I. Hanh trinh xu6ng:
D6 An T6tN ghiep d=140nun= 14 em
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SVTH: PHAUM DUY NGHEA
D6 An T6t N ghiep
*Sa a6 nguyen If; :
Van dien ill thay d6i vi tri nhir hinh ve. D~u qua bum, qua van d~n
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SVTH: PHAUMDUY NGHEA
5.3.2 Tinh toan cum chay dU'o'j
- Chay duoi duoc g~n c6 dinh voi b~may.
- Chi co b(>phan tham gia kep phoi chuyen dong len xuong de thuc hien
qua trinh kep va thaophoi.
Tinh luu luong vao:
Q2v = F2 .v2= 226,08 x 2,1 = 474,768 cm3/ s= 28,4911phut.
Q2ra = Fl. V2= 379,94 x2,1 = 797,874 cm3/ s= 47,87 (l/phut). ch
Pqt= 19,57N.=1,975 kg
Thay th~cac gia tri tren vao (4-3) ta duoc: ,~ =5x379,94+360+10,8+1,975 =10,08 (kg/em') 226,08 Pms!= 10,8kg Trong do: d= 140 mm F2= 226,08 cm2 Pch = 360 kg ,v2 = 21 mm/s = 2,lcm/s p; : ap lire cua buong tren :r; =5 bar.
Ta co phuong trinh can bang luc nhu sau:
F,= 379,94 cm' D=220mm P2' F ------ <, ~ r., PI - Cac thong s6 : Hinh ve D6 AnT6t N ghiep
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SVTH: PHAUM DUY NGHEA
Q3r: Luu IUQ'ngra.
Q3vLuu IUQ'ngvao.
d, :duong kinh trupiston.
P3:ap suat van ,V3:van t6c hanh trinh len V3=7mm/s
Chon Pmax = 30 t&n= 30.000 (kg). I I d ,--- r--- ,--- r--- -: -, ..._____ F ,---- - , Diu co ap suat p duoc cung cap cho buong duoi xi lanh nho van 5, ap su&t p duoc diSu chinh boi van 7 dfty4 piston cua 4 xi lanh di len de thao phoi dli ep d6ng thuc hien qua trinh kep phoi cung voi 2 xi lanh
chinh.Khi hanh trinh ep b~t diu ep xuong luu IUQ'ngduoc tran qua van 7 vS bediu dS gifr luc kep phoi,
Cac thong s6 :
D, :duong kinh piston .Chon thea may chuan D= 60 ern. Pmax hrcdfty16nnh&tcua xi lanh.
P
Sad6 nguyen ly :
1.Hanh trinh len khuon duoi:
V6i V3 = 7 mmls
Hanh trinh xuong voi chieu dai L4 = 105mm
V6i van t6CV4=V1= 10,5mm/s
D6 An T6t N ghiep
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SVTH: PHAUM DUY NGHEA
=>Q3V=Q3r= 1,05 .28,26 =29,673 cmvs = 1,78 (l/phut)
5.4.3.Cac dang tAn th~t trong h~ th6ng dAu ep:
V3=VI = 10,5mmls = 1,05crn3/s
* Tinh hru hrong:
Vi b9 ph~n kep phoi len xuong voi hanh trinh va v~n t6c nhu nhau nen hru
luong vao bang hru hrong ra. => d =K.DJ =0,65 x 60=39 rnrn Chon K =0,65 K=0,5 -;-0,8 K :h~s6 : Chon piston nang khuon: Tit cong thirc : p =30.000 =26539(bar) 3 3,14.62 ' Thay s6 vaotaduoc : P =47r.D2 p ilia! 4' 3 Vi aday dung 4xy lanh nentaco : p ,= 7r.D2.P mal 4 3 Ta co:
Vi kich thuoc cua xy lanh nho nen tabo qua rna sat va luc quan tinh cua xy lanhvapiston.
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SVTH: PHAUMDUY NGHEA
A' "
c. Ton that lipsuat:
T6n th~t ap suat la su giam ap su~t do sire b~n tren duong chuyen dong cua born diu dSn co ciu ch~p hanh. Sire can nay chu ySu do chieu dai 6ng dftn,
sirthay d6i tiStdien cua 6ng din cling nhuv~nt6c va d(>nhot cua diu gay ra. do do t6n th~t ap su~tco th~xay ra anhi~u b(>phan cua Mthong diu ep,
Po: ap su~t cua Mthong diu ep. PI :apsuat ra khoi M thong. 11c=11cb . 11cd Dodo: 77 cb Trong do: No:cong suat cua thiet bi quay born diu N: Cong su~t thuc tSdo tren true born. Tuong tu ta co ton th~tcokhi cua dong codiu. 77cb
T6n th~t co khi trong Mthong diu ep bao gom. T6n th~t co khi cua bO'm vadongco diu hay xy lanh truyen luc .T6n th~tcokhiduoc bieudi6n banghieu
su~tcokhi:
Qo: Luu hrong danh nghia cua born.
b. T6n th§t co'khi:
Trong do : Q: Luu luong thuc t~cua born khi lam viec 6'apsuat P
thtrc tinh hieu suat.
Dang t6n th~t nay la do diu chay qua cac khe ho trong co cftuep gay nen. N~u
ap su~t cang cao, Van t6c cang nho thi t6n th~t th~ tich cang Ian. T6n that th~ tich b(>phan biSn d6i nang hrong ladang k~nh~t do la : born diu, dong codiu, xy 1anhtruyen Iuc. T6n th~t th~ tich cua born diu do diu illbom rangoai va diu chay illbuong nen sang buong hut. T6n th~t cua born duoc th~ hien qua cong
Q 1'J,b= Qo
A r "
a.Ton that the tich:
15.105(K W) 960mm
+Di~u kien 6n dinh la:
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D6i voi thanh ACchiu keo nen dung tamtrong bfrtkY tnrong hop nao; Nguoi ta
cling khong cho phep hrc nem dat toihoac gftntoi giatri hrc toihan.Pj,d€tranh su mfrt 6ndinh cuathanh.
A D
Ta ki€m tra di~u kn:z·~T.rYT.7Uinthanhhcua ' '~ukien ben cuathanh AC.
E P P B C,-- ---, Trang do:
f: Bi~n dang 160nhfrt cuatha may trong mat phang ngang. lp:chi~u dai tinhtoan
I:Luc tac dungtrong mat phang nam ngang
(EJ)lg :Tris6 phu thuoc vao dang suon
Thuong ta chia than may ra lam rung doan dS xac dinh lire va goc, xoan cakh6i nguyen trencung mot don vi d<)dai.
Ta qui than may ep v~dangkhung sau
P.l!
f =48(EJ)/g
6.1Tinh toan sU'cb~n cho than may.
6.1.1 GiOi thieu v~ than may:
Than may la chi ti~tquan trong nhfrt,dung no chuandS t6hQP b<)phan cua
may tao thanh b6 tri chung cua may, N~u trong qua trinh lam viec, than may bi rung dong vase anhhuang toan b<)chinh xac cua may. Vi vay phai tinh d<)cimg
virng cua than may.
6.1.2 Phan tich h!c tac dung len than may:
Duoi tac dung cua ngoai hrcthan may bi bien danguon va xoan .Muon tinh
chinh xac ta qui d6i than may v~dang khung thea sue b~nv~t lieu. Tinh d<)cirng taiti~t dien thu gon(EJ)tg thea cong thirc:
CHU'ONGVI
TINH ToAN SUC BEN CVAMAy
Pa-~ M
77" =-p-=p:
o 0