ML20210K383

Forwards Responses to IE Bulletin 85-003 Re motor-operated Valves,Including Description of Program Required to Accomplish Items (b)-(d) & Justification of Extended Completion Schedule

ML20210K383
Person / Time
Site:	Farley
Issue date:	09/18/1986
From:	Mcdonald R ALABAMA POWER CO.
To:	Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20210K387	List: ML20210K383 ML20210K417 ML20210K450
References
IEB-85-003, IEB-85-3, NUDOCS 8610010422
Download: ML20210K383 (13)

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• C , Alz.btma Power CompIny r 600 North 16th Street Post Oi'!ce Box 2641 n Dirmingham, Alabama 35291 ef7 r, Telephone 205 783-6090 0-o R. P. Mcdonald h[

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o % 7 [g*"' September 18, 1986 Alabam5 r i,e sa.vvm ea t? c u s:.

U. S. Nuclear Regulatory Comission Region II, Suite 2900 101 Marietta Street N. W.

Atlanta, GA 30323 Attention: Dr. J. N. Grace Gentlemen:

Joseph M. Farley Nuclear Plant - Units 1 and 2 1.E. Bulletin No. 85-03 Motor-Operated Yalve Common Mode Failures During Plant Transients Due to Improper Switch Settings I.E. Bulletin No. 85-03 requested that all nuclear power reactor facilities develop and implerrent a program to ensure that switch settings on certain safety-related motor-operated valves (MOVs) are selected, set and maintained correctly. By letter dated May 14, 1986, Alabama Power Company committed in response to this bulletin to provide by September 18, 1986 the results of item (a) and the program and schedule to accomplish items (b) through (d).

Attachment 1 describes the program that is required to accomplish items (b) through (d) and justifies the extended schedule for completion of the Farley Nuclear Plant MV Evaluation Program. As required by item (a), Attachments 2 and 3 provide 4 summary of the design basis review for the operation of each

, valve in::luding the maximum differential pressure expected during both valve l opening and closing. Attachment 2 addresses the identified MOVs in the high l pressure coolant injection system, and Attachment 3 addresses the identified MOVs in the auxiliary feedwater system. The required schedule is provided in a preliminary form as Attachment 4.

If you have any questions, please advise.

Respectfully ubm tted

/

G87L R. P. Mcdonald RPM /BDM:kpc-T.S.7 I I i

Attachments ____

cc: Mr. L. B. Long Mr. L. S. Rubenstein SWORN TO AND SUBSCRIBED BEFORE ME Mr. E. A. Reeves Mr. W. H. Bradford THIS gb. DAY OF J g ,J 1986 Document Control Desk m Washington, DC 20555 [ c fg 8610010422 860918 / /

PDR ADOCK 05000348 My Commission Expires: /n /9, // q G PDR '

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ATTACHMENT 1 Alabama Power Company Response to I. E.Bulletin 85-03 Item (e)

I. HISTORY I. E. Bulletin No. 85-03 (IEB 85-03) requested that all nuclear power reactor facilities develop and implement a program to ensure that switch settings on certain safety-related motor-operated valves (MOVs) are selected, set and maintained correctly. In addition, the NRC requested that a report be submitted to document the results of action item (a) and provide a program and schedule for completion of action items (b) through (d). By letter dated May 14, 1986, Alabama Power Company committed to provide by September 18, 1986 a written report to the NRC addressing this bulletin's action item (a) and the program to accomplish items (b) through (d) including a schedule for completion of these items.

Initially Alabama Power Company worked with its designers (Bechtel and Westinghouse) to evaluate the requirements of IEB 85-03 and participated in the development of a generic program to address action item (a) in conjunction with the Westinghouse Owners Group (WOG). However, the fourth refueling outage for Farley Nuclear Plant Unit 2 minimized staff availability to participate in these efforts. Upon the issuance of the finalized WOG report on April 7,1986, Alabama Power Company continued to work with Bechtel and Westinghouse to develop a specific Farley Nuclear Plant M0V Evaluation Program based on the WOG recommended methodology to the extent practical . This program is described in Section II of this Attachment with a preliminary schedule shown in Attachment 4.

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-i -i Attachment 1-Page 2 II. FARLEY NUCLEAR PLANT MOV EVALUATION PROGRAM The initial phase of the Farley Nuclear Plant MOV Evaluation Program was developed to address the requirements of IEB 85-03 action item (a) to perform an MOV design basis review. The scope of this program for each unit includes fifteen (15) valves in the auxiliary feedwater system and 9 twenty-two (22) valves for the high head injection flow path. All Emergency Response Procedures (ERPs) were reviewed and a listing of ERP steps that require the operation of each identified valve was submitted for designer review. The MOV information and vendor data were obtained for the identified valves presently installed. Bechtel and Westinghouse have completed their design basis review, including the detemination of the maximum differential pressure for valve opening and closing, for each identified valve. The results of this phase of the program are presented in two separate summary reports in Attachments 2 and 3 The second phase of the Farley Nuclear Plant MOV Evaluation Program includes the determination of MOV settings and the development of a comprehensive MOV action plan and a detailed M0V operability test plan.

Determination of MOV switch and thermal overload settings will be based upon the results of the MOV design basis review. Development of a MOV action plan will ensure that other MOV issues are resolved in a cost effective, timely manner with minimum duplication of design and field work activities. This action plan includes the review of other industry-related MOV issues, the MOV maintenance program, and the present M0V settings and the basis for such settings. The development of- an MOV operability test

i a .' Attachment ~1 Page 3 plan will ensure that the integrity of safety systems is not inadvertently challenged. This test plan will include necessary test procedures, alternative test methods and/or justifications for not testing.

Presently, Bechtel is preparing to use and Westinghouse is utilizing the services of the applicable valve vendors and Limitorque Corporation to determine the correct torque switch, torque bypass limit switch, position indication limit switch and thermal overload settings for each valve.

Nominal torque switch settings will be based on the minimum value of operator. thrust required to overcome maximum valve loading conditions (e.g., maximum differential pressure, thermal binding, maximum packing f riction factor). Maximum torque switch sett'ings will be based on the maximum allowed thrust that the valve / operator can withstand without incurring damage. The torque bypass and position indication limit switch setting methodology should be based upon the guidelines provided by the valve vendors / suppliers and/or Limitorque. It is anticipated that the determination of thermal overload settings will be calculated in a similar manner as originally developed.

Alabama Power Company is currently developing a comprehensive MOV action plan to ensure integration of all related M0V issues whenever possible. Related industry MOV issues (e.g., other I.E. Bulletins, I.E.

Information Notices, Significant Event Reports, Significant Operating Experience Reports) and vendor bulletins are being reviewed and evaluated to ensure that all applicable corrective actions have been or will be

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'Page 4 addressed and to verify the methodology and validity of the current Farley Nuclear Plant MOV inspection and adjustment maintenance procedure. In addition to the determination of the present MOV switch and thermal overload settings, Alabama Power Company will also consider the basis for the present settings at Farley Nuclear Plant by reviewing available preoperational'and initial startup test reports, design documents, and equipment maintenance history documents. The calculated and actual MOV setpoint information will_ be compared and any discrepancies in the non-conservative direction will be evaluated and resolved before switch settings are changed. If necessary, a justification for continued plant operation will be developed.

A well-defined MOV operability test plan including necessary contingency plans will be developed. This plan will ensure that the integrity of the Engineered Safety Feature (ESF) systems is not inadvertently challenged, will preclude challenging ESF systems where equipment could potentially be damaged, and will ensure that the conduct of the MOV operability test plan properly interfaces with the adjustment of l

. MOV switcher, and other MOV testing / inspection activities. It is anticipated that the test plan will include detailed test procedures, alternatives to maximum differential pressure testing or adequate i

justifications for not testing. Also included in the test plan will be a verification that the MOV settings have been properly implemented to the i

( extent practical even if testing with differential pressure cannot be i

performed. Contingency plans will provide for responses to situations where a given valve fails its operability test. This test plan will

' . Attachment 1 Page 5 minimize valve testing that requires safety systems to be in potentially detrimental configurations and will ensure that settings are. adequate to 1 support MOV design bases.

t After the development and completion of the MOV action plan and test plan, the next phase of the Farley Nuclear Plant MOV Evaluation Program will I involve the procurement of necessary materials and the scheduling of required activities. All applicable MOV design changes, inspections, switch setting adjustments, and maintenance and test procedures will be reviewed i for planning and scheduling considerations. Material will be procured, detailed work packages compile ~d and work activities scheduled.for each valve

.by integrating these actions into the current Farley Nuclear Plant operating and refueling schedules. The Unit 2 MOV activities are presently planned for the fifth refueling outage, which is currently scheduled for the- fourth quarter of 1987. The Unit 1 M0V activities are scheduled for the eighth refueling outage in the second quarter of 1988.

The final phase of the Farley Nuclear Plant M0V Evaluation Program includes the reissuance of controlled MOV setpoint documents by the designers and the preparation of the final MOV summary report for NRC review. Based on the findings of the Farley Nuclear Plant MOV Evaluation Program, Alabama Power Company will address the necessity of developing a i

new MOV program if the existing Farley Nuclear Plant administrative and I

l design controls are determined to be insufficient to ensure that proper I settings for safety-related MOVs are maintained for the life of the plant.

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' . dttachment1 Page 6 III. SCHEDULING CONSIDERATIONS Alabama Power Company recognizes that the preliminary schedule provided as Attachment 4 for completion of the Farley Nuclear Plant MOV Evaluation Program extends past the IEB 85-03 specified completion date of November 15, 1987. The next Unit 1 refueling outage (seventh) is scheduled to begin in October 1986; however, the prerequisite activities necessary to implement the requirements of IEB 85-03 will not be completed in time to support this outage. As a result, Unit 1 activities will not be completed until the eighth refueling outage, which is scheduled to begin in March 1988. The background for such extension to the NRC specified schedule is described below.

Alabama Power Company's approach'to the resolution of the' issues associated with motor-operated valves within the scope of this bulletin requires the development of a comprehensive MOV action plan to ensure that all applicable MOV issues are integrated into this program and resolved in a timely, cost effective and safe manner. Prior to the issuance of IEB 85-03, Alabama Power Company had already initiated engineering evaluations f

to assess another MOV related issue in response to SOER 84-7 " Pressure Locking and Thermal Binding of Gate Valves". IEB 85-03 prompted additional I

engineering evaluations, and the subsequent issuance of IEN 86-02 " Failure of Valve Operator Motor During Environmental Qualification Testing" and IEN 86-03 " Potential Deficiencies in Environmental Qualification of Limitorque Motor Valve Operator Wiring" required further engineering evaluations. In j an attempt to minimize the duplication of the required work ef forts i

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e . Attachment 1 Page 7 associated with all of these MOV issues, Alabama Power Company requested that Bechtel and Westinghouse integrate their evaluations. Additional considerations for a comprehensive MOV action plan in conjunction with the Farley Nuclear Plant MOV Evaluation Program are IEN 86-29 " Effects of Changing Valve Motor-Operator Switch Settings"; IEN 86-34 " Improper Assembly, Material Selection, and Test of Valves and their Actuators"; IEN 86-71 "Recent . Identified Problems with Limitorque Motor Operators"; and SOER 86-02 " Inaccurate Closed Position Indication on-Motor-0perated i Valves".

Early program schedule delays resulted from the scheduled Unit 2 fourth refueling outage during the second quarter of 1986. This outage minimized Alabama Power Company Staff availability to participate in the efforts associated with the response to IEB 85-03. In addition, the WOG

" Safety-Related M0V Program Final Report", which provided a consistent methodology to WOG utilities for determining maximum differential pressures across the IEB 85-03 identified MOVs, was not issued until April 7,1986 Until this final methodology was received from the WOG, Alabama Power Company was unable to initiate a concentrated ef fort towards the review and documentation of the plant speci#ic design basis for the operation of each MOV.

The determination of new MOV switch settings could not be initiated until the MOV design basis review was completed. To determine the new MOV switch settings, the designers must request that the applicable valve suppliers calculate the required switch settings, since the calculation using a re-established design basis involves equipment design considerations that only the original valve supplier can address. In turn, l

0ttachment1 Page 8 the valve suppliers must request assistance from Limitorque for determination / verification of switch settings. Because all licensees are required to respond to IEB 85-03 and many licensees utilized the same designers, valve suppliers and Limitorque motor operators, there is significant competition for both designer and vendor resources. The designers and valve suppliers must also address the other industry-related l

MOV issues, which places an additional burden on these resources. The competition for these limited resources, in conjunction with the additional burden of the other MOV issues, creates scheduling uncertainties; therefore, Alabama Power Company cannot accurately project when the final MOV switch setting information will be provided. In addition, the determination of MOV thermal overload settings cannot be initiated until the determination of MOV torque switch settings and corresponding thrust values, including locked rotor current, is complete. Alabama Power Company also considers it imprudent to implement MOV switch setting adjustments without a thorough review of the basis for the present M0V torque switch and thermal overload settings at Farley Nuclear Plant. Justification for any necessary changes must be completely understood prior to performance of any adjustments.

Alabama Power Company is concerned about the requirement for MOV operability demonstration testing at~ the maximum differential pressure as specified in part by IEB 85-03 item (c). To subject ESF system equipment to the differential pressure conditions determined by the design basis i review would require placing systems in abnormal operating configurations, operating pumps at shutoff head, and/or raising steam generator pressure to the lowest safety valve setting. While such equipment operability testing l

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e . $t.tachment1 Page 9 may be required initially by the ESF equipment vendors and/or during preoperational testing, this type of testing does not lend itself to an operating facility. To-preclude an unnecessary challenge of ESF equipment and system integrity, all possible testing alternatives must be considered. Until these testing-related concerns are resolved, a detailed operability test plan cannot be developed. Until the MOV operability test plan is developed, including necessary contingency plans, Alabama Power Company is reluctant to implement MOV switch setting adjustments.

In view of the considerations expressed above, Alabama Power Company's preliminary schedule projects that the requirements of IEB 85-03 will not be completed until the Unit 1 eighth refueling outage during the second quarter of 1988. The preliminary -schedule outlined in Attachment 4 is based on certain assumptions that will be clarified as the Farley Nuclear Plant MOV Evaluation Program progresses. The availability of limited

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designer and vendor resources and the resolution of testing concerns are examples of unknowns that might dictate a schedule revision in the future.

Alabama Power Company will inform the.NRC of schedule revisions if the completion of IEB 85-03 is delayed beyond the current projections of the Unit 2 fifth and the Unit 1 eighth refueling outages.

IV. OTHER CONSIDERATIONS 1

Alabama Power Company believes that the comprehensive approach to l

resolution of M0V issues is the most effective means by which the action

! items of IEB 85-03 can be addressed without incurring excessive l expenditures and duplication of work ef fort or unnecessary outages and M0V modi fi cati ons . Furthermore, Alabama Power Company has a high level of l

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?- -. Ittachment 1 Page 10 confidence in the reliability of the safety-related and nonsafety-related motor-operated valves at Farley Nuclear Plant.

The present MOV torque switch and thermal overload settings have been developed through an iterative process. Settings were initially developed by the vendors considering the MOV design basis 'information, which included maximum design differential pressure, provided by the designers. MOV settings were initially established during ' start-up prerequisite testing based on design documents, vendor drawings and instructions. The.

operability of the MOVs was then demonstrated during system preoperational

-testing and/or the initial startup/ power ascension test program. When necessary, the MOV settings were changed within their ' design band with designer concurrence to ensure valve operability. Subsequently, whenever MOV operability problems were. encountered during the first cycle of plant operation, the inplace administrative controls, designer guidelines and the maintenance program were utilized to ensure. that the given MOV was returned I

to an operable status.

A maintenance procedure is currently utilized to set MOV switches and

{ to provide for various motor-operator inspections. This procedure covers l

all valves identified by IEB 86-03. Furthermore, it is scheduled to be performed every sixty (60) months on all MOVs as a .part of the preventive maintenance program. When the MOV maintenance procedure was developed, appropriate vendor instructions and guidelines were considered. The procedure is periodically revised as required to ensure that it meets the l

requirements of Generic Letter 83-28 item 3.2.

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s Attachment 1 Page 11 The inservice test program, periodic surveillance testing, and the preventive maintenance program ensure that the safety-related MOVs are maintained in a high state of operational readiness. In addition, every eighteen months an integrated safeguards test is performed that subjects most of the ECCS motor-operated valves to dynamic test conditions and differential pressures.

Maintenance-personnel are trained in the subjects of motor-operated valve theory of operation, switch adjustment, and preventive and corrective maintenance. Initial MOV maintenance training was conducted by Limitorque personnel prior to Unit 1 commercial operation, and M0V training is still included in the current training program. The Farley Nuclear Plant MOV training program is also periodically upgraded to ensure that maintenance personnel are aware of current MOV maintenance practices and industry issues.

V. CONCLUSION Alabama Power Company has a high level of confidence in the motor-operated valves at Farley Nuclear Plant and believes that the programs and controls associated with the safety-related motor-operated valves within the scope of IEB 85-03 ensure that these valves are maintained in a high state of operational readiness. Alabama Power Company also recognizes the need to address the identified industry-wide MOV issues such that the confidence level of the current Farley Nuclear Plant MOV maintenance and testing programs can be enhanced. However, these MOV issues including IEB 85-03 must be addressed through a comprehensive plan and program.

Therefore, Alabama Power Company will continue to develop and refine the Farley Nuclear Plant MOV Evaluation Program for IEB 85-03 as previously l described and will establish an implementation schedule goal of the Unit 2 i

fifth and the Unit 1 eighth refueling outages.

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ATTACHMENT 2