ML20024A438

Interim Deficiency Rept NY-QA-5 Re Main Steam & Feedwater Penetration Anchor Stress Analyses.Initially Reported on 830426.Engineering Procedure Revised & Analyses Performed. Final Rept Expected by 830729

ML20024A438
Person / Time
Site:	Satsop
Issue date:	06/09/1983
From:	Leddick R WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
10CFR-050.55E, 10CFR-50.55E, GO3-83-466, NY-QA-5, NUDOCS 8306170296
Download: ML20024A438 (3)

Text

e, - 70 g Washington Public Power Supply System IP g Box 1223 Elma, Washington 98541 (206)482-4428 A Docket No. 50-508 @p */

49 June 9, 1983 G03-83-466 U. S. Nuclear Regulatory Commission, Region V Office of Inspection and Enforcement 1450 Maria Lane, Suite 260 Walnut Creek, California 94596-5368 Attention: Mr. D. M. Sternberg, Chief Reactor Projects Branch No. 1

Subject:

POTENTIAL 10CFR50.55(e) DEFICIENCY MAIN STEAM AND FEEDWATER PENETRATION ANCHORS (D/N N0. NY-QA-5)

On April 26, 1983 the Supply System notified your office of a potential 10CFR50.55(e) deficiency concerning the subject condition. Due to the complexity of the required engineering analysis, a determination of safety significarce cannot be made at this time. Attached is a Supply System approved Interim Report that describes the problem and provides a proposed resolution.

It is anticipated that a final report will be provided to your office

, by July 29, 1983. Should you have any questions or desire further information, please contact me directly.

l Q-

! R. S. Leddick (760)

Program Director, WNP-3 DRC:nj Attachments cc: J. Adams - NESCO D. Smithpeter - BPA Ebasco - New York WNP-3 Files - Richland R. D. Hill - Puget Sound Power & Light Company P. Inman - Washington Water Power ~ Company B. D. Withers - Portland General Electric Company L. D. Weislogel - Pacific Power & Light Company 8306170296 830609 PDR ADOCK 05000508 PDR S

ff47

h Attachment to: Letter, G03-83-466, dated June 9, 1983 WASHINGTON NUCLEAR PROJECT NO. 3 (DOCKET NO. 50-508)

POTENTIAL 10CFR50.55(e) DEFICIENCY INTERIM REPORT MAIN STEAM AND FEEDWATER PENETRATION ANCHORS (D/N NO. NY-QA-5)

Description of Deficiency The stress analyses of the Main Steam and Feedwater lines include an anchor point at the outboard er.d of the containment penetrations.

It is assumed, per Ebasco practice, that the anchoring structure provides a gap (between the flued head trunnion and structural element) of 1/16 inch (maximum). However, during investigation of an as-built discrepancy, it was found that 1/4 inch gaps were provided as specified on two Ebasco drawings. Further investigation disclosed that the Ebasco Civil Group had provided the 1/4 inch gap in order to facilitate installation, but had not obtained approval for this gap magnitude from the Stress Analysis Group. These larger gaps are considered a potential problem because the additional clearances in the anchoring structure may allow stresses in the affected piping to exceed allowable levels.

Corrective Actions The following actions have been/arebeing taken to resolve the problem:

1) Currently, the Ebasco Applied Physics and Applied Mechanics Departments are conducting sample analyses incorporating the 1/4 inch gaps in the models for seismic and pipe rupture calculations. To date, many of the required runs have been completed.

2) A check will be made of pipe stress levels, loading on the anchor and loading on adjacent restraints, to assure satisfaction of all criteria. If all criteria are satisfied, the design gap of 1/4 inch will remain. If the criteria cannot be satisfied, the restraints will be modified to reduce the gaps.

3) An Engineering hold (via a DCN) was placed on the structure pending the results of the analyses described above.

4) To preclude recurrence, the Ebasco Civil Design Group is working to the applicable Engineering Procedure which sets forth the methods to be followed for selecting and documenting design inputs for nuclear power plants.

5) Ebasco will investigate to assure similar problems, concerning design inputs, have not occurred.

.e .

POTENTIAL 10CFR50.55(e) DEFICIENCY INTERIM REPORT MAIN STEAM AND FEEDWATER PENETRATION ANCHORS (D/N NO. NY-QA-5)

Page 2 Reason Why The Final Report Will Be Delayed In order to determine if the 1/4 inch gap is acceptable, additional analyses must be performed. Due to the complexity of the analysis techniques being contemplated, further time is required for its completion. Therefore, a final report will be provided by July 29, 1983.

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