ML20062C479

Safety Eval Supporting Amend 40 & 32 to Lic DPR-31 & DPR-41. Concludes That No Adverse Effects Will Result

ML20062C479
Person / Time
Site:	Turkey Point
Issue date:	10/25/1978
From:	Office of Nuclear Reactor Regulation
To:
Shared Package
ML20062C454	List: ML20062C452 ML20062C472 ML20062C473 ML20062C479
References
NUDOCS 7811090024
Download: ML20062C479 (3)

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NUCLEAR REGULATORY COMMISSION UNITED STATES

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E WASHINGTON, D. C. 20555 i

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I SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION I

j SUPPORTING AMEN 0 MENT NOS.40 AND 32 TO LICENSE NOS. OPR-31 AND DPR-41 I

FLO'1IDA POWER AND LIGHT COMPANY t

TURKEY POINT NUCLEAR GENERATING UNITS NOS. 3 AND 4 2

DOCKET NOS. 50-250 AND 50-251

!O tatroductica By letter dated December 15, 1977, Florida Power and Light Company Ithe licensee) requested amendment of the Technical Specifications appended to Facility Operating License Nos. DPR-31 and DPR-41 for the Turkey Point Plant Unit Nos. 3 and 4 The amendment reduces the maximum pressurizer heatup rate fran 200*F per hour to 100*F per hour.

Backcround In August 1977, Mitsubishi Heavy Industries, Ltd. of Japan noted an inconsistency in the pressurizer heatup rate stated in their Technical Speci fications.

Specification 3.4.9 required a heatup rate of 200*F/hr; Specification 5.7.1, however, recuired a heatup rate of 100*F/hr.

This discrepancy was reported to the Westinghouse Electric Corporation (Westinghouse), who then reviewed their analysis of the pressurizer heatup O

rate and dete=iaed that the correct heatuP rate is 100 F/hr, and that the correct cocidown rate is 200*F/hr; the Technical Specifications for Turkey Point stated that pressurizer heatup and cooldewn rates were 200*F/hr.

Westinghouse then notified the Nuclear Regulatory Commission (the Commission) and the licensee of this problem.

The licensee reported the error as Report-able Occurrences 50-250/77-7 and 50-251/77-7.

The requested amendment would correct the error in the pressurizer heatup rate limit.

Evaluation In designing the pressurizer, Westinghouse perfonned a thennal stress analysis which analyzed the fatigue resulting fran a heatup rate of 100*F/hr and a cool-down rate of 200*F/hr.

This analysis meets the standards of the ASME Code,Section III, which requires that the analysis be b4 sed on a usage factor.

The usage factor represent the fraction of the fatigue life (the total amount amount of stress that a particular component is desianed to handle), with a usage factor of zero implying that no stress has been exerted on the comconent, and a usage factor of one implying that the stress exerted on the complying that the stress exerted on the component is equal to the amount of stress 78//@#z/

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that the camponent is designed to handle.

For any piece of equipment, certain canponents receive more stress than others.

For the pressurizer, this canponent is the surge nozzle, which has i

a usage factor of 0.9 for the design numbers listed above. This usage factor is such that if the heatup and cooldown rates used in the analysis were exceeded more than a few times, the actual usage factor for the surge nozzle would exceeo 1.0, which is not allowable under the ASME Code. Thus, we conclude that reducing the heatup rate limit from 200*F/hr to 100*F/hr is necessary to maintain themal stresses in the pressurizer to allowable levels.

For the same reasons, we further conclude that the cooldown rate limit presently listed in the Technical Specifications is adequate.

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Because the current Technical Specification provision authorized higher rates of pressurizer heatup than the correct limit, the question arose l

as to whether the correct limit of 100*F per hour has been exceeded in i

the past.

Discussions with Westinghouse indicate that this is unlikely.

This is because system capabilities and Technical Specification limits on the rate of reactor coolant system heatup and pressurization effec-i l

tively preclude pressurizer heatup rates in excess of 50*F to 75'F per hour.

Furthemore, the licensee reviewed the pressurizer and heater designs for Turkey Point after being informed of this potential i

problem and found that they are sized for a 55'F per hour heatup rate

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and therefore concluded that the heatup rate never exceeded 100*F per hour.

Accordingly, we concluce that the only action required by the i

licensee is mooification of the Technical Specifications to reduce the l

limiting pressurizer heatup rate of 200*F per hour to 100*F per hour.

O it is our understandins that Westin9nouse is perfomins a review of the stress analyses for canpanents of the reactor coolant pressure l

boundary to assure that no similar inadvertent error appears in any other pSrtion of the applicable Technical Specifications.

This action will be confimed by Westinghouse.

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l Environmental Consideration We have determined that the amendments do not authorize a change in i

effluent types or total amounts nor an increase in power level and will not result in any significant environmental impact.

Having made this i

detemination, we concluded that the amendments involve an action which

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is insignificant from the standpoint of environmental impact and pursuant l

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i to 10 CFR 551.5(d) (4) that an environmental impact statement, or negative declaration and environmental impact appraisal need not be prepared in connection with the issuance of these amendments.

Conclusion l

We have concluded, based on the considerations discussed above, that:

(1) because the amendments do not involve a significant increase in the probability or consequences of accidents previously considered and do not involve a,significant decrease in a safety margin, the amendments do not involve a significant hazards consideration, (2) there is reasonable

({'S assurance that the health and safety of the public will not be endangered by operation in the proposed manner, and (3) such activities will be conducted in compliance with the Commission's regulations and issuance 7

of the amendments will not be inimical to the common defense and security l

or to the health and safety of the public.

Date:

October 25, 1978 l

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