gearbox vibration analysis
DESCRIPTION
Vibration of a gearbox with results and equationsTRANSCRIPT
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Phone: +44 (0)1206 791917 Email: [email protected] Web: rms-reliability.com
Contents
Case No.1 - Gearwear 1.83 rpm Case No.2 - Chipped Tooth 42 rpm Case No.3 - Gearwear 8052 rpm Case No.4 - Chipped Tooth 1239 rpm Case No.5 - Misaligned Gears 146 rpm Case No.6 - Gearwear 97 rpm Case No.7 - Misaligned Gears 5 rpm Case No.8 - Bearing defect 9 rpm Case No.9 - Bearing defect 231 rpm Cases highlighted in red show the possibilities of vibration provided the information on the machine is correct and a good set-up is used. Selecting the correct sensor is also important.
Gearbox Vibration Analysis
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Vibration Analysis - Gearbox Examples Case No.1 Slow Speed Pulp Press Gearbox Localised Gearwear ( 1.83 rpm Output ) Gearbox measured similar to one above.
WAVEFORM DISPLAY 01-Dec-00 16:44:20 (PkVue- HP 500 Hz) PK = .1410 PK(+) = 1.86 PK(-) = .1044 CRESTF= 18.64
0 10 20 30 40 50 60 70 80
-0.5
0
0.5
1.0
1.5
2.0
Time in Seconds
Acc
eler
atio
n in
G-s
Prs - PULP PRESS 3 STORD 980PULPPRESS3-5RP GBX SHAFT 5 RIGHTFRONT AXIAL PKV
ANALYZE SPECTRUM 01-Dec-00 16:44:20 (PkVue- HP 500 Hz) PK = .1391 LOAD = 100.0 RPM = 2. RPS = .03
0 100 200 300 400 500 600 700
0
0.005
0.010
0.015
0.020
0.025
Frequency in Orders
PK A
ccel
erat
ion
in G
-s
Ordr: Freq: Spec:
58.00 1.770 .01370
M=4TH RED WHEEL : 58.00
M M M
OUTPUT GEARMESH WITH HARMONICS & SIDEBANDS
1 REV 1 REV
Localised damage to output gear
Set-up: Slow speed sensor, Fmax 1200 cpm, 1600 Lines, Acceleration, Magnet mount, PkVue 500 Hz filter, Normal low freq readings taken also.
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Case No.2 Slow Speed Pulp Press Gearbox Chipped Tooth ( 42 rpm second shaft )
WAVEFORM DISPLAY 19-Jan-01 10:21:18 RMS = .0135 PK(+) = .0827 PK(-) = .1050 CRESTF= 7.75
0 1 2 3 4 5 6 7
-0.12-0.09-0.06-0.030.000.030.060.090.12
Time in Seconds
Acc
eler
atio
n in
G-s
PULP - PULP PRESS NO237PRSS0002-L2S GBOX 1st SET LEFT (320L MAG) STD
ROUTE SPECTRUM 19-Jan-01 10:21:18 (SST-Corrected) OVERALL= .0133 A-DG RMS = .0133 LOAD = 100.0 RPM = 41. RPS = .69
0 4000 8000 12000 16000
0
0.001
0.002
0.003
0.004
0.005
Frequency in CPM
RM
S A
ccel
erat
ion
in G
-s
Freq: Ordr: Spec:
704.80 17.00 .00010
E=GMF 17T : 704.8
E E E E E E E E E E
HARMONICS OF GEARMESH WITH SIDEBANDS @42CPM
ONCE PER REV IMPACT (CHIPPED TOOTH)
Set-up: Slow speed sensor, Fmax 14000 cpm, 6400 Lines Res, Acceleration, Magnet mount, SST Enabled. PkVue also taken. Case No.3 High Speed 13MW Steam Turbine Gearbox Input Gearwear ( 8052 rpm Input )
WAVEFORM DISPLAY 17-Jan-01 13:54:14 PK = 19.32 PK(+) = 33.69 PK(-) = 42.78 CRESTF= 3.13
0 40 80 120 160 200 240 280 320
-50-40-30-20-10
0102030
Time in mSecs
Acc
eler
atio
n in
G-s
43 - Steam Turbine 13MWTurb -2V Turbine DE Vertical
Label: HIGH GEARMESH WITH SIDEBANDS
ANALYZE SPECTRUM 17-Jan-01 13:54:14 RMS = 13.25 LOAD = 55.0 RPM = 8052. RPS = 134.20
0 4 8 12 16 20 24 28 32 36 40
0
1
2
3
4
5
67
Frequency in Orders
RM
S Ve
loci
ty in
mm
/Sec
1.00
25.0
0
25 Tooth input gear withfault sidebands at 8052 cpm
1xrpm
HIGH G LEVELS IN WAVEFORMOrdr: Freq: Spec:
25.00 3354.7 4.539
Set-up: Fixed sensor, Fmax 650000 cpm, 6400 Lines Res, Acceleration.. PkVue also taken.
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Case No.4 Reduction Gearbox Chipped Tooth ( 1239 rpm )
ROUTE WAVEFORM 10-MAY-99 15:31:33 RMS = 1.97 PK(+) = 13.16 PK(-) = 14.53 CRESTF= 7.39
0 60 120 180 240 300
-18-15-12
-9-6-3
0369
12
Time in mSecs
Acc
eler
atio
n in
G-s
Fts - Gearbox ( CHIPPED TEETH )Gearbox -GIV GEARBOX INPUT VERTICAL DE
ROUTE SPECTRUM 10-MAY-99 15:31:33 OVRALL= 4.80 V-DG RMS = 4.76 LOAD = 100.0 MPM = 794. RPM = 1239.
0 20000 40000 60000 80000 100000
0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.42.7
Frequency in CPM
RM
S Ve
loci
ty in
mm
/Sec
Freq: Ordr: Spec:
1238.8 1.000 1.052
J=GMF : 33.46K
J J
Low level sidebands surround gearmesh
Once per rev impacting ( Waveform Key to analysis)
Set-up: Standard Magnet sensor, Fmax 90000 cpm, 6400 Lines Res, Vel, Acceleration.
ANALYZE WAVEFORM 10-MAY-99 09:46:16 (PkVue-HP 1000 Hz) RMS = 9.06 PK(+) = 75.36 PK(-) = 6.16 CRESTF= 8.32
0 100 200 300 400 500 600 700 800
-20
0
20
40
60
80
Time in mSecs
Acc
eler
atio
n in
G-s
Fts - Gearbox ( CHIPPED TEETH )Gearbox -GIV GEARBOX INPUT VERTICAL DE
Label: PKVUE CHIP TOOTH
ANALYZE SPECTRUM 10-MAY-99 09:46:16 (PkVue-HP 1000 Hz) RMS = 8.51 LOAD = 100.0 MPM = 875. RPM = 1365.
0 20000 40000 60000
0
1
2
3
4
5
6
Frequency in CPM
RM
S A
ccel
erat
ion
in G
-s
Typical Faulty Gear Spectrum ( PkVue )
Waveform once per rev impactFreq: Ordr: Spec:
1365.3 1.000 4.279
Set-up: Same fault as prev, Standard Magnet Sensor. Fmax 60000cpm, Accl, PkVue 1000Hz Filter 6400 Lines.
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Case No.5 Ball Mill Output Gears Misaligned Gears ( 146 rpm )
Fts - Gearbox ( MISALIGNED GEARS )Misalign -B2H Output bearing outboard horiz
Label: Misaligned gears / worn input
ROUTE SPECTRUM 14-DEC-99 14:25:02
OVRALL= 4.84 V-DG RMS = .4014 LOAD = 100.0 RPM = 147. RPS = 2.44
0 4000 8000 12000
0
0.1
0.2
0.3
0.4
0.5
Frequency in CPM
RM
S A
ccel
erat
ion
in G
-s
MISALIGNED OUTPUT GEARS
3XGMF
2XGMF
Freq: Ordr: Spec:
2784.9 19.00 .03485
1XGMF Wear sidebands @ 146 rpm
Set-up: Standard Magnet sensor, Fmax 10000 cpm, 6400 Lines Res, Acceleration.
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Case No.6 Extruder Gearbox Damaged Gear ( 97 rpm )
WAVEFORM DISPLAY 11-MAR-98 14:56:28 RMS = .0106 PK(+) = .0319 PK(-) = .0320 CRESTF= 3.02
0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7
-0.05
-0.04
-0.03
-0.02
-0.01
0
0.01
0.020.03
Time in Seconds
Acc
eler
atio
n in
G-s
Fts - Ext - ( GEARWEAR )Gearwear -G2A Gearbox Input Outboard Axial
Label: Gearwear 59 tooth gear
ANALYZE SPECTRUM 11-MAR-98 14:56:28 RMS = .0112 LOAD = 100.0 RPM = 97. RPS = 1.61
0 4000 8000 12000 16000 20000
0
0.001
0.002
0.003
0.004
Frequency in CPM
RM
S A
ccel
erat
ion
in G
-s
Freq: Ordr: Spec:
5706.7 59.00 .00199
B=59 teeth : 5707.
B B B
GEARMESH WITH SIDEBANDS @ 97 CPM
Set-up: Standard Magnet sensor, Fmax 18000 cpm, 6400 Lines Res, Acceleration. Case No.7 Diffuser Gearbox Misaligned Gears ( 5 rpm )
ROUTE WAVEFORM 05-FEB-01 14:47:24 PK = .0045 PK(+) = .0090 PK(-) = .0100 CRESTF= 3.14
0 20 40 60 80 100 120 140 160
-0.012
-0.008
-0.004
0.000
0.004
0.008
0.012
Time in Seconds
Acc
eler
atio
n in
G-s
DG - Diffuser Gearbox Citreon MesStream C -29H GBX 5th SHAFT MTRSIDE HORIZ
ROUTE SPECTRUM 05-FEB-01 14:47:24 (SST-Corrected) OVRALL= .0046 A-DG PK = .0046 LOAD = 100.0 RPM = 5. RPS = .08
0 100 200 300 400 500 600
0
0.0008
0.0016
0.0024
Frequency in CPM
PK A
ccel
erat
ion
in G
-s
Freq: Ordr: Spec:
126.37 25.12 .00005
J=Output Gear 25 : 125.8
J J J J
3xgmfMisaligned Gears
2xgmf1xgmf
Set-up: Slow speed sensor, Fmax 600 cpm, 1600 Lines Res, Acceleration, Magnet mount, SST Enabled. PkVue also taken.
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Case No.8 Slow Speed Diffuser Gearbox Bearing Defect ( 9 rpm shaft )
ANALYZE WAVEFORM 19-DEC-00 11:23:07 PK = .0036 PK(+) = .0123 PK(-) = .0141 CRESTF= 5.48
0 3 6 9 12 15 18 21 24 27 30 33
-0.018
-0.012
-0.006
0.000
0.006
0.012
0.018
Time in Seconds
Acc
eler
atio
n in
G-s
DG - Diffuser Gearbox ShackletonStream B -27A GBX 4th SHAFT MTRSIDE AXIAL
ANALYZE SPECTRUM 19-DEC-00 11:23:07 (SST-Corrected) PK = .0007 LOAD = 100.0 RPM = 9. RPS = .16
0 400 800 1200 1600
0
0.00004
0.00008
0.00012
Frequency in CPM
PK A
ccel
erat
ion
in G
-s
Freq: Ordr: Spec:
104.26 11.20 .00001
>SKF 24052C D=BPFO : 104.5
D D D D D D D D D D D D
Impacting matches outer race impact freq
Set-up: Slow speed sensor, Fmax 3000 cpm, 3200 Lines Res, Acceleration, Magnet mount, SST Enabled. PkVue also taken.
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Case No.9 Reduction Gearbox Bearing Defect ( 231 rpm shaft ) Set-up: Slow speed sensor, Fmax 30000 cpm, 6400 Lines Res, Acceleration, Magnet mount, PkVue 500 Hz Filter. Reliability Maintenance Solutions Ltd Email : [email protected] Websites: www.rms-training.com & www.rms-reliability.com Head Office : +44 (0)1206 791917
Vibration Analysis - Gearbox Examples Case No.1 Slow Speed Pulp Press Gearbox Localised Gearwear ( 1.83 rpm Output ) Head Office : +44 (0)1206 791917