ML20071C133

Forwards Updated Page to PSAR Chapter 4.4,design Bases Section.Info Concerns Primary Sodium Gas Entrainment & Assembly Flow Blockage Criteria.Page Will Be Submitted W/ Next PSAR Amend

ML20071C133
Person / Time
Site:	Clinch River
Issue date:	02/28/1983
From:	Longenecker J ENERGY, DEPT. OF, CLINCH RIVER BREEDER REACTOR PLANT
To:	Grace J Office of Nuclear Reactor Regulation
References
HQ:S:83:228, NUDOCS 8303010505
Download: ML20071C133 (2)

Text

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Department of Energy Washington, D.C. 20545

' Docket-No. 50-537 HQ:S:83:228 BB3 FEB 20 di Dr. J. Nelson Grace, Director CRBR Program Office Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission .

Washington, D.C. 20555

Dear Dr. Grace:

ADDITIONAL INFORMATION REGARDING PRELIMINARY SAFETY ANALYSIS REPORT (PSAR)

CHAPTER 4.4 Enclosed is an update to the Clinch River Breeder Reactor Plant PSAR Chapter 4.4, design bases section. As previously discussed with Mr. Tom King of your staff, the enclosed page provides information on primary sodium gas entrainment and assembly flow blockage criteria. This

. page will be included in the next amendment to the PSAR.

Any questions concerning this submittal can be directed to Mr. K.' Peterman (FTS 626-6186) of the Project Office Oak Ridge staff. ;A Sincerely, U

Jdhn R. LongeneGer Acting Director, Office of Breeder Demonstration Projects Office of Nuclear Energy Enclosure cc: Service List

Standard Distribution Licensing Distribution 9303010505 G30228 DR ADOCK 05000 SSf

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Enclosure

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( l 13. The. control assemblies flow rate will be such as to assure adequate margin against flotation in case the driveline becomes accidentally disconnected (see Section 4.2.3.1.3) .

l 14. Assemblies orificing will be designed to be cor.sistent with the requirement that the lower shield in the f uel, blanket and control assemblies will have suf ficient solid volume fraction to limit  !

radiation damage to the core support structure and to assure its I prescribed lifetime.

l l- 15. The thermal-hydraulic design of the control assemblles wilI be such as to satisfy the scram insertion requirements during the reactor l if etime (see Section 4.2.3.1.3) .

, l 16. The sodium temperature shall be less than its bolling point during ncemal operation and anticipated and unlikely transient conditions.

l 17. The reactor will meet the aforementioned design bases operating over a range of power and flow rates, including pcwer ranges and flow l

variations, from 0 to 100% of nominal conditions.

l 18. Adequate design margins (see Section 4.4.3.2) wilI be provided to account for design, fabrication, operational uncertainties and tolerances to ensure meeting the aforementioned limitations. The semi-statistical hot channel factors approach wilI be adopted in combining Individual fuel, blanket and control assembly I uncertainties.

l 19. As explained in Section 4.4.3.3.1, plant T&H design conditions are considered In performance evaluntions of permanent piant com-ponents(+), e.g., vessel, Internals, heat exchangers. Therefore, these conditions shall be considered in evaluation of items 7 through 4

10,16 through 18. On the other hand, plant expected operating conditions are adopted in steady state perf ormance and desip evaluntions of replaceable components such as the reactor assembiles.

Therefore, plant expected operating conditions shall be considered In l evaluation of items 1 through 6,11 through 15,17 and 18.

20. The design shall prevent gas entrainment sufficient to cause significant heat transfer or reactivity changes in the core.

21. The design shall provide features to minimize the potential for flow blockage of incore assemblies, i

t 4.4-3

) Amend. 69 j July 1982

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