United States Nuclear Regulatory Commission - Protecting People and the Environment

Amer Gen
A PECO Energy/British Energy Company

Michael T Coyle
Vice President

Clinton Power Station
PO. Box 678
Clinton, IL 61727
Phone. 217 935-8881 Ext. 4161

U-603314

4F.140

January 14, 2000

Docket No.50-461 10CFR21.21

Document Control Desk
Nuclear Regulatory Commission
Washington, D.C. 20555

Subject: 10CFR21 Interim Report 21-99-027/028: Hydramotors Fail to Meet Fail Safe Return Time Test Acceptance Criteria and Recycle Criteria Due to Possible Malfunction of ASCO Hydramotor Pump Assemblies

Dear Madam or Sir:

This letter is notification that evaluations of two potential deviations under the provisions of 10CFR, Part 21, will not be completed within the 60-day evaluation requirement of the rule. The affected parts have been returned to the supplier for failure analysis to be performed by the current manufacturer. Completion of the failure analysis will not support the 60-day evaluation requirement. Clinton Power Station (CPS) expects to complete the evaluation of this issue, including the failure analysis, by March 10, 2000. Please note that the deficiencies in these parts were identified during pre-installation testing so the affected components were not installed at CPS.

On November 19, 1999, during refurbishment, CPS Electrical Maintenance personnel installed a new pump assembly from stores into a hydramotor (electro-hydraulic push-type linear actuator) for the B Train Control Room Supply Air Damper. During bench testing of the hydramotor, the redundant relief valve did not meet the fail safe spring return time test acceptance criteria provided in the hydramotor actuator maintenance procedure. The new pump is a possible cause of the test failure. The old pump assembly was reinstalled in the hydramotor and the unit was tested with satisfactory results. The new pump assembly has been returned to the supplier for failure analysis to determine the cause for the test failure.

The failure of the new pump assembly to meet the test acceptance criteria has been determined to be potentially reportable under the provisions of 10CFR, Part 21.

The hydramotor is model number NH91G2073L33, manufactured by ITT Barton. The new pump assembly is part number NS109761AQ, manufactured by ITT Barton. ITT Barton has been sold to Automatic Switch Company (ASCO) and ASCO now has responsibility under 10CFR21 for this ITT Barton material. CPS has issued Condition Report 1-99-11-134 to track the investigation and resolution of this issue.

On December 1, 1999, during a separate hydramotor refurbishment activity, CPSElectrical Maintenance personnel installed a new pump assembly from stores into a hydramotor for the B Train Standby Gas Treatment System Fuel Building Isolation Damper. During in-shop functional testing of the hydramotor, the hydramotor recycle rate was not consistent with the criteria provided in the hydramotor actuator maintenance procedure. Recycle occurs when sufficient hydraulic fluid is internally bypassed in the hydramotor for the shaft to move 0.10 inch off the fully stroked position. At that point, the hydramotor restarts to drive the shaft back to the full stroke position. The new pump is a possible cause of the functional test failure. The old pump assembly was reinstalled in the hydramotor and the recycle times were satisfactory. The new pump assembly has been returned to the supplier for failure analysis to determine the cause for the test failure. The failure of the new pump assembly to meet the test criteria has been determined to be potentially reportable under the provisions of 10CFR, Part 21.

The hydramotor is model number NH95G4673P203, manufactured by ITT Barton.

The new pump assembly is part number N5109761EQX07, manufactured by ITT Barton. As stated above, ASCO has responsibility under 10CFR21 for this ITT Barton material. CPS has issued Condition Report 1-99-12-004 to track the investigation and resolution of this issue.

Additional information about this issue may be obtained by contacting J. W. Blount, Nuclear Station Engineering, at (217) 935-8881, extension 3638.

Sincerely yours,

Michael T. Coyle
Vice President

RSF/krk

cc: NRC Clinton Licensing Project Manager
NRC Resident Office, V-690
Regional Administrator, Region III, USNRC
Illinois Department of Nuclear Safety
INPO Records Center
ASCO

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