ML19340E828
| ML19340E828 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 12/16/1980 |
| From: | Parker W DUKE POWER CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-79-02, IEB-79-2, NUDOCS 8101150907 | |
| Download: ML19340E828 (6) | |
Text
ke Duxe POWER COMPANY Powru Butt.ntwo 422 SouTu Curacu SrazzT. CiuatoTTE N. C. 2824a I
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December 16, 1980 V.Ct PersietmT TELEp owt: Anta 704 373-4093
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Mr. J. P. O'Reilly, Director U. S. Nuclear Regulatory Commission Region II 101 Marietta Street, Suite 3100 Atlanta, Georgia 30303 Re: McGuire Nuclea Jrtarinn Docket Nos40-369J0-370 7-IE Bulletin 79-02
Dear Mr. O'Reilly:
Attached is Revision 4 of Duke Power Company's response to IE Bulletin 79-02.
Based on discussions with the NRC during a meeting held on December 3-5, 1980, this revision documents our commitment to complete all necessary repairs prior to fuel loading on McGuire Unit 1.
Note that only page 1 of our response and pages 29, 30 and 31 of the statistical evaluation of anchor bolt safety factors have changed. These revised pages are attached and should be inserted in our submittal dated December 1, 1980 (Revision 3).
If you have additional questions regarding this matter, please advise.
A V y tru)y yours, /
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Lh. C WilliamO. Parker,Jr.[
LJB:scs Attachment cc: Director, Office of Nuclear Reactor Research Director, Inspection and Enforcement, Headquarters T. J. Donat, NRC Senior Resident Inspector, McGuire 8101.150907 O
6 MCGUIRE NUCLEAR STATION Responses to USNRC IE Bulletin 79-02, Revision 4 Original:
July 2, 1979 Revision 1:
January 7, 1980 Revision 2:
July 24, 1980 Revision 3:
December 3, 1980 Revision 4:
December 15, 1980 McGuire Nuclear Station is in the later stages of construction and very near completion and fuel load of Unit #1.
Essentially all pipe supports have been erected in Unit #1 and a large number have been erected in Unit #2.
The following is a summary, by item, of the extent and manner in which Duke Power Company intends to satisfy Actions 1 through 9 of the IE Bulletin 79-02, Revision 2.
Response 1:
Duke Power Company will account for base plate flexibility in the calculation of expansion anchor bolt loads for all Seismic Category I pipe support base plates using either a conservative hand calculation method which has been verified by non-linear finite element analysis or a specific non-linear finite element analysis for a particular base plate.
The models and boundary conditions, including appropriate load displacement character-istics of the anchors, used for ibe finite element analyses, are based on Duke studies and on work performed by Teledyne Engineering Services which was sponsored by a group of thirteen (13) utilities formed to respond to generic items of IE Bulletin 79-02.
All expansion anchor support plates designed prior to implementing these analysis methods are being reanalyzed accord-ingly and will be modified if required to comply with allowable anchor bolt loadings.
Response 2:
The minimum factors of safety, between the expansion anchor bolt design load and the bolt ultimate capacity determined from static load test, used in Duke's design of pipe supports, are as follows:
Normal Conditions 4
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Upset Conditions 4
l Faulted Conditions * -
4 f
These factors of safety are for wedge type and sleeve type i
expansion anchors.
Some shell type anchors were used in the early stages of McGuire construction.
Use of shell type anchors for Nuclear Safety Related applications was discontinued in i
February, 1975.
Duke Power Company has identified all pipe supports using shell type achors and the design of these sup-l ports has been reviewed to assure that a minimum factor of 1
safety of five (5) is maintained.
- For work completed prior to November 1, 1980, the 95% confidence level criteria, presented in the statistical analysis enclosed with this response, applies to faulted loading combinations.
The design criteria for all designs after that date require a minimum safety factor of 4 for faulted conditions.
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Duke Power Company McGUIRE NUCLEAR STATION ANCHOR BOLT SAFETY FACTOR ANALYSIS FOR USNRC I & E BULLETIN 79-02 l
AUGUST 8,1980 REVISED DECEMBER 1,1980 REVISED DECEMBER 8,1980 l
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4 11.5 IMPACT ON FUEL LOADING AND FULL POWER OPERATION Based on Duke's commitme nt in Revision 4 to the IEB 79-02 response, there is no impact of completing repairs on fuel loading or full power operation.
All repairs required to meet the requirements of IEB 79-02 will be completed prior to fuel loading.
11.6 PLAN OF CORRECTIVE ACTION All anchor bolts on each of the systems which did not meet the criteria will be screened, analyzed in detail, and repaired as necessary to achieve a condi-tion which meets the acceptance criteria, i.e. no more than 5% of the anchor bolts on that system with a safety factor less than 4.
This program will be similar to the hanger baseplate review which was done to consider baseplate flexibility. Also, we will expeditiously correct all bolts identified as having a safety factor less than A.
A summary of these activities and the time frame is presented below.
ACTIVITY TIME FRAME Upgrade to Meet 95% C. L. - Systems NF, VE, VG, Prior to Fuel Loading WS, W2, & YM Correct Bolts Identified w/ FS<4 Prior to Fuel Loading 29 Revision 4
THIS PAGE NOT USED l
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30 Revision 4
t THIS PAGE NOT USED 31 Revision 4