Phone: +44 (0)1206 791917 Email: Info@rms-reliability.com 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

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.

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.

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.

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.

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.

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.

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 : Info@rms-reliability.com 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