ML20076K624
| ML20076K624 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 07/01/1983 |
| From: | De Lorenzo R WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Sternberg D NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, GO1-83-0352, GO1-83-352, NUDOCS 8307180034 | |
| Download: ML20076K624 (3) | |
Text
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e, Washington Public Power Supply Systpq P.O. Box 968 3000 GeorgeWashingtonWay Richland, Washington 99352J/{60,9 372-5000 fMJg. O NG/0;g!,/fy July 1, 1983 Responds to: G01-82-0438 G01-83-0352 Response required by: N/A Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Attention: Mr. D. M. Sternberg, Chief Reactor Projects Branch No. 1
Subject:
NUCLEAR PROJECTS N0. 1 & 4 DOCKET NOS. 50-460 & 50-513 10CFR50.55(e) POTENTIALLY REPORTABLE CONDITION, OK0 NITE CABLE
Reference:
1.
G01-82-0438, dated July 16, 1983, D.W. Mazur to R.H.
Faulkenberry Reference 1 provided an interim report on a potentially reportable deficiency under 10CFR50.55(e).
Tha subject deficiency deals with deformation of the conductor insulation in cable manufactured by Okonite, and Supply System proposed to provide updates on a yearly basis or more frequently, if new information became available.
Attachment A to this letter provides an update description of the deficiency and the action being taken by the Project.
Due to the current extended construction delay at the Project, it is not possible to provide a final completion date for the corrective action.
Therefore, the Supply System will provide an interim update report no later than Construction restart.
If you have any questions or desire further information, please advise.
I R. A. De Lorenzo, Program Director WNP-1/4 RAD: GAB:pp Attachment A cc: TA Mangelsdorf, BPC 861 V. Mani, UE&C 897 HW Kwan, UE&C, PA 806 V. Stello, NRC 4
I FDCC 899 ORM 847 8307180034 830701 PDR ADOCK 0b000460
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PDR 1.
i ATTACHMENT A DOCKET NOS. 50-460 AND 50-513 REPORTABLE CONDITION 10CFR 50.55(e)
OKONITE COMPANY CABLE INSULATION THICKNESS INTERIM REPORT NO. 2 BACKGROUND During the electrical contractor's (Foley-Wismer and Becker) cable termination activities in April 1982, difficulty was encountered in removing the outer jacket from the multi-conductor primaries (individual conductors) contained in seven (7) conductor #12 AWG (7/C-#12), two (2) conductor #12 AWG (2/C-#12), three (3) conductor #12 AWG (3/C-#12),
twelve (12) conductor #12 AWG (12/C-#12) and three (3) conductor #10 AWG (3/C-#10) cable.
Based on the cables involved, the Project's initial conclusion was that the problem was isolated to cable manufactured in 1980 and appeared to be caused by individual conductor insulation being fused to the cable jacket.
Inspection of the individual conductors disclosed that the insulation was deformed for certain cable types and that the thickness of the insulation appeared to not meet the contract specification requirements.
DESCRIPTION OF DEFICIENCY Okonite Company performed examinations / tests on samples of the suspect cable to determine the extent of the identified discrepancy.
As a result of these examinations / tests it was concluded that the insulation on the individual conductors of the 7/C-#12 and 3/C-#10, manufactured during 1980, were below the minimum wall thickness as required in the specification.
Okonite Company's evaluation of the condition concluded that this problem was the result of a series of the following items:
1.
Filler may have moved out of the normal location and, therefore, did r.ot absorb the pressure and tension equally, resulting in conductor distortion.
2.
Let-off reel tensions in cabling were not consistent allowing one conductor to be forced down and distorted by other corductors during cabling and jacketing.
3.
Close tolerance tools in jacketing set-up caused distortion due to normal variation insulated conductor diameters.
4.
Temperatures during curing were higher than normal magnifying the slight distortion that normally occurs.
5.
Abnormal let-off and take-up reel tension during jacketing operation causing conductors to become distorted during curing cycle.
Attachment A In order to determine if other multi-conductor cable contained the same deficiency as noted above, forty-four (44) additional samples were sent to the Okonite Company for examination / testing.
Samples were taken from the following type of 1980 cable which were located in the reel yard: 3/C-#10, 2/C-#12, 3/C-#12, 7/C-#12 and 12/C-#12.
Samples were also taken of the above noted types from field installed 1980 cables.
Since the Project had received Okonite cable which was manuf actured during the 1979 and 1981 time period, samples were taken of the above noted types for these two years also.
The Okonite Company stated in their letter to the Engineer (United Engineers and Constructors) that examination of the forty-four (44) additional cable samples were all found to be within the specification requirements, i.e.,
wall thickness were all in accordance with the specification. Okonite also concluded that we were dealing with two (2) isolated situations.
SAFETY IWLICATIONS The identified cable types are utilized in control and low power application.
Since the cable is designed for a voltage rating which exceeds the actual in service voltage that this cable would be subjected to and due to the fact that the Project has made a conscious decision to replace the cable, it is indeterminate as to the impact this cable would have on plant safety.
CORRECTIVE ACTION TAKEN TO DATE Seventeen (17) reels of 7/C-#12 and fourteen (14) reels of 3/C-#10 have been identified as possibly having the insulation thickness problem.
These reel s were identified as nonconforming on 1-CNCR-218-1065, 1-CNCR-218-1089 (previously incorrectly noted as 1-CNCR-218-1083) and 1-BNCR-105-03 (previously incorrectly noted as 4-CNCR-218-007).
WNP-1 and 4 cable which was not installed has been returned to Okonite with replacement to be provided by Okonite.
The circuits which have been installed to date using the suspect cable were identified by Foley-Wismer and Becker and the listing sent to the Engineer.
Circuits have only been installed in Unit 1.
The Engineer has determined that sixteen (16) 7/C-#12 cables have been i
installed in cable tray which will be removed and replaced with new cable.
Six (6) 7/C-#12 cables were installed in raceway (conduit and tray combination) which will be abandoned in place.
New cable will be i
installed to replace these cables. No 3/C-#10 had been installed at the l
time of construction deferral.
l l
Due to the current construction delay at WNP-1 and 4, it is not possible a
to provide a date when the cable will be replaced.
As a result, the Supply System will provide an interim up-date report no later than construction restart.