05000220/LER-2009-002, High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations
| ML091670103 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/08/2009 |
| From: | Yoe J Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 09-002-00 | |
| Download: ML091670103 (7) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(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 10 CFR 50.73(a)(2)(iv)(B), System Actuation |
| 2202009002R00 - NRC Website | |
text
Jim Yoe Plant General Manager P.O. Box 63 Lycoming, New York 13093 315.349.5205 315.349.1321 Fax 0Constellation Energy
- - Nine Mile Point Nuclear Station, LLC June 8, 2009 U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 ATTENTION:
SUBJECT:
Document Control Desk Nine Mile Point Nuclear Station Unit No. 1; Docket No. 50-220 Licensee Event Report 2009-002, High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations Gentlemen:
In accordance with 10 CFR 50.73(a)(2)(iv)(A), please find attached. Licensee Event Report 2009-002, High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations.
There are no regulatory commitments in this submittal.
Should you have questions regarding 'the information in this submittal, please contact T. F. Syrell, Licensing Director, at (315) 349-5219.
Very truly yours, JMY/MHS
Attachment:
Licensee Event Report 2009-002, High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations cc:
S. J. Collins, NRC R. V. Guzman, NRC Resident Inspector, NRC t-4 I&K
ATTACHMENT LICENSEE EVENT REPORT 2009-002 HIGH PRESSURE COOLANT INJECTION SYSTEM INITIATION FOLLOWING A MANUAL TURBINE TRIP DUE TO HIGH TURBINE BEARING VIBRATIONS Nine Mile Point Nuclear Station, LLC June 8, 2009
ONRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010 (9-2007)
, the NRC may not conduct digits/characters for each block) or sponsor, and a person is not required to respond to, the information digis/carater foreac blck)collection.
- 3. PAGE Nine Mile Point Unit 1 05000220 1 OF 5
- 4. TITLE High Pressure Coolant Injection System Initiation Following a Manual Turbine Trip Due to High Turbine Bearing Vibrations
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED FAcILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR NUMBER NO.
NA NA FACILITY NAME DOCKET NUMBER 04 10 2009 2009 002 00 06 08 2009 NA j
NA
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply) 0 20.2201(b)
C1 20.2203(a)(3)(i)
[] 50.73(a)(2)(i)(C)
[I 50.73(a)(2)(vii)
N 0l 20.2201(d)
El 20.2203(a)(3)(ii)
El 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)
CD 50.73(a)(2)(viii)(B)
El 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 Cl 20.2203(a)(2)(ii)
Cl 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(iv)(A)
Cl 50.73(a)(2)(x)
El 20.2203(a)(2)(iii)
El 50.36(c)(2)
[1 50.73(a)(2)(v)(A)
El 73.71(a)(4) 0l 20.2203(a)(2)(iv)
[1 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
Cl 73.71(a)(5) 028 El 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)
El 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in
D. DATES AND APPROXIMATE TIMES OF MAJOR OCCURRENCES
April 10, 2009, 0220:
Operators commenced placing second stage reheaters in service.
April 10, 2009, 0312:
Turbine vibration started to rise.
April 10, 2009, 0523:
Turbine Bearing Number 4 High Vibration Alarm received and Alarm Response Procedure entered.
April 10, 2009, 0532:
Emergency power reduction commenced in accordance with a Special Operating Procedure.
April 10, 2009, 0538:
Turbine manually tripped. The HPCI System initiated automatically.
April 10, 2009, 1108:
After completion of immediate corrective actions, turbine roll commenced.
April 10, 2009, 1139:
Generator synchronized to the grid.
E. OTHER SYSTEMS OR SECONDARY FUNCTIONS AFFECTED
None.
F. METHOD OF DISCOVERY
This event was immediately apparent by control room indications.
G. MAJOR OPERATOR ACTION:
Operators failed to maintain a heat up rate of not more than 3 degrees/min with less than 50 degrees difference between the reheaters. To prepare for a potential manual turbine trip, operators reduced the reactor power to provide margin for reactor pressure control on the turbine bypass valves. The turbine was manually tripped. The HPCI initiation signal was reset. After determining and addressing the cause of the vibration, the turbine was restarted and the generator was synchronized to the grid without any complications.
H. SAFETY SYSTEM RESPONSES:
The HPCI System initiated upon turbine trip as designed. The HPCI System is a mode of operation that uses selected equipment of the Condensate and Feedwater System to perform its function. The HPCI system is not an ECCS.
II. CAUSE OF EVENT
The cause of this event is failure to follow the operating procedure for placing the second stage reheaters in service. The procedure guidance required raising the second stage reheater tube temperatures at a maximum rate of 3 degrees F per minute while placing the second stage reheaters in service. The procedure guidance also required limiting the temperature differential between the left and the right sides of the turbine to 50 degrees F. The operators Utilized an average heat rate of 3 degrees F per minute for the second stage reheater's tube temperatures while placing the second stage reheaters in service. This resulted in reheater outlet temperature varying more than 50 degrees F between the left and the right sides of the turbine causing a turbine rub.
NMP Condition Report (CR) 2009-002238 applies to this LER.
Ill. ANALYSIS OF THE EVENT:
This event is reportable in accordance with 10 CFR 50.73(a)(2)(iv)(A) which states that any event or condition that resulted in manual or automatic actuation of any of the systems listed in paragraph 10 CFR 50.73(a)(2)(iv)(B) is reportable. The NMP1 HPCI System is a feedwater coolant injection system, which is one of the systems listed 10 CFR 50.73(a)(2)(iv)(B).
There were no equipment failures associated with this event, and all safety related structures, systems, or components performed per design. Therefore, there was no adverse impact on the operability/functionality of any safety related structures, systems, or components associated with this event. It is therefore concluded that had a design bases accident occurred coincident with this event, plant systems would have responded per design to mitigate the accident.
As plant systems performed per design and plant parameters (other than turbine vibrations) remained within normal bounds throughout this event, this event did not pose a significant threat to the health and safety of the public or plant personnel.
IV. CORRECTIVE ACTIONS
A. ACTION TAKEN TO RETURN AFFECTED SYSTEMS TO PRE-EVENT NORMAL STATUS:
The HPCI System initiation signal was immediately reset following the turbine trip.
B. ACTION TAKEN OR PLANNED TO PREVENT RECURRENCE:
NOTE: There are no NRC regulatory commitments in this LER.
To prevent recurrence, the applicable operating procedure has been revised to include better guidance on placing second stage reheaters in service. In addition, pre-outage Just-In-Time training material will be revised to include proper placement of second stage reheaters in service and to review this event as an internal operating experience event.
V. ADDITIONAL INFORMATION
A. FAILED COMPONENTS:
None.
B. PREVIOUS LERs ON SIMILAR EVENTS:
None.
C. THE ENERGY INDUSTRY IDENTIFICATION SYSTEM (EIIS) COMPONENT FUNCTION IDENTIFIER AND SYSTEM NAME OF EACH COMPONENT OR SYSTEM REFERRED TO IN THIS LER:
COMPONENT IEEE 803 FUNCTION IDENTIFIER IEEE.805 SYSTEM IDENTIFICATION TB Generator GEN High Pressure Coolant Injection System Reheater Turbine D. SPECIAL COMMENTS:
None.
NA RHTR BJ SN TA TRB