ML20058C645
| ML20058C645 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 10/25/1990 |
| From: | Devine J GENERAL PUBLIC UTILITIES CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML20058C647 | List: |
| References | |
| C320-90-806, NUDOCS 9011020153 | |
| Download: ML20058C645 (2) | |
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OPU Nuclear Corporation N
le8r One Upper Pond Road Parsippany, New Jersey 07054 201 316 7000 TELEX 136-4;2 Writer's Direct Dial Number:
October 26, 1990 5000-90-1984 C320-90-806 United States Nuclear Regulatory Commission Attention: Document Control Desk Mailing Station PL-137 Washington, D.C.
-20555 Gentlemen
SUBJECT:
Oyster Creek Nuclear Generating Station Docket Number 50-219 License DPR-16 Generic Letter 88-01 Weld overlay Procedure Development for Water-Backed Nozzle-To-Safe-End Welds EPRI and othur industry organizations have initiated work to develop repair methods for nozzle-to-safe-end welda containing Inconel 182 filler metal.
Oyoter Creek is constructed with safe-ends employing this type of weldment.
During the 13R refueling outage, GPU Nuclear will be performing ultraconic examinations on four (4) welds of this type.
Since the potential for finding indications of IGSCC in these weldments exjsts, CPUN is preparing for this contingency.
GPUN has contracted Nutech engineers to develop a wtter-backed method to perform weld overlay repatro to this type of joint. GPUN_has anticipated this need for the following reasonst i
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Inconel 182 is an IGSCC susceptible material.
2.
Inlet recirculation safe-ends to be examined in the future have Very tight restrictions with respect to the bio-shield openings.
Because of this restriction, methods of preheat and post weld heat treatment, involving heating coils and blankets-would be very j
difficult to employ in using ASME Code Case 432.
9011020153 901025 nO\\
PDR ADOCK 05000219 V'
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GPU Nuclear Corporation is a subsidiary of General Public Utilities Corporation
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C320-90-806 Page 2 3.
Bochuse it is unknown when a prospective repair might be required during the outage, plant condition requirements to invoke Code Case 432 could require an additional core off-load and reactor vessel draindown.
Both of these evolutions are major changes in plant conditions with an attendant increase in personnel radiation exposure in performing drywell outage work.
The attached report describes the technical issues concerned with the contingency repair process GPUli believes may be utilized for weld repair during the upcoming outage.
The process of submitting it to ASME for review has begun. Because GPUN senses a strong need to have this contingency plan available for 13R, we request that the staff review the subject method. Formal approval will be requested when GPUN decides that repairs using this process will be required during the 13R outage.
The 13R outage is currently scheduled to begin in February 1991.
In the event comments or questions relative to the. review arise, please contact Mr. M. Laggart, Manager Corporate Licensing, at 201-316-7968.
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Verytrulyhadre, f
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J. C. DeVine, Jr.
Vice President and Director Technical Functions l
JCD/BMP/amk C32206 cca Administrator Region I U.
S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 i
l NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ- 08731 Mr. A'sx Dromerick, Jr.
I U. S. Nuclear Regulatory Commission Mail Station P1-137 Washington, DC 20555 i
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