JA-5_Appx_4_Tab_03 _Vibration_ _Run-out.pdf

1 2 1 2 0 D R Y C R E E K R O A D

A U B U R N , C A 9 5 6 0 2

( 5 3 0 ) 3 9 2 - 3 4 3 5

K E N M A R I N S T R U M E N T A T I O N S E R V I C E S

April 21, 2011:

Mr. Jeremy Craytor Tetrad Services 960 Diamond Ave.

Red Bluff, CA 96080

SUBJECT: Shutdown Data Collection and Analysis: Eielson AFB STG3

Machine Train – April 8th, 2011.

Mr. Craytor, KenMar Instrumentation Services was hired by Tetrad Services to record vibration readings at Eielson AFB for the STG3 Machine Train. This data was recorded during shutdown of the unit prior to disassembly. During this time, KenMar recorded thrust bearing and total float clearance readings and recorded vibration levels at full speed and no load, 1 MW, 3 MW and 4 MW.

A Bently Nevada ADRE 208 data acquisition interface unit was provided by KenMar and was connected to the customer’s existing vibration monitor to pick up outputs from the unit’s existing vibration probes.

The data collected was collected on April 8, 2011, when data was captured in incremental loading up to 4 Megawatts generation, and shutdown to rotor stop, and the report of the data analysis was completed April 20th.

Please find the data analysis report enclosed.

If I may be of further assistance, please do not hesitate to call.

Sincerely, Alaric Scott KenMar Instrumentation Services 12120 Dry Creek Road Auburn, CA USA 95602

(530) 392-3435 Phone

(530) 392-3436 Fax www.kenmarllc.com

Data Analysis: Eielson AFB STG3 Machine Train Shutdown Report

KenMar Instrumentation Services was hired to record vibration readings at Eielson AFB on the STG3 Machine Train. This data was recorded on April 8th, 2011 during shutdown of the unit, while the unit was in operation, prior to disassembly of the unit. Shutdown occurred on April 8th, 2011.

During this time, KenMar recorded thrust bearing and total float clearance readings and recorded vibration levels at full speed and no load, 1 MW, 3 MW and 4 MW using a Bently Nevada ADRE 208 data acquisition interface unit The was provided by KenMar and was connected to the customer’s existing vibration monitor to pick up vibration buffered outputs from the unit’s existing vibration probes.

The data analyzed shows severe shaft surface run-out on the Turbine Outboard (bearing 1) in excess of 4 mils. Further inspection during machine disassembly showed that the probe target area was observing part of the Keyphasor notch and rotor shoulder edge.

Additionally, the data collected on Turbine Inboard (bearings 2) indicates high shaft surface run-out. The cause of this appears to be due the non-burnished surface observed by the vibration probe.

The job scope requires returning to the job site during reassembly to perform the following:

Inspect the existing vibration monitoring system (Bently Nevada 3500).

Check and adjust, if necessary, the alarm and shutoff system.

Verify proper functioning of Proximitors.

Inspect condition of cable sand insulation between monitor rack and probes.

Replace all Proximitor probes.

Recommend additional repairs if necessary.

Replace Three speed pick-ups connected to the Turbo-Sentry with Magnetic Pickups Dynalco Model M203.

Recommendations

Based on the stated conclusions the following recommendations are made:

Bearing probe target areas should have the mechanical runout removed at the next possible opportunity. The preferred method of correcting this situation is to burnish, or polish the probe observation area on the shaft.

Removal of these scratches/imperfections is critical in order to acquire accurate vibration readings. CAUTION: Using emery cloth in an attempt to remove the glitch will only aggravate the problem. To aid in the correction of this situation, a detailed, step-by-step procedure for removal of runout is included for your information.

Experience has shown that if mechanical runout is removed properly, the total runout value can definitely be reduced to less than 7 microns, Pk-Pk which is maximum allowable according to API, the American Petroleum Institute.

Attached Data:

Speed Trace Plot

Trend Plots showing Turbines individual points versus speed.

o Run-out Uncompensated o Run-out Compensated

Orbit/Timebase plots for Turbines individual bearings at full load.

o Run-out Uncompensated o Run-out Compensated

If I may be of further assistance, please do not hesitate to call.

Sincerely, Alaric Scott KenMar Instrumentation Services

Speed Trace: GREEN – Steady State

BLUE – Overspeed RED – Coast Down

Tetrad

Eielson AFB

August 5, 2011

Steam Turbine/Generator

Vibration Probe Run-out Test Data Report

This report summary contains data collected during the Testing of the Steam Turbine Rotor and the

Generator Rotor for Journal run-out.

The testing took place at Tetrad in Red Bluff, CA on July 28, 2011.

The scope of this report contains the test data;

1. Waveform data for each Journal

a. Turbine Outboard

b. Turbine Inboard

c. Generator Inboard

d. Generator Outboard

2. Static Data for each Journal

a. Turbine Outboard & Inboard

b. Generator Outboard & Inboard

3. Shaft Surface Probe Curve Data

a. Turbine Shaft

b. Generator Shaft

S A F E T Y F I R S T

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A U B U RN , C A 9 5 6 0 2

P HONE : ( 5 3 0 ) 3 9 2 - 3 4 3 5 • F A X : ( 5 3 0 ) 3 9 2 - 3 4 3 6

Turbine Rotor - OB BRG - Horizontal - Dis Spec/Wfm 24000 CPM

7/28/2011 6:23:11 PM

secs

0 2 4 6 8 10 12 14 16 18 m ils

-0.4

-0.2

0.2

0.4

O/All 0.4241 mils pk-pk

True pk-pk 0.9799 mils

Crest Factor 3.268

7/28/2011 6:23:11 PM O/All 0.4241 mils pk-pk <set RPM>

Turbine Rotor - IB BRG - Horizontal - Dis Spec/Wfm 24000 CPM

7/28/2011 7:02:33 PM

secs

0 2 4 6 8 10 12 14 16 18 m ils

-0.4

-0.3

-0.2-0.2

-0.1

0.1

0.2

0.3

0.4 O/All 0.2953 mils pk-pk

True pk-pk 0.6749 mils

Crest Factor 3.232

7/28/2011 7:02:33 PM O/All 0.2953 mils pk-pk <set RPM>

Gen Rotor - IB BRG - Horizontal - Dis Spec/Wfm 24000 CPM

7/28/2011 12:44:23 PM

secs

0 2 4 6 8 10 12 m ils

-0.6

-0.4-0.4

-0.2

0.2

0.4

O/All 0.5339 mils pk-pk

True pk-pk 0.775 mils

Crest Factor 2.053

7/28/2011 12:44:23 PM O/All 0.5339 mils pk-pk <set RPM>

Gen Rotor - OB BRG - Horizontal - Dis Spec/Wfm 24000 CPM

7/28/2011 11:42:21 AM

secs

0 2 4 6 8 10 m ils

-0.6

-0.4-0.4

-0.2

0.2

0.4

0.6

O/All 0.4395 mils pk-pk

True pk-pk 0.6767 mils

Crest Factor 2.177

7/28/2011 11:42:21 AM O/All 0.4395 mils pk-pk <set RPM>

Date:

Machine:

0 0.514

5 0.621 0.107

10 1.378 0.757 0%

15 2.374 0.996 0%

20 3.388 1.014 1%

25 4.412 1.024 2%

30 5.41 0.998 0%

35 6.426 1.016 2%

40 7.459 1.033 3%

45 8.474 1.015 2%

50 9.476 1.002 0%

55 10.472 0.996 0%

60 11.482 1.01 1%

65 12.487 1.005 1%

70 13.512 1.025 3%

75 14.494 0.982 -2%

80 15.485 0.991 -1%

85 16.502 1.017 2%

90 17.525 1.023 2%

95 18.566 1.041

100 19.612 1.046

Eielson AFB

Range End: 90mils / 17.525Vdc

Gap Voltage

Alaric Scott

Sensitivity = 201.84 mV/mil

Extension Model#

Target Material

Probe Orientation

2011021Work Order #:

Driver Model# / Serial#

Plant:

Customer & Contact:

Location on Machine

Range in Mils Voltage

Voltage

Difference

Linear

Deviation:

[Spec = +/-

5%]

KenMar Rep(s):

July 28, 2011

Range Start: 10mils / 1.378Vdc

Probe Model#

Turbine Rotor

Extension Serial#

Probe Serial#

KenMar Instrumentation Services, LLC 12120 Dry Creek Road, Auburn, CA 95603

Phone: (530) 392-3435 Fax: (530) 392-3436

Proximity Transducer Calibration Tetrad

Observed Range: (Only modified for transducer systems with variable or short ranges such as the Bently Nevada 3000 series.)

Alert / Danger

0.00

5.00

10.00

15.00

20.00

25.00

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

O U

T P

U T

V O

L T

A G

E

RANGE IN MILS

PROBE CALIBRATION GRAPH

0.90

0.92

0.94

0.96

0.98

1.00

1.02

1.04

1.06

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

A c c u ra c y

Date:

Machine:

0 0.594

5 0.594 0

10 1.187 0.593 0%

15 2.253 1.066 7%

20 3.303 1.05 5%

25 4.325 1.022 2%

30 5.318 0.993 -1%

35 6.359 1.041 4%

40 7.386 1.027 3%

45 8.414 1.028 3%

50 9.447 1.033 3%

55 10.486 1.039 4%

60 11.49 1.004 0%

65 12.47 0.98 -2%

70 13.444 0.974 -3%

75 14.417 0.973 -3%

80 15.389 0.972 -3%

85 16.343 0.954 -5%

90 17.28 0.937 -6%

95 18.268 0.988

100 19.216 0.948

KenMar Instrumentation Services, LLC 12120 Dry Creek Road, Auburn, CA 95603

Phone: (530) 392-3435 Fax: (530) 392-3436

Proximity Transducer Calibration Customer & Contact: Tetrad July 28, 2011

Plant: Eielson AFB Work Order #: 2011021

KenMar Rep(s): Alaric Scott Generator Rotor

Range in Mils Voltage

Voltage

Difference

Linear

Deviation:

[Spec = +/-

5%]

Location on Machine

Probe Model#

Probe Serial#

Extension Model#

Extension Serial#

/Driver Model# / Serial#

°Probe Orientation

Sensitivity = 201.16 mV/mil Range Start: 10mils / 1.187Vdc Range End: 90mils / 17.28Vdc

Target Material

/Alert / Danger

Gap Voltage

Observed Range: (Only modified for transducer systems with variable or short ranges such as the Bently Nevada 3000 series.)

0.00

5.00

10.00

15.00

20.00

25.00

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

O U

T P

U T

V O

L T

A G

E

RANGE IN MILS

PROBE CALIBRATION GRAPH

0.85

0.90

0.95

1.00

1.05

1.10

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100

A c c u ra c y

1 2 1 2 0 DRY CREEK ROAD

AUBURN, CA 9 5 6 0 2

August 23, 2011

Mr. Chris Coy

Tetrad Services

960 Diamond Ave.

Red Bluff, CA 96080

SUBJECT: Data Acquisition and Analysis: Eielson AFB STG3, Machine Train

Mr. Coy, KenMar Instrumentation Services was commissioned by Tetrad to acquire vibration data on their Steam Turbine

Generator set No.3 located at Eielson AFB, Fairbanks, Alaska.

The vibration data reviewed and contained within this report is solely for the steady state portion of the run at .25 MW load up to 5MW load and only pertains to that time frame and is not an assessment of the machine trains condition.

At this point in time there are apparent machinery vibration characteristics that appear to be outside of the normal realm of machinery diagnosis. KenMar Instrumentation Services feels a more in-depth analysis is warranted to make an accurate assessment. Should Tetrad request such services KenMar Instrumentation Services would be available to perform this analysis. This analysis should include data from a hot shutdown.

The run designation for that time frame (August 15, 2011) is labeled EAFBtmp4.

Please reference the data discussion that follows.

It has been a pleasure working with the Tetrad personnel and if you have any questions and/or comments, please do not hesitate to call me at: 714-847-2740.

Respectfully Submitted

Ronald D Murphy

Senior Machinery Diagnostics Specialist

KenMar Instrumentation Services

17342 Rob Roy Circle

Huntington Beach, California 92647

(714) 847-2740 Phone

(714) 856-6503 Cell

DISCUSSION of DIRECT DATA

1. A series of Direct (uncompensated and waveform compensated) orbital plots are included for your consideration. The plots were extracted from the beginning of the steady state run at 10:31:00 hrs with an approximate load of 1MW.

a. The direct orbital plot for the turbine outboard end (reference figure 1, page 4 top) exhibits a circular shaped orbit predominantly at the rotational speed (1X) 3600 rpm. The direct vibration amplitudes of

3.99 mil pp and 3.24 mil pp are considered to be highly elevated for a machine operating at 3600 rpm.

b. The direct orbital plot for the turbine inboard end (reference figure 2, page 4 bottom) exhibits a banana shaped orbit characteristic of a bearing with a heavy preload. Also, the direct orbit exhibits a “flat” spot indicative of the shaft being restricted from following its normal path of rotation within the bearing. The most likely cause for this type of response would be associated with a rub, either within the bearing or an adjacent seal or labyrinth.

c. The direct orbital plot for the Generator inboard end (reference figure 3, page 5 top) exhibits a more elliptically shaped orbit with a two times running speed component. This may be the result of glitch and/or the presence of a misalignment condition either internal/external.

d. The direct orbital plot for the generator outboard end (reference figure 4, page 4 bottom) exhibits a figure 8 orbit most often associated with the presence of a misalignment condition. However, this type of response may also be related to the shaft surface condition, (i.e., Non-concentricity, mechanical runout, electrical runout, or a combination of both, etc.)

DISCUSSION of WAVEFORM COMPENSATED DATA

1. The direct, waveform compensated, plot for the turbine outboard end exhibits the presence of one inner loop which suggest the presence of a two (2) times running speed component present. Generally the presence of a 2X running speed component could be the result of internal/external misalignment or could be the result of a shaft surface anomaly such as mechanical runout, electrical runout, and/or a combination of both or some other type of shaft surface imperfection. Also, a 2X running speed component observed in the generator may be present because of the 2 pole design.

2. The direct waveform compensated plot for the turbine inboard end exhibits an elliptically shaped orbit with a ”flat” spot. As stated previously this type of response may be the result of a rub occurring either within the bearing of on an adjacent seal or labyrinth.

3. The direct waveform compensated plot for the generator inboard exhibits an elliptically shaped orbit with the presence of an inner loop. This type of response indicates the presence of a twice running speed component generally associated with the presence of a misalignment condition. . Also, a 2X running speed component observed in the generator may be present because of the 2 pole design.

4. The direct waveform compensated plot for the generator outboard end exhibits a banana shaped orbit generally associated with the presence of a heavy preload restricting the rotor from following its normal path of rotation within the bearing.

Although a significant amount of elect/mech runout is observed on the turbine outboard end, the result of this runout is misleading because of the large amount of slow roll. Therefore, the “slow roll” compensated plots do not provide an accurate picture of the observed vibration characteristics.

However, when “waveform compensation” is applied a more accurate assessment can be offered. In this case there is insufficient data to provide an accurate assessment for this machine train. Also, the absence of axial (thrust) data does not allow for a complete picture. The “EAFBtb2” run (198 rpm to 500 rpm) on 8-10-2011 indicates the rotor axial position to be thrusting in the opposite direction of normal thrust. (Due to equipment limitations the thrust probe position measurements were not acquired).

DISCUSSION for SLOW ROLL

“The basic assumption when using slow roll compensation is that, at running speed, the shaft probes view the same section of rotor surface that they view at slow roll. However, at each axial position on a shaft, the shaft surface is likely to produce a different slow roll vector. All compensated data should be reviewed with caution.

If slow roll compensation is to be used, it should be acquired from a hot shutdown, as hot shutdown slow roll vectors will be less likely to have this problem”.

DISCUSSION for WAVEFORM COMPENSATION

The primary objective of compensation is to remove unwanted signal content (noise) that is unrelated to the machine behavior that we want to observe. Waveform compensation is used within this report to remove the unwanted slowroll and most of the signal artifacts due to shaft surface defects which is most likely masking the true vibration characteristics for this machine.

The Following plots (pages 4 & 5) are direct (uncompensated) 1MW load

Figure 1 Run eafbtmp4 Plot #41 direct orbit Turbine Outboard 1MW load

Figure 2 Run eafbtmp4 Plot #41 Direct orbit Turbine Inboard 1MW Load

Figure 3 Run eafbtmp4 Plot #41 Direct orbit Generator Inboard 1MW Load

Figure 4 Run eafbtmp4 Plot #41 Direct orbit Generator Outboard 1MW Load

The Following plots (pages 6 - 9) are direct (uncompensated Timebase Waveforms).

Figure 1 1MW Load

Figure 2 1MW Load

Figure 3 1MW Load

Figure 4 1MW Load

Figure 5 1MW

Figure 6 1MW

Figure 7 1MW

Figure 8 1MW

The Following plots (pages 10 - 11) are Direct (waveform compensated) 1MW Load

Figure 1 Run eafbtmp4 Plot #41 direct waveform compensated orbit Turbine Outboard 1 MW Load

Figure 2 Run eafbtmp4 Plot #41 direct waveform compensated orbit Turbine Inboard1 MW Load

The Following plots (pages 11 & 12) are direct (uncompensated Timebase Waveforms).

Figure 3 Run eafbtmp4 Plot #41 direct waveform compensated orbit Generator Inboard 1 MW Load

Figure 4 Run eafbtmp4 Plot #41 direct waveform compensated orbit Generator Outboard 1 MW Load

The Following plots (pages 12 - 13) are direct (uncompensated) 5MW load

Figure 1 Run eafbtmp4 Plot #68 direct orbit Turbine Outboard 5MW load

Figure 2 Run eafbtmp4 Plot #68 direct orbit Turbine Inboard 5MW load

Figure 3 Run eafbtmp4 Plot #68 direct orbit Generator Inboard 5MW load

Figure 4 Run eafbtmp4 Plot #68 direct orbit Generator Outboard 5MW load

The Following plots (pages 14 & 15) are Direct (waveform compensated) at 5MW Load.

Figure 1 Run eafbtmp4 Plot #68 direct waveform compensated orbit Turbine Outboard 5MW Load

Figure 2 Run eafbtmp4 Plot #68 direct waveform compensated orbit Turbine Inboard 5MW Load

Figure 3 Run eafbtmp4 Plot #68 direct waveform compensated orbit Generator Inboard 5MW Load

Figure 4 Run eafbtmp4 Plot #68 direct waveform compensated orbit Generator Outboard 5MW Load

Turbine Outboard

Comp Waveform at 1MW

Comp waveform at 5MW

Comp waveform at 1MW

Turbine Inboard

Generator Inboard

Generator Outboard