ML19332A064
| ML19332A064 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 09/03/1980 |
| From: | Mayer L NORTHERN STATES POWER CO. |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML19332A065 | List: |
| References | |
| NUDOCS 8009100500 | |
| Download: ML19332A064 (2) | |
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NORTHERN STATES POWER COMPANY miss eweou s. mis s c oorA ss4oi September 3, 1980 Director of Nuclear Resctor Regulation U S Nuclear Regulatory Commission Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PLANT Docket No. 50-282 License No. DPR-42 50-306 DPR-60 Information Required for NRC Review of Inservice Inspection and Testing Program and Requests for Relief from ASME Code Section XI Requirements Attached for your review you will find 40 copies of Revision Number 5 to our report entitled, "ASME Code Section XI Inservice Inspection and Testing Program and Information Required for NRC Review of Requests for Relief from ASME Code Section XI Requirements." This is a revision of our inservice
,q inspection and testing program description and requests for relief submitted
(
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to the Commission on February 1, 1978. Two program changes are proposed.
w-The first program revision changes the inspection schedule for reactor vessel safety injection nozzles. Two nozzles are installed in each vessel to deliver low and head safety injection flow to the upper plenum region.
Inspection of one of the nozzles in each unit was origi -
scheduled to take place with the core barrel installed.
Use of the k 1 < >. g-house Reactor Vessel Inservice Inspection (ISI) Tool was planne fn '.
inspection, however, Westinghouse has been unable to develop a rei-te inspection head for the relatively small injection nozzles which will accomodate expected vessel to core barrel misalignments. We propose inspection of both injection nozzles during the ten year inspection when the core barrel is removed and the reactor vessel inlet nozzles are inspected as an alternative schedule.
The program currently requires examination of 33% of the vessel to flange weld and the vessel flange ligaments with the Westinghouse's ISI Tool during each of the three inspection periods.
This requires the removal of the guide studs during the second and third inspection period ot the ten year interval. We now believe that it is not prudent to handle the upper reactor internals without the guide studs in place. Therefore, we have reduced the amount of inspection during the second inspection period to a minimum of 17%, and have increased the amount of inspection during the third period to 50%. This change in the amount of inspection for each of the three inspection periods still meets the ASME Section XI Code requirements.
8009100 500
. NORTHERN STATEC POWER COMPANY t-i
[
Director of Nuclear Reactor-Regulation September 3, 1980 Page 1 9
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Instructions are provided for entering Revision 5 in the original February 1, 1978 report. Please contact us if you have any questions related to this revision.
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k L 0 Mayer, PE Manager of Nuclear Support Services LOM/DMM/jh i
cc: J G Keppler i
G Charnoff i
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