V A N DE H O M N A Y
Xu hudng mem trong
C
iic kim loai mem (dp ctfng thap) cd kha nang bie'n dang tUdng dd'i Idn. Trong dd cd ddng. nhdm va mdt sd hdp kim khac nhu ddng thau, cd the xem la mem hdn so vdi cac kim loai khac nhU sat va thep. Vi vay se cd mpt vai can nhac can dUdc lUu y de'n khi gia cdng nhtfng kim loai mem nay.Do nhtfng kim loai nay cd dp ctfng, ran khdng cao nen cac dao ed khi de dang eat, vi the phe pham cat (mat giu) cd the dinh vao ta'm kim loai hoac ludi cat, lam cho ehi tiet khd dUde gia cdng, tiing dp mai mdn vii giam tudi thp cua dao. Dp phan xii td't eua ciic kim loai mem cung lam cho mdt so phu'dng phap gia cdng khdng tiep xuc, nhu lii laze khdng hieu qua. Vi vay, qua trinh gia cdng can diing cae dung cu, may mdc vii cdng nghe dac biet.
De giam sif tich luy mat giti, ngu'di ta diing cdc chat bdi trdn dac biet.
Trong dd, mpt trong nhtfng chiit bdi trdn phd bien lii Alumtap. Alumtap la mdt hdn hdp khdng dde hiii dUde dac che eho phu hdp vdi ciic tinh chat gia cdng eiia nhdm vii nhtfng kim loai mem khiie. Khi dUde stf dung trifc tiep, Alumtap se hiin che hiin diem vii giiim xu hifdng kim loiii mem dinh viio lUdi cua dung eu cat. Dieu niiy cai thien nang lull y, keo diii tudi thp eiia dung cu vii giup be miit cifc min vtfa sach vtfa sang.
Oxit ziriconi nitd
Mpt vi du khiic la Idp phii oxit ziriconi nitd (ZOX), khdng ed titan va dUde difa viio stf dung d dao phay trong loiit hang GARANT HPC mdi.
Ldp phii ZOX giiim thieu he sd ma sat d mat ciit vii diim bao sif phan tan hieu qua eiia eiie phdi gia cdng. Cac dao ket hdp ldp phii eiia GARANT cdn cd nhtfng ninh Idn dUde diinh bdng vii cac hoc rdng dUde thiet ke dae biet de tdi Uu hoii qua trinh quel bd mat giu.
Ciic dao ciit dUpe phu ZOX, eu the phu hdp vdi ciic phdi gia cdng nhdm
\ d n ddi hdi ehiil lUdng be mat cao. Do lifp phii khdng cd tilan dao cQng thoii miin dUde eiie yeu ciiu eua ngiinh cdng nghiep hiing khdng hi gia cdng hdp
kim nhdm khdng nhiem tap chii't. Cd 7 loai dao phay dau HPC ttf carbide nguyen khdi vdi ldp phii ZOX, bao gdm cae mui khoan ranh sieu nhd ttf carbide nguyen khdi hai riing, dao cat hinh xuyen sieu nhd 2 riing, mui khoan riinh hinh cau ban kinh day sieu nhd 2 riing, Ciic dao phay ngdn thd 3 va 4 ning khdng cd hinh khuyu, dao phay ngdn 6 vii 8 riing vii mdt loat cae mui khoan ranh cau sieu nhd 2 rang.
Cac thtf nghiem dUde tien hanh bang each gia cdng hdp kim nhdm .AlCuMg, vdi tdc dp eat la 1.130 met/
phut, vdi lUdng chay dao lii 0,224 mm vii dp sau eiia vet cat la 20 mm, bang dao phay ngdn thd ttf carbide nguyen khdi. Ket qua chtfng minh rang, dao phu ZOX giiim thdi gian gia cdng va chi phi siin xuat song song vdi cai thien chat lupng mat ciit.
Gia cong cd Idil
Nhieu loiii thiet bj khac nhau difdc stf dung trong gia cdng, ma d dd cae loai dao cat, dao phay va cac trung tam gia cdng la tru edt.
Mdt vi du eiia dao eat danh cho cac kim loai mem la dao phay ngdn hang hang loat 4081 ttf nha siin xua't dao cat chuyen nghiep ITC. Loat hang 4081 lil dao phay ngdn carbide nguyen khdi bdn ninh dUde phii AlTin vdi cii'u tnic hinh hpc ranh hiii hoa giup quel bd mat giu cUe td't. Loiit hang 4081, ehudi ddn. thiing. dau vudng vdi dUdng xoan
dc phai cd khoang each ranh hUdng tam khdng bang nhau tao dp vtfng chac va lu'dng quet bd kim loai cao khiic thudng, trong khi khoang each ranh eua loat hang 4081 giam rd net tie'ng dn gia cdng bang each giam hieu qua hoa am.
Cae dao dung cho kim loai mem khdng dUde sdn phu cung cd the d dang dao cat carbide nguyen khdi. Vi du, hang loat dao phay carbide nguyen khd'i 93033 ttf WNT vdi dUdng kinh ttf 3mm de'n 20 mm va cd dang hinh miii ddn khdng cd gdc sau. Hinh dang nay lam cho lUdi eat rat ben va sic, tao tdc dp cat vii lupng chay dao trong trong qua trinh gia cdng nhdm cao hdn rat nhieu so vdi cae dao cat thdng thUdng.
Thife ra, WNT (Anh) dang bao cao stf gia tang tdc dp tdi 25% va lUdng an dao tang vpt Ien 250% trong nhtfng lan cat thuc nghiem. Cau true hinh hpc vii gdc xoan dUde thiet ke dac biet tang dp phan tan mat giu va gdp phan vio nang cao hieu luXi y cdng cu. Nhtfng dao cat nay li tUdng cho gia cdng nhtfng ranh day, do ldi cua nd ctfc ki chac chan, vdi khii nang phay ranh toan phan tdi gap 1,5 Ian so vdi biin kinh gia cdng bdi quii trinh trUe tiep.
WNT cung ed nhieu loiii insert danh cho gia cdng nhdm, titan ya ciic hdp kim nhe khac, de eung cap cho ngUdi stf dung ldi ich gia/ciinh rd r?t.
TrUdc dd. nhtfng in.sert can cd ^^^
ciit sac phai dUdc mai de dat dtfdcC^
T A P C H i C d K H i V I E T N A M • So 1 o - Tlian.u H n;lm 2009
VAN DE H O M N A Y
C ^ d d chinh xac, phai thoa man nhtfng yeu cau vd kha nang lap lai cung nhU chiit lUdng be mat tren phiin dUde gia cdng.
Tiet l(igni clii plii
Hien nay, vdi sif tien bd ciia cdng nghe nen, Ciic insert cd the dat khoang 90% hieu sua't va nang suat cua insert tan siin vdi chi phi tiet kiem cd the tang len tdi 40%. Vi du, insert dien hinh DCXT 11T304 itf loiit hang mdi nay cd gia 2,84 biing Anh (1,42 bang/ludi), trong khi insert tan san tUdng dUdng DCGT 11T304 cd gia 4,11 bang (2,05 bang/lifdi).
He thdng dao thao lap stf dung cae insert la OvalFlex, dUde thie't ke bdi Ceratizit, diing cho gia cdng cac banh hdp kim nhdm. FTinh oval da dang ki bang sang che ciia he thdng lam cho chieu cao lap rap cua dao cao hdn cae dao binh thu'dng, cai thien dp ben cho toan bd he thdng dao. Giao dien hinh oval lien ke't ehudi dao vdi dau dao. Bdn be mat dang cdn xung quanh giao dien tao ket ndi chinh xac vdi mat dinh vi theo ca phUdng hifdng tam va true.
He thdng OvalFlex eung gia tang kha nang linh hoat de rap nhieu loai dau dao vao ehudi.
Trong hau he't cac tru'dng hdp, dao chuyen dung khdng cdn ciin thiet ntfa. Cac insert vdi nhieu ban kinh khac nhau cd the stf dung dUde trong cung mdt dao. Vi du, X32 mdt insert dac biet cua Ceratizit, Idn hdn cae insert khac va cifc ki ben vtfng. Nhd vao cac mat chdp ed gdc 300, vi tri ehinh xac khdng cdn la van de. Ben canh dd insert can bang life cat ngang tdt hdn. X32 dUde b i o ve ehdng lai cat keo nhd vao cac mat chdp dang hinh cdn. Insert cd ban kinh 4mm, 3mm hoac 2mm, diing carbide hoac PCD (kim cUdng da tinh the), trong dd ciic insert PCD ed ranh phdi laser de tdi Uu hoa viec kiem soat miit giu.
Nhu viiy, ed the ndi den nay, xu hUdng mem trong gia cdng kim loai dang cd nhtfng Uu the nhat djnh. Vi viiy, nd eung htfa hen mpt tUdng lai kha quan trong nganh cdng nghiep ndi chun^, cdn^ nghiep cd khi ndi rieng. •
DUY TUAN
Tai nan lao dong trong san xuat cof khi thu cong:
Nguy cd vin tiem an
Hi
a Ndi ed rat nhieu lang .nghe cd khi thu cdng, nhifng ddng thdi vdi sif phat trien cua cac lang nghe la stf gia tang tai nan lao dpng. Tai nan lao dpng^ ^ ^ ^ trong cac lang nghe L ' § i j ^ ^ ^ . ^ r ^ i ^ ^ l ^ ^ ^ W W san xuat cd khi tUdng I ^ ^ ^ M K ^ ^ ^ nhtf chuyen tam phao nhifng thtfc te da tiem an nhieu hiem hpa.
Theo sd lieu ciia Cue An toan lao ddng, Bp Lao ddng - Thifdng binh va Xa hdi (LD- TB&XH), xep hang sau tai nan lao ddng trong ITnh vifc xay dtfng la san xuat cd khi va dien giat. Ne'u ai da de'n lang nghe thudc xa Thanh Thuy, huyen Thanh Oai, Ha Ndi mdi tha'y ti le tai nan lao ddng trong ITnh vifc nay nhieu de'n mtfc nao. 80% dan sd trong xa lam nghe cd khi vi dao tao nghe d day kha ddn gian, chi I tuan la ai cung cd the trd thanh cdng nhan thanh thuc. Dieu nay cung da tao ra mpt tam li chii quan, nen chuyen 70% hd gia dinh lam nghe bi tai nan lao dpng d tay da khdng trd thanh chuyen thUdng dau ma thanh chuyen tam phao "ai bao khdng de y".
Mpt lang nghe khac ciia Ha Ddng, lang nghe Da Sy, Itfng danh vdi nghe san xuat dao keo cung cd nhtfng canh ngp tUdng ttf. Ttf sat thep thanh dao, keo cung cap cho ca Ha Ndi, cac tinh mien Bac, vUdt Qudc Id I vao de'n tan TP. HCM, hang cua lang nghe Da Sy di den dau cQng du'dc ngUdi tieu dung Ua chupng. Con dao, cai keo lam cho bd mat thdn lang dUdc ddi mdi nhUng cung lay di stfc khde cua nhieu ngifdi. Nhtfng vet seo dai tren nhtfng ddi ban tay, nhtfng lan bi bat mdng khdng tinh la thUdng tat, nhifng khdng ai dam khang dinh, nhtfng lan da ay se khdng bi cac benh da lieu. Khdng gidng n h u d Thanh Thuy, ban tay thie'u lanh Ian vi tai nan, d Da Sy, tai nan lao ddng chu ye'u anh hudng den mat. Nhieu ngifdi bi nd mat do chat sat bi ban vao, hay mat sat cung lam cho thi life giam nhieu, tham chi bi mu.
Nhufng de ndi chuyen phdng ngtfa tai nan lao dpng tai cdc lang nghe san xuat cd khi thi chang ai de y. Cung tich cifc tuyen truyen van dpng ngifdi dan phai gitf an toan trong lao dpng - san xuat nhifng vi nhieu Ii do ma viec nay van chifa thifc hien dUde mdt each quyet liet. Bd LD-TB&XH eung cd nhieu van ban ve van de nay nhUng quan trpng la y thtfc ciia ngUdi dan chifa cao. Hdn ntfa, vi la nghe san xuat thu cdng, ed may mdc nhifng hoat dpng chinh van la ban tay con ngUdi. ehinh vi the de san pham lam ra dep hdn, chuan xac hdn ma nhieu ngUdi khdng mang dd bao hd. Cd che xtf phiit dd'i vdi nhtfng cd sd siin xuiit thii cdng vi phiim cac quy dinh ve an toan lao ddng chtfa cao nen chifa mang day du tinh ran de.
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T A P C H i C d K H i V I E T N A M • So I n - rh.inv; H n.liii J
