Thông tin tài liệu
NGHIEN CLfU-TRAO 06l NGHieN CLFU QUAN HE GIU'A LUC KICH DONG VO'I QUI OAO CHUYiN DONG C O A HAT VAT LIEU TREN MAY SANG RUNG C6 HUONG RESEARCH ON RELATIONSHIPS BETWEEN THE VIBRATING FORCE AND TRAJECTORY OF THE ]VL\TERIAL PARTILE ON THE VIBRATING SCREEN DIRECTION TS Nguyen Viit Tan Hgc vifin Ky thuat Quan su TOM TAT Tren ca sa nguyen ly hoat dgng cua mdy sdng rung cd huang, bdi bdo xdc dinh dnh huang Clia luc kich dgng vdo hop sdng den su chuyen dgng cua hat vdt lieu tren mat sdng nhdm xdc dinh moi lien he giira luc kich dgng vai quTdqo chuyen dgng cua hat vdt lieu de ddm bdo dieu Men ndng sudt vd hieu qud sdng hap ly nhdt Kit qud nghien cuu Id ca sa de gidi bdi todn lua chgn thong so kit cdu vd hinh hgc hgp ly cua mdy sdng theo dieu kien hat vat lieu Tix khoa: Li^c kich dgng, chuyen dgng, hat vdt lieu, sdng rung co huang ABSTRACT Based on the working principle of vibrating screen direction, this paper presents the correlations between vibrating force and the motion of material objects on the screen meshes to Determine the relationship between the vibrating force and the trajectory ofthe material particle to ensure the most efficient and efficient screening efficiency The results of this work provide the knowledge to solve the problem of selecting structural parameters and the rational geometry ofthe sieve under the conditions of the particle Keywords: Vibrating force, motion, material particles, vibrating screen direction DAT V A N D E May sang dugc su dyng phan loai vat lifiu xay dung, frong may sang rung co huong dugc sudung kha phd bifin CO rdt nhifiu uu viet so vdi cac loai may sang khac Loai may co mat sang nam ngang nen kich thuac nho gpn so vai cac loai khac cung nang suat May sang rung co huong lam vific theo nguyfin ly su dung Iyc kich dgng cua cap khoi lech tam tac dgng len hop sang, tao nang lugng cung cip cho cac hat vat lieu ndm yfin mat sang chuyen dgng lien tuc theo dang ban len- roi xuong va difin qua trinh phan loai vat lieu '^ ISSN 0866 - 7056 TAP CHi CO KHi VlfiT NAM, S6 nam 2017 NGHIEN CU'U-TRAO06l Theo [1], [2] va [3], nghifin cuu ly thuyfit va thyc tifin vfi may sang mng co huang cho thdy lyc kich dgng Ifin hop sang anh huong tiTJC tifip tai van tfie ban dau va quy dao chuyen dgng cua hat vat lieu, dieu lien quan den xac sudt Igt lo sang cua hat vat lieu va s6 lan tifip xiic Clia hat vat lieu vai mat sang Lyc kich dpng phy thugc vao mgt so thong so cua cum gay rung nhu khoi lugng khoi Ifich tam, ban kinh lech tam va so vong quay cua true Ifich tam Do do, ngi dung cua bai bao trinh bay co so khoa hgc ve m6i quan he giiia luc kich dpng voi qui dao chuyen dgng ciia hat vat lieu tren mat sang thong qua van toe ban dau, nham dat dugc hifiu qua sang la cao nhat Uong qua trinh phan loai vat Ueu QUI BJyO CHUYEN DQNG CUA HAT VAT LIEU TREN MAT SANG De xay dyng mo hinh dgng lyc hgc ciia may sang mng c6 huang, can mgt so gia thiet sau nhu: Coi Vi khoi lugng vat lieu trfin mat sang dao dgng cung voi hop sang; Hop sang dao dgng c6 huang theo dudng tac dung cua lyc kich dgng di qua trgng tam cua hop sang; Dp cung cua cac 16 xo dugc coi la nhu va qui ve cung tuong duong la C; Su dap tat dao dpng Clia hop sang dugc thfi hien bang he so dap tat dao dpng b; Bo qua sy ton hao ma sat tai cac khop cua cac chong Tu mo hinh vat ly may sang mng co huong va voi cac gia thiet, mo hinh tinh toan dpng lyc hgc cho theo hinh Trfin hop sang dat hai he true tga dp: He trye co dinh XOY co goc tga tning voi khoi tam cua hpp sang o vi tri can bang tTnh va co phuong ciia true X trung voi phuong dao dgng cua hfip sang, he true di dfing X'O'Y' Mo hinh dao dgng cua may sang mng co huong la mo hinh bac ty ling vai mpt tpa dp suy rgng x •Ir Hinh Md hinh linh todn ddng lifc hpc may sang rung CO hudng Trfin hinh 1, m^ la tong khoi lugng cua kh6i lech tam; co la van toe goc cua true lech tam; a la goc lyc kich dgng vai phuang ngang; P la lyc kich dgng tao boi cac khoi lech tam Gpi m la khdi lugng dao dgng ciia hop sang va vat lieu, theo [1] ta c6: m = m^^4-m^/3 voi m^ la khoi lugng hop sang, m^, la khoi lugng vat lieu trfin mat sang Tu mo hinh theo hinh 1, su dung phuong trinh Lagrang loai hai c6 dang tong quat: ar dt dx dx dx (1) dx Bdng viec xac dinh dugc dpng nang, the nang, ham hao tan va luc suy rpng ciia may sang, thay vao phuong trinh (1), phuong hinh vi phan mo ta chuyen dgng ciia hop sang la: (m -1- mg)x -i-bx + cx = mf,rgCO^ cos{cot) (2) Hay: X+ b X+ c m^j-.o)^ X ^ —'^— , ^, cos(faO (X[ K^) m + m^ m + m^ m + m,^ Voi difiu kien ddu: x(0)=0;.x(0) =0 Khi giai phucmg trinh (3), ung vcri bo s6 lieu cho traoc vfi kfit cdu (khoi lugng hop sang, vat lieu trfin mat sang, khoi lech tam, ISSN 0866-7056 TAP CHi CO KHi VIET NAM, S6 nam 2017 AVivw cnlrhivifitii'im v n ^ ST NGHIEN CU'U-TRAO OOl Cling 16 xo, ), kfit qua nhan dugc la bifin dO, van toe va gia toe dao dfing ciia hop sang Cac gia trj se anh huong true tifip dfin qui dao chuyfin dgng ciia hat vat lieu, ngi dung dugc xet a phdn dudi day Trong qua trinh lam viec, hop sang dao dgng, cac hat vat lieu dugc bdn Ifin- rai xuong CO qui dao chuyen dgng la mgt duang pa bon nhu hinh Nfiu bo qua qua trinh tmgt Clia hat vat lieu trfin mat sang, van t6c ban dau Vg Clia hat vat lieu c6 thfi coi diing bdng van toe dao dgng cua hop sang Thay x=x, va lay y=h (voi h la chifiu cao ban lfin ciia hat vat lieu) do: ^^v^sinV (7) Theo [1], thuong chgn y = 35", ta = 7,72^/A (8) Theo [1], quan he hgp ly giiia chieu cao h va kich thudc Id sang la: ft > 0,4/ (9) Nfiu cho tmdc kich thudc thi gia tri ly thuyfit hgp ly cua \^ dugc xac dinh phai thoai man theo cong thiic (8) va (9) Mat khac, neu coi VQ - i , x dugc xac dinh phuong trinh dgng lyc hgc may sang rung co hudng (3) thi vific thay doi gia trj lyc kich dgng Hinh 2: Qui dgo chuyen dgng cua hgt vgt lieu Khi do, phuong trinh mo ta qui dao chuyen dpng cua hat vat lieu nhu sau: (4) I JC = v^t c o s y Trong do: x, y la tga d6 cua hat vat lieu; v^ la tdc ban dau ciia hat vat lifiu,(m/s); la goc giira huang dao dgng ciia hop sang so voi phuang ngang, (do); Tir he phuong trinh (4) ta c6: 2v„.cos ;' (5) Ham (5) se dat cue dai x=x,: vltgycos^r (6) Pkd ^ '"o^^^ (thdng qua thay ddi khdi lugng hoac ban kinh lech tam) ma vdn giu nguyfin cac tham sd nhu b, C, m se lam thay ddi gia tri ban dau v^ va se tao cac quT dao chuyfin dgng khac nhau, nghia la co mdi quan he giira luc kich ddng va quT dao chuyfin ciia hat vat lieu, difiu se dugc lam ro ph&n dudi day XAC DINH QUAN HE G i f A DO LOfN L i f e KICH DONG VA QUI DAO CHUYEN DQNG HAT VAT LIEU TREN HOP SANG Voi may sang mng cd hudng ky hifiu mat sang NLS-5162/3: m-280 kg; C=370370 N/m; b^l85.2 Ns/ra Bang tinh toan ly thuyfit, nfiu giir nguyen cac gia tri b, C, m va thay ddi dp ldn lyc kich ddng (bang viec thay ddi m^^) theo tmong hgp gia dinh va giai he phuong trinh (3) de nhan dugc gia tri van tdc dao dgng Clia hop sang Theo lap Iuan d trfin, gia tri van tdc d a o * ^ ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, So nam 2017 NGHIEN CLfU-TRAODOI dpng cua hop sang ciing chinh la gia tri tuong ung voi van t6c ban dSu ciia hat vat lieu, cu th6 Ii; 0.8m/s; Im/s; 1.38m/s; 1.7m/s; 2.0m/s Khi do, Icet qua qui dao chuydn dong ung voi cdc van t6c duoc the hien tren hinh ""y^ ^ - T/ungVoS •"" hW ^~^^"^- \ '-y
Ngày đăng: 29/11/2022, 17:38
Xem thêm:
