KHOA HOC - CONG N G H f 62n/imVI?nKhoahQciKtCdngngh4GTVT
Mot so van de trong nghien ciru thiet ke, che tao thiet bj thCr moi cap
• ThS. DUONG QUANG TRONG; TS. NGUYEN VAN THjNH Viin Khoa hoc va Cdng nghe Giao thdng van tdi
TOM TAT: May thii moi cap dupc che tao trong nganh cong nghiep phat tnen, vgt li^u dgc bi#t, thiet bi hien dai, cong nghe tien tien ma tat ca nhQng dieu do deu la nhung diem yeu Ion cua nganh co l<hi che tao nuoc ta hien nay, neu thiet ke che tao may thd moi cap hoan toan theo mau ci!ia nuac ngoai se kho khi thi hoac hieu q u i kinh te thap Bai bao neu mot sd van de trong cong tac thiet l<e va cong nghe che tao thiet bi thd mdi cap phij hop VOI nguon vat tu va trinh dp cong nghe che tao trong nuoc
T O K H O A : Thiet b| moi, che tao.
ABSTRACT: The steel strand fatigue testing equipment is manufactured in a developing industry with special materials, advanced equipment and state of the art technology, however all these things are the main weaknesses of the mechanical engineenng industry in our country nowadays, if the designing and manufacturing process of the steel strand fatigue testing equipment are completely following to foreign form, then it would not be feasible or low economic efficiency The article shows some problems during designing process and manufacturing technology of steel strand fatigue testing equipment which is suited for material sources and technological level in our country
KEYVi'GRDS: Equipment fatigue, make
1.DATVANDE
d nude ta hien dang SLfdyngea hai loai eau treo day vdng va cau treo day vang. Xu hUdng hien nay, vdi nhdng cdng trinh cau Idn, sd cau treo day vang dUoe thiet ke va thi cdng mdi ngay mdt nhieu nhU: Cau Nhat Tan, cau My Thuan, cau Can Tho, eau Bai Chly, eau Rach Mieu... Ddi vdi cle cdng trinh cau treo nhd thi sd lupng eau treo day vdng duac thiet ke va thi cdng mdi nhieu, dien hinh la dU I n 186eau treo dan sinh.
Ddi vdi he cau day, he dly chiu lUc la chu yeu vdi tinh chat tai trong ddng do t i e ddng cua gid, cua hoat tli...,
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do vay kha nang chiu mdi eua e l p cd vai trd quan trpng trong viee thiet ke, thi cdng va khai thae,
Nham kiem soat chat Iuong cap trudc khi dua vIo lap dat, sCr dung thi can phai kiem solt chat luung rat ehat che, t d vat lieu dau vao, quy trinh san xuat, b i o dudng, kiem tra san pham eudi cung. De ed the thi nghiem mdi cho cap eau treo, cac dcrn vj phai dUa ra nude ngoai de thi nghiem gay lang phi tien eua va I n h hUdng nhieu d^n thdi gian thi cdng cdng trinh. Mat khIc, eae thiet bi thCr nghiem hien dai hien nay eua elc nude ed nen cdng nghe tien tien tren the gidi deu cd gia thanh rat cao, viee mua sam cac thiet bi nay ddi hdi lUPng kinh phi Idn va khdng t h u i n tien trong viee sda chUa, bao dUdng, thay the vdi trinh do cdng nghe trong nUde.
Hien nay, ehua ed nhdng nghien cufu, che tao trong nUdc cle thiet bi phuc vu cdng t i e thd nghiem kha nang chiu mdi eua cap dung eho he cau day. Vi vay, van de nghien edu thiet ke, che tao thiet bi thd mdi cap trong nude la mdt de tai cd tinh thue tien, mang lai hieu qua kinh te - ky thuat va xa hdi.
2. C Ac T H I I T Bl THUf M O I T A VET TR^N T H I G1(5|
Tren the gidi. thiet bi thd mdi cap thep dng lUc da duoc cle hang che tao thiet bj thi nghiem nghi&n culi va sin xuat t d lau, eCing vdi su hoan thien ve tieu chuan d i n h g i l , quy trinh kiem tra nghiem thu, sU phIt then cua ky thuat do, dieu khien, vat lieu che tao elc hang che tao lien tue eli tien cho ra eae thiet bi ngay eang hien dai, do dupe nhieu thdng so phuc vu cho qua trinh kiem tra danh gia chat luang cua elp thep dU dng lUc
a) - Jhiit bi cua hang Pfeifer Seil-und Hebetechnik
KHOA H O C - C O N G NGHE
So 10/2018
c) - Thiet bl cua hang MTS
d) - ThiSt bj cda hang Balroe
Mdt sd hang che tao mIy nude ngoai da che tao nhieu mIy thCf mdi elp cd tai trpng khac nhau, trong do ed eae may ed t l i trong Idn du de thd mdi c l bd d p cd t l i trpng hang chuc va tham chi len tdi hang tram tan. Tuy nhien, eae thiet bi nay cdng kenh va rat dat tien, it sCf dyng. Trong khi dd, hien nay thiet bj thd mdi cap soi dOn lai dupe dung rat phd bien. De thuan Idi va gilm g i l thanh khi thi cdng, bd d p he cau day duoc che tao lap dat ngay tai cdng trudng t d cac tao d p che tao trong nha may cd dUdng kinh 12.7mm - 15.2mm. NhU vay, thay vi phai thCf mdi ea bd cap cd t l i trpng Idn, ngudi ta tien hanh thd mdi tao elp nhd.
Nhin ehung, cac hang ndi tieng tren the gidi che tao thiet bi thCr mdi d p chuyen dung, vdi mdc do hien dai hda cao, ket ndi mIy tinh dieu khien t u ddng chu trinh kiem tra theo tieu ehuan, do chinh xac va dp dn dinh cao.
Tuy nhien, gia thanh thiet bi rat dat, ben canh dd thiet bj nhap ngoai phy tung thay the khdng ed san, thdi gian nhap khau lau gay khd khan trong cdng t i c sCfa ehda, b i o dudng, day la ly do ma den nay nude ta chUa ed don vi nao cd thiet bi thd mdi e l p ddng bd eua nUdc ngoai.
3 . T H l f T B ! T H L r M 6 i C A P T H | g T K e , C H e T A 0 T A I VIET NAM
d nUde ta, trong nhieu nam trude day do nhu eau kiem tra dd ben mdi eua vat lieu ndi ehung va dp ben moi eua d p ndi rieng edn ehua cao nen ed rat it ddn v; sddung
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K H O A H O C - C 6 N G N G H f - 62niimVt^KhoahQcvACdngngh^GTVT
mIy thd mdi. Hien tai. Vien Khoa hoc va Cdng nghe GTVT dang cd mdt may thd mdi cua hang MTS la SilentFlo cd tai trpng nhd va da khdng sddyng nhieu nam, eung la thiet bi dUdc mua tCr nUde ngoai. Vai nam gan day, eung vdi sU phat tnen eua nganh GTVT, cle cdng trinh eau treo da duac sit dung nhieu. De d i m bao chat lupng cdng trinh thi viec thi nghiem dd ben mdi cua d p dUOc d c ddn vi thiet ke quy djnh trong ehi dan ky thuat. Nhin thay nhu cau thCf nghiem dd ben mdi cua d p su" dung trong nude dang cap thiet, Trung tam Cdng nghe May xay dung va Co khithuc nghiem thude Vien Khoa hoc va Cdng nghe GTVT dang tien hanh nghien edu, che tao thiet bi thCf mdi d p chuyen dung.Thiet bj nay cd khi nang kiem tra die tinh mdi eua d p phu hop vdi quy dmh trong elc tieu ehuan nhU:
TCVN 7937-3:2009 (ISO 15630-3:2002). Thep dung lam edt be tdng va be tdng du dng luc. Phuong phIp thd;
Phan 3;Thep dU Ung luc.
TCVN 6284-4:1997 (ISO 6934-4:1991). Thep edt be tdng du dng luc - Phan 4: Dinh.
22TCN 272-05 (AASHTO LRFD). Tieu chuan thiet k^
cau (Bridge Design Specifications).
TCVN 10952: Cap du Ung luc bpc epoxy tdng sdi don.
Gidi thieu ve thiet bi thd mdi d p :
1 - Loadcelt 2 - Xi-lanh thijy lye: 3 - Nip bao ve:
4 - He thong dieu khiin, 5 - Miu cap kiitn tra: 6 - He kt^ung miy.
7 - Neo giU cip. 8 - Bq nguon thuy lye Hinh 3.1: Tbiit bi thi nghiem mdi cap dirung Iue Cle phep thd thi nghiem ben mdi d p ; Sau khi dieu khien eho xi-lanh t i c dung gia tri luc len d p theo quy trinh thCr nghiem, eho he thdng gay rung hoat ddng, dieu ehinh tan sd, bien do, luc rung ddng theo quy trinh.
He thong thCr mdi bat dau tam viec, tren man hinh hien thi d e thdng sd thd nghiem bao gdm: Bien dp luc thd nghiem, tan sd thd nghiem, sd chu ky da thUc hien, thdi gian da thCr nghiem, thdi gian du kien ket thuc, bieu do dao ddng cua Iue theo thdi gian. Sau khi dat ehu ky thd nghiem theo yeu cau, tat ngudn gay rung, dung ngudn da nang nang piston len de tien hanh do dae d c thdng sd theo yeu eau eua quy trinh thd nghiem.
Phan mem dieu khien cd khi nang luu gid sd lieu khi mat dien, ghi lai toan bp cle sd lieu trong sudt ca qua trinh thi nghiem, xuat ket qua b i o d o sau khi ket thuc, cinh bao khi d c sd lieu thi nghiem cd dau hieu bat thudng...
Thiet bi thd mdi cap da duac nghien cdu, thiet ke, che tao taiTrung tam Cdng nghe May xly dung va Co khi
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thue nghiem. Qua qua trinh kiem tra, chay thCr, thiet bi lam viec tdt, dap dng eae yeu cau ky thuat dat ra.
4. M O T S 6 V A N Oi TRONG TfNH T O A N , THlgj K£,CH^TAO
4.1. Gidi phap thi^t ke he thuy lac gSy rung ddng Thiet bj thd mdi eCia nude ngoli sin xuatthudng diing van thuy lUe servo (Hinh 4. la) de dieu khien tan sd, bien do eua Iue tae dung len ta vet. Mach thuy lUe dung van nly cd cau true dan giln nhUng gia van servo lai rait d i t , che dp b i o dudng sda chda khat khe, tinh trang ky thuat eCia van Inh hudng rat Idn d^n q u i trinh dieu khien t l i trpng lap, do vay sau mot thdi gian sCf dung van nay phli thay the gay tdn kem. Mat khac, do dung van servo dieu khien ddng diu d i o chieu vdi tan sd cao, lien tuc nen chit Idng cdng tie bi ndng len rat nhanh, thudng he thuy lUc can cd he thong lam m i t ed nang Iue trao ddi nhi^t Idn, ket eau toan he trd nen cdng kenh, lam viee thudng g l y tieng dn Idn.
b - H0 thuy luc gay rung dS xuat Hinh 4.1: He thdng thuy luc giy rung
KHOA H O C - C O N G N G H £
So 10/2018
De tai de xuat phuong an he thuy lUc gay rung nhu Hinh 4. lb: Bd ngudn thuy lue da nang 7 cd vai trd dieu chinh xi-lanh thuy lUc chuyen ddng Tien - Lui, vi ehinh lUc thd nghiem dat soi cap. Ngoai ra, bd ngudn nay edn cd tac dung nap day dudng dng va bd sung chat Idng cdng tactrongsudt q u i trinh thd tmh hole thd mdi.
Bo ngudn thuy luc tao lUe ddng 12 dupe dan ddng bdi md to dien cd the dieu ehinh dUOc toe do vdng quay b§ng bien tan, bd ngudn nay lien tyc tao ra cac ddng dau d I o chieu t i c dung len xi-lanh thuy lUc 4. De dieu ehinh bien dd dao ddng ta chi can dieu ehinh van can b i n g 11, khi van can bang 11 ddng het bien dd dao ddng eda piston la Idn nhat, khi md dan van can bang 11, mdt phan dau do bg ngudn thuy lUc tao lUc rung ddng 12 se duac tieh vao trong van can bang 11. NhU vay, lUu luong dau dua den xi-lanh thuy lUe 4 g i l m di, hanh trinh lam viec piston g i l m , bien do dao ddng g i l m , lUc t i e dung len spi cap cung g i l m theo. Binh tich ap 2 dap tat xung dao ddng l p suat trong he, binh tich ap 9 cung vdi bd ngudn thuy lUe da nang t u d d n g nap bd xung chat long vao he khi ed bat ky rd ri nao.
Neu trong q u i trinh dieu chinh van tiet lUu vao khdng ehinh xac, ap suat trong he tang len vuat q u i ngUdng cho phep cd the lam p h i huy mau thCr hole lam sai lech ket qua thi nghiem, van tran 6 se lam viee de khdng che bien dd dao ddng Idn nhat va lUc t i e dung Idn nhat len soi cap.
Van mdt chieu dieu khien 10 cd t i c dyng ngan each mach thuy lUc tao lUe rung ddng khi thd mdi vdi bd ngudn thuy lUc da nang, dong thdi nd nap bu dau bo sung khi cd sU rd ri dau trong mach gay rung khi lam viec.
CIm bien l p suat 3 chuyen gia trj ap suat trong he thdng thuy lUc thanh tin hieu dien, dua ve he thdng xd ly, phan tieh dQ lieu thi nghiem. Cam bien Iue Loadeell do va hien thj tUe tac dung len soi d p .
4.2. Giai phap dieu khien tan so rung dong 6 elc may thCr mdi elp eua nude ngoai, tan sd dao ddng dUOc dieu khien bang xung dien, tan sd dao ddng d n g cao thi che dp lam viee cua van servo eang kh3c nghiet do lien tue p h l i ddng ngat ddng dau ap suat cao.
MIy thCf mdi d p che tao trong nude dieu chinh tan sd dao ddng rat de dang bang clch thay doi tdc do vdng quay ddng cO dan ddng xi-lanh tjnh tien 1 (Hinh 4.1b).
Tren thi trUdng nUdc ta cd sin d c loai bien tan thdng dung, gia re va boat ddng tin cly, day la mdt trong d c yeu td de mIy che tao tai Viet Nam ed g i l thanh ha ma van dam b i o yeu cau ky thuat de ra.
4.3. GiSi phap dieu khien bien do liic rung dong Trong may thd mdi d p eua nude ngoai, bien dd dao ddng cua lUc dUOc kiem soat qua sensor ap suat, sensor l p suit dua ra gia tn l p suat thUc, bp xd ly se dieu chinh tin hieu dien eho van servo md, khep hole ddng hoan toan de khdng che luang dau vao xi-lanh cho phii hop.
Nhu vay, van servo lam viec yeu cau p h l i ehinh xae va rat tin cay, he thong thuy lUe dUoc bao dUdng thudng xuyen, ehi can cd chut can ban cung dan den sU lam viee khdng binh thudng eua van servo, lam Iue dat len soi cap vUpt qua gia tri quy dinh ed the lam ddt cap.
Ta thay rang, thiet bj eua nude ngoai tuy rat hien dai nhung gia thanh cao, ddi hdi che dp bao dudng khat khe, phu tung thay the chinh hang, cdng tae sda ehda, b i o dudng gap khd khan.
Van de nay da duoc nhdm thuc hien d ^ tai nghien cdu g i l i quyet rat hieu qua nhu sau: Trong mach thCiy lUc tao rung (Hinh 4. lb), gia trj l p suat Idn nhat dUOc khong che bdi van tran 10, g i l trj ap suat Idn nhat dUde khdng che bdi van tran 7, de bao ve van tran khdng p h l i l l m viee thudng xuyen do eae xung ddng l p suat ta dung binh ac quy thCiy lUe 3 va van tiet lUu 2, van tiet lUu 2 duae dieu chinh de lUOng dau thda dUac tich vao k quy thuy Iue ma khdng p h l i xa qua van tran 10.
5. K I T L U A N
Vdi quan diem phat huy ndi lUc, tan dyng nhdng tiem nang sin cd trong nUde, tiet kiem ngudn ngoai te tdi da eho Nha nude, hien dai hda cac thiet bj thi nghiem kiem tra phye vy nganh GTVT,Trung tam Khoa hpe cdng nghe May xay dung va Cd khi thuc nghiem ludn ludn eoi trgng viec Ung dung nhdng tien bd khoa hoc cdng nghe, fim nhdng giai phIp k h i thi ap dyng vao ITnh vUc may thi cdng ndi chung, thiet bi thi nghiem kiem tra ndi rieng nham dap dng nhu cau cCia sin xuat ngay eang cao theo sU phat trien cua dat nude. Viee ap dung nhdng g i l l phap trong thiet ke, che tao da trinh bay tren day gdp phan che tao thanh cdng cle thiet bi thi nghiem kiem tra trong nude, phye vu kjp thdi va ed hieu q u i cho d c cdng trinh GTVT.
Tai lieu tham khao
[1]. TS. Nguyen Xuin Khang (2001), Nghiin cUu nhCtng gidi phdp khoa hoc cong nghe thiet ke che tgo cdc thiet bi thi cdng chuyen dung cdng trinh GTVT, Tuyen tap bao elo tai Hdi nghi Khoa hoe nhan ky mem 45 nam thanh lap Vien KHCN GTVT 1956 - 2001, Ha Ndi.
[2]. TS. Nguyen Van Thinh (2015), Nghien cdu thiet ke, che tgo may thir thiy mdi ta vet be tong cot thep duUng ldc phuc vu sda ehda ndng cap he thong dUdng sdt Viet Worn,Detai KHCN cap Bd.
[3]. KS. DUdng Quang Trong (5/2018), Nghien eUu Ddng lUe hoe he thdng truyen ddng thuy lUe eCia thiet bi thd mdi cap dung cho he cdu day, Luan an Thae sy.
Ngay nhan bai: 20/8/2018 Ngdy chip nhan dang: 11 /9/2018 NgUdi phdn bien: TS. Lam HuTu Quang
TS.UQuyThCiy
