Tap Chi Khoa Hpc Gido Due Ky Thupt (33/2015) Trudng Dpi Hpc SuPhpm Ky Thuat TP Hd ChiMinh PHAN TICH GIA NHIET VA LAM NGUQI BANG NtTOC TRONG KHUON EP PHUN MOT SO SAN P H A M KHAC NHAU ANALYZE HEATING AND COOLING BY WATER IN INJECTION MOLDING PROCESS FOR DIFFERENT PRODUCTS Huynh D Song Toan, Tran Minh The Uygn V6 Bi Anh Dai, Le Hieu Giang Tru&ng Bgi hgc Su Phgm Ky Thudt TP.HCM Ngayteasom nhin bii 24/3/201S, ngdy phan bien dinh gii 30/3/201S, ngiy chip nhin dang 3/4/201S TOM TAT Hien nay, tren thi gi&i vd nu&c da co nhieu cdng trinh nghien ciru tdi uu hda nhiet d khudn Tuy nhien, viec phdn tich gia nhiet vd ldm ngudi bdng nu&c khudn ep nhua chua duoc thicc hien nhiiu tren cdc sdn phdm thuc ti Kit qud dat duac cita bdi bdo Id hodn thdnh viec md phdng truyin nhiet khudn ep nhua sir dung he thdng nu&c de gia nhiet va ldm ngudi long khudn Phucmg phdp gia nhiet bdng nu&c ndng cd the ndng nhiet khudn tir 3(!fC din 63.5'C 20 s, sau do, khudn duac gidi nhiet den 35°C th&i gian 20 s tiip theo Sau tien hdnh ddnh gid sai sd vd cdch hgn che sai sd thirc hien md phdng; phdn tich truyen nhiet khudn mdt sd sdn phdm khdc Tir khda: khudn nhua ep phun, he thdng ldm mdt bdng nu&c, sir tmyen nhiet ABSTRACT Currently, there are many research results to optimize the mold temperature However, t analysis of heating and cooling by water injection molding is not yet enough for reference The outcomes of this paper include a complete analysis of heat transfer in plastic injection molds using water for heating and cooling This method is able to increase the mold temperature from 3ff'C to 63.5°C in 20 s for the heating step and decrease the mold temperature to SS^C in the next 20 sfor the cooling step Also, the errors when performing simulation are examined Finally, the analysis of heat transfer in moldfor different products is performed Keywords: plastic injection molding, water cooling system, heat transfer GIOI THIEU NghiSn ciiu vl nhiet dp khuon tap trung vao nhiet dp nhua nong chay (melt temperature) va nhiet dp khuon (mold temperature) Trong do, nhiet dp nhua nong chay thuong duoc nha san xuit qui dinh nSn IJ thdng s6 rit kho thay dai [ ] Thay vao do, nhiet d5 khuon la ylu t l anh huong den:dp co rut va ling suit du cua san phim [2], dong chay nhua dien vao long khuon [3,4] va qua trinh giai nhiet cho san phim [5-7] Trong qua trinh xac dinh cac thong so phun ep, gia Ui nhiet dp khupn fliuong dupe nha san xuit vat lieu nhua qui dinhti:ongkhoang nhiet cho phep Tuy nhien, khac voi nhiet dp nhua nong chay, nhiet dp khuon co thi dupe phan thinh hai thoi dilm khac nhau: nhiet dp khuon Ichi nhua chay vao long khuon (Filling step) va nhiet dp khuon sau nhua da diln diy long khu5n (fiill fill) Nlu B-ong qua trinh nhua diln diy long khuon, nhiet d6 khuon cang cao (nhung phai thip hon nhiet dp nhua - melt temperahue) thi qua trinh Tgp Chi Khoa Hgc Gido Due Ky Thugt (33/2015) Tru&ng Dgi Hgc SuPhgm Ky Thugt TR H6 ChiMinh didn ddy long khudn cdng di, va nhidu Igi ich khac cd thd dgt dugc nhu: irng sudt du tten sdn pham thdp, dd chinh xdc vi kich thudc va hinh dang cang cao [8] Niu ttong qua trinh sau nhua da diin ddy Idng khudn, nhiet dp khudn cang thdp, qua trinh gidi nhiet cho san phdm s6 cdng thuan lpi ban, vd ket qua la cong venh cfta sdn phdm se giam ddng ki [8] Tuy nhien vide phan tich gia nhiet va lam ngudi bdng nude ttong khuon ep phun chua dugc thyc hien nhieu tten cde sdn pham khdc THIET KE CHE T^O B O KHUON THV*C NGHIDM 2.1 Thiet ke va md phdng tam khudn Thiet ke tdm khudn vdi dudng nude kiiu baffle nhu hinh Tien hanh phan tich md phdng dudng nude vdo khudn theo hinh Ket qua md phdng nhiet dudng nude dugc the hien d hinh Va ket qua nhiet dp be mat khudn ttinh bay ttong hinh BeieiOa' I I I I I 6B05e+001 B 477e+0D1 3496+001 23164001 093emD1 9B5e+0a' a37e+OQ' ' • 709e»O0' Hinh 3: Ket qud mo phong nhiet duang Te