Part 21 Report - 1997-430
ACCESSION #: 9706090047
LICENSEE EVENT REPORT (LER)
FACILITY NAME: James A. FitzPatrick Nuclear PAGE: 1 OF 4
Power Plant
DOCKET NUMBER: 05000333
TITLE: Failure of Safety Relief Valve to Open During Set Point
Verification Testing Due to Foreign Material Intrusion
EVENT DATE: 04/28/97 LER #: 97-004-00 REPORT DATE: 05/30/97
OTHER FACILITIES INVOLVED: DOCKET NO: 05000
OPERATING MODE: N POWER LEVEL: 100
THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR
SECTION:
OTHER: 10 CFR 21
LICENSEE CONTACT FOR THIS LER:
NAME: Mr. Gordon J. Brownell, Licensing TELEPHONE: (315) 349-6360
Engineer
COMPONENT FAILURE DESCRIPTION:
CAUSE: E SYSTEM: SB COMPONENT: RV MANUFACTURER: T020
REPORTABLE NPRDS: Y
SUPPLEMENTAL REPORT EXPECTED: NO
ABSTRACT:
During testing of actuating mechanisms (pilot assemblies) for Main Steam
Safety Relief valves (02RV-71A through L) at Wyle Laboratories, valve
02RV-71J (pilot serial number 1217), would not lift at applied test
pressures. The Authority completed an equipment failure evaluation on
the subject pilot assembly to determine the cause of the failure. During
the pilot valve disassembly and inspection, a small screw was found
wedged in the valve operator subassembly, causing the valve not to open
when pressurized.
The source of the loose screw was not established, however, the screw was
identified as material similar to that which is typically removed from
the pilot assembly prior to testing and reattached following completion
of testing.
The laboratory has implemented a test procedure revisions to minimize the
potential for foreign material intrusion into the valve bonnet area
during testing evolutions.
END OF ABSTRACT
TEXT PAGE 2 OF 4
EIIS Codes are in [ ]
EVENT DESCRIPTION
During the plants Fall 1996 Refuel Outage, the actuating mechanisms
(pilot assemblies) for Main Steam [SB] line Safety Relief valves
(02RV-71A through L) were removed and replaced. The subject removed
pilot assemblies were sent to Wyle Laboratories for "as-found" set point
verification testing in accordance with Technical Specifications sections
2.2.1.B and 4.6.E (valve nominal set point 1110 psig). During diagnostic
testing activities, subject pilot for valve 02RV-71J (serial number 1217)
failed to open (lift) at up to a 1250 psig applied test pressure. This
performance characteristic was considered unusual in that: (1) the valve
had been manually opened during a plant shutdown one month prior to
commencing the Refuel Outage; and (2) the valve had a platinum alloy
pilot disc installed to inhibit valve disc to seat oxide bonding.
In an effort to determine the cause of the test failure, the Authority
completed an equipment failure evaluation on the failed pilot assembly.
On April 02, 1997, the pilot was disassembled first by removal of the
stabilizer and related parts in order to permit visual inspection of the
seated pilot disc. No oxide bonding bridge was noted at the interface.
Next, the set point sub-assembly was detached. During its removal, it
was noted that a screw was present and wedged between the lower spring
retainer and the bonnet inside wall. The screw was determined to be
similar to a ball lock pin retaining screw (valve part number 050-0024)
used in the pilot assembly.
CAUSE OF EVENT
Based on the above noted observations and evidence, it was concluded that
the cause for failure of 02RV-71J to lift during "as-found" set point
testing was due to the presence of a ball lock pin retaining screw wedged
between the lower spring retainer and bonnet of the valve pilot assembly.
TEXT PAGE 3 OF 4
CAUSE OF EVENT (cont.)
It was noted that the ball lock pin and retaining screws are typically
removed from the pilot assemblies by Wyle Laboratories prior to valve
testing and reattached upon completion of testing. An examination of the
subject valve upon initial receipt (February 1997) by Wyle Laboratories,
prior to testing, determined that all parts and materials, including its
ball lock pin retaining screws were installed in place. Therefore, the
source of the screw was not established. However, reviews of previous
(set point) test data for valve pilot assembly serial no. 1217 indicate
the last scheduled pressure test was conducted at Wyle Laboratories in
November 1994. Therefore, it was concluded that the most probable cause
for the foreign material intrusion into the valve bonnet area was less
than adequate material controls at Wyle Laboratories during installation
of the ball lock pin lanyards, prior to pilot shipment from Wyle
Laboratories in November/December 1994.
ANALYSIS
This report identifies the potential failure of Wyle Laboratories'
testing facility to maintain material controls which could have resulted
in the failure of a safety function of a Main Steam System Safety Relief
Valve during operating cycle number 12 (November 30, 1994 to October 26,
1996.
The safety relief valves are self-actuated on Main Steam System
overpressurization or pilot assembly actuated by an air operator on
Automatic Depressurization System logic or manual operation. Manual
operation of the 02RV-71J occurred during a September 1996 plant
shutdown. Although the valve functioned as designed, during the pilot
disassembly at Wyle Laboratories on April 02,1997, it was found that the
bearing area between the pilot rod and retainer had indication of
abnormal wear.
Technical Specifications limiting conditions for operation require at
least nine of eleven SRVs be operable and maintain an nominal setting of
1110 psig with an allowable setpoint error of plus or minus three
percent. "As-found" diagnostic test results for setpoint verification
from Wyle Laboratories dated March 06,1997 demonstrated that nine of
eleven SRVs were within Technical Specifications limits.
CORRECTIVE ACTIONS
1. Wyle Laboratories has revised Target Rock 2-Stage SRV Assembly test
procedures to provide instructions for controlling the covering of
the pilot valve vent hole, located in the bonnet valves, to minimize
the potential for foreign material intrusion into the bonnet area.
TEXT PAGE 4 OF 4
CORRECTIVE ACTIONS (CONT.)
2. New York Power Authority's (NYPA) Quality Assurance (QA) Department
now requires notification by Wyle Laboratories prior to conducting
valve testing. This requirement will be maintained until Wyle
Laboratories completes the next scheduled refurbishment and testing
of pilot assemblies at which time QA will conduct a surveillance of
work practice activities.
ADDITIONAL INFORMATION
A. Failed Component
Component Identification - Main Steam System Safety Relief Valve
Pilot
Mark Number - 02RV-71J
Manufacturer - Target Rock Two Stage Safety Relief
Valve
NPRDS Code - T020
Serial Number - 1217
ATTACHMENT TO 9706090047 PAGE 1 OF 1
James A. FitzPatrick
Nuclear Power Plant
P.O. Box 41
Lycoming, New York 13093
315-342-3840
New York Power Michael J. Colomb
Authority Site Executive Officer
May 30, 1997
JAFP-97-0195
United States Nuclear Regulatory Commission
Attn: Document Control Desk
Mail Station P1-137
Washington, D.C. 20555
Subject: Docket No. 50-333
LICENSEE EVENT REPORT: LER-97-004
Failure of Safety Relief Valve to Open During Set Point
Verification Testing Due to Foreign Material Intrusion
Dear Sir:
This report is submitted in accordance with 10 CFR Part 21, "Reporting of
Defects and Noncompliances".
There are no commitments contained in this report.
Questions concerning this report may be addressed to Mr. Gordon J.
Brownell at (31 5) 349-6360.
Very truly yours,
MICHAEL COLOMB
MJC:GJB:las Enclosure
cc: USNRC, Region 1
USNRC Resident Inspector
INPO Records Center
*** END OF DOCUMENT ***
Page Last Reviewed/Updated Wednesday, March 24, 2021