ML15013A236
| ML15013A236 | |
| Person / Time | |
|---|---|
| Site: | Robinson  |
| Issue date: | 12/02/1986 |
| From: | Requa G Office of Nuclear Reactor Regulation |
| To: | Utley E Carolina Power & Light Co |
| References | |
| TAC-62074 NUDOCS 8612080521 | |
| Download: ML15013A236 (4) | |
Text
December 2, 1986 Docket No. 50-261 DISTRIBUTION Docket File N. Thompson NRC PDR G. Requa Local PDR D. Miller Mr. E. E. Utley, Senior Executive Vice President PAD#2 Rdg ACRS (10)
Power Supply and Engineering & Construction LRubenstein Tech Branch Carolina Power & Light Company OELD Gray File Post Office Box 1551 E. Jordan H. Brammer Raleigh, North Carolina 27602 B. Grimes J. Partlow
Dear Mr. Utley:
Subject:
Carolina Power & Light Letter Dated April 24, 1986, "Piping Stress Analysis Damping Valves," H. B. Robinson Steam Electric Plant, Unit No. 2. (TAC No. 62074)
We have reviewed your subject request to use the damping values in ASME Code Case N-411 for current piping modifications and future piping stress analysis. Before we can complete our review, we require the additional information and commitments identified in our enclosure to this letter.
The enclosure was telecopied to your staff earlier this month.
This information request affects fewer than 10 respondents; therefore, OMB clearance is not required under P.L. 96-54.
Sincerely, prighial Signed by Glode Requa, Project Manager PWR Project Directorate #2 Division of PWR Licensing-A Office of Nuclear Reactor Regulation
Enclosure:
As stated cc:
See next page L
PM:PAD P*D:D#2 D
GRequaV'r LRubenstein 1 //
12/-cJJ86 12/>/86 06126080521 861202 PDR ADOCK 05o0261 P
pDR
Mr. E. E. Utley Carolina Power & Liqht Company H. B. Robinson ?
cc:
Thomas A. Raxter, Esquire Mr. Dayne H. Brown, Chief Shaw, Pittman, Potts and Trowbridge Radiation Protection Branch 9300 N Street, N.W.
Division of Facility Services Washinoton, DC
?0037 Department of Human Resources 701 Rarhour Drive Paleigh, North Carolina
?703-2008 Mr.
McCuen Morrell, Chairman Darlington County' Poard of Supervisors Mr. Robert P. Gruher County Courthouse Executive Director Darlington, South Carolina 29535 Public Staff -
NC'IH P.O.
Rox 29520 Mr. H. A. Cole Raleich, North Carolina
?76?6-ns5'1r Special Deputy Attorney General State of North Carolina P.O. Box 629 Raleigh, North Carolina ?7602 Mr. D. E. Hollar Associate General Counsel Carolina Power and Light Company P.O. Box 1551 Raleigh, North Carolina
?760?
U.S. Nuclear Regulatory Commission Resident Inspector's Office H. B. Robinson Steam Electric Plant Route 5, Rox 413 Hartsville, South Carolina 29550 Regional Administrator, Region TI U.S. Nuclear Pequlatory Commission Suite 2900 101 Marietta Street Atlanta, Georgia 3030?
Mr. R. Morgan General Manager H. B. Robinson Steam Electric Plant Post Office Box 7Q0 Hartsville, South Carolina 29550
P CL0SURF PEOUIEST FOR ADDTTTONAL TNFOPMATTON P. R. Robinson, Unit 2 Engineering Rranch, PWP-A In a letter from A. B. Cutter to Director of NR, dated April 24, 1986, the licensee requested staff aDproval to use the damping values in ASME Code Case N-A11 for current Dipino modifications and future riping stress analyses. In addition to the analysis criteria which is presented in the revised Section 3.7.3.?.7.3, "Dynamic Analysis" of the proposed updated FSAR, the staff requires a commitment to the following conditions prior to use o" the newv damping values:
- 1. The dampinq values specified in Code Case N-411 may be used only in those analyses in which current seismic spectra and procedures have been employed.
The 0.1a and O.2q Housner spectrums which are identified in Fiqures
?.5.2-2 and ?.5.2-3 o the H. R. Rohinson, Unit 2 Updated FSAP cannot he considered as "current".
- 2.
For equipment other than pipina, the damping values specified in Regulatory Guide 1.61, "Damping Values for seismic Design of Nuclear Power Plants," should be used.
- 3. These damping values are not appropriate for analvzing the dynamic response of pipino systems using supports designed to dissipate energy by yielding (i.e., the design of which is covered by Code Case N-42n).
- 4.
These damping values are not applicable to piping in which stress corrosion cracking has occurred unless a case-specific evaluation is made and is reviewed by the NPC staff.
- 5. The damping values specified in Code Case N-411 may be used only in analyses which assume an upper bound envelope of the individual response spectra for all support locations to calculate maximum inertial responses of multiply-supported items.
- 6. Where predicted maximum oiping displacements usina Code Case N-411 criteria exceed the current design calculations by an amount qreater than acceptable tolerance levels, a physical verification of the availability of adeouate clearance with adjacent structures, eauipment and components must be performed. For equipment mounted on piping such as valves with extended structures, oroper account must be taken or both rotation and translation in arriving at the predicted maximum displacement at the extreme ends of pipe mounted equipment.
- 7.
Tt must be verified that the operability qualification level of pipe mounted equipment is not exceeded by the predicted response usino Code Case N-411.
- 8. Where the existing design loads of piDinq supports are exceeded by the new loads predicted hv the use of Code Case N-411, it must be verified that the new loads do not exceed the design capacity of the suoports.
- 9.
Tt must be verified that the cumulative effect of the channes of loads on Piping supports that are in turn sunported by a structural element of a buildina, such as walls, slabs, beams and columns, does not exceed the load carryina capacity of the affected structural element.
- 10.
The FSAR and other applicable documents must be amended to identifv the licensee's request for the application of Code Case N-411 and the staFf's approval of the request. The application of Code Case N-411 shall be described in the FSAR and a commitment shall be included in the FSAP to maintain in the licensee's engineerino records a current list and individual files of all pipe stress packages reanaIV7ed using Code Case N-411.
Provide another proposed revision to the H. P. Robinson Unit 2 FSAR Section 3.7.3.2.7.3 incorporating these additional conditions.