ML20247L943
| ML20247L943 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 05/17/1989 |
| From: | Sieber J DUQUESNE LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| IEB-88-011, IEB-88-11, NUDOCS 8906020302 | |
| Download: ML20247L943 (5) | |
Text
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- /
ver Valley Power Staton Shippingport. PA 15077N v335,$Ela,cmop
'412i 843 s2ss May 17, 1989 i
l U.
S._ Nuclear Regulatory Commission Attn:
Document Control Desk Washington, DC 20555 i
Reference:
Beaver Valley Power Station, Unit No. 2 Docket No. 50-412, License No. NPF-73 NRC Bulletin 88-11 Gentlemen:
Attached is a
response to Item 1, subparts a, b, c and d of NRC Bulletin 88-11 " Pressurizer Surge Line Thermal Stratification" which provides the status of actions taken at Beaver Valley Power Station Unit 2
(BV-2) to meet the requirements of the Bulletin.
After completion of our actions for Item 1.d, we will provide a follow-up letter in accordance with Item 3
of the Bulletin's reporting requirements.
If you have any questions concerning this response, please contact my office.
Very truly yours, 4
J.
D. Sieber Vice President Nuclear Group cc:
Mr. J.
Beall, Sr. Resident Inspector Mr. W.
T. Russell, NRC' Region I Administrator Mr.
P. Tam, Sr. Project Manager Director, Safety Evaluation & Control (VEPCO) l
$0hkk DC kg
(
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COMMONWEALTH OF PENNSYLVANIA)
)
SS:
COUNTY OF BEAVER
)
On this
/
_ day of M
, 1989,
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M, a
Notary blic in and for said before me
/
Commonwealth' and County, personally appeared J. D. Sieber, who being duly
- sworn, deposed, and said that (1) he is Vice President of Duquesne
- Light, (2) he is duly authorized to execute and file the foregoing Submittal on behalf of said Company, and (3) the statements set forth in' the Submittal are true and correct to the best of his knowledge, information and belief.
(ddj l $ !W
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NotanalSeal Sheila M. Fattore, Notary Public Shippng; ort Boro, Beaver County My Commssion Erpres Oct 23,1289 l
_ Member,Pennsylvane AssocatonolNotaries I
L
- DUQUESNE LIGHT COMPANY Nuclear Group Beaver Valley Power Station Unit No. 2 Attachment Resoonse to NRC Bulletin 88-11 Item 1.a.
- Licensees are requested to conduct a
visual inspection (ASME,Section XI, VT-3) of the pressurizer surge line-at'the first available cold' shutdown after receipt of this Bulletin which exceeds seven days.
This inspection should determine any gross discernable distress or structural damage in the entire pressurizer surge line, including L.
piping, pipe supports, pipe whip restraints, and anchor bolts.
Resoonse The Beaver Valley Unit 2 (BV-2) pressurizer surge line and related supports were visually examined during the' first refueling outage.
A more' stringent VT-1 examination was performed on the surge line piping rather than the VT-3 examination required by the Bulletin.
The surge line supports were examined to the VT-3 criteria.
No discernable distress or damage was observed during the examinations.
Item 1.b.
Within four months of receipt of this Bulletin, licensees of plants in operation over 10 years (i.e., low power license prior to January 1,
1979) are requested to demonstrate that the pressurizer surge line meets the applicable design codes and other FSAR and regulatory commitments for the licensed life of the
- plant, considering the phenomenon.of thermal stratification and i
thermal striping in the fatigue and stress evaluations.
This may be accomplished by performing a plant specific or generic bounding analysis.
If the latter option is selected, licensees should demonstrate applicability of the referenced generic bounding analysis.
Licensees of plants in operation less than ten years (i.e.,
low power license after January 1, 1979), should complete the foregoing analysis within one year of receipt of this bulletin.
Since any piping distress observed by addressees in performing action 1.a may affect the analysis, the licensee should verify that the bounding analysis remains valid.
If the opportunity to perform the visual inspection in 1.a does not occur within the periods specified in this requested item, incorporation of the results of the visual inspection into the analysis should be performed in a supplemental analysis as appropriate.
l Attachment l'
Responen to NRC Bulletin 88-11
['
' Pag 3 2 1*
l-Item 1.b, continued Where the analysis shows that the surge line does not meet the requirements and licensing commitments stated above for the duration of the
- license, the licensee should submit a
justification for continued operation or bring the plant to cold
- shutdown, as appropriate, and implement Items 1.c and 1.d below to develop a detailed analysis of the surge line.
Response
A plant specific evaluation of the effects of thermal stratification and thermal striping on the BV-2 pressurizer surge line was performed by Westinghouse.
This evaluation, WCAP-12093 " Evaluation of Thermal I
Stratification for the BV-2 Pressurizer Surge Line" and its supplement were submitted to the NRC for review as part of our January 4, 1989 and February 24, 1989 submittals on primary component support snubber elimination.
The evaluation concluded that thermal stratification has a very limited impact on the integrity of the BV-2 pressurizer surge line and that the forty year design life is not impacted.
This evaluation was performed prior to the visual examinations of the surge line and supports required by Item 1.a of the Bulletin.
Since the visual examinations of the surge line and supports did not reveal any discernable distress or da. iage,
WCAP-12093 remains valid and a supplemental analysis is not required.
Item 1.c.
If the analysis in 1.b does not show compliance with the requirements and licensing commitments stated therein for the duration of the operating license, the licensee is requested to obtain plant specific data on thermal stratification, thermal
- striping, and line deflections.
The licensee may choose, for example, either to install i
instruments on the surge line to detect temperature distribution and I
thermal movements or to obtain data through collective efforts, such as from other plants with a similar surge line design.
If the latter options is
- selected, the licensee should demonstrate similarity in geometry and operation.
Response
The evaluation discussed above concludes that the forty year design life is not impacted, therefore, Item 1.c is not applicable to BV-2.
- However, plant specific monitoring data for temperature distribution and deflections of the surge line were collected during hot functional testing and power ascension testing for BV-2.
This data along with thermal striping data from Westinghouse were included in the WCAP-12093 evaluation, which concluded that the forty-year design life is not impacted.
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' Attachment
.ResDonse to NRC Bulletin 88-11 Page 3 Item 1.d.
Based on the applicable plant specific.or referenced
- data, j
licensees-are requested to update their stress and fatigue analyses to ensure compliance with applicable code requirements, incorporating any observations from 1.a above.
The analysis should be completed no later than two years after receipt of this Bulletin.
If a
licensee is unable to show compliance with the applicable design codes and other FSAR and regulatory commitments, the licenses is requested to submit a justification for continued 4
operation and a description of the proposed corrective actions for effecting long term resolution.
Response
WCAP-12093 is a
plant specific evaluation of the effects of thermal stratification on the BV-2 pressurizer surge line.
This evaluation-shows compliance with code requirements for the forty year design life of the plant.
Specifically, ASME III NB-3600 stress equation (9) did not change, stress equations (10) through (14) evaluations were revised to. incorporate the effects of thermal stratification.
The NRC is currently reviewing this evaluation as part of our submittal on primary component support snubber elimination (TAC 71086).
After the NRC review is
- complete, we will update our ASME III Class 1 stress report of record for the pressurizer surge line.
When this effort ic
- complete, we will provide a follow-up letter in accordance with Item 3 of the Bulletin's reporting requirements.
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