I. Loi s~tcua nam chiimdi~n; 2 LO xo; 3.Thanh SQC;
2. du ttlO va nguyen Iy ho~t dqng: a Bua rung nai cUng:
a. Bua rung nai cUng:
Lo(li bua nay co cAu410 dan gian. BI) gay rung thuiJog la cac rna I~ch tam I~p tren tf\lC quay de t~o ra l\I'c rung dl)ng. De di~u chlnh I\I'Cgay rung bfulg each di~u chinh vi tri cua rna I~ch tam. Lo~i bUa nay co nhugc diem la bl) gay rung lam anh huiJog den tu6i thQ cua dl)ng co. M~t khac neu gia tai vao ddu bUa de tang ap l\I'c len ddu CQCthl bien dl) rung giam di ro r~t.
65 5 ) ) 5 6 $ $ $ 7 8 + + + 4 c) a) 0)
Hlnh 7.5: Cac IO(libUa rung
a- Bua rung n6i c(mg; b-Bua rung n6i m~m; c- Bua va rung 1- BQ gay rung; 2- DQng co di~n; 3- B(\ truy~n da; 4- K~p dliu CQC;
5- Laxo; 6-B~ gia tai trQng; 7- Dliu bua; 8-Mii CQC.
h. Bua rung nai mSm (hinh 7.5b)
S\I khlic nhau gifra bua rung n6i c(mg va blla rung n6i mem 6 ch6 Ia lo~ n6i mem dQng ca dugc n6i vm bQ gay rung qua 16 xo. Vi th6 trong qua trinh lam vi~c dQng co khong bi anh huang do bQ gay rung gay ra, do do tu6i thQ cua dQng co dugc nang cao.
M~t khac, khi clio gia tili It:n ddu hlla thi bien d(l rung cua bua giam di khong dang c. Bua va rung (hinh 7.5c)
LO(li nay b(l ph~ gay rung dugc I~p tf\fc ti6p tren hai ddu cua tf\lC d(lng. Khi d(lng co quay C\lCI~ch tam cimg quay va tl;iora l\Ic gay rung; dang thM tl;io ra va d~p gifra hai ddu bua va truyen cho ddu CQCdS dong CQC.Co thS thay d6i l\Ic d~p bfulg cach thay dai khe h6 gifra hai ddu bUa nhiYdai 6c dieu chinh.
d. U u nhU'llc di~m va phl;lm vi sir dyng: Uu di~m:
~ Bua rung co kich thuac ddu bua nhc>gQn, tinh co d(lng cao, d~ dieu khiSn, lam vi~c tin c~y.
- Dong CQCbfulg blla rung it g~p hi~n tuqng ch6i gia, CQCkhong bi va nhu khi dimg bua va d~p.
- Co thS dimg bua rung dS nh6 CQC.
- Khi dong CQCco thS khong dimg gia dfut huang ddu bUa. Nhtrqc di~m:
- L\Ic rung d(lng lam giam tu6i thQ Clla d(lng co va gay anh huang x~u den cac cong trinh Ian c~. DS giam l\Ic rung d(lng truyen ra cac cong trinh Ian c~, co thS dao duiYng hao dS ngan cach:
- Thay vi dimg gia dfut huang thi bua rung phili dung cdn trvc t\f hanh dS nang hl;lbua khi dong CQC;phili su d\lllg cac thiet bi phat l\Ic nhu may phlit di~n, may born thuy I\IC. May phlit di~n cung dp nang luqng di~n cho ddu bUa hO(lt d(lng, may born thuy l\Ic cung c~p ddu thuy l\Ic co ap su~t cao cho b(l ph~ xilanh k~p CQCduai ddu bua.
(7.1)
(7.2) Bua rung thuang dUng d~ dong CQCco ti~t di~n nho vao n~n dAtit co dQ deo dinh. Cac 10\UCQCthuang dUQc dong bfulg bUa rung nhu: CQCvan thep, CQC5ng thep, CQC thep hinh, CQCbetong c6t thep ti~t di~n nho (lOOxlOO d~n 300x300). .
Bua rung nh6 CQCrAt hi~u qua nen dUQCdUng d~ dong va nh6 5ng vach khi thi cong CQCkhoan nh6i; dong va nh6 dui dful bAc thAm hay 6ng dful cat d~ xu Iy n~n dilt y~u. 7.2.5. Tinh nang suat clla bua dong CQC
*Cong suit cua bUa diezen
p= A.n/(lOOO. 60) (KW) Trongdo: .
A- nling Iuqng rai CllabUa (N.m)
n- s6 Ian roi cua bUa trong mQt philt (lfuvphut) *Cong suat bua rung
P =p.y.n/(lOOO. 60) (KW) Trong do: p- l\fc ray rung (N)