ML19256G298
| ML19256G298 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 09/14/1979 |
| From: | Goodwin C PORTLAND GENERAL ELECTRIC CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| Shared Package | |
| ML19256G295 | List: |
| References | |
| IEB-79-04, IEB-79-4, NUDOCS 7912280678 | |
| Download: ML19256G298 (3) | |
Text
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Portland General Electric Company Cr v es Gccar.in.Jr Ass:stant Vce Pres @nt September 14, 1979 Trojan Nuclear Plant Docket 50-344 License hPF-1 Mr. R. H. Engelken, Director Nuclear Regulatory Commission Region V Suite 202, Walnut Creek Plaza 1990 N. California Blvd.
Walnut Creek, CA 94596
Dear Sir:
On March 30, 1979, you transmitted to us IE Bulletin 79-04 concerning use of incorrect weights for Velan valves in piping analyses. On May 1, 1979 we transmitted our preliminary response. Our final response is attached.
Sincerely, 0
/
C. Goodwin, Jr.
Assistant Vice President Thermal Plant Operation and Maintenance CG/LWE/4kk6B16 Attachment
-f c:
Director w/ attach (3) 9 U.S. Nuclear Regulatory Commission 3
Office of Inspection and Enforcement 7
Mr. Lynn Frank, Director w/ attach State of Oregon Department of Energy 1650 342 7912280 m s = swcn wt. eca nw-rn 9w
ATTACIDfENT 1 TROJAN NUCLEAR PLANT RESPONSE TO IE BULLETIN 79-04 NRC Question 1 List all Seismic Category I piping systems (or portions thereof) where 3, 4, or 6 inch diameter Velan swing check valves are installed or are scheduled to be installed.
PGE Response 3, 4, or 6-in.-diameter Velan swing check valves are installed in Seismic Category I piping systems as follows:
a.
Safety Injection System c.
Chemical Volume and Control System d.
Auxiliary Feedwater System e.
Main Steam System (supply to auxiliary feed pump turbine driver) f.
Makeup Water Treatment System (Containment isolation).
URC Question'2 Verify for all those systems identified in Item 1 above that correct check valve weights were used in the piping analysis.
Explain how and when the correct valve weights were determined.
PCE Response Velan has informed us that the weights of all valves purchased directly by PCE are acceptable (accurate within 15 percent) as listed on the engineering drawings used by our Architect-Engineer, Bechtel, in their piping analyses. The weights indicated by Velan on their drawings were determineo by calculation.
Our Nuclear Steam Supply System supplier, Westinghouse, has inforced us that acceptable valve weights were used in their piping analyses.
NRC Question 3 If incorrect valve weights were used, explain what actions have been taken or are planned to re-evaluate the piping systems affected.
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PGE Response One 6-in. valve in the Auxiliary Feedwater System was found to have been analyzed with a weight approximately 7 percent below that shown on the engineering drawing. The affected portion of the Auxiliary Feedwater System was reanalyzed assuming 115 percent of the valve weight shown on the engi-neering drawing. The analysis showed both pipe stresses and hanger loads to be within code allowables.
NRC Question 4 Specify for a21 the affected systems identified in Item 1 whether modifications were or are required to the piping systems or their supports because of changes in valve weight. Also, include the basis for this determination. For those systems in which the actual valve weight is greater than the design weight provide a summary of stresses and loads and their allowable limics for the piping and its supports.
PGE Response No modifications were required or are planned.
NRC Question 5 Identify the analytical technique including identification of any computer codes used to determine the stresses indicated in Item 4.
PCE Response The analytical technique assumed a flexible piping system per Section 3.7.3.3.2 of the Trojan FSAR.
The reanalysis was done using computer program ME 101.
1650 344 4kk6B20