DANH GIA TRANG THAI UNG SUAT BANH CAN REN VIT LAP DlTONG RAY TAU HOA V6l TA VET BE TONG BANG PHU ONG PHAP PHAN TU HlTU HAN Trdn Ve Qudc - Trudng Cao ddng Thiet bi Y te Nguyen Hun Phdn Trudng Cao ddng Kinh ti Ky thudt, Thai Nguyen Tdm tdt: Sir dung phuong phdp phdn tir hCru hgn plum tich trgng thdi ung sudt cho phep xdc dinh chinh xdc cdc dieu kien bien cua bed todn vd dnh huong ciia kit cdu din bin cdc chi tiet mdy Bdi bdo trinh bdy img dung thudt todn ciia phuong phdp phdn tir huu hgn tich hgp phdn mim ANSYS dexdc dinh tnrdng img sudt ciia bdnh cdn ren vit cudng cao Kit qua ciia bdi hdo dua tnrdng phan bo img sudt ciia bcinh cdn ren vit cudng dg cao Ket qud ndy cd thi dugc sir dung tinh todn, kiem tra cho cdc true cdn hinh cd dieu kien lam viec tuong tu Abstact: Use finite element method to analize stress stutus enable us to detennine correctly the boundary conditions of the problems as well as to determine the affects of structs to the strength of machine components This paper shows the application of the finite element method algorithm built-in in the ANSYS software to determine the stress field of high intensity screw roller The results shown here are the stress distribution field of high intensity screw roller Tliis results can be use in calculating, testing for the shaped rollers with the same working conditions I Dat van de Do ben dnh hudng rdt Idn den khd ndng lam vide cua banh cdn ren tir dnh hudng nang suat, chdt lugng va hieu qud kinh te cua qud trinh sdn xudt ren vft Cdc dang hdng xudt hien tren bdnh cdn: trdc, ro, mon, dfnh bd mat ren; nut tai chan ren; bi bien dang du, gay gidn lap be mat; phd hdng tmh d chan ren hodc bi nut tai tidt dien cd ranh then Nguyen nhdn chfnh cua cdc dang hdng ndy la viec tfnh todn ben cua bdnh cdn chua thye sy chfnh xdc Vi vay, vide lya chgn phuang phdp kiem tra ben bdnh cdn hgp.ly vd cho ket qua ddm bdo chfnh xdc la rdt quan trgng Khd khdn Idn nhdt cua bdi todn tfnh ben cho bdnh can viec dua vdo day du cac thdng sd dieu kien bien Vi vdy, su dyng phuang phdp phdn tii hiru ban se cho phep xdc dinh day du va chfnh xac cdc thdng sd tren Trong bdi bdo tdc gid trinh bdy viec su dung thudt todn cua phuang phdp phan tii hiru han tfch hgp phdn mem ANSYS de gidi bai todn ben cho bdnh edn qua dd xac dinh chfnh xac dnh hudng cua cdc yeu td (lyc cdn, nhiet cdn, ca tfnh cua vat lieu va ket cdu ciia bdnh cdn) den ben ciia nd n Xac dinh dieu ki£n bien ciia bai toan • • Do chfnh xdc ket qud ciia bdi todn cd quan he mat thiet vdi viec nhap cdc didu kidn bien tien hdnh tfnh Vi vdy cdc dieu kien bien dugc dua vdo qud trinh tfnh phdi ddy du vd chfnh xac 2.1 Xac dinh lyc tac ddng len banh can 187 Tfnh toan lyc can Ren vfl dugc ch^ lao bdng phu'O'ng phap can ndng vdi 02 banh can, vi vdy luc can dugc xac dinh nhu sau: Luc hudng kinh tdc dung len bdnh cdn dirge tinh bdi cong thiic: P.= (1) dl + D^ Trong dd: Pp - luc can hudng kfnh, (kG) V|/w- he so thue nghiem, \|/w= 1,1 - 1,9 \|;b-h?sd tidp xiic, 1Kb =0,95 f he so ma sat, f = 0,065 ^0,095 Ob = 40 img sudt ben cua phdi cdn hinh 4.3 [1], kG/mm di = 16 - dudng kfnh chan ren vft cdn, mm Dp = 24 - dudng kfnh dinh ren vft cdn, mm A = a.S; B = b.S, mm vdi a, b la he so; S - la budc ren, mm, a = 1,69 + 2,41; b = 4,55 + 6,86 A = 2,0 12,5 = 25mm ; B = b.S = 5.12,5 = 62,5mm Dodo: ^ l,15.1,5.400.0,095.0,8.16.24.(25 + 62,5) ^ ^^^^ ^^^^^ 16 + 24 " ->Pp= 44050,6 N Lice can tiep tuyen tdc dung len bdnh cdn: Pt = 0,08.Pp (2) ^ Pt = 0,08 44050,6 = 3524 N Sa phan bo lyc tren banh can Gid thiet lyc can hudng kfnh vd tidp tuyen dugc chia deu cho dinh ren tren banh can nen gid tri ciia cdc lyc tai cac vi tri nhu sau: Ppi = Pp/8 (i = 1^8) (3) ->Ppi = 44050,6/8 = 5506N P,i = P./8 (i = lH-8) (4) -> Pti =3524/8 = 44 IN Tacd so dd sau: ''-ip''p'iJ'^ip''p'ip''-ip''.-f P - P' Hinh I So dd chiu lyc cua banh can 188 2.2 Nhiet can ren vft Nhiel Idn nhdt nung phdi can ren vft duoc ihuc hien 800"C va qua Innh nung duoc thii'c hien theo hai giai doan: Giai doan thir nhdt: nung so bd phdi den 250"C Giai doan thir hai: nung phdi den nhiet can 800°C Vi vdy, tfnh ben cho bdnh can can tfnh tai thdi diem nhiet cao can cao nhdt (T°cdn = 800"C) Ngodi hai dieu kien bien co bdn tren, qua trinh tfnh cdn chii y den dnh hudng ciia v^t lieu (E = 2,1.10"'' Mpa, £ = 0,3), dnh hudng cua ket cau qua vide chgn sa dd d^t luc tai vi tn tiet dien ranh then (hinh 2) Hinh So dat luc III Tinh toan ung suat, bien dang Phdn tir hiru ban la phuang phdp dugc sir dung rgng rai viec tfnh bdn cho cdc chi tidt mdy, nhdt la cdc chi tidt cd dang kfn va cho chfnh xdc cao Tuy nhien sd lugng phep tfnh cua phuang phdp Id rdt Idn Phdn mem Ansys la phdn mem rdt manh viec iing dung thudt todn ciia phuang phdp phdn tu hiru ban gidi cdc bdi todn ky thudt (phdn tfch ket cdu, ddng lyc bgc bien dang, \ \ t phan tfch nhiet ) Nhung Ansys lai la phdn mem rdt kho khdn vide xdy dyng hinh dang, hinh bgc ba chieu ciia cdc kdt cau nhdt Id cdc kdt cdu phu:c tap Bdnh cdn ren vft Idp dudng ray tdu vdi ta vet be tdng co hinh dang rdt phiic tap Vi vdy, tfnh ben cho bdnh cdn tdc gid dd xay dyng md hinh 3D cua chi tidt tren phdn mem Pro/engineer Id phan mem rdt manh thiet kd, sau xdy dyng mdi quan he giua Pro/engineer vd Ansys de tien hdnh tfnh todn mdi trudng Ansys Nhu vdy se cho chfnh xac rat cao cd xay dyng md hinh vd tinh todn 189 ("BEGIN) Mo hinh 3D Pro/engineer ANSYS Chon phdn tCr Nhdp vdt IISu I I Chia phdn td Dieu ki§n biSn I Tfnh todn K§'t qua (T,o,E) vd mo phdng I MEND) Hinh So khdi phan tfch iirng sudt vd bien dang ciia bdnh cdn Md hinh 3D cua bdnh can tren phdn mem Pro/engineer, hinh Nhap md hinh bdnh can vdo mdi trudng Ansys, hinh Thye hidn cdc budc tfnh toan tren moi trudng lam vide ciia Ansys: kidu phdn tir 10 node SOLID92, E = 2.1.10^Mpa e = 0.3; rcan = 800°C Phdn mdm se cho kdt qua theo muc dfch ciia bdi toan 190 IV Kdt qua 4.1 Ket qua bien dang ciia banh can 3!|j|,5XJ';r']!'"*!'"'"!'^''!r,'^;i"'ri5;ii 1||!I>1 '5,.;:' 83^^'' •i':7/' '*., : ; ",'• A ', ('"111:' ,.iM a'.(ii '••:M ^