ML040770141

Draft Information Report SG ISI Report - Attachment 4

ML040770141
Person / Time
Site:	Arkansas Nuclear
Issue date:	02/05/2004
From:	Sharon Bennett Entergy Operations
To:	Alexion T NRC/NRR/DLPM/LPD4
Alexion T W, NRR/DLPM, 415-1326
Shared Package
ML040830346	List: ML040770122 ML040770130 ML040770135 ML040770141 ML040770147 ML040770152 ML040770155 ML040770163 ML040770168 ML040770177 ML040770190 ML040770210 ML040830326
References
Download: ML040770141 (3)

Text

! nomas AIexLin -_r-espornse to tmmeu Myurpny Gesil on mIvj- I ou ri epon - rage iI From: 'BENNETT, STEVE A <SBENNE2@entergy.com>

To: Tom Alexion <twa~nrc.gov>

Date: 2/5/04 11:OOAM

Subject:

Response to Emmett Murphy RAI on ANO-1 SG ISI Report Tom, See response to Emmett's RAI below. Let me know if there is needed followup discussion.

5. Provide summary description of how the 1.87 gpm leak rate estimate was determined for LBLOCA. This should include the following information:

a. Does this estimate consider leakage from flaws other than circumferential cracks?

Response: A small amount of leakage was assigned to repair products for 1R1 7. That is the only other leakage assigned besides circumferential flaws.

The leakage values assigned to flaws are in accordance with the ANO-1 Safety Evaluation Report dated March 28, 2001 which states:

Determination of the best-estimate total leakage that would result from an analysis of the limiting LBLOCA based on circumferential cracking in the original tube-to-tubesheet rolls, tuberFQtorF:tubesheet reroll repairs, and heat affected zones of seal welds as found during each inspection.

b. Brief description of method used to calculate leakage for circumferential cracks in the original roll or heat affected zone adjacent to the tube-to-tubesheet seal weld if no reroll is present.

Response: The reported leakage associated with the rolled joint or the heat affected zone is the calculated leakage through the rolled joint as determined by loading and predicted dilations for LBLOCA for that specific radial location (ratio added for LBLOCA loads). The leakage for a specific flaw is determined by the calculating the stress on the flaw, determining the percent degraded area (PDA) of the flaw and assigning leakage.

c. Brief description of method used to calculate leakage for circumferential cracks at or below lower transition of original roll if no reroll is present.

Response: The leakage is determined by sizing the flaw and determining which section of the flaw could leak without taking any credit for rolled area.

The leakage is determined by taking the lesser of the leakage associated

inomas ~~eIorI?91 -_ 10 ~r-MMLU MujrpflY 5poLs M on mtvu-Ii zI~I 1-lepon-q'gg with the actual flaw and the leakage through the annulus.

d. Brief description of method used to calculate leakage for circumferential cracks at reroll repair.

Response: A reroll length as short 0.86FQY' has been leak tested by Framatome under operational and accident conditions. This leakage is applied if the flaw has moved into the heel transition (outboard or non-pressure boundary).

Again, depending upon the radial distance of tube with the flaw, a leak rate is assigned through the reroll joint or the leak associated with the actual flaw whichever is less. No circumferential cracks were found in rerolls during 1R1 7.

e. Brief description of method used to calculate leakage for circumferential cracks inboard of reroll repair.

Response: The leakage isdetermined by sizing the flaw and determining which section of the flaw could leak without taking any credit for rolled area.

Again, annulus leakage was assigned as discussed in item rQ~crQy' above.

f. Brief description of method used to calculate leakage for circumferential cracks outboard of reroll repair. Are the portions of tubing outboard of reroll repairs subject to inspection?

Response: Yes the outboard reroll is Inspected for Circ cracking. As discussed above, the leakage assigned is the leakage through the reroll joint or the leakage through the flaw, whichever is less.

Steve Bennett NSA - Licensing 479-858-4626 Pager: 479-890-3323 CC: CC:

'JONES, ROCKY L <RJONES4 @entergy.com>

L;AVWINUUVVb\I tMn\WJUUUU 1.1M-MM rage 1 Mail Envelope Properties (40226884.6EB: 11: 63211)

Subject:

Response to Emmett Murphy RAI on ANO-1 SG ISI Report Creation Date: 2/5/04 10:57AM From: "BENNETT, STEVE A" <SBENNE2@entergy.com>

Created By: SBENNE2@entergy.com Recipients nrc.gov owf4_po.OWFNDO TWA (Thomas Alexion) entergy.com RJONES4 CC (JONES, ROCKY L)

Post Office Route owf4_po.OWFN_DO nrc.gov entergy.com Files Size Date & Time MESSAGE 3477 02/05/04 10:57AM Part.001 14308 Mime.822 20579 Options Expiration Date: None Priority: Standard Reply Requested: No Return Notification: None Concealed

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