ML19290A290

Explains That 4,000 F Temp Reading at Core Thermocouple Was Erroneous.Temps Above 2,700 F Physically Impossible to Measure

ML19290A290
Person / Time
Site:	Crane
Issue date:	10/19/1979
From:	Jay Collins NRC - TMI-2 OPERATIONS/SUPPORT TASK FORCE
To:	Vollmer R NRC - TMI-2 OPERATIONS/SUPPORT TASK FORCE
References
NUDOCS 7911060085
Download: ML19290A290 (1)

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JTCollins N MEMORANDUM FOR:

nichard H. Vollmer, Director TMI Support 3.

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-,._.,,J.. L. Uohn T. dollins Deputy Director, IMI Support

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x N 'TMI ACCIDENT - HIGH TEMPERATURE READINGS FROM CORE t

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THERMOCOUPLES

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t Referencet Memo from Bernid Snyder, OPE, to Commiasioner Cilinsky, September 27, 1979 i

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p-i I have reviewed the above mentioned memo from Bernie Snyder regarding temperature i

readings from TMI-2 core thermocouples. It is understood that some readings were reported to be as high as 4000 F during the time the core was assumed to be 0

uncovered. From the information obtained from the National Bureau ~of Standards

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end from R. Shepherd, Program Manager I&C Division, true temperature indications I

.. above about 27000F are physically impossible for Cr-Al thermocouples (th'a type employed at TMI). The real limitation being that this type of thermocouple has a melting point slightly above 2700 F.

A number of possibilities were presented for the high readings, all of which would falsely indicate high temperatures.

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.t NRC FORM 318 (6-77)

1. U. S. GOVE RNMENT PRINTING OF FICE 1977-237-025

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