Implementing Precast, Prestressed Concrete Bridge Girder ...
bridge girder auncher Calculation Sheet Part 2
Transcript of bridge girder auncher Calculation Sheet Part 2
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Mid Support ......................................................................................... 1
4.1MID SUPPORT CONSIST OF SOME PARTS AS FOLLOWS .......................... 1
4.2FORCE ANALYSIS ..................................................................................................................... 1
Calculation of launching roller .................................................. 7
5.1SECTIONAL CHARACTER OF BEAM IS AS THE FOLLOWING DIAGRAM ............................. 7
5.2CALCULATION OF SUPPORT ....................................................................................................... 9
5.3PIN SHAFT OF INSIDE AND OUTSIDE BUSHING .......................................................................... 10
5.4PRESSURE STRESS OF INSIDE BUSHING HOLE'S WALL .............................................................. 10
Calculation of rear support ......................................................... 11
6.1SECTIONAL CHARACTER OF OUTSIDE BUSHING JOINT BEAM IS AS THE FOLLOWING
DIAGRAM ................................................................................................................................................... 11
6.2CALCULATION OF SUPPORT ...................................................................................................... 12
6.3PIN SHAFT OF INSIDE AND OUTSIDE BUSHING .......................................................................... 13
6.4PRESSURE STRESS OF INSIDE BUSHING HOLE'S WALL ............................................................. 14
Calculation of machine and transmission parts ........... 15
7.1CALCULATION FOR FRONT SUPPORT'S DRIVING AND TRANSMITTING PARTS ............ 15
7.2 CALCULATION FOR REAR SUPPORT'S DRIVING AND TRANSMITTING PARTS ............. 25
7.3CALCULATION FOR HANG TRANSMITTING PARTS ................................................... 35
7.4CALCULATION FOR HANG WHEEL .......................................................................................... 46
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Mid Support
4.1
Mid support consist of some
parts as follows
1 Top trimmer 2 Hang and launching roller
equipment 3 Upright 4 Lower trimmer 5 Running
wheel box 9 Transverse orbit
4.2
Force analysis
F=110
Q345B
Mid support is the worst working condition when beam launcher is erecting
boundary beam: the stress of every upright is F=110t, make force analysis in this
working condition. material of main structure is Q345B.
4.2.1 Calculation of top trimmer
4.2.1.1 The structural form of top trimmer is as follows
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4.2.1.2 Sectional character of top trimmer is as follows
M max=110X1.317/4=36.2tm
The maximum bending moment is M max=110X1.317/4=36.2tm.
Q=55t
The shearing force on the span is Q=55t.
max=36.2/0.3=120MPa
The maximum bending stress is max=36.2/0.3=120MPa.
max=55/8832=62MPa
The average bending shearing force is max=55/8832=62MPa.
=161MPa
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4.2.2 Calculation of upright
Nmax=110t
The maximum axial force is N max=110t.
max=110/24768=44MPa
The maximum pressure stress is max=110/24768=44MPa.
4.2.3 Calculation of lower trimmer
4.2.3.1 Structural form of lower trimmer is as follows
4.2.3.2 Sectional character
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Sectional character of lower trimmer's cross-girder
Sectional character of lower trimmer's cantilever-girder
4.2.3.3 Calculation
1) Calculation of cross-girder
M max=110X0.77=84.7tm
The maximum bending moment is M max=110X0.77=84.7tm.
Q=110t
The maximum shearing force is Q=110t.
max=84.7/0.51=184MPa
The maximum bending stress is max=84.7/0.51=184MPa.
max=110/10032/3=36MPa
The average shearing stress is max=110/10032/3=36MPa
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400mm
There're one fulcrum every 400mm length of transverse orbit.
M max=110/2X0.4/4=5.5tm
The maximum bending moment is M max=110/2X0.4/4=5.5tm.
Q=55t
The maximum shearing stress is Q=55t.
max=5.5/0.12=46MPa
The maximum bending stress is max=5.5/0.12=46MPa.
max=55/2/6136=53MPa
The average shearing stress is max=55/2/6136=53MPa.
=103MPa
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Calculation of launching roller
5.1
Sectional character of beam is as the
following diagram
Force diagram
Bending moment diagram
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Shearing stress diagram
The maximum bending moment
mttFL
M === 15.304m34.190
4
max
Shearing stress
tQ 45max
=
Normal stress
a4.18067.1670826
301500000MP
W
M
X
===
Shearing stress
MPaSQ
35.81167082667162
9664001045
I2
4
max=
==
Translational stress
[ ] MPaMPa 2409.22835.8134.1803 2222 =
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5.2
Calculation of support
Axial force
N=90t
Length
L=3064mm
Slenderness ratio
84.3616.83
3064==
i
L
Stability coefficient of pressure force
946.0=
[ ] MPaMPA
N180a9.128
7382.7946.0
109 5
=
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5.3
Pin shaft of inside and outside bushing
45t
The shearing force is 45t, and double shearing.
Shearing stress
MPaMPaA
Q560][5.58
5.38482
1045
2
4
=
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Calculation of rear support
6.1
Sectional character of outside
bushing joint beam is as the following diagram
The maximum bending moment
mttFL
M === 4.134m34.1404
max
Shearing stress
tQ 20max =
Normal stress
a2.921452815
134000000MP
W
M
X
===
Shearing stress
MPaSQ
2.33
185027078122
7370001020
I2
4
max=
==
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Stability coefficient of pressure force
839.0=
[ ] MPaMPAN
180a6.647382.7839.0
104 5
=
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6.4
Pressure stress of inside bushing hole's wall
40t
The shearing force is 40t, and double shearing.
[ ] MPaMPd
Q180a9.129
0722
1020 4
=
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Calculation of machine and
transmission parts
7.1
Calculation for front support's driving
and transmitting parts
Working grade: M4
The maximum static wheel-pressure: 56t
The maximum dynamic wheel-pressure: 50t
The minimum dynamic wheel-pressure: 12t
Running speed: 1.67m/min
Gradient: 0.5%
Wind speed at working condition: 15.5m/s
7.1.1 Original design parameter
Driving form: 1/2 driving
Diameter of wheel tread: 500mm
Width of orbit: 110mm
Diameter of wheel shaft: 140mm
=0.004
The frication resistance coefficient of self-aligning roller bearing is=0.004.
n=1.063r/min
The revolving speed of wheel is n=1.063r/min according to above.
7.1.2 Strength checking of wheel
7.1.2.1 Equivalent working wheel-pressure
P mean=2Pmax+Pmin/3=2X50+12/3=37.3 t
GB/T3811 According to GB/T3811
Allowable unit pressure of wheel's material: K=5.6
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Revolving speed coefficient of wheel: C1=1.17
Working grade coefficient: C2=1.12
Allowable wheel-pressure of that wheel
P=KDlC1C2=5.6X500X110X1.17X1.12=403603N40.3t
PP mean
7.1.2.2 Static strength checking
P max=1.9KDl=1.9X5.6X500X110=585200 N58.5.t
P max
P max is greater than the maximum wheel-pressure of static load.
Hereby the select wheel is suitable.
7.1.3 Calculation of running resistance
7.1.3.1 Friction resistance
Pm = P(d+ 2fk)CfD
GB3811 According to GB3811
Rolling friction force-arm of wheel
fk= 0.5
Additional friction resistance coefficient
Cf= 1.5
Pm=50e4X2X0.004X120+2X0.5X1.5/500=2160 N
7.1.3.2
Gradient resistance
P = mg tan = 50ex 2 0.005 = 2500N
7.1.3.3Wind resistance
PW1=0.6CPA
Wind area: A=120 m2
Wind coefficient : C=1.35
P=0.625V2=0.625X15.5
2=150
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PW1=0.6X1.35X150X120=14595 N
Running resistance
Pj=2160+2500+14595=19255 N
7.1.4 Calculation for motor's power
P = KPjV (1000)
In this formula
K=1.2; =0.8
And therefore
P=1.2X19255X1.67/60X1000X0.8=0.804KW
P=1.1KW
The motor's power is P=1.1KW
7.1.5 Transmission ratio allocation and
reducer type
Revolving speed of wheel: n=1.063r/min
Output revolving speed of motor: nz=1430 r/min
The total transmitted ratio: i=1430/1.063=1345
Primary reducer type: KF97R67-516.2-1.1/4
The transmitted ratio: i=516.2
The transmitted ratio of the open gear:
i=1345/516.2=2.6056
The tooth number of small gear: Z1=18
The tooth number of large gear: Z2=47
The actual transmitted ratio:
iactual = 516.2 47 18 = 1347.856
Theoretical running speed of wheel
v = DN 1000 = 500 1430 1347.856 1000 = 1.666 m min
The rate of speed difference
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P=1.67-1.666/1.67=0.002
The distribution of transmitted ratio is suitable.
7.1.6 Calculation for output torque of reducer
Output torque of motor:
T=9550P/N=7.346 Nm
Translational pull force of wheel
F=2000XTXI/D=2X7.346X1347.856/500=39606 N
FPj
Meet requirement.
7.1.7 Calculation for slipping of wheel
Viscous force of every wheel
Fd = 50ex 0.1 = 50000N
Viscous force is greater than total static resistance.
Meet requirement.
The reducer is suitable according to above.
7.1.8 Calculate shaft's strength according to
composited bending moment and torque
7.1.8.1 Calculation for strength of shaft
Allowable stress of shaft
p=320MPa; -1p=90MPa
Fulcrum distance: L=370 mm
Bending moment of shaft
M=Pl/4=56e4X370/4000=51800 Nm
Torque of shaft
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T=FD/2=19255X500/2000=4813 Nm
Correction coefficient: =0.3
The diameter of mandrel: d=123.7 mm
Tentative diameter is d=140mm in consideration of
shaft's stiffness requirement.
7.1.8.2 Calculation for deflection of shaft
Inertia moment of shaft: I=18857410
Elasticity modulus: E=290000
Deflection: yp = FL3 (48EI) = 0.096mm
Allowable maximum deflection of shaft
ypmax = 0.0005XL = 0.185mm
The actual deflection is lesser than allowable maximum deflection.
Therefore, sectional diameter of shaft is suitable.
7.1.9 Calculation for bearing
7.1.9.1 Elementary rated dynamic load
Bearing quantity of every wheel: m=2
Load of every wheel: p=50t
Diameter of shaft: d=140 mm
Radial load: Fr=280 KN
Radial equivalent dynamic load: Pr=250KN
Radial equivalent static load: Pr=280KN
Elementary rated dynamic load of bearing
C = fhfmfdP = (fnft)
Service life of bearing: Lh = 1000h
Life coefficient: fh
= 1
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Speed coefficient: fn = 1.435
Moment load factor: fm = 2
Impulse load factor: fd = 1.2
Temperature factor: ft= 1.435
Elementary rated offered load: C=418.1 KN
Designate bearing type: 23228CC
And elementary rated dynamic load: Cr=812 KN
7.1.9.2 Rated static load of bearing
Safety factor: S0= 3
And: C0= 3 280 = 840KN
Sectional elementary static load of bearing
C0r=1300 KN
Therefore the sectional bearing is suitable.
7.1.10 Strength checking for spline
Diameter of shaft: D=340mm
Width of spline: b=28 mm
Height of spline: h=16mm
Length of spline: l=60mm
Tangent height between spline and wheel hub
k=0.4X16=6.4mm
Transmitted torque by spline: T=3792Nm
A Choose the A type double spline
P = 2T (1.5DKI) = 2 3792 [1.53406.4 (60 28)] = 72.6MPa
Therefore the sectional spline is suitable.
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7.1.11 Strength calculation of gear
7.1.11.1 Elementary parameter
Full load working hour: T=5000h
Transmitted power by gear: P=1.1KW
Revolving speed of pinion: n1=2.77r/min
Tooth number of pinion: z1=18
Tooth number of gear wheel: z2=47
Primary module of gear: m=10
Center distance of gear: a=325mm
Primary facewidth: b=60mm
7.1.11.2 Allowable stress of material
Hlim1=950MPa; Hlim2=920MPa
Flim1=350MPa; Flim2=340MPa
Allowable contact stress
Hp=0.9Hlim; Hp =828MPa
7.1.11.3 Contact stress checking of tooth flank
1 Reference nominal tangential force: FT=42134
2 Service factor: KA
P14-136 14-1-71 Review table 14-1-71 of page P14-136
KA=1.25
3 Dynamic load factor: KV
Linear velocity of pinion: v=0.0261 m/s
Transmission accuracy coefficient
C=-0.5048lnZ-1.144lnm+2.825lnfpt+3.32
fpt=25m C=8.32 C=8
There into, fpt=25m, and C=8.32, use C=8
P14-140 14-1-74KV=1
Review diagram 14-1-74 of page P14-140, KV=1
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4 Spread factor of helix line load: Kh
P14-145 14-1-88 Review table 14-1-88 of page P14-145
Kh=a1+a2[1+a3(b/d1)2](b/d1)
2+a4b
There into: a1=1.15a2=0.18a3=6.7a4=0.00031
Therefore: Kh=1.203
5 Spread factor of inter-tooth load: KH
KAFt/b=877.7974
P14-146 14-1-92 Review table 14-1-92 of page P14-146: KH=1.2
6 Pitch point area factor: ZH
P14-149 14-1-76 Review diagram of page P14-149: ZH=1.5
7 Elastic coefficient: ZE
P14-150 14-1-95 Review table 14-1-95 of page P14-150: ZE=189.8
8 Contact ratio coefficient: Z
Spur gear is without shift
=0, =1, and Z=1
9 Helical angle factor: Z
Spur gear: =0, and Z=1
10Meshing factor of pinion and gear: ZB ZD
14-1-94 According to the judging criteria of table 14-1-94
There into: =20
da1=200 mm, db1=73.45477 mm
da2=490 mm, db2=191.7986 mm
M1=0.98744, M2=0.944101
So: ZB=1 ZD=1
11 Calculate contact stress: H
H1=888.5211MPa, H2=888.5211MPa
12 Life factor: ZNT
Stress cycle-index
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NL1=831073.2, NL2=318283.4
According to table 14-1-96
ZNT1=1.561975, ZNT2=1.676624
13 Impact factor of lubricating oil: ZLZVZR
14-1-98 Get gear pair by generating method
according to table 14-1-98
RZ104m, ZLZVZR=0.85
14Working harden factor of tooth surface: ZW
HRC50-55 470HB
Hard tooth surface HRC50-55 is greater than 470HB.
Therefore: ZW=1
15 Size factor: ZX
According to table 14-1-99: ZX=1
16 Safety factor method
SH =HlimZNT ZLZVZRZW ZX H
Therefore: SH1=1.419544
SH1=1.47562
According to table 14-1-100: SHmin = 1.1
Meet requirement.
7.1.11.4 Bending stress checking of gear
1 Spread factor of helical load: KF=KHN
N=b/h2/[1+b/h+(b/h)2]
There into b=60, H=2.25m=22.5
So: N=0.659794, KF=1.129992
2 Partition coefficient of helical load: KF
KF=KH=1.2
3 Tooth profile coefficient: YF
Equivalent tooth number: zn1=18, zn2=47
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According to diagram 14-1-98
YF1=2.9, YF2=2.35
4 Stress correction factor: YS
According to diagram 14-1-103
YS1=1.54, YS2=1.68
5 Contact ratio coefficient: Y
Because: =1 =0
So: Y=1
6 Helical angle coefficient : Y
According to diagram 14-1-109
Y=1
7 Calculation of root stress: F
F= FTYFa YSa Y Y KAKVKF KF
F1=531.581MPa, F2=469.924MPa
8 Stress correction factor of test gear: YST
According to table 14-1-101
YST=2
9 Life factor
YNT =(3000000 NL)0.02, YNT 1= 1.026005, YNT 2= 1.04589
10 Relatively root sensitivity coefficient
According to table 14-1-102 and diagram 14-1-98
YrelT = 1
11 Relatively root surface condition factor
According diagram 14-1-118
RRrelT = 1
12 Size factor: YX
14-1-109 According to the formula of table 14-1-109
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YX=1.03-0.006m, YX=0.97
13 Safety factor of bending strength: SF
SF=Flim YST YNT Yrel YRrel YX
SF1=1.31, SF2=1.468
According to table 14-1-100: SFmin = 1.25
It's suitable.
7.2 Calculation for rear support's driving
and transmitting parts
Working grade: M4
The maximum static wheel-pressure: 32t
The maximum dynamic wheel-pressure: 30t
The minimum dynamic wheel-pressure: 12t
Running speed: 1.67m/min
Gradient: 0.5%
Wind speed at working condition: 15.5m/s
7.2.1 Original design parameter
Driving form: 1/2 driving
Diameter of wheel tread: 500mm
Width of orbit: 80mm
Diameter of wheel shaft: 120mm
=0.004
The frication resistance coefficient of self-aligning roller bearing is=0.004.
n=1.063r/min
The revolving speed of wheel is n=1.063r/min according above.
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7.2.2 Strength checking of wheel
7.2.2.1 Equivalent working wheel-pressure
P mean=2Pmax+Pmin/3=2X30+12/3=24 t
GB/T3811 According to GB/T3811
Allowable unit pressure of wheel's material: K=5.6
Revolving speed factor of coefficient: C1=1.17
Working grade coefficient: C2=1.12
Allowable wheel-pressure of the select wheel
P=KDlC1C2=5.6X500X80X1.17X1.12=293529 N29.3t
PP mean
7.2.2.2 Static strength checking
P max=1.9KDl=1.9X5.6X500X80=425600 N42.t
P max
P max is greater than the maximum wheel-pressure of static load.
Hereby the select wheel is suitable.
7.2.3 Calculation of running resistance
7.2.3.1 Friction resistance
Pm = P(d+ 2fk)CfD
GB3811 According to GB3811
Rolling friction force -arm of wheel
fk= 0.5
Additional friction resistance coefficient
Cf= 1.5
Pm = 30e4 4 2 (0.004 120 + 2 0.5) 1.5 500 = 2376N
7.2.3.2 Gradient resistance
P = mg tan a = 30e4
2 0.005 = 3000N
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7.2.3.3Wind resistance
PW1=0.6CPA
Wind area: A=120 m2
Wind coefficient: C=1.35
P=0.625V2=0.625X15.5
2=150
PW1=0.6X1.35X150X120=14595 N
Running resistance
Pj=2376+3000+14595=19971 N
7.2.4 Calculation for motor's power
P = KPjV (1000)
In this formula
K=1.2, =0.8
And so
P=1.2X19971X1.67/1000X0.8=0.834KW
P=1.1KW
The motor's power is P=1.1KW
7.2.5 Transmitted ratio allocation and reducer
type
Revolving speed of wheel: n=1.063r/min
Output revolving speed of motor: nz=1430 r/min
The total transmitted ratio: i=1430/1.063=1345
Primary reducer type: KF97R67-516.2-1.1/4
The transmitted ratio: i=516.2
The transmitted ratio of the open gear:
i=1345/516.2=2.6056
The tooth number of opinion: Z1=18
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The tooth number of wheel gear: Z2=47
The actual transmitted ratio:
iactual = 516.2 47 18 = 1347.856
Theoretical running speed of wheel
v = DN 1000 = 500 1430 1347.856 1000 = 1.666 m min
The rate of speed difference
P=1.67-1.666/1.67=0.002
The distribution of transmitted ratio is suitable.
7.2.6
Output torque of motor
T=9550P/N=7.346 Nm
Translational pull force of wheel
F=2000XTXI/D=2X7.346X1347.856/500=39606 N
F > Pj
Meet requirement
7.2.7 Calculation for slipping of wheel
Viscous force of every wheel
Fd = 30e4 0.1 = 30000N
Viscous force is greater than total static resistance.
Meet requirement.
The reducer is suitable according to above.
7.2.8 Calculate shaft's strength according to
composited bending moment and torque
7.2.8.1 Calculation for strength of shaft
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Allowable stress of shaft
p=320MPa, -1p=90MPa
Fulcrum distance: L=344 mm
Bending moment of shaft
M=Pl/4=32e4X344/4000=25800 Nm
Torque of shaft
T=FD/2=19971X500/2000=2992 Nm
Correction coefficient: =0.3
The diameter of mandrel: d=103.6 mm
Tentative diameter is d=140mm in consideration of
shaft's stiffness requirement.
7.2.8.2 Calculation for deflection of shaft
Inertia moment of shaft: I=10178760
Elasticity modulus: E=290000
Deflection: yp = FL3 (48EI) = 0.086mm
Allowable maximum deflection of shaft
ypmax = 0.0005XL = 0.172mm
The actual deflection is lesser than allowable maximum deflection.
Therefore, sectional diameter of shaft is suitable.
7.2.9 Calculation for bearing
7.2.9.1 Elementary rated dynamic load
Bearing quantity of every wheel: m=2
Load of every wheel: p=32t
Diameter of shaft: d=120 mm
Radial load: Fr=160 KN
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Radial equivalent dynamic load: Pr=150KN
Radial equivalent static load: Pr=160KN
Elementary rated dynamic load of bearing
C = fhfmfdP = (fnft)
Service life of bearing: Lh = 1000h
Life coefficient: fh = 1
Speed coefficient: fn=1.435
Moment load factor: fm = 2
Impulse load factor: fd = 1.2
Temperature factor: ft= 1.435
Elementary rated offered load: C= 267.6KN
Designate bearing type: 23124CC
And elementary rated dynamic load: Cr=450 KN
7.2.9.2 Rated static load of bearing
Safety factor: S0= 3
And: C0= 3 160 = 480KN
Sectional elementary static load of bearing
C0r=722 KN
Therefore the sectional bearing is suitable.
7.2.10 Strength checking for spline
Diameter of shaft: D=340mm
Width of spline: b=28 mm
Height of spline: h=16mm
Length of spline: l=60mm
Tangent height between spline and wheel hub
k=0.4X16=6.4mm
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Transmitted torque by spline: T=3792Nm
A Choose the A type double spline
P = 2T (1.5DKI) = 2 3792 [1.53406.4 (60 28)] = 72.6MPa
Therefore the sectional spline is suitable.
7.2.11 Strength calculation of gear
7.2.11.1 Elementary parameter
Full load working hour: T=5000h
Transmitted power by gear: P=1.1KW
Revolving speed of pinion: n1=2.77r/min
Tooth number of pinion: z1=18
Tooth number of gear wheel: z2=47
Primary module of gear: m=10
Center distance of gear: a=325mm
Primary facewidth: b=60mm
7.2.11.2 Allowable stress of material
Hlim1=950MPa; Hlim2=920MPa
Flim1=350MPa; Flim2=340MPa
Allowable contact stress
Hp = 0.9Hlim ; Hp = 828MPa
7.2.11.3
Contact stress checking of tooth flank
1 Reference nominal tangential force: FT=42134
2 Service factor: KA
P14-136 14-1-71 Review table 14-1-71 of page P14-136
KA=1.25
3 Dynamic load factor: KV
Linear velocity of pinion: v=0.0261 m/s
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Transmission accuracy coefficient
C=-0.5048lnZ-1.144lnm+2.825lnfpt+3.32
fpt=25m C=8.32 C=8
There into, fpt=25m, and C=8.32, use C=8
P14-140 14-1-74KV=1
Review diagram 14-1-74 of page P14-140, KV=1
4 Spread factor of helix line load: Kh
P14-145 14-1-88 Review table 14-1-88 of page P14-145
Kh=a1+a2[1+a3(b/d1)2](b/d1)
2+a4b
There into: a1=1.15a2=0.18a3=6.7a4=0.00031
Therefore: Kh=1.203
5 Spread factor of inter-tooth load: KH
KAFt/b=877.7974
P14-146 14-1-92 Review table 14-1-92 of page P14-146: KH=1.2
6 Pitch point area factor: ZH
P14-149 14-1-76 Review diagram of page P14-149: ZH=1.5
7 Elastic coefficient: ZE
P14-150 14-1-95 Review table 14-1-95 of page P14-150: ZE=189.8
8 Contact ratio coefficient: Z
Spur gear is without shift
=0, =1, and Z=1
9 Helical angle factor: Z
Spur gear: =0, and Z=1
10Meshing factor of pinion and gear: ZB ZD
14-1-94 According to the judging criteria of table 14-1-94
There into: =20
da1=200 mm, db1=73.45477 mm
da2=490 mm, db2=191.7986 mm
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M1=0.98744, M2=0.944101
So: ZB=1 ZD=1
11 Calculate contact stress: H
H1=888.5211MPa, H2=888.5211MPa
12 Life factor: ZNT
Stress cycle-index
NL1=831073.2, NL2=318283.4
According to table 14-1-96
ZNT1=1.561975, ZNT2=1.676624
13 Impact factor of lubricating oil: ZLZVZR
14-1-98 Get gear pair by generating method
according to table 14-1-98
RZ104m, ZLZVZR=0.85
14Working harden factor of tooth surface: ZW
HRC50-55 470HB
Hard tooth surface HRC50-55 is greater than 470HB.
Therefore: ZW=1
15 Size factor: ZX
According to table 14-1-99: ZX=1
16 Safety factor method
SH =HlimZNT ZLZVZRZW ZX H
Therefore: SH1=1.419544
SH1=1.47562
According to table 14-1-100: SHmin = 1.1
Meet requirement.
7.2.11.4 Bending stress checking of gear
1 Spread factor of helical load: KF=KHN
N=b/h2/[1+b/h+(b/h)2]
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There into b=60, H=2.25m=22.5
So: N=0.659794, KF=1.129992
2 Partition coefficient of helical load: KF
KF=KH=1.2
3 Tooth profile coefficient: YF
Equivalent tooth number: zn1=18, zn2=47
According to diagram 14-1-98
YF1=2.9, YF2=2.35
4 Stress correction factor: YS
According to diagram 14-1-103
YS1=1.54, YS2=1.68
5 Contact ratio coefficient: Y
Because: =1 =0
So: Y=1
6 Helical angle coefficient : Y
According to diagram 14-1-109
Y=1
7 Calculation of root stress: F
F= FTYFa YSa Y Y KAKVKF KF
F1=531.581MPa, F2=469.924MPa
8 Stress correction factor of test gear: YST
According to table 14-1-101
YST=2
9 Life factor
YNT =(3000000 NL)0.02, YNT 1= 1.026005, YNT 2= 1.04589
10 Relatively root sensitivity coefficient
According to table 14-1-102 and diagram 14-1-98
YrelT = 1
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11 Relatively root surface condition factor
According diagram 14-1-118
RRrelT = 1
12 Size factor: YX
14-1-109 According to the formula of table 14-1-109
YX=1.03-0.006m, YX=0.97
13 Safety factor of bending strength: SF
SF=Flim YST YNT Yrel YRrel YX
SF1=1.31, SF2=1.468
According to table 14-1-100: SFmin = 1.25
It's suitable.
7.3 Calculation for hang transmitting parts
Working grade: M4
The maximum static wheel-pressure: 32t
The maximum dynamic wheel-pressure: 30t
The minimum dynamic wheel: 10t
Running speed: 4m/min
Gradient: 1%
Wind speed at working condition: 15.5m/s
7.3.1 Elementary designed parameter
Driving form: 1/4 driving and coupling
Diameter of wheel tread: 260mm
Width of orbit: 140mm
Diameter of wheel shaft: 110mm
=0.004
The friction resistance of self-aligning roller bearing is=0.004.
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n=4.897r/min
The revolving speed of wheel is n=4.897r/min according above.
7.3.2
Strength checking of wheel
7.3.2.1 Equivalent working wheel-pressure
Pmean =2Pmax + Pmin
3 =
2 30 + 10
3 = 23.3t
GB/T3811 According to GB/T3811
Allowable unit pressure of wheel's material: K=5.6
Revolving speed coefficient of wheel: C1=1.17
Working grade coefficient: C2=1.12
Allowable wheel-pressure of select wheel
P = KDIC1C2= 5.6 260 140 1.17 1.12 = 2671112N 26.7t
P > Pmean
7.3.2.2 Static strength checking
Pmax = 1.9KDI = 1.9 5.6 260 140 = 387296N 38.7t
max
P max is greater than the maximum wheel-pressure static load.
Hereby the select wheel is suitable.
7.3.3 Calculation of running resistance
7.3.3.1 Friction resistance
Pm = P(d+ 2fk)CfD
GB3811 According to GB3811
Rolling friction force-arm of wheel
fk= 0.5
Additional friction resistance coefficient
Cf= 1.5
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Pm=30e4 4 (0.004 110 + 2 0.5) 1.5 260 = 10800N
7.3.3.2 Gradient resistance
P = mg tan a = 30e4 4 0.01 = 12000N
7.3.3.3Wind resistance
PW1=0.6CPA
Wind area: A=18 m2
Wind coefficient: C=1.35
P=0.625V2=0.625X15.5
2=150
PW1=0.6X1.35X150X180=2189 N
Running resistance
Pj= 10800 + 12000 + 2189 = 24989N
7.3.4 Calculation for motor's power
P = KPjV (1000)
In this formula
K=1.2, =0.8
And so
P=1.2X24989X4/1000X0.8=2.498KW
P=3KW
The motor's power is P=3KW
7.3.5 Transmitted ratio allocation and reducer
type
Revolving speed of wheel: n=4.897r/min
Output revolving speed of motor: nz=1430 r/min
The total transmitted ratio: i=1430/4.897=289.969
Primary reducer type: KF87-103-3kw/4
The transmitted ratio: i=103
The transmitted ratio of the open gear:
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i=289.969/103=2.815233
The tooth number of opinion: Z1=19
The tooth number of wheel gear: Z2=53
The actual transmitted ratio:
iactual = 103 53 19 = 287.3158
Theoretical running speed of wheel
v = DN 1000 = 260 1430 287.3158 1000 = 4.03 m min
The rate of speed difference
P=4.03-4/4=0.0075
The distribution of transmitted ratio is suitable.
7.3.6 Output torque checking of reducer
Output torque of motor
T=9550P/N=20.176 Nm
Translational pull force of wheel
F=2000XTXI/D=2X7.346X1347.856/260=44591 N
FPj
Meet requirement
7.3.7 Calculation for slipping of wheel
Viscous force of every wheel
Fd = 2 30e4 0.1 = 60000N
Viscous force is greater than total static resistance.
Meet requirement.
The reducer is suitable according to above.
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7.3.8 Calculate shaft's strength according to
composited bending moment and torque
7.3.8.1 Calculation for strength of shaft
Allowable stress of shaft
p=320MPa, -1p=90MPa
Fulcrum distance: L=390 mm
Bending moment of shaft
M=Pl/4=32e4X390/4000=29250Nm
Torque of shaft
T=FD/2=24989X260/2000=3248.6 Nm
Correction coefficient: =0.3
The diameter of mandrel: d=97.6 mm
Tentative diameter is d=110mm in consideration of
shaft's stiffness requirement.
7.3.8.2 Calculation for deflection of shaft
Inertia moment of shaft: I=7186884
Elasticity modulus: E=290000
Deflection: yp = FL3 (48EI) = 0.177mm
Allowable maximum deflection of shaft
ypmax = 0.0005XL = 0.195mm
The actual deflection is lesser than allowable maximum deflection.
Therefore, sectional diameter of shaft is suitable.
7.3.9 Calculation for bearing
7.3.9.1 Elementary rated dynamic load
Bearing quantity of every wheel: m=2
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Load of every wheel: p=32t
Diameter of shaft: d=110 mm
Radial load: Fr=160 KN
Radial equivalent dynamic load: Pr=150KN
Radial equivalent static load: Pr=160KN
Elementary rated dynamic load of bearing
C = fhfmfdP = (fnft)
Service life of bearing: Lh= 1000h
Life coefficient: fh = 1
Speed coefficient: fn=1.435
Moment load factor: fm = 2
Impulse load factor: fd = 1.2
Temperature factor: ft= 1
Elementary rated offered load: C=267.6 KN
Designate bearing type: 23122CC
And elementary rated dynamic load: Cr=378 KN
7.3.9.2 Rated static load of bearing
Safety factor: S0=3
And: C0= 3 160 = 480KN
Sectional elementary static load of bearing
C0r=602KN
Therefore the sectional bearing is suitable.
7.3.10 Strength checking for spline
Diameter of shaft: D=110mm
Width of spline: b=28 mm
Height of spline: h=16mm
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Length of spline: l=160mm
Tangent height between spline and wheel hub
k=0.4X16=6.4mm
Transmitted torque by spline: T=2078Nm
A Choose the A type double spline
P = 2T (1.5DKI) = 2 2078 [1.5 110 6.4 (160 28)] = 44.7MPa
Therefore the sectional spline is suitable.
7.3.11
Strength calculation of gear
7.3.11.1 Elementary parameter
Full load working hour: T=5000h
Transmitted power by gear: P=3KW
Revolving speed of pinion: n1=13.786r/min
Tooth number of pinion: z1=19
Tooth number of gear wheel: z2=53
Primary module of gear: m=8
Center distance of gear: a=288mm
Primary facewidth: b=50mm
7.3.11.2 Allowable stress of material
Hlim1=950MPa; Hlim2=920MPa
Flim1=350MPa;
Flim2=340MPa
Allowable contact stress
Hp=0.9Hlim; Hp =828MPa
7.3.11.3 Contact stress checking of tooth flank
1 Reference nominal tangential force: FT=42134 N
2 Service factor: KA
P14-136 14-1-71 Review table 14-1-71 of page P14-136
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KA=1.25
3 Dynamic load factor: KV
Linear velocity of pinion: v=0.1097 m/s
Transmission accuracy coefficient
C=-0.5048lnZ-1.144lnm+2.825lnfpt+3.32
fpt=25 m C=8.548 C=8
There into, fpt=25m, and C=8548, use C=8
P14-140 14-1-74KV=1
Review diagram 14-1-74 of page P14-140, KV=1
4 Spread factor of helix line load: Kh
P14-145 14-1-88 Review table 14-1-88 of page P14-145
Kh=a1+a2[1+a3(b/d1)2](b/d1)
2+a4b
There into: a1=1.15a2=0.18a3=6.7a4=0.00031
Therefore: Kh=1.1991
5 Spread factor of inter-tooth load: KH
KAFt/b=683.5966
P14-146 14-1-92 Review table 14-1-92 of page P14-146: KH=1.2
6 Pitch point area factor: ZH
P14-149 14-1-76 Review diagram of page P14-149: ZH=1.5
7 Elastic coefficient: ZE
P14-150 14-1-95 Review table 14-1-95 of page P14-150: ZE=189.8
8 Contact ratio coefficient: Z
Spur gear is without shift
=0, =1, and Z=1
9 Helical angle factor: Z
Spur gear: =0, and Z=1
10Meshing factor of pinion and gear: ZB ZD
14-1-94 According to the judging criteria of table 14-1-94
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There into: =20
da1=168 mm, db1=62.028 mm
da2=440 mm, db2=173.027 mm
M1=0.989476, M2=0.946497
So: ZB=1 ZD=1
11 Calculate contact stress: H
H1=844.1349MPa, H2=844.13491MPa
12 Life factor: ZNT
Stress cycle-index
NL1=4135922, NL2=1482689
According to table 14-1-96
ZNT1=1.387523, ZNT2=1.496649
13 Impact factor of lubricating oil: ZLZVZR
14-1-98 Get gear pair by generating method
according to table 14-1-98
RZ104m, ZLZVZR=0.85
14Working harden factor of tooth surface: ZW
HRC50-55 470HB
Hard tooth surface HRC50-55 is greater than 470HB.
Therefore: ZW=1
15 Size factor: ZX
According to table 14-1-99: ZX=1
16 Safety factor method
SH =HlimZNT ZLZVZRZW ZX H
Therefore: SH1=1.3273
SH1=1.38648
According to table 14-1-100: SHmin = 1.1
Meet requirement.
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7.3.11.4 Bending stress checking of gear
1 Spread factor of helical load: KF=KHN
N=b/h2/[1+b/h+(b/h)2]
There into: b=50, H=2.25m=18
And so, N=0.671321, KF=1.129631
2 Partition coefficient of helical load: KF
KF=KH=1.2
3 Tooth profile coefficient: YF
Equivalent tooth number: zn1=19, zn2=53
According to diagram 14-1-98
YF1=2.9,YF2=2.35
4 Stress correction factor: YS
According to diagram 14-1-103
YS1=1.54, YS2=1.68
5 Contact ratio coefficient: Y
Because: =1, =0
So, Y=1
6 Helical angle coefficient : Y
According to diagram 14-1-109
Y=1
7 Calculation of root stress: F
F= FTYFa YSa Y Y KAKVKF KF
F1=517.305MPa, F2=457.304MPa
8 Stress correction factor of test gear: YST
According to table 14-1-101
YST=2
9 Life factor
YNT =(3000000 NL)0.02, YNT 1= 0.9936, YNT2= 1.014195
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10 Relatively root sensitivity coefficient
According to table 14-1-102 and diagram 14-1-98
YrelT = 1
11 Relatively root surface condition factor
According diagram 14-1-118
RRrelT = 1
12 Size factor: YX
14-1-109 According to the formula of table 14-1-109
YX=1.03-0.006m, YX=0.982
13 Safety factor of bending strength: SF
SF=Flim YST YNT Yrel YRrel YX
SF1=1.32, SF2=1.48
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7.4
Calculation for hang wheel
The maximum wheel-pressure of hang: 2.5t
Gradient: 1%
Running speed: 4m/min
According to above calculation, wheel-pressure of hang is much lesser than
wheel-pressure of launcher roller and they share the same driving system. so the
power's checking computations is positively suitable, just need to check and
calculate strength and speed of hang wheel.
7.4.1 Strength checking of wheel
Diameter of wheel: 160mm
Width of orbit: 30mm
P=1.17X1.13X5.6X160X30=35538 N3.5t
So the wheel is suitable.
7.4.2 Speed checking
Transmission ratio of chain wheel
z2/z1=22/14
And revolving speed of wheel
N=1430/103X19/53X22/14=7.82 r/min
Running speed of wheel
V = Dn 1000 = 7.82 160 1000 = 3.93 m/min
The rate of speed difference
P=4-3.93/4=0.0175