ML18024A678

From kanterella
Jump to navigation Jump to search
LER 79-001/03L-0 on 790113:during Test of high-pressure Injection Coolant Sys,Steam Supply Valve FCV-73-16 Failed to Open,Rendering Sys Inoperative.Caused by Failure of Limitorque Valve Operator Limit Switch
ML18024A678
Person / Time
Site: Browns Ferry Tennessee Valley Authority icon.png
Issue date: 02/08/1979
From:
TENNESSEE VALLEY AUTHORITY
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML18024A677 List:
References
LER-79-001-03L, LER-79-1-3L, NUDOCS 7902130193
Download: ML18024A678 (4)


Text

e Form BF-17 BF 15.2 6/09/78 LER SUPPLEi>IENTAL INFORMATION BFRO 260/ 791'echnical Specification Involved 3. 5. E Reported Under Technical Specification . 6.7.2.b 2 Date of Occurrence 1/13179 Time of Occurrence 2215 Unit Identification and Descri tion of Occurrence:

During normal power operation, while testing 'the HPCX auxiliary oil pump, steam supply valve FCV-73-16 failed to open, rendering the HPCX system inoperable.

Conditions Prior to Occurrence:

Unit operating at 57 percent powei.

Action specified in the Technical Specification Surveillance Requirements met-due to ino erable e ui ment. Describe.

ADS, CSS, RHR (LPCX), and RCXC vore satisfactorily gested in accordance with T. S. 4. 5. E. 2.

A arent Cause of Occurrence: '

Mechanical failure of the geared limit switch finger bases and rotors at the.

. mounting to the limit switch gear box for the limitorque .(SMB-2) valve operator associated with the valve had caused it to be inoperable.

Anal sis of Occurrence:

Redundant systems were available. No hazard to the~public health and safety.

Corrective Action:

The broken limit switch parts were replaced; maintenance was conducted on the HPCX auxiliary oil pump; and the system was satisfactorily tested and returned to operation after replacing the HPCX rupture disc (which had been noted to be leaking) with an improved disc with vacuum support. FCV 73-16 was'nspected on units 1 and 3 and found to .be undamaged.

Failure Data:

None previous.

Tennessee Valley Authority - Browne Ferry Nuclear Plant

0