ML050900056
| ML050900056 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 03/29/2005 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| References | |
| Download: ML050900056 (23) | |
Text
High Pressure Coolant Injection Pump Vibration Issue Wednesday, December 8, 2004 1:00 p.m. - 4:00 p.m.
U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike, Room 0-8B4 Rockville, Maryland Name Email Organization Gu1JEAJ)t~I? 6F-Z 98 (I Alk tA61~tk ri(v /1 JJItX~oaa4-JC:a W-?O li,-. oV NiAD-5 1-1PIIq z2 eo A PH/tpf4'v~Ž/ f~0 -~ ~etr~j&
Enclosure 1
Is M~MUR~Ine IF Pilgrim Nuclear Power Station December 8, 2004 Enclosure 2
HPC.I InmService Testing Pilgrim Nuclear Power Station December 8, 2004
Meeting Purpose l Summarize the basis for the Pilgrim request concerning HPCI IST vibration monitoring
. Answer Staff questions about the basis for Pilgrim's conclusions
Agenda
+ HPCI System Pump Configuration
+ HPCI System Safety Function
+ HPCI System IST Vibration Monitoring
+ HPCI System Vibration
- Code ReqUirements
- Vendor Recommendations
- Conclusion
HPCI Pump Configuration P8H 030062D3 Main Pump Booster Pump
-Z, HPCI PuMp Configuration
HPCI Pump Configuration
HP(C Function, Mission Time, and Operational Data
- Designed to pump water into the vessel in the event of a small break o Delivers 4250 GPM @ 1120 to 150 psig
- Mission time about 16 minutes for limiting break
- Operates intermittently during non-limiting small breaks.
@Back-up systems: ADS, Core Spray, LPCI, RCIC
, I,_ .:-I, .,. wv ! .- ,, .I...I............'.....-............................-....................... .. a.;s
, .. .c .S 0 . I _ ................................................................................................................................. ..
H'PCI Function, Mission Time, and Operational Data Equipment Qualification Profile time:
5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> o Pump speed decreases from rated as vessel depressurizes or operator controls flow
- Periodic Test (Surveillance) Duration:
1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />! quarter e Cumulative operation since plant start:
about 270 hours0.00313 days <br />0.075 hours <br />4.464286e-4 weeks <br />1.02735e-4 months <br /> X Periodic test demands are comparable to DBA requirements for operation at speed
HCI Pouu Vi b ration 0Monitoring Program GOH P8H GOV P8V.
GOA P3H P4H P7H P8H P3V P4V P7V P8V P3A P8A Other points are monitored as part of Vibration Monitoring for Preventive Maintenance and Balance
, i HPCI Data November 24, 2004 IST - IST. P205 kPCI 042.5k HFCI ISTR -pF3H Y3 BEARING-PUMP HORFZCVTAL
~ ~ RouleiS~eectrurn
- 1. .- 24-NOV-04 00:44:12 OVRALL& .8003 V-DG j PK . .7023 LOAD =4250.0 b: 0.8 flPM= 4012.
RPS = 66.07 i'
u 0.6 4x BOOSIER
'I' PUIP RPt.
0 0
.Ew PNPS Cazuliatiiun 1o 0.4 . 4. Delele DiscrtoW P&4k a 4x DO*ster Pump RPM:
(0.800)2 - (OA Levelf5
- (5.Gs2 _ 4x 1BP RPM Poikj'
. - SubIrao Sq Values SK btAIN I lo.198)"s - U.44 IrvSec OA x RPM ZX RPt.1 PUMPRPM 0.2 .7~ I I I oI. .
0 i 1 ii A -. .,- p4 Frequuricy in Order S 6 Orar Freq; Spuc:
2.017 134.88
.66.5
H CI Wata August 24, 2004 IST ISr. P205 HPCI 442.5k HPCI ISTl -P314 U3 13FARING-PU0.1P HORIZONTAL 0- r - -
Routa Spectrum 24-AUG.04 20:46:30 i OWRAL.L= .9415 V-DG PK - .9331 LOAD =4250.0 RPFI = 398D.
tl.l3 RPS - 66.3.
t i
i 4xcBOOSTER PUMP FRPU a
- t PNPS Ca!culation lo 04 Delolo Discrete Peak
@4x Boossw Punip RPM:
! 0,942f) = (OA Levele
- (0. 822)J = (OxBP RPM Peaki' Subtract Sq Values 5xt.IAIN (CI.212)" G 0,4a l/Sec OA Ix RPM7 2x PUMP RPM 0.2 2a017 U I 4 S a Fteq:
Frequeroy in Order Spec .822
HPCI Data May 259 994 fiX X2D3. P205 HPCI TURD & PUMP 1.0 ~. X203 HPCI *P3H 43 GLARIRING-OUte Spectrum 25-MAY94 0927:30 O'%MALL= .8515 'V-DG LOAD u4250.0 RPM- 400J.
RPU = fi.130 0.6_t 0.6 t. ;. '1~ 4x BOOSTER i FPUMP RPM 8
w PNPS Caalzulafion So Delete DiGcrotae Peak o Ic I a x Booster Pump RPM:
(0.852)" - (CA LevelD
- (0.710)f = (4x BP APRM Peak)j II
...... - Sibtract SC Valuos I 5x MAN i (0.222)J r 0.471 lnfStc OA ix RPMA 2x RPM I PUMP RPM '
A I I n.2 : i: I 0 oI , \ .11I Ii I t 2 34 Otdr z.01 s Fruq: 136.32 Frequenpry n Ctder Spuce .710
Code Requirements OMa-1 996, ISTB 4.0:
Reference Values are established by the program. Relative and
.'. 17, Absolute Values are provided in ISTB Table 5.2.1-1.
Code Requirements Note 1: ISTB 4.3 Reference Values, item (g) footnote for analysis:
""Vibrationmeasurements of pumps may be foundation, driver, and piping dependent.
Therefore, if the initial vibration readingsare high and have no obvious relationshipto the pump, then vibration measurements should be taken at the driver, at the foundation, and on the piping and analyzed to ensure that the reference vibration measurements are representativeof the pump and that the measured vibration will not prevent the pump from fulfilling its function.
Code Requirements Note 2:STB 4.6: New Reference Values:
"In cases where pump's test parametersare within either the alert or requiredaction ranges of Table ISTB 5.2. 1-1 Table ISTB 5.2.1-2, Table ISTB 5.2.2-1, or Table ISTB 5.2.3-1, and the pump' continued use at the changed values is supported by an analysis, a new set of reference values may be established.
This analysis shall include verification of the pump's operationalreadiness. The analysis shall include both a pump level and system level evaluation of operationalreadiness, the use of the change in pump performance, and an evaluation of all trends indicatedby the availabledata. The results of the test shall be documented in the record of the tests (see Article ISTB 7)."
Pilgrim Analysis Pump performance Analysis
- Analyzed source of vibration
- Vibration of concern is attributed to the Booster Pump and associated harmonics
- Displacement due to vibration is lower than clearance of bearings
- Vibration concern is only at rated speed. Pump operation time post accident is very short.
- Adequate monitoring for degradation can be accomplished with corrections for booster pump induced vibration
Pilgrim Analysis
- Pump performance Analysis (cont.)
- Corrected vibration data indicates HPCI Main Pump is below required action range No degradation of HPCI Pump performance will N
result from the vibration and the HPCI System will perform its design function o Vendor Technical Notes were considered in the analysis a Vibration trending has shown no degradation e Intent of code requirements are met
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X In. S; v .4.....
Vendor Recommendations for Reducing Vibration Verify correct dynamic alignment of all shaft couplings Completed Verify acoustic resonant condition from measured flow, RPM, water temperature, and vibration frequency Completed
Wendorw Recoqmmendations for Reducing Vibration The Tech Note identified the following potential pump modifications (cont.):
Change the length of the interconnecting piping At Pilgrim this means shortening the cross over pipe. That is not practicable considering the as-built configuration
- Install an acoustic filter in the interconnecting pipe No proven design available. Not practicable considering safety related application
Vendor lRUP o endations for Reducing Vibration The Tech Note identified the following potential pump modifications (cont.):
Alter the mounted structural natural frequency of the injection pump Not practicable to significantly stiffen the structure
- Change the number of vanes in the booster pump impeller Most realistic of options. Costs approximately $487,000. Does not completely resolve issue. Will not improve system performance.
Conclusion Historical pump trend data has been evaluated and confirms that HPCI pump is operable and degradation has not been observed Proposed program using new Reference Values which take into consideration as-built pump configuration are within the scope of ISTB 4.6 and 6.2 and provides an alternative for monitoring pump performance
- Proposed program meets the intent of the code and provides an equivalent level of protection as the code
- The vendor identified modifications are Unwarranted and are an undue burden