ML17264A418
| ML17264A418 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 03/22/1996 |
| From: | Mecredy R ROCHESTER GAS & ELECTRIC CORP. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| GL-95-03, GL-95-3, NUDOCS 9603290114 | |
| Download: ML17264A418 (7) | |
Text
CATEGORY 1 REGULATO!i INFORMATION DISTRIBUTION%STEM (RIDE)
ACCESSION A%BR:9603290114 DOC.DATE: 96/03/22 NOTARIZED: NO FACi.l:40-244-Robert Emmet Ginna Nuclear Plant, Unit 1, Rochester G
AU.H.NAMi~
AUTHOR AFFILIATION MECRFDY,R.C.
Rochester Gas
& Electric Corp.
RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)
SUBJECT:
Responds to NRC request for addi info re GL-95-03 dated 950627 re "Circumferential Cracking of Steam Generator Tubes".
DISTRIBUTION CODE:
AOOID COPIES RECEIVED:LTR
/ ENCL 8 SIZE:
TITLE: OR Submittal: General Distribution DOCKET N
05000244 A
NOTES:License Exp date in accordance with 10CFR2,2.109(9/19/72).
05000244 E
G RECIPIENT ID CODE/NAME PDl-1 LA
'OHNSON,A INTERNAL. FILE CE 1
NR DRCH/HICB NRR/DSSA/SRXB OGC/HDS3 EXTERNAL: NOAC I
COPIES LTTR ENCL RECIPIENT ID CODE/NAME PD1-1 PD NRR/DE/EMCB
'NRR/DSSA/SPLB NUDOCS-ABSTRACT NRC PDR COPIES LTTR ENCL 0
D p
C NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTEl CONTACT THE DOCUMENT CONTROL DESK, ROOM OWFN 5D-5(EXT, 415"2083)
TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEEDI TOTAL NUMBER OF COPIES REQUIRED:
LTTR 12 ENCL
AND 0
ROCHESTER GASANDEIECTRIC CORPORATION ~ B9 FASTAVENUE, ROCHESTER, N. Y Idbf9-0001 ARFA CODE716 Sf6-2700 ROBERT C. MECREDY Vice President Nvciear Operations March 22, 1996 U.S. Nuclear Regulatory Commission Document Control Desk
.Attn:
Allen. R. Johnson Project Directorate I-1 Washington, D.C.
20555
Subject:
Generic Letter (GL) 95-03 dated April 28, 1995 "Circumferential Cracking of Steam Generator Tubes" Response to NRC Request for Additional Information (RAI)
R.
E. Ginna Nuclear Power Plant Docket No. 50-244
References:
(a)
Letter from R.C.
Mecredy (RG&E) to A.R.
Johnson (NRC),
Subject:
Response
to Generic Letter 95-03, dated June 27, 1995 (b)
Letter from A.R. Johnson (NRC) to R.C. Mecredy (RG&E),
Subject:
Request for Additional Information (RAI) Circumferential Cracking of Steam Generator Tubes (TAC No. M92244), dated December 19, 1995.
Dear Mr. Johnson:
RG&E provided its 60-day response to GL 95-03 by letter dated June 27, 1995 (Reference a).
NRC requested additional information relative to our response by letter dated December 19, 1995 (Reference b).
The Reference (b) RAI requested, within 30 days of receipt, detailed information involving seven (7) individual topic areas related to circumferential cracking of the existing and replacement steam generators.
Due to administrative oversight, Reference (b) was not available to our staff to prepare responses until February 28, 1996, therefore, a written response was not submitted within the 30-day allotted time.
Subsequent telephone conversations with NRC staff clarified that additional time would be acceptable, during which we could prepare and submit the necessary information.
Nonetheless, due to time constraints imposed by critical path outage work (outage scheduled to commence on April 1) on the RG&E staff knowledgeable of our Eddy Current Inspection activities, we respectfully must request additional time to prepare and submit responses to Questions 1-4 and 6, which are associated with the existing (old) steam generators.
We will attempt to provide this data by July 1, 1996 following completion of the refueling outage.
9603290i'14r960322 PDR.+'ADOCK 05000244 P
PDR yi)l i
c f
~
~
L
\\
V kj 1, II
The additional information requested by Questions g5 and g7, which are associated with the replacement steam generators, is provided herein.
replacement steam generators prior to startup.
The eddy current baseline examination was performed at Babcock
& Wilcox International (BWI) Cambridge,
- Ontario, Canada in the BWI manufacturing facility.
Examination personnel were from BWI and BWNT (Framatome).
The examination data was acquired with the Zetec MIZ-30 multi frequency acquisition system and stored onto optical disk media.
The Zetec "Eddynet" software was used for both data acquisition and data analysis.
The examinations for "A" steam generator (BWI unit g34),
and "B" steam generator (BWI unit f35) included a
1004 tube end to tube end examination utilizing the Zetec
.620 MULC and.610 MULC bobbin coils.
The data underwent an independent two (2) party analysis review and then a third party resolution analysis process.
The eddy current data was analyzed for: data quality, evidence of wall loss indications, loose parts detection, and any manufacturing anomalies.
The bobbin data was further analyzed with the Zetec profilometry software within the inlet and outlet tubesheet regions for 1004 of the tubes.
This analysis consisted of a single review and a Q.A. review to assure consistency of results.
This analysis identified any hydraulic tubesheet expansions that were out of tolerance or unique.
The baseline also included data acquisition utilizing the Zetec
.610 plus point MRPC (+point.115//36/S80) probe.
Data was acquired in areas with unique indications to establish a
more thorough set of baseline information, such as:
tube expansions beyond the secondary face; tube expansion anomalies within the tubesheet; normal tubesheet expansion transitions; U-bend transitions; and a
cross section of Mechanical Burnish Marks (MBM s), which would include large amplitude indications, and all bobbin indications that measured
>15% thru wall.
These examinations were all in accordance with the applicable acquisition and analysis procedures.
An eddy current bobbin examination is planned for post steam generator installation and prior to plant startup to supplement the baseline examination.
The examination plan is for all periphery tubes in both generators which encompasses an approximate 10<
examination of the tube population.
This examination will be done primarily for loose parts detection associated with any steam generator secondary side work, but we will also do a thorough data analysis consistent with an inservice inspection activity.
uestion analyze the RPC eddy current data at locations susceptible to circumferential cracking during the next steam generator tube inspection.
The replacement steam generators were given baseline inspections as discussed in question g5 which did include RPC (Rotating Probe Coil) utilizing the plus point probe.
The data analysis included the plotting of terrain plots in the areas of unique indications, to further enhance the RPC detection capabilities.
For the Future RPC inspections we plan to employ the same RPC data analysis technique's.
Very truly yours, Robert C. Mecredy NRC54421
~ GAH xc:
Mr. Allen R. Johnson (Mail Stop 14B2)
Project Directorate I-1 Washington, D.C.
20555 U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406 US NRC Ginna Senior Resident, Inspector
f's 0
t
~'0 r