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NGHIEN cdu-TRAO D C I NGHIEN CUtJ THlTC NGHIEIM BOI TRON CHAN THUY D Q N G EXPERIMENTAL RESEARCH ON HYDRODYNAIVIIC LUBRICATION FOR THRUST BEARING Nguyin v a n Long, TS TrSn Thi Thanh Hai Bp mdn May & Ma sat hgc, Vien Co khi, Trudng Dai hpc Bach Khoa Ha Npi TOM TAT Boi tran thuy dpng la phuang phdp duac sir dung bien cdc thiet bi vd mdy moc cong nghiep Be ndng cao tudi thp vd dp tin cay cda thiet bi thi viec nghien cuu boi tran thuy dpng la rdt cdn thiet Thong qua nghien ciru boi tran thuy dpng chiing ta co the tinh todn dup'c cdc dgc tinh ca bdn cua 6, dua hieu dp suat vd bieu nhiet dp tai vung chiu tdi cua 6, cho phep ddnh gid khd ndng tdi vd cdc dgc tinh cda 6, dua cdc bien phdp de gidm ma sdt vd mdi mon Do viec nghien ciru, xdy dung thiet bi khdo sdt dgc tinh cua chgn thuy dpng coy nghia quan trpng viec tinh todn kiem nghiem boi Iran cUng nhu tinh todn thiet ke Bdi viet ndy, giai thieu mpt nghien curu thuc nghiem ve cdc dgc tinh boi tran cua chgn thuy dpng Cdc kit qud se duac trinh hay bao gom dp sudt mdng ddu, nhiet dp mang ddu theo tdi tdc dting vd van tdc ciing cdch thirc hien thi kit qud lin mdy tinh thong qua truyen thong noi tiep Tir kho^: Boi tran thuy dpng, chgn thuy dpng ABSTRACT Hydrodynamic lubrication is the method commonly used in industrial appliances and machinery The study of hydrodynamic lubrication is necessary to improve the reliability and lifespan of the equipment Through the study of hydrodynamic lubrication we calculate the basic characteristics of the drive, the graph of the pressure and the temperature at the drive load, allows assessing the load and the characteristics of the drive, suppost the solution of reducing friction and wear Therefore, the research and design of hydrodynamic bearing characteristic investigated equipments play the important role in the test of lubrication process and the design of the drive The paper presents the practical experiment about lubricated properties of the hydraulic drive block The results are shown including pressure and temperature of the oil film when we change the load and the speed, and how to show the results to the computer via serial communication Keywords: Hydrodynamic lubrication, thrust bearing ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd +2 nam 2015 www.cokhivietnam.vn NGHIEN cufu-TRAO D | GIOI THIEU Bdi tran thuy dpng da va dang dugc nghien cuu rdng rai tren thd gidi Mdt nhiing cdng trinh nghien cuu ndi bat phai kk den dd la cudn sach cua J.Frene va cac cong su [1] duge xudt ban nam 1997 Trong cong trinh nghien cuu nhdm tac gia da dua ly thuyet tinh toan bdi tron cho d chan thuy dpng Nam 2000, eae tac gia A.L Brown, J.B MedHinh Cdu tao thiet bi vd dnh chup thiet bi ley, J.H Ferguson [2] da neu len han chg ciia 1) Khung may: 2) Tdm phdng cua chgn: bdi tran thuy ddng d chan diing cac 3) Tdm nghieng cita chdn: 4) Hop ddu: nha may thuy dien GSn day nhit, nam 2014, 5) Cum true chinh: 6) Ca cdu gia tdi: hai tac gia Zeng-rong Hao, Chun-wei Gu [3] da 7) Bp truyen dai: 8) Dpng ca: nghien curu va md phdng sd dugc qua trinh tao 9) Bp dieu khien: 10) May tinh hien thi: 11) Bien tdn bgt cua mang dau va nhirng anh hudng cua sy mat can bang cac d chan Nguyen ly lam viec ciia thiet bi: Nguyen ly hoat ddng cua thiet bi: Cum true chinh (5) nhan chuyen ddng quay tir dpng ca (8) qua bp truyen ddng dai (7) va lam quay tam phang ciia d chan (2) Khi tam phang quay so vdi tam nghieng (1) se tao cac chem dau tuong ung vdi mdi mudng ciia tam nghieng, cac chem dau ngan each hai be mat tam phang va tam nghieng De thay dupe mdi lien he giiia ap suat chem dau vdi tai trgng dat len cum true ehinh (5) ta tien hanh thay ddi tai trpng dat len true bang co cau gia tai (6) Hop dieu khidn (9) dugc gan len khung may (1) va dugc kit ndi dl Trong bai bao chung tdi nghien cuu hien thi len man hinh may tinh (10) Bidn tin (11) dimg de dieu chinh tdc ciia dpng ca thyc nghiem bdi tron cho d chan thuy ddng Tai Viet Nam, cac nghien cuu ve bdi tron thuy dpng ciJng da duge de cap dSn Giao trinh cdng ngh^ bdi tran ciia tac gia Nguyen Xuan Toan [5] da dua cae ly thuyet ca ban ve bdi tran G3n day, nghien cuu cua nhdm tac gia Luu Trgng Thuan, Nguyen Dinh Tan, Trin Thi Thanh Hai [6] da xay dyng chuang trinh ty dpng tinh toan bdi tron d dd cd tinh den hien tugng gian doan mang dau Cac nghien cuu ve bdi tran d chan thiiy ddng tai Viet Nam vln edn rat it - O chan: O chan dugc thiet ke nhu hinh THIET BI NGHIEN CtJtl THlTC 2, bao gdm tam phang (2) va tam nghieng (3) NGHIEM dugc thiet ke theo tieu chi dam bao tinh nang Thiet bi thyc nghiem dupe md ta nhu kl thuat, mang day dii mgi dae diem cua d hinh 1, thiet bi nham khao sat dae tinh eua d chan thiiy ddng ddng thdi ed the tdi uu ve chi phi che tao Ban kinh va ngoai ciia d la chan cd ket cau nhu hinh R,^20mm,R2^50mm, sd mudng Z^6, Muong cd dp nghieng 0,14°, chiSu day mang Idn nhdt va nhd nhat lan lugt la h,, h, '^ ISSN 0866 - 7056 TAP CHi CO KHI VIET NAM, Sd 1+2 nam 2015 www.cokhivietnam.vn NGHIEN cufu - TRAO Ddi t Hinh Ket cdu chgn Hinh Vf tri nhiet dp vd dp sudt - Vi tri do: Cac vi tri ap suat P1, P2, P3 dugc dat tren cung mdt muong nhu hinh va theo thir ty giam dan khe bd nham khao sat sy chenh lech ap suat chieu day mang diu giam dan Tam phang phia tren quay theo chieu kim ddng hd Cac vj tri nhiet dp T l , T2, T3 dugc dat tren mudng khac nham khao sat SU thay doi nhiet dp tren eae mudng - Cam bien do: Nhiet cua mang d&u dugc bdi cam biSn nhiet DS 18B20 (thdng sd chinh: Pham vi do: -55°C - +155°C; sai sd : ± 0,1°C; Thdi gian phan hdi 93,75-750^s) Ap suat cua mang dau dugc bai cam bien ap suit MPXHZ6400A (Thdng sd: Pham vi do: 20-400 kpa; Sai sd tdi da bing 1,5% gia tri do, thai gian phan hdi: 1ms) Khi sir dung cam biSn dien tii, tin hieu dua dugc bp vi xir ly tilp nhan va cac sai lech dupe tinh toan bii tru chuang trinh dieu khiln Do dd, he thdng hoat dpng dn dinh va cho ket qua dang tin cay - Phuang phap thuc hien va xir ly so lieu: Tiln hanh 10 lin va thdi gian each xa sau dd cac ket qua dupe cdng lai rdi chia trung binh Tien hanh dilu kien nhiet dp moi trudng la 19°C va ap suit du d bang khdng K E T QUA Ket qua dupe hien thi len phan mem dugc thiet ke bang phan mem visual studio thdng qua truyen thdng noi tiep qua cdng RS232 - Cac ket qua ap suat tren mdt mudng (1 chem dau): Hinh dua ap suat ciia d theo tai frgng 4kg, 8kg, 12kg tde 400 vg/ph Khi tai bing 4kg, cac gia tri ap suit t^i vi tri lin lugt la P l - KPa, P2=14 KPa, P - 23.5 KPa Khi tai bing 8kg, P l - KPa, P2=22 KPa, P 32 KPa Khi tai bing 12kg, Pl=10 KPa, P2-23 KPa, P3= 38 KPa.Ta thiy ap suit tai cae vi tri P1,P2, P3 theo thii ty tang din va dat gia tri Idn nhat tai vi tri (tuang umg vdi chilu day mang dau nhd nhit) Khi tai trpng tang thi chilu day mang dau giam dan va ap suit tang Dilu hoan toan phii hgp vdi ly thuylt Hinh bilu diln sy thay ddi ap suit cua mang dau theo van tdc tai tac dung la 8kg Khi n=300vg/ph, cac gia tri ap suit tai vi bi lin lugt la P l - KPa, P2=15 KPa, P 27.5 KPa Khi n = 0 v g / p h , P l = KPa, ISSN 0866 - 7056 TAP CHi CO KHI V I £ T NAM, Sd 1+2 nam www.cokhivietnam.vn 2015 NGHIEN cufu - TRAO O0\ P2=22 KPa, P3= 32 KPa, Khi n=500vg/ph, P l = KPa, P2=17.5 KPa, P3= 32 KPa Khi tdc tang tir 300vg/ph den 400vg/ph thi cac gia trj ap suit tang din Khi t6c dp tang tit 400vg/ ph den 500 vg/ph thi cac gia tri ap suit giam Nhu v^y, ban d i u t6c dp tang thi ap suit tang, toe dp tang den mgt nguong nao thi ap suat miing diu giam n=400v/p n=400 vg/ph Hinh Bieu nhiet dp thay doi tdi trpng I'- Hinh Ap sudt mdng ddu thay doi theo P-8kg Hinh Bieu nhiet thay doi tdc dg Nhiet dp tai cac mucmg la T l , T2, T3 xap xi bang d cac che dp tai trpng khac va van tdc khac Khi tang tai trpng hoac tang tdc dp quay thi cac gia tri nhiet dp tang len kha ddng deu, dieu phii hgp vdi ly thuyet diu d lien tuc trao ddi nhiet khdng ngiing :t_ Hinh Ap sudt thay doi theo tdc dp tdi trpng a toe dp 400 vg/ph tdi tdc dung Id 8kg - Cac k i t qua nhiet dp tren cac mudng khac nhau: Hmh va hinh bieu dien su thay ddi nhi?t dp ciia mang diu tai mudng theo tai tac dung va theo ^ c dp: K E T LUAN Bai viet da gidi thieu mgt n ^ e n ciiu thyc nghiem ve cac dac tinh boi tran d c b | n thuy ddng Tren mdt mudng ciia a chan, ap suat se tang din chieu day mang diu giam din Khi tai trpng tang, ap suat mang diu tang Ban diu tdc dp tang thi ap suit tang, tdc dp tang den mpt nguong nao thi ap suat mang d i u giam Nhiet dp tai cac mudmg'^ ISSN 0866'7056 TAP C H l C O KHi V I | T NAM, Sd 1+2 nam 2015 www.cokhivietnam.vn NGHIEN cufu - TRAO D O I xap xi bang d cac che tai trpng khac va van tdc khac Khi tang tai trgng hoac tang tdc dp quay thi cac gia tri nhiet dp tang len kha ddng deu.