TXX-9259, Forwards Advance FSAR Submittal to Facilitate NRC Review in Area of Thermo-Lag Upgrade to safety-related Conduits.Encl Matl Scheduled to Be Incorporated in FSAR Amend 87 Currently Scheduled for Submittal on 921218
| ML20126C831 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 12/18/1992 |
| From: | William Cahill, John Marshall TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| TXX-92590, NUDOCS 9212230236 | |
| Download: ML20126C831 (3) | |
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- 10CFR50.55a 11/ ELECTRIC December le, 1992 Wi!!Iam J. Cahdl. Jr.
Gnwp \\ kr hevdev U. 5. Nuclear Regulatory Commissinn Atto: Document Control Desk Was*Hngton, DC 20555
SUBJECT:
COMANCHE PEAK STEAM ELECTRIC STATION (CPSES) DOCKET NOS, 50-445 AND 50-446 ADVANCE FSAR SUBMITTAL - THERMO-LAG UPGRADE TO SAFETY RELATED CONDUITS Gentlemen: The attachment to this letter provides an advance CPSES FSAR submittal te facilitate NRC Staff review of the subject area in support of licensing Unit 2. The attachment is organized as follows: 1. A description / justification of each change. 2. A copy of the revised FSAR pages (changes are indicated in the margin by the word " Draft"). The attached-material is scheduled to be incorporated in CPSES FSAR Amendment 87 which is currently scheduled for December 18, 1992. If you have any questions regarding this submittal, please contact Mr. Cert Corbin et (214) 812-8859. Sincerely, William J. Cahill, Jr. By: J. S. Marshall Generic Licensing Manager l CBC/tg Attachment c Mr. J L. h!1hoan, Region IV Mr. 7 A. Bergman. HRR Mr. B. E. Holian, NRR P.esident inspectors CPSES (2) _. m ..:r ; 9212230236 921218 kI .PDR ADOCK 050004-45 9l )
CPSES - FINAL SAFETY ANALYSIS REPORT (FSAR) ATTACHMENT TO AMENDMENT / REVISION 87 Txx-925 90 L DETAILLs DESCRIPTION Page 1 of 2 Profix Page (A1 ameI1!ied) Ergup Descri o_t_l on 3.100-7 3 Documents the use of damping values of A% and 7% SSE for Thermolag upgrade to safety relateu conduits. Addition The use of 4% and 7% damping values for safety related conduits with Thermolag is based on the following: i (1) The structural supports and clamp supports for safety related Train A ana B conduit systems with Thermolag are shcwn to have the characteristics of s bolted structure and are therefore subjected to the Regulatory Guide 1.61 damping values of 4% (OBE) and 7% (SSE) for bolted structures; (2) A number of other nuclear facilities have used 4% and 7% damping values in their evaluations of safety related conduit systems similar to those systems found at CPSES: and, (3) Representative test data, conservatively interpreted, for CPSES Train C conduits and unistrut supports prcvide evidence that 7% damping is achievable. These s results can then be extended to the safety related conduit systams for justifying the use of higher damping values for specific cases. Change Request Wumber
- SA-92-822.
Commitment Register Number : NL-7554 Related SER 3.10 SSER :1 3.10 SER/SSER Impact
- No
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ATTACHMENT t o TXX-92590 CPSES/FSAR IAGE 2 of. The types of cable trays used are: ladder type with or without tray 44 covers and solid bottom type with or without covers. Trays are supported on structural steel frames anchored to the ceilings, walls, or floors, and braced transversely and longitudinally. Under normal conditions of loading and support spacing, trays and 66 their supports may have natural frequencies which are lower than 33 Hz; therefore, they are requireo to sustain amplified accelerations, I and are designed for the peak values of the floor response spectra at the applicable support elevation, unless a frequency analysis is performed to justify the use of lower acceleration values. For the quaiification of trays, maximum equivalent static loads for 66 SSE are determined from the pzaks of floor response spectra curves corresponding to 7% damping, unless a frequency analysis is performed to justify the use of lower acceleration values and are based or,the full mass of the tray (weight of the tray plus cable). Suppliers are required to determine by static testing on representative trays of 44 each type being used, the strength of the trays in each of the three principal directions of load application, and to compare the equivalent static loads in etch direction with the respective strengths of the trays. The results are combined using an interaction formula to account for the simultaneous application of deadloadandearthankeexcitationinthetnreeprincipaldirections,j Supports for the Seismic Category I electrical cable tray and conduit 44 system are designed to resist the gravity and seismic loads imposed on them by the cable trays and/or conduits. The design of the supports ( is generally based on the peak values of the applicable floor response spectra, unless a frequency analysis is performed to justify the use of lower acceleration values. Floor response spectra corresponding 54 to 7% and 4% darpings for the SSE and OBE, respectively are used for the design of cable tray support systems. For the design of conduit supports, floor response spectra corresponding to 3% and 2% dampings 44 for the SSE and OBE, resDectively are used. For Thermolag upgrade to DRAFT safety related conduits, damping values of 4% and 7% for the OBE and SSE are used, consistent wtih Regulatory Guide 1.61 for bolted s uc hres. 3.108-7 Oraft Version I}}