ML20202C587

Proposed Tech Specs Re Reactor Coolant Pump Flywheel Insps & Loop Flow Straightener Insps

ML20202C587
Person / Time
Site:	North Anna
Issue date:	02/03/1998
From:	VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML20202C567	List: ML20202C562 ML20202C587
References
NUDOCS 9802120284
Download: ML20202C587 (8)

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4 ATTACHMENT 2 PROPOSED TECHNICAL SPECIFICATIONS CH ANGES VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA UNITS 1 AND 2 ej21go po $ $ 3 e

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NORTH ANNA UNIT 1

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i REACTOR COOLANT SYSTEM SURVEILLANCE REQUIREMENTS - _ ---. _ -- . . -_ - -

- 4.4.10.1.1 _In addition to the requirements of Specification 4.0.5, the Reactor Coolant pump flywhccis shall be inspected once every 10 years by a qualified inplace UT examination over the-volume from the inner bore of the flywheel to the circle of one half the outer radius or a surface examination (MT and/or PT) of exposed surfaces defined by the volume of disassembled 1 _

flywheels.

'4.4.10.1.2 In addition to the requirements of Specification 4.0.5, at least one third of the main member to main member welds, joining A572 material, in the steam generator supports, shall be visualiy examined during each 40 month inspection interval.

NORTH-ANNA - UNIT 1 - 3/4434 Amendment No. 68

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NORTH ANNA UNIT 2 s

4 REACTOR CQOLANT SYSTEhi 3/4.4.10 STRUCTURAL INTEGRITY AShili. CODE CLASS 1. 2 & 3 COhiPONENTS LIMITING CONDITION FOR OPERATION 3/4.10.1 The structural integrity of ASME Code Class 1,2 and 3 components shall be maintained in accordance with Specification 4.4.10.1.

APPLICABil_ITY: ALL MODES.

1 AcrlON:

a. With the structuralintegrity of any ASME Code Class I component (s) not conforming to the above requirements, restore the structural integrity of the affected component (s) to within its limit or isolate the affected component (s) prior to increasing the Reactor Coolant System temperature more than 50 F above the minimum temperature required i by NDT considerations.

b. With the structural integrity of any ASME Code Class 2 component (s) not conforming j to the above requirements, restore the stmetural integrity of the affected component (s) to within its limit or isolate the affected component (s) prior to increasing the Reactor Coolant System temperature above 200 F.

c. With the structuralintegrity of any ASME Code Class 3 component (s) not conforming to the above requirements, restore the structuralintegrity of the affected component (s) to within its limit or isolate the affected component (s) from service,

d. The provisions of Specification 3.0.4 are not applicable.

SURVEILLANCE REQUIREMENTS 4.4.10.1.1 In addition to the requirements of Specification 4.0.5, the Reactor Coolant pump flywheels shall be inspected once every 10 years by a qualified inplace UT examinrkn over the volume from the inner bore of the flywheel to the circle of one half the outer radius or a surface examination (MT and/or PT) of exposed surfaces defined by the volume of disassembled flywheels.

4.4.10.1.2 In addition to the requirements of Specification 4.0.5, at least one third of the main member to main member welds, joining A572 material,in .he steam generator supports, shall be visually examined during each 40 month inspection interal.

NORTil ANNA - UNIT 2 3/4 4-32 Amendment No. 40

4 ATTACHMENT 3 SIGNIFICANT HAZARDS CONSIDERATION VIRGINIA ELECTRIC AND POWER COMPANY NORTH ANNA UNITS 1 AND 2

, SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION Virginia Electric and Power Company has reviewed the requirements of 10 CFR 50.92 as they relate to the proposed changes for the North Anna Units 1 and 2

} and determined that a significant hazards consideration is not involved. The proposed changes will allow for the elimination of the inspection requkements for the flow straighteners, and for the reduction in inspection requirements for the reactor coolant pump flywheels as granted by the NRC and supported by WCAP-14535A. These changes will continue to verify the reactor coolant system structuralintegrity.

Reactor coolant pump motor flywheels have been subjected to an augmentad inspection program that satisfies the requirements of Regulatory Position C 4.b of Regulatory Guide 1.14, Revision 1, " Reactor Coolant Pump Flywheel Integrity" since 1979. Regulatory Guide 1.14, prepared in response to a concem over overspeed of the reactor coolant pump and its potential for failure, describes the acceptable method to ensure reactor coolant pump flywheel integrity. These inspections include an in place volumetric ultrasonic (UT) examination of the areas of higher stress concentration at the bore and keyway overy 3 years, and a suriaco examination of all exposed surfaces and complete UT volumetric examination overy 10 years.

Operating power plants have also been inspecting their reactor coolant pump flywheels for over 20 years whereby no flaws have been identified that affect flywheel integrity. This inspection record, plus the concems over inspection costs and personnel radiation exposure prompted Westinghouse Energy Systems to prepare WCAP 14535 to demonstrate through fracture mechanics analysis that flywhool inspections can be eliminated without impairing plant safety. Therefore, Westinghouse Energy Systems report WCAP 14535A,

" Topical Report on Reactor Coolant Pump Flywheel inspection Elimination" has been prepared, reviewed, evaluated, and approved by the NRC to quantify the effects for the elimination of flywheelinspections.

WCAP 14535A provides the technical basis for eliminating the augmented inspection of the reactor coolant pump flywheels and applies to all flywheels manufactured by Westinghouse. However, the NRC accepted the technical arguments presented in the report but only granted partial relief from the reactor coolant pump motor flywheel inspection requirements.

Additionally, in May and June of 1982, during an extended outage for Unit 1, the results of an augmented UT examination disclosed indications in all the flow splitters had grown since the last outago except one. During August and September 1982, the flow splitter plates were removed from Unit 1. The remaining stub ends were ultrasonically examined during the next four refueling outages as required by NRC Safety Evaluation Report transmitted to Virginia Electric and Power Company on December 6,1982. With the removal of the Page 1 of 3

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flow straightonors and the completion of the required examinations, the augment 6d inspection requirements can be eliminated.

The oporation and structuralintegrity cf the reactor coolant system are not being changed. The proposed changes provide augmented inspection requirements that have bou reviewed and recommended by the NRC in their Safety Evaluation Report, " Safety Evaluation by the Offico of Nuclear Reactor Regulation, Topical Report on Roactor Coolant Pump Flywheel inspection Elimination." In support of this conclusion, the following analysos is provided.

a) The elimination of the inspection requirements for the flow straighteners, and the reduction of the inspection requirements for the reac'or coolant pump flywheels as granted by the NRC and supported by WCAP 14535A do not significantly increase the probability of an accident previously evaluated in the safety analysis report. The surveillance frequency changes for the reactor coolant pump flywheels are based upon the technical basis of the Westinghouse Energy Systems Topical Report WCAP 14535A. The results of WCAP 14535A have been reviewed, ovaluated, and accepted for referencing in licenso applications by the NRC in their lotter entitled

" Acceptance for Referencing of Topleal Report WCAP-14535. Topical Report on Reactor Coolant Pump Flywheel Inspection Elimination" dated September 12,1996.

The proposed surveillanco (inspection) requirements only reduce the inspection frequency for the reactor coolant pump flywheels und eliminate the inspection requirements for the flow straightners. There is no change in the method of plant operation or system design.

Therefore, the proposed changes do not increase the probability of occurrence or the consequences of any previously analyzed accident.

b) The proposed changes for the ollmination of the inspection requirements for the flow straighteners, and for the reduction in inspection requirements for the reactor coolant pump flywheels as granted by the NRC and supported by WCAP 14535A do not create the possibility of an accident or malfunction of a different type than any evalutM previously in the safety analysis report.

The proposed surveillance (inspection) requirements only reduce the inspection fren,uency for the reactor coolant pump flywheels and eliminate the inspection requirements for the flow straightners in Unit

1. There is no change in the method of plant operation or system design. Therefore, there are no new or different kinds of accident or malfunction from any accidents previously evaluated.

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, c) The proposed changes for tho elimination of the inspection toquirements f6r the flow straighteners, and for the reduction in inspection requirements for the reactor coolant pump flywheels as granted by the NRC and supported by WCAP 14535A do not Impact the accident analysis assumptions or the basis of any Technical Specification. The revised inspection requirements only reduce the examination frequency for the reactor coolant pump flywheels and eliminate the inspection requirements for the flow straightner in Unit 1. Therefore, the proposed changes in surveillance (inspection) frequency do not result in a significant reduction in the margin of safety.

This analysis demonstratos that the proposed amendment to The North Anna Unit 1 and 2 Technical Specifications does not involve a significant increase in the probability or consequences of a previously evaluated accident, doos not create the possibility of a new or different kind of accident and does not involvo a significant reduction in a margin of safety.

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