ML20236L926
| ML20236L926 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun  |
| Issue date: | 07/31/1987 |
| From: | Andrews R OMAHA PUBLIC POWER DISTRICT |
| To: | Gagliardo J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| IEB-85-003, IEB-85-3, LIC-87-552, NUDOCS 8708100409 | |
| Download: ML20236L926 (3) | |
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Omaha Public Power District 1623 Harnetj Omaha, Nebraska 68102 402/536-4000 July 31, 1987
@b0N LIC-87-552 Al)G 3 W Mr. J. E. Gagliardo, Chief Reactor Projects Branch U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 1000 Arlington, Texas 76011
References:
1.
Docket No. 50-285 2.
Letter NRC (J. E. Gagliardo) to OPPD (R. L. Andrews) dated July 1, 1987
Dear Mr. Gagliardo:
SUBJECT:
Inspection Report 50-285/87-17 The subject inspection report identified one violation.
The violation involved failure to identify and evaluate an as-found over-thrust condition in Limitorque valve operators.
Pursuant to the provisions of 10 CFR Part 2.201, please find attached the Omaha Public Power District's response to this violation.
Sincerely, R. L. Andrews Division Manager Nuclear Production RLA:rge Attachment c:
LeBoeuf, Lamb, Leiby & MacRae 1333 New Hampshire Ave., N.W.
Washington, DC 20036 Mr. R. D. Martin, NRC Regional Administrator Mr. A. Bournia, NRC Project Manager Mr. P. H. Harrell, NRC Senior Resident Inspector j
8708100409 e70731 l
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Attachment t
During an NRC inspection conducted on June 8-12, 1987, a violation of NRC i
requirements was identified.
The violation involved a failure to identify and evaluate an as-found over-thrust condition in Limitorque valve operators.
In accordance with the " General Statement of Policy and Procedure for NRC Enforcement Actions," 10 CFR Part 2, Appendix C (1987), the violation is listed I
below:
10 CFR 50, Appendix B, Criterion XV and XVI as implemented by the OPPD Quality Assurance Manual QADP-17 states, in part, " Measures shall be established to control materials, parts, or components which do not conform to requirements in order to prevent their inadvertent use...
Measures shall be established to assure that conditions adverse to quality, such as failures, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly
)
identified and corrected...".
Contrary to the above, measures were not established to identify and control the use of Limitorque valve operators which were found to have thrust switches set so that thrust limits of the operators had been exceeded.
This is a Severity Level IV violation.
(Supplement I) (285/8717-02)
OPPD's Resoonse The Reason for the Violation if Admitted During the 1985 refueling outage, M0 VATS, a new testing technology, was introduced at the Fort Calhoun Station.
With the use of this new test procedure, Limitorque operators could be tested for the first time to perform in situ measurement of the conditions of a valve.
In an effort to respond to IE Bulletin (IEB) 85-03, the HPSI valves were tested.
An outcome of this test was a finding that several operators were found with thrust settings above the range recommended by the manufacturer's specifications.
At the time of the occurrence, OPPD personnel held several discussions evaluating the impact and the problems associated with the as-found over-thrust condition.
Investigation of past operating history of the Limitorque operators j
tested had not produced any records of operator failure. After visual inspection and M0 VATS testing using the appropriate torque switch settings, the valves exhibited normal test results with no evidence of operator performance degradation. M0 VATS analysis reports confirmed field observations.
With this background, it was felt that the valves could be considered operational.
With the valves testing normally, it was thought appropriate at the time that further review or other documentation was not needed.
s
.r Attachment (continued) l The Corrective Steps Which Have Been Taken and the Results Achieved Prior to inspection 87-17, the M0 VATS testing procedure had been rewritten and j
implemented.
The revised procedure established criteria to help eliminate the possibility of drastic over-thrusting of a Limitorque valve operator.
- Also, i
the procedure further defined valve operator capacity more clearly; again, with I
the goal of eliminating thrust setting errors.
These actions eliminated most J
of the procedural problems.
During the subject inspection, an engineering firm was contacted for a preliminary stress analysis, based on fatigue testing of the worst case loading conditions. The valve operators were viewed as being acceptable from a j
structural and operability standpoint.
Preliminary limits are for 240 to 250 j
cycles of operation with the overstress condition that existed prior to the 1985 refueling outage.
To date, the valves are estimated to have undergone 200 cycles.
Further analysis is ongoing to evaluate the impact on the expected life of the over-thrusted valves.
The Corrective Steps Which Will be Taken to Avoid Further Violations Before the 1988 refueling outage, the following actions will be completed.
j Additional review and revision, as required, of the M0 VATS testing a.
procedures will be performed to clearly define and establish methods to set valve thrusts and to ensure that the capacity of the operator or valve will not be exceeded.
b.
A review of the processes of reporting and evaluating test results will be performed. Appropriate actions will be taken to ensure procedures and personnel correctly and effectively respond to adverse findings.
Further evaluations will be made on over-thrusted valves to determine the c.
possible damage and life cycle effects on the valve operators. The engineering analysis of those valves that exceeded thrust criteria will ensure sufficient design margin for continued operability and will provide a conservative schedule for component replacement if required.
The Date When Full Compliance Will be Achieved OPPD is presently in full compliance.
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