ML19261B645
| ML19261B645 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 02/16/1979 |
| From: | TENNESSEE VALLEY AUTHORITY |
| To: | |
| Shared Package | |
| ML19261B644 | List: |
| References | |
| NCR-SQN-002, NCR-SQN-2, NUDOCS 7902280321 | |
| Download: ML19261B645 (1) | |
Text
e ENCLOSURE SEQUOYAll NUCLEAR PLANT UNITS 1 AND 2 RL\\CTOR COOLANT PUMP TIE ROD EMBEDMENTS NCR SQN-002 FINAL REPORT Description of Condition Subsequent to completion of construction of reactor coolant punp (RCP) tie rod embedments, Westinghouse performed a new LOCA analysis.
TVA's review of this analysis revealed an incompatibility between calculated loads and support design loads which indicates that the concrete shear capacity might be exceeded in three of these embedments in each unit.
Safety Implications If the condition had not been discovered and corrected, failure of the embedments during a design basis LOCA could have resulted in multiple RCS pipe breaks, and LOCA effects in excess of the design basis may have resulted.
Corrective Action The embedments were analyzed for the increased loads, and it was con-firmed that a modification would be required.
Consequently, two addi-tional anchor bolts were added to each of the three embedments per unit, and stiffener plates were added to one of these embedments per unit.
Means to Prevent Recurrence TVA will take into consideration the possibility of a load increase in future NSSS supports. There are no generic implications to Watts Bar or any other TVA plant.
790228032(
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