ML20062D083
| ML20062D083 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 07/16/1982 |
| From: | Mazur D WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Faulkenberry R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, GO1-82-0438, GO1-82-438, NUDOCS 8208050448 | |
| Download: ML20062D083 (4) | |
Text
_ _ _ _ _
Docket Nos. 50-460/513
- 50. 55 (c) Report fl
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Washington Public Power Supply System P.O. Box 968 3000 GeorgeWashingtonWay Richland, Washington 993523509) 372-5000 D
/!! S r.p July 16, 1982 G01-82-0438 in; Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, California 94596 Attention:
R. H. Faulkenberry Chief, Reactor Construction Projects Branch
Subject:
NUCLEAR PROJECTS 1 AND 4 DOCKET NOS. 50-460 AND 50-513 POTENTIALLY REPORTABLE CONDITION OK0 NITE CABLE
Reference:
1)
Telecon ME Rodin, Supply System to PP Narbut, Region V Nuclear Regulatory Commission, dated April 21, 1982.
2)
G01-82-0277, RW Root to RH Faulkenberry, dated June 2, 1982.
Reference 1) informed your office of a potentially reportable deficiency under 10CFR50.55(e). The subject deficiency deals with deformation of the conductor cable manufactured by Okonite.
Reference 2) informed you that a reportability determination would be made upon completion of examination and testing by Okonite.
Attachment A, to this letter, provides the Supply System interim report on the above caption condition. The attachment includes a statement of the problem and description of the safety implications associated with the Okonite cable.
To date, we have been unable to establish a completion schedule for the replacement of the cable or when the Architect Engineer, United Engineers and Constructors, will detemine the need for removing installed cable. Due to the construction slowdown at WNP-1, we will provide you with updates on a yearly basis or more frequently when new information becomes available.
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R. H. Faulkenberry July 16, 1982 Okonite Cable G01-82-0438 Page 2 If you have an questions or desire further information, please advise.
D. W. Mazur Acting Program Director DWM:JMS:1m Attachment cc: CR Bryant, BPA (399)
JP Laspa, Bechtel (860)
V. Mani, UE&C (897)
A. Toth, NRC V. Stello,- Director of Inspection, NRC FDCC (899)
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t ATTACHMENT A DOCKET NOS. 50-460 AND 50-513 REPORTABLE CONDITION 10CFR 50.55(e)
OKONITE COMPANY CABLE INSULATION THICKNESS INTERIM REPORT 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 disclcsed 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 insula-tion 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 not 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 conductors 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.
~, - - _ _. _
r 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 manufactured 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 specifica-tion. Okonite also concluded that we were dealing with two (2) isolated situations.
SAFETY IMPLICATIONS The identified cable types are utilized in control and low power applica-tion. 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 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 reels have been identified as nonconforming on 1-CNCP-?lR-1065, 1-CNCR-218-1083 and 4-CNCR-218-007. Cable which has not been installed will be returned to Okonite with replacement provided by Okonite.
The circuits which have been installed to date using the suspect cable will be identified by Foley-Wismer and Becker and the listing sent to the Engineer. Circuits have only been installed in Unit 1.
Most of the cable that has been installed is direct buried. The direct buried cable will be abandoned and replaced with new cable.
For those circuits which have been installed in cable tray, the Engineer will make a determination as to the need to remove the cable or abandon the cable in place. At this time it is not anticipated that cable will be removed from the cable tray unless the tray loading criteria may be jeopardized.
Due to the current construction delay at WNP-1, it is not possible to provide a date when the cable will be replaced or when the Engineer will complete the determination as to the need for removing cable from the tray.
Once these dates have been established, we will so notify you.