05000335/LER-1980-025-01, /01T-0:on 800512,during Planned Secondary Shutdown for Turbine Maint,Steam Header Would Not Depressurize Following Steam Stop Closure Due to Sheared Bypass Valve Stems.Cause Undetermined.Valve Stems Replaced

/01T-0:on 800512,during Planned Secondary Shutdown for Turbine Maint,Steam Header Would Not Depressurize Following Steam Stop Closure Due to Sheared Bypass Valve Stems.Cause Undetermined.Valve Stems Replaced

ML17266A212
Person / Time
Site:	Saint Lucie
Issue date:	05/26/1980
From:	Schoppman M FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML17208A689	List: 05000335/LER-1980-025-01, /01T-0:on 800512,during Planned Secondary Shutdown for Turbine Maint,Steam Header Would Not Depressurize Following Steam Stop Closure Due to Sheared Bypass Valve Stems.Cause Undetermined.Valve Stems Replaced
References
LER-80-025-01T, LER-80-25-1T, NUDOCS 8006110042
Download: ML17266A212 (3)

LER-1980-025, /01T-0:on 800512,during Planned Secondary Shutdown for Turbine Maint,Steam Header Would Not Depressurize Following Steam Stop Closure Due to Sheared Bypass Valve Stems.Cause Undetermined.Valve Stems Replaced

Event date:
Report date:
3351980025R01 - NRC Website

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Durin

'a lanned secondar lant shutdown for turbine maintenance

. it was noted that the main steam header would not de ressurize followin steam

~05 stems were sheared with the valves stuck in the "o enN position. 'Althou h'QS onl three inch warm-u lines were involved the lant did not meet'he

~03 intent of T.S. 3.7.1.5 and the FSAR anal sis.

Hh n 81'cooled the valves were repai.red.

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A follow-up reoort will be.issued.

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Event Descri tion and Probable Conse uences I

The NSIV bypass valves are not specifically mentioned in the Technical Spec-

,ifications or FSAR analysis.

However, their failure in the open position provides a path for continued blowdown of the steam generators on main steam rupture downstream of the HSIV.

Rupture upstream of a t1SIV would not

'e affected because of a check valve jn series with the bypass valve.