W3P85-1188, Forwards Justification for Continued Operation of Borg- Warner pneumatic-hydraulic Actuator Model Pn 39400 for Valves ISI-V1501B & ISI-V1503A.Qualification Expected to Be Complete by Nov 1985

Forwards Justification for Continued Operation of Borg- Warner pneumatic-hydraulic Actuator Model Pn 39400 for Valves ISI-V1501B & ISI-V1503A.Qualification Expected to Be Complete by Nov 1985

ML20127J453
Person / Time
Site:	Waterford
Issue date:	05/16/1985
From:	Cook K LOUISIANA POWER & LIGHT CO.
To:	Knighton G Office of Nuclear Reactor Regulation
References
W3P85-1188, NUDOCS 8505210472
Download: ML20127J453 (4)

Text

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POWER & LIGHT NEW ORLEANS LoWISIAr% 70174-8000 . (504]388-2345 U$Ol$SYS M May 16, 1985 W3P85-1188 A4.05 Director of Nuclear Reactor Regulation Attention: Mr. G. W. Knighton, Chief Licensing Branch No. 3 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

Waterford 3 SES Docket No. 50-382 Environmental Qualification-Borg Warner Actuators

Dear Sir:

Please find attached a Justification for Continued Operation for the Borg-Warner actuators for valves ISI-V 1501B and ISI-V1503A. As discussed in the attached, we expect qualification to be complete by November 1985.

Please feel free to contact me or Robert J. Murillo, Safety and Environ-mental Licensing Coordinator, should you have any questions.

Very truly yours, K. W. Cook Nuclear Support & Licensing Manager KWC/RJM/azs cc: E. L. Blake, W. M. Stevenson, R. D. Martin, D. M. Crutchfield, H. Garg, J. Wilson, G. L. Constable y2am m%2 P

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x JJUSTIFICATION FOR CONTINUED OPERATION BORG-WARNER PNEUMATIC-HYDRAULIC ACTUATOR

..MODEL-PN 39400 FOR VALVES ISI-V1501B and ISI-V1503A

. I.- ' SAFETY FUNCTION.

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The pneumatic-hydraulic actuators serve containment isolation' valves ISI-V1501B and ISI-V1503A in'the Shutdown Cooling Line.

The isolation valves are normally closed and will be opened in the Shutdown Cooling Mode, and Long Term Recirculation Mode following a

.'Small'Line Break. In the Long Term Recirculation Mode the valves

l. must open 16-24 hours after a Small Line Break and remain open.

II. BACKGROUND

.LP&L~ submitted a JIO to the'NRC, reference one (1), stating.thatithe

.,. ' environmental qualification of the Borg-Warner actuators should be complete byJcommercial operation. The JIO also'_ explicitly stated that the NRC would be notified if the testing schedule should slip beyond~ commercial operation. Recently, the. environmental qualifica-tion test program for these actuators was halted.by LP&L due_to

'various equipment. anomalies that were observed during the testing.

' phase of ' th'e program. LP&L has-evaluated these anomalies and imple -

mented corrective measures. The' environmental' qualification of these-

. . actuators is now expected to be complete in~ August 1985. This

, ' Justification for Continued Operation (JCO),therefore supplements (the original JIO, reference one (1), . and includes an evaluation 'of.

.the anomalies and the identification of'LP&L corrective. measures. .

• , III. EVALUATION-4- '

The, equipment anomalies that resulted during the'. test' program were

. determined to be' uniquely attributable to the inherent elements'of the; test program. LP&L has conducted a safety evaluation and; deter-

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mined that the' test' program anomalies does not have applicability to.

.or'have any adverse. safety impact on the installed equipment at Waterford--3. The following: anomalies were. observed during the test program.

1. Motor / Pump Mechanical' Coupling Separated nomaly - Seismic,' Day 1 a

The_ pump and motor shafts are connected by a rotating mechanical i ?: . coupling. The coupling is keyed to the m(tor. shaft and laterally

by a set. screw. During the test, the set screw was-found to have backed off the. motor. shaft. The anomaly Aas. attributed to not

using,an, adhesive agent on.the set screw. The set screw anomaly

- , .has not~ occurred for the entire envelope of the Borg-Warner qualification. program, and therefore, the failure was evaluated

to be-a random failure.

! 2. Motor / Electrical Connector Anomaly - LOCA/MSLB, Day 1

• ' . An anomaly' occurred which was due to the improper connection of the

, motor. The . motor was connected as a single phase motor by the F }t

< . testing laboratory. The resulting current caused the operator s.

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. to fail. An additional motor which was included in previous-radiation and aging test program and was properly electrically-connected did not experience this failure mode.

Proper wiring of the installed equipment at Waterford 3 has been_ verified through the testing program.

~ 3' . Solenoid Valve Anomaly - LOCA/MSLB, Day 14

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' The' solenoid valve failed ~ due to chemical attack on the connec-tion at.the solenoid coil. This anomaly is attributed to the fact that the conduit which was removed from the electrical controls when the motor connector failed was not replaced.

The actuators installed at Waterford 3 each.have 4 solenoid 1

. valves which have.the proper conduit and environmental protec-

' tion.

.4. . Motor / Pump Mechanical-Coupling and Hydraulic Filters - LOCA/MSLB As a result of the multiple test runs, excessive contamination of the hydraulic fluid occurred. The hydraulic fluid contamination clogged the small filter in the solenoid actuated Pilot valve which caused-an inordinate excessive pressure on the pilot valve.

and thus.resulted in the seizure of the pump and the decoupling of the motor shaft and pump due to the extreme torque. The de-

. coupling of'the motor shaft resulted in metal residue in the fluid and clogging of the filter. The actuator 1 was in fact

, subjected to six actuations at peak adverse environmental con-ditions. Each additional cycle caused added. chemical spray ingress. :The testing conditions were thus excessive, beyond the l' requirement-of conservative qualification.

5. ' Pilot Piston - LOCA/MSLB, Day 1 During manufacture and' assembly the wrong size shim was used on the Pilot Piston / cylinder configuration. As a consequence of the improper tolerance,1the actuator failed immediately when operated at the test peak temperature.- The installed equipment'at Water-ford 3 is.similar to the test specimen except that the installed equipment does not have the pilot piston on the nitrogen side of the actuator. The installed equipment has redundant solenoids; the test specimen has only.one solenoid. The anomaly is there-fore not applicable to the equipment installed at Waterford 3.

" IV. CORRECTIVE MEASURES LP&L has recommended design changes which will further enhance-the environmental survivability of'the test specimen and also preclude test. specimen' anomalies. These design changer have been evaluated

'with'and: approved by Borg-Warner, and the changes will be implemented on the test specimen immediately. The desi F a changes will entail the following:

1. A check valve vill be added to the hydraulic reservoir. to limit.

ingress of chemical spray and other contaminants into the hydraulic

• . fluids.

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2. The motor / pump coupling will be secured by indenting the motor shaft and adding one (1) additional set screw.

3. ' The solenoid valve electrical conduit pathway will be sealed.

4. The hydraulic filter size will be increased to reduce the

' potential.for clogging.

, 5. All terminal blocks will be removed and replaced with quali-fied splice materials.

~6. Quality Control during equipment manufacturing will be increased to. ensure the proper shims are used.

- 7. Sealed. conduits will be used to provide increased protection to electrical circuits.

V. SCHEDULE The qualification test. program will be completely re-run starting mid

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May 1985. LP&L will supervise and witness all facets of' the test pro .

~ gram, providing onsite trouble shooting, anomaly resolution, and expediting in'accordance with detailed test procedures. .The qualifi-

. cation of the test specimen is expected to be complete by August-1985.

A letter notifying the NRC of the successful completion of the quali-J fication of the Borg-Warner actuators would be submitted to the NRC by, November :1, 1985.

Borg-Warner will provide LP&L replacement components identical to the test specimen, and the replacement components will be installed subject to qualification .in the Fall. of 1985 not later than November 30.

l VI. REFERENCE

1. :LP&L Justification'for Interim Operation, W3P84-0416, dated 4/9/84.

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