I-Polyurethaneigwebu eliqinileyoyenye yezona zinto zisetyenziswa kakhulu ekugqumeni ubushushu kwishishini lokukhenkceza. Ukususela kwiifriji zasekhaya kunye neefriji ukuya kwiindawo zokugcina izinto ezibandayo zorhwebo, i-polyurethane rigid foam inika ubushushu obuhle kakhulu, ukusebenza kakuhle kwamandla, kunye nokuqina.inkqubo yokuvelisa i-polyurethane rigid foamKubalulekile kubavelisi abafuna umgangatho ohambelanayo, kwaye inxalenye ephambili yale nkqubo kukukhetha ngokufanelekileyoiikhatalyst ze-polyurethane.
1. Izinto eziluhlaza kunye nokuQulunqwa
Ukuveliswa kwe-polyurethane rigid foam kwiifriji kuqala ngezinto ezikhethiweyo ngononophelo:
- IiPolyols– zisebenza njengezinto ezisisiseko, zichonga iipropati zefoam ezifana noxinano kunye namandla okucinezelwa.
- Ii-Isocyanates– ngesiqhelo i-polymeric MDI (pMDI), esabela kunye nee-polyols ukuze zenze iibhondi ze-urethane.
- Iiarhente zokuvuthela– njenge-pentane okanye ii-HFO ezinobuhlobo nokusingqongileyo, ezidala ulwakhiwo lweseli yefoam.
- Izongezo– kuquka izinto ezithintela ilangatye, izinto ezibangela ukuba izinto zingasebenzi kakuhle, kunye nezinto ezizinzisa umlilo.
- Iikhatalyst zePolyurethane– kubalulekile ekulawuleni ukwenzeka kwento esebenzayo kunye nesantya sokulungisa inkqubo.
2. Ukubaluleka kweePolyurethane Catalysts
Kwifriji, inkqubo yokukhupha amagwebu kufunekaizinzile, iyafana, kwaye iyalawulekaukuqinisekisa ukusebenza okulinganayo kokugquma kunye nozinzo olulinganayo.Iikhatalyst zePolyurethanezisetyenziselwa ukulinganisela impendulo phakathi kwe-isocyanate kunye ne-polyol (impendulo ye-urethane) kunye nempendulo ye-water-isocyanate (impendulo ye-urea).
Isetyenziswa rhoqoii-catalysts ze-amineziquka:
- I-Triethylenediamine (i-TEDA)– inika umsebenzi oqinileyo wokugaya ijeli, ikhawulezisa ukwakheka kwe-urethane, kwaye iqinisekisa ukuphiliswa kakuhle kwefoam.
- I-Pentamethyldiethylenetriamine (PMDETA)– ilungelelanisa ukusabela kwe-foam kunye ne-gelling, iqinisekisa ulwakhiwo olufanayo lweseli.
- I-Dimorpholine diethyl ether (i-DMDEE)– inika ukuphinda-phinda okulibazisekileyo, yandisa ixesha lokhilimu kwaye iphucula ulawulo lwenkqubo.
Iikhatalyst zesinyithi, njenge-stannous octoate okanye i-dibutyltin dilaurate, zisetyenziswa kunye nee-amine catalysts ukuphucula ngakumbi ukunyanga nokufezekisa ixesha elifunekayo lokungasebenzisi i-tack.
Ukukhetha indibaniselwano efanelekileyoii-amine kunye nee-catalysts zesinyithiinokuthi:
- Lawula iprofayili yokunyuka kwefoam.
- Thintela ukuqhekeka nokuqhekeka kwesikhumba ngexesha lokukhupha igwebu.
- Fumana ukunamathela okuhle kakhulu eludongeni lwekhabhathi yefriji.
- Lungiselela amaxesha omjikelo kwimigca yemveliso eqhubekayo nengaqhubekiyo.
3. Ukuxuba kunye nokuMitha
Ukuveliswa kwefoam efrijini, ngokuchanekileyoizixhobo zokulinganisaixuba i-polyol, i-isocyanate, i-blowing agent, i-surfactant, i-flame retardant, kunye nee-catalysts kwi-ratio echanekileyo. Nakuphi na ukuphambuka kunokubangela utshintsho loxinano, ukunamathela okungekho semgangathweni, okanye ukushwabana.
Ezi zinto zixutyiweyo zifakwa kwikhabhathi yefriji okanye kwisikhunta somnyango. Kule ndawo,impendulo ye-polyurethaneziqala ngoko nangoko, kwaye ii-catalysts zidlala indima yazo ekulawuleni ixesha lekhrimu, ixesha lokuvuka, kunye neprofayili yokuphilisa.
4. Ukukhupha igwebu kunye nokunyanga
Ngexeshainqanaba lokufutha, i-agent yokuvuthela iyakhula kwaye idale isakhiwo esincinci nesivaliweyo seeseli. Ii-catalysts ze-amine zilawula isantya sokuphuma kwegwebu, ngelixa ii-catalysts zesinyithi zikhuthaza ukudibanisa okunqamlezileyo, okukhokelela kwigwebu eliqinileyo neliqinileyo.
Efanelekileyoukhetho lwekhataystaliiqinisekisa ukuba:
- Igwebu liyakhula ngokulinganayo ukuze lizalise wonke umngxuma.
- Ifoam inamathela kakuhle kwisinyithi, iplastiki, okanye kwiindawo ezidityanisiweyo.
- Ifoam yokugqibela ine-insulation egqwesileyo yobushushu (ixabiso eliphantsi le-λ) kunye namandla oomatshini.
5. Ulawulo loMgangatho kunye noVavanyo lokuSebenza
Emva kokunyangwa, i-foam yefriji iyavavanywa ku:
- Ubuninzi kunye nolwakhiwo lweseli
- Amandla okuncamathela
- Ukuqhuba kobushushu
- Uzinzo lwemilinganiselo
Ulawulo lomgangatho oluqhubekayo luqinisekisa ukuba iifriji zifikelela kumanqanaba azo okusebenzisa amandla ngendlela efanelekileyo.
Isiphelo
Iinkqubo yokuvelisa i-polyurethane rigid foam kwiifrijiixhomekeke kakhulu ekukhetheni ngokuchanekileyo nasekudibaniseniiikhatalyst ze-polyurethaneUkusebenzisa ii-amine catalysts ezifana ne-triethylenediamine, i-pentamethyldiethylenetriamine, kunye ne-dimorpholine diethyl ether—kunye nee-metal catalysts—kuvumela abavelisi ukuba bafezekise inkqubo yokufutha ezinzileyo, ukuphuculwa kwesakhiwo seseli, kunye nesantya sokuphilisa esiphuculiweyo.
Izinto ezintsha zeMingxu zigxile ekuboneleleni ngeenkonzo zokusebenza eziphezuluiikhatalyst ze-polyurethanekwiinkqubo zefoam zefriji. Uluhlu lwethu lwee-amine kunye nee-catalysts zesinyithi zinokunceda abavelisi ukuphucula ukusebenza kakuhle kwenkqubo, ukunciphisa iziphene, kunye nokuhlangabezana neemfuno ezifunekayo zokufakelwa kwe-friji yanamhlanje.
Ixesha leposi: Sep-17-2025