05000261/LER-2008-002, Regarding Manual Reactor Trip Due to High Turbine Vibrations
| ML090230170 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 01/15/2009 |
| From: | Kapopoulos E Progress Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RNP-RA/08-0118 LER 08-002-00 | |
| Download: ML090230170 (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 |
| 2612008002R00 - NRC Website | |
text
& Progress Energy Serial: RNP-RA/08-0118 JAN 1 5 2009 Attn: Document Control Desk United States Nuclear Regulatory Commission Washington, DC 20555-0001 H. B. ROBINSON STEAM ELECTRIC PLANT, UNIT NO. 2 DOCKET NO. 50-261/LICENSE NO. DPR-23 LICENSEE EVENT REPORT NO. 2008-002-00 REACTOR TRIP DUE TO HIGH TURBINE VIBRATION Ladies and Gentlemen:
The attached Licensee Event Report is submitted in accordance with the requirements of 10 CFR 50.73. Should you have any questions regarding this matter, please contact Mr. C. A. Castell at (843) 857-1626.
Sincerely, Ernest J. Kapopoulos, Jr.
Plant General Manager H. B. Robinson Steam Electric Plant, Unit No. 2 CAC/ahv Attachment c:
L.A. Reyes, NRC, Region II M. G. Vaaler, NRC, NRR NRC Resident Inspector Progress Energy Carolinas, Inc.
Robinson Nuclear Plant 3581 West Entrance Road Hartsville, SC 29550
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES 08/31/2010 (9-2007)
Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and LICENSEE EVENT REPORT (LER) fed back to industry.
Send comments regarding burden estimate to the Records and FOIA/Privacy Service Branch (T-5 F52), U.S. Nuclear Regulatory Commission, (See reverse for required number of Washington, DC 20555-0001, or by internet e-mail to infocollects@nrc.gov, and to digits/characters for each block) 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 I respond to, the information collection.
- 3. PAGE H. B. Robinson Steam Electric Plant, Unit No. 2 05000261 1 OF 3
- 4. TITLE Manual Reactor Trip due to High Turbine Vibrations
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED SFACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR 05000 NUMBER NO MONTH DAY YEAR 05000 FACILITY NAME DOCKET NUMBER 11 17 2008 2008-002 00 01 16 2009 05000
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
- 9. OPERATING MODE El 20.2201(b)
El 20.2203(a)(3)(i)
[]
50.73(a)(2)(i)(C)
E] 50.73(a)(2)(vii)
El 20.2201(d)
El 20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
E] 50.73(a)(2)(viii)(A)
E]
20.2203(a)(1)
El 20.2203(a)(4)
E]
50.73(a)(2)(ii)(B)
[]
50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 0l 50.36(c)(1)(i)(A)
[I 50.73(a)(2)(iii)
C]
50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 20.2203(a)(2)(ii)
El 50.36(c)(1)(ii)(A)
Z 50.73(a)(2)(iv)(A)
[j 50.73(a)(2)(x)
El 20.2203(a)(2)(iii)
El 50.36(c)(2)
[E 50.73(a)(2)(v)(A)
El 73.71(a)(4) 78%
El 20.2203(a)(2)(iv)
E]
50.46(a)(3)(ii)
[j 50.73(a)(2)(v)(B)
El 73.71(a)(5)
El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
E] 50.73(a)(2)(v)(C)
El OTHER Specify in Abstract below or 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D) in Additionally, a new procedure, CM-042, "Generator Maintenance and Inspection," was used to install the refurbished and machined generator hydrogen seals during RO-25.
This procedure did not provide independent verification or a QC hold point for the critical dimensions.
The lack of verification performed on these tight clearances is the most probable cause of the generator hydrogen seal rub.
The soft foot condition can be attributed to incorrect positioning of shim material.
IV.
CORRECTIVE ACTIONS
Completed Corrective Actions:
- Gusset plates were added to provide more stability.
- Generator Hydrogen seal was replaced and critical dimensions verified.
- 15 inch shims were installed and were placed in different locations.
- Night Order 08-17 was issued on December 3, 2008, stating, "If turbine vibrations exceed 10 mils, a normal plant shutdown should be commenced in accordance with GP-006 [Normal Plant Shutdown From Power Operation To Hot Shutdown]."
- Abnormal Operating Procedure, AOP-006, was revised to improve operator guidance for determining the need to trip the reactor, reduce the likelihood of reactor trips due to turbine vibrations, and has also been modified to add actions for operators to reduce turbine vibrations.
Planned Corrective Actions
Procedures CM-042, "Generator Maintenance and Inspection," and CM-024, "Exciter Maintenance and Inspection," are scheduled to be revised by March 20, 2009, to strengthen the detail concerning shim installation and to provide independent verification or QC hold points for all critical dimensions.
V. ADDITIONAL INFORMATION
Previous Similar Events:
Recent LERs for HBRSEP, Unit No. 2, were reviewed.
There were no similar events identified.