IR 05000341/1987035

Insp Rept 50-341/87-35 on 870818-20.No Violations Noted. Major Areas Inspected:Activities Re IE Bulletin 85-003, Motor-Operated Valve Failures During Plant Transients Due to Switch Settings

ML20235H542
Person / Time
Site:	Fermi
Issue date:	09/23/1987
From:	Eick S, Huber M, Phillips M, Rogers W NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20235H524	List: IR 05000341/1987035 ML20235H523
References
50-341-87-35, IEB-85-003, IEB-85-3, NUDOCS 8710010097
Download: ML20235H542 (4)

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U.S. NUCLEAR REGULATORY COMMISSION'  !

REGION II Report No. 50-341/87035(DRS)

Docket No. 50-34 License No. NPF-33 Licensee: Detroit Edison Company-  !

2000 Second Avenue' )

Detroit, MI 48224 .

' Facility Name: Enrico Fermi Nuclear. Power Plant, Unit 2 j Inspection At: Enrico' Fermi 2 Site, Monroe, Michigan

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Inspection Conducted: August 18-20 l M. P l-( A , 1987 '

J Inspectors: M. P. Huber Y U [t j Date

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S. D 4/U/ 7-Date

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'f W. G. Rogers Z) Q Date-h'fiWY .

Approved By: M. P. Phillips, Chief 9 !2- ' 957 Operational Programs Section

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Inspection Summary )

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Inspection on' August 18-20, 1987 (Report No. 50-341/87035(DRS))'

Areas Inspected: Special safety inspection of the licensee's activities with respect to Inspection and Enforcement Bulletin 85-03 " Motor-Operated

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Valve' Failures During Plant Transients Due to Improper Switch Settings.".

Results: No violations or other items were identifie j B710010097 870924i PDR 0- ADOCK 05000341 PD_R

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DETAILS 1. Persons Contacted

Detroit Edison Company

• F. Agosti, Vice President, Nuclear Operations

• L. Fron, Supervisor, . Nuclear Engineering

• G. Lane, Technician, Mechanical Maintenance

• R. Lenart, Director, Nuclear Engineering

• G. Ohlemacher, Licensing

• J. Rotondo, Supervisor, Maintenance Support

• D. Topel, Quality Assurance  ;

L. Collins, Plant Support Engineer l

• Denotes those who attended the exit meeting on August 20, 1987.

Additional plant technical and administrative personnel were contacted I

by the inspectors during the course of this inspectio . Followup on Previously Identified Items

{0 pen) Unresolved Item (341/87022-02(DRS)): Backseating of valves using the Limitorque motor-operator torque switc It has been the practice of Fermi 2 to backseat valves, halting motion of the valve using the torque switch motor cutoff. This was pointed out as highly undesirable in the bulleti DECO has reviewed the acceptability of backseating globe and I gate valves with the valve manufacturers, the William Powell' Company and Anchor / Darling Valve Compan In correspondence between the licensee '

and the valve manufacturers, it was stated that based on an analysis which included torque switch setting versus operator output information from Limitorque and the effects of impact loading (strain hardening of i

valve components) and inertia loading, the valve assembly will withstand torque switch backseating to a limited exten Since this issue has been raised, DECO has adopted the philosophy not to backseat any valve DECO was in the process of changing the wiring for these valves so that the opening travel would be stopped with the limit switch instead of the torque switc Engineering Design Packages (EDP)

L were generated and used to address the problem.

l Inspector observations during-testing, noted that although these wiring changes had been implemented and the limit switches set according to the EDPs for valve E41-50-F011 it was evident that the valve continued to backseat during testing. Additional switch adjustments were then made and the valve travel was halted prior to the backseat using the limit switc The EDPs were written to turn off the motor at one-half turn of the valve stem away from the backsea As was the case with the above valve, the one-half turn of the valve stem away from the backseat did not appear to be fully adequate in assuring no backseating of valves occurre The

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licensee agreed with the inspectors that this issue and more conservative limit switch settings.need continued evaluatio Resolution of this item remains open, pending further' inspectio . IE Bulletin Followup (0 pen) ICB 85-03: Motor-0perated Valve (MOV) Common Mode Failure During Plant Transients Due to Improper Switch Setting The inspectors observed the licensee's performance of diagnostic testing of Motor-Operated Valves (MOV) addressed in the IE Bulletin 85-03 l

" Motor-0perated Valve Common Made Failures During Plant Transients Due !

to Improper Switch Settings." The purpose of the bulletin was to request licensees to develop and implement a program to ensure that switch settings on certain safety-related motor-operated valves are selected, set and maintained correctly to accommodate the maximum differential pressures l i

expected on these valves during both normal and abnormal events within the design. basis. The licensee used the. Motor-0perated Valve Analysis and Test System (M0 VATS) to detect degradation, incorrect adjustments, and other abnormalities that might-exist in the motor operators and valve The valve testing was being done'in accordance with maintenance work requests and was being used solely as a maintenance tool to adjust the switch settings of the MOVs. The licensee had not yet established a program to address testing or long-term operability of the 85-03 bulletin j valves, or for implementing the bulletin requirements, but indicated that

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they would develop a program to accomplish this. To date, the licensee's i

response to the bulletin has been focused on valve design requirements rather than defining a program to ensure valve operabilit During this initial inspection, in addition to observing the licensee's 1 MOV testing, the inspectors reviewed drawings, procedures and engineering records, discussed the valve test program being considered for implementation and reviewed test data, and received additional documents for further review and discussion. The detailed inspection findings are addressed belo I Test Observation The licensee had scheduled nine MOVs to be tested using the MOVATS i

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equipment during this maintenance activity. Due to maintenance and inspection scheduling, only two valves were selected for inspection as representative examples: High Pressure Coolant Injection (HPCI)

pump test return to the Condensate Storage Tank (CST) downstream isolation valve E41-50-F011, using a Limitorque SMB-0 operator; and the HPCI exhaust line vacuum breaker outboard isolation valve E41-50-F079, using a Limitorque SMB-000 operator. Both valves appeared to be in good physical condition and in working order; however, during the testing of-the E41-50-F011-valve, it was learned that the "as-found" open thrust (14740 lbs) did not meet the target thrust in the static condition (25593 lbs). In order to meet the target thrust, the "as-left" open torque switch setting was raise Also, the open target thrust desired on this valve slightly exceeds the rating of the motor operato The acceptability of this condition is being evaluated by Deco engineering and Limitorqu :l

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' ' Currently, DECO.has no-ability to determine.th'e' target thrusts-or the criteria' for 'any' torque switch occlimit : switch settings -

on MOVs. The licensee: stated thatLit was their intent to' develop specific setting criteria from'the' data base being'provided from the initial.MOVATS valve testin Until'then, MOVATS will. provide-

' DECO'with preliminary calculations"or targeted torque switch and limit switch setting Valve Testing Under Differential-Pressure (dP) Conditions The licensee' indicated that no plans existed:to test the bulletin valves; under dP conditions that might exist in a system when th valve was required to operat The inspectors. indicated that the licensee shouldLiaclude dP. testing c

of. valves in their program, when it.is developed. However, if dP testing was not possible,'. adequate justification would be required to support this, Additional Considerations Most of.the valve testing and data analysis at Fermi.2 remained.to ';

be completed, as-well as the development of a program.to address th bulleti A comprehensive program will enable the licensee to 1- obtain meaningful data and provide the ability to achieve conclusive 'l

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l result The diagnostic testing of MOVs can be a useful tool in the. analysis of valve characteristic As was the case in the valve' tested, the testing provided some insight as to the current conditions'of valve -

switch settings and proved instrumental in ensuring that switch

settings were selected and set correctly in accordance with the valve design requirement .

Additional inspection and evaluation of test results will be necessary in the future, once the licensee completes the response l to IE Bulletin 85-03, to insure the objectives of 85-03 are me t 4. Exit Interview The inspectors met with.the licensee representatives'(denoted in-Paragraph 1) on August 20, 1987, to discuss the. scope and findings of the inspectio The. licensee acknowledged the statements made by the-

inspectors with respect'to_ items discussed in the report. .The. licensee l- also. indicated that no proprietary information had been reviewed by the_

i nspectors.'

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