ML20248L481
| ML20248L481 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 06/05/1998 |
| From: | Terry C TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 50-445-98-02, 50-445-98-2, 50-446-98-02, 50-446-98-2, TXX-98144, NUDOCS 9806110182 | |
| Download: ML20248L481 (5) | |
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Log # TXX 98144 C
C File # 10130 1UELECTRIC.
IR 98 02
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Ref. # 10CFR2.201 c, %% -
' June 5, 1998-
, 5enfor McePresidmet :
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p & PrincipalMwlearOpicer 4 w MU[S,! NucleariRegulatory Commission 9'
.' Attn:. Document Control Desk ~
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l Washington, D;C 20555 jJo43: sui 3]ECT:
COMANCHE PEAK STEAM ELOCTRIC STATION (CPSES)
W R-DOCKET NOS. 50 445 and 50 446
.is NRC INSPECTION REPORT NUMBERS 50 445/98 02 and 50 445/98-02 L'*'
0 ADDITIONAL;INFORMATION RELATED TO TU ELECTRIC'S L
si' RESPONSE;TO THE NOTICE-0F VIOLATION g,
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REF:
C. L. Terry to the HRC dated May 22, 1998 c
1.
y Gentlemen:
LVia Reference 1). TU Electric responded to Notice of Violation item
'50.445/9802-06 associated with the number of starts of the safety injection ipump motor.
In4the response TU Electric denied violation item 50 445/9802 06. TU Electric has further considered the denial of this
,' Q: r m violation and provides the, following additiona1'information related to this L':
'-issue.
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TU Electr'ic continues to believe that a violation of 10 CFR Part 50,
. Appendix B) Criterion XVI did not occur because.TU Electric believes that adequate corrective' actions were taken for this issue as described in Reference 1.).
.However, upon further consideration. TU Electric recognizes that the program weakness identified by.the inspection report (section b
E4.lb)'could potentially have been characterized as a violation.
Specifically, the program' weakness noted in the inspection report was that TU Electric's Equipment Qualification Program did not contain provisions to predict when equipment that was being operated at increased service
. conditions would need to be replaced, refurbished, or requalified.
.Therefore, in addition to the enhancements noted in Reference 1),
L TU Electric will' revise the Equipment Qualification Maintenance Manual 4'
(EQMM) to include information that will aid inidentifying when equipment is being cycled more frequently than'its routine operating service for
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I sustained periods of' time. This change will' allow equipment so identified to be reviewed to assure that cycle dependent electrical' equipment t
qualifications'are maintained.
The inclusion of this information will be F
reinforced with training. This training will emphasize the importance of
{M these requirements in ensuring equipment qualification is maintained.
9806110182 980605
- PDR ADOCM 0S000443 e
PDRm 1 *g - CiQ COMANCHE PEAK STEAM TLECTRIC STATION P.O. Box 1002 Glen Rose Texas 7604).1002
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TXX,98144 Page 2 of'3 It should be noted that this type of review was conducted for the Safety Injection pumps as part of the corrective actions performed for the issues identified.
Via this correspondence TU Electric withdraws its formal denial of the violation. The information requested by the Notice of Violation is attached.
This communication contains the following new commitments which will be completed as noted:
CDF Number Commitment 27141 TV Electric will revise the Equipment Qualification Maintenance Manual (EQMM) to include information that will aid in identifying when equipment is being cycled more frequently than its routine operating service for sustained periods of time.
27142 The inclusion of information in the EQMM will be reinforced with training. This training will emphasize the importance of these requirements in ensuring equipment qualification is maintained.
The CDF number is used by TV Electric for the internal tracking of CPSES con:mitments.
Should you have any ccaments or require additional information, please do not hesitate to contact Gary Merka at (254) 897-6613 to cocrdinate this effort.
Since e Ox C. L. Terry GLH:g1m c-Mr. E. W. Herschoff Region IV Mr. J. I. Tapia, Region IV Resident Inspectors Mr. T. J. Polich, NRR
~ Attachment,to TXX 98144 Page l'of 3 RESPONSE TO THE NOTICE OF VIOLATION RESTATEMENT OF THE VIOLATION l
(50 145(446)/9802-06)
C. 10 CFR Part 50, Appendix B Criterion XVI, " Corrective Action," states that measures be ' established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected.
Contrary to the above, corrective: actions were not sufficient to identify that excessive leakage in the emergency core cooling-system check valves during Unit 1. Cycle 6 required the Unit 1 safety injection pumps to be started 30 times per month, which was 15 times greater than that assumed in the equipment qualification data package for the Westinghouse
" Lifeline D" motors. As a result of the failure to identify this condition, the licensee could not determine if the safety injection pump
- motors had exceeded their. qualified lives.
This is a Severity Level IV violation (Supplement 1)
.(50 445(446)/9802 06);
RESPONSE TO THE VIOLATION (50 445(446)/9802-06)
)
.TV Electric accepts the violation, the response as requested is provided below:
- 1. Rea' son for Violation
.On June 24,1996, an' 0perations' Notification and Evaluation (ONE) Form was. initiated that identified an overpressure condition in the Safety Injection (SI). pump discharge header. The root cause of'this condition was determined to be leakage of Reactor Coolant System (RCS) pressure i
boundary check valves. As a result of the leakage, the SI pumps were required to be started 1 3 times per shift to refill the accumulators.
-The immediate corrective actions taken were.to 1) evaluate the piping and components subjected to the increased pressure: 2) evaluate Technical Specification RCS leakage Limits: 3) evaluate the simmering phenomena of
'the relief valves: 4) initiate shiftly surveillance of the SI pesp i
discharge header pressure: and 5) add an additional relief valve and flow measuring device between'the SI pump and the existing relief valves. The long term corrective action was to replace the check valves with later
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' generation. valves with highly polished disks.. The above corrective
' actions.are documented in the original ')NE Form disposition.
'In addition to the above actions,- TU Electric contacted the NSSS vendor i
(Westinghouse) in January 1997 to evaluate the impact on the SI pump and motor due to the numerous starts associated with refilling the i
l accumulators. The evaluation by the NSSS vendor noted that the starts l
would not significantly affect the motor. However, the pump might be
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Attachment,to TXX 98144 Page 2 of 3 subject to adverse wear.
Based on the vendor's response, TU Electric enhanced the surveillance of these pumps by increasing the frequency of the bearing vibration measurements and also the frequency of the lube oil analysis.
The number of cycles listed in the EQ package (1992) was not provided by the original equipment manufacturer, but was derived by TU Electric based on the r. umber of anticipated starts.
It was neither derived from end of life data nor was it intended to represent end of life.
The primary concern for cycling these types of motors has been rotor bar cracking. The large safety related motors for CPSES (SI, RHR, etc.) are Life Line D (LLD) design which have swaged rotor bars as compared to older designs which have unswaged rotor bars, and therefore were susceptible to rotor bar cracking as a result of frequent starting.
There have been no known problems with rotor bar cracking in the LLD designs.
During the development of the LLD designs, testing was performed which indicated that motors with swaged rotor bars were capable of well in excess of 50,000 starts without any problems with the rotor bars.
Based on the above, there are no concerns due to the number of starts on these motors.
TV Electric continues to believe that a violation of 10 CFR Part 50, Apptndix B.-Criterion XVI did not occur because TV Electric believes that adequate corrective actions were taken for this issue.
However, TU Electric recognizes that the program weakness identified by the NRC in the inspection report could potentially have been characterized as a violation.
Specifically, the program weakness noted in the inspection report was that TV Electric's Equipment Qualification Program did not contain provisions to predict when equipment that was being operated at increased service conditions would need to be replaced, refurbished, or requalified. Although some procedural guidance was present in this area, it may have been less than adequate without the appropriate training of operations and system engineering personnel to reinforce the need to consider the equipment qualification aspects of non normal operational events.
- 2. Corrective Steos Taken and Results Achieved The long term corrective action of replacing the check valves was implemented at the first available opportunity on Units 1 and 2, (sixth refueling outage on Unit 1 and fourth refueling outage on Unit 2).
Based on the above discussion, TV Electric believes all appropriate corrective actions were taken for the condition identified on June 24, 1996.
The following enhancements have been completed: 1) the original ONE Form has been supplemented to document the NSSS supplier's evaluation of the pump and motor starts and the additional pump surveillance performed,
- 2) a training memo has been issued to Operations and System Engineering personnel reinforcing the need to consider the equipment qualification aspects of non normal operational events, and 3) the SI pump motor EQ package has been revised to document the acceptability of this operating condition.
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' Attachment,to TXX 98144 Page 3 of 3
- 3. Corrective Actions ~ Taken to Preclude Recurrence TU Electric will revise the Equipment Qualification Maintenance Manual
.(EQHM) to include information that will aid in identifying when equipment is being cycled more frequently than its routine operating service for sustained periods _ of time. This change will allow equipment so identified to be reviewed to assure that cycle dependent electrical equipment qualifications are maintained. The inclusion of this information will be reinforced with training. This training will emphasize the importance of these requirements in ensuring' equipment qualification is maintained.
- 4.. Date of Full Como11ance TU Electric is in full compliance based on the corrective actions completed.-
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