Do Dijc Trung vd Dtg Tap chi KHOA HQC & CONG NGH$ 128(14): 17-22
NGHIEN CUtJ ANH HlTOfNG CUA LlTONG CHAY DAO
DEN C H A T L i r O N G BE MAT GIA CONG T H E P 20X T H A M CAC BON KHI MAI V 6 J A M CHAY DAO HlTOfNG KINH
D6 f)uc Trung'*. Ng6 Cu6ng', Phan Bui KhoiS Phan Thanh Chuong', Nguyln Thanh Chung^
'Trudng CD Kinh le Ky ihuai - DH Thai Nguyen. 'Trudng Dgi hoc Bach Khoa Hd Noi 'Trudng Cao ddng nghe Cong nghep \'iet hoc Vmacomin
TOM TAT
Bai bdo nay trinh bay nghiln cu-u anh huong ciia lugng chay dao d6n chat lucmg bl mat gia cong tinh thep 20X tham c^c bon khi mai v6 tarn chay dao huong kinh. Hai thfing so dac trung ciia chat lugng be mat gia cong dugc khao sat trong nghien ciru nay gom dp nham (Ra) va dp khong tr6n (A). Tir do dua ra dugc mire do anh hudng ciia luang chay dao den do nham va do khong tron.
Dong then, nghien ciru nay cung chi ra khoang chay dao hop ly khi gia cong tinh mac th^p 20X tham cdc bon bang phuorng phap mai v6 tam chay dao huong kinh.
TCr kh6a: Mdi vd tam chay dao hudng kinh. do nham, dp khdng tron. thep 20X, luang chay dao huang kinh
GIOI THIEU
Trong gia cdng ca khi, mai v6 tam la mgt phuang phap gia cdng cd nang suat cao han nhieu Ian so vdi mai cd tam nhd che dp gia cdng cao, thdi gian ga dat, hieu chinh va thao dd chi tiet it [1, 2], Ngoai ra, do khdng can djnh tam chi tiet nen cd the giam bdt lugng du gia cdng vi chi tiet dugc dinh vi chinh bang be mat gia cdng; cd the nang cao che do mai vi chi tiet dugc ga tren thanh ty va da dan nen cd do eirng v&ng cao; neu su dung da cd chieu day Idn cd th6 giam dang kk sd Ian chay dao dgc; cd the gia eong cac chi tiet dai hoac nhieu chi tiet ddng thdi bang phuong phap chay dao hudng kinh [3].
Trong phuang phap mai vd tam, chat krgng vat mai dugc danh gia qua nhieu thdng sd.
Trong do, do nham va dp khdng trdn la nhirng thdng sd quan trpng quyet djnh chat lugng vat mai [1, 2, 3]. Chat lugng b€ mat khi mai phu thugc nhieu vao cac dac tinh ciia chi tiet gia cdng [3]. Theo [4,5] dp ciing va dp ben keo cua vat lieu gia cdng co anh hudng manh den luc cat, nang lugng cat, qua dd anh hudng den tai trgng co nhiet ciia qua trinh cat. Ngoai ra, toe dp mon hat mai phu thupc vao dp cirng
Tel: 0988 488691, Email: dotrung. th@gmail cam
ciia vat lieu gia cdng [5] lam thay ddi mire do cao xude ciia hat mai Ien be mat gia cdng.
Day la nhiJng nguyen nhan c6 anh hudng dang ke den chat lugng be mat mai.
Doi vdi thep 20X tham cac bon sau khi nhiet luyen thuong dat dp ciing 60-62HRC, dp ben keo ciia mac thep nay cd gia trj trung binh so vdi nhdm cac mac thep hgp kim thap thdng dung, ob ~ 430-470 N/mm' [6]. Day la mgt trong cac mac thep dien hinh dai dien cho nhdm thep hgp kim thap dugc su dung rpng rai trong nganh che tao may. Mac thep nay hien dang dugc Cdng ty TNHH Nha nude mot thanh vien Diesel Sdng Cdng Thai Nguyen va mgt sd cdng ty khac dung de che tao chi tiet con dgi xupap ciia ddng co diesel, chdt piston, guddng,dd'dinh'vj ciia do ga. . vdi phuang phap mai vd tam dUgc chon de gia cong cac be mat try yeu cau do chinh xae cao.
Da cd mgt sd nghien ciiu ve dp nham va do khdng trdn ciia chi tiet khi mai v6 tam chay dao hudng kinh dugc cdng bd: danh gia dp nham be mat bang hai phuang phap sua da khi sir dung but kim cuong va dTa kim cuang [2]; anh huang ciia mgt sd thdng sd ddng hinh hoc den dp nham be mat [7, 8, 9]; anh hudiig cua van tdc cat d€n dp nham hk mat gia cong [10]; mdi quan he giira dp khdng trdn cua chi
17
Bo Due Trung vd Dtg Tap chi KHOA HOC & CONG N G H S 128(14): I?
tiet va gdc nghieng thanh ty y, goc tiep tuyen P (hinh 1) [2]; phan tich nhung han chi cua phuang phap siia da thdng thudng anh hudng den dp tron ciia chi tiet [II, 12]; anh hudng ciia dp chinh xac cua da dan den dp khdng trdn ciia chi tiet [13]; phan tich v6 rung ddng va qua trinh tao dp trdn cua chi tiet [14]; khao sat dp khdng trdn ciia chi tiet trong ca hai trudng hgp mai vd tam: chi tiet cao hon tam da va chi tiet thap han tam da [15, 16]; Anh hudng cua tdc dg da dan den do khdng trdn ciia chi tiet [10]; mdi quan he giua do khong trdn vdi gdc tiep tuyen va lugng chay dao khi sii'a da, mdi quan he giira do khdng trdn vdi gdc tiep tuyen va van tdc chi tiet [17]; mgt sd ggi y de dam bao do trdn cua chi tiet gia cdng [18]; anh hudng ciia ty le van tdc da mai/van tdc chi tiet den do khdng trdn [19]; nghien cii'u mo phdng anh hudng ddng thai cua mot sd thdng sd dgng hinh hpc eiia qua trinh mai den dp khdng trdn [20]... Trong nghien cii'u nay chung tdi tien hanh khao sat anh hudng CLia lugng chay dao (SK) den dong thdi hai thong sd do nham va do khdng trdn khi gia cdng tinh thep 20X tham cac bon bang phuang phap mai v6 tam chay dao hudng kinh. Tir do dua ra duge muc do anh hudng cua lugng chay dao den dp nham va do khdng trdn. Ddng thdi, nghien cuu nay cung chi ra khoang ciiay dao tuang ddi hgp ly khi gia cdng tinh mac thep 20X tham cac bon bang phuong phap mai v6 tam chay dao hudng kinh.
SO DO GIA CONG
So dd gia cdng khi mai vd tam chay dao hudng kinh dugc the hien tren hinh 1. C) phuong phap nay, chi tiet dugc dat giira da mai - da dan va thanh ty. Trong qua trinh gia cdng, da dan - chi tiet va thanh ty se tien dan ve phia da mai.
Bang I. Thanh phan hda hoc chinh ciia
Hinh I. Sa do mdi vd tam chay dao hudng kinh HE THONG THI NGHIEM
Mau thi nghiem
Mau thi nghiem la mau thep 20X tham cae bon (hinh 2), co thanh phin hoa hoc trudc va sau khi tham eac bon dugc trinh bay trong bang
!
in
CM
13
^
25 o
1
S
80
CM C3
- 4
25 Hinh 2. Man thi nghiem May thi nghiem
Thi nghiem dugc ti6n hanh tren may mai v6 tam M1080B do Trung Qudc san xuat nam 2011 tai Xuong ea khi 11 - Cong ty Cd phkn Co khi Phd Yen - Thai nguyen (hinh 3) vdi cac dac tinh ky thuat nhu sau:
-Damai:Cn80.TB,.G.V|.500.l50.305x35m/s - D a d i n : R.273.150.127
- Thanh ty: 7 = 30"
thep 20X trudc vd sau khi tham cac bon
20X Truoc khi tham C
Sau khi tham C C 0,209
1,02 Si 0,208 0,212
Mn 0,74 0,51
P 0,015 0,018
S 0,015 0,017
C r 1,16 0,78
Ni 0,013 0,017
C u 0,018 0,021
Q6 Dire Trung vd Dtg Tap chi KHOA HOC & CONG NGHE 128(14)' 17-22
Hinh 3. May thi nghiem Thiet bj do
- Dg nham be m^t gia cdng dugc do bang may SJ400 ciia hang Mitutoyo - Nhat Ban (hinh 4).
1
31.1' r
Hinh 4. Mdy do dp nhdm SJ400 - Do khdng trdn ciia chi tiet dugc kiem tra bing dong ho do 5/10000 (hang HJ - Dai Loan), viec dieu chinh vj tri khdi V dd chi tiet dugc tien hanh bang ddng hd do 1/1000 (hang Mitutoyo - Nhat Ban) tren may do do thang MMM-23(hinh5).
Hinh 5, Thiet bi do dp khong trdn
Dieu kien thi nghiem
-Van toe da mai: 34 m/s (n^ = 1300 v/ph) - Van toe da din: 30,85 m/p (nj = 36 v/ph) - Chieu cao tam chi \\k h = 12 mm (P = 7,14°).
- Dung djch tron ngudi: UNIMET AS 192 (hang Oemeta Dire), ndng do 4% vdi phuang phap tudi tran.
- Lugng du gia cdng tinh theo ban kinh: 0,05 mm - Da dan dugc xoay trong mat phang thang dirng mgt gdc 0,5**, xoay trong mat phSng nam ngang 0°.
- Sua da dan:
+ Chieu sau sua da: 0,01 mm + Lugng chay dao dgc: 30 mm/ph + Van tdc da din: 257,3 m/ph (nj = 300 v/ph) - Sua da mai:
+ Chieu sau sira da: 0,01 mm + Van tdc da mai: 34 m/s (nd= 1300 v/ph) + Lugng chay dao dgc: Sd = 300 mm/ph - Lugng chay dao hudng kinh: SK = I -^ 21 ^im/s KET QUA VA THAO LUAN
Tien hanh mai thi nghiem vdi cac gia trj khac nhau eiia lugng chay dao hudng kinh (SK).
Tai mdi diem thi nghiem tien hanh vdi 3 mau.
Tien hanh do dp nham hk mat tren chieu dai chuan L = 0,08 mm, gia tri dp nham tai mdi diem thi nghiem la gia trj trung binh ciia cac lan do. Dp khdng trdn duge do tren cac mau la thdng nhat tai mot tiet dien nhd cd cir chan chieu true duge gan tren khoi V, gia tri dp khong trdn tai mdi diem thi nghiem duge xac djnh bang sd vach chi thj tren ddng hd 5/10000 sau dd lay gia trj trung binh cua cac lan do. Ket qua ve dp nham va dp khdng trdn dugc the hien tren bang 2 va dd thi hinh 6, hinh 7.
Tir ket qua tren bang 2 va hinh 6, hinh 7 ta cd nhan xet:
- Lugng chay dao cd anh hudng dang ke den ca dp nham va do khdng trdn ciia be mat gia cdng.
Do Dire Trung 7 Dtg Tap chi KHOA HOC & CONG NGHE 128(14):
- Muc dp anh hudng cua lugng chay dao den - Khi mai tinh thep 20X thim cac bon la tr;
dp khong trdn nhieu hon anh hudng den dp dp nham va dp khdng trdn dlu cd gia tri nhd nham hk mat. va tuong ddi dn djnh khi SK = 2 - 3 ^ini -
Bang 2. Gid tri dp nham vd dp khdng trdn khi thay doi St:
Do nham I trdn
PT
1 2 3 4 5 6 7 8 9 10 11
SK (em's)
1 3 5 7 9 11 13 15 17 19 21
Ra, (Mm) 0,71 0,53 0,45 0,47 0,60 0,45 0,61 0,56 0,64 0,59 0,70
Ra,
(("")
0,69 0,43 0,50 0,43 0,56 0,50 0,60 0,50 0,63 0,58 0,70
Ra, (I'm) 0,71 0,55 0,45 0,41 0,53 0,45 0,55 0,52 0,51 0,65 0,76
Ra (Mm) 0,70 0,51 0,46 0,44 , 0,56
0,46 0,59 0,53 0,59 0,61 0,72
A,
(Mm) 11,0 2 2,5 1,5 1,0 1,0 3,0 2,0 1.5 2,0 3,5
A , (|im)
11,0 1,5 1,5 2,0 1,5 1,0 1,5 2,0 2,0 2,0 3,5
A , (Mm)
13,0 2,0 2,5 2,0 2,0 1,5 2,0 2,0 1,5 2,5 4,0
A
(|im) 11,67 1,83 2,17 1,83 1,50 1,17 2,17 2,00 1,67 2,17 3,67
L i i o n s cba-^- dao hw I kinh S (tnicromet's) Hinh 6. Anh hudng cua It ^ chay dao den dd nhdm be mat
if i « : - -
\ . ' ^ . X . ^
6 11 16 21 L u - g n g c b a y d a o hirffng k i o b S ( n ] i c r o m e t ' s )
Hinh 7. Anh hudng cua luang chqy dao den do khdng trdn
D6 Dire Trung vd Dig Tap chi KHOA HOC & CONG NGHE 128(14): 1 7 - 2 2
K E T L U A N
- M u c dp anh h u d n g c u a l u g n g chay dao den dp khdng trdn nhieu h a n anh h u d n g den dp nham be mat
- Khi mai tinh thep 20X t h l m cac bon nen chgn l u g n g c h a y d a o h u d n g kinh trong khoang SK = 2 -^ 18 jim/s. Ket qua nay cung cd the d u g c diing d e tham khao khi gia c d n g tinh cac m a c vat lieu thugc nhdm thep h g p kim thap.
- Tren c a sd khoang t u o n g ddi hgp ly eua lugng chay dao ma nghien cuu nay da chi ra, chiing tdi se tien hanh nghien cuu tdi uu gia trj ciia thdng so nay trong lighien cim tiep theo.
TAI LIEU T H A M K H A O 1. Nguyln v a n Tinh , Ky thuat mdi, Nxb Cong nhan ky thuat, HA N6i (1978).
2. Loan D. Marinescu, Mike Hitchiner, Eckart Uhlmann and W. Brian Rowe, Handbook of machining with grinding wheels, CRC Press Taylor & Francis Grojp (2006).
3. Luu van Nhang, Ky thuat Mdi kim logi, Nha xuat ban KH&KT, Ha Noi (2003)
4. Loan D. marinescu. W. Brian Rowe, Boris Dimitrov and Ichiro Inansaki, Tribology of abrasive machining process. Published in the United States of America by William Andrew, Inc (2004).
5. Milton Shaw, The size effect in metal cutting, Sadhana Vol. 28, part 5, October 2003, pp 875- 896, Printed in India.
6 Mechanical properties of alloy steel (Chinese standard: GB/T 17107- 1997)
7. J. Kopac, P. Krajnik and J.M. d'Aniceto, Grinding analysis based on the matrix experiment, 13"" International scientific conference on achievements in mechanical and materials engineering (2005).
8. P. Krajnik, A. Sluga. J. Kopac, Radial basis function simulation and metamodelllng of surface roughness in cenlreless grinding. Faculty of IVIechanical Engineering, University of Ljubljana, Askerceva 6, SI-1000 Ljubljana. Slovenia (2005).
9. P. Krajnik, J. Kopac and A. Sluga, Design of grinding factors based on response surface
methodology. Journal of Materials Processing Technology 162-163 (2005).
10. S.S.Pande and B.R Lanka, Investigation on the through - feef centerless grinding process, International Journal of Production Research Volume 27. Issue 7 (1989).
11. F Hashimoto, A. Kanai. M. Miyashita, K.
Okamura. High Precision Trueing Method of Regulating Wheel and Effect on Grinding Accuracy, Annals of the C/RP Vol. (1983).
12. Albert J, Shih, A New Regulating Wheel Truing Method for Through-FeedCenterless Grinding, Contributed by the Manufacturing Engineering Division for publication in the journal of Anufacturing science and engineering (2000).
13. P. R. Nakkeeran and V. Radhakrishnan, A study on the effect of regulating wheel on the roundness of workplece In centerle.ss grinding by computer simulation. Int. J. Math. Tools Manufact Vol, 30, No. 2, pp. 191-201 (1990).
14. Yuji Furukawa, Masakazu Miyashita and Susumu Shiozakij, Vibration Analysis and Work- Rounding Mechanism in Centerless Grinding, Int.
J. Mach. Tool Des. Res Vol. 11,(1971).
15. N. G. Subramanya Udupa, M. S. Shubnmugam and V, Radhakristinan, Influence of wurkpiece position on roundness error and surface finish in centerless grinding. Int. 1. Mach. Tools Manufact.
Vol. 27. No. 1. p. 77-89(1987).
16. C. Guo, S.Malkin. J.A.Kovach and M.Laurich, Computer Simulation of Below-Center and Above- Center Centerless Grinding, Machining Science and Technology, 1(2), 253-249 (1997).
17. S.S. Pande, A.R. Naik and S.Somasundaram, Computer simulation of the plunge centreless grinding process. Journal of Materials Processing Technology, 39(1993).
18. F. Hashimoto. G. D. Lahoti, M. Miyashita, Safe Operations and Friction Characteristics of Regulation Wheel in Centerless Grinding, Tokyo, Japan Received on January 5 (1998).
19. W. B. Rowe, S. Spraggett, R. Gill and B. J Davies, Improvements In Centreless Grinding Machine Design, Annals of the CIRP Vol (1987).
20 Phan Bui Khoi, Ngo Cuong, Do Due Trung.
Nguyen Dinh Man, A study on simulation of plunge centerless grinding process, ISEPD 2014 - International Sysposium on Eco-malerials Processing and Design, Ha Noi. Viet Nam (Jannuary 12-14, 2014)
Do Due Trung vd Dtg Tap chi KHOA HOC & CONG NGHE 128( 14): I '
S U M M A R Y
I N F L U E N C E O F T H E P L U N G E F E E D - R A T E O N Q U A L I T Y O F W O R K P I E C E S U R F A C E W H E N G R I N D 2 0 X - C A R B O N I N F I L T R A T I O N S T E E L U S I N G P L U N G E C E N T E R L E S S G R I N D I N G P R O C E S S
Do Due Trung'", Ngo Cuong', Phan Bui K h o i \ Phan Thanh Cliuong', Nguyen Thanh Chung^
'College of Economics and Technology - TNU - Hanoi University of Science and Technology
^Vmacomin - Viet Bac Industrial Vocational College This paper presents the research on the influence of the plunge feed-rate on quality of workpiece surface when grind 20X - carbon infiltration steel using plunge centerless grinding process. Two parameter of quality of workpiece surface which consider in this paper are roughness (Ra) and error roundness (A) So, give the influence of the plunge feed-rate on roughness and error roundness. Also, this work carry the logical range of plunge feed-rate when grind grind 20X - carbon infiltration steel using plunge centerless grinding process.
Keywords: Plunge centerless grinding. Roughness. Error roundness. 20Xsteel. Plunge feed-rate
Ngdy nhan bai 24/9/2014. Ngdy phan bien. 03/10/2014; Ngdy duyet ddng. 25/11/2014 Phan hien khoa hoc: PGS. TS Nguyin Qudc Tudn - Dai hoc Thai Nguyen
Tel 0988 488691. Email dotrung lh(aigmail c.
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