ML19323C354

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Interim Deficiency Rept Re Steam Generator Pressure Transmitters Not Sufficiently Qualified.Fsar Table Indicates Peak Temp of 296 F;Transmitters Qualified to Only 130 F. Valve Room Instruments Evaluated
ML19323C354
Person / Time
Site: Sequoyah Tennessee Valley Authority icon.png
Issue date: 05/07/1980
From:
TENNESSEE VALLEY AUTHORITY
To:
Shared Package
ML19323C350 List:
References
NCR-SQN-EEB8003, NCR-SQN-EEB8004, NUDOCS 8005150387
Download: ML19323C354 (1)


Text

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' 8005150387 ENCLOSURE SEQUOYAH NUCLEAR PLANT UNIT 2 ENVIRONMENTAL QUALIFICATION OF CLASS IE INSTRUMENTS IN THE VALVE ROOM NCR NO. SQN EEB 8003 AND SCR NO. SQN EEB 8004 10 CFR 50.55(e)

FIRST INTERIM REPORT Description of Deficiency Nonconforming condition SQN EEB 8003 concerns the steam generator pressure transmitters (Foxboro Model E11CM) which are located in the valve rooms at Sequoyah Nuclear Plant. According to the latest revision of the FSAR, the transmitters are not qualified for the worst case environment result-ing from a high energy line break in the valve room. The detrimental environmental aspect is the temperature. FSAR Table 3.11-2 indicates that a peak temperature of 296 F inside the valve room is possible, while the transmitters in question are qualified to only 130 F.

As a result of this condition, all other instrumentation inside the valve rooms has been evaluated. Those instruments that are not qualified which might pose a safety concern are documented in NCR No. SQN EEB 8004.

These are:

1. hin steam pressure transmitters (one per loop)
2. Level solenoid valves which route control air to level control valves which regulate water from the turbine-driven auxiliary feedwater pump to steam generators 1 and 4 (total of two)
3. Steam flow control valve to auxiliary feed pump turbine (total of four) and corresponding handswitches
4. Steam generator main feedwdter isolation valve (total of four) and corresponding handswitches
5. Pressure switches for flow to auxiliary feed pump turbine
6. Pressure switches whica detect an auxiliary feedwater pipe break (total of six)
7. Cable types CPJ, CPJJ, and PJJ used in the valve rooms Corrective Action The steam generator pressure transmitters (total of six) will be replaced with transmitters which have been qualified for operation in the expected environment. All other instruments to which this condition applies are being evaluated and will be dispositioned on a case-by-case basis.

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