cac dang 6 to tai che tao trong nudc kiem tra va danh gia cliat luong cum true

NGHIEN cuu-TRAODOI

Ap dung tieu chuan iso 1940-1:2003 |E|

kiem tra va danh gia cliat luong cum true cac dang 6 to tai che tao trong nudc

(*) TS. NGUYEN THANH QUANG ThS DO GIAO TIEN

TOM TAT:

Tieu chuan ISO 1940-1:2003 (E) 6Ua ra cac yeu cau ve chat lUOng can bang doi v6i cacrotocLfng lam viec 6 trang thai on dinh.Tieu chuan nay da du'dc sCrdung lam ccfsd cho viec thiet ke cac thie't bi can bang dang 6uac sCf dijng trong nhieu Imh vu'c cong nghiep nhu che tao canh quat, ro to, tuoc bin, true truyen dong...

Bai bao trinh bay viec ap dung tieu chuan ISO 1940-1:2003 (E) decan bang cum true cac dang tren thiet bj can bang ro to che tao trong nu'dc.

1. Md DAU

Trong khudn khd iing dung ket qua nghien ciiu khoa hpc cdng nghe vao thue tien san xuat, nhdm can bd ky' thuat thudc Cdng t\' COLOAMEC - Bd Cdng thuong, da thuc hien de tai nghien cim KHCN '^Nghien ciru thiet ke va cdng nghe ehe tao cum true cac dang truyen lire cua xe tai dudi 3 tan nang cao nang luc ndi dia hoa phu timg dtd", thue hien nam 2009. Nhdm de tai da sti dung cac ky thuat trong nghien ciiu khoa hpe de thiet ke, lira chpn vat lieu che tao, nghien ciiu tao phdi, gia cdng co khi ehinh xac, lap rap hoan chinh va kiem tra ky thuat.

Dd mat can bang ddng la mpt trong nhiing chi tieu danh gia chat lupng che tao cua cum true cac dang. Bai bao trinh bay ket qua nghien cuu trong viec ap dung tieu chuan ISO 1940-1: 2003 (E) de can bang ddng cum tnre eae dang va danh gia chat lupng san pham che tao tai dan vi san xuat.

2. CO SO LY THUYET CAN BANG DONG TRUC CAC DANG

2.1. Cdc dinh nghia

Theo eae tai lieu co sd. ta su dung cac dinh nghia ve can bang true cac dang gdm:

(*) Cdng ty COLOAMEC - Bd Cdng thuong

- Dgi luang mdt cdn bdng cua true cdc ddng: Khi ed mdt khdi luong u d each true quay cira true eae dang mdt khoang r thi dai lugng do luang mat can bang cua true cac dang la:

{\)d

=

u?

Trong dd: Vec to r cd gde la true quay va dinh la tam khdi luang u trong mat phang vudng gde vai dudng tam.

- Liec qudn tinh ly tdm: Khi true quay vdi van toe gde CO thi khdi luong u each true quay mdt khoang r se sinh ra lire quan tinh ly tam cho bdi cdng thiic:

(2) F = uco'r

- Cdn chinh mdt cdn bdng: La qua trinh thay doi phan bd lai khdi lupng cua true cac dang bang each them hoac bdt khdi lupng de lupng mat can b5ng bSng khdng:

Trong dd: u^ la khdi luang them vao hoae bdt di, r la ban kinh tinh tir tam khoi luang u den true quay eua true eae dang trong mat phing vudng goc vdi true quay.

Can Cli vao cau tao cua true cae dang, khoi luang them vao hoac bdt di cd the lay d nhieu vi tri, sao eho tdng hop lai thda man dieu kien (3).

De can bang true cac dang, tir thuc nghiem, ngudi ta thudng can bang tren 2 mat phang. Tren true eae dang co TAP CHI c a KHi VIET NAM V So 5 - Thang 5 nam 2011

the dupe chia lam nhieu dia mdng vudng gde vdi dudng true. Mdi dia mat can bSng duoc xac dinh bang mdt vec to f/. Vec ta f/ cd the phan tich thanh 2 vee to tren hai mat phang tiiy y (I va II) vudng gde vdi dudng true.

(Thudng dupe ehpn la cac mat phang d hai dau cua true cae dang). Khi cae lire ly tam F^ va f^^ eiia khdi lupng mat can bang da dupc phan tich ve 2 mat phang I va II thi tren timg mat phang, cae thanh phan lire nay ddng quy va tdng hop lai dupe hpp luc tren timg mat phang. Cac luong mat can bang U^ va (^ dupc tinh nhu sau:

(4)i^;

tS^gp'

±1

1=1

b

ry

S„co'-> d„ =

1=1

g, b n p

Cac lupng mat can bang U, va u^^ duac gpi la eae p p mat can bang quy udc. Ndi chung, ve lupng va goc thi cac vec to nay phu thudc vao vi tri cua cac mat phang can ehinh I va II.

Nhu vay, trang thai mat can bang cua true cac dang cd the md ta day dii bdi hai mat can bang quy udc trong hai mat phang ehpn tuy y.

Theo tieu chuan ISO 1940-1: 2003 (E) can bSng dpng true cac dang bao gdm 2 viee:

- Kiem tra mdt cdn bdng dw. Kiem tra lupng mat can bang du eua chi tiet quay xem cd nam trong gidi han eho phep hay khdng.

- Cdn bdng ddng: Neu lupng mat can bang du cua ehi tiet quay qua gidi han cho phep thi phai tien hanh can chinh phan phoi lai khdi luong de dua ve gidi han eho phep.

m

^

M

^

m

I

k |

1 =

'—-——___

M

'?Ci -*—1

1> \ G ~

" ^ ^ 9

ix 1^

, 1:

~ i

Hmh 1: Mo hinh dao dong cua true cac dang tren 6 do Md hinh nghien ciiu dao dpng cua true cac dang tren 6 do the hien tren hinh 1 [2]. Trong do, G la trpng

tam Clia true eae dang; M la khdi lupng true cae dang va m la khoi luong mat can bang (gia thiet m « M ) .

Gia su, hai dau miit ciia true cac dang rat gan gdi dd. Trpng tam G ctia true cac dang each hai gdi dd la 1^

va Ij. Gpi kj, k, la he sd dan hdi; c,, c^ la eae he sd can d hai gdi; x, cp la chuyen vi va gde quay ciia true cac dang quanh trpng tam G; x^, x, la ehuyen vi d hai miit dau true cae dang.

Su dung phuang trinh Lagrange II de thiet lap phuang trinh ehuyen ddng ddi vdi hai he tpa dp suy rdng (x, cp) hoac (x x,):

(5) dT_\_dT_ Qn _

Trong dd: T la ddng nang ciia he, n la the nang cua he, Q _ la luc suy rdng va q_ la tpa dp suy rdng tucmg ling vdi cae tpa dd x va ^ hoae x^ va x,:

2 2 ""^

The nang dan hdi ciia Id xo:

1

K-IJC-I ~r K-fJC-y

(7) ^(^1,^2) "2-1-^1

1 2 1

(8);r{x,(p) = -k,{x-l^<p) +-k^{x + l^(p) Cae lire ly tam do mat can bang gay ra cd the chuyen ve 2 mat phang can chinh (Gia su d 2 dau miit eua true eae dang) va ed thanh phan theo phucmg thang diing la Fj(t) va F,(t). Lue suy rpng ddi vdi tpa dp (x, (P) dupc xac dinh nhu sau:

(9)

Q, = -hF^ + hF. + {c,h -^A)^- i^Ji + cJl)(p

Ddi vdi cac tpa dp x^ va x, ta ed:

(10) 2x1 = ^ - ^1^1 Q.2 = ^2 - ^2^2

Bien ddi ta dupc he phucmg trinh md ta chuyen dpng eua true cac dang trong cac tpa dp suy rpng x va V nhu sau:

(11)

Afx+(c, +Cj)jc-(C|/, -c/,)(^+(^| +yx-(i|/| - V j ) p f , +f|

KM + Jr.

(12) /^ x\ + c{x.^ + ^,x, =F^ {t)

•^•^~i -^x +- 2—-x^+c^x^+k^x, =F2{t)

NGHIEN CUU - TRAO OOI

Cac he phuang trinh (11) va (12) la dang md ta dao dpng cua true eae dang theo 2 he tpa dp suy rdng (x, 9) va (Xj, X.,) dupc lam ea sd de xae dinh cae phuang phap can bang true cac dang.

1.2 . Phu-ffng phap can bang true cac dang:

Phuang phap da dupe dua ra bdi cac tac gia Rieger (1982) va S.Rao (1983) [2], vdi viee dimg khoi lupng thii de xae dinh eae he sd anh hudng trong viec tinh toan chinh xae dp Icin va vi tri eua khdi lupng can bang cho mdi miit ciia true cac dang khi do dupc dao ddng mat can bang ban dau. Chang han, do dupc dao ddng ban dau tai d true I la OA, vdi bien dp OA va gde pha (P/i. Tai o true II tuong irng la OB va gde pha (PB- Cae vec to OA va OB' do dupc khi gan khdi luong thii m^

vao mat phang can bang tai niit I. Bieu dien chiing tren toa dd cue hinh 2.

(14) a,:

Hinh 2: Sa do vec ta bieu dien mat can bang tren true cac dang

Nhu vay, vee to AA' va BB" la dao ddng sinh ra do khdi lupng thir m^, cae pha dao ddng tuong iing la eae gde V'AA' va VBB: Dp Icm cua cae vec to AA va BB' ciing nhu cac gde V.AA' va VBB' xac dinh dupe thdng qua cac phep bien doi luang giac.

Cac he sd anh hudng lien he cac dao ddng d hai milt I va II khi dat khdi lupng thti m^ tai mat phang I dupe cho bdi edng thue:

AA' BE'

; o^i = —

Trong dd: a^ dupe gpi la he sd anh hucmg iing vdi mdt don vi khdi luong dat tai mat phang j (d day j =1), gay ra vee to dao ddng tai mitt I (d day i=l ddi vdi miit I va i=2 ddi vdi miit II). Cae sd hang aj|Va a,j deu la cac sd phirc vi chiing dupe bieu dien dudi dang vee to.

Tuang tu nhu \a\, he sd anh hudng tai eae mitt khi ta dat khdi lupng thu m, vao mat phang can bang II se la:

(13) «i

(17)

72_ = « 1 1 « 2 1 021*^22.

Tir dd tinh dupe:

(18) =

AA" BB"

; Oi2= — OTj m^

Mdt each tdng quat, dao ddng do dupe d miit I la dao ddng do khdi lucmg mat can bang d mat phang I va mat phang II gay ra. Neu vee to dao ddng V, dupe sinh ra d miit I do them khdi luang m^ vao mat phang I va m., vao mat phang II thi:

(15)f^i =a,,OT,+fif,2n72

Tuong tu, vec ta dao ddng V, dupe sinh ra d miit 11 do them khdi lupng m^ vao mat phang I va khdi lupng m, vao mat phang II la:

(15)^2 =a2,/Wi +<322'"2 Viet dudi dang ma tran:

Nhu vay, de can bang true eae dang thi ban dau can dua vao cac vee ta dao ddng AO va BO d miit I va miit II tuang ling. Do do, neu ta lay Vj=AO va V.,=BO la cac gia tri do dupc khi khdng ed khdi lucmg thu, thi khdi luong can bang chinh la nghiem m^ va m, eua phucmg trinh. Cac sd hang Vj, V,, m^, m^ deu la sd phiic. Dp ldn cua vec ta mj va m, xac dinh dd Icm khdi lupng can dap them vao, cdn gde pha eiia ctia vee ta m^ va m2 xae dinh vi tri khoi lupng thu trong mat phang can bang. Nhan thay ddi vdi cimg loai true cae dang thi he sd anh hucmg a se khong thay ddi eho he gdi dd da ed nen khi can bang ddng, ta khdng can phai dimg khdi lupng thii niia, ma chi can do mdt lan ta tun ra dupc khdi lupng va vi tri mat can bang.

3. MOT SO KET QUA CHINH TRONG NGHIEN CUtJ THIET KE VA CHE TAG TRUC CAC DANG CUANHOM

N G H I I N

CUtJ

Theo eae yeu eau dat ra cho nhdm can bd ky thuat, tai Cdng ty COLOAMEC da hoan thien viec nghien ciru thiet ke va ehe tao cum true cac dang d td tai 3 tan.

Ket qua cho thay, edng nghe eiia de tai hoan toan ed the nhan rdng de san xuat loat sii dung eho cac d td lap rap trong nude. Mdt sd ket qua chinh gom:

J TAP CHI c a KHI VIET NAM V So 5 - Thang 5 nam 2011

- Xac dinh dupe vat lieu goc va dae tinh ben eua chi tiet eae true cac dang mau Han Quoc, Trung Qude, Nga:

- Nghien ciiu tdng quan ve ket cau cum true eae dang, eae true cac dang mau;

- Thiet ke theo mau cum true cac dang cua xe tai 3 tan LF3070G1 dang dupc san xuat va lap rap trong nudc;

- Tinh toan kiem nghiem ben de thiet ke phu hop vdi edng nghe ehe tao trong nudc;

- Xa}' dung quy trinh cdng nghe che tao eae ehi tiet chinh nhu than cac dang, nang cae dang, khdp chii thap (bao gdm cdng nghe tao phdi, gia cdng co, nhiet Imen);

- Xay dung quy trinh cdng nghe lap rap hoan chinh cum true cac dang;

- Xay dung quy trinh cdng nghe kiem tra chi tiet va tdng the cum true cac dang;

- Che tao eae ehi tiet chinh va cimg vdi eae chi tiet tieu chuan nhap ngoai (d bi, vdng phcit...) de lap rap hoan ehinh cum true cae dang dat yeu cau ky thuat.

- Lap rap tren xe va ehay khao nghiem.

(b) Cac chi tiet gia cong cac dang

(c) Lap rap cmn true

Hinli 3: Cum true cac dang tlri^t ke va che tao trong nudc

4. KIEM TRA TRUC CAC DANG

4.1. Gidi thieu tieu chu§n ISO 1940-1:2003 (E) Tieu chudn ISO 1940-1: 2003 (E) Mechanical

vibration - Balance qualit> requirements for rotors m a constant (rigid) state: Part 1- Speciiication and verification of balance tolerances.

Phgm vi img dung:

Tieu ehuan ISO 1940-1: 2003 (E) dua ra cac ehi tiet ky thuat ddi vdi cac rd to dupe coi la cimg va lam viee d trang thai dn dinh. Tieu chuan na\- chi rd:

+ Dung sai can bang;

+ Sd lupng cae mat phang can thiet de hieu ehinh can bang;

+ Cac phucmg phap xae dinh khdi lupng mat can bang.

Tieu chuan ciing dua ra cac ldi khuyen lien quan tdi cac yeu cau ve chat lupng can bang theo loai ehung loai va tdc dp lam viee eua cac rd to dupc eoi la cimg va lam viec d trang thai dn dinh.

Casa todn hoc ciia ISO 1940-1:2003 (E)

De thda man dieu kien van hanh ciia rd to thi lupng mat can bang du U,.^^ khdng nen 1cm hon gia tri lupng mat can bang du eho phep ^P^,-, nghia la U,.^^ < U^^,..

Nhin chung, ddi vdi eae rd to hoac cae ehi tiet dupe xem nhu rd to thi lupng mat can bang du cho phep U..

ti le vdi khdi lupng cua rd to, tii' dd, dua ra gia tri luong mat can bang rieng du eho phep dupe xae dinh bdi:

{l9)e^^,.=U^^,./m

Thuc nghiem chi ra rang, ndi ehung luong mat can bang rieng du eho phep thay ddi ti le nghich vdi tdc dp quay eiia rd to.

(20)e^.,. ~ 1 / "

Mdt each khae, mdi quan he na>' dupc eho bdi phuang trinh (21), trong do, Q la van tde gde eiia rd to a tde dd lam viec cue dai:

(21) e^erf^ = constant

Mdi quan he trong phucmg trinh (21) la eo sd phan loai cac cap dp chat lucmg can bang G dupc the hien ducii dang dd thi (hinh 4 (a) va (b), trong dd, cap ehat • lupng G16 dupe ting dung de xac dinh cap chat lupng ddi vdi true cae dang, eae ehi tiet may ep. may ndng nghiep, bam bim than, eae cum tdng thanh rieng biet cua ddng ea eho d td, xe tai, dau may xe lua. true khuyu ddng CO tu 6 xi lanh trd len vdi nhiing \ eu eau dae biet.

Dd thi cho phep xac dinh cap chat lupng can bang theo lupng mat can bang du eho phep ^p« a toe dp lam

\"iec 1cm nhat. f:^

NGHIEN CUU - TRAO OOI

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Hinh 4: Do thi luong mat can bang neng con du cho phep phu thuoc vao cap chat lupng can bang G \'a toe dp qua> (Nguon ISO

" 1940-1:2003)

4.2. LTng dung ISO 1940 -1: 2003 (E) kiem tra true cac dang de tai ch8 tao

Can bang true cae dang la can bang cac khdi lupng lech tam trong chuyen dpng qua\' nham giam dupe cac rung ddng ya tai trpng tren cac khcip ndt. Viee can bang dupe tign hanh theo tieu chuan ISO 1940-1:2003 (E).

True eae dang dupe can bang trong 2 mat phang. yeu cau cap chat lupng can bang G16.

T/iiet bi do

Viee can bang ddng cum true cac dang dupc thuc hien trong phdng thi nghiem tren thiet bi can bang rd to dai NOVICO-BLOl do Vien Co hpe Viet Nam nghien ciiu thiet ke \'a ehe tao.

Thiet bi dupe ehe tao dua tren ca so ly thuyet la phuang phap he sd anh huong de xae dinh lupng mat can bang, phucmg phap na>' eiing da dupe dimg pho bien trong cac phan mem can bang rd to trong mpt. hai hoac nhieu mat phang.

Thiet bi gdm 3 phan ehinh:

- Phan tru} en ddng ca khi vdi ddng eo dan ddng 3 pha (cdng suat 1.5 kW, n^^^ = 1450 \/p) \ a bien t4n dieu khien tdc dp:

- Phan do ghi tin hieu;

- Phan mem thu nhan \a xu ly tin hieu Das} Lab 9.0;

- Phan mem can bang Balance - X3 cd nhiem \'u xu ly tin hieu do duoc tir phan cirng. tinh toan \ a chi ra lupng can bang can thiet.

Thiet bl NOVICO-BLO1 cd the can bing loai rd to dai (cd chieu dai ldn hon dudng kinh tdi thieu 1,5 lan) vdt cac thdng sd gidi han eua rd to nhu sau:

- Chieu dai: L = 3 m. L = 0.4 m;

ma.x ' mm

- Dudng kinh: D = 1.3 m. D = 0.04 m;

^ max mui

- Khdi luona: m = 1500 kg. m = 5 kg.

*- max ^ mm ^

4.3. Can bang dong cum true cac dang che tao Idp dgt mic cdc ddng

True cac dang can bang

Hinh 5: So do Ihiet bi can bang true cac dana NOVICO-BLOl

TAP CHi c a KHi VIET NAM V So 5 - Thang 5 nam 2011

Khi true cac dang chm en ddng qua\' thi lire quan tinh sinh ra do mat can bing se tae dung lire len khung be thu. khung rung dpng se lam eho la thep dan hdi rung ddng. Hai eam bien chu>"en \ i dupe gan Midng gde vdi mat phang la thep tai hai dau eua gia do true cac dang de do true tiep chuyen vi cua la thep khi nd rung ddng. Cac cam bien nay duoc ket ndi vdi phan ciing, phan cimg dupe ket ndi vdi phan mem thu nhan va xii ly tin hieu DasyLab 9.0 cai dat tren ma\ tinh, do va>', dii lieu ve gia tdc rung ddng va chuyen vi dupc thu nhan va xir ly ngay tren ma> tinh thdng qua phan mem.

Quy trinh do

Viec can bang ddng true cac dang dupe tien hanh 5 budc:

Budc 1: Tien hanh do xae dinh chuyen vi tai cac gdi do hai dau true cac dang d mdt tdc dp quay nhat dinh.

Budc 2: Gan khdi lugng thu len mat phang can bang phia trai true cac dang, tien hanh do xac dinh chuyen vi tai eae gdi dd hai dau true cae dang d tde dp quay nhu bude 1.

Budc 3: Gan khdi lupng thti len mat phang can bang phia phai true eae dang, tien hanh do xae dinh chuyen vi tai cac gdi dd hai dau true cae dang a tde dp quay nhu bude 1.

Bude 4: Su dung phan mem Balance - X3 vdi cac thdng sd dau vao d cac bude 1, 2 va 3 de xae dinh cac lupng mat can bang (dp Icm va gde pha) tai hai mat phang can bang.

Budc 5: Gan cac khdi lupng can dap them (khdi luong bang vdi lupng mat can bang nhung ngupe pha 180° so vdi vi tri lucmg mat can bang) vao de true eae dang, do kiem tra lupng mat can bang du, so sanh vdi miic cho phep ciia tieu ehuan de danh gia cap chat lupng can bang.

• ' ^ # V

x '

t-!«w<WB'v''^

< ^^^ir^

IQII^X ^ "^LM

Vi tri va khoi luong dip them vao dau phai true cac dang Hinh 6: Vi tri \ a khoi lugng dap them Cdc ket qud do

\ A A A A A /A A

V v A' v A' ^' •-•'

/

Pha va mirc rung dpng (chuyen vi) tai hai gpi true cac dang truoc Ichi can bang

Vi tri va kh6i lupng dap them vao dau trai true cac dang

Pha va mirc rung dpng (chuyen vi) tai hai goi true cac dang sau khi can bang

Hinh 7: Ket qua do chuyen vi va pha dao dpng tren true cac dang

Dudng 1: Dd thi pha cua true eae dang quay;

Dudng 2: Chuyen vi dau trai Dudng 3: Chuyen vi dau phai

Bang 1: Chuyen vi tai hai dau true cac dang tren thiet bi can bang

(Xem tiep trang 48)

NGHIEN CUU - TRAO OOI

doan he thong nap luu lupng vao binh tieh thiiy luc.

Chinh vi ^'ay. trong trudng hpp ly tuang, diiu kien cdn se la:

' i

(i) f [ 2 ( 0 - 2 ; , } ^ ' ' = 0 (4) - Lupng dau can cap them chd he thdng tir tram binh tieh can bang vdi lucmg dau tram bom cd the nap cho binh tich trong mdi chu trinh tj.

(h) Z {[2(0 - a Ja'? = A1" ( 5 ) . Luang dau tram binh tich ed the cap AV ludn can bang vdi the tieh dau ma tram bom ngudn cd the nap cho binh tich trong mdi chu ky tj.

Xac dinh liru lirccng t r a m bofm nguon: Bieu dd luu lupng tire thdi eua cac CCCH (hinh 1) trong he thdng ludn cd the xac dinh tren co sd dii lieu cd dupe tir quy trinh edng nghe. Tir dieu kien can (4) va bieu do luu lupng, ta cd the xac dinh luu lupng Qi^ cua tram l^am ngudn can chpn theo cdng thire:

( 7 ) Q , = F\]Q{t)dt

0

Xac djnh dung lircmg tram binh tich: Trong mdi ehu trinh boat ddng tj cua he thdng, qua trinh xa va nap Clia tram binh tieh phai can bang the tieh de eudi chu trinh tram lai ve trang thai no ban dau. Lupng dau tram can cap cho he thdng AV dupc xac dinh tir dieu kien (5). Dung lupng binh tich ed the xac dinh dupc theo edng thirc:

(8)v =Av/(p„,,p,;"-''-(p„p^;"-^

Trong dd: V^ - Dung tieh tram binh tich can ehpn;

Pg - Ap suat nap ban dau cua khi tro nito nap vao binh tieh; p^ - Gidi han ap suat xa eiia binh tich; p, - Gidi ban ap suat nap cua binh tich.

KET LUAN

Tren thue te, de bii lupng dd ri trong he thdng va cd he sd an toan khi hoat ddng, luu lupng tram bam ngudn Qj^ va dung lupng tram binh tieh V^ xac dinh theo (7) va (8) can dupc chpn ldn hon tinh toan

10-20%. •:•

Tai lieu tham khao:

[1] BASTATM -HYDRAULIC DRIVE . MOSKVA-1969.

[2] Basic Principles and Components of Fluid Technolog}- RudiA. Lang Mannesmarm Rexroth GmbH 1991.

(Tiep theo trang 43)

Gia tri lon nhat (max) Gia tri trung brnh binh phuang (RMS)

Tnroc khi can bang Dau ben

trai 0,5904 nun

0,3190 mm

Dau ben phai 0,9806 nrni

0,6385 mm

Sau klii can bang Dau ben

ti'ai

0,2740 nun

0,1489 mm

Dau ben phai 0,2881 mm

0,1534 mm

Ddnh gid: Ket qua can bang ddng true cae dang dat cap chat luong can bing G16 (ISO 1940-1: 2003) eho thay, mirc rung ddng cua true cac dang tai hai gdi dd dau ben trai va ben phai da giam di rd ret sau khi dupe can bang ddng.

- Tai gdi trai true cac dang, gia tri muc rung ddng ldn nhat giam hon 2 lan tir 0,5904 mm xudng 0,2740 mm va mirc rung ddng trung binh eiing giam hon 2 lan tir 0,3190 mm xudng 0,1489 mm.

- Tai gdi phai true cac dang, gia tri mtic rung ddng Icin nhat giam hon 3,4 lan tu' 0,9806 mm xudng 0,2881 mm va miic rung ddng trung binh ciing giam hon 4 lan tir 0.6385 mm xudng 0,1534 mm.

5. KET LUAN

Tieu chu4n ISO 1940-1:2003 (E) da dupc ap dung de kiem tra danh gia dp mat can bang true quay noi chung va true cae dang d td trong ehe tao mdi hoac sua chiia thay the. 0 Viet Nam ehua ed che tao true cac dang d td, qua bao eao nay nhdm tac gia mudn gidi thieu viec kiem tra cap chat lupng can bang cum true cae dang dua theo tieu chuan ISO 1940-1:2003 (E) la hoan toan phil hop va cd the ap dung trong san xuat loat, gdp phan nang cao nang lire ndi dia hda edng nghiep che tao phu tiing d td trang nude, "l*

Tai lieu tham khao:

[1] ISO 1940 -1 (E): Mechanical vibration - Balance quality requnements for rotors m a constant (rigid) state. Part 1: Specification and verification of balance tolerance.

[2] GS. TSKH Nguyen Cao Menli, Bdo cdo khoa hoc di ldi cdp lien "Nghien cim, thiet ke, che tqo thiit bi ca dien tie cdn bdng Roto ddr. 2008.

[3] GS. TSKH Nguyen Cao Menh, The balancing of rotating machinery as nonlinear system, Vietnam .Journal of Mechanical Volume 2 LNo-3,pp 165-172.

[4] Hatto Sctme\der, Balancing Technology, Schnenck 1991, [5] J.S.Rao, Rotor dynamic, New York, 1988.

m

So 5 - Tliang 5 nam 2011