ML17262A751
| ML17262A751 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 02/21/1992 |
| From: | Mecredy R ROCHESTER GAS & ELECTRIC CORP. |
| To: | Andrea Johnson NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation |
| References | |
| IEB-89-001, IEB-89-1, NUDOCS 9203030118 | |
| Download: ML17262A751 (8) | |
Text
'ACCELERATED DISTRIBUTION DEMONS TION SYSTEM REGULAT INFORMATION DISTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9203030118 DOC.DATE: 92/02/21 NOTARIZED:
NO DOCKET I FACIL:50>244 Robert Emmet'inna Nuclear Plant, Unit 1, Rochester G
05000244 AU'ZH.NAME AUTHOR AFFILIATION MECREDY,R.C.,
Rochester Gas
& Electric Corp.
RECIP.NAME
'ECIPIENT AFFILIATION JOHNSON,A.R.
Project Directorate I-3
SUBJECT:
Responds to NRC 911127 request for addi info re util response to Suppl 2 to NRC Bulletin 89-001, "Failure of Westinghouse Steam Generator Tube Mechanical Plugs" covering
. methodology for operating Alloy 600 mechanical plugs.
DISTRIBUTION CODE:
IE31D COPIES RECEIVED:LTR
(. ENCL
/C SIZE:
TITLE: Bulletin Response 89-01 re Failure of Westinghouse Steam Gen.
Mech.
T NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72).
05000244 RECIPIENT ID CODE/NAME PD1-3 LA JOHNSON,A INTERNAL: AEOD/DOA NRR/DET/EMEB 7E NRR/DOEA/OGCB11 REG RGN1 FILE 01 EXTERNAL: NRC PDR COPIES L'TTR ENCL RECIPIENT ID CODE/NAME PD1-3 PD NRR/DET/EMCB 9H NRR/DOEA/OEABll NRR/DREP/PEPB9D NRR/PMAS/ILRB12 RES/DSIR/EIB NSIC COPIES-LTTR ENCL 1,
1 1
-1 1
NOTE TO ALL"RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WAFEE! CONTACT THE DOCUMENT CONTROL DESK, ROOM PI-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
A TOTAL NUMBER OF COPIES REQUIRED:
LTTR 16 ENCL
0 kalb ofw ROCHESTER GAS AND ELECTRIC CORPORATION
~
89 EAST AVENUE, ROCHESTER N.K 14649.0001 ROBERT C. MECREDY Vice Presideni Cinnl Hucfea< Producuon February 21',
1992 TELEPHONE AAEACOOEllS546 2700 U.S. Nuclear Regulatory Commission Document Control Desk Attn:
Allen R. Johnson Project Directorate I-3 Washington, D.C.
20555
Subject:
Response
to Request for Additional Information NRC Bulletin 89-01 Supplement 2
Failure of Westinghouse Steam Generator Tube Mechanical Plugs R.E.
Ginna Nuclear Power Plant Docket No. 50-244 Ref.
(a)
Letter from Robert C. Mecredy, RG&E to NRC (Johnson),
Subject:
Response
to Bulletin 89-01, Supplement 2,
dated July 29, 1991
Dear Mr. Johnson:
In your request for additional information letter'f November 27, 1991 concerning RG&E's response to NRC Bulletin 89-01 Supplement 2, you requested that RG&E provide the calculations and methodology on the correlation used by RG&E for estimating the operating lifetime of Westinghouse Alloy 600 mechanical plugs installed in the Ginna steam generators.
Your letter stated that this information was required since the RG&E estimates of mechanical plug effective full power days (EFPD) operating lifetime-differed from the correlation developed by Westinghouse in WCAP-12244, Revision 3, Addendum 2.
RG&E did not develop.
a separate correlation for estimating Westinghouse Alloy 600 mechanical plug EFPD operating lifetime.
The information provide by RG&E to the NRC in our reference (a) response to NRC Bulletin 89-01, Supplement 2 was based upon the Westinghouse correlation provided in WCAP-12244.
The actual mechanical plug EFPD operating lifetime used by RG&E for the hot leg mechanical plugs installed in the Ginna steam generators is 4734 EFPD as reported by Westinghouse on p.
47 of Table 2 in WCAP-12244.
Consequently, RG&E does not have any plant specific correlation to provide to the NRC.
~g3/
i/ p As discussed in reference (a), the only changes that RG&E made to the data presented by Westinghouse in WCAP-12244 were the calculations for the cumulative
- EFPDs, remaining
- EFPDs, and year-to-repair for the Ginna mechanical plugs.
As shown on p.
47 of C=C <"..
ppn A000K 00000244
/PIffg t7p+OR Q
Table 2 in WCAP-12244, the Westinghouse estimates for cumulative EFPDs and remaining EFPDs were based on an assumed plant capacity factor of 70
%. This assumed plant capacity factor is non-conservative for the Ginna plant. Specifically, since Ginna's historical capacity factor has exceeded 70 4, the Westinghouse estimates for remaining EFPDs and repair year for the Ginna hot leg plugs were determined by RG&E to be too long. Consequently, RG&E re-estimated the remaining EFPDs for the hot leg plugs based on 1) actual EFPDs for the various batches of hot leg plugs up through the 1991 Refueling Outage and.
2) an RG&E projection of future plant capacity factors.
The actual values and methodology used by RG&E in performing this calculation to estimate the plug repair years was presented in our response to Item 1 of reference (a).
These results are summarized on the attached table which was included in reference (a).
The footnotes in the table have been added, for clarity.
A comparison of the RG&E estimates with the original Westinghouse estimates indicates that with the higher actual Ginna specific capacity factors, the repair years for the RG&E hot leg mechanical plugs is one year earlier than those estimated by Westinghouse in WCAP-12244.
We trust that the above discussion satisfies your request for additional information regarding-RG&E's estimates of mechanical plug lifetime. Please contact us, if you have any further questions or clarifications.
Very truly yours, Robert C. Mecredy GAH/209 xc:
Mr. Allen R. Johnson (Mail Stop 14D1)
Project Directorate I-3 Washington, D.C.
20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 Ginna Senior Resident Inspector
ROCHESTER GAS G ELECTRIC REVISIONS TO TABLE 2 OF ADDEliDUH 2 OF RCAP-12244, REV. 3 PLUG lHSTKL DATE 12-79 04-80 04-80 02-82 10-82 10-82 12-79 04-80 04-80 02-82 10-82 12-82 HO. OF PLUGS IHSTKLED 8
32 1
16 1
33 8
33 1
16 1
33 PLUG HEAT HO.
9789 9789 9789 1660 2386 2386 9789 9789 9789 1660 2386 2386 IHITIK EFPD TO HIH.
(A) 4734 4?34 4734 4734 4734 4734 53262 53262 53262 53262 53262 53262 REF.
CKC.
DATE 3/91 3/91 3/91 3/91 3/91 3/91 3/91 3/91 3/91 3/91 3/91 3/91 EFPD (1)
TO REF.
DATE (8) 3215 3120 3120 2615 2515 2515 3215 3120 3120 2615 2515 2515 REHAIH (2)
EFPD TO HIH.
(C) 1519 1614 1614 2119 2219 2219 50047 50142 50142 50647 50747 50747 YEAR TO (3)
PLUG 1996 1996 1996 1998 1998 1998
>2009
>2009
>2009
>2009
>2009
>2009 PLUGS REHOVED (1)
Actual. Hechanical Plug Operating Time Up Through 1991 Refueling Outage (2)
Col A - Col B (3) 1991 + (Col C/300); based on an assumed capacity factor of 82t (4)
From WCAP-12244, Table 2, p. 47, column (C)
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