ML20134H654
| ML20134H654 | |
| Person / Time | |
|---|---|
| Site: | Palisades  |
| Issue date: | 11/07/1996 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML20134H647 | List: |
| References | |
| NUDOCS 9611140213 | |
| Download: ML20134H654 (3) | |
Text
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k UNITED STATES p
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j NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20066 4 001
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l SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 175 TO FACILITY OPERATING LICENSE NO. DPR-2G i
CONSUMERS POWER COMPANY PALISADES PLANT s
l DOCKET NO. 50-255 l
1.0 INTRODUCTION
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By letter dated August 14, 1996, as supplemented October 18, 1996, Consumers Power Company (the licensee) requested an amendment to the Technical Specifications (TS) appended to Facility Operating License No. DPR-20 for the Palisades Plant. The proposed amendment requested a one-time deferral of the inspection of reactor coolant pump (RCP) flywheels from the Cycle 12 refueling outage scheduled to begin on November 2, 1996, to the next refueling outage.
1 The October 18, 1996, letter provided an updated TS page. This change was within the scope of the original application and did not change the staff's initial proposed no significant hazards consideration determination.
This submittal is related to an earlier TS change request dated January 18, j
1996, which was submitted with a supporting document, Topical Report SIR-94-080, " Relaxation of Reactor Coolant Pump Flywheel Inspection Requirements." Since this topical report is identical to the one that was submitted by Entergy Operations on April 4, 1995, for Arkansas Nuclear One (ANO) Units 1 and 2 as the lead plants for the topical report review, the staff would still consider Entergy Operations as the point of contact for any matter concerning the review of the topical report. The topical report was developed by Structural Integrity Associates, Inc. (SIA) to provide a basis for the complete elimination of the RCP flywheel inspections for Combustion Engineering Owners Group (CE0G) plants including ANO Units 1 and 2, Millstor,e Unit 2, Palisades, St. Lucie Units 1 and 2, and Waterford Unit 3.
Since the projected date of issuance of the staff's safety evaluation report for '.he topical report review is beyond the 1996 outage of Palisades, the licensee made this request for a one-cycle deferral of the flywheel inspection.
2.0 BACKGROUND
10 CFR Part 50, Appendix A, General Design Criterion 4 (GDC 4), requires that structures, systems, and components important to safety be protected against the effects of missiles that might result from equipment failures.
In accordance with the inspection guidelines of Regulatory Guide 1.14, " Reactor Coolant Pump Flywheel Integrity," the licensee specifies in TS 6.5.6 (formerly TS Table 4.3.2) that a 100% volumetric examination of the upper primary (reactor) coolant pump flywheels be conducted at each refueling outage.
From 1970 to 1993, the licensee had conducted 11 ultrasonic testing (UT) examinations of all four RCP flywheels at an average interval of 2.2 years.
9611140213 961107 PDR ADOCK 05000255 P
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l l 3.0 EVALUATION i
Consumers Power Company and certain other CE plant licensees, working through the CEOG contracting with SIA, performed fracture mechanics analyses to i
justify elimination of the inspection requirement in the TS. SIA conducted an j
evaluation and analyses of flywheel integrity including plant-specific data from ANO Units 1 and 2, St. Lucie Units 1 and 2, Millstone Unit 3, Palisades, j
and Waterford Unit 3.
The SIA analyses included a review of flywheel designs, materials, inspection results, stress and fracture mechanics analyses, and American Society of Mechanical Engineers (ASME) Code allowable flaw sizes.
2 The Palisades flywheel assembly is of the " hollow" type with its larger flywheel fitted over a spoked center section and bolted down to a smaller i
separate bore lower flywheel. The top flywheel has a bore of 34 inches, an j
outside diameter of 72 inches, and a thickness of 7 inches. The keyway is 0.5 i
inch wide and 0.25 inch deep. The material is ASTM-A-108 low carbon steel.
i The top wheel is much larger in diameter than the bottom wheel, therefore, j
testing and analysis is pei formed on the top flywheel only.
From 1970 to 1993, the licensee followed the TS requirements and had completed 11 j'
volumetric examinations of all four RCP top flywheels at an average interval of 2.2 years.
From these inspection results, the licensee did not identify any indications that present structural integrity concerns or conditions that j
could lead to the failure of a flywheel.
l The staff's review of the fracture mechanics analyses in SIR-94-080 was delayed pending receipt of information from Entergy Operations, which includes (1) demonstration of member plants' UT detection capability to detect flaw l
sizes of 0.25 inch, (2) a revised copy of Figures 6-3 to 6-14 to add the stress intensity factor due to shrink fit at the proper speed to the stress intensity factor due to centrifugal load, (3) the remaining shrink fit for i
accident conditions for all flywheels, and (4) past RCP flywheel maintenance i
records in terms of maintenance frequency and level of disassembly involved.
Information regarding the first three items is needed for the staff to resume the review of SIR-94-080. The fourth is needed in case any special j
consideration will be given to the flywheels of CE0G plants.
Regardless of the pending additional information, the staff determined that the proposed inspection deferment for one operating cycle would not adversely affect the structural integrity of the flywheels. This decision is based on (1) the favorable results from all 11 volumetric examinations conducted by i
Palisades since 1970, (2) the plant's lower operating speed of 900 rpm and design overspeed of 1125 rpm as compared to the industry norm of 1200 rpm and 1500 rpm,-and (3) the much shorter time involved in the requested one-cycle deferral as compared to the complete elimination of the inspection requirement from the TS as requested in the January 18, 1996, submittal. Based on these i
considerations, the flywheel inspection may be deferred from the Cycle 12 refueling outage scheduled for November 2,1996, to the next refueling outage.
4 Therefore, the staff finds the proposed TS change to be acceptable.
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4.0 STATE CONSULTATION
l In accordance with the Commission's regulations, the Michigan State official was notified of the proposed issuance of the amendment. The Michigan State official had no comments.
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5.0 ENVIRONMENTAL CONSIDERATION
The amendment changes a requirement with respect to the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and changes a surveillance requirement. The staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposeo finding that the amendment involves no significant hazards consideration and there has been no public comment on such finding (61 FR 50054). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement cr environmental assessment need be prepared in connection with the issuance of the amendment.
6.0 CMCLUSION il The staff has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner. (2) such activities will be conducted in compliance with the Commission's regulations, i
and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
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{
Principal Contributor: S. Sheng
}
Date:
November 7, 1996 4
l l-i d
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'o DATED:
November 7, 1996
- AMEN 0 MENT NO./7f70 FACILITY OPERATING LICENSE NO. DPR-20-PALISADES-Dociet311e:-
PUBLIC' PDIII-I Reading J. Roe C. Jamerson R. Schaaf OGC G. Hill (2)'
C. Grimes, 0-IIF23 S. Sheng ACRS L. Miller, RIII SEDB 1
'