Nangona irabha ye-nitrile butadiene (NBR) ibiyeyona nto iphambili yokutywina i-injini yomoya kumashumi eminyaka, inkqubela phambili yokwenziwa kwetywina le-polyurethane, ukusetyenzwa kunye noyilo kukhawuleza kukhukulise isikhundla se-NBR kushishino.Kuyavela ukuba ezona zixhobo ziluncedo kakhulu zibandakanya ukumelana nokunxiba, ukuhambelana kwamanzi, ukuxhathisa kwe-ozone, amandla omatshini, kunye nokukwazi ukugcina zonke ezi zakhiwo kumaqondo obushushu aphantsi.
I-polyurethane iye yaba yinto efanelekileyo yokutywina iibheringi eziphambili / iijeneretha, iibheringi ezinde kunye nezinqamlezayo.Nangona kunjalo, ukutshintsha nje izixhobo kwisakhiwo esele sikhona akwanele.Izitywina kufuneka zenziwe nge-polyurethane engqondweni.
Enye indlela yokuvavanya ukuxhathisa kokunxiba kwe-polyurethanes kungovavanyo oluqhelekileyo lokunxiba igubu elifana ne-ASTM D5963.Le ndlela iqhele ukusetyenziselwa ukuvavanya irabha, kodwa ikwasebenza nakwi-polyurethane, ngakumbi xa kuthelekiswa amaxabiso okunxiba.Apha ngezantsi kukho amaxabiso esalathiso sezinto ezahlukeneyo ezivavanywe ziiSistim zeSistim eCleveland.Qaphela ukuba i-NBR kunye ne-HNBR ine-ARI malunga ne-1.5, ngelixa i-polyurethanes ine-ARI ye-4 ukuya kwi-8. Oku kuphuculwa ukuya kumaxesha amathandathu.
I-Polyurethane igcina amaxabiso ayo e-ARI ngokuhamba kwexesha nasemva kokuvezwa kulwelo olwahlukeneyo, ngakumbi ulwelo olusekwe kwioyile.Enye indlela yokumisela oku kukuguga i-ASTM D5963 iisampulu zokunxiba kulwelo olukwi-100°C kangangeentsuku ezingama-90 (80°C kulwelo olusekelwe emanzini) kwaye uluphinda uvavanyo rhoqo emva kweentsuku ezingama-30.Ngezantsi kukho iziphumo eziqhelekileyo, kodwa ukuqinisekiswa kuyacetyiswa kulwelo ngalunye.
Umzobo 3. Ukugcinwa kwe-ARI kwi-NBR kunye ne-hydrolysis-resistant polyurethane emva kokuguga kwioli ye-mineral distilled kwi-100 ° C.
Nangona iinkcukacha zibonisa ukuhambelana nolwelo olugqityiweyo, ukuvavanywa kokuguga okukhawulezayo (okanye iminyaka yenkonzo) kufuneka kunqume ukusebenza kwexesha elide kunye nokuzinza kwezinto ezivezwe kumanzi athile.Iimvavanyo zeSistim zeSistim zokuhambelana kolwelo lweentsuku ezingama-90 kunovavanyo oluqhelekileyo lweyure ye-168 ngenxa yokuba iiSistim zeSistim zihlala zibona utshintsho olubalulekileyo kwiipropathi zezinto eziphambili emva kweeyure ze-168 zokuvezwa kolwelo.
I-polyurethane eyenziwe ngokwezifiso ibonisa ukuxhathisa ulwelo oluphuculweyo xa kuthelekiswa ne-NBR kwezona zinto ziqhelekileyo zokuthambisa kushishino lwamandla omoya.Apha ngezantsi kukho itafile ehambelanayo kwezi zithambiso zidumileyo.
I-NBR yaziwa ukuba ichaphazeleka kwi-ozonolysis, kuxa iimolekyuli ze-ozone ziqhekeza iibhondi zemichiza kwi-NBR engaxutywanga.Ukuqhekeka kwe-ozone kuqhelekile xa irabha ye-nitrile butadiene (NBR) iphantsi koguquko oluncinci.Esinye isisombululo kukufaka i-wax kwi-NBR, ukudala umqobo ochasene ne-ozone okhusela i-NBR.Ngelishwa, i-wax ayitshintshi i-chemical bond ye-NBR.Ukuba i-NBR ibonakaliswe kwiimeko zokusingqongileyo ezisusa i-wax, iba sesichengeni sokwehla kwakhona.Ezinye iipolyurethanes ezikhethekileyo ezisetyenziswa kwiitywina zamandla omoya ngokwendalo ziyakwazi ukumelana ne-ozone.
I-elastic modulus, amandla kunye nobude be-polyurethane buphezulu ngokuphindwe kabini ukuya kathathu kunoninzi lwe-NBR.Ngenxa yoko, izitywina ze-polyurethane ziyakwazi ukumelana nokukhubazeka okukhulu koomatshini kunye nokumelana nemithwalo ephezulu yomatshini.
I-NBR eqhelekileyo ine-elastic modulus ye-10-15 MPa kunye namandla okuqina angama-20 MPa.Uninzi lwe-polyurethanes lune-elastic modulus ye-45-60 MPa kunye namandla okuqina angama-50-60 MPa.Oku kuthetha ukuba izinto eziphathekayo zincinci kune-NBR, oku kuthetha ukugcinwa kwemilo engcono kunye nokuchasana okukhulu kwimithwalo yoxinzelelo.
Kwii-injini zomoya, amaqondo obushushu aphezulu aqhelekanga ukuba yingxaki.Nangona kunjalo, kuxhomekeke kwindawo kunye nokuphakama, ubuncinane beqondo lokushisa -40 ° C aliqhelekanga.I-NBR eqhelekileyo inobushushu obusezantsi bokusebenza obuyi -20°C, kwaye uhlalutyo lomatshini oluguquguqukayo lubonise ukuba amandla omoya amaninzi e-polyurethanes awachatshazelwanga ngamaqondo obushushu ukuya kutsho kwi -40°C.
I-Polyurethane lukhetho lwendalo lwezitywina zamandla omoya ngenxa yeempawu zayo eziphezulu zemishini, ukuxhathisa okungcono kwe-ozone, amazinga aphantsi okugqoka kunye namaqondo okushisa aphantsi okusebenza.Ngezantsi kukho iintsapho ezimbini zezicelo apho i-polyurethane ifaneleka kakuhle.Umfanekiso osekhohlo ubonisa ukuguqulwa okufanisiweyo kunye neempawu zoqhagamshelwano zetywina elithwele i-polyurethane.Umfanekiso osekunene ubonisa iSystem Seals swirl seal, itywina eliphambili elisoloko limpompa i-lubricant ibuyele kwindawo yokugcina amanzi njengoko ibheri ijikeleza.
Ukuba ungathanda ukufaka isandla kwi-Windpower, nceda uqhagamshelane nathi: https://www.bdseals.com okanye www.bodiseals.com.I-NINGBO BODI SEALS CO., LTD ivelisa zonke iintlobo ezahlukeneyo zomgangatho ophezulu wetywina werabha,iioringi ,Iigaskets .
Ixesha lokuposa: Dec-24-2023