ML20080P281
| ML20080P281 | |
| Person / Time | |
|---|---|
| Site: | Palo Verde, 05000000, 05000470 |
| Issue date: | 02/16/1984 |
| From: | ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY |
| To: | |
| Shared Package | |
| ML17298A822 | List: |
| References | |
| CEN-263(V)-NP, NUDOCS 8402220496 | |
| Download: ML20080P281 (66) | |
Text
CEN 263(V).NP A COMPREHENSIVE VIBRATION ASSESSMENT PROGRAM FOR PALO VERDE NUCLEAR GENERATING STATION UNIT 1
{ SYSTEM 80 PROTOTYPE}
PRELIMINARY EVALUATION OF PRE-CORE HOT FUNCTIONAL MEASUREMENT AND INSPECTION PROGRAMS
! N Sk[TYMS COMBUSTION ENGil,EERING. INC.
DO OO
l LEGAL NOTICE THIS REPORT WAS PREPARED AS AN ACCOUNT OF WORK SPONSORED BY COMBUSTION ENGINEERING, INC. NEITHER COM8USTION ENGINEERING NOR ANY PERSON ACTING ON ITS BEHALF:
A.
MAKES ANY WARRANTY OR REPRESENTATION, EXPRESS OR IMPUED INCLUDING THE WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTA88UTY, WITH RESPECT TO THE ACCURACY, COMPLETENESS, OR USEFULNESS OF THE INFORMATION CONTAINED IN THIS REPORT, OR THAT THE USE OF ANY INFORMATION, APPARATUS, METHOD, OR PROCESS DISCLOSED IN THIS REPORT MAY NOT INFRINGE PRIVATELY OWNED RIGHTS;OR B. ASSUMES ANY UA81UTIES WITH RESPECT TO THE USE OF, OR FOR DAMAGES RESULTING FROM THE USE OF, ANY INFORMATION, APPARATUS, METHOD OR PROCESS DISCLOSED IN THIS REPORT.
s
A COMPREHENSIVE VIBRATION ASSESSMENT PROGRAM FOR PALO VERDE NUCLEAR GENERATING STATION UNIT 1 (SYSTEM 80 PROTOTYPE)
PRELIMINARY EVALUATION OF PRE-CORE HOT FUNCTIONAL MEASUREMENT AND' INSPECTION PROGRAMS 5
l TABLE OF CONTENTS SIMIARY i
1.0 SYSTEM 80 MEASUREMENT PROGRAM..............
1-1
1.1 INTRODUCTION
1-1 1.2 CVAP PROGRAM....................
1-1 1.3 ACCEPTANCE CRITERIA................
1-1 2.0 MEASUREMENT PROGRAM...................
2-1 2.1, INTRODUCTION....................
2-1 2.2 INSTRUMENTATION..................
2-1 2.3 DATA ACQUISITION,. '................
2-1 2.4 TEST CONDITIONS..................
2-3 2.5 DATA REDUCTION...................
2-4 2.5.1 CORE BARREL...............
2-4 2.5.2 LOWER SUPPORT STRUCTURE.........
2-5 2.5.3 UPPER GUIDE STRUCTURE..........
2-5 2.6
SUMMARY
2-6 3.0 INSPECTION PROGRAM...................
3-1 3.1 I NTRODU CTI ON....................
3 - 1 3.2 DISCUSSION.....................
3-1 3.3 INSPECTION.....................
3-2 3.3.1 REACTOR VESSEL - CORE SUPPORT BARREL INTERFACES................
3-2 3.3.2 REACTOR VESSEL HEAD - INTERNALS INTERFACES. 3-3 3.3.3 HOLDDOWN RING CONTACT WITH CSB AND UGS..
3-3 3.3.4 CORE BARREL INTERIOR...........
3-4 3.3.5 LOWER SUPPORT STRUCTURE.........
3-4 3.3.6 UPPER GUIDE STRUCTURE..........
3-4 3.3.7 CVAP INSTRUMENTATION...........
3-5 3.4
SUMMARY
3-5 3.5 REACTOR COOLANT SYSTEM AND REACTOR COOLANT PUMP COMPONENT FAILURES..............,...
3-5 i
h-
- i - -
TABLE OF CONTENTS (Cont'd.)
4.0 SUM 4ARY AND CONCLUSIONS.................
4-1 REFERENCES........................ R-1 APPENDIX A PRELIMINARY EVALUATION OF PREDICTED VERSUS MEASURED' PRESSURES............. A-1 ii
TABLES I
Summary of Predicted and Measured Stresses........ viii II Summary of System 80 CVAP Instrumentation......... ix 1.3-1 Response Instrumentation Data Acceptance Criteria....
1-3 2.2-1 CVAP Instrumentation..................
2-7 2.4-1 Original Test Conditions 2-8 2.4-2 Summary of Test Conditions 2-9 2.5-1 CVAP Transducer History.................
2-10 2.5-2 Preliminary CSB Measured CVAP Data...........
2-12 2.5-3 Preliminary LSS Measured CVAP Data...........
2-13 2.5-4 Preliminary UGS Measured CVAP Data...........
2-14 2.6-1 Design, CVAP and Measured Values of Peak Stresses....
2-15 A-1 Comparison of Predicted and Measured RMS Periodic Pressures at 240 Hertz....................... A-3 e
iii
FIGURES I
System 80 Vertical Arrangement 1.1-1 Reactor Vessel Arrangement...............
1-4 1.1-2 Comprehensive Vibration Assessment Program.......
1-5 2.2-1 Transducer Axial Locations...............
2-16 2.2-2 Circumferential Locations of Inlet and Outlet Nozzles..
2-17 2.2-3 CSB:
Input Function Transducers 2-18 2.2-4 CSB: Response Measurement Transducers.........
2-16 2.2-5 LSS:
Instrument Assembly................
2-19 2.2-6 UGS:. Instrumentation for one Quadrant.........
2-20 2.2-7 UGS: Axial Locations for Instrumentation........
2-21 2.3-1 Block Diagram: Data Acquisition System.........
2-22 3.1-1 Reactor Vessel CVAP Inspection.............
3-8 3.1-2 Reactor Internals Assembly CVAP Inspection.......
3-9 3.3-1 CSB Hold Down Ring...................
3-10 3.3-2 Upper Guide Structure Assembly.............
3-11 3.3-3 CEA Shroud Assembly: Top Crack Sunnary.........
3-12 3.3-4 CEA Shroud Assembly: Bottom Crack Summary.......
3-13 A-1 PSD:
P2 at Test Condition 6............... A-3 A-2 PSD:
P12 at Test Condition 6............... A-4 A-3 PSD:
P13 at Test Condition 6............... A-5 A-4 PSD: P2 at Test Condition 11............... A-6 A-5 PSD:
P12 at Test Condition 11
.............. A-7 A-6 PSD: P13 at Test Condition 11
..............A-8 A-7 PSD:
P2 at Test Condition 15............... A-9 A-8 PSD:
P12 at Test Condition 15
.............. A-10 A-9 PSD:
P13 at Test Condition 15
.............. A-11 iv
SIM4ARY In accordance with the United State Nuclear Regulatory Commission, Regulatory Guide 1.20 (Ref. 1), a Comprehensive Vibration Assessment Program (CVAP) has been developed for Palo Verde Nuclear Generating Station Unit 1.
This plant is prototypical of Combustion Engineering's 3800 MWt System 80 pressurized water reactor (Figure I).
The purpose of the CVAP is to verify the structural integrity of the reactor internals to flow induced loads prior to comercial operation. The dynamic flow related loads considered are associated with nomal steady state opera-tion and anticipated operating transients.
This comprehensive program, for a reactor prototype, consists of four indivi-dual Analysis, Measurement, Inspection, and Evaluation progra.as. The Analysis program provides theoretical evidence of the structural integrity of the internals and serves as a basis for both the Measurement and Inspection programs. Results of these programs form a basis for assessing, in the Evaluation program, the margin of safety for the reactor internals. Detailed descriptions of these SC programs are found in Reference 2.
The Evaluation program includes arfalysis and critical review of the data required in both the Measurement and Inspection programs and comparison of these data with predictions of the Analysis program. This evaluation includes an assessment of the methods used to predict the response of the internals to dynamic forces and the resulting margins of safety.
Preliminary and final reports of this evaluation are to be submitted to the Nuclear Regulatory Comission, as specified in Regulatory Guide 1.20, after completion of all precritical testing. This report contains the required preliminary evalua-tion.
Analyses were completed for the flow induced loading dynamic response of the two safety related core support assemblies; the core barrel support assembly (core support barrel and lower support structure) and upper guide structure assembly (Figure I).
Y
Maximum predicted stresses, summarized in Table I, are the alternating stress intensities due to flow induced dynamic loads predicted for CVAP test condi-tions corresponding to normal operation.
A measurement program was developed based on results of these analyses. The purpose of tHs program is to obtain data on both random and deterministic excitation. pressure) and structural response (displacement, strain, accelera-tion).
Instrumentation, consisting of pressure transducers, strain gages, accelerometers, and displacement transducers have been specified for each of the assemblies. A sunnary of the instrumentation is given in Table II.
Pre-core hot functional testing was started on May 13, 1983 and completed July 8, 1983.
Testing was done at steady state and transient (pump startup and shutdown) conditions corresponding to nomal and part loop operation, except for 500*F four pump operation. The period of data acquisition for the CVAP was from May 17 to June 1, 1983. Approximately 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> of pre-core flow testing was 6
completed insuring that the components were subjected to more than 10 cycles of vibration before inspection.
Data was acquired to compare with predicted values of strain and stress.
Transducer signals were conditioned and recorded on magnetic tape for post test reduction and analysis. Response during testing was monitored online and the signals evaluated for spectral content. Root mean square values of the signals related to structural response were computed following each, test and compared to an acceptance criterion based on the endurance stress from the ASME Code. Measured values of stress are listed in Table I at the predicted maximum stress locations.
In all cases the measured values of stress were less than the acceptance limits. Preliminary evaluation of the data show that the measured stresses are less than the predicted values.
A pre-core inspection of the internals was perfomed before initiation and after completion of all pre-core flow tests.
In both cases, the internals were positioned to pemit visual inspection of specified locations (Ref. 2).
Major load bearing surfaces, contact surfaces, welds, maximum stress locations vi
identified in the analysis program and the CVAP instrumentation, mountings, and conduits were examined. A photographic record was made of all observa-tions.
Comparison of results of the visual inspection before and after pre-core testing indicated no signs of abnormal wear or contact for any of the core support structures. However, cracks were found in the heat affected zones near the welds of seven CEA extension shaft guides and ten connecting web locations in the CEA Shroud Assembly. Evidence af these cracks have been reported to the NRC (Ref. 7) and a program has been in progress to determine the cause of the cracking and to institute design modifications. This program is being addressed in a separate report. The CEA shroui package is being instrumented for subsequent testing to verify the adequacy of the design modifications.
Post test disassembly of the reactor coolant circulating pumps revealed damage to the impeller blades on two of the four pumps. Preliminary evaluation of the CVAP data indicates that these blade failures had no significant effect on the magnitude of the flow or the frequency and magnitude of the. periodic pressure pulsations within the reactor during the period of time d'ata was recorded. Thus the hydraulic loads remained unchanged from conditions assumed in predictions of the dynamic response of the internals. These pressure pulsations will be measured during testing of the modified pumps.
vii 1
TABLE I
SUMMARY
OF PREDICTED AND MEASURED STRESSES Values of Predicted Stress Measured Stress Component (psi)
(psi)
Core Support Barrel Lower Support Structure Upper Guide Structure Predicted Stress = Peak alternating stress at CVAP test conditions of 4 pump operation, 564'F.
Measured Stress = 3.0 times root mean square values of measured strain, converted to stress, at CVAP test conditions of 4 pump operation, 564*F.
viii
TABLE II SUMARY OF SYSTEM 80 CVAP INSTRUMENTATION INPUT FUNCTIONS
RESPONSE
MAJOR CDMPONENTS TRANSDUCER PRIMARY FUNCTION QTY. TRANSDUCER PRIMARY-FUNCTION QTY.
Core Support P. T.
Axial Dist.
2 S. G.
Shell Mode Response 4
Barrel 2-0 Accl. 5-300 Hz Response 1
Circumferential Dist.
3 (Beam & Shell Modes)
Coherence Area 2
E. D. D.
0.1-10 Hz Response 3
(Beam Mode)
S. G.
CSB Stress State 4
Below Upper Flange Inlet Pressure 1
Upper Guide P. T.
CEA Shroud Tube Load-2 2-0 Accl. CEA Shroud Tube 5
Structure ing (Max. Crossflow
Response
Velocity Location)
S. G.
CEA Shroud Tube 4
UGS Support Plate 1
Stress State Loading 3-D Accl. Fuel Alignment 1
Plate Vertical and Radial Response Lower Support P. T.
ICI Tube-58 (Max.
1 S. G.
Axial Stress and 2
Structure Turbulent Load)
Response of ICI Tube 58 2-D Accl. Lateral re::ponse 1
of LS$
Sumary Pressure Transducers 13 2-D Accelerometers 7
3-D Accelerometers 1
Eddy Type Disp. Device 3
Straia Gages 14 Total (Input) 13 Total (Response) 25 Total Instruments 38 P. T.
Pressure Transducer S. G.
Strain Gage E. D. D.
Eddy Type Displacement Device Accl.
Accelerometer (2-0, Two Directions, 3-D, Three Directions) ix
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i 1.0 SYSTEM 80 MEASUREMENT PROGRAM
1.1 INTRODUCTION
A comprehensive vibration assessment program (CVAP) has been devel-oped for Palo Verde Nuclear Generating Station Unit 1, in accordance with NRC Regulatory Guide 1.20, Rev. 2 (Ref.1). This reactor is classified as the prototype for Combustion Engineering's System 80 NSSS design. This program, is intended to satisfy the requirements of a CVAP for a prototype reactor as defined in Ref. 1.
Reactor vessel arrangement is shown in Figure 1.1-1.
1.2 CVAP PROGRAM The purpose of the CVAP is to verify the structural integrity of the reactor internals to flow induced vibrations prior to commercial operation. This program was implemented during pre-operational and initial start-up testing of Palo Verde Unit 1.
An overview of the program is snown in Figure 1.1-2.
The CVAP consists of four separate programs (a) analysis program, (b) measurement program, (c) inspection program, (d) evaluation program. Detailed description of these programs are documented in Ref. 2.
This report describes preliminary findings of the measurement and inspection programs. This preliminary report summarizes"and eval-uates the limited processed data and the results of the inspection program with respect to the test acceptance criteria.
1.3 ACCEPTANCE CRITERIA FOR TEST DATA Per Regulatory Guide 1.20 an acceptance criteria is defined for the measured stress. The definition is based on ASME endurance limit stress for fatigue (Ref. 3). The maximum allowable readings for the response instrumentation are specified based on this acceptance criteria.
1-1
It is convenient to define an acceptance criterion that is indepen-dent of the statistical nature of the response and can be applied independent of the particular assembly.
This acceptance criterion is taken as equal to one third the endur-ance stress limit of 26,000 psi, or approximately 8,700 psi. Values of the Acceptance Criteria are listed in Table 1.3-1 taken from Reference 2.
1-2
TABLE 1.3-1 RESPONSE INSTRUMENTATION DATA ACCEPTANCE CRITERIA Instrument Assembly Tjgut Number Criteria
.030 in.
DT A2 to A4
.030 in.
UGS SG S9 to S12 320 micro-in/in AC A5 to A9
.0185 in.
AC A10
.00167 in.
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LSS SG S13, 514 320 micro-in/in AC All
.011 in.
- Limits are all based on 1/3 the endurance limit of 26,000 psi except for the CSB displacement (Al to A4) which is based on the maximum clearance at the snubbers of.015 inches. Acceptance values for the UGS and LSS accelero-meters are based on motion of the assembly relative to the upper guide structure cylinder and the core support barrel, respectively.
SG = Strain Gauge AC = Accelerometer DT = Displacement Transducer 1-3
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I DESIGN CRITERIA CRITERIA PRE TEST PHASE TEST PHASE POST TEST PHASE ANALYSIS REPORT PRELIMINARY TEST EVALUATION REPORT REPORT
l 2.0 MEASUREMENT PROGRAM
2.1 INTRODUCTION
The objective of the measurements program is to obtain sufficient data to confinn predictions for the margin of safety at operating conditions of steady state and transient normal operation. This confirmation requires data related to both the flow induced hydraul-ic loads (forcing functions) and the dynamic response of the struc-tural components. Hence instrumentation is necessary to measure force and response data. This measurements program has been planned with adequate' instrumentation to record the information necessary, with appropriate data reduction, to compare predicted and measured values of response and verify the margin of safety for long term operation.
2.2 INSTRUMENTATION Instrumentation is summarized in Table 2.2-1 with locations shown in Figures 2.2-1 to 2.2-7.
2.3 DATA ACQUISITION 2.3.1 Data Acouisition System.
The CVAP data acquisition system is designed to record on magnetic tape the electrical signals from transducers mounted on the reactor internals. These tape recordings are the inputs used by various off-line processing techniques. The recorded time histories were examined on-line for both amplitude and frequency content.
A schematic of the data acquisiticn system is shown in Figure 2.3-1.
2-1
2.3.2 Data Acquisition Method The three phases of CVAP data acquisition include:
documentation, calibration, and data monitoring.
2.3.2.1 Documentation
~
Each transducer and its associated cables were uniquely identified.
The transducer and cables associated with a signal conditioner wero logged in the transducer hook-up log. This identifies a signal path at every connection from the transducer to tape recorder. The accuracy of this hook-up log was verified by acquisition personnel during instrumentation hook-up and checkout. No deviations from the initial hook-up were made during testing.
2.3.2.2 Calibration The integrity of the transducers and connecting cables was monitored through leadwire insulation and transducer capacitance measurements.
These checks.were made and recorded in the transducer characteris-tics log. Twice a day strain gage transducers were shunt calibrated at the bridge amplifier and these shunt calibration voltages record-ed on the characteristics lag. Overall system calibration were switched into calibrate mode and a short tape recording is made. An entry for each system calibration was made in the CVAP data log.
2.3.2.3 Data Monitoring When a test condition was set and the acquisition system was ready, a data recording was made. The signal level of each transducer channel was monitored while setting the signal conditioning ampli-fier gains for optimum output levels. The strain gage amplifiers were balanced and the sensitivity of all charge amplifier verified.
An entry was then made in the CVAP data log, a sequential test number assigned, tape footage, and time of day noted and all signal conditioning gains entered. Additional coments were made in the data log when necessary.
2-2
A recording session was started with a voice recording on tape detailing the test number, test conditions, data, time, and tape footage. Other pertinent information was included as necessary in the voice recording.
Each signal was monitored on-line to verify the recording process and the adequacy of the data signal level.
2.4 TEST CONDITIONS Internal vibration data required for the CVAP was obtained at Palo Verde from May 15 to June 3 during pre-core hot functional testing.
Thirty-eight (38) instruments, with a total of forty-seven (47) channels of data, were monitored during various temperature plateaus and pump combinations.
The test procedure and acceptance criteria was incorporated into the Arizona Public Service (APS) Hot Functional Test Procedure (Ref. 4).
This procedure also specified the use of APS personnel to act as a test coordinator and QA/QC inspector.
The original test conditions are specified in Table 2.4-1.
Data for conditions 1 through 8 was obtained without difficulty with the exception of substitution of Pump 2-B for 1-B in test condition 8 due to pump seal problems.
Failure of Pump 1-B seal required modification of test conditions 11 through 15 (Table 2.4-2).
To circumvent the use of Pump 1-B, test conditions 9 and 10, which called for four-pump operation at 500*F, were deleted. Upon reaching the 564*F plateau, the 2 and 3 pump, conditions 11,12 and 14 were then completed. Test condition 13 was schedule to be tested, as it was the sequential step between 12 and
- 14. However, due to a site power failure after obtaining data for condition 12, this sequence was no longer obtainable and as a result condition 13 was deleted. Pump 1-B was temporarily repaired and the four-pump (condition 15) 564*F data was then obtained.
2-3
2.5 DATA REDUCTION Data was reduced on-line to determine if the response was within the acceptance limits (Table 1.3-1).
This reduction included calcula-tion of the RMS values for both the response and forcing function instrumentation.
In addition, a spectrum analyzer was used to examine the spectral characteristics of selected instruments.
Of the 47 instrument channels used to acquire test data,19 failed during the CVAP data acquisition. An instrument history is shown in Table 2.5-1.
Because of instrument redundancy, the data acquired for the CVAP was sufficient to determine the dynamic response of the instrumented assemblies.
2.5.1 Core Support Barrel Response The motion of the CSB is primarily due to turbulent flow in the downcomer and acoustic pressure pulsations emitted by the circulat-ing pumps.
Table 2.5-2 presents the recorded on-line values for the critical strain gages and accelerometers.
The results show that the displacement obtained by the accelero-meters are all below the acceptance criteria of 30 mils. The measured strains are all below the acceptance lavel of 320 ME*.
The maximumE 3 ME, at test condition 14 (2 pumps,1 steam generator),
corresponds to an RMS stress level of approximately[ j psi, well
'below the acceptance limit of 8,500 psi.
Additional information was obtained from the on-line spectrum analyzer. It was observed that expected acoustic pressure pulsa-tions occurred _at multiples of the pump rotor and blade passing frequencies, 20 hz and 120 hz. Maximum values occurred at the first harmonic of the blade passing frequency of 240 bz.
- ME microstrain 2-4
A peak in the accelerometers att 3 hz was evident. Preliminary indications point to this as possibly being the CSB beam mode frequency predicted to be( ) bz.
Based on these observations the CSB motion is within acceptable response levels.
2.5.2 1.ower Support Structure Response The LSS experiences predominantly turbulent loading. Because its location close to the flow skirt, Tube No. 58 is subjected to the highest level of turbulence present in the LSS region.
Table 2.5-3 shows the on-line data for the instruments used to monitor the LSS. The measured values represent absolute values of the lower support structure displacement. When adjusted for motion of the core support barrel the test acceptance criteria was not exceeded. The strain. gauges indicates RMS strain levels ofC3ME corresponding to RMS stress values of aboutC J psi. Based on accelerometer data the maximum RMS stress of t 'Jpsi occurs at test condition 3 while for normal operation (test condition 15) the RMS stress ist. 3 psi. From this preliminary data, it can be concluded that no excessive vibration of the LSS occurred during the CVAP tests.
2.5.3 Upper Guide Structure Response Based on evaluation of' the hydraulic flow test data and the System 80 tube bank vibration analysis, it was concluded that tubes direct-ly in front of the outlet nozzles will be subjected to the maximum hydraulic loading due to cross flow.
Six tubes were selected for instrumentation. The locations of transducers are shown in Figures 2.2-6 and 2.2-7.
2-5
=__
e Table 2.5-4 gives the measured on-line data. The strain levels are well below the test acceptance criteria of 320 ME. Measured dis-placements represent the absolute motion of the upper guide struc-ture. When adjusted to reflect motion of the upper guide structure cylinder all values were within the acceptance limits.
i The highest recorded strain occurred on tube number six at test condition 15. This RMS strain of C 3 ME corresponds to an RMS stress of aboutC 3 psi, compared to the acceptance limit of 8,500 psi.
The UGS accelerometers had a failure rate of 50 percent.
However sufficient instrumentation remained with which to evaluate the response.
It is suspected that this was due to a loose conduit in the UGS region found during post test inspection after completion of the data acquisition. Some accelerometers which were noted as failed at test condition number 15 appear to have failed upon reaching test condition 11 (565'F plateau).
Based on this preliminary evaluation it can be concluded that the dynamic response of the UGS is within acceptable limits.
i 2.6 SIM4ARY Review of the on-line RMS values of strain (Table 2.5-2, 2.5-3, 2.5-4) indicate that all values are within the acceptance limits.
Displacements, when adjusted in the case of the LSS and UGS to reflect relative motion of the structure are also within acceptance limits. Stresses corresponding to these values are less than 500 psi compared to the acceptance criteria value of 8,500 psi. A summary of measured and predicted stress values, based on this preliminary evaluation are listed in Table 2.6-1.
Predicted values, at both the design and CVAP conditions, are conservative compared to l
measured values.
l l
l 2-6 l
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TABLE 2.2-1 CVAP INSTRUMENTATION ID L
Assembly Type No. Channels Location (Fig. 2.2-1)
Core Support
- 1. Pressure Transducer P1 1
CSB 120' Inlet Barrel
- 2. Pressure Transducer P2 1
CSB 300* Inlet (Fig. 2.2-3
- 3. Pressure Transducer P3 1
CSB 300* Level 7 2.2-4)
- 4. Pressure Transducer P4 1
CSB 300* Level 4
- 5. Pressure Transducer PS 1
CSB 270* Level 4
- 6. Pressure Transducer P6 1
CSB 270* Level 4
- 7. Pressure Transducer P7 1
CSB 300* Level 5
- 8. Pressure Transducer P8 1
CSB 300* Level 6
- 9. Pressure Transducer P9 1
CSB 240' Inlet
- 10. Strain Gage S1 1
CSB 180* Key Way
- 11. Strain Gage S2 1
- 12. S+. rain Gage 53 1
CSB 270* Key Way
- 13. Strain Gage S4 1
- 14. Strain Gage S5 1
CSB 180* Level 4
- 15. Strain Gage S6 1
- 16. Strain Gage S7 1
CSB 270* Level 4
- 17. Strain Gage S8 1
- 18. Biaxial Accelerometer Al 2
CSB 180 Snubber
- 19. Displacement Trans-ducer A2 1
CSB O' Snubber
- 20. Displacement Trans-ducer A3 1
CSB 120* Sn~ubber
- 21. Displacement Trans-ducer A4 1
CSB 240* Snubber Upper Guide
- 22. Pressure Transducer P10 1
UGS 180*-270* Tube 3 t
Structure
- 23. Pressure Transducer P11 1
UGS 180*-270* Tube 6 (Fig. 2.2-6
- 38. Pressure Transducer P13 1
UGS Plate 2.2-7) 24. Strain Gage 59 1
UGS 180*-270* Tube 6
- 25. Strain Gage S10' 1
- 26. Strain Gage S11 1
UGS 0*-90* Tube 3
- 27. Strain Gage S12 1
- 28. Biaxial Accelerometer AS 2
UGS 180*-270* Tube 3
- 29. Biaxial Accelerometer A6 2
UGS 180*-270* Tube 4
- 30. Biaxial Accelerometer A7 2
UGS 180*-270* Tube 6
- 31. Biaxial Accelerometer A8 2
UGS 100*-270* Tube 10
- 32. Biaxial Accelerometer A9 2
UGS 180*-270* Tebe 37
- 33. Triaxial Accelerometer A10 3
UGS 180*-270* Tube 187 Lower Sup-
- 34. Pressure Transducer P12 1
LSS Ins. Guide Tube 58 port
- 35. Strain Gage S13 1
LSS Ins. Guide Tube 58 Structure
- 36. Strain Gage S14 1
(Fig.2.2-5) 37. Biaxial Accelerometer All 2
LSS ICI Support Plate l
Totals 38 47 2-7 l
TABLE 2.4-1 ORIGINAL TEST CONDITIONS SEQUENCE RCP N M ER TEMPERATURE 1A 18 2A 2B TEST 1
Purg Start
<200*F S
NO NO NO T
2 Pump Start 200*F 0
NO S
NO T
3 Pump Start 200*F 0
S 0
NO T
4 Pump Shutdown 260*F 0
SP 0
NO T
5 Hot Shutdown 260*F 0
NO O
NO SS 6
Hot Shutdown 260*F 0
5, O
NO SS 7
Part Loop 500*F 0
SP 0
NO SS 8
Part Loop 500*F 0
5 0
NO SS 9
Pump Start 500*F 0
0 0
S T
10 Max Flow 500*F 0
0 0
0 SS 11 Hot Standby 564*F 0
0 0
0 SS 12 Pump Shutdown 564*F 0
0 0
SP T
13 Part Loop 564*F 0
0 0
NO SS 14 Part Loop 564*F 0
SP 0
NO SS 15 Part Loop 564*F 0
S SP NO SS KEY: NO - Not Operating 0 - Operating 1B 2A
[
S - Start SP - Stop SG1 0
80~ SG2 SS - Steady State T - Transient 1A 2B
- All test conditions are PRE-CORE.
2-8
TABLE 2.4-2 SUMARY OF TEST CONDITIONS SEQUENCE RCP NUMBER TEMPERATURE 1A 18 2A 2B TEST COMENTS 1
Pump Start
<200*F S
NO NO NO T
2 Pump Start 200*F 0
NO S
NO T
3 Pump Start 200*F 0
S 0
NO T
4 Pump Shutdwn 260"F 0
SP O
NO T
5 Hot Shutdown 260*F 0
NO O
NO SS 6
Hot Shutdown 260*F 0
S 0
NO SS 7
Part Loop 500*F 0
SP 0
NO SS 8
Part Loop 500*F 0
NO O
S SS 9
Pump Start 500*F T
Deleted 10 Max Flow 500*F SS Deleted
^
11 Part Loop 554*F 0
NO O
O SS 12 Pump Shutdown 564*F 0
NO O
NO O
S T
Deleted
- 14 Part Loop 564*F SP NO O
O SS 15 Hot Standby 564*F S
S 0
0 SS KEY: NO - Not Operating 0 - Operating 1B 2A S - Start SP - Stop SG1 0
80*
SG2 i SS - Steady State N
T - Transient 1A 2B
- All test conditions are PRE-CORE.
+ Pumps operated but no data recorded.
2-9
1 TABLE 2.5-1 CVAP TRANSDUCER HISTORY Acceleromef ers location Status AIX CS8 180* Snubber OK A1Y CS8 180* Snubber OK A2 CS8 0* Snubber Failed prior test start.
A3 CS8 120' Snubber OK A4 CSB 240' Snubber Failed 9 500*F A5X USS Tube #3 OK A5Y USS Tube #3 OK A6X USS Tube #4 Failed 9 564*F A6Y USS Tube #4 Failed 9 564*F A7X UGS Tube #6 Failed 9 564*F A7Y USS Tube #6 OK UGS Tube #10 Failed 9 564*F A8X A8Y
.UGS Tube #10 Failed 9 564*F A9X UGS Tube #37 Failet 9 564*F A9Y UGS Tube #37 Failed 9 564*F A10X UGS Tube #187 OK A10Y USS Tube #187 OK A10Z UGS Tube #187 OK A11X LSS Support Pit OK A11Y LSS Support Pit OK l
2-10
,--,---.,,,,,,n.,
TABLE 2.5-1 CVAP TRANSDUCER HISTORY (Cont'd.)
Pressure Trar.sducers Location Status P1 CSB 120' Inlet
- Failed 9 564*F P2 CSB 300* Inlet OK P3 CS8 300* LEY 7 Failed 9 564*F P4 CS8 300* LEY 4 OK PS CS8 292* LEV 4 OK P6 CS8 270* LEV 4 Failed 9 500*F P7 CSB 300* LEV 5 OK P8 CS8 300* LEV 6 OK P9 CSB 240' Inlet OK P10 UGS Tube #3 Failed 9 500*F Pil UGS Tube #6 Failed 9 564*F P12 LSS Tube #58 Failed 9 564*F P13 UGS Plate OK Strain 51 CSB 180* Keyway OK S2 CS8 180* Keyway OK S3 CSB 270* Keyway OK S4 CSB 270* Keyway Failed at Program Start S5 CS8 180* LEV 4 OK 56 CSB 180* LEV 4 OK S7 CSB 270* LEV 4 OK j
j S8 CSB 270* LEV 4 Failed at 500*F l
59 UGS Tube #6 OK S10 UGS Tube #6 Failed at 500*F S11 UGS Tube #6*
OK S12 UGS Tube #6*
OK S14 LSS Tube #58 Failed @ 500 F O' outlet nozzle (SG1); all others are 180* outlet nozzle (SG2).
2-11 9 14
TABLE 2.5-2 PRELIMINAltY C$a pratamwn CVAP DATA l
III CHANNEL INSTRUMENT ACCEPTANCE Test Conditions NO.
ID LEVEL 1
2 3
4 5
6 7
8 9
10 11 12 13 14 15
=
III
'~
30 MILS 1
Al-T 2
Al-R 30 MILS l
24 A2 30 MILS 25 A3 30 MILS 26 A4 30 MILS 39 51 320 ME(2) 40 52 320 ME(2) 7 41 S3 320 ME(2)
N 42 54 320 ME(2) 43 55 N/A 44 56 N/A 45 57 N/A l
46 58 N/A (11 See Table 2.2-1 and Figures 2.2-1 and 2.2-2 T = Tangential Direction R = Radial Direction V *-Vertical Direction
-6 In./in.
(2) ME = Hicro Strain = 10 (3) Table 2.4-2
^
TABLE 2.5-3 PRELIMINARY LSS MEASUIIED CVAP DATA OlANNEL INSTRitlENT ACCEPTANCE Test Conditions %I I
NO.
10 LEVEL 1
2 3
4 5
6 7
8 9
10 11 12 13 14 15
~
g gy.y(1) 33 gitS(2) 2 Al-R 11 MILS (2) 16 All-T 11 MILS (2) 17 All-R 11 MILS (2)
I3I 51 513 320 ME I3I 52 514 320 ME ro 8,
(1) Sse Table 2.2
- and Figure 2.2-3 LJ 1
i = Tangential Direction i
R = Jadial Direction (2) ine maximum dif ference of CS8 accelerometers Al-T and Al-R and LSS accelerometers All-T and All-R must be less than 11 mills, f.e.,
relative motion of LSS with respect to CSB is ilmited.
-6 in./in.
(3) ME = Micro Strain = 10 (4) Test Condition, See Table 2.4-2 i
.i 1
i
TABLE 2.5-4 PilELIMIMARY UCS DEASUIED CWAP DATA I
CHAMNEL IMSTituMENT ACCEPTAMCE Toat Conditfons *I Mo.
ID LEVEL 1
2 3
4 5
6 7
8 S
10 11 12 13 14 15 r
III 18.5 MILS (2) 3 A5-T 4
A5-R 16.5 MILS (2) 5 AG-T 18.5 MILS (2) 6 A6-R 18.5 MILS (2) 7 A7-T 18.5 MILS (2)
A A7-R 18.5 MILS (2) 9 A8-T 18.5 MILS (2) 10 A8-R 18.5 MILS (2) 11 A9-T 18.5 MILS (2)
Y 12 A9-R 18.5 MILS (2) 13 A10-T 18.5 MILS (2) 14 A10-R 18.5 MILS (2) 15 A10-V N/A I3I 47 59 320 ME I3I 48 510 320 ME I3I 49 511 320 ME III 50 512 320 ME l
(1) See Table 2.2-1 and Figures 2.2-4 and 2.2-5.
l T = Tangential Direction R = Radial Direction V = Vertical Direction (2) This test acceptance level was based on the UGS being rigid, however the accelerometers are measuring both the motion of the UGS.
and tube bank.
(3) ME = Micro Strain = 10'0 I"'!I"*
(4) Test Condition, See Table 2.4-2
. TABLE 2.6-1 DESIGN, CVAP, AND MEASURED VALUES OF PEAK STRESSES Peak Alternating Stress (psi)
Calculated Measured Component Location Design CVAP Normal Op*
Maximum **
4 i
4 l
CSB Upper I) l Flange "L
LSS ICI Nozzle UGS CEA Shroud l
Tubes
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- Maximum measured at (test condition)
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2-21
FIGURE 2.3-1 PALO VERDE DATA ACQUISITION SYSTEM l
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3.0 INSPECTION PROGRAM
3.1 INTRODUCTION
In accordance with the Reference 5 and 6 procedures, the visual inspection of the reactor internals and vessel interfaces of Arizona Nuclear Power Plant Unit I was completed with photographic document-ation.
The inspection was conducted in two phases.
The first phase (base-line inspection) was completed in May, 1982. The second phase (post hot functional pre-core inspection) was completed on August 2, 1983, after completion on July 8, 1983 of cold hydro and pre-core hot functional testing.
The purpose of the baseline inspection was to establish a record of internals surface conditions which could be compared with conditions after hot functional testing. This comparison, in conjunction with the results of the response measurements, provides a basis for verifying the structural integrity of the reactor internals subject-ed to flow-induced vibration prior to comercial operation.
This section includes a description of the conditions observed and coments on changes from the baseline inspection.
The inspections were performed and quality assured by qualified inspectors.
The locations inspected are shown in Figures 3.1-1 and 3.1-2.
3.2 DISCUSSION The following notes apply to the components and interface surfaces discussed below.
1.
Left and right orientation is always from the. reactor vessel centerline (0* to 180*).
3-1
2.
Discoloration observed and reported throughout the procedure is due to residue in the coolant depositing and staining the j
surfaces.
In some areas (such as alignment keys), the coolant flow direction is noticeable by variation in staining and residue build-up.
In general, throughout the internals, light staining and residue build-up occurs in areas of high flow while heavier residue deposits occur in areas of low flow and stagnation.
3.3 INSPECTION 3.3.1 Reactor Vessel - Core Support Barrel Interfaces 1.
Alignment Key Bottom Surfaces and Vessel Key 7, lots.
Alignment contact was noted on,the right side of all keys.
This would indicate that the Core Support Barrel (CSB) was installed towards the 225' position relative to the vessel during assemb-ly.
2.
Core Barrel Flange to Vessel Seating Surface. The vessel seating surface had indications of unifonn contact predominant-ly on a series of bearing bands all around the flange.
The CSB displayed the same bearing bands.
No wear was indicated, nor was there any evidence of abnormal motion of the flange and vessel ledge. The bands appear as high points burnished as radial differential thermal growth took place between the carbon steel vessel and the stainless steel CSB flange.
3.
Core Barrel to Reactor Vessel Outlet Nozzles. No contact was noted at these interface surfaces. A series of gauges, dings and scratches were found on all the nozzle surfaces.
4.
Core Barrel and Vessel Snubbers.
Full contact was noted at the 0* left face, 60* right face,120* left and right faces,180*
1 eft face, and 300* left and right faces.
Thse contact areas all appear normal with discoloration and some light burnishing.
3-2
5.
Core Barrel Circumferential Welds.
These welds showed no change from the baseline inspection except discoloration.
The welds all appeared sound and as manufactured.
6.
Reactor Vessel Flow Skirt. The flow skirt showed no change from the baseline inspection except for discoloration.
The welds all appeared sound and as manufactured.
Several pieces of the pump impellers, one thermal sleeve and several RTD's were found lodged between the flow skirt and the vessal.
No damage to either skirt or vessel was found. A series of small dings was seen on the CSB areas across from the vessel inlet nozzles where the loose parts entered the vessel.
3.3.2 Reacter Vessel Head - Internals Interfaces 1.
Upper Guide Structure Flange to Head Seating Surface.
The head and UGS flange had indications of unifom contact around the circumference. The contact was in the form of a series of bearing bands, containing radial scratches.
These scratches are attributed to differential themal expansion.
2.
Alignment Key to Surface and Vessel Head Key Slot.
Contact was noted on both sides of the head key slots. The contact areas all appeared nomal with discoloration.
3.3.3 Holddown Ring Contact With CSB and UGS The ring made continuous bearing contact with the CSB and UGS as.
noted by a circumferential band.
Superimposed on this band are radial scratches.
These scratches are attributed to differential themal expansion and in part to the rolling action of the ring as the head is bolted down. Measurements of the core barrel flange, holddown ring and UGS flange (Fig. 3.3-1) indicated that the ring would exert the required holddown force.
3-3
3.3.4 Core Barrel Interior 1.
Guide Lug Inserts to UGS Alignment Plate Slot Interfaces.
Contact was noted on both sides of the four guide lug inserts and slots. These contact areas all appeared normal with discoloration and some light burnishing.
2.
Inside the Core Shroud. The core shroud joints all appear as manufactured. A sampling of fuel assembly locating pins on the core support plate were found to be tight and unchanged from baseline inspection.
3.3.5 Lower Support Structure All components, welds, supports and nozzles appeared secure and as noted in the baseline except for overall discoloration.
3.3.6 Upper Guide Structure 1.
Tube Sheet.
All tubes, plates and welds appeared secure and as manufactured.
2.
Alignment Keys to UGS Key Slots.
Light contact was noted on most of the UGS key slot areas. The contact areas appeared normal with discoloration.
3.
CEA Shroud Assembly (Figure 3.3-2).
Seven CEA shrouds were found to contain cracks. All the cracks were near the heat affected zone of the extension shaft guide cuter plate welds (Fig. 3.3-1, number 1-7).
Non-destructive examination of the UGS Shroud Assembly, done after removal of the UGS assembly from the reactor, revealed cracks in seven web locations near the top of the assembly, cracks in four more CEA shrouds, and in two locations near the 3-4
bottom of the assembly.
In addition, wear marks were found on one CEA shroud tube on a corner if the assembly. These are identified in Figures 3.3-3, 3.3-4, as numbers 8-17.
4.
UGS Circumferential Welds.
These welds showed no change from the baseline inspection except discoloration.
The welds all appeared sound and as manufactured.
3.3.7 CVAP Instrumentation 1.
CSB and LSS Instrumentation. All instrumentation, welds and supports appeared secure and as assembled.
2.
UGS Instrumentation. Three Spring Mount Assemblies were loose when the locking pins vibrated off the assemblies. One of the assemblies broke in half, releasing the Belleville springs, spring housing, washer and upper shaft. The Belleville springs along with the upper shaft were found in a steam generator.
The other loose parts were found on the UGS Support Plate.
3.4 SUtWARY A comparison of the baseline Reactor Vessel / Internals interface surfaces with those of the post hot functional indicate that except for the conditions noted below. the internals performed as expected.
1.
Reactor Vessel (RV) Snubbers. The two socket head cap screw retaining pins on the right hand side of the 180* snubber were missing.
2.
CEA Shrouds.
Eleven CEA shrouds were found to contain thirteen cracks near the extension shaft guide outer plate welds.
Cracks were also found in seven locations in the webs connect-ing the shroud tubes, five near the top of the assembly and two near the bottom.
3-5
I 3.
Upper Guide Structure (UGS) CVAP Instrumentation.
Three Tube Spring Mount Assemblies became loose when the locking pins vibrated off the assemblies. The Belleville spring washers from the one of these assemblies were found in the steam generator.
In addition to these adverse conditions, there were indications of normal amounts of relative thermal growth between the stainless steel internals and the carbon steel vessel.
In areas where contact occurred between core support barrel (CSB) snubbers, guide lugs, and alignment keys, little or no wear was observed, but close fits were evident by discoloration and some surface burnishing.
Cor, tact between the reactor vessel, UGS flange, CSB flange, and closure head appeared uniform with no wear. The girth welds on the CSB and UGS all appeared sound as did the core shroud welds.
3.5 REACTOR COOLANT SYSTEM AND REACTOR COOLANT PUMP COMPONENT FAILURES Following the completion of pre-core hot functional testing Reactor Coolant Pump (RCP) LA was disassembled to perform a planned repair.
This inspection was not part of the CVAP program.
Upon inspection it was noted that several bolts that hold the diffuser ring and other bolts that hold the internal suction pipe onto the diffuser were missing or loose. Upon disassembly of the IB RCP, it was noted that the impeller had a portion of one of the vanes missing.
Further investigation revealed damage in the remaining RCP's and the reactor coolant system.
The results of examination of the UGS Shroud assembly, reactor coolant pumps and reactor coolant system has been reported to the NRC in Reference 7.
/
3-6
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SUMMARY
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4.0
SUMMARY
AND CONCLUSIONS Pre-core hot functional testing of Pala Verde Unit I was started in May, 1983 and completed in July, 1983. Over twelve hundred hours of operation, representing a minimum of ( ) cycles *, were accumulated by the -
support structures (Core support barrel, lower support structure and upper guide structure) prior to post test visual inspection.
Measurements were completed during these tests under a variety of conditions of flow (pump number and combinations) and temperature.
Preliminary evaluation of these data indicated that all measured stresses were within the acceptance limits.
Inspection of the core support assemblies before and after comple-tion of pre-core hot functional testing showed no unusual signs of contact or wear. However, inspection of the CEA. shroud assembly revealed cracks in heat affected weld zones in thirteen locations and eleven of the extension shaft guides and seven connecting web locations. The cause of these cracks is under investigation.
In addition conduit in the CEA shroud containing a portion of the CVAP instrumentation was found to have come loose. Thi: may hcve con-tributed to the failure of a portion of the instrumentation located in the UGS tube bank region.
During post test disassembly of the reactor coolant pumps it was discovered that portions of the impeller blades had failed near the l
tips and bolts holding the diffuser had become loose or had failed.
Parts of these failed pieces were found in the lower head area of l
the reactor vessel.
Based on the in water, beam mode, frequency of the core support barrel of I
C 3 Hertz.
1 4-1
Preliminary evaluation of data on pressure variations within the reactor (Appendix A) concluded that both random and periodic pres-sure variations were in agreement with the values used in analyzing the dynamic response of the internals.
Furthermore, these spectra indicated no unusual characteristics that could have been judged as being caused by the.. pump blade failures.
~
Based on this preliminary evaluation it can be concluded that the dynamic response of the three core support structures instrumented
~
for the CVAP (Core support barrel, lower support structure and upper guide structure) is acceptable for long term operation of the reactor.
However, design modifications to both the CEA shroud package and the reactor coolant pumps are scheduled for additional test in Unit 1 in tarly 1984 (Ref. 7).
2 5
4-2
References:
(1) Regulatory Guide 1.20, Rev. 2, " Comprehensive Vibration Assessment Program for Reactor Internals During Preopera-tional and Initial Startup lesting."
(2)
"A Comprehensive Vibration Assessment Program for the Prototype System 80 Reactor Internals Palo Verde Nuclear Generating Station Unit 1," CEN-202-(V)-P.
(3) ASME Boiler and Pressure Vessel Code,Section III,1977.
(4) "Palo Verde Unit 1 Hot Functional Test Procedure".
(5) Comprehensive Vibration As:essment Program Project Proce-dure for Visual Inspection of Reactor Yessel Internals for Arizona Nuclear Power Plant Unit #1.
(6) Comprehensive Vibration Assessment Program Standard Procedure for Visual Inspection of Reactor Vessel Inter-nals for SYS80 Type Plants.
l (7)
Interim Report - E. E. Van Brunt (APS) to USNRC (Region 5)
NAPP-27598, August 19, 1983.
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l 4-3 i
APPENDIX A 1
l PRELIMINARY EVALUATION OF PREDICTED VERSU$ MEASURED PRESSURES.
Dynamic response of the three assemblies considered in this program is due to hydraulic loads. The analysis assumes that these hydraulic forces can be separated into deterministic (periodic) and random components.
The periodic loads of interest are those caused by pump induced pressure variations. These variations in pressure are acoustic in nature, occurring at hannonics of the pump rotor and blade passing frequencies, independent of flow rate. Generally random loads are primarily due to turbulence. The magnitude of these turbulent fluctuations related pressure are normally proportional to the kinetic head of the flow (one-half the density times the velocity squared) and occur over a broad range of frequencies. Flow measurements results, taken during four pump operation, indicate the flow rate to be within 1% of the flow rate assumed in the analytical predictions.
Analyses for the dynamic response of the nsemblies utilized a variety of methods to determine the magnitudes and frequencies for these forces, both analytical and empirical, (Ref. 2).
A preliminary evaluation of the data obtained from pressure transducers at various locations during CVAP testing was done to determine if these data contain indications of differences between expected and measured data that are possibly related to reactor coolant pump (RCP) impeller. blade failures.
Data from transducers pressure P2, at the 300* (RCP1A) inlet nozzle location on the CSB, P12, on Instrument nozzle 58 on the LSS and P13, on the bottom plate of the UGS cylinder were reduced for the following cor.ditions of flow and temperature:
Test Test Condition Temperature Pumps 1A 18 2A cB 6
Hot Shutdown 260*
0 S
0 NO 11 Part Loop 564*
0 NO O
O 15 Hot Standby 564*
S S
0 0
The reduced data are shown in Figures A-1 to A-9.
A-1
Based on these data; the following observations can be made.
1.
Periodic pressure pulsations occur, as expected, at multiples of the blade passing frequency; e.g., 120, 240, 360 and 480 hertz.
I i
2.
Per the predictions in Ref. 2, the largest values of periodic pressures l
occur at 240 hertz. A comparison shows fair agreement between measured 4
l and predicted values (Table A-1) particularly at the 4 pump, 564*F condition for normal operation. '
3.
Measured periodic pressures at both the rotor harmonics and at the blade passing frequency (120 hz) are lower than those assumed in the analysis.
4.
The magnitude of the random spectra for the CSB and the LSS are lower than that assumed in the analysis and decreases with frequency in con-trast to the white noise spectrum assumed in the analysis (Figures A-1,
(
2,4,5,7,8).
5.
The spectra for P13, on the underside of the UGS bottom plate, decreases with increasing frequency similar to the spectra used in the analysis based on scale model tests for the tube bank (Figures A-3, 6, 9).
In conclusion, measured values of periodic and random pressure variations are either in agreement or lower than values used in computing dynamic response of the assemblies.
l A-2
TABLE A-1 COMPARIS0N OF PREDICTED AND MEASURED RMS PERIODIC PRESSURE AT 240 HERTZ Condition Transducer P2 P12 P13 Test Pumps Temp (*F)
Pred Meas Pred Meas Pred Meas 6
3 260 11 3
564 15 4
564 Note:
Response of the CEA shroud tubes was determined based on a scaling of the response of the tubes in the scale model tests. This in-cluded both periodic and random response. Thus no values of period-ic pressure were necessary for the analysis.
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l A-3
FIGURE A-1 POWER SPECTRAL DENSITY 100 PALO VERDE 1 PVMP 6 262/381 1 A, 1B,2A P2 CSS 300 INLET PRELIMINARY 10*1 10 2 N
E N
k 4
10 l
104 i
104 O
50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-4
FIGURE A-2 POWER SPECTRAL DENSITY 10' i
PALO VERDE 1 PVMP 6 262/361 1 A, 1B,2A P12 LSS TUBE 58
~
PRELIMINARY 10'1.
10 2 4
g E
N k
10-3 l
l 4
10 l
l 10-5 _
i e
i i
i i
i i
i 0
50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-5
l FIGURE A-3 POWER SPECTRAL DENSITY 10'l i
a s
i s
a s
PALO VERDE 1 PVMP 6 262/361 1 A, 1B,2A P13 UGS PLATE PRELIMINARY 10 2 10 3 Y
~2 12 4
10 10-5 i_
]
I I I
10-6 O
50 100 150 200 250 300 350 400 450 50 FREQUENCY,HZ A-6
--s-s y
n,.e n-_.-
,,.,e
,-g-,,-,-e+
v---,.
FIGURE A-4 POWER SPECTRAL DENSITY 4
1x101 PALO VERDE 1 PVMP 11 565/2250 3-PUMP P2 CSB 300 INLET PRELIMINARY 0
1x10 1x10*1 N
E a
f 1x10~2 l
l 4
1x10
_i r
!!! ! I 9
l M
f I E
I*
a ee ta e
a aa m-a a
O 50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ l
I i
l A-7 l
1
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FIGURE A-5 POWER SPECTRAL DENSITY 1x109' PALO VERGE 1 PVMP 11 585/2250 3-PUMP P12 SS TUBE 5B PRELIMINARY 1x10'l 1x10 2 N
E ce k
4 1x10
~
t l
l 1x104-
/
~\\
Tx104 O
50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-8 l
FIGURE A-6 POWER SPECTRAL DENSITY 1x100 PALO VERDE 1 PVMP 11 566/2250 3-PUMP P13 UGS PLATE PRELIMINARY 1x10'l
~
~
1x10-2l 5
~"
I 1x104 D
1x10 1
h 1x104 0
50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-9
1 FIGURE A7 POWER SPECTRAL DENSITY i
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I I
I I
I 5
5 5
I i
I I
PALOVERDE.1 PVMP 15. 56E/2250A, SPUMP P2' CSB 300 INLET PRELIMINARY 1
p 10*1 l
l t
10-2 N
E t
n_
ta.
A 4
10 t
l l
l
[
l 4
10 l_
10-5 i
t l
0 50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-10
FIGURE A-8 POWER SPECTRAL DENSITY 0
10 PALO VERDE 1 PVMP 15 565/2250
- 4. PUMP P12 SS TUBE 58 PRELIMINARY q
10-1 10-2 Nk n-104 4
10 i
i i
e i
1 i
10-5 j 0
50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-11
1 FIGURE A-9 POWER SPECTRAL DENSITY 0
1x10 1
i i
1 1
PALO VERDE 1 PVMP 15 565/2250 4-PUMP P13 UGS PLATE PRELIMINARY 1x10~1 1x10'2 N
?
Z m2 t
4 1x10 l
1x104
'I II II 'IU I
1x10'"
O 50 100 150 200 250 300 350 400 450 500 FREQUENCY,HZ A-12
COMBUSTION ENGINEERING, INC.
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