Plastic extruder zvimedu zvepakati zvemidziyo muindasitiri yekugadzira mapurasitiki, inoshandiswa zvakanyanya mukugadzira zvigadzirwa zvakaita sepombi, maprofile, mafirimu, uye waya nematambo ekuvhara. Maitirwo acho anosanganisira matanho akawanda, anosanganisira kugadzira, kudziyisa nekunyunguduka, kuisa purasitiki nekuburitsa, kuumba nekutonhodza, nekugadzirisa-pashure. Nhanho imwe neimwe ine simba guru pahutano hwechigadzirwa chekupedzisira. Ichi chinyorwa chinotsanangura zvakarongeka maitiro ekuyerera uye akakosha ehunyanzvi mapoinzi epurasitiki extruder.
1. Raw Material Kugadzirira uye Pretreatment
Nhanho yekutanga mune epurasitiki extrusion process ndeyekuongorora uye pretreatment yezvakagadzirwa. Zvichienderana nezvinodiwa zvechigadzirwa, iyo mbishi inogona kuve imwe resin (senge polyethylene (PE) kana polypropylene (PP)) kana inoumbwa inoumbwa yezvakawanda zvinhu (sezviya zvine calcium carbonate fillers kana masterbatches). Raw materials inofanira kusangana nezvinodiwa zvinotevera:
Kuchena: Dzivisa kusvibiswa netsvina (senge simbi zvidimbu uye mapepa akaraswa), izvo zvinogona kukonzera kukuvara kwemidziyo kana kukanganisa kwechigadzirwa.
Kuoma: Hygroscopic zvinhu (zvakadai senaironi PA uye polycarbonate PC) inofanira kuomeswa muomesi pa80-120 dhigirii kwemaawa akati wandei kudzivirira mabhubhu panguva yekuburitsa.
Mixing Uniformity: Kana magadzirirwo acho aine zvinowedzerwa, premix the masterbatch kana zvimwe zvinowedzera mune-speed mixer kuti uone kupararira kwakafanana.
II. Kudyisa uye Kuendesa Danho
Pretreated raw materials inopinda muextruder barrel kuburikidza nehopper. Maextruder emazuva ano anowanzo kuve akashongedzerwa nekumanikidzwa feeder kana vibrating feeder kuti ive nechokwadi chinoenderera uye chakagadzikana chekudya. Zviitiko zvakakosha panguva iyi zvinosanganisira:
Feed Rate Matching: Izvi zvinofanirwa kurongeka pamwe nekumhanyisa screw uye kunyungudika kukwanisa kudzivirira kuunganidzwa kwezvinhu kana kunyura mudhiramu.
Anti-Bridging Design: Mudhuri wemukati wehopper unowanzo dhindwa kana kuiswa neagitator kudzivirira bhiriji nekuvharika nekuda kwekushaikwa kwemvura.
III. Kupisa, kunyunguduka, uye Plasticization
Mushure mekunge zvigadzirwa zvapinda mudhiramu, zvishoma nezvishoma zvinonyungudutswa uye kugadzirwa nepurasitiki neyakasanganiswa chiito che screw rotation uye kupisa kwekunze. Iyi nzira yakakamurwa kuita nzvimbo nhatu dzinoshanda:
Kuendesa Chikamu (Kudyisa Chikamu): Iyo screw inotenderera nekumhanya kwakaderera, ichisundira zvinhu mberi. Iyo tembiricha yedhiramu yakaderera (kazhinji 80-120 dhigirii) kudzivirira kunyungudika nguva isati yakwana.
Compression Section (Section Melting): Iyo tembiricha yebhari inowedzerwa zvishoma nezvishoma kusvika pamusoro pekunyungudika kwepurasitiki (semuenzaniso, ingangoita 160-180℃yePE). Iyo screw groove kudzika inodzikira, ichiwedzera kugera masimba uye kushandura yakasimba zvimedu kuita viscous melt.
Metering Chikamu (Homogenization Chikamu): Tembiricha inochengetedzwa nguva dzose (zvishoma pamusoro penzvimbo yekunyungudika), uye screw inoshanda nekumhanya kukuru kuti ive nechokwadi chekugadzikana kunyungudika kunyungudika uye kuumbwa kweyunifomu.
Makiyi tekinoroji paramita: Barrel tembiricha gradient, screw speed (kazhinji 50-300 rpm), uye melt pressure (5-20 MPa) inoda kugadziridzwa zvinoenderana nemidziyo. Semuenzaniso, kugadzirisa kwePVC kunoda tembiricha yakaderera (150-180 dhigirii) kudzivirira kuora kwekupisa.
IV. Extrusion uye Kufa Kuumba
Plasticized melt inoburitswa nemumusoro kuti iite muchinjiko unodiwa-sectional shape (senge machubhu eraundi kana rectangular profiles). Die dhizaini inobata zvakananga kunaka kwechigadzirwa uye inofanirwa kuita zvinotevera zvinodiwa:
Flow chiteshi chiyero: Inovimbisa yunifomu kudzvanywa munzira dzese mhiri kwekunyungudika kudzivirira kuzara kwenzvimbo kana kudzvinyirira.
Kudzora tembiricha: Tembiricha yekufa inowanzodzikira zvishoma pane tembiricha yebhari kutsiva kupera kwekupisa uye kuchengetedza fluidity.
V. Kutonhodza uye Kudhirowa
Iyo inopisa extruded melt inofanira kukurumidza kutonhora uye kuumbwa. Nzira dzakajairika dzinosanganisira:
Kutonhodza mvura: Izvi zvinowanikwa nekunyudzwa mutangi remvura kana kuti spray system (semumitsetse yekugadzira pombi). Kupisa kwemvura inotonhorera kunofanira kugadziriswa zvichienderana nechinhu (kazhinji 15-40 degree).
Kutonhodza mhepo: Inokodzera mafirimu matete kana zvigadzirwa zvitete -nemadziro, uchishandisa feni kana kuti chill rolls kuderedza tembiricha.
Zvichakadaro, muchina wekudhirowa unodhonza chigadzirwa nekumhanyisa nguva dzose kuti ive nechokwadi chekugadzikana kwedimensional. Huyero hwekudhirowa kumhanya kune extrusion kumhanya (dhirowa reshiyo) inosarudza density yechigadzirwa uye chimiro chemuviri.
VI. Kucheka neKutumira{1}}Kugadzira
Mushure mekutonhodzwa, chigadzirwa chinochekwa kuita zvikamu (semuenzaniso, 6-mita machubhu) kana kukuvadzwa kuita rolls (semuenzaniso, mafirimu, waya, uye tambo) uchishandisa online cutter. Zvimwe zvigadzirwa zvinoda kumwe kugadziridzwa, senge:
Kurapa kwepamusoro: Kurapa kwemoto kana kurapwa kwekorona kuti uwedzere kunamatira kudhinda;
Kuongorora Hunhu: Kutarisisa kukora kwemadziro kufanana uchishandisa infrared ukobvu geji kana kuongorora kwekuona kwehurema hwepasi.
Iyo yepurasitiki extrusion process inosanganisa multidisciplinary hunyanzvi (polymer zvinhu sainzi, mechanic engineering, uye thermodynamics). Kugonesa ma paramita padanho rega rega (semuenzaniso, tembiricha mbiri uye screw kumisikidza) inogona kuvandudza zvakanyanya kugadzirwa kwakanaka uye kunaka kwechigadzirwa. Nekufambira mberi kwehunyanzvi hwekugadzira tekinoroji, michina yemazuva ano yekuwedzeredza yakabatanidza masisitimu chaiwo-ekutarisa nguva uye otomatiki maitiro emhinduro, zvichienderera mberi kufambisa indasitiri yekugadzira mapurasitiki kuenda kune-mazvo uye maitiro anoenderana nenharaunda.
