebenzisa noma ukucutshungulwa kokuncibilika noma ukucutshungulwa kokuqedwa.Ngokuvamile, ukukhiqizwa kwemikhiqizo yayo kungenziwa kuphela njengokucubungula kwensimbi ne-ceramic.Impushana iqala ihlanganiswe, bese i-sintered futhi ifakwe ngomshini, noma yenziwe nge-extrusion, i-Isobaric forming, i-coating forming, kanye nokwakheka kwe-calendering.
Indawo encibilikayo yekristalu ye-PTFE ingu-327℃, kodwa inhlaka kufanele ibe ngaphezu kuka-380℃ ukuze ibe sesimweni sokuncibilika.Ngaphezu kwalokho, i-PTFE inokumelana ne-solvent enamandla kakhulu.Ngakho-ke, ayikwazi ukusebenzisa noma ukucutshungulwa kokuncibilika noma ukucutshungulwa kokuqedwa.Ngokuvamile, ukukhiqizwa kwemikhiqizo yayo kungenziwa kuphela njengokucubungula kwensimbi ne-ceramic.Impushana iqala ihlanganiswe, bese i-sintered futhi ifakwe ngomshini, noma yenziwe nge-extrusion, i-Isobaric forming, i-coating forming, kanye nokwakheka kwe-calendering.
Ukubunjwa Kokucindezela
Ukubunjwa kwe-Compression yikona kakhuluUkucubungula ukubumba kwe-PTFEindlela esetshenziswa njengamanje ku-PTFE.Inqubo yokubumba iyindlela lapho izinto ezithile zokubumba (ama-powder, ama-pellets, izinto ze-fibrous, njll.) zifakwa esikhunjini sensimbi futhi zibunjwe ekushiseni okuthile nokucindezela.I-polymer ecutshungulwa ngokubunjwa kokucindezela ayinqunyelwe isisindo sayo samangqamuzana, futhi cishe wonke amapulasitiki angacutshungulwa ngokubunjwa kokucindezelwa.Izici eziyinhloko zokubunjwa kokucindezela yilezi: izindleko eziphansi, imishini elula, ukutshalwa kwezimali okuphansi, futhi akunqunyelwe isisindo samangqamuzana epulasitiki esenziwe;ukungalungi ukusebenza kahle kokukhiqiza, izinga eliphezulu labasebenzi, kanye nekhwalithi yomkhiqizo engazinzile.Isisindo samangqamuzana esihlobene se-PTFE siphezulu kakhulu futhi uketshezi lubi ngokwedlulele.Lapho ezinye izindlela zokucubungula zingavuthiwe, amazwe emhlabeni jikelele asebenzisa kakhulu ukubumba ukucindezela imikhiqizo ye-PTFE.
Inqubo ethize yokubunjwa kokucindezelwa ihlukaniswe yaba ① indlela yokucindezela-sinter-press;② indlela ye-sinter-press;③ indlela yokushisa-cindezela ngokushesha;④ cindezela futhi sinter kanyekanye.
I-Hydroforming
Indlela ye-hydraulic ibizwa nangokuthi indlela yokulinganisa kanye nendlela yokucindezela elinganayo, okuwukwengeza inhlaka ye-PTFE ngokulinganayo phakathi kwesikhwama senjoloba nodonga lwesikhunta, bese ujova uketshezi (amanzi asetshenziswa ngokuvamile) esikhwameni senjoloba, kanye nesikhwama senjoloba esikhiqizayo. ingcindezi inwebeka odongeni lwesikhunta futhi i-compact Resin iba yindlela yama-preforms.Le ndlela ingasetshenziswa ukwenza imikhono emikhudlwana, amathangi okugcina aphansi, amagobolondo angama-hemispherical, amakholomu ombhoshongo, ama-slabs amakhulu, njll., futhi ingasetshenziswa ukwenza amateyi, izindololwane, izinto ezinephrofayili, njll. ngesakhiwo esiyinhlanganisela ye-PTFE esifakwe umugqa ngokuphelele.Imikhiqizo enezimo eziyinkimbinkimbi.Inzuzo eyinhloko ye-hydroforming yisakhiwo esilula semishini kanye nesikhunta.Iphampu yamanzi evamile ithatha indawo yomshini wokunyathelisa onamathani aphezulu.Umkhiqizo ucindezelwe ngokufanayo, unokuminyana okungaguquki, ungakha izingxenye ezinkulu, unomumo oyinkimbinkimbi, kanye nezakhiwo ezilula zamalayini.
Ukwakhiwa kwe-Push
Ukusunduza kubizwa nangokuthinamathisela i-extrusionukubumba.I-20-30 mesh sieved dispersing resin ixubene nezithasiselo eziphilayo (i-toluene, i-petroleum ether, uwoyela we-solvent, njll., ingxenye yesisindo se-resin yi-1/5) ukwenza unamathisele.Icindezelwe ngaphambilini ibe yindilinga enodonga olungenalutho olungenalutho olungenalutho, bese iyifaka ezintweni zokunyathelisa, bese usebenzisa i-plunger ukuyikha ngaphansi kokushisisa.Ngemuva kokoma, ifakwe emanzini ekushiseni okungama-360 ~ 380C, futhi ngemva kokupholisa, kutholakala ishubhu eliqinile, induku, neminye imikhiqizo.Imikhiqizo ephushwayo inqunyelwe ezintini ezinobubanzi obungu-16mm noma ngaphansi namapayipi anogqinsi oluyi-3mm noma ngaphansi.
Ukubunjwa kwe-Spiral extrusion
I-screw extruder ye-PTFE powder ihlukile kune-extruder esetshenziselwa amanye ama-thermoplastics.Ukubunjwa kwe-extrusion kwe-Zengtong thermoplastics ukuthuthukisa impahla ngokuzungezisa isikulufu, kuyilapho kudlala indima yokucindezelwa, ukugunda, nokuxuba., Izinto ezibonakalayo ziphinde zincibilike ngokushisa okukhiqizwa amandla amakhulu kanye nokushisa kwangaphandle kwempahla.Isikulufu se-PTFE screw extruder sidlala kuphela indima yokudlulisa nokusunduza, ukuze impahla idlule ekhanda le-screw extruder enemicu ephindwe kabili, iphimbo elilinganayo nokujula okulinganayo, bese ingena endaweni yokufa yokucwilisa, Ukupholisa. kanye nokubumba ngokucindezela okunikezwa idivayisi ye-backpressure ukufeza injongo eqhubekayo.Lapho ucubungula i-PTFE nge-scruder eyodwa yesikulufa, ubunzima obukhulu kuvame ukuhlangana nabo.Ngenxa yokuthi i-friction coefficient ye-PTFE powder iphansi kakhulu, ibangela ukushelela phakathi nenqubo yokudla, okunciphisa kakhulu umthamo wokudlulisa wesikulufu.Ngaphezu kwalokho, ngenxa yokungqubuzana nokukhiqiza ukushisa, impushana ingase inamathele kusikulufa noma emgqonyeni, okwenza ukudla kube nzima futhi kungazinzi.
Eminyakeni yamuva nje, izikulufu ezimbili ziye zasetshenziswa ekucubunguleni izinto zalolu hlobo olukhethekile.Umgomo wayo wokondla uhlukile kulowo we-single-screw extruder.Inomphumela omuhle wokudlulisa futhi inganqoba ukushelela kwempushana ye-UHMWPE kusikulufu.Thuthukisa kakhulu umthamo wokuphakela ngezikulufu.Phakathi kwazo, i-counter-rotation twin-screw extruder inemiphumela engcono yokuxuba kanye ne-homogenization kune-twin-screw extruder ezungezayo efanayo, kodwa ngenxa yamandla ayo amakhulu okuhlukanisa, umphumela wokugunda esikhaleni sesikulufu mkhulu, okwenza okokusebenza kushise kakhulu. futhi extrude.Isisindo samangqamuzana okukhiphayo singancishiswa cishe ngo-40%.Uma igceke lenziwa libe likhulu futhi izikulufi zingabambisene, impahla izonamathela ensimbi eshisayo.Kodwa-ke, ukusetshenziswa kwama-twin-screw extruder ajikelezayo akunazo izinkinga ezingenhla.Umphumela wokugunda wezinto eziku-extruder mncane ngokuqhathaniswa, futhi ukushisa okudingekayo kwe-plasticization konke kuvela emthonjeni wokushisa wangaphandle, ngakho-ke kungalawulwa ngokunembile ukuze ukuwohloka kokushisa okweqile kwempahla ngesikhathi senqubo ye-extrusion kungancishiswa, futhi ngesikhathi esifanayo ukugcina Ukugeleza kwezinto ezisekhanda lomshini kujwayelekile futhi kuzinzile, futhi ukuklanywa kobukhulu besigaba sekhanda lomshini kufanele kuhambisane nomthamo wezinto ezihanjiswa yi-screw.Isivinini sokuzungezisa sesikulufu asikwazi ukushesha naso, ngokuvamile sizungeze ama-revolution angu-10 ngomzuzu.Ukuze ugweme izinto ezinamathele ngokuzumayo endaweni yensimbi, izinga lokushisa le-extrusion kufanele lilawulwe ngokuqinile.
Ukwakhiwa kwe-plunger extrusion
I-Plunger extrusion molding processing processing iyindlela endala yokucubungula ipulasitiki.Kusukela kwavela izinto zepulasitiki, abantu sebeqalile ukusebenzisa le ndlela ukucubungula amapulasitiki.Ukucubungula i-PTFE nge-plunger extruder, i-resin yobuningi icindezelwa esibunjeni, i-plunger iyaphindwa, futhi icindezelwa ku-preform.Ngale ndlela, ama-preform amaningi akhiwa ku-die.Ngenxa yokungqubuzana phakathi kwe-PTFE resin kanye nokungqubuzana phakathi kwe-PTFE resin nodonga lokufa, ukumelana kuyakhiqizwa.Ngesikhathi esifanayo, ukunwetshwa kwevolumu ye-preform lapho i-sintered in the die nayo ikhiqiza ukumelana, ukuze kube yi-preform yengxenye eyodwa.I-Sintering kanye nokupholisa ngaphansi kwengcindezi yakha yonke into eqhubekayo.Izinzuzo zale ndlela yilezi: akukho ukugunda ngesikhathi sokubumba, isisindo samangqamuzana esihlobene sincishisiwe, izinga lomkhiqizo lihle, futhi alinqunyelwe isisindo samangqamuzana, futhi lingakwazi ukucubungula ububanzi obukhulu nge- ubukhulu bobukhulu obungu-500mm nobukhulu bodonga obungu-3mm kuphela.Ipayipi.Kodwa-ke, ngenxa yendawo encane yokuxhumana phakathi kwezinto eziluhlaza kanye nengxenye yokushisa ngesikhathi senqubo yokuthumela, ukusebenza kahle kokushisa kuphansi, okunciphisa isivinini se-extrusion yayo.
Isikhathi sokuthumela: Jun-14-2020