Zotsatirazi ndi mfundo zofunika kukumbukira zokhudza extrusion.Ayenera kuthandiza kusunga ndalama, kutulutsa zinthu zabwino kwambiri, komanso kugwiritsa ntchito zida mwaluso.
1. Mfundo yamakina.Makina oyambira a extrusion ndi osavuta - screw imatembenuza mbiya ndikukankhira pulasitiki patsogolo.Zomangira kwenikweni ndi ndege yopendekeka, kapena njira yozungulira, yozungulira pakati.Cholinga chake ndi kuchulukitsa mphamvu kuti kukana kwakukulu kugonjetsedwe.Pankhani ya extruder, pali zotsutsana zitatu zomwe zingagonjetse: kusisita kwa tinthu tating'onoting'ono (chakudya) pakhoma la mbiya ndi wina ndi mnzake mumayendedwe angapo oyamba a wononga (malo odyetsa);kumamatira kwa kusungunuka kwa khoma la mbiya;ndi kukana kuyenda mkati mwa kusungunuka pamene kukankhidwira patsogolo.
Sir Isaac Newton anafotokoza-ed kuti ngati chinthu sichikuyenda m'njira yoperekedwa, mphamvu zomwe zili pa izo zimakhala zoyenera.Chophimbacho sichimasuntha molunjika, ngakhale kuti chikhoza kutembenukira mofulumira kudutsa mozungulira mozungulira.Chifukwa chake, mphamvu za axial pa wononga ndizoyenera, ndipo ngati zikukankhira kutsogolo ndi mphamvu yayikulu pa pulasitiki yosungunula ziyenera kukhala zikukankhira chammbuyo pa chinachake ndi mphamvu yofanana.Pamenepa, ikukankhira kumbuyo kwa chakudya chotchedwa thrust bear.
Zomangira zing'onozing'ono zambiri zimakhala kumanja, monga zomangira ndi mabawuti zomwe zimagwiritsidwa ntchito popala matabwa ndi makina.Amatembenuka motsatana ndi wotchi, ngati awonedwa kumbuyo, pamene akuyesera kudzigwetsera kumbuyo ku mbiya.Ena amapasa - screw extruders, zomangira ziwiri kutembenukira mbali zosiyana mu mbiya wapawiri ndi intermesh, kotero kuti wina ayenera kumanja -dzanja ndi lamanzere.Mu zina intermeshing mapasa - zomangira, zonse zomangira amatembenukira mbali imodzi choncho ayenera kukhala ndi lolunjika chimodzimodzi.Komabe, m'zochitika zonse, pali zokakamiza kuti zibwerere m'mbuyo, ndipo mfundo ya Newton ikugwirabe ntchito.
2. Thermal principle.Mapulasitiki otuluka ndi thermoplastics-amasungunuka akatenthedwa ndikukhalanso olimba akazizira.Kodi kutentha kosungunula mapulasitiki kumachokera kuti?Kutentha koyambira ndi mbiya / kufa kumatha kuthandizira, ndipo ndikofunikira kwambiri poyambitsa, koma kulowetsa mphamvu zamagalimoto - kutentha kwapang'onopang'ono komwe kumapangidwa mkati mwa mbiya pamene injiniyo imatembenuza wononga motsutsana ndi kukana kwa viscous kusungunuka - ndiye gwero lofunika kwambiri la kutentha. kwa onse kupatula makina ang'onoang'ono, zomangira zoyenda pang'onopang'ono, mapulasitiki osungunuka kwambiri -otentha kwambiri, ndi zopangira zokutira.
Pazinthu zina zonse, ndikofunikira kuzindikira kuti zowotchera mbiya sizomwe zimayambira kutentha panthawi yogwira ntchito, choncho zimakhala ndi zotsatira zochepa pa extrusion kuposa momwe tingayembekezere.Kutentha kwa mbiya yakumbuyo kungakhale kofunikira chifukwa kumakhudza kuluma, kapena kuchuluka kwa zolimba zomwe zimaperekedwa muzakudya.Kutentha kwa mutu ndi kutentha kumayenera kukhala pafupi kapena pafupi ndi kutentha komwe kumasungunuka, pokhapokha ngati atagwiritsidwa ntchito pazifukwa zina monga gloss, kagawane, kapena kuwongolera mphamvu.
3. The kuchepetsa liwiro mfundo.Mu extruders ambiri, wononga liwiro amasinthidwa ndi kusintha galimoto liwiro.Ma motors nthawi zambiri amatembenuka mozungulira 1750 rpm pa liwiro lathunthu, koma izi zimathamanga kwambiri pa screw ya extruder.Ngati itatembenuzidwa mofulumira choncho, imatulutsa kutentha kochuluka kwambiri, ndipo nthawi yokhalamo ya pulasitiki ikanakhala yaifupi kwambiri kuti ikonzekere yunifolomu yosungunuka bwino.Chiŵerengero chochepetsera chiri pakati pa 10:1 ndi 20:1.Gawo loyamba litha kugwiritsa ntchito magiya kapena pulley seti, koma gawo lachiwiri nthawi zonse limagwiritsa ntchito magiya ndipo zomangira zimayikidwa pakati pa zida zomaliza, zazikulu.
M'makina ochepa oyenda pang'onopang'ono (monga mapasa a UPVC), pangakhale magawo atatu ochepetsera, ndipo liwiro lapamwamba litha kukhala lotsika mpaka 30 rpm kapena kuchepera (ndi ma ratios mpaka 60: 1).Kumbali inanso, mapasa ena aatali kwambiri omwe amagwiritsidwa ntchito pophatikizana amatha kuthamanga pa 600 rpm kapena kupitilira apo, kotero kuti kuchepa kwapang'onopang'ono kumafunika, komanso kuzizira kwambiri.
Nthawi zina chiŵerengero chochepetsera sichimafanana ndi ntchito-pali mphamvu yopita yosagwiritsidwa ntchito-ndipo n'zotheka kuwonjezera ma pulleys pakati pa galimoto ndi gawo loyamba lochepetsera kuti musinthe liwiro lapamwamba.Izi mwina zimawonjezera liwiro la screw kupitilira malire am'mbuyomu kapena zimachepetsa liwiro lapamwamba kuti pulogalamuyo iziyenda pamlingo wokulirapo wa liwiro lapamwambalo.Izi zimawonjezera mphamvu zomwe zilipo, zimachepetsa amperage, ndikupewa zovuta zamagalimoto.Muzochitika zonsezi, kutulutsa kungaonjezeke, kutengera zakuthupi ndi zosowa zake zoziziritsa.
Nthawi yotumiza: May-04-2017