05000302/LER-2005-004, Re Motor-Operated Main Feedwater Isolation Valve Inoperable Due to Motor Rotor Oxidation/Corrosion
| ML053550367 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 12/14/2005 |
| From: | Franke J Progress Energy Florida |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 3F1205-02 LER 05-004-00 | |
| Download: ML053550367 (8) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 3022005004R00 - NRC Website | |
text
Progress Energy Crystal River Nuclear Plant Docket No. 50-302 Operating Ucense No. DPR-72 Ref: 10 CFR 50.73 December 14, 2005 3F1205-02 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
Subject:
LICENSEE EVENT REPORT 50-302/2005-004-00
Dear Sir:
Please find enclosed Licensee Event Report (LER) 50-302/2005-004-00. The LER discusses a motor-operated Main Feedwater Isolation Valve being inoperable due to oxidation/corrosion of the motor rotor magnesium fans and shorting ring. This report is being submitted pursuant to 1 OCFR50.73(a)(2)(i)(B).
No new regulatory commitments are made in this letter.
If you have any questions regarding this submittal, please contact Mr. Paul Infanger, Supervisor, Licensing and Regulatory Programs at (352) 563-4796.
Sincerely, on Franke Plant General Manager Crystal River Nuclear Plant JAF/dwh Enclosure xc:
Regional Administrator, Region II Senior Resident Inspector NRR Project Manager Progress Energy Florida, Inc.
Crystal River Nuclear Plant 15760 W. Powerline Street Crystal River, FL 34428
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6r2004)
, the NRC digits/characters for each block) may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE CRYSTAL RIVER UNIT 3 05000302 1 OF 7
- 4. TITLE Motor-Operated Main Feedwater Isolation Valve Inoperable Due To Motor Rotor Oxidation/Corrosion
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILmES INVOLVED 1SEQUENTIALI REV FCLTNAEDOCKET NUMBER MONTH DAY YEAR YEAR NUMBER NO.
MONTH DAY YEAR N/A 05000 FACILITY NAME DOCKET NUMBER 28 2005 2005 - 004 - 00 12 14 2005 N/A 05000 9.NATING MlODE 1
i.THISREP ~tTISSUBMI~rEDPURSUAREOQUIREMENTS OF 10 CFR§: (Check allthat apply) o 20.2201(b) 0 20.2203(a)(3)(i) 0 50.73(a)(2)(i)(C) 0 50.73(a)(2)(vii) 1 0 20.2201(d) 0 20.2203(a)(3)(li) 0l 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viii)(A) o 20.2203(a)(1) 0 20.2203(a)(4) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(2)(viii)(B) o 20.2203(a)(2)(i) 0 50.36(c)(1)(i)(A) 0 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 0 20.2203(a)(2)(ii) 0 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x) ol 20.2203(a)(2)(iii) 0J 50.36(c)(2) 0 50.73(a)(2)(v)(A) 0 73.71 (a)(4) o ] 20.2203(a)(2)(iv) 0 50.46(a)(3)(ii) 0 50.73(a)(2)(v)(B) 0 73.71(a)(5) 51%
El 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(C) 0 OTHER o 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B) 0 50.73(a)(2)(v)(D)
Specify in Abstract below or in (If more space is required, use additional copies of NRC Fonn 366A)
EVENT DESCRIPTION
At 19:10, on October 28, 2005, Progress Energy Florida, Inc. (PEF), Crystal River Unit 3 (CR-3) was operating in MODE 1 (POWER OPERATION) at 51 percent RATED THERMAL POWER when the breaker for B Train motor-operated Main Feedwater Isolation Valve (MFIV) [SJ, ISV] FWV-29 motor [SJ, MO] tripped soon after the valve started cycling closed. This occurred during power reduction in preparation for a refueling outage. At the time, CR-3 was being shutdown in accordance with Operating Procedure OP-209A, "Refueling Outage Plant Shutdown and Cooldown."
The MFIVs for each Once Through Steam Generator (OTSG) [AB, SG] consist of the Main FW pump suction valve, the main/startup/low load block valves (in parallel) and the Main FW pump discharge cross-connect valve. FWV-29 is the B Train main block valve.
Improved Technical Specification (ITS) 3.7.3, "Main Feedwater Isolation Valves," requires two MFIVs in each FW System flow path to be operable with at least one MFIV capable of isolating FW within the required isolation time while in MODES 1, 2 and 3. With FWV-29 inoperable, the Required Actions of ITS 3.7.3 were entered for Condition A, "One or more MFW flow paths with one MFIV inoperable." Required Action A.1 requires that the affected flow path(s) be isolated within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Required Action A.2 requires that the affected flow path(s) be verified as isolated once per 7 days.
At 21:03, on October 28, 2005, FWV-29 was manually closed. This action isolated the affected MFW flow path and satisfied Required Action A.1 of ITS 3.7.3. At 15:59, on October 29, 2005, MODE 4 (HOT SHUTDOWN) was entered. This action made Required Action A.2 of ITS 3.7.3 no longer applicable.
The cause for failure of FWV-29 to automatically close was initially unknown. Therefore, FWV-29 was considered to have become inoperable when it failed. No 1 OCFR50.72 or 1 OCFR50.73 reportability criteria were determined to be applicable. Potential reportability was re-visited upon receipt of a failure report dated November 11, 2005, that was provided by an electric motor repair facility. That failure report supported a conclusion that FWV-29 became inoperable and would not have been able to perform its intended function for some unspecified period of time prior to the actual failure.
In order for this event to be determined not reportable, FWV-29 would have had to become inoperable on or after 19:10 on October 25, 2005. Based on engineering judgment, FWV-29 became inoperable at some point prior to that time. Therefore, FWV-29 is considered to have been inoperable for a period of time longer than the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed by ITS 3.7.3, Condition A, Required Action A.1. This condition is reportable under 10CFR50.73(a)(2)(i)(B).
(If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A)
ATTACHMENT 2 LIST OF COMMITMENTS The following table identifies those actions committed to by PEF in this document. Any other actions discussed in the submittal represent intended or planned actions by PEF. They are described for the NRC's information and are not regulatory commitments. Please notify the Supervisor, Licensing & Regulatory Programs, of any questions regarding this document or any associated regulatory commitments.
RESPONSE
COMMITMENT
DUE DATE SECTION No regulatory commitments are being made in this submittal.
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