ML19308B083
| ML19308B083 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 01/25/1974 |
| From: | DUKE POWER CO. |
| To: | |
| Shared Package | |
| ML19308B080 | List: |
| References | |
| RO-269-73-15, NUDOCS 7912120812 | |
| Download: ML19308B083 (1) | |
Text
.
flegulatory Daccet File W,.a.r-1y 5..cytM yl t:
DUKE POWER COMPANY OCONEE NUCLEAR STATION - UNIT 1 UNUSUAL EVENT REPORT UE-269/73-15 ENGINEERED SAFEGUARDS VALVE HP-20 Description of the Incident on December 27, 1973, Oconee Unit 1 was in the process of being placed in a cold shutdown condition for routine maintenance. The controlling procedure for unit shutdown OP/1/A/1102/10 requires the closure of engineered safe-guards valve HP-20.
The valve was inoperable because the torque limit switch on the electric motor operator was binding, causing the torque switch contacts to open, thus preventing valve closure.
(Reference Oconee FSAR Figure 7-4)
Valve HP-20 is a reactor building isolation valve in the reactor coolant pump seal return header.
The limit switch is on a Limitorque riotor operator, Type SMB-00.
j Regularory Operations, Region II, was notified of the incident on December 27, 1973.
i 2
Corrective Action The torque limit switch was replaced and the valve was tested for proper operability.
The valve was satisfactorily cycled 12 times.
Safety Analysis The unit was shutdown with all reactor coolant pumps secured and in the process of being placed in cold shutdown when the incident occurred. The redundant isolation valve HP-21 was shut thus providing the required isolation.
This incident did not affect the safe operation of the plant or the health and safety of the public.
7912120 [/2
.