ML20044A296

Submits Revised Response to NRC Bulletin 89-002 Re safety- Related Swing Check Valves to Be Installed on Emergency Diesel Generator.Bolts Will Not Be Replaced Because Valves W/Original Internal Bolts Meet Requirements of Bulletin

ML20044A296
Person / Time
Site:	Peach Bottom
Issue date:	06/21/1990
From:	Hunger G PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
IEB-89-002, IEB-89-2, NUDOCS 9006280311
Download: ML20044A296 (2)

Text

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3- NRCB No. 89 #

PHILADELPHIA ELECTRIC COMPANY NUCLEAR GROUP HEADQUARTERS 955 65 CHESTERBROOK BLVD.  ;

a WAYNE, PA 19087 5691-(215) 640 6000 I

June 21, 1990 i l

Docket Nos. .50-277 1

'50-278 l 1

License Nos. DPR-44 j DPR-56 l I

U.S. Nuclear Regulatory Commission i Attn: Document-Control Desk j Washington, DC 20555

Subject:

Peach Bottom Atomic Power Station, Units 2 and 3 Revised Response to NRC Bulletin No. 89-02, " Stress a Corrosion Cracking of High-Hardness Type 410 Stainless Steel Internal Preloaded Bolting in Anchor Darling i Model-S350W Swing Check Valves or Valves of Similar.  !

'Desigr." ,

Gentlemen:

L 1 This letter is being submittedLto revise our response to L .NRC Bulletin No. 89-02,~" Stress Corrosion Cracking of ,.

High-Hardness Type 410 Stainless Steel Internal Preloaded Bolting E

E in Anchor Darling Model S350W Swing Check Valves or Valves of L Similar Design," dated July 19, 1989, for Peach Bottom Atomic-Power Station (PBAPS), Units 2 and 3. _Our response to Bulletin No.'89-02 for both PBAPS, Units 2 and.3, and Limerick Generating, L Station.(LGS), Units 1 and 2, was submitted by our letter dated '

p January 16, 1990.

y^ In our January 16, 1990 response to.this Bulletin for -

PBAPS, Units 2 and 3, we identified eight (8) safety-related swing check valves that were to be installed on the Emergency Diesel Generator - Diesel Air Start-Receiver Tank outlets during a modification scheduled-for implementation in mid-1990. The 9006260311 900621

.PDR ADOCK 05000277

/'t v h Q- PDC fr  ;

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c. U.S. Nuclc2r R;gulatory Commiesion JunD 21, 1990 Document control Desk Pace 2 January 16, 1990 letter stated that these valves would be returned to the manufacturer and the Type 410 stainless steel bolts would be replaced with bolts of a suitable material prior to installation on the Diesel Air Start Receiver Tank outlets.

However, after further evaluation regarding the feasibility of returning the valves to the manufacturer, we chose to perform hardness tests on all of the subject bolts in each of the eight (8) valves as specified in the " Requested Actions" identified in Bulletin No. 89-02. The hardness test results fcr the bolts in each of the valves had Rockwell hardness values well below the acceptable hardness value stipulated in the Bulletin-(i.e.,

hardness number Rc 26). Therefore, the bolts will not be replaced as originally stated in our January 16, 1990 response to this Bulletin because the valves with the original internal bolts <

meet the requirements of Bulletin No. 89-02.

If you have any questions, or require additional information, please do not hesitate to contact us.

Si cerely yours,

b. , 1.

G. A. Hunge , Jr.

Manager Licensing Section Nuclear Engineering and Services cc: T. T. Martin, Administrator, Region I, USNRC J. J. Lyash,'USNRC Senior Resident Inspector, PBAPS L