05000389/LER-2008-001, RCP 2B1 Upper Seal Cavity Line Leak
| ML081080104 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 03/27/2008 |
| From: | Johnston G Florida Power & Light Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-2008-068 LER 08-001-00 | |
| Download: ML081080104 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3892008001R00 - NRC Website | |
text
0 FPL Florida Power & Light Company, 6501 S. Ocean Drive, Jensen Beach, FL 34957 March 27, 2008 L-2008-068 10 CFR 50.73 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Re:
St. Lucie Unit 2 Docket No. 50-389 Reportable Event: 2008-001-00 Date of Event: January 29, 2008 RCP 2B1 Upper Seal Cavity Line Leak The attached Licensee Event Report 2008-001-00 is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.
Site Vice Presi, St. Lucie Plant GLJ/dlc Attachment j1-e99 LLL an FPL Group company
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/201(
(9-2007)
Estimated burden per response to comply with this mandatory collection request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Records and FOIA/Privacy Service Branch (T-5 LICENSEE EVENT REPORT (LER)
F52), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not
_ required to respond to, the information collection.
- 3. PAGE St. Lucie Unit 2 05000389 1 OF 3
- 4. TITLE RCP 2B1 Upper Seal Cavity Line Leak
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SEUNILFACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR NUMBER NO.I FACILITY NAME DOCKET NUMBER 01 29 2008 2008-001 00 03 27 2008
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)
El 20.2201(b)
El 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii) 1 El 20.2201(d)
El 20.2203(a)(3)(ii)
Z] 50.73(a)(2)(ii)(A)
El 50.73(a)(2)(viii)(A)
El 20.2203(a)(1)
El 20.2203(a)(4)
El 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
[I 20.2203(a)(2)(i)
El 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
El 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL [I 20.2203(a)(2)(ii)
[: 50.36(c)(1)(ii)(A)
E) 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
El 20.2203(a)(2)(iii)
El 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71 (a)(4) 100%
[E 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71 (a)(5)
[I 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
El 50.73(a)(2)(v)(C)
El OTHER El 20.2203(a)(2)(vi)
Dl 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in
Corrective Actions
The corrective actions and supporting actions are entered into the site corrective action program.
Any changes to the proposed actions will be managed under the commitment management change program.
Completed Corrective Actions
Repaired cracked socket weld by replacing the controlled bleedoff as well as the upper and middle seal cavity piping spool pieces for all four RCPs with 2:1 taper socket welds.
Long Term Corrective Actions
- 1. Forensic metallurgical evaluations of selected socket weld fittings on RCP seal lines to address environmental issues.
- 2.
Establish long term RCP pump and coupling maintenance practices to reduce vibration.
- 3.
Actions to be performed on the Unit 1 RCP sensing lines during the upcoming refueling outage include: chemical analysis of water samples, replacement of the flanged spools connected to the pump seals consistent with Unit 2 criteria, utilization of 2:1 taper socket weld design or butt weld and flushing of certain lines to achieve normal levels (<50 ppb) of corrosive contaminants (chlorides, fluorides and sulfates) in each of the eight lines.
Similar Events
There have been (3) three similar failure events'at PSL Unit 2 involving cracked RCP seal lines: 1) Inside diameter initiated low stress high cycle fatigue of the 2B1 RCP lower seal injection line socket weld;
- 2) outside diameter initiated low stress high cycle fatigue of the 2B2 RCP seal injection vendor J groove weld; 3) inside diameter initiated environmental assisted cracking under cyclic loading.
While each of these events involved a different failure mechanism, vibration loading was a common key contributor.
A search of the INPO Operating Experience database, Industry Owner Groups, and other Utilities identified multiple plant events involving RCP seal injection line with cracked welds relating to vibration, environmental, water chemistry, and weld material, which each independently or collectively contributed to these types of events within the nuclear industry.
Failed Components RCP 2BI Upper Seal Cavity piping 3 inch schedule 160 304 SS piping socket weld at
- flange, SSION