ML20198D684
| ML20198D684 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 10/17/1985 |
| From: | Hufham J TENNESSEE VALLEY AUTHORITY |
| To: | Grace J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| NUDOCS 8511120413 | |
| Download: ML20198D684 (3) | |
Text
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i TENNESSEE VALLEY AUTHORITY CHATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II f
October 17, 1985 ca BLRD-50-438/85-03
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BLRD-50-439/85-03 U.S. Nuclear Regulatory Commission 3
Region II cc Attn:
Dr. J. Nelson Grace, Regional Administrator 101 Marietta Street, NW, Suite 2900 to Atlanta,' Georgia 30323 CO
Dear Dr. Grace:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - POTENTIAL DEFICIENCY IN IMPROPERLY RATED FIELD WIRING TO SOLENOID VALVES - BLRD-50-438/85-03, BLRD-50-439/85-03
- SECOND INTERIN REPORT The subject deficiency was initially reported to NRC-0IE Inspector A. Ignatonis on December 13, 1984 in accordance with 10 CFR 50.55(e) as NCR BLN REB 8418. This was followed by our first interim report dated January 10, 1985.. Enclosed is our second interita report. We expect to submit our next report no later than six months before the fuel loading of unit 1.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours.
TENNESSEE VALLEY AUTHORITY
. h.
. W. Hufham, Manager Licensing and Risk Protection Enclosure cc:
Mr. James Taylor, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Comunission Washington, D.C.-
20555 Records Center (Enclosure)-
Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 8511120413 85 POR ADOCM O 38 PDR S
l An Equal Opportunity Employer gg I
e, ENCLOSURE BELLE!*0NTE NUCLEAR PLANT UNITS 1 AND 2 POTENTIAL DEFICIENCY Ill IMPROPERLY RATED FIELD WIRING TO SCLENOID VALVES BLRD-50-438/85-03, BLRD-50-439/85-03 NCR BLN EEB 8418 10 CFR 50.55(e)
SECOND INTERIM REPORT l
Description of Deficiency A deficiency has been identified at Bellefonte Nuclear Plant (BLN) involving field-installed electrical cables. Specifically, field wiring that terminates within the housing of certain solenoid valves has insulation that is not rated for temperatures which could possibly be generated within the valves. This condition was originally identified in NRC-OIE Information Notice 84-68.
Two manufacturers of solenoid valves procured by TVA for BLN and requiring field wiring to terminate within the housing are Target Rock and Valcor.
These valves have been identified as having potential internal temperatures reaching 2800F. TVA presently uses wire with insulation rated at either 900 0
C (194 F) or 1250C (2570F) to terminate solenoid valves.
The apparent cause of this deficiency is that there was a lack of documentation on the operating valve housing temperatures.
Interim Progress All electrical schematics (wiring diagrams) containing IEEE Class 1E devices were reviewed for Class 1E solenoid valves whose wiring was terminated internally to the solenoid housing (as opposed to those with spliced pigtails where all internal wiring is furnished by the solenoid manufacturer). One hundred and twenty-one (121) valves for unit 1 and one hundred and nine (109) valves for unit 2 have been identified which will require corrective action.
Two different corrective actions are required.
One hundred and fifty-six (156) valves use Conax connectors for a pressure seal. At present, this connector is connected directly to the valve housing. The cabling is acceptable for the elevated temperature, but the material used as the pressure seal is not. The corrective action is to separate the connector from the valve by several feet of flexible hose so that the connectcr is not exposed to the elevated temperature.
This is being reflected on conduit and grounding (C&G) documentation. The corrective action for the remaining seventy-four (74) solenoid valves is to replace several feet of the 90 C or 1250C cable (from the solenoid 0
terminals to a splice box) with 200 C cable. This is being reflected on t
0 the electrical schematics and C&G documentation.
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Once the electrical schematics and C&G documentation are corrected, they will be issued to construction for rework of the deficiencies. A final report will be submitted on this item after completion of all corrective action, but no later than six months prior to fuel load of unit 1.
TVA is currently investigating this deficiency to determine actions to prevent recurrence for BLN. Nonconformance reports BFN EEB 8415, SQN EEB 8411 and WBN EEB 8425 have been prepared to address this problem at Browns Ferry, Sequoyah and Watts Bar Nuclear plants.
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