ML20070T096

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Forwards Rev 0 to Davis-Besse Analysis & Evaluation of Safety/Relief Valve Discharge Sys Per NRC NUREG-0737, Technical Rept,In Response to Items II.D.1.2 & II.D.1.3
ML20070T096
Person / Time
Site: Davis Besse Cleveland Electric icon.png
Issue date: 02/01/1983
From: Crouse R
TOLEDO EDISON CO.
To: Stolz J
Office of Nuclear Reactor Regulation
Shared Package
ML20070T098 List:
References
RTR-NUREG-0737, RTR-NUREG-737, TASK-2.D.1, TASK-TM 44572, 905, TAC-44572, NUDOCS 8302080198
Download: ML20070T096 (4)


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TOLEDO Docket No. 50-346 IEE31EIC)FW License No. NPF-3 RICHARD P. CROUSE vu prn. cont Serial No. 905 m<s-M19) P59-5221 February 1, 1983 Director of Nuclear Reactor Regulation Attention: Mr. John F. Stolz Operating Reactor Branch No. 4 Division of Operating Reactors United States Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Stolz:

We are attaching three (3) copies of the detailed analysis of the safety /

relief valve discharge system for the Davis-Besse Nucler- ^ aer Station Unit No. 1. This information is being submitted to supp , the NUREG-0737 requested information on EPRI relief and safety valve testing per Item II.D.1.2 and II.D.1.3 for Toledo Edison.

The report indicates that the safety relief valves, PORV and block valve will function properly for all expected operating and accident conditions.

Three supports on the PORV discharge piping are described in the attached report as requiring modifications. The attached February 2, 1983 letter from Teledyne to Toledo Edison describes the magnitude of the concern, which is minimal, and does not require modification to justify continued operation. Toledo Edison will further evaluate any modifications necessary to meet code requirements. No significant system safety concerns are raised by the attachments concerning system operability.

In summary, the PORV valve and the blocking valve in the original position in the valve room will function properly for all expected operating and accident conditions. The FORV meets the standard of NUREG-0737, Item II.D.1. The safety relief valves (2), in the new location mounted on the pressurizer, meet the standards of NUREG-0737 Item II.D.1.

The safety relief valves will function properly under all expected operating and accident conditions.

Very truly yours,

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RPC:LDY:lah i e6 f']gct) attachment cc: DB-1 URC Resident Inspector THE TJLECO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43652 8302000198 830201 PDR ADOCK 05000346 P PDR

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m "RTELEDYNE ENGINEERING SERVICES

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RECEIVED watisau. uassacsusetts 02:54 . i FEB 0 31983 (S' 7> 890-3350 '** i7'o) 324 7508 NUCt. EAR , r^ February 2, 1983 5639-27 Mr. Marvin Foust Toledo Edison Co.

Edison Plaza 300 Madison Avenue Toledo, OH 43652

Subject:

Davis-Besse PORV Line Supports

Reference:

Technical Report TR-5639-2, Rev. O, Davis-Besse Analysis and Evaluation of the Safty/ Relief Valve Discharge System per NRC NUREG-0737, January 1983.

Dear Mr. Foust:

The referenced technical report describes three supports on the PORV discharge system that will require mootfication. This letter is to show the supports are adequate as is for interim operation of the plant with the following explanation of each:

1. Hanger 30-GCC-8-H2 is a Z direction snubber on the PORV discharge elbows. The support has adequate strength and meets code requirements. The recommended change is to move the attachment point, which would provide additional stiffness to the PORV valve support, and prevent an over stress condition in the 2h inch elbow directly upstream of the PORV.

TED has provided information from the material certification of the SA-403 WP316 stainless steel elbow. The yield strength (Sy) is 72.6 ksi and the ultimate strength (Su) is 85.8 ksi, both at room temperature. The ASME Code shows a minimum Sy of 30 ksi at room temperature and 18.5 ksi at 650 F.

U Using the ratio of h (the correction for the 650 F temperature) times 85.8 ksi and 72.6 ksi gives Sy=44.8 ksi and Su=52.9 ksi. The basic stress intensity limits (Sm) used in ASME Section III have the following relationship.

ENGINEERS AND METALLURGISTS I

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"#PTELEDYNE ENGINEERINGSERVICES f

Toleo: Edison Company 5639-27 February 2, 1983 STRESS INTENSITY TABULATED VALUE* Sy Su 1

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Pm Sm hSy fSu Primary Membrane 16.7 ksi 29.3 ksi 17.6 ksi PL 1.5 Sm Sy Su Local Primary 25.1 ksi 44.8 ksi 29.8 ksi Membrane The stress in c estion is PL and the calculated value is 27 ksi for D.W., seismic and blowdown which is greater than the allowable value of 25.1 ksi in the Code, but less than actual material value of Su which is 29.8 ksi. Therefore, the actual material used has an acceptable allowable stress and the elbow is acceptable for interim plant operation.

2. Hanger 30-GCC-8-H5 is a single vertical snubber and hanger 30-GCC-8-H17 is a double vertical strut. The H5 hanger is over stressed and is located between hanger H17 and an anchor.

Most of the load from H5 would be transferred to hanger H17.

Analysis of H17 with the load of H5 added in shows the steel and welds are acceptable but the anchor bolts will not meet the requirements of NRC Bulletin 79-02. The required factor of safety is 4.0 and the actual one is near 3.5. This is judged to be adequate for interim operation of the PORV s system.

  • Appendix I of ASME Code, 1973 Addenda

"RTELEDYNE ENGINEERING SERVICES Toledo Edison Company 5639-27 February 2, 1983 l If you have any questions or would like further clarification, please call me.

Sincerely, TELEDYNE ENGINEERING SERVICES L0 Cm George E. O'Connor Assistant Project Manager GE0/ao Enclosure cc: D.F. Landers (TES)

G.A. Carpenter (TES)

R.H. Howard (TES) 5 b &