final and answers 2005 2006 design2 ahmedawad
DESCRIPTION
designgear design calculationsTRANSCRIPT
t.-,..:1.i*'-:'1:,;''t": AIN SHAMS UNIVERSITYFACULTY OF ENGINEERING
DESIGN & PRODUCTION ENG!NEERING DEPARTMENTTltird Year Mechanicol, power Section
Semester, 2005-2006 Time: 3 Hours
The sketch shows the outlines of a gear unit used to operate a 250mm ballvalve. The gear unit consists of two stages:
. Bevel gear drive flParameter Pinion Gear
Tooth width, mm 12 12Velocity fa;tor u., c u., cService factor 1.15 1.15Wear stiess factor lVlPa 1.4 1-4Modified form factor 0.54 - 3tzlNumber of teeth 2A 3oModule, mm 2 2
. Worm gear drive
Parameter Worm GearNo. of starts 2llead - helixl anole. deoree 10 10
J-ooth width, mmVelocitV factor o.e
250.6
Service factor 1.15 1.15Lubrication factor 1.2Wear stress factor. MPa 1.4 1.4Modified form factortturnOer otTeettl
0.54 - (3tZ)- -f- 52
Normalmodtrle. mm 3Coefficient of friction 0.2 0.2Pressure angle, deqree 20 20
You are reguired to:. lf the driving torque at the valve stem is 400 N.m1 F nd the driving torque at the operating wheel2 F nd the bevel gears r1laterials based on static strength only3 Find the worm gear material based on static strenqth orilu4 lf the valve is fully closed, what is the number or turns or ftre
qpelaling wheel to make the valve fully opened?Find the reactions at the bearing of the driving shaft.5
6 Present a Free Hand sketch for the gear unit in at ieast two views.
Exuniner: Associate ProJ/ Heshant Aly Senbel
Machine Design-lanuary-2006- ThirdletlMeclaniclal, power section [page: 2/4J
Useful Data
a
a
a
a
a
a
o
a
a
a
Gears Design Equations:
Pt:ob. b. m. K (l- b/L) K:K,.KrlK,Deformation factor : 0.1 I e / flBr+ liE*]Speed factor :2u I [1 + u]Eu: (21 x10a Mpa) F,g1: (l2xl04 Mpa)P.n : 1.2 P6
P.n:o"o.kr.b.mP*:k*.kr.b.Do/cos6P,o: Torque / radius -Prp: P, . tan g . cos 5,Pup: P, . tan o . sin 6o
tanl.:L/nd*:ip/nd*Linear pitch *o* : circular pitch *orrn *"ar
: 7f, rnq : (cos o, - p tanl, ) / (cos o + p coti)P,: Power .\ I v,Pr :Gb.b.m.K K:K,.&/K.K,Pw(womig"u.) : n . k* . b . D*n:2 cos y /ntanyP,,, : Fn . (cos o sin 1, + p cos l,)Pu* : I.o . (cos s cos 1, - psin 1,)D -T]rrw ln.ivUJ (I
a
o
o
a
a
a
a
a
a
e : Probable erTorModdle Commercial Accurate Precision
Up to 4.5 50 25 t26 60 30 l57 70 35 t70 80 40 20t2 100 50 2525 t20 60 30
e^* : Permissible (maximum)enor, [gm]
. \/-Belts Design Eguations:0: 180o + 2s: 1g0o + 2 sin-r LD-d I 2C)
Ansular contact factor (KrL
Fl
F2= gU'O
I 2 t3 4 5 6 :7 8 9 l0 t2 l5 20 25 30 35 40 50125 r00 I es 86 63 55 50 44 39 38 26 ?5 t4 l3 t2 ll IO 9
0r 180 170 160 150 t40 130 t20 ll0 r00 90 80 70Kr 1.0 0.98 0.95 0.92 0.89 0.86 0.82 0.78 0.73 0.68 0.63 0.58
Minimum Pulley diameter (d*). mm:
b 5 6 8 l0 l3 t7 20 22 25 32 40 50h 3 4 5 6 8 II 12.5 t4 t6 20 25 32d- 22 32 45 63 90 125 180 212 250 355 500 7t0
Machine Design-January-2006- Third Year Mecltarical, Power Scctiort [Page: 3/4
5 6 8 l0 13 t7 20 'r) 25 32 40 50
2 0.018 0.037 0.074 0.1 40 0.272 0515 0;136 0.810 l-t04 1.166 2.123 4.416
4 0.03 5 0.014 0.1 40 0.272 0.545 0.957 r.398 t.693 2.208 3.459 5.446 t\.6)Z
6 0.050 0.1 l0 0.206 0.405 0.810 1.398 2.061 2.502 3.238 5.152 8.096 13.25
8 0.063 0 40 0.265 0.530 .030 1.840 2.723 3.238 4.195 6.771 0.30 r6.93
t0 0.014 0 62 0.3 l6 0.640 .251 2.282 )) ll 3.901 5.078 8.1 70 2.51 20.(r I
IZ 0.08 r 0. 84 0.3 53 0.736 .472 2.650 3.827 4.490 5.888 9.421 4.72 T.ss I
l4 0.081 0 9l 0.3 83 0.810 .6t9 2.944 4.269 5.152 6.624 0.60 6.t9 26.50
16 0.081 0. 99 0.412 0.883 .766 3.165 4.637 5.520 7.213 l.56 7.66 28.70
18 0.014 0. 9l 0.412 0.883 .9t4 3.386 4.931 5.888 7.654 2.22 9.14 30.91
2A 0.059 0. 77 0.397 0.957 .987 3.533 5.078 6.035 7.8'15 2.59 9.8'1 i 1.65
22 0.037 0. 55 0.361 0.883 98',7 3.533 5.152 6.109 8.022 2.13 9.87 3 Z.)O
24 0. l0 0.309 0.8 10 .914 3.459 5.005 6.035 7.581 2.51 9.14 )-/..)o
26 0.059 0.221 0.736 1.840 J.JIZ 4.784 5.741 7.434 1.85 8.40 30.1 8
28 0.132 0.66 r.693 3.0r8 4.416 5.226 6.845 0.89 6.93 27.23
30 1.472 3.650 3.754 4.563 5.888 9.s68 4,72 23.55
Strength of some materials(Ultimate and Yield Stress, MFa)
Material ou ov
c22c35c45c60
5506006.60
750
300370400490
st 34st 37st 42
st 50
st 60
st70
340i70420500600700
190
200220250300340
30Mn537MnSi542CrMo 4
36CrNiMo434CrNiMo6'30 Cr Ni Mo 8r
600900980r0001-100
1250
-550800760900900
_10s0
Material ou o,,
cl0ct5
420s00
250300
ccazGG26GG 30
GGG 40
GTW 40
GTW 35
180220260300400400350
::-
250220200
GS 38
GS 45GS 52GS 60
380450520600
..180
220250360
15Cr3l6MnCr518CrNi8
600
8001 200
400600800
Machine Design-Jonuary-2006- Thirct Year Mechanicol, Power Section [Page: 4/4J
Sec. X-X
Note: The vatve is fully closed when the
and fully opened when Point B
Operating wheel
Bevel gears
Ball valve
Bevel gear
point A touches the worm
touches the worm
Driving shaft
Worm
Worm
Cover
Valve stem
Flow-+
Valve stem
gear sector
Cover
Worm
\ \i tI--T---\
I----r---I
,..-,*'.|- - ': atr
--a:: rilt+*
FO t.of t)ottlr Qur
oY:1o
m
0P.
Y\nn- Co56
At-tlf, d*l
tqn?= L'' ?( a*,
J-= Lx \n2
= 2trr ten2
F,=I
,B64oaxlo aL 5o So
t58 .h
(crs r< as2 -/' si'2)
(CosZo Co>lo -o'2 sinlo) ' =
67A N
ft* = (n (c's o1 ein 2 + .la au?)
F'", (Cr, Za 9r'alo + o 'Z Gs lo)
r"Eln
5Fn =
fu,,t'l /
Ft*, = 2o42 N
z4.ss 35 . zb-r k N. *.*4 I = Zo4Z x "-""1 = 5> 'Lo t FN'l^!
[ot7u.e a,L ulo(n = z-on L n -Z
-- N. v,.
in: Arivf,rg -Gv1r..e ^* op"to'ir1 -1trr."{ ? 3s.zb|xZ =
be-ve L Qe-, fl*o,;aL
{orlr.r"L 4eo': t=tzDf = Zx2-o = {o .^*
6f = \";' iA = 33.6s"
D.j = )p -t2 3io a?'69
tr..g = 5o YY\$'\
7^ 2o = zlrrf cos 7?.6?
fif o'4tS
,f.d rnlfo' =5* = 26
\z-= --- = 3.oh6 rir'n
Gs lo
= *.2 a 3, oh6
= -N.vn = ?,57
\ 2 /.-tr re
T xtonlo
x 52 = \58.4 mm
drm
zm = 3,A.ss 'ranfan lo .'J-
d.8s fi
= o.g6 E
sy*/ raib = l'5-Dg
= Zs 3o = 6o Yhm
= ?7.3h Y$q
3o4= #A =31
kJg = o.456
E'r= [i =35287 tz = t4,l
5o
3'o { '*
= SA. 11
7
N
tf" Jriv;,yr 67n' -= 3s ' zb7 n ? = 2z '5 N'"r
t; ls
6i : 325.A rr/.i"r6"^ = q77 Hf*
r
frs*, , duu= 917 x *# = a89 HPa
(l ,,,1o, - 6o, Holu;ot
3Gs lo
5Zr cosT 1o
lrJ = o.Sh -
5o5o
6b =
bu=
[-ta =
s4. 4
6to* 2sx
= a. 48h
- t. o-6 x". qghJ.v1 |
-
t.tS x l.z
= 6.5
26 z Hf*
ls 7 Hf*
Nz' . f furnes ,/, -o'n26
= 4(,u rne)
(9 fo-
N
N
N"- .f t'frnes /' *'"'ty 'lk'y' = 6'5* /'5 = ?'lS
Cos
Sfn
33 .6e
.*^3..69
?tsz
h27
285
"l *a Leadl/:
11I\A =
:
Re=
\'r91.s -- * -C
I 7rilrHFe v.
--> tt ry' d-l x - ze :
Lt
-
I1 L:1oo 6q\ _
F' (t ' 'tFt c'
,rlu
^ -- \
6 ho,5 =\vsfr 2r3'f Y o
22ll6 + 1oS
WN\ , r., =11
G\fr
It.?.
t@\z
@
,i
?._-s43 i zte