ML18136A205
| ML18136A205 | |
| Person / Time | |
|---|---|
| Site: | Surry  |
| Issue date: | 11/13/1979 |
| From: | Neighbors D Office of Nuclear Reactor Regulation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7911210345 | |
| Download: ML18136A205 (5) | |
Text
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. UNITED STATES NUCLEAR REGULATOR'v COMMISSION.
WASHINGTON, D. C. 20555 NOVEMBER 1 a 19~
Docket No. 50-281 LICENSEE:
VIRGINIA ELECTRI.C AND POWER COMPANY (VEPCO)
FACILITY:
Surry, Unit No. 2
SUBJECT:
SUMMARY
OF MEETING HELD ON OCTOBER 24, 1979 TO REVIEW PI PE STRESS ANALYSES PERFORMED BY EBASCO SERVICES INCORPORATED The subject meeting was held with VEPCO and Ebasco to review the pipe stress analyses and support analyses performed by Ebasco for VEPCO.
A list of attendees is attached (Attachment 1).
All but one of 55 pipe stress problems in Ebasco I s scope iiave ooen re-analyzed.
Of these 55 problems, 30 have been found to be within allowable stresses whereas 69 support modifications were found necessary to bring the 24 pipe problems within allowable stresses.
Due to modifications to temperature and pressure inputs, however, 22 out of the 55 pipe problems are in the process of "updated reanalysis".
The licensee stated that this is being done only for record keeping purposes with no further impact on pipe stresses and supports expected. This is expected to be completed within two weeks.
In the Stone and Webster's scope of 18 pipe problems, only three problems have been reanalyzed and all found within allowables.
The licensee has also identified a total of 822 additional supports to be reevaluated as a result of the pipe stress reanalysis; of these 613 fall in Ebasco's scope whereas 209 supports are to be done by Stone and Webster.
Of the above 613 supports, 260 have been reevaluated and found to be within allowable stresses, whereas 90 other supports have been reevaluated and found to be.above allowable stresses and thus require modifications. Stone and Webster has not started the support reevalu,ation yet.,
The licensee stated that Ebasco will complete reevaluation of all the supports in about three weeks, release all modification information to the site in about four weeks, and finally complete all -modifications in about three weeks after releaise of the information.
Dur1ng the meeting, we reviewed the reanalysis procedures for pipe stre~s and support and found them generally acc:eptabl e.
Specifically, we reviewed five pipe stress problems as well as five support problems which are identified to need modification.
These five pipe stress problems are problems 2508 (RHR), 2602A and 2602b {CCW), 2757 {C&RS), and 2864 (HP Steam Auxiliary Feedwater Pump).
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Meeting Summary for VEPCO NOVEMBER 1 3 1979 The MKS 1s and the corresportding results, including original analysis results, if available, were reviewed and found acceptable.
During the review process, the following staff concer.ns were r~ised and, to.some*
degree, were satisfactorily resolved by the licensee and Ebasco.
. l. Validity of the assumption of*an anchor at heat eichanger to break up the size of the problem.
- 2.
Existence of a valid Ebas*co QA procedure.
- 3.
Existence of a branch line tracking procedure.
The five overstressed supports reviewed were a U-bolt in problem 2540 (Support H-17), rod hanger in problem 2539 (Support H-i), and a restraint in problems 2538, 2541 and 2548 (respectively identified as H-15, H-8, and H-11).
With the exception of the support:in problem*
2539 where a 25 pound uplift force was overlo.oked in the reanalysis (as versus to overstress but no uplift in the original support design), the remaining supports were found to have been adequately modified.
With regard to the QBE pipe reanalysis, as requested by VEPCQ on September 13, 1979, the licensee and Ebasco were informed verbally of the following:
- l. The 25 percent 11 bump factor 11 is considered adequate.
- 2.
The equation used to calculate new QBE level is considered acceptable provided that the variation in QBE level does not exce~d 15 percent. If this range is exceeded, proper justi-ficatfori will have to be provided.
Among the staff 1s concerns which are open items are:
- l. Validity of support stiffeners used in piping reanalysis when, for example, a vertical trunion is welded onto a horizontal wide ti a nge beam.
- 2.
Pertinence of the version of B31.1 Code implemented in CDC NUPIPE program which is used in the Ebasco 1s reanalysis program.
3; Identification of the original loads on sup.port H.:.15 in problem 2538. *
- 4.
Perform pipe stress problem supplied by NRC to verify computer program.
Meeting Summary for VEPCO e
In addition, VEPCO intends to:
.e NOVEMBER 1 3 1979
- l. Review the procedures Ebasco. uses to ass~re that all the proper criteria are being used.
- 2.
Document the revised procedure which assures that all branch lines are accounted for.
- 3.
Assure that QA checks of problems are adequate.
- 4.
Submit a report when the analyses are complete summarizing the modifications required.
Attachment:
List of Attendees cc: w/attachment See next page
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Don Neighbors, Project Manager Operating Reactors Branch #1 Division of Operating Reactors
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NRC J. D. Neighbors W. Russell A. Lee R. Compton ( I&E)
VEPCO C. M. Robinson, Jr.
G. Strickler LIST OF ATTENDEES AT OCTOBER 24, 1979 MEETING ATTACHMENT l EBASCO H. Nelson N. Shah T. Cotter
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Meet1ny Summary for VEPCO
~Docket Files NRC PDR Local POR ORB] Reading NRR Reading H. Denton E. Case D.* Ei senhut R. Tedesco G. Zech B. Grimes
- w. Gammill L. Shao J. Mi 11 er R. Vollmer T. J. Carter A. Schwencer D. Ziemann P. Check G. Lainas *
- o. Crutchfield B. Grimes T. -Ippolito R. Reid V. Noonan
.G. Knighton D. Brinkman*
Project Manager OELD OI&E (3)
- c. Parri sh/P. Kreutzer ACRS (16)
NRC Participants NS-IC TERA Licensee Short Service List
' NOVEMBER 1 3 1979 Mr. Michael W. Maupin
- Hunton and* Wi1 l1ams Post Office Box 1535 Richmond, Virginia 23213 Swem Library College of William and Mary Williamsburg, Virginia 23185
- Donald J *. Burke U. S. Nuclear Regulatory Cammi ssion Region II
- Office of inspection arid Enforcement*
101 Marietta Street, Suite 3100 Atlanta, Georgia 30303