2. Chapter 8 2
1. KHAÙINIEÄM
The slewing mechanism serve the purpose of
imparting rotary motion to metal structure of
crane integrally with the hook load.
It differs materially from the rest of crane
mechanisms consider above in that involved
in the motion are gyrating masses alone, non
of the rectilinearly displacing ones
3. Chapter 8 3
2. PHAÂN LOAÏI
a. Coät quay b. Coät coá ñònh c. Voøng töïa quay
12. Chapter 8 12
MOÂMEN CAÛN QUAY (tt):
Ma saùt oå:
Tuøy thuoäc oå coù Mv:
(oå laên, d0 : ñöôøng kính ngoõng truïc).
(oå tröôït.)
(goùt vaønh khaên : )
iiims r..AM
d
V
d
H
tr
H1 MMMM
ngang.phöôngtheolöïcphaûndocaûnMoâmen
2
d
..HM
2
d
..HM
2d
H
1tr
H
3
d
.V.M d
V
2
d
.V.M 0d
V
2
d
.V.M tbd
V
2
trng
tb
dd
d
13. Chapter 8 13
MOÂMEN CAÛN QUAY (tt) :
Loaïi coät coá ñònh
Phaûn löïc goái töïa:
dGGQV
h
bGaGLQ
H d ...
14. Chapter 8 14
MOÂMEN CAÛN QUAY (tt) :
Momen ma saùtôû oå.
(OÅ laên thöôøng)
OÅ döôùiduøngcon laên.
-> Chínhxaùc:
tr
v
tr
H
d
H MMMM 1
2
d
.H.M 1d
H
2
.. 2d
HM tr
H
2
cos.2
H
N
d
fd
NW
.2.
..2 1
2
D
).f.2d.(
2
cos.d
H
M 1
d
H
Nf
D
WM d
H ..2
2
.
quay.coät:(-)ñònhcoácoät:)(
)]1
d
D
(f2
d
D.d.
[
2
cos.2
H
M 1d
H
15. Chapter 8 15
MOÂMEN CAÛN QUAY (tt) :
b. Momen caûnquaydo ñoä
nghieâng: M2
c. Momen caûn quay do
gioù: M3
sinb.Ga.GL.QM qc2
b
a
L
Gqsin
Gcsin
Qsin
b.Fa.FL.FqM qcv3
16. Chapter 8 16
MOÂMEN CAÛN QUAY (tt) :
d. Moâmencaûn do quaùn tính
Mñ1 : cuûa chi tieát quay phaàndaãn ñoäng.
Mñ2: cuûa vaät quay quanh truïc (ôû khoûangcaùch L)
Mñ3 : cuûa caùc phaànquay.
dtm MMM
m
dc
d
t
nDG
M
.375
..
).2,11,1(
2
1
2
mm
dc
2
2d
i.t.375
n.L.Q
M
2
0m
dc
2
cc
3d
i.t.375
n).D.G(
M
c
m
n
t
.
.60
.i
M
M
cq
t
17. Chapter 8 17
MOÂMEN CAÛN QUAY (tt) :
Coâng suaátñoängcô
hoaëc
n
MM
N dt
dc .
.975
.3,1
..975
.nM
N t
dc