ML20113F776
| ML20113F776 | |
| Person / Time | |
|---|---|
| Site: | Byron, Braidwood, 05000000 |
| Issue date: | 01/16/1985 |
| From: | Swartz E COMMONWEALTH EDISON CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML20113F780 | List: |
| References | |
| 9634N, NUDOCS 8501240130 | |
| Download: ML20113F776 (2) | |
Text
n a
4 [,
) One First Nativl Plus, Chicago, Illinois Commonwealth Edison v
o y;
.(
~ 5 Address Riply tr Past Offics Box 767
(
Chicago, Illinois 60690 January 16, 1985 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 Pipe Whip Restraints Utilizing Crushable Energy Absorbing Material NRC Docket Nos. 50-454/455 and 50-456/457 References (a):
E. D. Swartz letter to J. G. Keppler dated April 13, 1984
~
(b):
E. D. Swartz letter to H. R. Denton dated September 25, 1984 (c):
E. D. Swartz letter to J. G. Keppler dated December 18, 1984
Dear _Mr. D,
enton:
-The purpose of this letter is to provide NRR with the Sargent & Lundy Report No. SAD-454, Revision 0 dated January 1985.
This report addresses the Byron Unit I license conditions concerning pipe whip restraints utilizing energy absorbing material (EAM) contained in Attachment 1 Items D.4.a, D.A.b and D.A.c, and we believeEthat NRR review of this material will resolve these remaining open EAM issues.
The enclosed report No. SAD-454 describes the sensitivity analysis for restraint SI3R-640A evaluating the effects of the variation in EAM crush strength on the function of the restraint in order to satisfy. Item D.4.a.
This analysis concludes that the restraint will perform its intended. function for a range of EAM crush strengths which envelop the crush strength values obtained in the Byron angular tests.
The report further compares the Byron /Braidwood angular test configuration against the LaSalle County off axis test configuration to satisfy Item D.4.b.
This comparison-shows that the different conclusions reached are related to the differences in the EAM load angularity in the two test configurations, in addition to various factors contributing to the differences which are also discussed.
Further, the report provides the results of the effective off set angle calculations for the Byron restraints to satisfy Item D.4.c.
Reference (b) provided the Sargent & Lundy Report No.
SAD-443, Revision 0 dated September 1984.
In this report, on page ggggp l IV-12, we' stated that it was our judgement that a 30 percent 8501240130 850116 PDR ADOCK 05000454 gall
_j P
i D
s reduction in the computed force magnitude for the one million pound instrument tup measurements was appropriate.
However, to confirm our judgement, we committed to recalibrate the instrument tup and revise the Sargent & Lundy Report No. SAD-431 as necessary to account for the results of the recalibration.
Although outside the scope of the Byron Unit 1 license conditions contained in Attachment l' Items D.4.a, D.4.b and D.4.c, the enclosed Sargent & Lundy Report No. SAD-454, Revision 0 dated January 1985 additionally presents the results of the recalibration of both the new one million pound and the 350,000 pound instrument tups as discussed in Reference (b).
The EAM crush strengths.for all the test specimens were recomputed using the new calibration results, and it is shown the that new calculations support our original conclusions of Report SAD-431 concerning the EAM behavior.
Finally, enclosed are revised pages 1, iii, iv, 2, 3, 17, 18 and 21 to the Reference (a) Sargent & Lundy Report No. SAD-431, Revision 2 dated January 1985.
This revision is necessary to provide' correction for minor errors that were made in calculating the EAM dynamic crush strength and subsequently found as a result of our internal review.
These corrections do not change the conclusions of the report, and we apologize for any inconvenience that this revision may cause.
We believe that the enclosed information along with the previously provided Reference (c) material now completes all confirmatory measures related to the qualification of EAM applications in pipe whip restraints contained in the Byron Unit 1 license condition Attachment 1 Item D, and which are required prior to_ exceeding 5 percent power.
In order to prevent an impact on our power ascension schedule,-we respectfully request that both NRR and Region III expeditiously complete their respective reviews of this information, along with all other previously subr.itted EAM information, and advise the Commonwealth Edison Company as to the statuslof closure of the EAM confirmatory issues.
Please address any questions concerning this matter to this office.
One signed original and fifteen ~ copies of this letter along with:the enclosed Sargent & Lundy Report SAD-454, Revision 0 dated January 1985, and revised pages to SAD-431, Revision 2 dated January 1985 are provided for your use.
Very truly you E.
augla Nuclear Licensing Administrator Enclosures cc:
J. G. Keppler - RIII J. Streeter - RIII J. A. Stevens - LB1 RIII Inspectors - By/BW 9634N
-