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Cdng trinh Khoa hpc NGHIEN CUtJ ANH HlTOTNG GAN VUOT KHI DAP TAO HINH CHI Tl£T HINH DANG PHlTC TAP VA MO PHONG B A N G PHAN MEM DYNAFORM 5.6 NGUYEN VAN Hl/CfiVG Khoa Cakhi Tru&ng Bgi hgc Giao thdng V^n ldi Tdm tdt: Gdn vudl ihudng dugc sir dgng qud trinh ddp vudt sdu, ddp cdc chi tiet cd hinh dgng phuc tgp cdc chi Hit cd phdn ddy ldi nhdm cdi thien ddng chdy ctia vgt lieu sudt qud trinh tgo hinh Viec xdc dinh vj tri, dgng hinh hpc ctia gdn vudt Id rdt cdn thiet vd thuang dira vdo kinh nghiem vd cdc nghien cuu thuc nghiim Hien nhd sir dung cdc phdn mem md phdng cho phep chiing ta cd the gidm thai gian thu khudn di dua cdc gid tri phii hpp nhdt ciia gdn vudt Bdi bdo dua cdc ket qud nghien ctru dnh hu&ng cua gdn vudt Irong hi thdng chgn vd md phdng bdng phdn mem Dynaform 5.6 cho chi Hit tdm chdn ngodt (tdm op) bau Ipc xe mdy Honda Lead Cdc kit qud ndy Id ca s& cho vigc lua chon cdc thdng so phii hgp de thiet ke khudn Summary: Draw beads are often used in the deep drawing, stampings with convex bottom, intricate shape stampings to improve control of the material flow during the forming process Geometry and location determination of the draw bead is essential and often based on experience and experimental research This paper presents the research results about the influence of the draw bead on the blank holder and simulated by Dynaform 5.6 for detailed Dynaform external shields (panels) air fillers in Honda Lead These results are the basis for selection of appropriate parameters for the mold design I G I O I T H I E U Khi dap cac chi ti6t hinh dang phiic tap n h u vd d td, tam dp tiang tri ciia xe may, cac chi tiet dang hinh hop, phdi tam bi keo vao tiong Idng cdi khdng deu nen gSy hiSn t u g n g nhan rach, Nghien ciiu qua trinh d a p vudt chi ti6t d a n g hop n g u d i ta thSy rang lv:c k e o phdi vao tiong cdi d nhiing vi tii khac cua d u d n g b a o k h d n g gidng [1] L u c keo phdi v a o tiong cdi d cac Hinh Cdi cd gdn vudt vd vi iri cita gdn vudl trin khudn a - Cdi cd gdn vudt di dgp cdc chi Hit hinh hpp, b-Vi tri cua gdn vudt tren khudn phan tiianh thSng nhd b a n so vdi luc keo d cac phSn cong D e cd the tao s u ddng deu t u a n g ddi ve dieu kien keo phdi vao ti-ong cdi tren loan bd d u d n g bao, d cac phiin th^ng n g u d i la lam tang tid luc keo phdi vao tiong cdi b a n g gan vudt Gan vudt d u g c d^t tiong cac ranh tien be mat cdi hoac vanh chan n h u thay ti-ong hinh Tap chi KHOA HQC GIAO THONG VAN TAI So dac biet - 11 /2015 151 Cdng trinh Khoa hpc II XAC DINH ANH Hl/OfNG CUA GAN VUOT LEN HE THONG CHAN VA CAC THONG SO HiNH HOC CUA GAN VUOT Anh hudng cua gan vudt tien he thdng chan cua khudn dugc danh gia thdng qua Ird luc keo ma nd tao Luc keo qua gan vudt phu thudc vao vat lieu phdi, chi8u day phdi, hinh dang gan vudt Md hinh xac dinh luc keo qua gan vudt nhu sau [4]: Theo hmh 2, luc keo phdi qua gan vudt Ihay ddl tir To dfin Tf a) b) Hinh Md hinh xdc dinh lgc keo phdi qua gdn vudl a) Md hinh xdc dinh lgc keo phdi qua gdn vudt; b) Su tdng trd luc keo Dg xac dinh Tf (N/m) ta chia qua Irinh keo phdi qua gan vudt giai doan tii A den B, tu B dgn C, tit C d6n D Qua mdi diem udn luc keo tang len mgt lugng AT, (N/m) (cdng thirc t,T„ 4TI P htell At, t, /^a chi6u day giam xudng [4]: (2.1) t,.T, (2.2) Trong dd: Ty, - Luc keo cin thiet cho sir chay deo cua tam dieu kien khdng cd md men nao tac dung (N/m); Ty, = kf 1, (cdng thiic 10.4 [4]); Ti - Luc keo tai di6m udn i (N/m); l, la chieu day phdi d diem udn i (m); kf - irng su4l chay cua vat Heu phdi (N/m^); p - ban kich gdc lugn cua hdc gan tren cdi (m); q, - mice dd biSn dang phu thudc vao vat lieu phdi Luc keo phdi bi udn d A, B, C, D: TfA = To+AT„ ;TfB-TB+ATB;Ta: = Tc+AT^;TfD = TD+ATo (2.3) Luc keo ma sat tii A dgn B: Tg == TfA e^" (cdng thiic 10.24 [4]) (2.4) Tuang tu luc keo ma sat tii B den C, C den D: Tc = T,B e^^^TD-Tfc e"' (2.5) Trong do: - gdc dm ciia gan vudt theo hinh 2; AT^, ATg, AT^, ATp: xac dinh theo (2.1) Luc keo phdi qua gan vudt Tf: Tf = TfD = Tfc e''" + AT^ (2.6) T, Jjk ±4i.[ j-Tiu ±^1 jj-iiu ±^umiV 111 ''I P U.tJJj 4ii p [ U f t J J j 4n p I M C J J J tn P [ Trong do: IB, tc ID dugc xac dinh theo (2.2), to - chieu day phdi ban dau Ur'JJ Theo [2] gdc dm gan vudt = 1,3 — (xem hinh 2, h- chieu cao gdn vudt w = —— ) w (2.8) Luc keo phdi chan phSng khdng gan vudt: To = PFN; F^ - Luc chan phdi Theo (2.7) ta thSy gan vudt lam tang luc keo phdi so vdi chan phang va lam giam chi6u day 152 Tap chi KHOA HOC GIAO THONG VAN TAI So dac biet - 11/2015 Cdng trinh Khoa hpc cua phoi tam Cac thdng sd hinh hgc cua gan vudl anh hudng den ti-d lire keo bao gdm chieu cao cua gan vudt h, ban kinh lugn cua gan r, chi^u rdng gan b, ban kich gdc lugn cua hdc gan tien cdi p Ngu bilt cac thdng sd hinh hgc cua gan vudt thi hoan loan tmh dugc luc keo phdi qua gan vudt theo cong thiic (2.7) va chidu day cua phdi qua gan vudt to (2.2) td se chgn dugc gan vudl phu hgp (tang luc keo tai vimg thang ciia dudng bao cdi ma vat lieu khdng bi bien mdng qua nhiSu) UI MO PHONG SO D £ XAC DINH ANH HUOfNG CUA GAN VUOT KHI DAP VUOT CHI TIET TAM OP BAU LOC KHi XE MAY HONDA LEAD Tac gia sd dung phSn mim Dynaform 5.6, mgt phSn mem ca ban dugc su dung hieu qua tiong vi?c phan tich bien dang ciia kim loai tam de tien hanh xac dinh anh hudng ciia gan vudt den qua trinh dap mdt chi tiet cu the la tam dp bau lgc xe may Honda LEAD 3.1 M6 hinh dung c^ va phoi Trong md hinh tien hinh thi chay diing yen Md hinh cdi chuyen ddng vdi mdt bac tu Iheo mdt hudng xac dinh ciia trgc z Md hinh cdi dugc su dung d6 tao cac phan cua khudn dap (cdi, chay, vanh chan bang each chep tii cdi) Cac diiu kien bien: - Vat heu tim SS409MD (thep khdng gi), chieu day phdi t = 0,35 mm, kich thudc phdi 220x390mm, kf = 240 (MPa) xem hinh 4, he sd ma sat ^ = 0,1; miic bien dang i\= - Tdc di chuyen cua cdi: chgn 400 (mm/s) theo [3], - Ap luc chan ri6ng q 4MPa chgn theo [I], td dd tinh dugc FN = 12 tan - Thdng sd hinh hgc cua gan vudt (2 logi bien dgng gdn vudt la hinh chir nhdt vd hinh tron nhu thdy tren hinh vd bdng 1) Nhu tren hinh ta dat gan vudt tiong vung tiiine cua dudng bao cdi Cac ° Hinh Md hinh chi del ddp vd khudn ddp vudt de md phdng a) Md hinh chi Hit ddp; b) Mo hinh khudn dap vudt de md phong Hinh Hinh dgng vd kich thir&c ciia gdn vudt chit nhdl vd gdn vudt iron Bdng Cdc kich ihu&c cua gdn vudt Loai gan vuot Bien dang iron BiSn dang cha nhat Chieu sau h 3,5 mm 3,5 mm Ban kinh loi vao p Ban kinh rSnh Khoang rgng ranh 2\v 1,5 mm 1,5 mm 1,5 mm 1,5 mm Tmm Goc luon ranh 7mm 55" Goc lugn !6i vao 55" 55° 55° f^'"'' S- Huang chdy cua vgt liju vdo long coi vd bd tri gdn vuot tren be mgl coi Tap ch! KHOA HQC GIAO THONG VAN TAI So flac biet - 11 /2015 153 Cdng trinh Khoa hpc gan vudt dugc dat song song vdi mep canh cdi Gan vudt sd dai 30 mm, sd dai 84 mm, sd dai 24 mm, sd dai 112 mm dugc thiet lap vao phan mdm 3.2 Tinh luc keo phdi tren don vi chieu dai gan vuot theo ly thuyet Xet vdi gan vudt sd 2, gan vudt cd bien dang hinh chii nhat dai I = 140 mm dya vao chifiu rdng vanh chan phdi la b = 35 mm Theo bang va (2.8) tinh dugc * -1,3 la tinh dugc luc keo phdi To tren mdt don vi chiSu pqb = 14 IcN/m Thay cac dieu kien bien vao (2.2), (2.7) la tinh dugc luc keo phdi qua gan vudt Tf ^ 50,82 kN/m va chi8u day phdi qua gan vudt tf = ID = 0,3 mm Nhu vay ed gan vudt thi luc keo phdi tang tii 14 (kN/m) d6n 50,82 kN/m va chilu day giam tir 0,35 nun xudng 0,3 mm 3.3 Ket qua mo phong 3.3.L Ket qud mo phdng qud trinh dap tgo hinh khong su- dfing gan vuot dai gan vudt la: T^ = pF^ = Tren hinh bieu dien k§t qua bidn mdng ciia san pham Ta thay vimg nguy hiem nhat tai gdc lugn cua day san pham, dieu dd cho thay nhiing vung dd rat de bi rdch neu luc chan tang day, la ciing nhan thay rat ro hau nhu tam kim loai d Hinh Phdn bd biin dgng vimg giiia cua san pham khdng bi vd chieu ddy phdi khdng sir dgng gdn vudt bien dang deo, ma chi bien dang dan hdi Vi vay sau tao hinh, tim se bi sai l^ch kich thudc bi6n dang dan hdi, 3.3.2 Ket qud mo phdng qud trinh dap tgo hinh cd su dgng gdn vudt b Phdn bd chieu ddy phdi Hinh Cdc kit qud mo phong vdi gdn vudl trdn 154 b, Phdn bd chiiu ddy phoi Hinh S Cdc kit qud mo phdng vdi gdn vudt chu nhgt Tap chi KHOA HOC GIAO THONG V^N TAI So dac biet - 11 /2015 Cdng trinh Khoa hpc c Phdn bd img sudl Hinh (Tiip) c Phdn bd irng sudt Hinh (TiipJ Qua md phdng cd bang sau: g Cdc ket qud md phong ddp vuot vdi gdn vuot trdn vd gdn vudl hinh cha nhd Chii nhat Tron Khong giin vuot U'ng suit Ion nhSt (MPa) 1920 1384 1375 Chieu day 16n nhat (mm) Chieu day nho nhat (mm) ChiSu day san phSm (nun) 0,37 0,1 0.27 0,38 0,2 0,292 0.38 0,06 0,1 Bien dang gan vuot Tinh toan Iy thuyet 0.35 03 03 3.4 Nhan xet Qua ket qua md phdng d hinh 7a, hinh 8a cho thay hinh dang chi tiet rd net ban vimg nhSn xuat hien it hon so vdi khdng sir dung gdn vudt Xem hinh 7b, hinh 8b la thay phan bd chieu day phdi ddng d6u han Chieu day san pham (0,27 mm va 0.292 mm) sai khac khdng nhieu vdi tinh loan ly thuy6t d muc 3.2 (0,3 mm) Nhu vay giiia tinh loan va kilm nghiem la kha phu hgp Bang ciing th£ hien cac ket qua dap vdi gan vudt bien dang hinh chii nhat cho iing suit Idn ban va chi6u day giam nhieu ban so vdi gan vudt hinh trdn Nhu vay trd luc keo phdi cua gan vudt trdn nhd ban gan vudt chii nhat IV KET LUAN B^i bao dS dua each tinh lire keo phdi qua gan vudt de tii dd lua chgn dugc cac thdng sd hinh hgc cua gan vudt phu hgp cho viec md phdng va thiet ke khudn Su dung phSn m6m Dynaform dl md phdng qua trinh biln dang cua chi tiet tim dp bau lgc xe may Honda Lead dS cho thiy: kit qua md phdng cua phin mem va tinh loan ly thuyet tuong ddi phii hgp; tao hinh cac chi tilt hinh dang phiic tap nen sii dung gan vudt he thdng chan dl chong nhan va rach cho san phim; gan vudt hmh chii nhat gay Ird Igc keo phdi nhieu han gSn vudt hinh tidn Ngay nhSn bai lan diiu: 24/9/2015 Ngay nhan bM sira: 4/10/2015 Ngiky chip nh^n dang bai: 1/10/2015 T&i lifu tham khao [1] Nguyin Mau DSng (2004), Cong nghe tao hinh ldm lop tSm, NXB Khoa hoc va kj thuat [2] Nguyin Ddc Trung, Trdn Thanh Tfiuy, Nghien cihi bi&i phap nang cao chit lirong san phim dap v6 to nha mo ph6ng s6 Tap chi Co Vi^t Nam, S6 6, thdng 6/2011 [31 ScWe/-Springer (1998), Metal Fonmng Handbook, Verlag Berlin Heidelberg [4] Z Maminiak, J.L Duncan, SJ Hu (2002), Mechanics of Sheet Metal Forming, Butterworth-Hememann An imprint of Elsevier Science Linacre House, Jordan Hill, Oxford 0X2 8DP 225 Wildwood Avenue, Wobum, MA 01801-2041 [51 KL Martrenco, Vo Tr an Khuc Nha bien dich (2005), S6 tay thiSt k6 khuon d?p tSm, NXB Hal Phong* Phan bien; Nguyen Mong Stfn, Nguyen VSa Ciroug TapchiKHOAHQCGIAOTHONGVANTAI So dac biet -11/2015 155 ... MO PHONG SO D £ XAC DINH ANH HUOfNG CUA GAN VUOT KHI DAP VUOT CHI TIET TAM OP BAU LOC KHi XE MAY HONDA LEAD Tac gia sd dung phSn mim Dynaform 5.6, mgt phSn mem ca ban dugc su dung hieu qua tiong... gdn vuot trdn vd gdn vudl hinh cha nhd Chii nhat Tron Khong giin vuot U''ng suit Ion nhSt (MPa) 1920 1384 1375 Chieu day 16n nhat (mm) Chieu day nho nhat (mm) ChiSu day san phSm (nun) 0,37 0,1 0.27... mdm 3.2 Tinh luc keo phdi tren don vi chieu dai gan vuot theo ly thuyet Xet vdi gan vudt sd 2, gan vudt cd bien dang hinh chii nhat dai I = 140 mm dya vao chifiu rdng vanh chan phdi la b = 35
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