ML20002A385
| ML20002A385 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 07/24/1964 |
| From: | Boyd R US ATOMIC ENERGY COMMISSION (AEC) |
| To: | |
| Shared Package | |
| ML20002A384 | List: |
| References | |
| NUDOCS 8011170030 | |
| Download: ML20002A385 (2) | |
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i UNITED STATES ATOMIC ENERGY C0hNISSION
}lgRDS ANAIXSIS BY_ TIIE RESEAR01 AND POWER REACTOR SAFETY BDANOl DIVISION OF REACTOR LICENSING H
IN Tile MATTEP OF YANKEE ATOMIC ELECTRIC COMPANY PROPOSED OIANCE NO. 53 DOCKET NO. 50-29 Introduction Pursuant to the provisions of Section 50.59 of the Commission's regulations, Yankee Atomic Electric Company in Proposed Change No.
53, dated April 24, 1964, requested authorization of a change in the Technical Specifications attached as Appendix A to License No. DPR-3.
=P This Proposed Change would pemit operation of the primary system pressuri:er with the solenoid relief valve line scaled off.
Operation 6
m would be permitted in this manner if the solenoid relief valve cannot be repaired during the outage for installation of Core IV.
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Di scusion j
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Over-pressure prctection for the primary system pressuri:er is provided 1
by a spray cooler, a solenoid relief valve, and two safety valves, which are set to operate at 2250, 2350, 2485, and 2560 psig, respe:-
tively. The normal prinary system pressure is approxirately 2000 psig.
The spray cooler is designed to linit the routine small pressure vari-1 atic.is, and the relief and safety valves are designed to relieve large l
pressure surges.
Gross overpressurization could result in the unlikely event that the reactor continued to operate following loss of system Icad; however, the turbine tripout scrams the reactor to prevent this cendition from occurring.
p The solenoid relief valve was provided in the original design to
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reduce wear of the safety valves and thereby reduce safety valve main-tenance. The solenoid relief valve line contains a motor operated isolation valve to close the line should the solenoid valve fail to seat properly. Yankee has reported that control of the primary system pressure can be maintained to close limits and that action of the solenoid relief valve and safety valves has not been required, llowever, the solenoid relief valve has failed to seat following manual testing,
.l and closure of the isolation valve for extended periods has been required.
So.mc cperat icnal advantages can be gained by use of the solenoid relief v ilve, if it can be made to function properly.
Yankee has PG029gSMAl..*
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2-stated that the valve will be returned to the vendor for repair during the Core IV outage, but has requested permission to operate without the valve if repa.r is not possible.
Since operating experience to date indicates that the valve is not necessary and satisfactory pressure relief is still provided by the spray cooler and two existing safety valves, it is our opinion that the Proposed Change would not result in a significant change in the safety of operation.
Conclusion I
h'e have concluded that the Proposed Change does not present significant hazards considerations not described or implicit in the hazards summary report, and that there is reasonable assurance that the hecith and safety of the public will not be endangered.
Origir.al sigt.ed by.
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Rc;tr S. End Roger S. Boyd, Chief Research 6 Power Reactor Safety Branch Division of Reactor Licensing Date:
JJL 2 41954