ML18022A474

Submits Addl Info Re Testing of Control Room Area Ventilation Sys in Emergency Recirculation Mode.Temp Maint Test Will Be Performed & Completed within Next Few Wks

ML18022A474
Person / Time
Site:	Harris
Issue date:	12/02/1986
From:	Zimmerman S CAROLINA POWER & LIGHT CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
NLS-86-444, NUDOCS 8612110079
Download: ML18022A474 (3)

Text

ATTACHMENT 1 Carolina Power 8 Light Company OEC 02 1986 SERIAL: NLS-86-ti4tt Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation United States Nuclear Regulatory Commission Washington, DC 20555 SHEARON HARRIS i'v'UCLEAR POWER PLANT DOCKET NO. 50-F00/LICENSE NO. NPF-53 CONTROL ROOM HABITABILITYIN EMERGENCY RECIRCULATIO~ MODE

Dear Mr. Denton:

Carolina Power R Light Company hereby submits additional information concerning testing of the Control Room Area Ventilation System (CRAVS) in the emergency recirculation mode. During CPRL's presentation to the ACRS on 3anuary 12, 1984, CPRL indicated that the Control Room Ventilation System would be tested in the recirculation mode to determine its ability to maintain I/O inch water~auge positive pressure as well as verify the svstems cooling capability. In the ACRS letter to the 4RC=

dated 3anuary 16, 198ii, 3. C. Ebersole to N.3. P'alladino, the ACRS expressed a desire to 'e kept informed of the results of these tests.

As part of an operations surveillance test, the system's ability to pressurize the Control Room area was tested in November 1986 with the system aligned in the emergency recirculation mode with makeup air. In this alignment, )he system exceeded the 1/8 inch watergauge pressure criteria relative to adjacent areas as identified in the FSAR and Technical Specifications i.e., effectively > I/O inch (differential pressure between the Control Room and outside atmospheric pressure) pressure at a make-up flowrate (pressurization rate) ( 315 cfm. Although system balancing has not yet been completed, balancing, as such, should not directly impact the system's ability to achieve design E.

As far as the system cooling capacity is concerned, the capacity of the CRAVS cooling coils was verified in conjunction with a preoperational test performed in 3uly of this year. During this test, the coolers exhibited greater than a 25 percent margin over the cooler vendor specifications. While this is not a direct measure of the resulting Control Room area temperature, it is a good indication that when performed, the temperature maintenance test will be satisfactory. Preparations are underway to perform this temperature maintenance test and it is expected that it will be completed within the next few weeks.

Even though final integrated system testing has not been completed, the tests performed to date provide enough assurance that this Control Room Area Ventilation System v'ill function as designed in all modes of operation. If you have any questions or would like to discuss this further, please contact Mr. Steven Chaplin at (919) 836-6623.

Yours very truly, S..

~ ~ Zi erman nager Nuclear Licensing Section SDC/bmc (5078SDC) cc: Mr. B. C. Buckley (NRC)

Mr. G. F. Maxwell (NRC-SHNPP)

Dr. 3. Nelson Grace (NRC-RII) 411 Fayettevrlle Street ~ P O. Box t55t ~ Rateign N. C 27602

ATTACHMENT 2 CgL-9522 hucteai Tect;tttttttgy Vfestlngho use Power Systems Systems D.ristott Electric Corporation Botl355 Pittsbetgtt P e~esytvan:a 1 5230 6355 November 25, 1985 Mr. L. I. Loflin, Managert Harris Project Engineeri'n)

Carol1na Power & Light Company P.O. Box 101 New H111,.NC,, 27562 AROLINA POWER & LIGHT COMPAN SH ARON HARRIS NUCLEAR POWER PLANT Post Modification Field Ex erienke on Counterflow Preheater Tube Dea r Mr. Lo f 1 in: I Attached .per your req uest is the information on h e op t rating experience of Westinghouse counterflow' od1f ied steam generators. W trust CP&L will find th1s 1nformation useful.'

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If/ there are any questions I ~

, please feel free to call u l

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Very truly you Sr WESTINGHOUSE E ECTRIC CORPORATION I ~

I <A. T. Parke.r, H p r+,g anager Carolina Power & L1ght Project I ~

CK/cm/2734F:1 Attachment cc: L.

'. '. Lof 1 in,,

A. Watson, CP&L Sit e Site 2L, 1L, 3L, 2A lA

'P&L

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.A..C. Anderson, Ebasco L..Rowell, CP&L Site 1L, 3A lA

'.'. J. L.'illis, Plant Ge neral Manager, CP&L Site 1L, 1L, 1A lA R. E. Lumsden, CP&L H. Martin, CP&L 1Lr 1A c

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G. L. Forehand, CP&L 1te 1L, 1A lL R..S. Pollock, W Ral,e gh t.'

I

POST HODIF ICATION FIELD E IENCE ON

, COUiI TERFLOH PREHFATFR TUBE VIBRA ION AND HEAR I

Post modificatioq tube inspection data have b en obtained from three plants with counterflow preheater steam gener tors (Models 04, 05 and E) and vibration data have been acquired n one plant.

~

In one'nit,~

the,two Hodel 04 steam generator have been inspected after 3 years of post-modification operating xperience, There were no reportable indications of tube wear in the pr'heater (20$ threshold

'sensitivity).

a Eddy current inspection of the three Model E ~team generators in each of two units afte'r one c cle of o eration res lted in no re P ortable wear. In addition, expanded tubes were inspe)ted with a UT method which has a'sensitivity of about one mil wall thickness and can detect the small waI1 thinning due to tube expansion No measurable wear was detected with this inspection method.

Tube vibration data were obtained on one expa ded tube and two unexpanded tubes, during operation of a Siodel f steam generator.

The results indicated small vibration levels )nd G. delta values less.

than .3 g-mils.~,This G delta value is almost 3 orders of magnitude lower than the maximum premodification values .Tube vibration data were'also required for an expanded tube'in a kodel D4 steam generator.

The G delta ~alIje for this tube was .4 g-milsI Hith extensive plate

. posit>on sear chingI to maximize tube response,,:a maximum G delta value 1

. of approximat ely,4 was measured in laboratory flow model testing of the po'st-mod> fication conditions. This value;is less than the design oh]ective va ue and is approximately a factor of 50 lower than the maximum premodification values.

i:. l Hodi f i ed Hodpl f)4, and 05 steam generators in wo other units are

~ <~ ~ cur'rently operating iri the first fuel cycle. These units are expected to complete first cycle in'spections in 1987.

I In sugary, fiel experience to date indicate no reportable wear on s

the 8 steam )enerators that have been inspect d and low vibration levels on counterflow preheater steam generat rs. These data support

,the adequacy'of, the counterflow preheater mod fications for the Hodel

04. units at hehron Harris-l.

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