ML20071P989

Submits Info Re SER Outstanding Issue 6 (Section 3.9.2), Steady State Vibration Acceptance Criteria for Balance-of- Plant Piping. Proposed Stress Levels Acceptable for steady-state Vibration

ML20071P989
Person / Time
Site:	Clinton
Issue date:	12/10/1982
From:	Wuller G ILLINOIS POWER CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
References
U-0584, U-584, NUDOCS 8212290179
Download: ML20071P989 (2)

Text

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U-0584

/LLINDIS POWER COMPANY g L30-82(12-10)-6 "p 500 south 27TH STREET, DECATUR, ILLINOIS 62525 December 10, 1982 Mr. A. Schwencer Licensing Branch No. 2 Division of Licensing Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Schwencer:

Clinton Power Station Unit 1 Docket No. 50-461

References:

1) IP Letter U-0477, dated 5/10/82, from G. E. Wuller to J. R. Miller

2) NRC Letter, dated 6/29/82 from R. E. Carter to G. E. Wuller

3) IP Letter U-0543, dated 9/15/82, from G. E. Wuller to C. O. Thomas

4) NRC Letter, dated 11/24/82, from C. O. Thomas to G. E. Wuller This letter provides information regarding CPS-SER Out-standing Issue No. 6 on " Steady State Vibration Acceptance Criteria for BOP Piping", (Section 3.9.2).

The reference letter no. 1 transmitted to the Staff the draft of the ASME Standard, OM-3, showing ASME Committee approval of the 80% endurance limit (Sa) from Appendix I of the ASME Code on steady-state vibration acceptance criteria for BOP Piping. Reference letter no. 2 stated that the Staff required further technical justification for use of this c: tteria.

Reference Letter No. 3 provided technical justification fo r the use of the ASME criteria if an additional factor of safety of 1.3 is applied when detailed evaluation methods are used to determine the vibratory stresses. It was IP's position that when simplified evaluation methods are used, there is sufficient inherent conservatism in these methods to account for the factor of safety. Reference Letter No. 4 stated that the Staff does not accept the use of a higher stress allowable (i.e. 10,000 psi Yor carbon steel with UTS 6 80Ksi) based upon the inherent conservatisms in the methodology.

8212290179 821210 PDR ADOCK 05000461 E PDR

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i U-0584 i L30-82(12-10)-6 i December 10, 1982 (

Page 2 It is IP's position that the proposed stress levels are acceptable for steady-state vibration (i.e. 7,690 psi for car-bon steel with UTSt 80ksi and 12,000 psi for stainless steel),

which is consistent with the NRC Staff's position. To ensure  ;

an equivalent level of conservatism, regardless of the metho-dology involved in evaluating the measured vibrations, IP proposes to apply the same 1.3 factor of safety to the simpli- .

fled methods. This results in a consistent stress level  !

acceptance criteria, regardless of the methodology. I IP believes that the above information provides adequate justification for closing this issue. IP intends to incorpo-rate this information into the CPS-FSAR in the near future.

If you should have any further concerns, we stand ready to meet with your staff at their earliest convenience so that this issue can be closed out as expeditiously as possible.

Sincerely, L. t

) - v--

G. E. Wuller Supervisor-Licensing Nuclear Station Engineering TLR/lt cc: H. Abelson, NRC Clinton Project Manager H. H. Livermore, NRC Resident Inspector Illinois Department of Nuclear Safety