ML19337A250
| ML19337A250 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/04/1980 |
| From: | Cross J TENNESSEE VALLEY AUTHORITY |
| To: | Schwencer A Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8009090370 | |
| Download: ML19337A250 (2) | |
Text
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- ,TENN_ESSEE VALLEY LAUTHORITY
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criATTANOOGA. TENNESSEE 37401~
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500A Chestnut' Street Tower-II'
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- September 4, 1980-.
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-Director of Nuclear. Reactor. 'Regu1'ation 1 Attention:'-Mr.;A. Schwencer,-Chieff Licer.aing Branch No. 2
. Division of Licensing, tU.S.1Nuolear Regulatory Commission-
' Washington, DC-20555
Dear-Mr.jSchwencer:
'In-theIMatter of the Applicat' ion or'
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Docket Nos. 50-327 Tennessee Valley' Authority'
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50-328
~ Enclosed is additional'information $equested by O. Parr, Auxiliary Systems
- Branch Chief,l on temperature control? ibr the main steam valve rooms at.
Sequoyah Nuclear Plant. This enclosed information revises L. H. Hills' letter to you dated Julp'29,-1980.
Very.truly yours,.
TENNESSEE VALLEY AUTHORITY J. L. Crosa:
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Executivo assis3 ant to the
- Manager of Poster
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'N6tary[ublio 6:
7 My Congiss*1. Expli.
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2-Enclosure-7 s
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An Equal Opportunity Employer
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1 4 ENCLOSURE
-SEQUOYAH NUCLEAR PLANT Temperature C,ontrol System for the' Main Steam Valve Rooms The main steam safety valves are set such that'they will operate (open) at their technical specification set pressure in an ambient environment of 80 degrees Fahrenheit and 120 degrees Fahrenheit. The 120 degrees Fahrenheit limit is chosen in order to maintain margin between the set pressure (which decreases with increasing room temperature) and the steam
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-line operating pressure. This reduces unnecessary actuations and-potential economic penalties.
If the control system should fail,-the temperature in the main steam valve room will remain.above 80 degrees Fahrenheit when i.
the primary system is above 350 degrees Fahrenheit. Thus, with the temperature control system operable or inoperable, the main steam safety valves will.open at or below their technical specification set pressure.
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