1. N I S H AT D Y I N G M I L L S LT D , P O W R H O U E
VIBRATION ANALYSIS REPORT
OF TURBO GENERATOR
21-May-2016
Taqi ud Din Haider

2. MACHINE SCHEMATIC DIAGRAM

3. SR #
Measuring’
s points
Point description
Vibration
100% Load
Remakes
1 T1A Turbine Axial S-1 C-1 21.68 Microns Within the limit
2 T2A Turbine Axial S-1 C-2 21.29 Microns Within the limit
3 T1X Turbine Outboard X S-2 C-1 22.74 Microns Within the limit
4 T1Y Turbine Outboard Y S-2 C-2 19.02 Microns Within the limit
5 T2X Turbine Inboard X S-2 C-3 13.40 Microns Within the limit
6 T2Y Turbine Inboard Y S-2 C-4 9.805 Microns Within the limit
7 G1X Shaft 01 Inboard X S-3 C-1 9.316 Microns Within the limit
8 G1Y Shaft 01 Inboard Y S-3 C-2 6.373 Microns Within the limit
9 G4X Shaft 02 Outboard X S-3 C-3 30.85 Microns Within the limit
10 G4Y Shaft 02 Outboard Y S-3 C-4 63.24 Microns Moderate
11 G6X Generator Inboard X S-4 C-1 46.26 Microns Moderate
12 G6Y Generator Inboard Y S4 C-2 95.79 Microns Moderate
13 G7X Generator Outboard X S-4 C-3 60.95 Microns Moderate
14 G7Y Generator Outboard Y S-4 C4 87.71 Microns Moderate
OVERALL VIBRATION LEVEL

4. ISO 10816-13 VIBRATION SEVERITY CHART

5. REPORT SUMMARY
Plant Nishat Dying
Location Unit-42
Equipment Turbo Generator 06 MW
Health Status Moderate
Explanation:
Machine vibration found within the acceptable limits as per ISO 10816-3
but orbit analysis are showing irregular shape
Please follow the report for detail analysis

6. OBSERVATIONS
 Observed Internal loop in unfiltered orbit of both bearings
of Generator
 Found .5X in X and Y spectra of Gen. bearing

7. ANALYSIS
 In spectrum harmonics of 1 X turning speed of generator
is an indication of excessive clearance in the bearing
 Dominant peak of 0.5 X in spectra of both bearings is
clear indication of internal rub.
 Elliptical shape with inner loop of the orbit plots is an
indication of oil whirl because of instable lubrication film
b/w bearing and journal

8. RECOMMENDATIONS
 Please inspect the both bearing of generator at priority
 Replace the bearing if found excessive clearance / rub
 Measure the vibration and check the vibration spectra once a
month at least, and conduct the oil and wear analysis on
monthly basis to monitor the bearing health

9. FFT VIBRATION SPECTRAMS & TWF
RouteWaveform
21-May-16 11:41:24
P-P = 106.53
PK(+/-)=54.33/67.23
CRESTF=1.87
0 1 2 3 4 5
-80
-40
0
40
80
RevolutionNumber
DisplacementinMicrons
PGH -Steam Turbine6MW
ST-6MW -015 Gen. InboardX Radial, S4-C1
RouteSpectrum
21-May-16 11:41:24
OVERALL=100.86D-DG
P-P = 100.37
LOAD = 80.0
RPM=3000.(50.00Hz)
0 5 10 15 20
0
30
60
90
120
FrequencyinOrders
P-PDispinMicrons
.50
1.00
1.50
2.00
2.50
3.00
3.18
4.00
6.00
7.00

10. FFT VIBRATION SPECTRAMS & TWF
RouteWaveform
21-May-16 11:41:24
P-P = 66.05
PK(+/-)=46.69/29.91
CRESTF=2.02
0 1 2 3 4 5
-40
-30
-20
-10
0
10
20
30
40
50
RevolutionNumber
DisplacementinMicrons
PGH -Steam Turbine6MW
ST-6MW -016 Gen. InboardY Radial, S4-C2
RouteSpectrum
21-May-16 11:41:24
OVERALL=65.42D-DG
P-P = 65.19
LOAD = 80.0
RPM=3000.(50.00Hz)
0 5 10 15 20
0
10
20
30
40
50
60
70
80
FrequencyinOrders
P-PDispinMicrons
.50
1.00
1.50
2.00
3.00
3.18
4.00
5.00
6.00
7.00

11. FFT VIBRATION SPECTRAMS & TWF
RouteWaveform
21-May-16 11:41:24
P-P = 45.35
PK(+/-)=30.35/27.10
CRESTF=2.01
0 1 2 3 4 5
-30
-20
-10
0
10
20
30
40
RevolutionNumber
DisplacementinMicrons
PGH -Steam Turbine6MW
ST-6MW -017 Gen. OutboardX Radial,S4-C3
RouteSpectrum
21-May-16 11:41:24
OVERALL=42.74D-DG
P-P = 42.56
LOAD = 80.0
RPM=3000.(50.00Hz)
0 5 10 15 20
0
10
20
30
40
50
FrequencyinOrders
P-PDispinMicrons
.50
1.00
1.50
2.00
3.00
4.00
5.00
7.00
9.00
10.00

12. FFT VIBRATION SPECTRAMS & TWF
RouteWaveform
21-May-16 11:41:24
P-P = 23.88
PK(+/-)=16.56/14.89
CRESTF=2.03
0 1 2 3 4 5
-20
-15
-10
-5
0
5
10
15
20
RevolutionNumber
DisplacementinMicrons
PGH -Steam Turbine6MW
ST-6MW -018 Gen. OutboardY Radial,S4-C4
RouteSpectrum
21-May-16 11:41:24
OVERALL=23.11D-DG
P-P = 23.00
LOAD = 80.0
RPM=3000.(50.00Hz)
0 5 10 15 20
0
3
6
9
12
15
18
21
FrequencyinOrders
P-PDispinMicrons
.50
1.00
1.50
2.00
3.00
4.00
5.00
7.00
9.00
10.00

13. ORBIT PLOTS

14. IMAGES

15. ORBIT PLOTS AFTER REPAIR