ML19330B755

Final Significant Deficiency Rept Re Incorrectly Specified & Installed Flange Matl,Originally Discussed W/Nrc on 800708. All 304 Stainless Steel Flanges Will Be Removed & Replaced w/316 Stainless Steel Flanges

ML19330B755
Person / Time
Site:	Summer
Issue date:	07/30/1980
From:	Crews E SOUTH CAROLINA ELECTRIC & GAS CO.
To:
References
3.1051, NUDOCS 8008050454
Download: ML19330B755 (3)

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SOUTH CAROLINA ELECTRIC a GAS COMPANY "csr ceases ses res CownstA,Sourn CAnouMA 29288 E. H. Ca rw s. J a.

vms.p.es.cc=r .. Geon t.scurwc t ca.. ... co..r.e.. July 30, 1980 Mr. James P. O'Reilly, Director United States Nuclear Regulatory Commission Region II, Suite 3100 101 Marietta Street, N. W.

Atlanta, GA 30303

Subject:

. Virgil C. Summer Nuclear Station, Unit 1 Docket No. 50-395 Reportable Significant Deficiency

' Incorrectly Specified and Installed Flange Material NE File: 3.1051

Dear Mr. O'Reilly:

On July 8, 1980, Mr. McFarland of NRC Region II in Atlanta, as well as Mr. Mike Heffley (NRC Region II Site Inspector), were notified orally of a reportable significant deficiency.

Upon the submittance of a Start-Up Field Report, it was noted that seven (7) Westinghouse valves had incorrect mating flange material.

These Westinghouse valves allow 300 pound class mating flanges, however, there was a Westinghouse notation that 316 stainless steel flanges be used. Due to an engineering oversight, 304 stainless steel flanges were specifled and subsequently installed.

A " preliminary" stress analysis was performed to es tablish the possible acceptance of the 304 material. The results of the analysis indicated - that code allowable stress values for the flange and bolt materials would not be exceeded. However, since this was not a final stress analysis, and the results were marginal, the use of this 304 material could possibly have led to degraded operation of the RHR, CVCS and SI systems under design basis conditions if the "as built',' systems had varied unconservatively from the design requirements. We are, I

therefore, reporting this as a significant deficiency under 10 CFR 50.55(e). Detailed information is found in Attachment I.

- Since it has been determined to replac the 304 flanges with 316, South Carolina Electric & Gas Company consd er this the final report on this. item. If any questions arise, pleas et s know.

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er" Puly yours, I

kvm E. d. Lrews, Jr.

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}!r. James P. O'Reilly Page 2 July 30, 1980 CC: _. United States' Nuclear Regulatory Conmission Office of Inspection and Enforcement Washingtori, DC 20555 United States Nuclear Regulatory Commission Documant Management Branch

' Washington, DC 20555 1

ATTACHMENT I

1. Identification of Basic Component c!ating flanges for Westinghouse supplied valves.

2. Nature of Defect and Description of Significant Deficiency As a result of an engineering oversight, a notation on the Westinghouse line specification for the 601 piping systems was not repeated in the Gilbert Associates' Pipe Line Specification for Nuclear Safety Class Piping. This Westinghouse notation specifies using 316 stainless steel flanges (#300 Class) for mating the pipe to the Westinghouse supplied valves.

Since this notation was omitted la the engineering specification 304 stainless steel (#300 Class) flanges were installed in the piping subsequently by Southwest Fabricating and Welding Company.

The 304 stainless steel flanges are less in allowable stresses than that of 316 stainless steel. The " preliminary" stress analysis and the calculated loadings indicated that the 304 stainless steel flanges would be acceptable, but is subject to change pending the final stress analysis.

3. Number and Location of Defects SYSTEM VALVE 50. SIZE :UANTITY Residual Heat Removal (RHR) HCV-603A 10" 2 HCV-6033 10" 2 FCV-605A 8" 2 FCV-6053 8" 2 Chemical & Volume Control 8864A 3/4" 1 System (CVCS) 8864B 3/4" 1 Safety Inj ection (SI) 8865 3/4" 1

4. Corrective Action All aforementioned 304 stainless steel flanges will be removed and f replaced with 316 stainless steel flanges.

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