ML15264A270
| ML15264A270 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 01/28/1985 |
| From: | Stolz J Office of Nuclear Reactor Regulation |
| To: | Tucker H DUKE POWER CO. |
| References | |
| GL-83-28, NUDOCS 8502130136 | |
| Download: ML15264A270 (5) | |
Text
- JA 2B 85
-4 Dockets Nos. 50-269, 50-270 DISTRTBUTION and 50-287 o
HNicolaras NRC PDR RIngram L PDR Gray File ORB#4 Rdg LO1shan Mr. H. B. Tucker DEisenhut EBlackwood Vice President - Steam Production OELD HOrnstein Duke Power Company EJordan P. 0. Box 33189 PMcKee 422 South Church Street ACRS-10 Charlotte, North Carolina 28242 JPartlow
Dear Mr. Tucker:
SUBJECT:
REQUEST FOR ADDITIONAL INFORMATION OF GENERIC LETTER 83-28, ITEMS 4.2.1 AND 4.2.2 Re:
Oconee Nuclear Station, Units 1, 2 and 3 We have reviewed your November 4, 1983 response to Generic Letter 83-28, "Required Actions Based on Generic Implications of Salem ATWS Events."
Specifically, we reviewed your letter-with respect to Items 4.2.1 and 4.2.2, "Preventative Maintenance Program for Reactor Trip Breaker/Maintenance and Trending".
Based on our review, we have determined that we.need additional information to complete our evaluation. We request that you respond to the enclosed list of questions within 30 days of the date of this letter. This request for information affects fewer than ten respondents; therefore, OMB clearance is not required under P.L.96-511.
Sincerely, "IR IGISAL SIGNED B John F. Stolz, Chief Operating Reactors Branch #4 Division of Licensing
Enclosure:
Request for Additional Information cc w/enclosure:
See next page 94HDaras;cf J lJ/85 1/ 7 5 8502130136 850128 PDR ADOCK 05000269 P
Duke Power Company cc w/enclosure(s):
Mr. William L. Porter Duke Power Company P. 0. Box 33189 422 South Church Street Office of Intergovernmental Relations Charlotte, North Carolina 28242 116 West Jones Street Ral-eiqh, North Carolina 27603 Honorable James M. Phinney County Supervisor of Oconee County Walhalla, South Carolina 29621 Mr.
James P. O'Reilly, Regional Administrator U. S. Nuclear Regulatory Commission, Region II 101 Marietta Street, N1, Suite 2900 Atlanta, Georgia 30323 Heyward G. Shealy, Chief Bureau of Radiological Health South Carolina Department of Health and Environmental Control Regional Radiation Representative 2600 Bull Street Columbia, South Carolina 29201 EPA Region IV 345 Courtland Street, N.E.
Atlanta, Georgia 30308 Mr. J. C..Bryant Senior Resident Inspector U.S. Nuclear Regulatory Commission Route 2, Box 610 Seneca, South Carolina 29678 Mr. Robert B. Borsum Babcock & Wilcox Nuclear Power Generation Division Suite 220, 7910 Woodmont Avenue Bethesda, Maryland 20814 Manager, LIS NUS Corporation 2536 Countryside Boulevard Clearwater, Florida 33515 J. Michael McGarry, III, Esq.
Bishop, Liberman, Cook, Purcell & Reynolds 1200 17th Street, N.W.
Washington, 0).
C. 20036
OCONEE UNITS 1, 2 AND 3 REOUEST FOR ADDITIONAL INFORMATION GL 83-28, ITEMS 4.2.1 AND 4.2.2 Item 4.2.1 -
Periodic Maintenance Program for Reactor Trip Breakers.
1.1 Criteria for Evaluating Compliance with Item 4.2.1 The Oconee Units 1, 2 and 3 Reactor Trip Systems utilize General Electric AK-2A circuit breakers. The primary criteria for an acceptable maintenance program for this breaker are contained in Maintenance Instruction GEI-50299EI*, "Power Circuit Breakers, Types AK-2/2A-15, AK-2/3/2A/3A-25, AKU-2/3/2A/3A-25," and Service Advice 9.3S and 9.20, by General Electric. The staff has reviewed these items and endorsed the maintenance program they describe.
More specifically, the criteria used to evaluate compliance include those items in the General Electric instructions and advisories that relate to the safety function of the breaker, supplemented by those measures.that must be taken to accumulate data for trending. The acceptable maintenance activity interval is six months.
1.2 Issues Relating to Item 4.2.1 Your response states that preventative maintenance on the Reactor Trip Breakers is performed at six month intervals and that the Oconee maintenance program meets the intent of GE Service Advice 175-9.3S. The submittal also states that the undervoltage trip attachment (UVT) will not be removed to verify clearance between rivet and armature as specified in 175-9.3S, item #S1, because the removal/replacement of the UVT could create an additional physical interference through improper reinstallation. No.procedures were included with the submittal.
The Oconee Units 1, 2 and 3 periodic maintenance program for the reactor trip breakers should include, on a six month basis:
- 1. Verification of.breaker cleanliness and insulation structure; all foreign materials, such as'paint, dust, or oil, should be removed to prevent electrical breakdown between points of different potential;
- 2.
Verification of breaker physical condition, including wiring insulation and termination, all retaining rings, pole bases, arc quencher, stationary and movable contacts, and tightness of nuts and bolts;
-2
- 3. Verification of proper manual operation of the breaker, including checks for excessive friction, trip bar freedom, latch engagement, operating mechanism alignment and freedom, and undervoltage trip (UVT) device armature freedom;
- 4. Verification of the optimum freedom of the armature as specified in General Electric Service Advice 175-9.3S, item #S1;
- 5. Verification of proper trip latch engagement as specified in Service Advice 175-9.3S. item #S2;
- 6. Verification of undervoltage pick-up setting, as specified in Service Advice.175-9.3S, item #S3, and dropout voltage;
- 7. Verification that the trip torque required on the trip shaft is less than 1.5 pound-inches, as specified in Service Advice 175-9.35, item #S4; "Before" and "After" maintenance torque values should be recorded;
- 8. Verification of positive tripping by checking the adjustment between the UVT device and trip paddle as specified in Service Advice 175-9.3S, item #S5;
- 9. Verification of proper trip response time as specified in Service Advice 175-9.3S, item #S6;
- 10. Lubrication of trip shaft and latch roller bearings with Mobil 28 lubricant;
- 12. Examination and, cleaning of breaker enclosure;
- 13. Functional test of the breaker prior to returning it to service.
You are requested to confirm that the periodic maintenance program includes these 13 items at the specified interval or commit to their inclusion and provide a date by which they will be included.
- 2. Item 4.2.2 - Trending of Reactor Trip Breaker Parameters of Forecast Degradation of Operability.
2.1 Criteria for Evaluation Compliance with Items 4.2.2 Four parameters have been identified for trending and are included in the criteria for evaluation. These are (1) undervoltage trip attachment dropout voltage.,-(2) trip torque, (3) breaker response time for undervoltage trip, and (4) breaker insulation resistance.
-3 2.2 Issues Relating to Item 4.2.2 Your submittal does not address the matter-of parametric trending to forecast degradation of reactor trip breakers.
You are requested to commit to inclusion of trip torque, breaker response time and dropout voltage for undervoltage trip and breaker insulation resistance, as trending parameters. You should also identify the organization which will perform trend analysis, how often the analysis will be performed and how the information derived from the analysis will be used to affect periodic maintenance..