ML13311A744
| ML13311A744 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 10/12/1984 |
| From: | FAILURE ANALYSIS ASSOCIATES, INC. |
| To: | |
| Shared Package | |
| ML13311A746 | List: |
| References | |
| FAAA-84-10-9, NUDOCS 8901190079 | |
| Download: ML13311A744 (18) | |
Text
FaAA-84-10-9 QRSCE STEADY STATE TORSIOGRAPH TEST OF EMERGENCY DIESEL GENERATOR #1 AT SAN ONOFRE NUCLEAR GENERATING STATION Prepared by Failure Analysis Associates Prepared for TDI Diesel Generator Owners Group October 12, 1984 PDR ADOCK 05000)206 p
P DC
TABLE OF CONTENTS Page
1.0 INTRODUCTION
.......................................1 2.0 INSTRUMENTATION.................................................. 1 3.0 PROCEDURE.............................................................1 3.1 Pre-test Calibration and Instrumentation Run-In...........2 3.2 Variable Speed, 0% Load Test.................
3 3.3 Variable Load, Synchronous Speed Tests 3
3.4 Post Test Data Verification and Calibration......................3 4.0 RESULTS.............................. #.......................3 4.1 Calibration data...............................................3 4.2 Variable Speed, No-Load Data.....................................5 4.3 Variable Load Data...............................................5
5.0 CONCLUSION
..................................................... #..5 REFERENCES.......................
................ 7
1.0 INTRODUCTION
The purpose of the torsiograph test of the San Onofre Emergency standby Diesel Generator #1 was to measure and record angular vibrations of the gear train end of the crankshaft.
These measurements have been considered in conjunction with a dynamic analysis of the crankshaft system to assess the maximum steady-state stresses encountered by the crankshaft.
This report deals only with the steady-state responses of the system.
Transient response will be addressed in a separate report.
2.0 INSTRUMENTATION The instruments used were an HBM Torsiograph, a Sangamo data recorder, a tachometer, signal conditioners and cabling as listed specifically in the approved TDI Owner's Group procedures [Ref 1].
The torsiograph was attached to the gear-train end of the crankshaft in order to measure the angular vibrations of the free end of the crankshaft as the crackshaft rotated.
The angular displacement of the torsiograph is pre sented as a millivolt signal to a signal conditioner which, in.turn, presents an amplified signal to the data recorder.
A tachometer signal in the form of a once-per-revolution pulse was gen erated by an optically coupled transducer that sensed the passing of a mark on the flywheel of the engine. The optical sensor output to a signal conditioner which output to the data recorder.
Additionally, an oscilloscope, digital multimeter and frequency analyzer were available to monitor the functionality of the test devices.
3.0 PROCEDURE The torsiograph test was performed in accordance with an approved procedure provided by the TDI Owner's Group [Ref.
1] with input from both Failure Analysis Assoicates and TDI.
The test consisted of the following four stages:
- 1. Pre-test calibration.
- 2. Variable speed tests at 0% load.
- 3. Variable load tests at rated speed.
- 4. Post-test calibration.
3.1 Pre-test Calibration and Instrumentation Run-in The pre-test calibration was accomplished by introducing known signals at the sensors.
The data recorder was calibrated by introducting a known signal directly into each active channel.
The calibration signal of each channel was verified by playing back the recording.
The torsiograph was calibrated by displacing the internal sensing mass of the device against internal stops with a magnet supplied by the manufactur er and in accordance with the manufacturer's instructions [Ref.
2].
The resulting output signal is the calibration signal which was played back for verification.
The test documentation information contained in Table 3.1 was logged.
The final pre-test calibration step was to operate the diesel engine for approximately ten minutes at full load while data was being recorded.
The recorded data was examined to verify that the instrumentation and recording system were operational.
3.2 Variable Speed, No Load Tests The engine was operated for five minutes at rated speed and no load.
The speed was then adjusted using the mechanical governor to operate at speeds between 310 and 370 and at 450 rpm.
Emphasis was placed upon testing in the 310-370 rpm range to verify the predicted frequency of the 3-1/2 order harmonic, thereby confirming the analytical model.
The engine was operated at each speed step for two to five minutes while the torsiograph output was recorded. The engine speed and tape footage were recorded (Table 3.2).
3.3 Variable Load, Synchronous Speed Tests The engine was brought to operating speed.
The load was adjusted successively to operate at the following load conditions for two to five minutes:
50%, 75%, 96% and 100%.
The load, current, speed, and tape footage were recorded (Table 3.3).
3.4 Post Test Data Verification and Calibration Selected data records were played back to verify proper measurement and recording.
The calibration procedure outlined above was repeated and the signals recorded.
4.0 RESULTS 4.1 Calibration Data The pre and post test static calibration data are shown in Tables 4.1 and 4.2. The torsiograph sensitivity was calculated as follows:
Voltage Amp. Range (output, V( Setting,
/
Torsiograph Sensitivity, mV/V t
0V degree Input, degrees Thus, the pre-test sensitivity was:
.(5.672)
(50/10) mV/V Torsiograph Sensitivity =
6 4.73 (01rm e
.1%
6 degree The sensitivity for the post test calibration was found to be 4.76 mV/V degree The multiplication factors used in data reduction were calculated as follows:
Amp.
Range Vibration Tape Deck*
(Setting, lV
)
Output, Vpk 1
1Vpk Amplitude
=
(degrees-pk)
(Tape Deck Gain, Torsiograph mV/V Vout/Vin Sensitivity, degree 50 mV/V where Amp. Range Setting =
10 Vpk Tape Deck Gain =
1.005 Vout/Vin [Ch. 3]
0.338 Vout/Vin [Ch. 12]
Thus, for time domain response
[Ch. 3]
Input, degrees-pk = (Output, Vpk) (1.052 degrees-pk Vpk
[Ch. 12]
Input, degrees-pk = (Output, Vpk) (3.127degrees-pk E~h.
3.127 Vpk and for frequency domain response
[Ch. 3]
Input, degrees-pk = (Output, VRMS) (1.488 degrees-pk RMS
[Ch. 12]
Input, degrees-pk = (Output, VRMS) (4.422 degrees-pk RMS For output in VRMS (as in spectral plots) multiply by V2.
4.2 Variable Speed, No-Load Data The variable speed test was performed to determine the natural frequencies of the crankshaft torsional system. The results of this test are shown in Table 4.3.
Figure 4-1 shows that the 3 1/2 order critical speed is reached at 338 rpm. Thus, the first natural frequency is 19.7 Hz.
This is in good agreement with the Holzer calculation of 19.9 Hz made by Delaval and confirmed by Failure Analysis Associates' (FaAA) vibrational analysis [Ref. 3, 4].
The data also reveals the natural frequency of the second mode.
Figure 4-2 graphically describes the amplitudes of the 9 1/2 order response.
The peak at 356 rpm or 56.4 Hz is the manifestation of the second mode natural frequency. This measured response is in good agreement with the Holzer calcu lation of 56.7 Hz made by Delaval and confirmed by FaAA vibrational analysis
[Ref. 3, 4].
4.3 Variable Load Data The variable load test at rated speed was performed to determine the amplitude of vibration as a function of load.
The results of this test are shown in Table 4.4.
Figure 4-3 shows that the amplitude of vibration generally increases with load to a maximum of 0.17 degrees.
The figure also shows the response of the other major orders.
The FaAA vbibration analysis predicted stress levels well below DEMA allowables [Ref. 4, 5].
Since the measured steady state front end amplitudes were less than the FaAA model predicted, it is evident that the steady state stresses are within DEMA allowable limits.
5.0 CONCLUSION
S The following conclusions are made:
The first two natural frequencies of the torsional system are in good agreement with the Failure Analysis Associates analytical model and Delaval Holzer calculations [Ref. 3, 4].
The measured vibrational amplitudes are below those predicted by the Failure Analysis Associates analytical model [Ref. 4].
The stresses projected by the analytical model from the measured vibration response are below DEMA allowables for both single order and combined response at full load.
REFERENCES
- 1.
Torsiograph and Pressure Test Procedure for TDI-20-4 13-Inch by 13-Inch Crankshaft at San Onofre Nuclear Station (Prepared by TDI Owner's Group, September 1984).
SCE Document #S01-FAA-1, Rev. 0.
- 2.
HBM Operating Manual for Rotary Vibration Transducer, 160.03-1.0-1.0e.
- 3.
- Yang, Roland, "Torsional and Lateral Critical Speed, Engine Numbers 75041/42 Delaval-Enterprise Engine Model DSRV-20-4, 6000 kW/8303 BHP at 450 RPM,"
Delaval Engine & Compressor Division, Oakland, California, October 22, 1975.
- 4.
"Evaluation of Emergency Diesel. Generator Crankshafts at Midland and San Onofre Nuclear Generating Stations," FaAA-84-6-54, June 1984.
- 5.
Standard Practices for Low and Medium Speed Stationary Diesel and Gas Engines, Diesel Engine Manufacturers Association, 6th ed., 1972.
- c.
Table 3.1:
TORSIDGRAPH TEST DOCUMENTATION Job Name:
San Onofre Torsiograph Test Date:
9/26/84 Job Number:
PAO 7596, DRSCE Location:
San Onofre Nuclear Power Station Engine
Description:
DG1 Transamerica Delaval Inc.
DGSRV-20-4 Serial No. 75041-2803 C.
Test Personnel:
Steve Riess FaAA Lisa Shusto FaAA Geoff King FaAA Greg Beshouri TDI Table 3.2:
TORSIOGRAPH VARIABLE SPEED TEST Test Personnel:
Steve Riess FaAA Date:
9/26/84 Lisa Shusto FaAA Geoff King FaAA Greg Beshouri TDI Test Speed (RPM)*
Tape Footage 310 910-949 320 956-993 330 1001-1037 335 1050-1085 340 1099-1137 345 1145-1179 350 1190-1220 360 1231-1275 370 1282-1321 450 1329-1399 Table 3.3: TORSIOGRAPH VARIABLE LOAD TEST Test Personnel:
Steve Riess FaAA Date:
9/26/84 Lisa Shusto FaAA Geoff King FaAA Greg Beshouri TDI Test Speed:
450 rpm Load (Kw)
Current (Amp)
Tape Footage 3000 (50%)
410 1737-1826 4500 (75%)
613 2292-2372 5800 (96%)
not recorded 1963-2112 6000 (100%)
801 2249-2280 I.
Table 4.1: PRE TEST STATIC CALIBRATION Static Voltage HBM Signal Cond. Setting Static oltageRana Input Output (mVnir U
(degrees)
(Vdc)T 0
-. 004 50 5
+3 2.852 50 5
0
.001 50 5
-3
-2.820 50 5
0
-.008 50 5
+3 2.853 50 5
0
-. 005 50 5
-3
-2.820 50 5
0
-.014 50 5
Table 4.2:
POST TEST STATIC CALIBRATION HBM Signal Cond. Setting Static Voltage Ranae Input Output (mV)
U (degrees)
(Vdc) 0
.022 50 5
+3 2.878 50 5
0
.028 50 5
-3
-2.837 50 5
0
.018 50 5
+3 2.875 50 5
0
.028 50 5
-3
-2.837 50 5
0
.016 50 5
Table 4.3:
VARIABLE SPEED RESPONSE OF EDG 1A Amplitude of free-end vibration (millidegrees) for given speed (rpm)
Order 310 320 330 335 340 345 350 360 370 0.5 17 20 17 22 22 19 18 19 26 1.0 3
2 2
4 2
4 2
1 2
1.5 9
9 9
9 10 9
10 10 10 2.0 2
3 3
3 4
4 4
5 5
2.5 3
3 3
3 3
3 3
3 3
3.0 0
0 1
1 0
0 1
2 4
3.5 27 37 89 193 187 105 58 28 19 4.0 9
5 3
4 2
2 2
2 2
4.5 64 51 39 35 32 31 28 23 20 5.0 48 42 37 35 33 32 30 28 26 5.5 9
7 6
5 4
4 3
3 2
6.0 4
4 4
4 4
4 4
4 4
4 6.5 0
0 0
0 0
0 0
0 0
7.0 0
0 0
0 0
0 0
0 0
7.5 0
0 0
0 0
0 0
0 0
8.0 0
0 0
0 0
0 0
1 1
8.5 0
0 0
0 0
0 0
0 1
9.0 1
1 1
1 1
2 2
3 4
9.5 2
2 3
4 5
6 9
10 6
10.0 1
3 4
5 4
3 2
1 1
10.5 5
3 2
1 1
1 1
1 1
11.0 4
1 0
0 0
0 0
0 0
11.5 1
0 0
0 0
0 0
1 1
Total 135 130 180 255 260 165 115 100 95 Table 4.4:
VARIABLE LOAD RESPONSE OF EDG 1A Amplitude of free-end vibration (millidegrees) for given load (kw)
Order 0
3000 4500 5800 6000 0.5 22 41 70
- 64.
69 1.0 2
4 3
4 3
1.5 10 18 22 24 21 2.0 14 16 17 18 17 2.5 9
27 32 37 31 3.0 6
3 8
11 8
3.5 3
4 6
7 5
4.0 1
2 2
2 2
4.5 4
6 8
9 8
5.0 17 27 33 37 32 5.5 4
6 7
8 7
6.0 6
9 11 12 11 6.5 0
1 0
0 0
7.0 1
3 4
4 3
7.5
.2 2
2 3
2 8.0 1
1 1
2 1
8.5 0
0 0
1 0
9.0 0
1 0
0 0
9.5 1
1 1
2 1
10.0 0
1 1
1 1
10.5 1
1 1
0 1
11.0 0
1 1
1 1
11.5 0
1 1
1 1
Total 90 125 160 165 140 400 i
I 0 Total response D 3 1/2 order response v
4 1/2 order response 300 Z. 200 C
00 20 300 310 320 330 340 350 -
360 370 380 ENGINE SPEED (rpm)
Figure 4-1.
Variable speed response of San Onofre DG #1.
FaAA-84-10-9
00 0
150 -2 5
7 0
- 0
- h.
Q a 0 9
5 C*
0 I
I l
a*
i I
- l e
I 300 325 350 375 400 ENGINE SPEED (rpm)
Figure 4-2.
94 order variable speed response of San Onofre DG #1.
0 FaAA 10-9
250 O Total response 1o 1/2 order response 200 S2 1/2 order response e'
- 0.
O 150 E
100 LE 60 0
25 60 75 100 ENGINE LOAD (%
Figure 4-3. Variable load response of San Onofre DG #1.
FaAA-84-10-9