PET (Polyethylene terephthalate)
Bushewa da Crystallizing kafin sarrafa allura gyare-gyare
Dole ne a bushe kafin a yi gyare-gyare. PET yana da matukar damuwa ga hydrolysis. Na'urar dumama iska ta al'ada ita ce 120-165 C (248-329 F) na awanni 4. Danshi abun ciki yakamata ya zama kasa da 0.02%.
Ɗauki tsarin ODEMADE IRD, lokacin bushewa yana buƙatar 15mins kawai. Ajiye farashin makamashi kusan 45-50%. Danshi abun ciki na iya zama 50-70ppm. (Zazzabi na bushewa, lokacin bushewa na iya zama daidaitacce ta buƙatun abokan ciniki akan kayan bushewa, duk tsarin ana sarrafa shi ta Siemens PLC). Kuma shi ne sarrafa tare da bushewa & Crystallizing a lokaci guda.
Narke zafin jiki
265-280 C (509-536 F) don maki marasa cika
275-290 C (527-554 F) don darajar ƙarfafa gilashi
Mold zafin jiki
80-120 C (176-248 F); Wurin da aka fi so: 100-110 C (212-230 F)
Material allura matsa lamba
30-130 MPa
Gudun allura
Babban gudun ba tare da haifar da embrittlement ba
Injin gyare-gyaren allura:
Ana amfani da gyare-gyaren allura musamman don haɓaka gyare-gyaren PET. Yawancin lokaci, PET na iya zama kawai ta injin gyare-gyaren allura.
Zai fi dacewa don zaɓar dunƙule mutant tare da zobe na baya a saman, wanda yana da babban taurin farfajiya da juriya, kuma yanayin yanayin ba L / D = (15 ~ 20): 1 matsawa rabo na 3: 1.
Abubuwan da ke da manyan L / D suna zama a cikin ganga na dogon lokaci, kuma zafi mai yawa na iya haifar da lalacewa kuma yana shafar aikin samfur. Matsakaicin matsawa ya yi ƙanƙanta don haifar da ƙarancin zafi, yana da sauƙin yin filastik, kuma yana da ƙarancin aiki. A gefe guda kuma, karyewar filayen gilashin zai kasance da yawa kuma za a rage kayan aikin injin ɗin. Lokacin da aka ƙarfafa fiber ɗin gilashin PET, bangon ciki na ganga yana sawa sosai, kuma ganga an yi shi da kayan da ba zai iya jurewa ba ko kuma an yi masa layi da kayan da ba zai iya jurewa ba.
Tun da bututun ƙarfe ya kasance gajere, bangon ciki yana buƙatar ƙasa kuma buɗewar ya kamata ya zama babba gwargwadon yiwuwa. Bututun ƙarfe na nau'in bawul ɗin birki na hydraulic yana da kyau. Ya kamata nozzles su kasance da matakan kariya da zafin jiki don tabbatar da cewa nozzles ba su daskare da toshewa. Koyaya, zafin bututun ƙarfe bai kamata ya yi girma ba, in ba haka ba zai haifar da gudu. Dole ne a yi amfani da ƙananan matsi na PP abu kuma a tsaftace ganga kafin fara farawa.
Babban yanayin gyaran allura na PET
1, zazzabin ganga.Matsakaicin zafin jiki na PET yana kunkuntar, kuma zafin jiki zai shafi aikin samfurin kai tsaye. Idan yawan zafin jiki ya yi ƙasa sosai, ba shi da kyau don yin filastik sassa na filastik, ƙwanƙwasa, da rashin lahani na kayan abu; akasin haka, idan yanayin zafi ya yi yawa, zai haifar da splashing, nozzles za su gudana, launi zai yi duhu, ƙarfin injin zai ragu, har ma da lalacewa zai faru. Gabaɗaya, ana sarrafa yawan zafin jiki na ganga a 240 zuwa 280 ° C, kuma fiber na gilashin da aka ƙarfafa PET zafin jiki shine 250 zuwa 290 ° C. Zazzabi na bututun ƙarfe bai kamata ya wuce 300 ° C ba, kuma yawan zafin jiki na bututun yana yawanci ƙasa. fiye da zafin ganga.
2, zafin jiki.Yanayin zafin jiki kai tsaye yana rinjayar yanayin sanyaya da crystallinity na narkewa, crystallinity ya bambanta, kuma kaddarorin sassan filastik ma sun bambanta. Yawancin lokaci, ana sarrafa yawan zafin jiki a 100 zuwa 140 ° C. Ana ba da shawarar ƙananan dabi'u yayin ƙirƙirar sassan filastik masu bakin bakin ciki. Lokacin ƙirƙirar sassan filastik masu kauri, ana ba da shawarar samun ƙimar girma.
3. Matsin allura.Narkewar PET ruwa ne kuma mai sauƙin samuwa. Yawancin lokaci, ana amfani da matsakaicin matsa lamba, matsa lamba shine 80 zuwa 140 MPa, kuma PET mai ƙarfafa fiber na gilashi yana da matsa lamba na 90 zuwa 150 MPa. Ya kamata a ƙayyade matsa lamba na allura ta la'akari da danko na PET, nau'i da adadin mai filler, wuri da girman ƙofar, siffar da girman ɓangaren filastik, zafin jiki na mold, da nau'in injin gyare-gyaren allura. .
Nawa kuka sani game da sarrafa robobin PET?
1, sarrafa robobi
Tunda PET macromolecules sun ƙunshi tushe mai lipid kuma suna da takamaiman hydrophilicity, barbashi suna kula da ruwa a yanayin zafi. Lokacin da abun ciki na danshi ya wuce iyaka, nauyin kwayoyin halitta na PET yana raguwa, kuma samfurin yana launin launi kuma ya zama mai laushi. A wannan yanayin, dole ne a bushe kayan kafin aiki. Yanayin bushewa shine 150 4 hours, yawanci 170 3 zuwa 4 hours. Ana amfani da hanyar jet ɗin iska don gwada ko kayan ya bushe gaba ɗaya.
2. Zaɓin na'urar gyare-gyaren allura
PET yana da ɗan gajeren lokacin narkewa da babban wurin narkewa, don haka dole ne a zaɓi tsarin allura tare da kewayon sarrafa zafin jiki mafi girma da ƙarancin dumama kai yayin yin filastik, kuma ainihin nauyin samfurin ba zai iya zama ƙasa da 2/3 na nauyinsa. Yawan allurar inji. Dangane da waɗannan buƙatun, a cikin 'yan shekarun nan, Ramada ya haɓaka jerin ƙanana da matsakaicin girman PET tsarin filastik na musamman. Ƙarfin matsawa da aka zaɓa ya fi 6300t / m2.
3. Mold da ƙirar kofa
PET preforms yawanci ana yin su ta hanyar ƙwararrun masu gudu masu zafi. Garkuwar zafi tsakanin ƙirar da injin gyare-gyaren allura ya fi dacewa a rufe tare da kauri na 12 mm, kuma garkuwar zafi na iya jure babban matsa lamba. Dole ne tashar shaye-shaye ta isa don guje wa zafi na gida ko guntuwa, amma zurfin tashar tasha yawanci baya wuce 0.03 mm, in ba haka ba walƙiya yana da sauƙi.
4. Narkewar zafin jiki
Ana iya yin ma'auni ta hanyar jirgin sama. A 270-295 ° C, ana iya saita matakin haɓakawa na GF-PET zuwa 290-315 ° C.
5. Gudun allura
Gudun allurar gabaɗaya yana da sauri sosai, wanda ke hana saurin warkewar allurar. Amma da sauri sosai, girman juzu'i yana sa kayan ya lalace. Yawanci za a kammala bugu a cikin daƙiƙa 4.
6, matsawar baya
Ƙananan mafi kyau, don kada a sawa. Gabaɗaya bai wuce 100 bar ba.
Lokacin aikawa: Fabrairu-24-2022